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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to inspection apparatuses for optical transmission device used in optical communication. More particularly, the present invention relates to an inspection apparatus suitable for easy inspection of a specific wavelength in optical transmission device used in a communication system employing a plurality of wavelengths.
[0003] 2. Description of the Related Art
[0004] In order to effectively utilize optical fiber, simultaneous and bidirectional transmission has been made between each subscriber and a central station with a single optical fiber. FIG. 6(A) is a schematic view showing an example of a known optical communication system. This system is generally used when a plurality of optical fibers each perform bidirectional transmission, and is an optical fiber network in which optical fiber cable 103 are led from an optical transmission apparatus 101 , such as an optical transmission module, in a central station 100 to subscribers 102 . The optical transmission apparatus 101 is an assembly of multiple optical transmission devices 104 , as shown in FIG. 6(B), and each subscriber 102 also has an optical transmission device (not shown). That is, each subscriber 102 and the central station 100 are connected by the optical fiber cable 103 through their respective optical transmission devices.
[0005] [0005]FIG. 7 shows an example of an optical transmission device that performs single-optical-fiber bidirectional transmission. In this optical transmission device 104 , a light-emitting device 111 or a light-receiving device 112 is optically coupled to each fiber of an optical multi-fiber cable 103 through a PC-type or SC-type connector 105 . More specifically, an optical fiber 110 connected to the connector 105 , a lens 113 , a wavelength selective filter 114 , a lens 115 , and the light-emitting device 111 , such as a laser diode (LD), are arranged coaxially. The light-receiving device 112 , such as a photodiode (PD), is placed perpendicular to the axis of the optical fiber 110 with a lens 116 therebetween. The wavelength selective filer 114 has a function of separating a transmission signal and a receiving signal.
[0006] The optical fiber cable 103 is led to the optical transmission device 104 and is divided into individual fibers, which are connected through the connectors 105 to the corresponding optical transmission devices 104 arranged in parallel in the horizontal direction, as shown in FIG. 6(B).
[0007] In general, an optical transmission device performs transmission and receiving using two types of light having different wavelengths, and the wavelengths used for the subscribers and the central station are different. More specifically, the optical transmission device on the subscriber side transmits light having a wavelength of 1.3 μm and receives light having a wavelength of 1.55 μm, and conversely, that of the central station transmits light having a wavelength of 1.55 μm and receives light having a wavelength of 1.3 μm, for example.
[0008] Such an optical transmission device can be used for both the subscriber and the central station by exchanging a wavelength selective filter and an LD chip. Therefore, component sharing, reduced production cost, and high economical efficiency can be achieved. Moreover, this system is extremely economical because simultaneous and bidirectional transmission can be accomplished with a single optical fiber.
[0009] In the above-related art, however, a simple visual assessment of whether the optical transmission device is provided for the subscriber or for the central station is impossible.
[0010] As described above, the optical transmission devices for the subscriber and the central station share most components except for a wavelength selective filter, an LD chip, and the like provided inside the casing. Moreover, since the single optical fiber is used, there is no difference in outer shape between the optical transmission devices. Accordingly, it is difficult to discriminate between the optical transmission devices by appearances. Conventionally, the optical transmission devices can be discriminated only by the type identifier printed on the surface of the casing.
[0011] Therefore, if an optical transmission device for a subscriber and an optical transmission device for a central station are inadvertently interchanged, that is, for example, if an optical transmission device for a subscriber is installed in the central station, it is difficult to check which optical transmission device is placed in the wrong position. In this case, it is time consuming to construct the system, work efficiency is reduced, and the cost is increased.
[0012] The above-described drawback has promoted a demand to achieve an inspection apparatus that can easily discriminate between an optical transmission device for a subscriber and an optical transmission device for a central station when laying a communication system that is capable of simultaneous and bidirectional transmission with a single optical fiber.
SUMMARY OF THE INVENTION
[0013] Accordingly, it is a primary object of the present invention to provide an inspection apparatus that can easily identify an optical transmission device as to whether the optical transmission device used in single-optical-fiber bidirectional transmission is provided for a subscriber or for a central station.
[0014] The above object is achieved by selecting a specific wavelength from optical signals transmitted from an optical transmission device and displaying the wavelength.
[0015] According to one aspect of the present invention, an inspection apparatus for an optical-transmission device comprises a coupling means to be optically coupled to the optical transmission device, a selecting means for optically separating and selecting an optical signal of a specific wavelength out of a plurality of optical signals having different wavelengths transmitted from the optical transmission device, a converting means for converting the selected optical signal into an electrical signal, and a displaying means for displaying the selected wavelength according to the electrical signal.
[0016] In this inspection apparatus of the present invention, a simple check of the wavelength of a transmission signal from the optical transmission device can be done visually by selecting only a signal with a specific wavelength from a plurality of signals having different wavelengths transmitted from the optical transmission device and by displaying the selected wavelength. That is, by separately assigning specific wavelengths of transmission signals from the optical transmission device to the subscriber and the central station, it is possible to easily check, on the basis of the wavelength detected by the inspection apparatus, whether the optical transmission device is provided for the subscriber or for the central station. Therefore, when a communication system that performs simultaneous and bidirectional transmission is laid, it is possible to easily check whether an optical transmission device is provided for the subscriber or for the central station, and thereby to reduce the possibility of placing an optical transmission device for the subscriber and an optical transmission device for the central station in the wrong position.
[0017] The present invention will be described in more detail below.
[0018] An optical transmission device to be inspected by the inspection apparatus of the present invention generally has a connector. Therefore, in the present invention, it is preferable that the coupling means be an optical fiber connector that can be simply coupled to an optical transmission device having a connector.
[0019] Preferably, the converting means is a light-receiving device (photodiode (PD)). In order to check a plurality of wavelengths, while a plurality of light-receiving devices, each having one light-receiving portion, may be provided, it is more preferable to provide a light-receiving device having a plurality of light-receiving portions. In the latter case, a plurality of wavelengths can be detected by a single light-receiving device, and the size of the inspection apparatus can be reduced further.
[0020] Preferably, the displaying means is a light-emitting device, such as a light-emitting diode (LED), that can convert a converted electrical signal into visible light. One displaying means may be provided to display corresponding to a specific wavelength, or two or more displaying means may be provided to display corresponding to a plurality of wavelengths. Furthermore, at least one of a driving IC for the light-emitting device and a signal amplifier for the light-receiving device may be provided.
[0021] While the selecting means may be a combination of a wavelength branching filter and a mirror, more preferably, it may be a multilayer filter, such as a wavelength division multiplexing (WDM) filter, in order to reduce the size of the inspection apparatus. Alternatively, the selecting means may be a Mach-Zehnder interferometer formed in a part of an optical waveguide. This is preferable because the inspection apparatus can be integrated. The Mach-Zehnder interferometer can separate wavelengths by the distance between optical waveguides and the length of a parallel portion of the optical waveguides. The distance between the optical waveguides and the length of the parallel portion may be appropriately determined in accordance with the wavelength to be checked. A platform on which the optical waveguides are formed may be an Si substrate. The Si substrate can be subjected to high-precision processing of the order of μm by photolithography and etching, and optical waveguides can be easily and precisely formed thereon. The optical waveguides include a SiO 2 /GeO 2 optical waveguide or a polymer optical waveguide. The SiO 2 /GeO 2 optical waveguide includes various types in which SiO 2 and GeO 2 serving as components are mixed at different ratios. The polymer optical waveguide is made of polyimide or fluorinated polyimide.
[0022] The size of the inspection apparatus can be further reduced by using the light-receiving device having a plurality of light-receiving portions, and multilayer filters. It can, for example, be reduced to a size substantially equal to the size of an optical transmission device (data link) to be inspected. Accordingly, the inspection apparatus of the present invention is easily portable and highly mobile, and can be used easily at a system construction site.
[0023] While the wavelengths to be checked may be appropriately determined, two wavelengths, one of 1.3 μm band and one of 1.6 μm band, are preferably used because they are most frequently used by an optical subscriber system. It is desirable to set the wavelengths to be checked in the range from 1.3 μm to 1.6 μm, so that the inspection apparatus is applicable to coarse wavelength division multiplexing (CWDM) and dense wavelength. division multiplexing (DWDM).
[0024] Preferably, the inspection apparatus is covered with a casing for mechanical protection.
[0025] As described above, the inspection apparatus of the present invention provides a great advantage of simple checking of the wavelength of a transmission signal from the optical transmission device. Accordingly, it is possible to easily check at a system construction site whether an optical transmission device is provided for a subscriber or for a central station, and thus prevent arrangement error. In particular, by using a PD having a plurality of light-receiving portions or a Mach-Zehnder interferometer, the size of the inspection apparatus can be further reduced, mobility can be enhanced, and cost can be reduced.
[0026] Further objects, features, and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] [0027]FIG. 1 is a schematic external view of an inspection apparatus according to the present invention;
[0028] [0028]FIG. 2 is an explanatory view of an optical system and an electrical circuit contained in a casing of the inspection apparatus;
[0029] [0029]FIG. 3 is a schematic view showing an optical system and an electrical circuit arranged on a ceramic substrate;
[0030] [0030]FIG. 4 is a schematic view of an optical system using a Mach-Zehnder interferometer;
[0031] [0031]FIG. 5 is a schematic view of an optical system in which a PD having two light-receiving portions in one chip is placed;
[0032] [0032]FIG. 6(A) is a schematic view showing an example of a known optical communication system, and FIG. 6(B) is a schematic view of an optical transmission device; and
[0033] [0033]FIG. 7 is a schematic view showing an example of an optical transmission device that performs single-optical-fiber bidirectional transmission.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] Embodiments of the present invention will be described below with reference to the attached drawings. The same components are denoted by the same reference numerals in the drawings, and redundant descriptions thereof are omitted. The scales in the drawings are not necessarily equal to those in the description.
[0035] [First Embodiment]
[0036] [0036]FIG. 1 is a schematic external view of an inspection apparatus for optical transmission device according to a first embodiment of the present invention. An inspection apparatus 1 has, in a casing 3 , an optical system serving as a selecting means for selecting the wavelength of a transmission signal from an optical transmission device (not shown), and an electrical circuit serving as a converting means for converting light having the selected wavelength into an electrical signal. At an end of the casing 3 , an optical connector 2 is provided as an optical coupling means for optical coupling to the optical transmission device. In this embodiment, the inspection apparatus 1 also includes a battery (not shown) provided as a power source in the casing 3 , an ON/OFF switch 4 provided on the surface of the casing 3 , and a display section 5 including LEDs 27 A and 27 B that emit light in response to an electrical signal.
[0037] [0037]FIG. 2 shows the optical system and the electrical circuit contained in the casing 3 of the inspection apparatus 1 . A dielectric multilayer filter 21 , such as a wavelength division multiplexing filter, a PD 22 made of InGaAs, a preamplifier (signal amplifier) 23 , a comparator 25 connected to a reference voltage 24 , a driving IC 26 , and an LED 27 A are arranged coaxially with an optical fiber 20 provided in the optical connector 2 . A PD 28 is disposed perpendicular to the axis of the optical fiber 20 , and a preamplifier 29 , the comparator 25 , a driving IC 30 , and an LED 27 B are provided in the enumerated order.
[0038] For example, in order to check whether light has a wavelength of 1.3 μm or a wavelength of 1.55 μm in such an optical system, only light with one of the wavelengths passes through a filter 21 and is received by the PD 22 , and light with the other wavelength is reflected by the filter 21 and is received by the PD 28 . Electrical signals from the PDs 22 and 28 are amplified by the preamplifiers 23 and 29 , respectively, and are directed to the comparator 25 such that the LED 27 A or 27 B which corresponds to the wavelength on the higher output level side is caused to emit light.
[0039] In this embodiment, the reference voltage is provided because, by changing the reference voltage, the wavelength of light can be checked to determine whether it is equal to the wavelength to be detected. The intensity of light having the wavelength to be detected can also be checked to determine its normality to meet a predetermined standard. That is, even when there is a noise level, it is possible to ascertain whether the output from each amplifier exceeds the noise level.
[0040] In the inspection apparatus 1 having this optical system and electrical circuit, when an optical transmission device to be inspected is connected to the connector 2 shown in FIG. 1 and the switch 4 is turned on, the LED 27 A or 28 A operates to emit light, depending on the wavelength of a signal transmitted from the optical transmission device. Therefore, on the basis of the operating LED, the inspecting operator can recognize the wavelength of the light transmitted from the optical transmission device.
[0041] [Second Embodiment]
[0042] A description will now be given of a second embodiment in which an optical system and an electrical circuit are arranged on a ceramic substrate. FIG. 3 is a schematic view showing the arrangement of the optical system and the electrical circuit on the ceramic substrate. As shown in FIG. 3, PDs 32 and 33 are provided, in a manner similar to that in the first embodiment, on a ceramic substrate 31 , which is made of Al 2 O 3 for example.
[0043] More specifically, a ferrule V-groove 35 in which a ferrule 34 is placed is formed at an end of the ceramic substrate 31 , and a V-groove 36 through which light from an optical fiber (not shown) provided in the ferrule 34 passes is formed in parallel with the axis of the optical fiber. A dielectric multilayer filter 37 is placed on the V-groove 36 . In the second embodiment, the dielectric multilayer filter 37 is placed at an angle of approximately 45° to the axis of the optical fiber. The PD 32 , a submount 38 , wiring patterns 39 on the substrate 31 , a preamplifier 40 , a comparator 41 , and a driving IC 42 are arranged in a direction parallel with the axis of the optical fiber. The driving IC 42 is connected to an LED provided on the upper side of the substrate 31 through pads 43 . A PD 33 and a submount 44 are disposed in a direction perpendicular to the axis of the optical fiber, and wiring patterns 39 , a preamplifier 45 , the comparator 41 , and a driving IC 46 are arranged in the enumerated order, and the driving IC 46 is similarly connected through pads 43 to an LED on the upper side of the substrate 31 . The devices are connected by bonding wires 47 . Preferably, such a substrate 31 , together with these devices provided thereon, is entirely resin-molded, and is then placed in a casing, as in the first embodiment, for mechanical protection.
[0044] In the second embodiment, since the optical system and the electrical circuit are arranged on the ceramic substrate, reliability can be increased and the size can be reduced. Therefore, low-cost mounting is possible.
[0045] [Third Embodiment]
[0046] A description will be given of a third embodiment of the present invention in which a Mach-Zehnder interferometer is used in an optical system. FIG. 4 is a schematic view of an optical system using a Mach-Zehnder interferometer. A first optical waveguide 51 and a second optical waveguide 52 are formed adjacent to each other on an Si platform 50 . The second optical waveguide 52 is a transmission line that is close to the first optical waveguide 51 at one end and is apart therefrom at the other end. Close portions of the first optical waveguide 51 and the second optical waveguide 52 constitute a Mach-Zehnder interferometer 53 (a portion encircled by a broken line in FIG. 4). PDs 54 and 55 are connected to the optical waveguides 51 and 52 , respectively. The first optical waveguide 51 serves as a transmission line for light with a wavelength of 1.3 μm, and the second optical waveguide 52 serves as a transmission line for light with a wavelength of 1.55 μm. A ferrule 57 having an optical fiber 56 is provided at an end of the Si platform 50 .
[0047] Such an Si platform 50 may be mounted on the ceramic substrate in the second embodiment to be combined with the electrical circuit. For easy mounting, it is preferable in this case to use waveguide-type edge-illuminated photodiodes as the photodiodes.
[0048] In the above configuration, a transmission signal transmitted through the optical fiber 56 is separated to the first optical waveguide 51 or the second optical waveguide 52 by the Mach-Zehnder interferometer 53 depending on its wavelength, and enters an LED (not shown) through the PD 54 or the PD 55 . Consequently, the LED which the signal enters emits light, allowing the wavelength of the transmission light from an optical transmission device to be detected. Such adoption of the waveguide structure can further reduce the size and cost of the optical system.
[0049] [Fourth Embodiment]
[0050] A description will now be given of a fourth embodiment in which a PD having two light-receiving portions in one chip is used. FIG. 5 is a schematic view of an optical system in which a PD having two light-receiving portions in one chip is placed. In the fourth embodiment, two dielectric multilayer filters 61 and 62 , which are different in terms of the wavelength of light that they reflect or allow to pass therethrough, and a PD array 64 having two light-receiving portions 63 A and 63 B are provided on a ceramic substrate 60 .
[0051] A ferrule V-groove 66 in which a ferrule 65 is placed is formed at an end of the ceramic substrate 60 , and a V-groove 67 is provided in parallel with the axis of an optical fiber in the ferrule 65 so that light from the optical fiber passes therethrough. The dielectric multilayer filters 61 and 62 bonded to a glass substrate 68 are placed at a distance from an end of the V-groove 67 and in front of the PD array 64 . A submount 70 is formed in the rear of the PD array 64 . For example, the dielectric multilayer filter 61 transmits light having a wavelength of 1.3 μm and reflects light having a wavelength of 1.55 μm. Conversely, the dielectric multilayer filter 62 transmits light having a wavelength of 1.55 μm and reflects light having a wavelength of 1.3 μm In FIG. 5, the upper light-receiving portion 63 A and the lower light-receiving portion 63 B convert light of 1.3 μm wavelength and light of 1.55 μm wavelength, respectively, into an electrical signal. Light from the optical fiber passes through either of the dielectric multilayer filters 61 and 62 , and enters either of the light-receiving portions 63 A and 63 B of the photodiode array 64 , depending on its wavelength. An electrical signal converted by the light-receiving portion 63 A or 63 B is introduced into an LED (not shown), thereby causing the LED to emit light. As a result, the wavelength of the transmission light from the optical transmission device can be detected by the LED that emits light.
[0052] That is, when light sent from the optical fiber has a wavelength of 1.3 μm, it passes through the dielectric multilayer filter 61 , and a current runs through the upper light-receiving portion 63 A. Conversely, when light from the optical fiber has a wavelength of 1.55 μm, it passes through the dielectric multilayer filter 62 , and a current runs through the lower light-receiving portion 63 B.
[0053] When a plurality of wavelengths are checked in this way, it is preferable that the number of display sections be equal to the number of wavelengths to be checked. In this embodiment, two display sections are provided. Furthermore, by placing the ferrule 65 and the filters 61 and 62 at a distance from each other, light having different wavelengths is spread so that it can pass through a plurality of filters. Therefore, it is preferable to appropriately determine the distance depending on the number of wavelengths to be checked.
[0054] By thus using the PD having a plurality of light-receiving portions, the light-receiving section can be further reduced in size. Moreover, a plurality of wavelengths can be checked with one PD chip, the cost of the inspection apparatus can be reduced further. By increasing the number of light-receiving portions of the PD to extend the range of wavelengths to be checked as in this embodiment, it is possible to easily check the wavelengths even in an optical transmission device for a multiwavelength system, such as a DWDM system, using 40 wavelengths, 80 wavelengths, or 120 wavelengths. Preferably, the wavelengths to be checked range from 1.3 μm to 1.6 μm because the range is frequently used by an optical subscriber system.
[0055] While the present invention has been described with reference to what are presently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. | An inspection apparatus for an optical transmission device comprises a coupling means to be optically coupled to an optical transmission device, a selecting means for optically separating and selecting an optical signal of a specific wavelength from a plurality of optical signals having different wavelengths transmitted from the optical transmission device, a converting means for converting the selected optical signal into an electrical signal, and a displaying means for displaying the selected wavelength according to the electrical signal. The wavelength of a transmission signal from the optical transmission device can be easily and visually checked by selecting a signal of a specific wavelength out of a plurality of signals having different wavelengths transmitted from the transmission device, and by displaying the selected wavelength by the displaying means. Thus, an optical transmission device used for single-optical-fiber bidirectional transmission can be easily checked as to whether it is provided for a subscriber or for a central station. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of U.S. Application Ser. No. 09/941,905, filed Aug. 29, 2001, now issued as U.S. Pat. No. 6,456,475 B1 on Sep. 24, 2002, which is a continuation of U.S. Application Ser. No. 09/192,871, filed Nov. 16, 1998 and issued as U.S. Pat. No. 6,337,788 B1 on Jan. 8, 2002.
BACKGROUND
The present invention relates to an off-line switched mode control system with fault condition protection.
Quantum leaps in electronic technology have led to the development of “smart” electrical and electronic products. Each of these products requires a steady and clean source of power from a power supply. One power supply technology called switched mode power supply technology operates at a high frequency to achieve small size and high efficiency. In such a switching power supply, an integrated circuit (IC) regulator is connected in series with the primary winding of a transformer to a rectified and filtered alternating current (AC) power line. The energy is transferred from the primary winding through an output secondary winding to the power supply output in a manner controlled by the IC regulator so as to provide a clean and constant output voltage. Additionally, a third winding called a feedback or bias winding may be used to provide a feedback signal and power to the IC regulator.
The voltage on the feedback winding tracks the output voltage present on the secondary winding. Thus, when a short occurs on the output of the secondary winding, the voltage on the feedback winding also goes low. Further, in the event of a short circuit condition, an overload condition on the output secondary winding or an open loop condition on the feedback winding, the regulator circuit responds to such conditions by delivering maximum power over a period of time. In such cases, the regulator circuit detects that the power supply is short circuited, overloaded at the output or has encountered an open loop condition. In any of these fault conditions, the regulator circuit goes into a mode called “auto-restart.” In the auto-restart mode, the regulator circuit tries to start the power supply periodically by delivering full power for a period of time (greater than needed for start up) and turns off the power supply for another period of time that is approximately four to ten times longer. As long as the fault condition is present, the regulator circuit remains in this auto-restart mode limiting the average output power to a safe, low value. When the fault is removed, auto-restart enables the power supply to start-up automatically.
SUMMARY
The invention protects a power supply from fault conditions. The power supply has an output and a feedback control loop, the feedback control loop having a feedback signal which cycles periodically when the power supply operates normally and which remains idle when the power supply is in a fault condition. In a first aspect, the circuit includes a switching device for controlling power delivered to the output and a timer coupled to the switching device and to the feedback signal. The timer disables the switching device to prevent power delivery to the output in a first predetermined period after the fault condition exists.
Implementations of the invention include one or more of the following. The timer may enable the switching device to deliver power to the output after a second predetermined period. The switching device may be alternately enabled for the first predetermined period and disabled for the second predetermined period when the fault condition exists. The switching device may be enabled upon removal of the fault condition. The switching device may be a power transistor. The timer may be a digital counter. An oscillator with a predetermined frequency may be coupled to the counter. The oscillator may have a control input for changing the predetermined frequency and a first current source coupled to the oscillator control input to generate a first frequency. A second current source may be coupled to the oscillator control input to generate a second frequency. The counter' output may be coupled to the fist and second current sources. The timer may be a capacitor which is adapted to be charged at a first rate from a first threshold to a second threshold to generate a first predetermined period. The capacitor may be discharged from the second threshold to the first threshold at a second rate to generate the second predetermined period. The capacitor may also be reset to a voltage below the first threshold each time the feedback signal cycles. The fault condition includes one or more of an output overload fault condition, an output short circuit fault condition and an open feedback control loop fault condition.
In a second aspect, a method for protecting a power supply having an output and a feedback control loop from fault conditions includes receiving a feedback signal from the feedback control loop, the feedback signal being adapted to cycle periodically when the power supply operates normally and to remain idle when the power supply is in a fault condition; timing the feedback signal to detect whether a fault condition exists in the power supply; and disabling the output after a first predetermined period after the fault condition is detected.
Implementations of the invention include one or more of the following. A switching device may be enabled to deliver power to the output after a second predetermined period. The switching device may be alternatingly enabled for the first predetermined period and disabled for the second predetermined period. The switching device may be enabled upon removal of the fault condition. The enabling step may enable a power transistor. The timing step includes digitally countering periods of time. A signal may be generated with a predetermined frequency. The generating step includes oscillating at a first frequency and a second frequency. The second frequency may be used when the fault condition exists. The timing step includes charging a capacitor at a first rate from a first threshold to a second threshold to generate a first predetermined period; and discharging the capacitor from the second threshold to the first threshold at a second rate to generate a second predetermined period. The capacitor may be reset to a voltage below the first threshold each time the feedback signal cycles.
In a third aspect, a circuit for protecting a power supply having an output and a feedback control loop from fault conditions includes means for receiving a feedback signal from the feedback control loop, the feedback signal being adapted to cycle periodically when the power supply operates normally and to remain idle when the power supply is in a fault condition; timing means coupled to the feedback signal to detect whether a fault condition exists in the power supply system; and means for disabling the output after a first predetermined period after the fault condition is detected.
Implementations of the invention include one or more of the following. The circuit includes a means for enabling a switching device to deliver power to the output after a second predetermined period. A means for alternatingly enabling the switching device for the first predetermined period and disabling the switching device for the second predetermined period when the fault condition exists may be used. The circuit may have a means for enabling the switching device upon removal of the fault condition. The switching device may be a power transistor. The timing means includes a digital counter. The circuit includes means for generating a predetermined frequency. The generating means includes means for oscillating at a first frequency and a second frequency. The circuit may include a means for applying the second frequency when the fault condition exists. The timing means includes a means for charging a capacitor at a first rate from a first threshold to a second threshold to generate a first predetermined period; and a means for discharging the capacitor from the second threshold to the first threshold at a second rate to generate a second predetermined period. A means for resetting the capacitor to a voltage below the first threshold each time the feedback signal cycles may be used.
In another aspect, a fault protected power supply includes a regulator coupled to a transformer having a primary winding. The transformer has a secondary winding coupled to a secondary output. The regulator receives a feedback signal from the secondary output which cycles periodically when the power supply operates normally and which remains idle when the power supply is in a fault condition. The power supply includes a switching device coupled to the primary winding of the transformer for controlling power delivered to the secondary output; an oscillator for generating a signal with a predetermined frequency; and a timer coupled to the oscillator and to the feedback signal, the timer disabling the switching device after a predetermined period of existence of a fault condition.
Implementations of the invention include one or more of the following. The power supply includes a means for changing the frequency of the oscillator. The timer alternatively enables and disables the switching means when the fault condition is present.
In another aspect, a method protects a power supply having a regulator coupled to a transformer having primary winding, the transformer having a secondary winding coupled to a secondary output, the regulator receiving a feedback signal from the secondary output which cycles periodically when the power supply operates normally and which remains idle when the power supply is in a fault condition. The method includes controlling power delivered to the secondary output using a switching device; generating an oscillating signal with a predetermined frequency; and timing the feedback signal with the oscillating signal and disabling the switching device after a predetermined period of existence of a fault condition.
Implementations of the invention include one or more of the following. The method includes changing the frequency of the oscillating signal. The method also includes alternatingly enabling and disabling the switching device when the fault condition is present.
In another aspect, a fault protected power supply has a regulator coupled to a transformer having a primary winding, the transformer having a secondary winding coupled to the secondary output. The regulator receives a feedback signal from the secondary output which cycles periodically when the power supply operates normally and which remains idle when the power supply is in a fault condition. The power supply includes a switching device coupled to the primary winding of the transformer for controlling the power delivered to the secondary output; a capacitor; means for charging the capacitor at a first rate from a first threshold to a second threshold to generate a first predetermined period and discharging the capacitor from the second threshold to first threshold at a second rate to generate a second predetermined period; and means coupled to the switching device, the capacitor and the feedback signal for alternately enabling the switching device during first predetermined period and disabling the switching device during the second predetermined period in the presence of a fault condition.
In yet another aspect, a method protects a power supply having a regulator coupled to a transformer having a primary winding. The transformer has a secondary winding coupled to a secondary output. The regulator receives a feedback signal from the secondary output which cycles periodically when the power supply operates normally and which remains idle when the power supply is in a fault condition. The method includes controlling power delivered to the secondary output using a switching device; charging a capacitor at a first rate from a first threshold to a second threshold to generate a first predetermined period; discharging the capacitor from the second threshold to first threshold at a second rate to generate a second predetermined period; and alternatingly enabling the switching device during the first predetermined period and disabling the switching device during the second predetermined period in the presence of a fault condition.
Advantages of the invention include one or more of the following. The invention protects the switched mode controller and associated components such as the diode and the transformer from various fault conditions. The feedback winding is not necessary. The protection is provided using a minimum number of components. Further, the power supply properly shuts down when it encounters a fault condition and automatically returns to an operating condition when the fault condition is removed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a fault condition protection device of the invention.
FIG. 2 is a plot illustrating the operation of the device of FIG. 1 .
FIG. 3 is a schematic illustration of a second embodiment of the fault condition protection device.
FIG. 4 is a plot illustrating the operation of the device of FIG. 2 .
FIG. 5 is a schematic illustration of a switched mode power supply in accordance with the present invention.
DESCRIPTION
Referring now to FIG. 1, a fault-protection circuit 200 is shown. The circuit 200 has a primary oscillator 111 which is connected to a counter 202 . The counter 202 can be reset by a feedback signal which clears registers Q 8 -Q 13 of counter 202 . The feedback signal is explained in more detail below.
An inverter 204 receives the 13-th bit output of counter 202 . The output of inverter 204 is provided to an AND-gate 206 whose other input is connected to a switching signal. The switching signal is derived from the oscillator 111 output and the feedback signal. This switching signal cycles periodically when the power supply operates normally. The switching signal is idled when the power supply encounters a fault condition. The output of AND-gate 206 in turn is provided to the gate of a switching transistor 208 . Counter 202 eventually causes an AND-gate 206 to shut-off switching transistor 208 and to perform auto-restart.
Turning now to oscillator 111 , a current source 122 generates a current I from a supply voltage 120 . The output of current source 122 is connected to the source of a p-channel MOSFET transistor 125 , whose drain is connected to a node 123 . Also connected to the node 123 through a p-channel MOSFET 182 is a second current source 184 . Current source 184 can supply current which is ¼ of the current I. The drain of transistor 182 is also connected to node 123 . The gate of transistor 182 is driven by an inverter 180 , whose input is connected to the gate of transistor 125 and to the counter output Q 13 .
The node 123 is connected to the sources of p-channel MOSFET transistors 126 and 132 . The drain of MOSFET transistor 126 is connected to the drain of an n-channel MOSFET transistor 128 . The source of transistor 128 is grounded, while the gate of transistor 128 is connected to its drain. The gate of transistor 128 is also connected to the gate of an n-channel MOSFET transistor 130 . The source of transistor 130 is grounded, while the drain of transistor 130 is connected to the drain of transistor 132 at a node 131 . Transistors 126 , 128 , 130 and 132 form a differential switch. The input of inverter 124 and the gate of transistor 132 are driven by a hysteresis comparator 136 . Output of inverter 124 drives the gate of MOSFET transistor 126 . Comparator 136 has an input which is connected to node 131 and to a capacitor 134 . The other node of the capacitor is connected to ground. In combination, transistors 126 , 128 , 130 and 132 , capacitor 134 , inverter 124 and hysteresis comparator 136 and current source 122 form an oscillator. The output of hysteresis comparator 136 is provided as an oscillator output and is also used to drive the clock input of counter 202 .
During operation, the feedback signal periodically pulses between a low state and a high state depending on the amount of power required on a secondary winding 922 (FIG. 5 ). Every time the feedback signal is low, the feedback signal resets a counter whose states are reflected by outputs Q 8 -Q 13 of counter 202 . The resetting of the counter associated with outputs Q 8 -Q 13 thus occurs regularly when no fault is present in the power supply. The cycling of the feedback signal constantly clears the output bit Q 13 such that the power transistor 208 is controlled by the switching signal when no fault is present. However, in the event of a fault condition, the feedback signal remains high for a sufficiently long time such that the counter associated with output bits Q 8 -Q 13 has enough time to increment output bit Q 13 . The setting of the output bit Q 13 causes inverter 204 output to go low and thus causes the output of AND-gate 206 to be deasserted. The deassertion of AND-gate 206 in turn disables switching transistor 208 . Also, when the counter output Q 13 goes high transistor 125 turns off to isolate primary current source 122 from node 123 . This turns on the transistor 182 via inverter 180 , thus allowing the ¼ I current to flow from the secondary current source 184 to node 123 . The state change of the counter output Q 13 causes the oscillator to switch at one-fourth of its normal frequency to achieve about 20% on time and 80% off time. This operation reduces the power delivered by the power supply under a fault condition as well as avoids the possibility of damage to the regulator device and other power supply components such as the output diode or the transformer (not shown).
FIG. 2 shows a timing diagram for the device of FIG. 1 . The timing diagram of FIG. 2 shows three periods: 211 , 213 and 215 . Period 211 is normal operation with the feedback signal going “low” more often than a predetermined count such as approximately 4096 clock cycles, thereby resetting the Auto Restart Counter before it counts up to 4096.
In Period 213 , the feedback signal has been “high” for 4096 continuous clock cycles due to a fault condition such as an output overload or short, so the circuit of FIG. 1 goes into the auto-restart mode. The oscillator frequency is divided by four and switching transistor 208 has been inhibited from switching, remaining in its off state. After 4096 clock cycles, switching transistor 208 is activated and the oscillator frequency switches back to normal frequency. This sequence will repeat itself as long as the feedback signal stays “high.”
In Period 215 , the overload condition or the short condition on the output of the power supply is removed and the feedback signal goes low, indicating the power supply output is in regulation. The circuit is now in normal operation with the feedback signal going “low” at least once every 4096 clock cycles. It is to be noted that the auto-restart capability as been described may not be used in all applications. Particularly, certain applications may disable the power regulator after detecting a fault condition and the disabling of the power regulator may continue until a user resets the power regulator, or until AC power is cycled OFF and then ON to the power regulator.
FIG. 3 shows an analog auto restart circuit. A current source 525 produces a fixed magnitude current 530 . Fixed magnitude current 530 is fed into first transistor 535 and mirrored to transistors 540 and 545 . Third transistor 545 is connected to a capacitor 550 via transistor 595 . Transistor 600 is also connected to the capacitor 550 . Transistor 600 is controlled by the feedback signal provided to inverter 605 whose output drives the gate of the transistor 600 . Node 400 is generated by the charging and discharging of capacitor 550 . Capacitor 550 has a relatively low capacitance which allows for integration on a monolithic chip in one embodiment of the IC regulator of the invention. Node 400 is provided to a hysteresis comparator 560 which compares its input with a lower limit of about 1.5 volts and an upper limit of about 4.5 volts. The output of comparator 560 is provided to the gates of transistors 585 and 595 . AND-gate 570 receives at one input the output of comparator 560 . AND-gate 570 enables switching transistor 572 to turn on and off. AND-gate 570 receives at a second input a switching signal which modulates the regulator output.
In operation, after the feedback signal goes high, capacitor 550 begins to charge from a level below 1.5 volts to an upper threshold of about 4.5 volts. Upon reaching 4.5 volts, the output of comparator 560 switches and discharges the capacitor 550 through transistors 545 and 595 . Node 400 then switches between the upper threshold of about 4.5 volts and the lower threshold of about 1.5 volts.
Signal 401 output of comparator 560 will be high until node 400 exceeds the upper threshold limit. When signal 400 is high, p-channel transistors 585 and 595 are turned off. By turning off transistors 585 and 595 , current can flow into and steadily charge capacitor 550 and increase the magnitude of node 400 . The current that flows into capacitor 550 is derived from current source 525 because the current through transistor 590 is mirrored from transistor 580 , which current is derived from transistor 540 .
Referring to FIGS. 3 and 4, in period 600 feedback signal 402 is switching and the system is in normal operation with switching transistor 572 controlled by the switching signal. At the end of period 600 a fault condition has been detected and the feedback signal stays high for an extended period of time (period 601 ). In period 601 , transistor 600 turns off, allowing capacitor 550 to be charged by current source 590 . When the voltage on node 400 has reached the second threshold, the output 401 of comparator 560 goes low, disabling the switching transistor 572 . Capacitor 550 will be discharged to the first threshold by current source 545 with switching transistor 572 disabled. This mode of oscillation continues until the feedback signal goes low again, indicating that the fault condition no longer exists. When the feedback signal 402 at the end of period 601 goes low, transistor 600 turns on and discharges capacitor 550 to a voltage below the first threshold. Comparator 560 output will go high and enable the switching signal to control the switching transistor 572 . In period 602 , the system has returned to normal operation with the feedback signal 402 going low at least once during a defined time period indicating that the regulator circuit is in regulation.
Referring now to FIG. 5, a switched mode power supply is shown. Direct current (DC) input voltage is provided to a Zener diode 912 which is connected to a diode 914 . The diodes 912 - 914 together are connected in series across a primary winding of a transformer 920 . A secondary winding 922 is magnetically coupled to the primary winding of transformer 920 . One terminal of the secondary winding 922 is connected to a diode 930 , whose output is provided to a capacitor 932 . The junction between diode 930 and capacitor 932 is the positive terminal of the regulated output. The other terminal of capacitor 932 is connected to a second terminal of the secondary winding and is the negative terminal of the regulated output. A Zener diode 934 is connected to the positive terminal of the regulated output. The other end of Zener diode 934 is connected to a first end of a light emitting diode in an opto-isolator 944 . A second end of the light-emitting diode is connected to the negative terminal of the regulated output. A resistor 936 is connected between the negative terminal of the regulated output and the first end of the light-emitting diode of opto-isolator 944 . The collector of the opto-isolator 944 is connected to current source 172 . The output of current source 172 is provided to the switching regulator logic 800 .
Connected to the second primary winding terminal is the power transistor 208 . Power transistor 208 is driven by AND gate 206 which is connected to inverter 204 and switching regulator logic 800 . Switching regulator logic 800 receives a clock signal 101 from an oscillator 111 . A counter 202 also receives the clock signal 101 from the primary oscillator 111 . The output of counter 202 , Q 13 , is used to switch in the current source 184 to supply current in lieu of the current source 122 when Q 13 is high.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, materials, components, circuit elements, wiring connections and contacts, as well as in the details of the illustrated circuitry and construction and method of operation may be made without departing from the spirit of the invention. | A circuit protects a power conversion system with a feedback control loop from a fault condition. The circuit has an oscillator having an input for generating a signal with a frequency and a timer connected to the oscillator input and to the feedback control loop. The timer disables the oscillator after a period following the opening of the feedback control loop to protect the power conversion system. | 1 |
This invention relates generally to measuring a stress condition in a borehole and more particularly to measurements including fracturing of a subterranean formation traversed by the borehole. The invention further relates to a downhole tool for fracturing of the subterranean formation.
BACKGROUND OF THE INVENTION
Formations in the earth are characterized by stress conditions which vary with depth and whose principal directions are generally vertical and horizontal. In the horizontal plane at any point, the horizontal stress reaches a maximum in one direction and a minimum at right angles to the maximum condition. Information concerning these maximum and minimum horizontal stress conditions is of substantial value in a variety of disciplines such as underground transportation systems, foundations of major structures, cavities for storage of liquids, gases or solids, and in prediction of earthquakes. Further, this information is essential in petroleum exploration and production, e.g. while drilling a well or borehole the information is useful for blowout prevention, in a completed well it is useful for evaluating hydraulic fracture treatment, and also in determining many critically important aspects of reservoir behavior, such as bulk and pore volume compressibility, permeability, direction of fluid flow, and reservoir compaction/surface subsidence.
Currently, the technique of hydrofracturing is often used to measure the least principal stress in the plane normal to the borehole axis, i.e., the normal plane. In hydrofracturing, the least principal stress in a normal plane is measured with a borehole injection test. While these injection tests are an accurate means of determining in-situ stresses and can be carried out at great depths, they are expensive, time consuming in that they require interruption of drilling to set borehole packers, and further, these tests are difficult to interpret.
In injection tests small volumes of fluid are pumped into small sections of the borehole, which are isolated by inflatable packers, with just enough pressure to create a small fracture. After each fracture of the formation, the pressure decline is measured as fluid leaks off. As long as the fracture is open, this pressure falloff should represent linear flow, and a plot of pressure falloff vs. the square root of time should be a straight line. Once the fracture closes, the pressure falloff is no longer linear and the slope of the pressure falloff vs. time plot will change. The point where this slope change occurs is interpreted to be the in-situ closure stress, which equals the minimum horizontal stress, for that depth.
The use of inflatable packers to isolate a test interval in a borehole is not only time consuming but can present another problem as these packers may cause unwanted fracturing of the formation. This unwanted fracturing would mean that the results of the fracturing tests are incorrect.
Accordingly, it is an object of this invention to improve fracturing of a selected location in a subterranean formation traversed by a borehole.
It is a more specific object of this invention to accomplish formation fracturing through a borehole which is filled with a fluid.
It is another more specific object to operate a downhole tool for formation fracturing without interrupting drilling operations.
It is yet another object to allow accurate calculation of principal horizontal stresses existing in the formation surrounding a vertical borehole.
It is yet another object to allow accurate calculation of principal stresses existing in the plane of the formation normal to an inclined borehole.
SUMMARY OF THE INVENTION
According to this invention, the foregoing and other objects and advantages are attained by determining in-situ the maximum and minimum principal stresses in a plane normal to a borehole penetrating a subterranean formation. The stress determinations are based on three actual measurements of breakdown pressure applied sequentially to the borehole wall along three radii which are offset from each other about the axis of the borehole at an angle of about 60 degrees. Sufficient pressure is selectively applied to the wall by a downhole jack to initiate three independent fractures in the formation with the fractures spaced apart according to the three offset radii. Standard equations for two-dimensional axial transformation are then applied using the three breakdown pressure measurements to obtain the magnitude and direction of the maximum and minimum principal stresses operating in a plane normal to the borehole axis.
In another aspect of this invention there is provided a downhole jack comprising a set of three individually expandable platens which are formed as 180 degree sections of a cylinder, with three of the cylinder sections arranged in a vertical stack to form the downhole tool. The included angle between the midpoint radius of adjacent platens is aligned on the downhole tool to be about 60 degrees.
In a preferred embodiment, pressure measurements are made while carrying on drilling operations by disposing a drill collar including the downhole jack and instrumentation for pressure measurement approximate to the drill bit. The drilling fluid pressure (i.e., mud pressure) is increased until it is slightly lower than the fluid pressure required to hydrofracture the borehole. In this pressure condition, an incremental increase in pressure is required to provide a breakdown pressure which will fracture the borehole, and this incremental pressure is supplied by the downhole jack. After the fracture has been created and the breakdown pressure recorded, the fracture is allowed to close. The bottom hole pressure is monitored to determine the pressure at which the induced fracture closes in a manner similar to the closure stress determined in the injection tests described above.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and intended advantages of the present invention will be more readily apparent by reference to the following detailed description in connection with the accompanying drawings, in which:
FIG. 1 is a schematic illustration of a wellbore including pressure measuring instruments and the downhole jack for fracturing the formation.
FIG. 2 is a cross-sectional illustration of a typical deviated borehole showing subterranean stresses.
FIG. 3 is a schematic illustration of one end of the borehole jack according to this invention.
FIG. 4 is a schematic illustration of the side of the borehole jack shown in FIG. 3.
FIG. 5 is a graphic representation of downhole pressure showing fracturing of the formation according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
This invention is directed to method and apparatus for determining the stress at a desired location in a borehole, and is applicable to vertically drilled boreholes and boreholes inclined at an angle up to about 25° from the vertical. In accordance with this invention the sum of the pressure exerted by a platen plus the pressure of the drill fluid provide a breakdown pressure which is required to fail the borehole wall. The breakdown pressure is directly related to the tangential stresses operating on the borehole wall at the fracture location. The tangential stresses measured at the three fracture locations are used to determine the maximum and minimum principal stresses operating in the normal plane, through the standard equations for two-dimensional axial transformation.
FIG. 1 illustrates schematically an apparatus located in a wellbore useful in performing the method of the present invention. A drill string 10 is suspended within borehole 30 in a formation 50. The drill string 10 includes a drill bit 20 attached to the end thereof for penetrating the earth 50 to produce the borehole 30. Disposed within the drill string 10 and preferably approximate the drill bit 20 are a plurality of drill collars 22 including a downhole jack and instrumentation for measuring pressure of the drill fluid, and the pressure exerted on the borehole walls by the platens of the downhole jack. Those skilled in the art are familiar with many drill collars and devices for use in making measurement while drilling (MWD) determinations which are conveniently incorporated within the drill string 10 as one or more drill collars 22. The data obtained by the measuring instruments included within drill collars 22 is conveniently stored for later manipulation within a computer 26 located on the surface. Those skilled in the art will appreciate that the data is transmitted to the surface by any conventional telemetry system for storage and manipulation in the computer 26.
FIG. 2 illustrates a section of a typically deviated borehole 40 passing through a plurality of rock formations. The stresses operating in the borehole illustrated at 40 of FIG. 2 include the vertical overburden stress designated as σ ob at 48 and the minimum horizontal stress for typical rock formations 52, 54, 56, and 58 designated as σ min . The maximum horizontal stress, which as previously stated operates at right angles to the minimum condition, is not illustrated. Those skilled in art familiar with formation stress conditions will recognize the magnitude of the minimum stress for the different formations relative to the overburden 48 such as a low minimum stress for sandy material at 52 and 58 e.g. σ min =(0.2-0.5)σ ob , and intermediate and high minimum stresses for other rock compositions such as shale and limestone illustrated at 54 and 56 where σ min =(0.5-0.7)σ ob for intermediate material, and σ min ˜σ ob for a high minimum stress.
Referring now to FIG. 3 there is illustrated the downhole jack 62 of the present invention which generally comprises three expandable platens 64, 66 and 68 with corresponding pistons 70, 72 and 74. As illustrated, platen 64 is in an extended position. The pistons are controllably extendable for moving the platens to contact and bear against a borehole wall. The pistons may be operated by hydraulic pressure or electric power which is provided through the drill string 10 as is well known to those skilled in the art.
FIG. 3 shows the radial arrangement of the piston 70, 72 and 74 such that each piston is angularly offset from the others about the axis of the jack 62 by an angle of 60 degrees. Thus, the initiation of each wellbore fracture is carried out sequentially in a different direction corresponding to the different radial spacings of the pistons. A previous fracture is allowed to close before initiating a subsequent fracture so that each measured breakdown pressure is independent of the others.
FIG. 4 better illustrates the stacking relationship of the platens such that each platen is vertically offset from the others by a convenient amount. The length of the jack 62 is not critical as long as the length does not exceed the thickness of the formation being fractured. Generally a length for the jack 62 of about two to about five feet is satisfactory.
Hydraulic fracturing of subterranean formations is well known. The present invention relates to determining the in-situ stress conditions at a desired depth in a borehole and includes inducing three independent fractures of the subterranean formation. The method of the present invention is best illustrated with reference to FIG. 5, which shows three breakdown pressures at 80, 82 and 84 required to fracture a formation in different radial directions at a desired depth in a borehole. More specifically the method includes positioning the downhole jack, which is part of the drill string, at a selected borehole depth such that the jack is disposed at the depth of the formation to be measured and the orientation of the platens is noted. Measurement of the pressure exerted on the borehole wall by the drilling fluid is recorded as illustrated by the solid portion 86 of the plot shown in FIG. 5. Next the first platen is extended to contact and bear against the borehole wall with pressure exerted on the wall gradually increased until a fracture is initiated. Pressure on the wall exerted by the first platen is illustrated by the dash line 88 in FIG. 5. Once the first fracture is initiated, as indicated at 80 in FIG. 5 by a sudden reduction in pressure, the platen is retracted and the borehole pressure is allowed to leak off as illustrated by the portion of the curve 90. The change in slope of the curve illustrated at 92 indicates closure of the fracture created by the first platen. The above procedure is repeated for the second and third platens to obtain breakdown pressures as shown at 82 and 84.
In accordance with this invention the downhole tool is used to obtain quantitative values for σ max and σ min which are defined as the maximum and minimum normal plane stresses that operate in a plane perpendicular to a borehole axis.
In vertical and near vertical boreholes the maximum and minimum normal plane stresses are the maximum and minimum horizontal principal stresses operating in rock formation surrounding the borehole. The downhole tool measures three radial stresses required to initiate three independent fractures oriented 60 degrees apart relative to the axis of the borehole. The three stresses, hereinafter referred to as S i , S j , and S k , are used to calculate R max and R min which are the maximum and minimum values for radial stresses necessary to fracture the borehole wall. Versions of the "Kirsch" equation for stresses surrounding a cylindrical hole in stressed solids are used to calculate σ max and σ min , the maximum and minimum normal plane stresses that operate in a plane that is normal to the borehole axis. For more details concerning the "Kirsch" equation see the text: Roegiers, Jean-Claude (1989), "Elements of Rock Mechanics", p. 2-1 through p. 2-22 found in Economides, M. J. and Nolte, K. G., Editors, "Reservoir Stimulation", Second Edition, Prentice Hall, which is incorporated herein by reference.
In accordance with the present invention the maximum and minimum principle horizontal stresses operating in a subterranean formation are determined by first ascertaining the maximum and minimum values for radial stresses required to initiate a fracture in the subterranean formation using the equations: ##EQU1## where: S=stress applied by the downhole jack, psi
i, j, k=indexes for direction of stress relative to some specified direction or azimuth, and
S i >S j >S k .
The maximum value for radial stress caused by the downhole jack R' max is given by R' max =A+B, and likewise
R' min =A-B where the "R" refers to radial stress and A and B are defined above.
The computed maximum and minimum radial stresses, R max and R min respectively, are obtained by adding the borehole pressure (bp) to the maximum and minimum radial stress as follows:
R max =R' max +bp
R min =R' min +bp
where
bp=borehole pressure i.e., drilling fluid (mud) pressure.
The orientation of R max is given by the angle theta (θ) in degrees which is drawn anticlockwise from the i direction. ##EQU2##
Finally the maximum and minimum principal stresses σ max and σ min operating the normal plane are computed using the maximum and minimum radial stresses in the following "Kirsch" equations that relate radial and tangential stresses surrounding a borehole to the principal stresses operating in the normal plane.
σ max =3R max /8+R min /8+P p /2
σ min = R min +σ max +P p !/3
where:
P p =formation pore pressure.
The downhole jack of this invention is designed to be applicable to a wide variety of subterranean materials ranging from sandy compositions to hard rock. Accordingly it should be noted that the jack may be used repeatedly at different depths within a borehole to determine stress conditions surrounding the borehole at different depths.
In this disclosure there is shown and described only the preferred embodiment of this invention which is applicable to oil production or exploration. It is to be understood that the invention is applicable to various other combinations and environments, accordingly various changes or modifications possible by those skilled in the art are within the scope of the inventive concept as expressed herein. | A borehole technique for in-situ determination of principal stresses operating in a plane normal to the borehole includes using a downhole jack to independently initiate three spaced apart fractures in a subterranean formation, measuring the breakdown pressure required to initiate the fractures and then using the measured breakdown pressures in two-dimensional axial transformation equations to compute the maximum and minimum stresses that are active in the normal plane. The technique is useful while drilling the borehole by lowering a jack having three platens that can be independently activated to bear against the borehole wall along three radii which are offset from each other about the borehole axis. In use each platen is extended in turn to bear against the borehole wall until a fracture is initiated. | 4 |
The invention concerns a glide tube ring for tube-in-tube systems, pipe conduits or the like. The glide tube ring according to the invention is provided on its back with axially spaced glides running parallel to each other whose material has the lowest possible friction coefficient, especially a plastic, preferably an optionally fiberglass-reinforced polyethylene, polyamide or the like, in which the glide tube ring is attached to the central tube forming a closed ring that guides/centers this tube in the protecting tube, pipe conduit or the like.
A known glide tube ring of this type is assembled, for example, from two half-shells. Each half-shell on its outside has at least one full glide and two half-glides that are designed as closure strips. The half-shells are positioned around the central tube and screwed together with screws passing through the closure strips and the corresponding nuts. The half-shells are formed and dimensioned so that they can be attached with clamping action on the central tube. A double-coated adhesive strip is often coemployed in smooth central tubes as an adhesive insert.
Glide tube rings of the aforementioned type have been successfully employed for many years. The radii of the half-shells are dimensioned here so that the glide tube ring formed in each case from two half-shells can be used with several central tube outside diameters; for example
______________________________________Nominal width 20 Tube outside diameter of min. 29 to max. 37 mmNominal width 50 Tube outside diameter of min. 60 to max. 67 mmNominal width 100 Tube outside diameter of min. 106 to max. 120 mmNominal width 300 Tube outside diameter of min. 326 to max. 350 mm______________________________________
In practice a wide variety of ridge heights are required in addition to the individual central tube outside diameters, for example
16, 24, 36, 48, 55, 70, 90, 110 mm, so that a higher cost must be incurred for production and maintenance of the corresponding injection molds. Owing to the need to cover several tube outside diameters with the same half-shell radius in conjunction with the requirement of absolute bearing capacity of the glide tube ring, it happens that the inside of the glide tube ring does not lie exactly against the outside of the tube so that thin-walled tubes in particular and tubes made of softer materials, say, plastic tubes, can be deformed in the region of the glide tube ring, which can have adverse effects.
In another known plastic glide tube the number of actually required injection molds is dealt with by constructing two segments with different radii in which the chord length of the large segment is twice as large as that of the small segment. In this fashion it is possible to cover the nominal widths of 100 to 150 (tube outside diameters of min. 98 to max. 215 mm) with a different number of small segments, whereas the large segments are used in the nominal widths of 200 to 350 (tube outside diameters min. 203 to max. 425 mm), in which case a small segment is added to the corresponding number of large segments for the nominal widths of 250, 300 and 350.
The number of required injection molds is indeed reduced in the aforementioned fashion, but the different ridge heights required in practice still invariably result in very high mold cost. Moreover, even when these tested glide tube rings are used, deformation of thin-walled or relatively soft tubes cannot always be prevented; coemployment of adhesive inserts often cannot be dispensed with either.
The segments of the aforementioned very stable plastic glide tube rings are assembled into a ring by means of screws and nuts and attached to the central tube. This is not always so simple at the construction site, especially in cold or wet weather. In addition, the presence of metal in the annular space between the central tube and protecting tube, pipe conduit or the like is not desired, especially when cathodic corrosion protection is to be guaranteed. In another known glide tube ring two segments of different size are again used, but the segments have wedge-shaped closure strips on both sides, in which the wedge members on the closure strips of two neighboring segments are abutted so that the segments are joined, closed into a ring and fastened to the central tube under tension, optionally with the aid of a clamping device and/or adhesive inserts.
Even in this glide tube ring it is often discernible that the segments do not lie against the central tube with sufficient accuracy with the already described consequences; the high cost for manufacture and maintenance of the molds could not be reduced either.
In another known plastic glide tube ring individual segments provided with meshing extensions are lined up on two tightening straps in order to be arranged around the central tube and attached to it by tightening the tightening straps via turnbuckles on the central tube. Three different segments are used here, in which several identical segments are assembled into a glide tube ring and each segment covers a defined tube outside diameter range. Relatively good fit to the outside periphery of the central tube is indeed achieved in this glide tube ring, but the cost for manufacture and maintenance of the molds rises relative to the glide tube rings already mentioned, especially since each segment must be manufactured with a number of very different ridge heights. Moreover, the stability of the glide tube ring so formed is not absolutely guaranteed, especially at larger ridge heights.
In another design of a glide tube ring three different segment types are available for assembly of the glides, in which each segment is allocated to a specific central tube diameter group. A common feature of the three segments is that they consist of a relatively thin-walled plastic so that the segments acquire high flexibility and adjust well to the outside periphery of the central tube. The individual elements are provided with teeth on the top on one end and on the bottom on the other end, by means of which the segments of the same type forming a ring can be inserted one in the other. The still open ring is placed around the central tube and closed by fitting together the two ends. Each segment connection is then tightened with a special tightening tool and the ring fastened to the central tube firmly, if necessary, with coemployment of an adhesive insert. The actual glides in this design are divided into several glide nubs arranged in sequence in the longitudinal direction of the tube, in which the nubs of one row are connected to each other by a thin ridge.
The relatively thin-walled plastic segments do produce high flexibility, but also limit the possible ridge heights. Moreover, bending of the glide nubs could be observed, especially in long tube stretches. Another drawback is that a specific tightening tool must be used for each segment type and the ring position can no longer be corrected after tightening of the segments unless one destroys the ring.
Another glide tube ring is also formed by a screwless, metal-free plug-in connection of individual segments. This differs from the glide tube ring just described in that each glide tube segment has a tongue-like bracket on one side with sawtooth-shaped grooves on its back side. The front half of the bracket penetrates a slit provided in the glide ridge of the neighboring segment, in which the segments are provided with sawtooth-shaped grooves on their top corresponding to those of the bracket. In order to form the glide tube ring the individual segments are fitted together via the brackets so that falling apart of the individual segments is prevented by barbs applied to each bracket. The open glide tube ring so formed is now placed loosely around the product tube and the individual segments are easily interlocked. Each connection point is then tightened with a special tightening tool until the glide tube ring is firmly attached to the central tube.
Whereas the previously described glide tube ring is supposed to be employable from a central tube outside diameter of 59 mm, the glide tube ring just described is only applicable from a central tube outside diameter of 130 mm. A common feature of both glide tube rings is that loosening of the glide tube ring when the ring position is incorrect is only possible by destruction of an individual segment.
Another glide tube ring that has relatively rigid, black individual segments with screwless, metal-free plug-in connection profits from the two glide tube rings just described. Each individual segment is provided with a fastening bracket on one side having two serrated slats on the top in the peripheral direction and barbs on the bottom in the region of its front limitation. The fastening bracket and the half of the individual segment form the tube support surface, whereas the other segment half is designed so that the fastening bracket can pass beneath it. The end of the individual segment that is passed underneath has a transverse opening with a number of ridges congruent to the barbs of the fastening bracket and two serrated counterslats on its bottom corresponding to the serrated slats of the fastening bracket. The individual segments joined in the aforementioned fashion are now tightened by means of a plastic flat bar. This occurs in that both the fastening bracket and the segment part that it passes beneath have slit-shaped openings on the side that are offset relative to each other. Wedge-shaped guide slats that take up the flat bar with simultaneous tightening of the individual segments run along these openings. During this tightening the barbs of the fastening brackets are firmly locked in the transverse ridges of the segment part that is passed beneath.
In contrast to the two glide tube rings just described, in this glide tube ring a tightening tool is only required for closure of the glide tube ring, since the other individual segments are already tightened by the flat bar. This could be an advantage from an installation standpoint. However, the drawback is that the last plug-in connection must take up the entire tensile stress required for firm seating of the glide tube ring on the central tube. This could mean, especially in large and heavy central tubes, that even limited tilting during insertion of the central tube into the protecting tube or pipe conduit will cause rupture of the last plug-in connection with all the consequences stemming from this. This hazard increases with an increase in glide-ridge height.
Finally, a glide tube ring that can be assembled from individual segments is known whose segments are produced without glides and provided with glides of a certain ridge height so that glide shoes with corresponding ridge height are pushed through from the inside of the segment into longitudinal openings made in it and stopped.
A reduction of mold cost can be achieved in this glide tube ring, but a drawback is that the weight of the central tube and of the medium is not taken up by a large surface, but only by the small surface of the glide shoe; this bearing surface is extremely small in hollow glide shoes.
The underlying objective of the invention is to devise a glide tube ring that is designed in one part, optionally two, three or more parts, has a very high degree of flexibility with high stability, is easy to install, contains no metal parts and in which the cost for manufacture and maintenance of the molds can be minimized. Another objective of the invention is to point out the materials from which the glide tube ring according to the invention is to be manufactured; at the same time the invention is to demonstrate the process for manufacturing the glide tube ring according to the invention and to offer information concerning the devices with which the glide tube ring according to the invention or the glide tube ring segments according to the invention are produced.
The invention accomplishes this task in a glide tube ring of the type described in the introduction in that the glide tube ring consists of an elastic, flexible, expandable, preferably recoverable, especially strip- or tire-like, rubber-elastic body, that the top of the body has a number of ribs running across its longitudinal direction arranged parallel to each other with spacing, in which the spacing of the ribs is as defined as their cross-sectional shape, height, width and length, that glide shoes with the ridge height according to requirements can be mounted on the ribs, preferably in undetachable fashion and the material of the body has a high friction coefficient, say, consists of an elastomer according to DIN 7724, for example, EPDM, SBR, NR, CR, NBR or the like, which is optionally provided with an antiscorching agent and/or an activator, if necessary, modified with carboranes.
A glide tube ring designed in this fashion is formed in one layer, two layers or several layers according to the invention, the layers consisting of a two- or multilayered glide tube ring from the same, same type of, similar or different materials are connected preferably undetachably, especially with application of heat and/or pressure, optionally with coemployment of two or more adhesion promoters, the layers have the same or different coefficient(s) of linear expansion and the layer that has the highest coefficient of expansion forms the top of the body, whereas the layer with the smallest expansion coefficient forms either the bottom of the body or the middle layer and is then the longitudinal expansion limiter of the other layers.
The ribs according to the invention preferably consist of the material of the one-layered body or, in multilayered bodies, preferably of the material of the upper layer and are molded onto the body or molded into it and form a single whole with the body. The ribs can be stiffened, for example, by embedded profile rods that preferably consist of a nonconducting material, for example, plastic, especially fiberglass-reinforced plastic, a rubber-elastic material of high Shore hardness or the like, in which the ribs preferably have a trapezoidal cross section in both the longitudinal direction of the body and across it and optionally grade into a straight-rectangular part in the upper part. Glide shoes with selectable ridge heights according to requirements can be mounted on these ribs and are preferably joinable using heat and/or pressure, optionally with coemployment of an adhesion promoter, or mechanically.
The invention also proposes that in a one-layered body its ribs are replaced by support slats that can be mounted on the top of the body and joined to it. The support slats here preferably consist of a nonconductive material, for example, a plastic that is optionally fiberglass-reinforced and/or UV-stabilized, an elastomer with particularly high Shore hardness or the like, in which the support slats are joinable to the body by a vulcanization and/or welding process, especially using heat and/or pressure, optionally with coemployment of an adhesion promoter. Here again the support slats are preferably designed trapezoidal in cross section both in the longitudinal direction of the body and across it and optionally grade into a straight, rectangular part in the upper part.
Glide shoes with selectable ridge heights can be mounted on the ribs or support slats and are permanently joinable to them mechanically or via a vulcanization and/or welding process using heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like. For this purpose the glide shoes have a cavity on their lower part congruent in shape and size to the ribs or support slats. The glide shoes can consist, for example, of a high-density polyethylene into which coloring pigments are optionally admixed. The cavity of the glide shoe can be smaller by a selectable amount than the spatial shape of the ribs or support slats, this amount being chosen from the standpoint of the so-called memory effect of the material used to manufacture the glide shoe. The polyethylene of the glide shoe can be chemically crosslinked to improve wear resistance and the glide shoes can likewise be surface-crosslinked, especially radiation-crosslinked and consist of solid material in their upper part.
The glide shoes can also be joinable according to the invention mechanically, preferably undetachably so that one, two or more expansion anchors can be arranged in the cavity of each glide shoe, which can be pressed claw-like into the opening of the ribs or support slats. The expansion anchors arranged in the cavity of the glide shoe are either rigidly joined to the glide shoe and form a single whole with it, or are produced separately and subsequently inserted in the openings arranged in each glide shoe. For this purpose the invention proposes that the expansion anchors be either insertable with the application of heat and/or pressure, optionally with application of a coating, if necessary, with coemployment of an adhesion promoter, or in the openings of the glide shoe so that the openings arranged in the glide shoes are widened mechanically and/or with the use heat, the expansion anchors are inserted into the widened openings and fastened here with recovery of the expansion.
A glide tube ring designed in this fashion is a one-part body according to the invention that is a defined section of a body strip wound into a roll, in which the stretched, unstressed length of the section is shorter by a predetermined amount than the outside periphery of the central tube to be inserted with the glide tube ring. In this case the stretched, unstressed length of the defined section can be set at a predetermined size, allowing for the initial thickness of the body strip and limitation of its linear expansion coefficient so that the glide tube ring so formed can be applied to two, three or more central tubes of different outside diameter under tensile stress, where the tensile stress is preferably great enough so that the position of the glide tube ring on the central tube, once chosen, cannot be changed or can be changed only insignificantly during its insertion into the protecting tube, the pipe conduit or the like.
According to another characteristic of the invention the glide tube ring is designed in two or more parts and can be assembled from two or more body segments, where the body segment is another defined section of the body strip wound into a roll and its stretched, unstressed length is shorter by a predetermined amount than the outside peripheral part of the central tube to be inserted with the two- or multipart glide tube ring corresponding to the section. In this case the stretched, unstressed length of the body segment can be set at a predetermined value, allowing for the initial thickness of the body strip and limitation of its linear expansion coefficient so that the glide tube ring assembled from two or more body segments can be applied to two, three or more central tubes of different outside diameter and the tensile stress is preferably great enough so that the position of the glide tube ring on the central tube, once chosen, cannot be changed or can be changed only insignificantly so during its insertion into the protecting tube, pipe conduit or the like.
According to another characteristic of the invention closures can be allocated to the two ends of the one-part body, as well as to the two ends of each body segment, and joined to them, preferably by heat and/or pressure, optionally with coemployment of an adhesion promoter. The closures that can be allocated to the body or body segments can be slats having lugs provided with eyes, which are designed so that the lugs of neighboring slats interlock and, lying outside of the support surface of the central tube in the installed state, can be penetrated by a rod, joining the bodies into a closed glide tube ring or joining the body segments forming a two- or multipart glide tube ring, so that sleeves that stiffen the lugs, optionally forming eyes, are embedded in the lugs, preferably consisting of a nonconducting, especially high-strength material, whereas the lugs and slats are formed either from the material of the body or consist of a plastic, preferably a fiberglass-reinforced polyethylene, polyamide or the like.
According to another variant of the invention the closures are screw slats provided with openings, formed so that in the installed state they lie outside of the support surface of the central tube and the openings of the screw slats can be penetrated by screws that join the body into a closed glide tube ring or join the body segments that form a two- or multipart glide tube ring. It is also prescribed that the closures are wedged slats that can mesh with wedges formed so that in the installed state, lying outside of the support surface of the central tube, they can be wedged by means of two facing wedges that join the body into a closed glide tube ring or join the body segments that form a two- or multipart glide tube ring. The back side of the closure made of plastic can be allocated to a support surface that consists, for example, of the material of the body and can be joined to the closures, especially with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, and that the closures provided with the support surface can be joined to the ends of the one-part body or those of the body segments by a vulcanization process or a welding process, if necessary, with reuse of heat and/or pressure, optionally with coemployment of an adhesion promoter.
According to the invention the glide shoes can also consist of a high-density polyethylene (HDPE), a polyethylene terephthalate (PETP), a polybutylene terephthalate (PBTP) or the like, a polyester based on ethylene glycol and 2,6-naphthalenecarboxylic acid, a polyarylate based on, for example, diphenols and aromatic dicarboxylic acids or a polyester based on a 3-hydroxybenzoic acid as homogeneous monomer.
It is prescribed according to another characteristic of the invention that the Shore hardness of the ribs deviates from that of the one-layered body or from that of the upper layer of the two- or multilayered body, where the Shore hardness of the ribs is preferably greater.
The body can also consist of a thermoplastic, for example, PVC, EVA or the like, which has sufficient rubber elasticity and a high friction coefficient.
The invention also points out that the body can also consist of a thermoplastic elastomer, for example, a TPO, SBS, SEBS or the like, which has sufficient rubber elasticity and a high friction coefficient. For example, the thermoplastic elastomer can be plasticized and mixed, then molded, vulcanized and tempered with addition of fillers, acid acceptors, vulcanization accelerators, vulcanizers, optionally with coemployment of activators.
It is also prescribed that the body preferably consists of a natural rubber, in which the strip-like or tire-like, endless body can be provided on one side with a coating that can be made reactive so that a vulcanization process and/or a welding process can be initiated in it by controlled application of heat and/or pressure, through which it is joinable to both the body and to the support slats undetachably applied to it into a rollable unit. For this purpose the body of defined width can be laminated with the coating either over its entire surface, partially or in strips, optionally in the fashion of a herringbone pattern, a diamond pattern or the like.
In a two- or multilayered body the coating according to the invention can be arranged between the layers and especially is undetachably joinable to them, preferably with application of heat and/or pressure.
The back side of the closure can also be laminated with the coating in such a way that a partial reaction can be initiated in the coating by controllable application of heat and/or pressure, through which the coating can be made to adhere to the bottom of the closure, preferably undetachably. The closures can now be placed on the two ends of a one-part glide tube ring or on the ends of each body segment of a two- or multipart glide tube ring, whereupon a final reaction can be initiated in the coating by controlled application of renewed heat and/or pressure, through which the closures are joinable undetachably to the coating and this is joinable undetachably to the ends of the one-part glide tube ring or the ends of each body segment of a two- or multipart glide tube ring.
The coating according to the invention can also be applied to the expansion anchor and a partial reaction initiated in it by controlled application of heat and/or pressure, through which it is undetachably fixed to the expansion anchor, in which case after insertion of the expansion anchor provided with the coating into the openings of the glide shoe the residual reaction can be initiated in the coating with renewed controlled application of heat and/or pressure, through which the expansion anchors are undetachably joined to the coating and the coating joined to the walls of the openings of the glide shoe.
According to a process characteristic, a one-part glide tube ring having a single closure can be produced by incorporating ribs or support slats of defined size and shape at a defined parallel spacing, optionally with stiffening by incorporation of appropriately shaped profile rods or the like across its longitudinal direction by molding them into, onto or joining them on one side in an endless, elastic, flexible, stretchable, especially recoverable, strip-like or tire-like, rubber-elastic body of defined width formed in one, two or several layers. The body provided with ribs or support slats is wound into a roll for storage purposes and partial lengths or sections are unwound from this as required and cut off, the length of which is shorter by a predetermined value than the outside periphery of the central tube being inserted with the glide tube rings. The partial lengths or sections are then fashioned into one-part, open glide tube strips by providing the two ends of the section with congruent closure slats and joined to them undetachably, especially by means of a vulcanization or welding process. Plastic glide shoes with the required ridge height are then mounted on the ribs or support slats of the one-part glide tube strips and joined to them, preferably undetachably, especially by means of a vulcanization or welding process, optionally mechanically. The one-part, open glide tube strips so produced are placed around the central tube at predetermined points and formed into a one-part glide tube ring having a single closure so that the closure slats are converted into single closures with application of a tensile stress by means of a rod or by means of two screws with the corresponding nuts or by means of two wedges.
According to another process characteristic, a two-, three- or multipart glide tube ring having two, three or more closures can be produced by incorporating ribs or support slats of defined size and shape in a defined parallel spacing, optionally with stiffening by incorporation of appropriately shaped profile rods or the like, by molding them into, onto or joining them on one side across its longitudinal direction in an endless, elastic, flexible, stretchable, especially recoverable, strip-like or tire-like, rubber-elastic body of defined width formed in one, two or several layers. The bodies provided with ribs or support slats are wound into a roll for storage purposes and a number of partial lengths or sections corresponding to the required ring parts are unwound from this and cut off, the length of which is shorter by a predetermined value than the corresponding outside partial periphery of the central tube being inserted with the glide tube rings. The partial lengths or sections are then fashioned into glide tube segments by providing the two ends of each section with congruent closure slats and joining the ends to these, preferably undetachably, by means of a vulcanization or welding process. Plastic glide shoes with the required ridge height are then mounted on the ribs or support slats and joined to them, preferably undetachably, especially by means of a vulcanization or welding process, optionally mechanically. The glide tube segments so fabricated are then assembled at the construction site to open glide tube segment strips by connecting the closures of neighboring glide tube segments together with a rod, two screws with the corresponding nuts or two wedges. The glide tube segment strips so formed are then placed around the central tube at predetermined sites and formed into multipart glide tube rings having several closures by converting the last two closure slats of each segment strip to a closure with application of tensile stress by means of a rod or by means of two screws with the corresponding nuts or by means of two wedges.
Another process characteristic states that an endless, elastic, flexible, stretchable, especially recoverable, rubber-elastic body of defined width is heated and ribs running parallel to each other with defined spacing are formed on its back side across its longitudinal direction, that the material of the body is either accumulated on the sites of the body prescribed for rib production, especially by application of pressure, optionally with additional heat supply, compressed, and the desired rib shape and size are formed accordingly, or the body is creased across its longitudinal direction at defined spacing, profile rods, especially those made from a nonconducting material, are optionally inserted in these creases and the creases are sealed, preferably with repeated heat supply and pressure, optionally with coemployment of an adhesion promoter, and the profile rod incorporated by vulcanization. The body so equipped with ribs is wound into a roll for storage purposes, from which a defined section is cut off as required for a one-part glide tube ting or two or more defined other sections are cut off for a two- or multipart glide tube ring. The ribs of the section are now preferably heated and glide shoes with the required ridge height are mounted on these and joined undetachably to the ribs with application of pressure and possibly renewed heat supply, optionally with coemployment of an adhesion promoter. Each end of the section is then provided with a closure by mounting the closures with their bottom on the top of the ends of the section and joined together undetachably, preferably under pressure and possibly renewed heat supply, optionally with coemployment of an adhesion promoter, during which a reactive coating is applied beforehand to the bottom of the closure, especially using heat and/or pressure, optionally with coemployment of an adhesion promoter, and then either the one-part body so formed is placed around the central tube and the body closed via the two closures by means of a rod, two screws with corresponding nuts or by means of two wedges into a one-part glide tube ring and attached to the central tube under tensile stress, or the body segments provided with closures are joined by means of a rod, two screws with corresponding nuts or two wedges and formed into an open segment strip, this is placed around the central tube and the two- or multipart glide tube ring is formed on making the last connection and fastened to the central tube under tensile stress.
The invention states according to another process characteristic that an endless, elastic, flexible, stretchable, especially recoverable, rubber-elastic body of defined width is unwound from a supply roll and fed to a calender, that the body is heated on the top on its way to the calender and provided with an adhesion promoter, a vulcanization accelerator, an activator or the like and profile rods are fastened to the so prepared surface at a defined parallel spacing from each other across the longitudinal direction of the body. In the meantime another endless, elastic, flexible, stretchable, especially recoverable, rubber-elastic body of defined width is unwound from another supply roll and also fed to the calender, during this process the second body is preferably also heated on its bottom on its way to the calender and optionally treated with an adhesion promoter, a vulcanization accelerator, an activator or the like, that the bodies so prepared are brought together in the calender and both bodies are joined together with inclusion of the profile rods attached to the bodies with application of pressure and optionally renewed heat supply in such a way that an endless, elastic, flexible, stretchable, especially recoverable, rubber-elastic, two-layered body provided with stiffened ribs is obtained, which is wound onto a roll for storage purposes, from which a defined section is unwound and cut off as required for a one-part glide tube ring or two or more other sections are cut off for a two- or multipart glide tube ring. The ribs of the section are preferably heated and glide shoes with the required ridge height are mounted on them with application of pressure and possibly renewed heat supply, optionally with coemployment of an adhesion promoter, during which process the ends of the section are then each provided with a closure, the closures are mounted with their bottom on the top of the ends of the section and joined together, preferably under pressure and possibly renewed heat supply, optionally with coemployment of an adhesion promoter, especially undetachably, and, if necessary, a reactive coating is joined to the bottom of the closure, especially using heat and/or pressure, optionally with coemployment of an adhesion promoter. In this case either the one-part body so formed is positioned around the central tube and the body closed via the two closures by means of a rod, two screws with corresponding nuts or by means of two wedges into a glide tube ring and attached to the central tube under tensile stress, or the body segments provided with closures are each joined by means of a rod, two screws with corresponding nuts or two wedges into an open segment strip, which is placed around the central tube, and the two- or multipart glide tube ring is formed on making the last connection and attached to the central tube under tensile stress.
An essential characteristic of the invention here is that both the stiffened and unstiffened ribs are formed so that on conclusion of the vulcanization process a unified whole is formed with both the one-layered and the two- or multilayered bodies. For this purpose heat supply and/or pressure is controlled in a one-layered body in the region of the stiffening ribs on the side of the body facing away from the ribs in variable fashion so that a higher degree of plasticization of the body material is partially established and melting of the material occurs in the region of original formation of the creases so that a homogeneous, uniform whole is also achieved in the region of the original creases and the side of the body facing away from the ribs forms a closed surface.
The ribs are formed either over the entire defined width of the body or the length of the ribs and/or profile rods is limited so that defined guide edges are obtained on both long edges of the body by means of which the body is fed in controlled fashion to the calender and controllably advanced through this.
Profile rods whose cross-sectional shape is congruent to the desired cross-sectional shape of the ribs are used for stiffening of the ribs, during which heat supply and pressure on the side of the body facing the ribs is controlled so that a higher degree of plasticization of the body material is achieved in the region of rib formation.
In a multilayered body an additional layer is arranged according to the invention between two layers as a central layer and this is joined to the other layers with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator and/or an activator, in which process the central layer is given a linear expansion coefficient that limits the possible linear expansion of the other layers to 10 to 90%, preferably 25 to 70%. Dispensing with incorporation of the middle layer by vulcanization, this can also be vulcanized or welded onto the lower layer. It is also prescribed that the layers be joined simultaneously with formation of ribs and that the linear expansion coefficient of the one-, two- or multilayered body be defined as a function of the corresponding Shore hardness.
According to the invention the ribs are preferably replaced in a one-layered body with support slats, on which the support slats are mounted at a parallel, defined spacing on the top of the body and joined to it. The support slats are preferably formed from a nonconducting material, for example, from a plastic that is optionally fiberglass-reinforced and/or UV-stabilized, an elastomer with particularly high Shore hardness or the like, placed on the top of the body and joined to it by a vulcanization and/or welding process, especially with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like.
In addition, the invention proposes that the ribs or support slats be formed preferably trapezoidal both in the longitudinal direction of the body and across it, the trapezoidal cross section optionally grading into a straight, rectangular part in its upper part, that the glide shoe be provided in its lower part with a cavity that corresponds in shape and size to the ribs or support slats and that the glide shoe so formed be mounted with its cavities on the ribs or support slats and joined to them, preferably undetachably, the glide shoe being joined to the ribs or support slats preferably with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like.
The glide shoe is formed according to the invention, for example, from an optionally fiberglass-reinforced, if necessary, UV-stabilized polyethylene, in which the cavity of the glide shoe is made smaller by a predetermined amount than the ribs or support slats, the cavity of the glide shoe is then heated so that it acquires the shape and size of the ribs or support slats, preferably becomes larger by a defined amount and the glide shoe so treated is mounted with its cavity on the ribs or support slats and fastened or shrunk onto the ribs or support slats by restoring the heat-produced elongation of the cavity to its original value.
According to another process the invention proposes that the glide shoe be mechanically joined to the ribs or support slats. For this purpose the ribs or support slats are provided with one, two or more openings, a corresponding number of expansion anchors is arranged in the cavity of each glide shoe and the expansion anchors are pressed or driven into the openings so that they are engaged claw-like in the walls of the openings, preferably undetachably. The expansion anchors are formed during production of the glide shoe simultaneously with formation of the cavities in them, so that they form a single whole with the glide shoe.
According to another embodiment, openings are made in the cavities of the glide shoe whose shape and cross-sectional size correspond to the shape of the expansion anchor, in which process the expansion anchor is produced separately and inserted, preferably undetachably, into the openings of the glide shoe so that the expansion anchor is fastened in the openings with application of heat and/or pressure, optionally with application of a coating beforehand onto the corresponding part of the expansion anchor shaft, if necessary with coemployment of an adhesion promoter, or the openings are expanded mechanically and/or with application of heat and the expansion anchors are shrunk into the openings with recovery of the expansion.
It is also proposed that the glide shoe be made, for example, from a high-density polyethylene, a coloring pigment be optionally admixed with this and the glide shoe preferably in its upper region be formed from a solid material, in which process the glide shoes in their upper region are given a cross-sectional shape that corresponds in particular to a circular arc section and that the polyethylene be either chemically crosslinked in known fashion beforehand or subsequently surface-crosslinked, especially radiation-crosslinked, to improve its wear resistance.
It is also prescribed that a crude rubber blend consisting of natural rubber, fillers, accelerators and vulcanizers be formed and vulcanized, optionally with coemployment of activators, into an endless, elastic, flexible, stretchable, preferably recoverable, especially strip-like or tire-like body having ribs on one side of defined number, shape, size and arrangement and that the body so formed be wound into a roll (7) for storage purposes.
It is also possible according to the invention to produce the body from a thermoplastic, for example, from PVC, EVA or the like, which is given sufficient rubber elasticity and a high friction coefficient.
It is also proposed according to the invention that the body be produced from a thermoplastic elastomer, for example, a TPO, SBS, SEBS or the like, and that carboranes or other products that increase temperature resistance, as well as an antiscorching agent, optionally be added. It is also proposed that the body be laminated on one side, especially on its top, with a coating that is kept reactive so that a vulcanization and/or welding process is initiated in it by controlled application of heat and/or pressure and that the coating be joined undetachably into a windable unit in this fashion both to the body and to the support slats mounted on it. It is proposed here that the endless body of defined width be laminated with the coating over its entire surface, partially or in strips, optionally in the fashion of a herringbone pattern, a diamond pattern or the like.
The invention also proposes that the back side of the closures be laminated with the coating under controllable application of heat and/or pressure by initiating a partial reaction in the coating that is sufficient to cause the coating to adhere undetachably to the back side of the closure and that the closures so provided with the coating be stored for later fabrication of the one-, two-, three- or multipart glide tube ring.
It is proposed according to another process that a number of sections be unwound and cut off from the stored roll as prefabrication for production of one-part glide tube rings, that a closure provided with the coating be mounted on the two ends of each section, and that the residual reaction be initiated in the coating by controllable application of heat and pressure, the closures joined undetachably to the coating and this undetachably to the section and that the fabricated, one-part bodies be stockpiled.
It is also proposed that for production of two-, three- or multipart glide tube rings as prefabrication a number of sections, each of which is a body segment, be unwound from a stored roll and cut off, that a closure provided with the coating be mounted on each end of a body segment and that the residual reaction be initiated in the coating by controllable application of heat and pressure, the closure joined undetachably to the coating and this undetachably to the ends of the body segments (2a) and that the so fabricated body segment be stockpiled.
Another process characteristics demonstrates that an endless, elastic, flexible, stretchable, especially recoverable, strip-like or tire-like, rubber-elastic body (1) of defined width is unwound from a supply roll (27a) and fed to a calender (28) or the like, that a coating (24a) is unwound from another supply roll (27c) and also fed to the calender (28) or the like, that the top of the body (1) and/or the back side of the coating (24a) is heated and/or provided with an adhesion promoter, a vulcanization accelerator, an activator or the like on the way to calender (28) or the like, that the coating (24a) is laminated between rolls (28a, 28b) of calender (28) over the entire surface, partially or in the fashion of a herringbone pattern, a diamond pattern or the like, preferably with application of pressure, if necessary, with renewed heat supply, onto the surface of body (1), especially undetachably, that support slats (3a) are arranged on the coating (24a) laminated onto body (1) at a parallel, defined spacing from each other and these are joined, for example, in a pressing device (33) or the like, optionally with renewed heat supply, with application of pressure, especially undetachably, to coating (24a) and the body (1) provided in this fashion with support slats (3a) is wound onto a roll (7) as an endless body strip (8) for storage purposes.
According to another process characteristic it is obvious that an endless, elastic, flexible, stretchable, especially recoverable, strip-like or tire-like, rubber-elastic body (1) of defined width is unwound from a supply roll (27a) and fed to a calender (28) or the like, that a coating (24a) is unwound from another supply roll (27c) and also fed to the calender (28) or the like, that the top of the body (1) and/or the back side of the coating (24a) is heated and/or provided with an adhesion promoter, a vulcanization accelerator, an activator or the like on the way to calender (28) or the like, that the coating (24a) is laminated between rolls (28a, 28b) of the calender (28), especially undetachably, onto the surface of body (1) over its entire surface, partially or in the fashion of a herringbone pattern, a diamond pattern or the like, preferably with application of pressure, if necessary with renewed heat supply, that profile rods (5) are arranged in a parallel, defined spacing from each other on the coating (24a) laminated onto body (1), that another elastic, flexible, stretchable, especially recoverable, strip-like or-tire-like, rubber-elastic body (2) is unwound from another supply roll (27b), heated on its back side and/or provided with an adhesion promoter, a vulcanization accelerator, an activator or the like and introduced together with the body (1) provided with coating (24a) and profile rods (5) into a pressing device (33) or the like and that both bodies (1, 2) are joined into a preferably undetachable unit with inclusion of the profile rods (5) via coating (24a) with application of pressure and optionally renewed heat supply and the two- or three-layered body (1/2) so formed is wound into a roll (7a) for storage purposes.
Additional embodiments of the invention can be gleaned from the patent claims and the description of the drawings:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a glide tube ring according to one embodiment of the invention;
FIG. 1A is a perspective view, on an enlarged scale, of a part of the glide tube ring as generally indicated by the phantom circle 1A in FIG. 1;
FIG. 2 is a perspective view of a glide tube ring, like FIG. 1 but illustrating a modified construction;
FIGS. 3a, 3b and 3c are detail views, on an enlarged scale, illustrating different closure devices usable in the glide tube rings of FIGS. 1 and 2;
FIGS. 4, 5 and 6 are elevation views of portions of plural segment glide tube rings using the closure devices of FIGS. 3a, 3b and 3c, respectively;
FIG. 7 is a schematic elevation view used to describe and illustrate one method of manufacture according to the invention;
FIG. 8 is a side elevation view of a single-segment glide tube ring constructed in accordance with the invention;
FIG. 9 is a side elevation view of a plural segment glide tube ring similar to that of FIG. 8;
FIG. 10 is a schematic elevation view used to describe and illustrate a further method of manufacture according to the invention;
FIG. 11 is a detail side elevation view of a composite strip used to construct glide tube rings according to the invention;
FIG. 12a is a sectional view of a guide shoe for use in the invention;
FIG. 12b is a sectional view like FIG. 12a but showing a different guide shoe construction; and
FIG. 13 is a schematic elevation view, similar to FIG. 10, of another manufacturing method according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a one-part glide tube ring 1 (26) provided with a number of ribs 3, which is a defined section 6 of an elastic, flexible, stretchable, preferably recoverable, especially strip-like or tire-like, rubber-elastic body strip 8 wound into a roll 7, whose stretched, unstressed length is shorter by a predetermined amount than the outside periphery of the central tube 9 to be inserted with a glide tube ring. Both ends of section 6 are provided with a closures 11, to which each closure 11 is joined, especially undetachably, to the body 1 with application of heat and/or pressure, optionally with coemployment of an adhesion promoter. The congruent closures 11 have a slat 16 with lugs 14 formed on it, which are provided with eyes 15 penetrated by a rod 17 to form the single closure; in this case the eyes 15 of lugs 14 can be reinforced by sleeves 18. The back side of slat 16 can be laminated with a coating 24 that is joined, preferably undetachably, to slat 16 by means of a vulcanization and/or welding process. Lamination occurs according to the invention preferably with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like.
The ribs 3 in this rubber-elastic body 1 or glide tube strip 26 consist of the material of the body, are molded onto it or into it and form a uniform whole with body 1. Glide shoes 4 with the required ridge height H are mounted on these ribs 3, as is apparent from FIG. 3.
FIG. 2 shows the section 6 of a rubber-elastic body strip 8 that forms a one-part body 1 forming a one-part glide tube ring which has a single closure in conjunction with the two closures 11 and the rod 17 belonging to them. Dispensing with ribs 3, support slats 3a are applied to this body 1 and joined, preferably undetachably, to the body, especially with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like. The support slats 3a are formed so that they represent either glides with the smallest possible ridge height H, or glide shoes 4 with the required ridge height H are mountable on them (FIG. 3).
The glide tube strip 26 formed from the one-part body 1 or the defined section 6 is placed around central tube 9 at the construction site and closed into a glide tube ring and attached to the central tube preferably under tensile stress by passing a rod 17 through the eyes 15 of lugs 14; the rod 17 forms a hinge closure together with eyes 15 and lugs 14. The rod 17 consists of a-high-strength material, preferably a nonconducting material; for example, it can consist of a plastic, preferably a fiberglass-reinforced, optionally UV-stabilized plastic, and can also be manufactured from a rigid carbon fiber or the like.
In the one-part glide tube ring of FIGS. 1 and 2 the stretched, unstressed length L 1 of body 1 or of defined section 6 of body strip 8 is shorter by a predetermined amount X than the periphery of the central tube 9 to be inserted with the glide tube ring, thus value X can be predetermined as a function of the initial thickness D and linear expansion coefficient of body strip 8. The value X is preferably chosen so that the one-part glide tube ring can be applied to two, three or more central tubes of different diameter under tensile stress, in which the tensile stress is preferably great enough that the position of the glide tube ring on central tube 9, once chosen, is not changed or not significantly so during its insertion into the protecting tube, pipe conduit or the like.
FIG. 3 shows the endless body strip 8 provided with ribs 3 or support slats 3a, which is wound into a roll 7 for storage purposes. If glide tube rings are now required for a central tube 9 with a defined outside diameter, which is to be inserted into a protecting tube with known inside diameter, the procedure is as follows:
a) The central tube is to be provided with one-part glide tube rings. As many sections 6 as glide tube rings are required are unwound from stored roll 7 and cut off. For this purpose the outside periphery of central tube 9 is determined and this quantity reduced by the aforementioned value X; length L 1 is obtained. As many sections 6 as one-part glide tube rings are required are unwound from roll 7 with length L 1 and cut off.
b) The central tube is to be provided with glide tube rings that consist of two, three or more segments. The outside periphery of the central tube is determined and divided by the number of segments per glide tube ring and reduced by value Y; value L 2 is obtained. As many sections 10 as body segments 2a are required with length L 2 are unwound from roll 7 and cut off to produce the required number of two-, three- or multipart glide tube rings.
The sections 6, 10 so obtained are now fabricated each with two congruent closures 11, 12 or 13 according to FIGS. 4a, 4b and c, or differently configured closures.
If glide tube rings whose glides have a ridge height corresponding to the value D+H 1 are required for insertion of the central tube in the protecting tube, a roll 7 is chosen whose body strip 8 is provided with support slats 3a that preferably consist of a plastic with the lowest possible friction coefficient. However, if glide tube rings with higher ridge height are required, the already described body strip 8 with the support slats 3a fastened to it can be used, but also a body strip 8 whose ribs 3 are molded onto body 1, 2 or molded into it, optionally with inclusion of stiffening profile rods 5. Glide shoes 4 with the required ridge height H are mounted on ribs 3 or support slats 3a of the one-part glide tube rings or body segments 2a fabricated with closures 11, 12 or 13 and joined, especially undetachably to ribs 3 or support slats 3a. This can occur in the following fashion:
c) The glide shoes 4 are made from a plastic having the greatest possible recovery. Such glide shoes 4 are preferably provided with a recess 4a whose shape and size is congruent to ribs 3 or support slats 3a, but smaller by a predetermined amount. The recess 4a of glide shoe 4 is now widened mechanically and/or thermally so that the glide shoe 4 with its recess 4a can be easily mounted onto ribs 3 or support slats 3a; the recesses 4a regain their original dimensions and thus shrink undetachably onto ribs 3 or support slats 4a (FIG. 12a).
d) The ribs 3 or support slats 3a are provided with openings 31 into which expansion anchors 30, which are arranged in the recesses 4a of glide shoe 4, interlock (FIG. 12b). The expansion anchors 30 can be produced either simultaneously with glide shoes 4 and form a single whole with them, or they are produced in their own device and inserted into openings 32 provided in the recesses 4a of glide shoe 4 (FIG. 12c). In the latter case the expansion anchors 30 are undetachably fixed in the openings 32 of recesses 4a either by exploiting the memory effect described under 3.c, or the expansion anchor 30 is provided with a coating 24a in its upper part and joined, especially undetachably, to it with application of heat and/or pressure, optionally with coemployment of an adhesion promoter, inserted into opening 32 of recess 4a with the part characterized by coating 24a and fastened here, possibly with renewed heat supply and/or pressure, optionally with coemployment of an adhesion promoter.
e) The surface of ribs 3 or that of support slats 3a is provided with a coating 24a and joined to it, preferably with application of heat and/or pressure, especially undetachably, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like. The glide shoes 4 are mounted via their recesses 4a onto the ribs 3 or support slats 3a so prepared and joined to them undetachably via coating 24a with possible renewed heat supply and/or pressure.
The aforementioned methods can also be combined according to the invention.
FIG. 4 shows three possible closure or connection pieces 11, 12 and 13; differently configured connection and closures are also conceivable. The connection or closure 11 (FIG. 4a) has already been described at length under FIG. 1. The connection or closure 12 has a screw slat 19 with two, three or more openings 20 that can be penetrated by screws 21. The screw slats 19 are formed so that they lie in the installed state outside of the support surface of the central tube. In a one-part glide tube ring the screw slats 19 with the screws 21 penetrating their openings 20 with the corresponding nuts 21a form the only closure via which the one-part glide tube ring is attached to the central tube under tensile stress.
In a glide tube ring assembled from two, three or more body segments 2a the screw slats 19 of two neighboring body segments 2a each form a closure through which a segment strip 26a is formed that is loosely placed around the central tube and closed into a glide tube ring by forming the last two screw slats 19 into a closure still not connected together by the corresponding screws 21 and nuts 21a, and the glide tube ring can be attached to the central tube under tensile stress by uniform tightening of all screws 21 (FIG. 4b).
Wedge slats 22 of connection or closure 13 can also be used instead of screw slats 19, in which case two facing wedges in each case produce the connection or closure (FIG. 4c).
FIGS. 5, 6 and 7 show the already described closures 11, 12 and 13 as connection pieces in segment strips 26a assembled from two, three or more, rubber-elastic body segments 2a.
FIG. 8 shows a segment strip 26a consisting of three body segments 2a with allocated closure or connection pieces 11, in which each rubber-elastic body segment 2a has only one rib 3 or only one support slat 3a; glide shoes 4 can be mounted undetachably according to requirements as already described. The hinged, rubber-elastic segment strip is positioned around central tube 9 at the construction site on the location prescribed for it and closed into a three-part glide tube ring by bringing together the still unconnected closures 11, utilizing the stretchability of the rubber-elastic body segments 2a and producing the closure (shown in FIGS. 1 and 2) by means of a rod (not shown) so that the now closed glide tube ring is attached to central tube 9 under tensile stress.
FIG. 9 shows the same situation in a one-part body 1 that is formed into a body strip 26 by congruent closures on its two ends. Here again the one-part body strip 26 is placed around central tube 9 at the construction site on the location prescribed for it and the now closed, one-part glide tube ring fastened to central tube 9 under tensile stress by connecting the two closures 11 by means of a rod 17 not shown (FIGS. 1 and 2).
FIG. 10 shows a possible process with the corresponding device for producing an endless, rubber-elastic body strip 8a with stiffened, molded ribs 3. A rubber-elastic, endless body 1 is unwound from a supply roll 27a and fed to a calender 28, in which the top of the body 1 is heated and profile rods 5 are fastened at a defined spacing from each other on the surface so prepared. Another rubber-elastic body 2 is unwound from a second supply roll 27b, heated on its bottom and brought together with body 1 carrying the profile rods 5 in calender 28 so that the two bodies 1, 2 are joined, with possible renewed heat supply and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like, with one-sided formation of ribs 3 stiffened by profile rods 5, preferably undetachably, into a two-layered, rubber-elastic body strip 8a provided with ribs 3 of defined size and arrangement, which is wound into a roll 7 for storage purposes. The calender 28 is formed from a sizing roll 28a and at least one nip roll 28b and the sizing roll 28a is provided on its periphery with the recesses 34 corresponding to the ribs 3 to be formed. An adjustment device (not shown) is allocated to at least one roll 28a, 28b to set the gap width between the two rolls, through which any required pressure can also be established.
FIG. 11 shows a section of a body strip 8b consisting of layers A, B and C, to which support slats 3a of defined size and shape are attached at defined spacing on the top of layer A. Attachment of the support slats 3a can occur as follows:
f) The bottom of support slats 3a is laminated with a preferably thin coating 24a using heat and pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like, incorporated and, as required, attached to the endless, rubber-elastic body strip, if necessary with renewed heat supply and/or pressure, optionally with coemployment of an adhesion promoter, vulcanization accelerator, an activator or the like.
g) A comparatively thin coating 24a is laminated onto the top of layer A using heat and/or pressure, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like over the entire surface, partially, in the fashion of a herringbone pattern, a diamond pattern or the like and the support slats 3a are mounted at defined spacing on this coating 24a and joined, especially undetachably, to layer A under pressure, as well as possibly renewed heat supply, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like.
In both cases the layer C can be replaced by the relatively thin coating 24a. As shown in FIG. 13, a device for producing this multilayered body strip 8b according to the invention can also consist of a calender 28 with the two pressure rolls 28a and 28b, to which layers A and B are supplied from supply rolls 27a and 27b. The layers A, B are heated on the bottom or top by appropriate heat sources, for example, hot air. A strip-like or tire-like coating 25a is withdrawn from supply roll 27c, optionally heated on its top and/or bottom by appropriate heat sources, for example, hot air, and also supplied to calender 28 so that the coating 24a is arranged between layers A and B and joined to it under pressure, optionally with renewed heat supply, if necessary with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like, preferably undetachably, into a two- or multilayered body strip 8b.
To implement the idea of the invention according to FIG. 11 and g) a relatively thin additional coating 24a (dashed line) can be unwound from supply roll 27d and fed to calender 28 during heating of its bottom so that it is laminated onto layer A under pressure in the calender, optionally with coemployment of an adhesion promoter, a vulcanization accelerator, an activator or the like, if necessary with renewed heat supply.
Additional embodiments of the invention can be gleaned from the patent claims. | The present invention discloses a glide tube ring for tube-in-tube systems, pipe conduits and the like. The glide ring tube according to the invention is provided with axially spaced glides running parallel to each other whose material has the lowest possible friction coefficient, especially a plastic, preferably a fiberglass-reinforced polyethylene, polyamide or the like, in which the glide tube ring is attached to the central tube forming a closed ring that centers this tube in the protecting tube, pipe conduit or the like. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a novel and useful apparatus for forming a pattern utilizing a line.
Looms have been employed since ancient times to interlace threads or yarns to form a cloth. The offshoot of the looming art is the craft of macrame where a coarse lace or fringe is constructed by knotting threads or chords in geometrical patterns.
U.S. Pat. Nos. 2,218,994, 2,244,085, and 4,046,171 describe looms which may be employed to form articles that are generally woven in odd configuration.
U.S. Pat. No. 4,001,941 shows an apparatus utilized to form a grid portion in order to reproduce graphic arts.
U.S. Pat. Nos. 2,795,031 and 4,045,061 show frames that are used to knot or lace articles.
An apparatus which is capable of forming a pattern of great variation would be a notable advance in the arts and crafts field.
SUMMARY OF THE INVENTION
In accordance with the present invention a novel and useful apparatus for forming a pattern utilizing a line is herein provided.
The apparatus of the present invention includes a frame member having at least a first portion and a second portion spaced from one another. The frame may include a great number of additional portions dependant on the type of pattern to be formed by the apparatus of the present invention. Each portion of the frame member may be straight, curved, or angulated, as the case may be. The frame member may be constructed in a permanent configuration or be formed of components parts that may be assembled in a variety of shapes. Thus, the frame member may be formed with a third portion, or more portions, spaced from the first and second portions and connected thereto, in most cases. For example, the frame member may take the form of a cube, pyramid, a hexagonal solid, and the like. Generally, the first, second, and third portions of the frame member are elongated.
First and second collar elements are also included in the present invention and are rotatably attached to the first and second portions, respectively, of the frame member. Each collar element includes a flexible base portion which at least partially surrounds the particular portion of the frame member. The base of the collar element is separable and removable from the portion of the frame member, the purpose of which will be described hereinafter. Each collar element terminates in a plurality of flexible fingers which are capable of holding a line, preferably by looping the line around each of the fingers.
In the case of the frame member including a corner at the juncture of the first and second portions, the present invention also provides for a removable or replaceable clip which is capable of releasably holding the line. The releasable clip may include a pair of legs which are resiliently linked to one another through a curved or bent portion. The frame member would include at least one recess for engaging the pair of legs to hold the same in place when the line is looped through the corner clip.
The collar element, being rotatably attached to each portion of the frame member, may be rotated to release tension on the line looped through the same. Prior to such rotation, the line is led between frame portions and fingers extending from the respective collar portions may be stiffened by the application of starch, lacquer, or other chemical compound. As heretofore described, rotation of each collar member releases the tension on the line. Subsequent separation of the fingers from the base portion of the collar element completely releases the line from the collar element leaving a free standing pattern or object.
It may be apparent that a novel and useful apparatus for forming a pattern utilizing a line has been described.
It is therefore an object of the present invention to provide an apparatus for forming a pattern utilizing a line which may be employed to form a large variety of patterns quickly and easily.
Another object of the present invention is to provide an apparatus for forming a pattern utilizing a line which may be employed to form a pattern and be quickly and easily released following solidification of the pattern for further use at a later time.
Yet another object of the present invention is to provide an apparatus for forming a pattern utilizing a line which may be assembled into a variety of shapes and, thus, produce a pattern of a predetermined shape and size.
Another object of the present invention is to provide an apparatus for forming a pattern which may be used by students of the arts at an early age.
The invention possesses other objects and advantages especially as concerns particular characteristics and features thereof which will become apparent as the specification continues.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of an embodiment of the frame member of the present invention.
FIG. 2 is a top plan view of another frame member embodiment of the present invention.
FIG. 3 is a perspective view of the collar element used in conjunction with the frame of the present invention.
FIG. 4 is a sectional view taken along line 4--4 of FIG. 1.
FIG. 5 is a sectional view similar to FIG. 4, but showing the flexing of a finger of the collar.
FIG. 6 is a sectional view of a corner of the embodiment of the present invention depicted in FIGS. 1 and 2.
FIG. 7 illustrates the frame member of the invention in the form of a cube.
For a better understanding of the invention reference is made to the following detailed description of the preferred embodiments thereof which should be referenced to the prior described drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Various aspects of the present invention will evolve from the following detailed description of the preferred embodiments thereof which should be referenced to the prior described drawings.
The invention as a whole is shown in the drawings by reference character 10. The apparatus 10 includes as one of its elements a frame member 12. Frame member 12 depicted in FIG. 1 includes first portion 14, second portion 16, third portion 18, and the fourth portion 20. Frame portions 14, 16, 18, and 20 are depicted as elongated tubes that are connected in a square shape by elbows 22, 24, 26, and 28. With reference to FIG. 2, it may be observed that frame member 30 is depicted to be in the shape of approximately the same periphery as frame member 12. However, frame member 30 includes tees 32 and 34 which permit the use of curved frame portion 36 therebetween.
Frame members 12 and 30 are formed with collar elements 38, 40, 42, and 44. Exemplar collar element 44, FIG. 3, indicates that collar element 44 is rotatably attached to fourth portion 20 of frame member 12. Exemplar collar element 44 may be easily attached to any of the portions of frame members 12 or 30. With reference to FIG. 3, it may be apparent that exemplar collar element 44 includes a base portion 46 and a plurality of flexible fingers 48, each of which is capable of extending from base portion 46 and overlapping it by being positioned completely around said base portion 46. With reference to FIG. 4, it may be seen that flexible finger 50 has been closed around frame portion 20 to hold collar element 44 to the same. In addition, flexible finger 50 fits around frame portion 20 loosely enough to permit line 52 to lie between flexible finger 50 and frame portion 20. Referring to FIG. 5, it may be seen that collar element 44 has been rotated about frame portion 20 such that line 52 is capable of leaving the confines between flexible finger 50 and frame portion 20 as desired.
Referring back to FIG. 1, it may be observed that line 50 has been laced between frame members 16 and 20 and is held thereto by collar elements 40 and 44, respectively. In addition, a line 54 has been run between frame elements 14 and 18 and held thereto by collar elements 38 and 42, respectively. Referring to FIG. 2, in particular, collar element 39 has been employed with curved frame portion 36 to permit a line 56 to run between frame portion 36 and frame portion 14 of frame member 30.
FIGS. 1 and 2 also depict corners formed by elbows 22, 24, 26, and 28 of frame members 12 and 30. Releasable clips 58 are employed with respect to frame members 12 and 30 to permit lines, such as line 56 on FIG. 2, to be held at this juncture. Referring to FIG. 6, it may be observed that clip 60 is illustrated at elbow 26, FIG. 1. Elbow 26 is provided with a recess 62 such that releasable clip 60 may fit therein. Releasable clip 60 is formed with legs 64 and 66 which are springy relative to bent portion 68 thereof. Protuberances 70 and 72 on legs 64 and 66, respectively, prevent clip 60 from pulling from recess 62 under the tension of a line. Referring to FIG. 1, line 74 is depicted between releasable clip 60 and releasable clip 76 at elbows 26 and 22, respectively.
Although apparatuses 10 and 30 have been shown in FIGS. 1 and 2 as possessing essentially only two essential dimensions, FIG. 7 illustrates frame member 76 in the form of a cube. Other solid geometric shapes, straight or curved, may be formed in the present apparatus 10 since the frame portions and connectors such as elbows 22, 24, 26, and 28 may be removably attached to one another. FIG. 7 depicts a plurality of riser tees 78 forming the corners of the cube of frame member 76.
In operation, the user obtains or forms frame member 12, 30, or 76, or another shape as desired. Plurality of collar elements such as collars 38, 40, 42, and 44 with respect to frames 12 and 30 are attached to the frame portions as depicted in FIGS. 1 and 2 by opening the plurality of flexible fingers 48 and passing the same over the particular side portion of frame member 12 or 30. Line such as lines 51, 52, 54, 56, or 74 may be passed between any of the fingers of plurality of fingers 48 of any of the collar elements depicted therein by stretching the same relative to base portion 46. Thus, pattern 80, FIG. 1, is formed with respect to frame member 12, pattern 82, FIG. 2, is formed employing frame member 30, and another pattern 84 is formed with respect to frame 76, FIG. 7. Patterns 80, 82, and 84 may be stiffened or made rigid by the use starch, lacquer, or other chemical which may be sprayed on the lines found in frames 12, 30, or 76. Following such stiffening process, each of the collar element such as collar element 44, may be rotated about any of the frame portions such as frame portion 20, to permit the easy release of the lines held thereby. Plurality of releasable clips 58 may be removed from any of the corners of frame members 12, 30, or 76 by squeezing each of the springy legs, such as springy legs 64 and 66 with respect to clip 60, together and permit the removal from exemplar recess 62 with respect to elbow 26. Thus, each of the frames 12, 30, and 76 are reusable or may be assembled into different shapes for reuse.
While in the foregoing, embodiments of the present invention have been set forth in considerable detail for the purposes of making a complete disclosure of the invention, it may be apparent to those of skill in the art that numerous changes may be made in such details without departing from the spirit and principles of the invention. | An apparatus for forming a pattern utilizing a line which interacts with a frame member. The frame member includes at least a first portion and a second portion spaced from each other. First and second collar elements are rotatably attached to the first and second portions of the frame member. Each of the first and second collar elements possess a plurality of flexible fingers, each finger being capable of releasably holding the line. The frame members may be straight, angulated, or curved as desired. | 3 |
FIELD OF THE INVENTION
The present invention relates to a fire prevention automation commanding control system using satellite-location/geography-information, and in particular to a fire prevention automation commanding control system uses a central processing computer to integrate radio transmission, satellite location, geography information, facility control, image monitoring, underground piping control, piping monitoring, mobile/stationary communication, and a fire detection alarm device into an integrated fire prevention system performing automatic command, control, communication, information processing, i.e., so-called C31 system.
BACKGROUND OF THE PRESENT INVENTION
At present, there are increasing counts of fire caused by gas (nature gas, liquid petroleum, and the like) explosion, improper use of electrical equipment, or arson, and it frequently results in tremendous loss of life and property simply due to usually delayed report to the police. With today's high tech development, things get even worse because people often neglect disaster prevention measure due to their busy life. However, there is no such system available in the market that provides a well-facilitated fire prevention command/control system performing simultaneous fire evidence searching, prevention, and self-alarming. Therefore, it is necessary to utilize a central processing unit (CPU) and software programming to develop a system integrating radio transmission principle, satellite location technology, and systems such as geography information, facility control, image monitoring, underground piping control, piping monitoring, mobile/stationary communication and a common detection alarm, which is capable of automatic commanding, controlling, communication, and information processing. With such system, it is possible to effectively avoid or greatly reduced above disasters.
SUMMARY OF THE INVENTION
Therefore, it is an object of present invention is to provide a fire prevention automation commanding control system using satellite-location/geography-information, which uses a central processing computer to integrate radio transmission, satellite location, geography information, facility control, image monitoring, underground piping control, piping monitoring, mobile/stationary communication, and a fire detection alarm device into an integrated fire prevention system performing automatic command, control, communication, and information processing. With such system, it is possible to make a rapid detection of fire and suppress the occurrence or expansion of fire in time as well as perform first time evidence searching and effectively command/control rescue operation.
To achieve above object, a fire prevention automation commanding control system using satellite-location/geography-information is provided, including:
a indoor safety automatic detection/cut-off system having:
a plurality of radio signal detectors/transmitters, which detect gas, flame, smoke, and carbon monoxide respectively, and automatically generate detection signals and transmit radio signals;
a plurality of radio-signal camera/receiver, which receive radio-signals transmitted by at least one of said plurality of radio-signal detectors/transmitters and activate a radio-signal camera/receiver corresponding to said at least one of the radio-signal detectors/transmitters;
a central controller, which receives a detection signal generated by said at least one of the radio-signal detectors/transmitters and generates a control signal; and
a gas self cut-off device, which automatically cut-off the supply of gas according to said control signal generated by said central controller;
a subscriber-end system automatic communication device having:
a power supply, which supplies electricity;
a radio-signal receiver, which receives radio-signals transmitted by at least one of said plurality of radio-signal detectors/transmitters;
an input/output device, which is connected to said radio-signal receiver so as to input/output said radio-signals;
a central processing unit, which is connected to said input/output device so as to process said radio-signals and generate data;
a random access memory, which provides information required by said central process unit and store data generated by said central process unit;
a multi-frequency auto-dial telephone/circuit, which automatically dial according to said input/output device by means of signals and data provided by said central process unit and said random access memory;
an image compression/control device, which controls and compresses image signals outputted by said camera and transfers them to said multi-frequency auto-dial telephone/circuit;
a device for fire-department operation command center having:
an image decompression and video recording device, which decompresses image signals inputted from above output of camera;
a central processing unit, which processes data and image signals outputted by said multi-frequency auto-dial telephone/circuit and generates a telephone-confirm signal as well as the analytic data of the whole system;
a subscriber management device, which manages and stores data associated with subscribers;
an electronic map device of geography information, which provides geography information required by associate electronic map;
a database, which stores data of underground piping including gas and electricity;
an underground piping self-monitoring device, which controls cut-off operation of said underground piping; and
a communication system interface processing device, which is coupled via a RS-232 interface to said central process unit as well as a VHF/UHF radio control device, a satellite receiving device, a satellite communication device, data mobile communication device, and a satellite location vehicle commanding device.
Furthermore, in the fire prevention automation commanding control system using satellite-location/geography-information according to present invention, said communication system interface processing device is also coupled to a device for ambulance, a device for fire engine, a device for patrolling vehicle, a device for piping unit rescue vehicle, and a device for mobile commanding vehicle, wherein:
said device for ambulance has a satellite location navigation command/control device, a mobile communication device, and a medical affairs control device;
said device for fire engine has a satellite-location navigation command/control device, a mobile communication device, and a fire prevention operation command/control device;
said device for patrolling vehicle has a satellite location navigation command/control device, a mobile communication device, and a police operation command/control device;
said device for piping unit rescue vehicle has a satellite location navigation command/control device, a mobile communication device, and a geography information piping management device;
said device for mobile commanding vehicle has a satellite location navigation command/control device, a mobile communication device, a police command/control device, and a geography information inquiring device.
BRIEF DESCRIPTION OF DRAWINGS
The above and other objects, features, and advantages of present invention will become more apparent from the detailed description in conjunction with the following drawings, in which:
FIG. 1 is a block diagram schematically showing fire prevention automation commanding control system using satellite-location/geography-information in accordance with present invention; and
FIG. 2 exemplifies a device for vehicle arranged in accordance with present invention;
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, a fire prevention automation commanding control system using satellite-location/geography-information according to present invention is equipped with a indoor safety automatic detection/cut-off system 1 , a subscriber-end system automatic communication device 2 , and a device for fire-department operation command center 3 . Said indoor safety automatic detection/cut-off system 1 comprises: a plurality of radio signal detectors/transmitters 11 , which detect gas at 11 a , flame at 11 b , smoke at 11 c , and carbon monoxide at 11 d respectively, and automatically generate detection signals for a central controller 13 and transmit radio signals; a plurality of radio-signal camera/receiver 12 , which receive radio-signals transmitted by at least one of said plurality of radio-signal detectors/transmitters 11 ( 11 a , 11 b , 11 c , and 11 d ) and activate a radio-signal camera/receiver 12 corresponding to said at least one of the radio-signal detectors/transmitters 11 ; a central controller 13 , which receives a detection signal generated by said at least one of the radio-signal detectors/transmitters and generates a control signal; and a gas self cut-off device, which automatically cut-off the supply of gas according to said control signal generated by said central controller. Said subscriber-end system automatic communication device 2 comprises: a power supply 21 , which supplies electricity; a radio-signal receiver 22 , which receives radio-signals transmitted by at least one of said plurality of radio-signal detectors/transmitters 11 ; an input/output device 23 , which is connected to said radio-signal receiver 22 so as to input/output said radio-signals to/from a central processing unit 24 ; a central processing unit 24 , which is connected to said input/output device 23 so as to process said radio-signals and generate data; a random access memory 25 , which provides information required by said central process unit 24 and store data generated by said central process unit 24 ; a multi-frequency auto-dial telephone/circuit ( 26 a , 26 b ) which automatically dials according to said input/output device 23 by means of signals and data provided by said central process unit 24 and said random access memory 25 ; an image compression/control device ( 27 a , 27 b ), which controls and compresses image signals outputted by said camera 12 and transfers them through said multi-frequency auto-dial telephone/circuit ( 26 a , 26 b ) to a device for fire-department operation command center 3 .
Said device for fire-department operation command center 3 comprises: an image decompression and recording device 33 , which is connected to multi-frequency auto-dial circuit ( 31 , 32 ) and decompresses image and video signals inputted from above output of camera; a central processing unit 34 , which processes data and image signals outputted by said multi-frequency auto-dial telephone/circuit ( 26 a , 26 b , 31 , 32 ) and generates a telephone-confirm signal as well as the analytic data, said telephone-confirm signal is then transferred to said multi-frequency auto-dial telephone/circuit 26 a of said subscriber-end system automatic communication device 2 , while said analytic data is transferred to a integration interface 36 and a underground piping self-monitoring device 41 through a operation system 35 of said central processing unit 34 , respectively; a subscriber management device 37 , which is connected to said integration interface 36 and provide data associated with subscribers such as address and piping arrangement to said central processing unit 34 and a system integration interface 40 in accordance with said analytic data of said central processing unit 34 ; a electronic map device of geography information 38 , which is connected to said integration interface 36 and provides an electronic map representing geography spatial information to said central processing unit 34 and a system integration interface 40 in accordance with said analytic data of said central processing unit 34 ; a database 39 , which is connected to said integration interface and provides underground piping arrangement data such as underground petroleum, gas, electricity, water resource to said central processing unit 34 and a system integration interface 40 in accordance with necessity generated according to said analytic data of said central processing unit 34 and geography information of said electronic map device 38 ; an underground piping self-monitoring device 41 , which controls cut-off operation of underground piping such as underground petroleum, gas, electricity in accordance with said analytic data of said central processing unit 34 and said underground piping arrangement of said database; and a communication system interface processing device 43 , which is coupled via a RS-232 interface 42 to said central process unit 34 as well as a VHF/UHF radio control device 44 , a satellite receiving device 45 , a satellite communication device 46 , data mobile communication device 47 , and a satellite location vehicle commanding device 48 . Said communication system interface processing device 43 can also be coupled to devices for vehicle such as ambulance 51 , fire engine 52 , patrol vehicle (include traffic control vehicles) 53 , piping unit rescue vehicle 54 , and mobile commanding vehicle 55 . Said device for ambulance has a satellite-location navigation command/control device 511 , a mobile communication device 512 , and a medical affairs control device 513 ; said device for fire engine 52 has a satellite location navigation command/control device 521 , a mobile communication device 522 , and a fire prevention operation command/control device 523 ; said device for patrolling vehicle 53 has a satellite location navigation command/control device 531 , a mobile communication device 532 , and a police operation command/control device 533 ; said device for piping unit rescue vehicle 54 has a satellite location navigation command/control device 541 , a mobile communication device 542 , and a geography information piping management device 543 ; said device for mobile commanding vehicle 55 has a satellite location navigation command/control device 551 , a mobile communication device 652 , a police command/control device 553 , and a geography information inquiring device 554 .
As described above, said indoor safety automatic detection/cut-off system 1 according to present invention is a major portion of prevention and alarming in the system. Detectors ( 11 a , 11 b , 11 c , 11 d ) use here must pass the standard inspection of associate regulation, should there be any leakage of gas or in case of fire detected and the alarm be activated, the system will immediately cut-off the supply of gas. It is very likely that people are in panic, thought someone else has already report to the police, or cannot remember relevant phone numbers, or too busy on getting out to report the event, determined to commit suicide, so that by the time passerby did report to the police and the fire fighters had arrived the scene it will be too late for first time rescue. Therefore, the present invention has incorporated a device for MDTF (multi-frequency auto-dial telephone) and developed said subscriber-end system automatic communication device 2 such that whenever detectors ( 11 a , 11 b , 11 c , 11 d ) have been activated, it will then automatically send a message to said device for fire-department operation command center 3 . Furthermore, the present invention has also designed a self-confirm telephone and a mistake prevention design to avoid faulty report of a fire.
In addition, said device for fire-department operation command center 3 is the core of the system, whose functions includes:
(1) When a disaster alarm signal is transferred in through a public communication line, said device 3 will automatically detects the identification code and immediately retrieve and display the subscriber's fundamental data such as name, phone number, and address.
(2) The policemen on duty need only push a button and said device 3 will automatically call back said system of a preset phone number to confirm the actual situation.
(3) At the time the policeman on duty pushed the button, said device 3 will automatically incorporate with geography information system 38 to show an electronic map of target area.
(4) By means of said geography information system 38 , it is possible for the system to show information associated with subscribers such as neighboring fire hydrant (water resource), nearby hospital, unit and quantity of ambulance, best way to access, traffic control routing, road block position, option of mobile commanding site position, and condition of underground piping, etc.
(5) After the disaster is confirmed, said device will rapidly command fire, engine 52 , ambulance 51 , and backup force 53 to the scene through a police operation communication device.
(6) Mobil vehicle such as fire engine 52 , ambulance 51 , and backup force 53 may rapidly get to the scene by making use of satellite-location self-navigation device.
(7) Backup force and fire engine from outside district can also get to the scene and find water resource through said satellite-location self-navigation device.
(8) Said operation command/control center 3 can use a satellite-location commanding system to know the position of all vehicles involving the rescue and directly command the operation.
(9) People in the utility facilities such as gas company, electricity company, petroleum company, and telecommunication company may corporate to reduce the damage to a minimum scale.
(10) Said system has stored data associated with all residencies and regulated business within the district or community.
(11) Said satellite-location navigation command/control device used in present system can handle at least 2000 specific target simultaneously.
It is understood that present invention is not limited to above description and is allowed to have various modification and change, however, the spirit and scope of present invention is considered to fall within claims as following.
LIST OF REFERENCE NUMERALS
1 indoor safety automatic detection/cut-off system
11 a gas detector/raid signal transmitter
11 b flame detector/radio signal transmitter
11 c smoke detector/radio signal transmitter
11 d carbon monoxide detector/radio signal transmitter
12 digital camera+radio receiver
13 central controller
14 gas auto-cut-off value device
2 subscriber-end system automatic communication device
21 power supply
22 radio signal receiver
23 input/output device
24 CPU
25 RAM
26 a multi-frequency automatic telephone
26 b auto-dial crime reporting circuit
27 a image compressing device
27 b image control device
3 fire-department operation command center
31 multi-frequency auto-dial circuit Tx
32 multi-frequency auto-dial circuit Rx
33 image decompression & recording device
34 control processing computer
35 operation system
36 system integration interface
37 subscriber management device
38 geographic information device/electronic map
39 data base
40 system integration interface
41 underground piping self-monitoring system
42 RS-232 interface
43 communication interface processing device
44 V/UHF radio control device
45 satellite receiving device
46 satellite communication device
47 data mobile communication device
48 satellite locating vehicle commanding device
51 device for ambulance
511 satellite location navigation command/control device
512 mobile communication device
513 medical affairs control device
52 device for fire engine
521 satellite location navigation command/control device
522 mobile communication device
523 fire prevention operation command/control device
53 device for patrolling vehicle
531 satellite location navigation command/control device
532 mobile communication device
533 police operation command/control device
54 device for piping unit rescue vehicle
541 satellite location navigation command/control device
542 mobile communication device
543 geography information piping management device
55 device for mobile commanding vehicle
551 satellite location navigation command/control device
552 mobile communication device
553 police command/control device
554 geography information inquiring device | The prevent invention provides a fire prevention automation commanding control system using satellite-location/geography-information, which uses a central processing computer to integrate radio transmission, satellite location, geography information, facility control, image monitoring, underground piping control, piping monitoring, mobile/stationary communication, and a fire detection alarm device into an integrated fire prevention system performing automatic command, control, communication, information processing and on-site evidence collection, i.e., so-called C31 system, so that it is possible to rapidly detect fire and effectively command and control the rescue operation. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a novel woven cloth and more particularly to a cloth used in the fabrication of sails.
Modern sail technology requires the use of cloths of synthetic materials having various weaves, weights, and finishes. The cloth used in a spinnaker, for example, must be light in weight, resistant to tear, and have low porosity. Another important factor is stretch resistance, which allows a predictable shape to be maintained in the sail under various wind conditions.
Most sail cloths are made by weaving polymeric yarns in a conventional manner. The woven cloth is usually heat treated and coated with a resin. The cloth may also be laminated to a continuous film to improve stretch resistance. In the production of spinnaker cloth, very fine yarns of polyamid fibers are woven together. Due to the fineness of the yarns and the the weaving process requires a relatively long time per unit area of cloth.
SUMMARY OF THE INVENTION
In accordance with the present invention, in a sail cloth having warp and weft yarns, either the warp or the weft is replaced by tapes composed of a film of polymeric material. Since the tapes are substantially wider than the yarns, fewer weaves are required to make the cloth. Also, porosity is greatly reduced because of the relatively large surface area of the tapes in comparison with conventional yarns. Moreover, the stretch in the direction of the yarns is considerably reduced because the tapes bend the yarns less than would be the case in conventional cloth.
THE DRAWING
The sole FIGURE is a perspective view of the novel cloth of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the drawing, the cloth of the present invention comprises a plurality of individual spaced yarns 10a, b, c and d, which are woven with a plurality of spaced tapes 12a, b, c, with the respective yarns and tapes intersecting at right angles. Conventional weaving methods may be used to make the cloth, and the tapes 12 may replace either the weft or warp yarns.
In accordance with the conventional weaving process, the warp yarns or tapes are stretched horizontally side by side on a loom, with alternate yarns being separated by a system of frames. During each weave, the frames pull the alternate warps vertically apart. Through this space is passed a shuttle carrying the weft yarn or tape, which shoots back and forth at high speed. The weft is held straight under tension while the warp-holding frames change position, causing the warps to be wrapped or crimped over and under the wefts.
It may be seen that the width of each tape 12 is substantially wider, at least 4 times and preferably more than 10 times wider than the yarn 10. Although the tapes are shown as being of equal width, various combinations of widths may be employed. The thickness of the tapes may range in the order of from about 0.00025 to 10 mil, whereas the denier of the yarns may be selected from all those suitable for the desired properties in the final product.
The tapes 12 may be prepared from a roll of polymeric film material. Suitable polymers include polyester, polyamid, acrylic, and polyolefins. The yarns 10 are made of conventional fibers which preferably include materials such as polyester, aramid, polyamid, carbon and the like.
Upon production of the cloth as shown, it may be subjected to conventional secondary treatments, such as coating with a curable resin, heat treating, calendering and the like. Also, the cloth may be laminated to a separate sheet of continuous polymer film, such as polyester film.
It may be seen that since a single tape 12 replaces a number of conventional yarns, fewer weaves and hence less loom time are required to produce the cloth in comparison with conventional cloth. The cloth is also relatively non-porous and is highly stretch resistant in the direction of the yarns 10. Variations in the width and thickness of the tapes, as well as the denier and spacing of the yarns may be employed to attain the optimum properties required for a particular application.
In the construction of a sail, a plurality of panels are prepared from the improved cloth of the present invention. Adjacent panels may then be joined in the conventional fashion, such as by stitching or bonding. The orientation of the cloth in the sail will be dependent upon the properties desired. For example, the cloth may be oriented such that the yarns 10 are substantially aligned in the direction of maximum load in the sail. | Sail cloth is made up from a plurality of yarns in one direction woven together with a plurality of film tapes in the other direction to provide a cloth having improved properties. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to an apparatus for feeding a fiber tuft mass (fiber batt), composed of, for example, cotton fibers, synthetic fibers or the like, to a fiber processing machine, such as a carding machine or a cleaner to prepare the fiber for spinning. The apparatus has a fiber advancing mechanism formed of a feed roll and a cooperating feed table followed by at least one opening device such as an opening roll. The fiber advancing mechanism also serves as a batt thickness sensor. For this purpose the feed table is formed of a plurality of individually movable feed table segments which undergo excursions as the throughgoing fiber batt changes in thickness. Each movable feed table segment is biased towards the feed roll by a spring arrangement and is connected, with the intermediary of the respective springs, with a rotatably supported biased common holding element which senses the sum of the displacements of the individual feed table segments.
In a known apparatus of the above-outlined type, generally referred to as pedal-type or piano key-type regulating device, a fiber batt feeding aggregate and a rapidly rotating opening roll are arranged in series. The batt feeding aggregate is formed of a feed roll with feed table and upstream thereof (as viewed in the direction of fiber feed) there is arranged a sensor device having a fiber batt advancing roll cooperating with a plurality of sensor fingers. Thus, the sensing and feeding of the fiber material to the opening roll are spatially separated. By means of the sensor fingers the sensor device mechanically detects thickness variations of the fiber batt at several locations along the width of the fiber batt. Each sensor finger is an angled, two-arm lever rotatably held in its mid portion. The free end zone of one lever arm forms the sensor member proper, while at the free end zone of the other lever arm a tension spring is attached. In this manner each sensor finger is movably mounted for displacement in response to thickness variations in the fiber batt and each sensor finger is individually biased by its tension spring in such a manner that the sensor fingers press the fiber material against the feed roll. All tension springs are attached with one of their ends to one lever arm of a rotatably supported common two-arm summing lever. The other arm of the summing lever is attached to a weight, whereby to each sensor finger a fiber material pressing force is imparted with the intermediary of the tension springs and the summing lever. With the other lever arm of the summing lever an inductive proximity switch is associated which transforms excursions into electric pulses. A delayed, path-dependent shift register ensures that the corresponding regulating pulse affects the rotary speed of the downstream connected feed roll of the feed roll/feed table assembly (feeding assembly) for the opening roll only when the respective sensed areas of the fiber batt arrive in the working zone of the fiber feeding assembly.
It is a disadvantage of the above-outlined prior art construction that it is structurally complex and it is complicated to assemble. A great number of individual structural elements are required, for example, a separate rotary bearing has to be provided in order to support individually each sensor finger. Such rotary bearings are complex, expensive and they must be aligned with high precision. It is a further disadvantage of the prior art arrangement that the sensor fingers are separately connected with the common summing lever. Thus, the tension springs are needed as separate force-transmitting elements between the lever arms of the sensor fingers and the spaced lever arm of the summing lever. The individual tension springs are attached (hooked) at their ends with a certain clearance and their elongation may lead to tolerances and deviations which jeopardizes accurate measurements during operation. Particularly the determination of the sum of the thickness deviations is imprecise because the excursion of each individual sensor finger is measured indirectly. Because of the possibility of deviations in the tension springs, a uniform clamping of the fiber material along its width is adversely affected as well.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved apparatus of the above-outlined type from which the earlier discussed disadvantages are eliminated, which is particularly structurally simple and makes possible an improved measurement and clamping of the fiber batt.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the apparatus for feeding a fiber batt to a fiber processing machine includes a feed roll; a feed table formed of a plurality of separately movable feed table segments each cooperating with the feed roll and defining therewith a nip through which the fiber batt passes; a plurality of springs each being affixed to the feed table segment to form integral components therewith; and an elongated holding element extending spaced from, and generally parallel to the feed roll. Each spring is affixed to the holding element. The feed table segments are individually movable away from the feed roll against a force of respective springs in response to thickness variations in the fiber batt as the fiber batt passes through the nip. There is further provided a support for rotatably supporting the holding element. The feed table segments impart torques on the holding element through the respective springs as a function of movements of the feed table segments and the holding element is rotated by the torques to an extent representing a sum of the torques. A sensor is connected to the holding element for generating a signal as a function of rotary displacements of the holding element.
The invention provides an apparatus which is structurally simple and is uncomplicated to install and further makes possible an improved measurement (thickness sensing) and clamping of the fiber material. By the plurality of feed table segments an individual (zonewise separated) measuring and clamping of the fiber material along the entire width of the fiber batt is possible. Further, the mechanical summing is structurally simple; only a single sensor is required. It is a particular advantage of the invention that each feed table segment and the associated spring constitute an integral structural component. The spring has several functions: it firmly holds the feed table segment (securement of the segment), it holds the segment in position relative to the feed roll, and, being itself secured to the holding element, it also secures the segment to the holding element. Furthermore, as the segment undergoes an excursion in response to a thickness variation of the throughgoing fiber batt, it imparts a torque to the holding element, that is, it transfers the excursion of the segment directly to the holding element as a rotary motion. By virtue of the measures according to the invention, particularly by virtue of the integral construction of each segment and its spring on the one hand and the springs and the holding element, on the other hand, all excursions of the feed trays are transferred through a short path to the holding element simply, directly and immediately to thus sense the sum of the displacements. The apparatus is simple, because individual rotary bearings for the individual feed table segments are no longer needed. Furthermore, the apparatus is easy to install since there is no need to secure each individual segment via a spring but the entire apparatus may be installed as a single structural component.
The invention has the following additional advantageous features:
The spring is a leaf spring and with each feed table segment there is associated at least one leaf spring and is connected therewith by screws, rivets or an adhesive. By using leaf springs, the connection is particularly simple and permanent since relatively large surfaces are available for securement.
With each feed table segment there are connected two leaf springs which, as viewed in the direction of fiber feed, are attached at the upstream and downstream ends of the segments.
Each leaf spring is, at one end, firmly secured to the feed table segment and is, at the other end, firmly secured to the holding element.
The leaf springs for each feed table segment are spaced from one another in the direction of fiber feed.
The leaf springs are arranged parallel to one another.
The leaf springs are relatively stiff in the direction viewed parallel to the distance between feed table segment and holding element and are relatively soft in the direction viewed perpendicularly to a plane defined by such distance and the axis of the feed roll.
The holding element is a longitudinal beam oriented axially parallel to the feed roll.
The holding element is torsion resistant.
An axially extending torsion bar is attached to an end of the holding element. The torsion bar is biased by a spring or is itself a torsion spring.
The torsion bar is supported with a soft resilient force.
The torsion bar is supported in a stationary bearing.
The bias of the torsion bar is adjustable.
The holding element is, at one end, supported in a rotary bearing.
The torsion bar is associated with a measuring element for measuring the extent of the rotary displacement of the holding element.
The measuring element is an inductive path sensor.
The measuring element includes expansion measuring strips.
The feed table segments arranged along the length of the feed roll mechanically detect thickness variations of the fiber batt at various locations along the fiber batt width and the variations are, by means of the common holding element, combined into an average value of thickness variations.
Dependent upon the deviation of an actual average value from a desired value, the fiber quantities (supply rate) to the fiber processing machine are varied.
The fiber feeding apparatus is, as a measuring and clamping device, arranged directly upstream of the opening roll. In this manner the feed table fulfills not only its usual role as a clamping device but has a dual function because it simultaneously serves as a measuring member so that additional devices for measuring the thickness fluctuations in the inlet zone of the fiber processing machine may be omitted.
The feed table segments are arranged above the feed roll.
The leaf springs project in the securing zone of the feed table segments into the nip between the slowly rotating feed roll and the rapidly rotating opening roll.
With the feed table segments there is associated a fixed abutment element which has a dual function: it prevents the feed table segments from contacting the feed roll and provides for a bias for-the leaf springs.
The feed roll support is fixed.
The distance between the surfaces of the feed table segments and the circumferential surface of the feed roll decreases along the roll circumference viewed in the working direction.
The distance between the feed table segments on the one hand and the circumferential surface of the feed roll on the other hand is the smallest at the clamping location (nip).
The feed table segments are hollow extruded components. The cavity of the segments is coupled to a vacuum or air pressure source.
In the clearance between two adjoining feed table segments a seal is arranged.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic side elevational view of a carding machine incorporating the invention.
FIG. 2 is a perspective view of a preferred embodiment of the invention.
FIGS. 3 and 4 are schematic sectional side elevational views of two further preferred embodiments of the invention.
FIGS. 5, 6 and 7 are schematic perspective views of three further preferred embodiments of the invention.
FIGS. 8 and 9 are sectional side elevational views of two further preferred embodiments of the invention.
FIG. 10 is a schematic side elevational view of a further preferred embodiment of the invention illustrating the feed table segments underneath the feed roll.
FIG. 11 is a sectional side elevational view of a pneumatic fiber tuft feeder incorporating the invention.
FIG. 12 is a sectional side elevational view of a further preferred embodiment of the invention.
FIGS. 13, 14, 15a, 15b, 16, 17, 18a, 18b, 19a, 19b and 19d are schematic perspective views of eleven further preferred embodiments of the invention.
FIG. 19c is a schematic side elevational view of yet another preferred embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning to FIG. 1, there is illustrated therein a carding machine which may be, for example, an EXACTACARD DK 760 model, manufactured by Trutzschler GmbH & Co. KG, Monchengladbach, Germany. The carding machine has a feed roll 1, a feed table 2, a licker-in 3, a main carding cylinder 4, a doffer 5, a stripping roll 6, crushing rolls 7 and 8, a web guiding element 9, a sliver trumpet 10, calender rolls 11 and 12 as well as travelling flats 13.
Turning to FIG. 2, above the feed roll 1 there are serially arranged feed table segments 2a, each being connected with a holding element 15--functioning as a summing beam--by means of an associated front leaf spring 14a and a rear leaf spring 14b. The holding element 15, whose length dimension is oriented parallel to the rotary axis 1' of the feed roll 1, is provided at one end with a torsion bar 18 fixedly held in a stationary support 16. From the opposite end of the holding element 15 a shaft 35 extends which is movably supported in a bearing 17. Between the feed table segments 2a and the feed roll 1 a fiber batt 19 passes which, in the zone of the clamping location (nip) between feed roll and feed table segment has a thickened part 20, causing the feed table segment 2a to execute an excursion in the direction of the arrow G. By virtue of such an excursion the leaf springs 14a and 14b are moved in the directions of arrows F, F'. Such an excursion leads to a rotary motion of the holding element 15 in the counterclockwise direction as indicated by the arrow D, causing a torsional deformation of the torsion bar 18 in the direction of the arrow A, whereby the expansion measuring strips 23 are deformed and such a deformation may be represented by a signal. After regulation, the torsion effect is cancelled, that is, the torsion bar 18 and the holding element 15 rotate back in the direction of arrows B and C, respectively, the leaf springs 14a, 14b swing back in the direction of the arrows E, E' and the feed table segment 2a moves in the direction H into its initial position
In the embodiment illustrated in FIG. 3, the holding element, that is, the summing (adding) beam 15 clampingly holds the springs 14 (only one visible). Each feed table segment 2a (only one visible) has at one end a foot 2a' affixed to the lower end of the respective spring 14.
The embodiment according to FIG. 4 includes a channel 34 which extends from a non-illustrated card feeder and which opens in the fiber grasping zone formed of the feed roll 1 and the feed table segments 2a. The channel 34 has an apertured portion 33 shrouded by suction hoods 32. Similarly to FIG. 3, the feed table segments 2a have a foot 2a' and are connected by respective leaf springs 14 with the holding element 15. In the fiber intake zone a sealing flap 31 extends which at its upper end is secured to the holding element 15.
In the embodiment illustrated in FIG. 5 the fiber batt 19 is advanced on a transfer tray 39 to the feed roll 1 above which the feed table segments 2a are supported by respective springs 14 which extend generally horizontally and are secured to the holding element 15. Underneath the springs 14 a rectangular abutment bar 37 extends parallel to the feed roll 1. The abutment bar 37 prevents the feed bar segments 2a from contacting the feed roll 1. The rear terminus of each leaf spring 14 is secured to the holding element 15 which is rotatably supported by bilaterally extending shafts 35a, 35b which, in turn, are rotatably held in bearing blocks 17a, 17b. At their extensions beyond the bearing blocks 17a, 17b the shafts 35a, 35b carry respective levers 28a, 28b which are biased in the direction of fiber feed by means of respective compression springs 21a, 21b. To each lever 28a, 28b there is connected a plunger armature of respective inductive path sensors 22a, 22b which emit a signal representing the extent of the displacement of the plunger armature.
The embodiment illustrated in FIG. 6 is similar to that shown in FIG. 5 except that instead of shafts 35a, 35b shown in FIG. 5, the holding element 15 is, at each end, provided with torsion bars 18a, 18b which are held in fixed supports 16a, 16b, respectively. The torsion bars 18a, 18b carry expansion measuring strips 23 by means of which the motion, that is, the rotation of the holding element 15 is detected.
In the embodiment illustrated in FIG. 7 the construction which is similar to that of FIG. 5, also has a regulatable biasing device 27 which includes a stationary nut 25 affixed to the machine frame, a threaded spindle 29 threadedly engaging and passing through the nut 25, a pressure plate 26 carried at one end of the spindle 29 and a handwheel 24 attached to the opposite end of the spindle 29. The pressure plate 26 is connected with the loading arm 28 of the shaft 35 by means of a compression spring 30. The desired bias on the holding element 15 is thus adjustable by turning the handwheel 24. It will be understood that instead of the handwheel 24 a motorized adjusting mechanism may be used.
In the embodiment illustrated in FIG. 8 the frontal and rear leaf springs 14a and 14b are of different length and the frontal leaf springs 14a are so designed that they extend into the nip between the feed roll 1 and the licker-in (opening roll) 3. The leaf springs 14a and 14b are attached by screws 38 at their lower ends to the feed table segments 2a and at their upper ends to the holding element 15. The abutment bar 37 is mounted adjacent a projection 42 provided on a rear portion of each feed table segment 2a, and the clearance between the abutment bar 37 and each projection 42 is so designed that even in case of a bias the feed table segments 2a cannot contact the feed roll 1. To ensure that the leaf springs 14a, 14b do not enter into contact with the walls of the holding element 15 and the feed table segments 2a to thus allow an unimpeded motion of the feed table segments, the feed table segments 2a and the holding element 15 are provided with recesses 36 in the zone of the leaf springs 14a, 14b. On the underface of the holding element 15 a support bar 40a is carried whereas on the top face of each feed table segment 2a a support post 40b is arranged. Between each post 40b and the support bar 40a a spiral spring 41 is arranged which, in addition to the leaf springs 14a and 14b resiliently suspends the respective feed table segment 2a from the holding element 15.
In the embodiment illustrated in FIG. 9 the leaf springs 14a and 14b attaching each feed table segment 2a to the holding element 15 are inclined rather than in a perpendicular arrangement with respect to the segments 2a and the holding element 15 as it was the case in the earlier described embodiments. Further, the holding element 15 has along its entire length, that is, in a direction transversely to the advancing direction of the fiber material, an abutment bar 37b affixed to an underside thereof with which cooperate respective abutment posts 37a mounted on the top face of each feed table segment 2a. The distance between the abutment bar 37b on the one hand and the abutment posts 37a on the other hand is less than the width of the smallest clearance between the feed roll 1 and the feed table segments 2a to thus securely prevent any feed table segment 2a from contacting the feed-roll 1.
In the embodiment illustrated in FIG. 10 the feed table segments 2a (only one visible) are arranged underneath the feed roll 1. Here too, the individual feed table segments 2a are connected with the holding element 15 by means of leaf springs 14a, 14b. The holding element 15 is at both ends connected with a torsion bar 18. A regulating device (microcomputer) 50 is provided, an input of which receives signals which represent the displacements of the torsion bar 18 and an output connected to the drive motor 52 of the feed roll 1 to regulate the speed of the feed roll 1 as a function of the thickness variations of the fiber batt 19 as it passes between the feed roll 1 and the feed table segments 2a.
Turning to FIG. 11, there is illustrated a fiber tuft feeder which supplies a carding machine with the fiber batt 19. The fiber tuft feeder may be an EXACTAFEED FBK 533 model, manufactured by Trutzschler GmbH & Co. KG, Monchengladbach, Germany. The fiber material is pneumatically delivered in a fiber tuft conveying duct to the upper, reserve chute 43 and the material is driven downwardly by the air pressure onto a feed roll 44. The feed roll 44 cooperates with feed table segments 45 (only one segment is visible in FIG. 11), each being connected to a holding element 15 by separate leaf springs 14a, 14b. Upon thickness variations of the material passing between the feed table segments 45 and the feed roll 44 the respective feed table segment 45 is pushed away from the feed roll 44. Upon such occurrence, the leaf springs 14a, 14b bend and tend to rotate the holding element 15 in a clockwise direction as viewed in FIG. 11. The evaluation of the turning motion of the holding element is effected in a manner similar to the earlier-described embodiments. From the feed roll 44 the fiber batt 19 is admitted by means of an opening roll 47 into the feed chute 46 from which it is advanced onto the transfer plate 39 by a pair of cooperating withdrawing rolls.
In the embodiment illustrated in FIG. 12 the holding element 15 is a hollow extruded member, made for example of aluminum, having hollow spaces 15c and 15d. The oscillation behavior of the feed table segments 2a is an important consideration. If the segments 2a were imparted a frequency close to their natural frequency, they would start oscillating with a natural frequency which would present an uncontrolled movement which would endanger their function. Consequently, the natural frequency of the segments should be as high as possible. Since the natural frequency is primarily dependent from the own flexure, the weight must be held small. For this reason aluminum is selected for the holding element 15. The selection of a light-weight material for the holding element 15 is further advantageous because the reduced weight facilitates the installing operation. Also, the selection of aluminum allows production of the shape of the beam 15 by means of an extrusion process. This eliminates the need for mechanical shaping. Between the holding element 15 and the feed table segments 2a an abutment bar 37 is arranged.
An abutment bar 37 is provided between the holding element 15 and the feed table segments 2a. The abutment bar 37 extends in a space defined by outer top grooves provided in the feed table segments 2a. A cooperation between a side wall of the top grooves and the abutment bar 37 limits the excursion path for each feed table segment 2a. In the holding element 15 throughgoing grooves 55a, 55b are provided which have a T-shaped cross section and each accommodates a respective fastening rail 56a, 56b for fastening the leaf springs 14a, 14b by means of screws 57a, 57b.
In the embodiment shown in FIG. 13 the lower ends of the leaf springs 14a project downwardly beyond the lower end of the feed table segments 2a by a distance a. The leaf springs 14a which are made of hardened steel form in the zone of the narrow transition gap wear-resistant elements exerting a high pressing force. In this zone the leaf springs 14a are in direct contact with the fiber material.
The embodiment according to FIG. 14 has a one-piece feed table 2. The holding element 15 (summing beam) is also a throughgoing, one-piece element and is rotatably held with respect to the stationary machine frame for performing measurements. An abutment and securing strip 58 is provided, whose part 58b clamps a series of leaf springs 14a against the holding element 15, for example, by means of screw connections. The part 58a of the securing strip 58 is at a clearance b to the leaf springs 14a so that this zone 58a provides an abutment for the leaf springs 14a to limit their excursions away from the feed roll 1. The leaf springs 14a also serve as clamping springs for the fiber material. The free ends of the leaf springs 14a may swing away from the frontal face 2' of the feed table 2.
In the construction shown in FIG. 15a the one-piece feed table 2 is resiliently held relative to the machine frame. For this purpose a spring 59 is provided so that a deviation in case of thickness variations of the fiber batt and the generation of a signal for monitoring the material thickness and the regulation of the material supply is possible.
According to the embodiment illustrated in FIG. 15b the feed table 2 is stationarily held while the feed roll 1 is resiliently supported with the aid of a spring 60. With the feed table 2 leaf springs 14a are associated.
In the embodiment shown in FIG. 16 the feed table 2 is, with the aid of springs 61a, 61b, supported resiliently relative to the holding element 15.
In FIG. 17 which shows a structure similar to FIG. 16, the feed table 2 is at one end pivotally secured to the machine frame with the aid of a pivot bearing 62.
In the embodiment illustrated in FIG. 18a the feed table 2 is supported in a guide 63 allowing the feed table to execute horizontal displacements as indicated by the arrows I, K. This arrangement prevents a vertical motion component of the feed table and thus the inductive path sensor 22 senses only the horizontal displacements of the feed table 2. At one end of the feed table 2 a tension spring 64 is provided to urge the feed table in the direction of the arrow I and to thus provide a pressing force on the fiber material in cooperation with the feed roll 1. FIG. 18b illustrates the excursions of the leaf springs 14 of the FIG. 18a embodiment towards and away from the surface 2' of the feed table 2, as indicated by the arrows L and M.
FIGS. 19a-19d show various embodiments concerning the location of rotary support for the feed table 2. According to FIG. 19a, the feed table is supported at one end by means of springs 66. A pivot pin 65 is provided in the zone of the leaf springs 14a at the frontal end of the feed table 2 to be received in a bearing socket (not shown). In the structure according to FIG. 19b, the feed table 2 is supported by springs 67 in the zone of the leaf springs 14a at the frontal end and at the rear terminus the feed table 2 is rotatably supported by a pivot pin 66. FIG. 19c shows an embodiment similar to FIG. 19a in which, however, the pivotal support 68 is situated above the feed table 2. In FIG. 19d the construction is similar to that of FIG. 19b in which, however, the pivotal support 69 is situated in approximately the lateral middle of the feed table 2.
In the embodiments of FIGS. 18a, 19a-19d the excursion of the leaf springs 14a imparts a force on the feed table 2 which functions as a summing beam and whose linear shift (FIG. 18a) or rotation (FIGS. 19a-19d) is measured. It is noted that the springs 59, 60, 61a, 61b, 64, 66 and 67 are harder than the leaf springs 14a which form the sensor elements.
Advantageously, the apparatus may also be used as laboratory instrument for determining the cleanability of cotton.
It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims. | An apparatus for feeding a fiber batt to a fiber processing machine includes a feed roll; a feed table formed of a plurality of separately movable feed table segments each cooperating with the feed roll and defining therewith a nip through which the fiber batt passes; a plurality of springs each being affixed to the feed table segment to form integral components therewith; and an elongated holding element extending spaced from, and generally parallel to the feed roll. Each spring is affixed to the holding element. The feed table segments are individually movable away from the feed roll against a force of respective springs in response to thickness variations in the fiber batt as the fiber batt passes through the nip. There is further provided a support for rotatably supporting the holding element. The feed table segments impart torques on the holding element through the respective springs as a function of movements of the feed table segments and the holding element is rotated by the torques to an extent representing a sum of the torques. A sensor is connected to the holding element for generating a signal as a function of rotary displacements of the holding element. | 3 |
RELATED APPLICATION
The present application is a continuation application of co-pending application Ser. No. 13/251,807 filed Oct. 3, 2011; which is a continuation application of application Ser. No. 12/835,100 filed Jul. 13, 2010 and issued as U.S. Pat. No. 8,042,407 on Oct. 25, 2011; which is a continuation application of application Ser. No. 12/506,986 filed Jul. 21, 2009 and issued as U.S. Pat. No. 7,775,121 on Aug. 17, 2010; which is a divisional application of application Ser. No. 12/017,413 filed Jan. 22, 2008 and issued as U.S. Pat. No. 7,578,201 on Aug. 25, 2009; which is a divisional application of application Ser. No. 11/283,022, filed on Nov. 17, 2005 and issued as U.S. Pat. No. 7,343,816 on Mar. 18, 2008; which is a divisional application of application Ser. No. 10/443,193, filed on May 22, 2003 and issued as U.S. Pat. No. 6,993,981 on Feb. 7, 2006; which claims priority from U.S. Provisional Application Ser. No. 60/383,023, filed on May 24, 2002; all of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
The invention relates generally to the field of tension monitoring during installation of underground utilities. As an example, the method and apparatus of the present invention may be used in the tension monitoring arrangement described in U.S. Pat. No. 5,961,252 (hereinafter the '252 patent) which is incorporated herein by reference. FIG. 3 of the '252 patent illustrates an installation operation in progress during which a utility is pulled through a previously formed pilot bore. Tension is monitored using a tension monitoring arrangement 60 . FIG. 5 of the '252 patent schematically illustrates the tension monitoring arrangement used in the operation of FIG. 3 .
SUMMARY OF THE INVENTION
As will be described in more detail hereinafter there is disclosed herein a system for installing an underground utility by retraction that is applied to a leading end of the utility to draw the utility through the ground such that the utility is subjected to a tension force.
In one aspect of the present invention, a sensing arrangement is used for sensing the tension force that is applied to the leading end of the utility to produce a sensor signal. An amplifier arrangement uses the sensor signal to generate an amplified output signal. A compensation arrangement applies a compensation voltage to the amplifier arrangement for shifting the amplified output signal.
In another aspect of the present invention, the system includes an inground tension monitoring arrangement having a processing arrangement which receives electrical power from a power supply in a way which may subject the processing arrangement to a loss of power that is temporary during system operation, as well as a shut-down loss of power condition, either of which causes the processing arrangement to reset. The system further includes a first arrangement for producing an output signal that is responsive to a time duration of the loss of power. A second arrangement cooperates with the processing arrangement for using the output signal to establish whether a particular reset is responsive to a power supply bounce condition during operation. In one feature, the processing arrangement is configured for saving at least one system start-up parameter at an initial system start-up and is further configured for re-entering a run mode responsive to establishing that the particular reset is responsive to the power supply contacts bounce condition, while retaining the system start-up parameter.
In still another aspect of the present invention, the system includes a sensing arrangement for inground sensing of the tension force that is applied to the leading end of the utility to produce a sensor signal such that a zero tension sensed value may be offset from a zero voltage. An amplifier arrangement uses the sensor signal to generate an amplified output signal such that a zero tension amplified output is produced responsive to the zero tension sensed value. Processing means is configured for measuring the amplified output signal at least in a way which measures the zero tension amplified output responsive to powering on the sensing arrangement and the amplifier arrangement, and for saving the zero tension amplified output. In one feature, the processing means is configured for issuing a ready for calibration signal after saving the zero tension amplified output and the system includes inground transceiver means for transmitting the ready for calibration signal to an above ground location.
In yet another aspect of the present invention, a tension monitoring apparatus is provided including sensing means for inground sensing of the tension force that is applied to the leading end of the utility to produce a sensor signal during the installation time period. Data means is used at least for storing an original digital data set responsive to the sensor signal, during the installation time period and for copying the original data set to a different data location to create a copied data set after the installation time period. A user interface arrangement, in communication with the data means, permits erasing the original data set only after the original data set has been copied to the different data location. In one feature, the data means is configured for creating the original data set in a way which provides for detection of any alteration of the copied data set at the different data location.
In a further aspect of the present invention, a tension monitoring apparatus includes sensing means for sensing the tension force to produce a tension signal. Electronic means is provided for using the tension signal. Battery means is provided for supplying electrical power to the electronic means. Housing means supports the sensing means in a way that exposes the sensing means to the tension force and further defines an elongated chamber between a pair of opposing, first and second ends. The housing means being electrically conductive and a first one of the ends being configured for receiving the tension force such that the tension force is transferred through the housing means to the second one of the ends for then transferring the tension force to the utility. The electronic means is positionable in the chamber with the battery means such that the housing means serves as at least a portion of an electrical circuit for supplying the electrical power to the electronic means from the battery means. In one feature, the electronic means is further configured for at least one of recording the tension force, based on the tension signal, and transmitting the tension force to an aboveground location. In another feature, the elongated chamber is at least generally cylindrical in shape having a chamber diameter that is defined by an interior chamber surface and the battery means includes at least one battery cell that is cylindrical in shape so as to define an outer cylindrical surface and the battery cell is received in the elongated chamber such that the outer cylindrical surface of the battery cell is supported directly against the interior chamber surface.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be understood by reference to the following detailed description taken in conjunction with the drawings briefly described below.
FIG. 1 is a schematic diagram of one embodiment of the tension monitoring arrangement of the present invention, shown here for purposes of illustrating its highly advantageous configuration.
FIG. 2 is a flow diagram which illustrates one embodiment of a highly advantageous start-up and calibration procedure in accordance with the present invention.
FIG. 3 is another flow diagram which illustrates one embodiment of run mode in accordance with the present invention.
FIG. 4 is an partial cutaway view of one embodiment of the highly advantageous tension monitoring arrangement of the present invention, shown here to illustrate details of its structure.
FIG. 5 is a perspective view of a first end fitting that is used in the tension monitoring arrangement of FIG. 4 , shown here to illustrate details of its structure, particularly with respect to providing battery power to an electronics package that is housed within the tension monitoring arrangement.
FIG. 6 is a perspective view of a second end fitting that is used in the tension monitoring arrangement of FIG. 4 , opposite the first end fitting of FIG. 5 , shown here to illustrate details of its structure, again with respect to providing battery power to an electronics package that is housed within the tension monitoring arrangement as well as positioning and support of strain gauges that are used to sense tension force being applied to a utility.
FIG. 7 is another perspective view of the second end fitting of FIG. 6 , shown here to illustrate further details of its structure.
FIG. 8 is a perspective view of the end fitting of FIGS. 6 and 7 shown positioned adjacent to the electronics package.
FIG. 9 is a diagrammatic view, in elevation, shown here to illustrate the use of the tension monitoring arrangement of the present invention in a winching configuration.
FIG. 10 is a diagrammatic view, in elevation, shown here to illustrate the use of the present invention for monitoring tension as applied by a crane.
DETAILED DESCRIPTION OF THE INVENTION
Turning now to the figures of the present application, wherein reference numbers of the ' 252 patent have been applied to like components where possible, attention is immediately directed to FIG. 1 . This figure illustrates a portion of the arrangement of components shown by FIG. 5 of the ' 252 patent including strain gauge arrangement 82 (within a dashed box), battery 87 , power supply 88 and CPU 92 . Additional components are shown including a multiplexer 100 , an analog to digital converter (A/D) 102 , a digital to analog converter (D/A) 104 , a differential amplifier arrangement 106 (within a box) having (+) and (−) inputs that are connected to strain gauge arrangement 82 at P 1 and P 2 , respectively. It is noted that component additions may not be required, in order to practice the present invention, where previously installed components have unused capacity which may be pressed into service. For example, multiplexer 86 of FIG. 5 in the ' 252 patent may serve in place of multiplexer 100 of FIG. 1 of the present application. In this regard, identity of components is not required so long as functional equivalence is achieved in view of the teachings herein. It is noted that the plus (+) and minus (−) amplifier input markings were inadvertently reversed in FIG. 1 of the above incorporated provisional application. While this has been corrected, along with a few typographical changes in this description, it is submitted that one of ordinary skill in the art would immediately reverse the markings in view of the functionally described differential amplifier configuration that is clearly in use.
Continuing to refer to FIG. 1 , strain gauge arrangement 82 is made up of strain gauges S 1 -S 4 in an H bridge configuration. As an example, in considering tension monitoring, strain gauges S 1 and S 4 may be oriented along the axis of pull with S 2 and S 3 oriented orthogonal thereto. Accordingly, S 1 and S 4 stretch responsive to pulling the utility being installed. Voltage at P 1 will decrease, while voltage at P 2 will increase. The decrease and increase in voltages at these respective connections comprise inputs to differential amplifier 106 which, in turn, cooperate to provide an output responsive to tension. This tension output is sent to multiplexer 100 channel 3 input on a line 110 for conversion to digital form and is selectively available to processor 92 . Strain gauges S 2 and S 3 , in the present example, being oriented orthogonally with respect to the axis of pull, are not subjected to pulling tension but may be used advantageously for purposes such as temperature compensation. Of course, the present invention contemplates that alternative arrangements of the various strain gauges may be employed which result in different tension orientations with respect to each individual one of the strain gauges.
While it is sometimes desirable for strain gauge arrangement 82 to provide a voltage output of zero volts in the absence of any pulling tensions, it should be appreciated that such a strain gauge arrangement typically does not exhibit a zero offset. That is, the output at zero pull taken between P 1 and P 2 is offset from the desired zero volt value, as provided to the inputs of differential amplifier arrangement 106 . Moreover, as will be seen, it may at times be desirable to provide an offset voltage at the input of the differential amplifier arrangement for purposes of increasing dynamic range, for example, with respect to pulling force. These and other desired offset conditions are encompassed by the concept of a compensation offset signal to be provided to the input of the differential amplifier in a way which produces a desired offset in the output of the differential amplifier, as described immediately hereinafter.
Still referring to FIG. 1 , a compensation line 112 is connected from digital to analog converter 104 to the connection point between S 3 and S 4 (P 2 ) and is thereby capable of influencing one input of the differential amplifier arrangement in a desired manner so as to provide a compensation offset signal. In this way, a target offset value can be provided at the input of the differential amplifier arrangement. For example, microprocessor 92 may provide digital data to digital to analog converter 104 which then provides an analog voltage output that is tailored to cause the differential amplifier arrangement to output a value of zero volts despite an offset voltage at the output of the strain gauge arrangement. Generally, in this arrangement, the (+) input of the differential amplifier is biased at approximately one-half of the power supply voltage.
Moreover, it should be appreciated that compensation line 112 may readily be used to apply compensation in a way that produces some other desired target offset in the output of the differential amplifier. For instance, the desired offset may be intended to increase dynamic range. That is, for example, where only tension monitoring is of interest, an offset at the differential amplifier inputs may deliberately be produced which allows the voltage that is induced by tension in the strain gauge arrangement to produce a larger voltage swing in a known direction. As a specific example, the (+) input of the differential amplifier may be biased downward to a value that is less than one-half of the supply voltage value for this purpose. Accordingly, highly advantageous offset compensation has been provided.
During any pulling operation directed to installing an underground utility, the tension monitoring arrangement may be subjected to significant values of mechanical shock and/or vibration. Where battery 87 is installed in a battery compartment and may be comprised of one or more cells which are spring biased toward one another, it should be appreciated that momentary power interruptions or disconnections may be induced by such shock and vibration. It is recognized herein that such momentary power interruptions may produce conditions under which microprocessor 92 is reset during the drilling operation. In this regard, system calibration with respect to pulling tension is generally performed at system startup under controlled conditions with one or more selected values of tension applied to the drill string and the tension monitoring arrangement. It is further recognized that startup procedures may be initiated responsive to a battery bounce reset in the absence of appropriate provisions. For example, a start-up calibration procedure might be initiated which could replace valid calibration data or zero offset with erroneous data. The apparatus and method of the present invention are configured for advantageously distinguishing such momentary power disconnections from initial power up or start up conditions, as will be described immediately hereinafter.
Continuing to refer to FIG. 1 , a highly advantageous detection arrangement 200 is illustrated within a dashed line. Detection arrangement 200 includes resistors R 1 -R 3 , diode D 1 and a capacitor C 1 . It is considered that one of ordinary skill in the art may readily select component values in view of this overall disclosure. This detection arrangement serves the purpose of distinguishing between momentary power interruptions and system start up conditions. To that end, when battery 87 is connected to the system at start up, the battery will charge C 1 through R 1 and the diode D 1 . If it is assumed that R 1 is about the same resistance value as R 2 , and the time constant provided by the product R 2 *C 1 has a value of about a few seconds, when battery 87 is removed from the system for more than a few seconds (i.e., a shutdown condition), R 2 will discharge C 1 , and the voltage to multiplexer 100 via A/D converter 102 will be proportional to (1−exp(−t/(R 2 *C 1 )), where t is the time in seconds. In this instance, the voltage on the channel 1 input of multiplexer 100 will be less that some predetermined threshold value based on system parameters. On the other hand, when the battery bounces, causing a system reset, the voltage at R 3 (pin 1 of multiplexer 100 ) is about ½ of battery voltage minus one diode drop across D 1 such that the voltage seen by the microprocessor is significantly higher than that voltage which is read after a system start up condition. Accordingly, when the microprocessor reads A/D 102 after a power-on reset or reset(s) due to battery bounce, it is able to distinguish between a just installed battery (low voltage at C 1 ) and a reset caused by battery bounce (C 1 voltage will be close to steady state voltage).
In accordance with the present invention, a startup calibration procedure or zero adjust offset measurement is applied only after the system is powered up and microprocessor 92 detects that the voltage at C 1 is sufficiently low. That is, the voltage is detected before C 1 is able to charge to a value above a predetermined minimum threshold through R 1 indicating a start-up condition. As will be seen, the method employs an auto-zero on startup feature as well as a tension calibration feature using one or more non-zero tensions applied to the tension monitor.
Turning to FIG. 2 , a highly advantageous start up and calibration method is generally indicated by the reference number 300 . Method 300 is initiated at power-up step 302 . Step 304 then measures the output of differential amplifier arrangement 106 with zero tension applied to the tension monitoring arrangement and stores the offset value. Thereafter, a “Ready for Calibration” message is transmitted in step 306 to an aboveground location which may comprise a receiver at the drill rig or a test fixture specifically directed to that purpose.
The receiver or test fixture then originates a response which may be referred to as a calibration signal. Step 308 is performed at the tension monitoring arrangement in which the latter listens for the calibration signal at a periodic interval. Step 310 tests for receipt of the calibration signal. As the system awaits the calibration signal, operation is transferred through decision step 312 which itself tests for the expiration of an overall time out interval anticipating receipt of the calibration signal. Where the time out interval has not expired, operation returns to step 308 . Steps 308 , 310 and 312 are continuously executed in a loop until expiration of the time out interval. Following expiration of the time out interval, step 314 sends a calibration time out message to the aboveground receiver, followed by step 316 in which operation is transferred into a normal run mode with the new zero offset value, an implementation of which is described below.
Returning to the description of step 310 , when the calibration signal is received, step 318 is entered in which zero tension is applied to the drill string and tension monitoring arrangement. Step 320 then adjusts the output of digital to analog converter 104 so as to generate the compensation signal on line 112 to produce a target value output from the differential amplifier at the channel 3 input of multiplexer 100 . The output of the digital to analog converter is adjusted repetitively until the target value is achieved. Thereafter, settings of the digital to analog converter which achieved the target value are stored by step 322 in nonvolatile memory. In step 324 , tension applied to the tension monitoring arrangement by the drill string is adjusted to a nonzero value for calibration purposes. For example, a tension of 40,000 pounds may be applied to the tension monitoring arrangement. With this tension applied, step 326 is performed wherein microprocessor 92 selects the channel 3 input of multiplexer 100 to read the output of differential amplifier, as converted to digital form by analog to digital converter 102 . In this regard, it should be appreciated that strain gauge response is at least generally linear. Therefore, a calibration constant may be obtained using a single nonzero tension value, however, it is to be understood that additional nonzero tension values may readily be used. With one or more nonzero tension values in hand, step 328 determines a calibration constant k for use in determining tension based on output of the differential amplifier. The calibration constant being determined as:
k
=
applied
tension
(
A
/
D
reading
@
tension
)
-
offset
Step 330 stores calibration constant k in nonvolatile memory. A “calibration complete” message is then transmitted, in step 322 , to the receiver at an aboveground location such as, for example, receivers R 1 and R 2 , as shown in FIG. 2 of the ' 252 patent, a drill rig receiver or a test fixture receiver.
FIG. 3 illustrates one potential implementation of the run mode, generally indicated by the reference number 400 and entered at step 402 . In step 404 , a measurement interval or period is initiated for the duration of which tension is monitored. In step 406 , a tension value is measured by microprocessor 92 using the voltage value obtained from the channel 3 input of multiplexer 100 and the stored zero offset value. Step 408 may transmit this tension value, for example, to an aboveground receiver for use in displaying the tension value to an operator, comprising a display which is presented essentially in real-time. Step 410 determines whether the tension value just measured is a new maximum tension for the measurement interval which is currently underway. If the tension value is a new maximum, step 412 saves that value in a data set corresponding to the current measurement interval in a way which is described in further detail hereinafter.
If the tension value just measured is not a new maximum tension value for the interval underway, step 414 tests whether the measurement interval has concluded. If the measurement interval is ongoing, the process repeats, beginning with step 406 . If, on the other hand, the current measurement interval has concluded, step 416 determines whether the overall installation operation has concluded. In the event that the installation operation is continuing, the process resumes by initiating a new measurement interval at step 404 and determining a maximum tension value for the new interval, as described above. If step 416 determines that the installation has concluded, step 418 initiates an upload procedure in which the data set produced by step 412 is copied to another location in a protected manner. Following the upload procedure of step 418 , the data set may be erased in step 420 using step 422 . Stop step 424 concludes the run mode. It should be appreciated that this installation procedure is advantageous at least for the reason that even a long installation run produces a data set of relatively limited size, since maximum interval values are stored. Moreover, the system may readily present an overall maximum value that is selected from the interval maximums. Of course, the data set may be presented in any number of suitable manners.
It should be appreciated that run mode procedure 400 does not afford an opportunity to alter or erase the data set prior to upload. Moreover, it is desirable to protect the data set from unauthorized alteration. In this regard, any number of techniques currently available or yet to be developed, may be employed even during step 412 , which creates the data set and adds new values to it to prevent and/or detect data alteration. For example, the data set may be subjected to cyclic redundancy checking (CRC) wherein even the modification of a single bit is readily detected. Moreover, proprietary formats may be used or developed which may include encryption, either currently available or yet to be developed, that essentially eliminates the possibility of data alteration. In addition to proprietary formats, proprietary devices may be used to initially store the data set and/or to receive the upload of the data set. It is recognized herein that access to the data set is not particularly of concern so long as alteration of the data set is prevented.
Turning now to FIG. 4 , a tension monitoring arrangement produced in accordance with the present invention is generally indicated by the reference number 500 . Arrangement 500 includes a housing 502 having a transmitter arrangement 504 positioned therein. Housing 502 defines an innermost passage having a diameter which is sized to receive a pair of batteries 506 that are connected in series. In this particular example, D cell batteries are used, however any suitable type of battery may be used. Power is supplied to transmitter 504 at the end of one of the batteries nearest the transmitter using a spring biasing and electrical contact arrangement 508 which forms part of the transmitter arrangement, as will be seen in further detail in a subsequent figure. Opposing ends of the housing are closed using a pair of plug arrangements indicated by the reference numbers 510 and 512 , each of which defines a pulling eye 514 .
Referring to FIG. 5 in conjunction with FIG. 4 , plugs 510 and 512 are similar in defining a through hole 516 ( FIG. 5 ) that is configured for receiving a pin 520 ( FIG. 4 ) through cooperating holes defined in housing 502 so as to hold the plugs in position. O-ring seals 522 ( FIG. 5 ) are used to seal the plugs against housing 502 .
Plug 512 includes a spring contact arrangement 523 made up of a housing contact spring 524 and an inner, battery contact spring 526 both of which are best viewed in FIG. 5 . Housing 502 defines a recess that is configured for receiving housing contact spring 524 so as to form an electrical contact between the housing contact spring and housing 502 . Battery contact spring 526 places a resilient bias against a nearest one of batteries 506 and forms an electrical contact with its end terminal. At the same time, battery contact spring 526 is electrically connected to plug 512 .
Referring to FIGS. 4 , 6 and 7 , plug 510 is illustrated including its highly advantageous configuration with respect to delivering power to transmitter arrangement 504 from batteries 506 . To that end, plug 510 includes a fastener receptacle 530 which may be configured for receiving a threaded fastener 532 or any suitable type of fastener. An electrical connection such as, for example, a wire 534 provides an electrical connection to transmitter arrangement 504 . Any number of different forms of electrical connection may be employed as an alternative between plug 514 and the transmitter including, for example, spring biasing. A recess 536 is formed in the sidewall of plug 510 for receiving a coil spring 538 ( FIG. 6 ). When plug 510 is installed in housing 502 , spring 538 is captured between the plug and housing so as to form an electrical connection therebetween. It should be appreciated that additional recesses 536 and springs 538 may readily be used to enhance electrical connectivity.
In view of the features described above, electrical power is supplied from the battery using housing 502 in cooperation with end plugs 510 and 512 in a highly advantageous manner. In particular, this configuration, wherein the housing is used as an electrical path, optimizes the strength of the housing by avoiding the need for a separate battery compartment which would result in reduced thickness of the housing wall and by allowing for greater battery diameter and thereby increased power capacity.
FIG. 8 illustrates plug 510 positioned adjacent to transmitter 504 to further illustrate details of its structure including spring biasing and electrical contact arrangement 508 .
It should be appreciated that the highly advantageous tension monitoring arrangement of the present invention may be used in systems other that in conjunction with being pulled using a drill rig and drill string. FIG. 9 diagrammatically illustrates one such alternative system generally indicated by the reference number 650 . System 650 includes a winch 652 arranged for pulling a winch cable 654 . The latter is attached to tension monitoring arrangement 500 in a way which transfers winching tension to a cable extension 656 that is attached to a pulling object 658 . This attachment may be accomplished, for example, using a Kellum's grip, as is known in the art. Pulling object 658 may comprise any suitable elongated member including an electrical power cable or pipe. The objective of the task may be, for example, to pull the elongated member through a pathway, shown in phantom using a dashed line, that is defined, for example, by a conduit or raceway either underground, aboveground, in a building or otherwise. Upon completion of the installation, the tension data set can be downloaded as described above. If desired, tension monitoring arrangement 500 may transmit an electromagnetic signal 672 which may include, for example, real time tension values. Signal 672 may be received by an antenna 674 of a portable receiver 676 . The latter may include any suitable form of a display 678 for illustrating the tension value. Moreover, aural and/or visual warnings may be provided, if a maximum tension is about to be exceeded.
Attention is now directed to FIG. 10 for purposes of further describing the broad range of tension monitoring tasks to which the tension monitoring arrangement of the present invention is well-suited. In particular, a crane 700 is diagrammatically illustrated having a lifting cable 702 wherein tension monitoring arrangement 500 is installed so as to be subjected to all lifting forces that are applied to a hook 704 . Again, tension data can be downloaded at the conclusion of a particular task. If desired, a receiver 706 may be located in a cab 708 of the crane for receiving transmitted data 672 from tension monitoring arrangement 500 so as to provide a crane operator (not shown) a real time display 712 of lifting force.
Since the system and apparatus of the present invention disclosed herein may be provided in a variety of different configurations and the associated method may be practiced in a variety of different ways, it should be understood that the present invention may be embodied in many other specific ways without departing from the spirit or scope of the invention. For example, it is to be understood that the described apparatus and methods, are not limited to use in tension monitoring configurations, may be practiced in many other alternative and equivalent forms relating, for example, to offset compensation, resolving battery bounce conditions, as well as related reset considerations, data set protection and the use of a housing for power supply purposes with attendant advantages. Therefore, the present examples and methods are to be considered as illustrative and not restrictive, and the invention is not to be limited to the details given herein, but may be modified within the scope of the appended claims. | Tension monitoring is described using a sensor which may exhibit an offset for which compensation may be provided to produce a zero voltage amplified output or to increase dynamic range. An arrangement determines whether a power reset is responsive to a battery bounce such that an initially-measured system start-up parameter can be retained. The start-up parameter is automatically saved at start-up if the power reset is responsive to a start-up from a shut-down condition. The start-up parameter may be a zero tension amplified output responsive to the sensor offset at zero tension. Protection of a tension data set is provided such that no opportunity for altering the data set is presented prior to transfer of the data set. A housing configuration forms part of an electrical power circuit for providing electrical power to an electronics package from a battery. | 6 |
BACKGROUND TO THE INVENTION
The invention relates to the dewatering of naturally moist crude peat. Particularly, it relates to a method which can reduce the water content of crude peat to a level at which the peat is relatively easily combustible, in a single continuous process.
Dewatered peat may be used, for example, for heating purposes. For this application, a naturally moist crude peat from a peat bog with a water content of the order of 90% and over must be dewatered, and to be combustible without auxiliary heating, normally to a level of 45% to 55% water by weight depending on its quality; i.e., depending on the respective calorific value of its dry substance.
In one original method, peat was dewatered by piling the peat into mounds, and then into a so-called stacks which are left to dry in the open air, for an unforseeable length of time. Such a method was totally dependent upon the weather, and the amount of drying time required could not be foreseen. In a more modern method, the peat is given a preliminary dewatering mechanically by means of a press to a residual moisture content of 60% to 70% by weight and is then dried in the air if necessary. This method, also, is largely dependent on the weather and, like the previously mentioned method, takes up large storage areas and unforeseeably long drying times.
For industrial heating, whenever peat must be continually available as a fuel in large quantities, a proportion of another fuel with an higher calorific value can be added to a mechanically dewatered peat to form a self-combustible mixture, or a peat which has been given a preliminary dewatering is loaded onto a heating layer of a fuel of higher calorific value for combustion. As such fuels, coal, oil or gas can be used.
Peat which has been given a preliminary dewatering can also be dried thermally, for example in a fluidized bed drier, into a self-combustible product. The self-combustible peat obtained in this way is normally subsequently burned in a furnace, and a portion of the heat thus obtained may be drawn back off to heat the drier. In this process, approximately 50% of the available calorific value of the peat is lost on evaporation of the water in the drier.
The methods mentioned above are not very economical, because on evaporation of the high proportion of water of the peat which is to be burned in this way, a large proportion of its calorific value is lost, usually at least 800 Kcal for 1 liter of water evaporated.
A peat having a residual moistness of 45%-55% water can also be produced through so-called blending, in which a more moist peat, containing for example 60%-70% water--, is mixed with a drier peat; e.g., containing about 20% water obtained from other sources of supply. A desired average moistness of, for example, 45%-55% can be obtained in this way.
A further disadvantage of known dewatering techniques is that the dewatered peat is a loose, light, spongy bulk material, the transportation and storage of which not only take up large volumes, but is also extremely difficult. Further, it is expensive and dangerous because of the fire risk and the possibility of explosion. In addition, the peat continues to dry naturally; the fibres become brittle and fragile; and breaking of the fibres results in a powdery peat of poorer quality because of the damaged structure if it is used, for example, to improve cultivated ground. For these purposes, fibrous peat is required which, so far as possible, maintains its original, natural structure.
It is intended to use peat in large quantities for the reconstitution of areas which have been transformed into steppe or arid areas; e.g., on various such technical agricultural programmes in developing countries. An obstacle to all this is the hitherto unsolved question of economical and safe transportation of large quantities of peat over large distances.
It is indeed known to pack the peat--by whatever way it has been dewatered--in bales in plastic bags for transportation, which facilitates handling and restricts further drying out. This method is however costly, such that it is only justifiable today in the field of the relatively small requirement for horticulture. In terms of volume, it only entails small advantages in transportation, so that transportation over long distances, even by sea, would be very or too expensive.
SUMMARY OF THE INVENTION
According to the present invention a method of dewatering naturally moist crude peat comprises passing the crude moist peat through a first dewatering press to produce an intermediate product with a reduced water content; and further dewatering the peat in stages in a filter press system having at least two successive filter press chambers, the respective filter cake being loosened in passage between the filter press chambers, and compacted in the final dewatering stage. In the final stage, the peat can be compacted to peat fibre briquettes or slabs. Slabs may be cut or prepared into pieces which can be readily packaged or palletted.
The method of the invention can be operated to produce dewatered peat continuously and, if required, in large quantities. The produce may be in a compacted, cohesive form, which in terms of volume represents a fraction of the natural volume of the peat, and in this way the original structure of the fibres of the peat can be substantially retained. To a large extent they are undamaged, which means they can remain essentially unbroken.
A typical naturally moist crude peat contains over 90% water by weight and in a method according to the invention is dewatered in the first dewatering press to an intermediate product having 60% to 80%, preferably 60% to 70% water by weight. In the subsequent pressing phases the water content can be reduced to 45% to 55% by weight.
Apparatus for carrying out the method of the invention can use, in the first dewatering phase, a double machine wire press with a plurality of pairs of pressing rolls arranged along the dewatering strip of the press, and in the subsequent filter press system at least two filter press chambers arranged above each other, commanded according to the same working cycle. Using such apparatus, 1 liter of water can be withdrawn from the peat with an energy expenditure of approximately 50 Kcal. The dewatering method of the invention is therefore substantially more economical than the dewatering processes previously known, and referred to above.
In the method of the invention, the natural structure of the peat fibres need not be destroyed. The pressing can be controlled such that it takes place only within the framework of the elasticity available in each case, in relation to the moistness of the fibres. Even during the final dewatering stage their elasticity is such that compacting can take place without breaking of the fibres. The last pressing stage, as the dewatering is completed, can be controlled such that the point is reached, as regards the moistness of the fibres, where their elasticity is lost and therefore the form obtained is substantially stable.
The product obtained can be stacked and further stored, and can continue to dry out naturally, without the threat of fire or explosion through spontaneous ignition. It can be expediently prepared for transportation; e.g., loaded on transportation pallets. Its volume is a fraction of the originally natural volume of the raw peat.
In order to be used for agricultural applications discussed above, after being transported over a long distance, the dewatered product may be rewatered or moistened back again with water, whereby the original high elasticity, caused by a degree of moistness, is reproduced in the undamaged fibres. The reconstituted peat is then in a condition, for example, to be worked into the earth to improve the ground.
BRIEF DESCRIPTION OF THE DRAWING
The invention will now be described, by way of example, and with reference to the accompanying drawing which shows schematically an installation in which the method may be carried out. Further advantages and benefits of the invention will be apparent from the following description thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A naturally moist crude peat having a water content of say 90% by weight, extracted from a peat bog, is delivered from tipping cart 1 via a conveyor device 2, to a first dewatering phase. This takes place by means of a continuously operating dewatering press A. In the installation illustrated, it is a double machine wire press with a lower machine wire 3 and an upper machine wire 4, between which a dewatering strip 5 is formed, which is arranged along a plurality of pairs of pressing rolls 6,6. This double machine wire press is an apparatus known per se, in which the crude peat is dewatered under gradually increasing pressure, between the successive pairs of pressing rolls, so that an intermediate product, which is obtained after the final pair of pressing rolls 7,7, has a proportion of water of 60% to 70% by weight. With the apparatus proposed in the installation shown, an intermediate product with this proportion of water can be readily expected. A double machine wire press such as this is described, for example, in British patent specification No: 2 097 277A (application No: 82 12180).
The intermediate product is transferred via a transportation path 8 into a subsequent pressing phase. In this subsequent pressing phase, the product is further dewatered to the desired residual moistness of 45% to 55% by weight. This dewatering takes place in batches and stages in at least two successive filter press chambers, whereby the respective filter cake is loosened and shifted on the path from the one filter press chamber to the next.
In the installation shown, to carry out the subsequent pressing phase, a filter press system B is used, which operates as follows:
The intermediate product arrives from the transportation path 8 into a first sprinkling device 9, through which it is sprinkled and piled onto a first machine wire 10. The machine wire 10 leads through a first filter press chamber 11, through which also a second machine wire 12 is carried, so that the layer of peat to be pressed, which is approximately 100 mm high, lies between the two machine wires and is able to be moved with them in and out to the filter press chamber 11. The second machine wire 12 leads on through a second filter press chamber 13, which is arranged above the first. From there, the machine wire 12 leads back to the first filter press chamber 11. The two filter press chambers 11 and 13 arranged one above the other, are of the same dimensions, and the pressure plates forming and defining them, such as for example the pressure plate designated by 15, are commanded in the same working rhythm; i.e., they are moved in the same working rhythm by means of hydraulically operated motors 14. Thus the relative closing and opening of the two filter press chambers 11 and 13 takes place in the same working rhythm and direction. This means that they are both closed at one and the same interval of time, or are opened simultaneously at another interval of time. The two machine wires 10 and 12 are also moved in the same working rhythm as the filter press chambers: in the interval of time when the two filter press chambers 11 and 13 are opened, the two machine wires 10 and 12 are moved in the direction indicated by the arrows in the drawing. Thus a pressed filter cake is removed in each case from the filter press chamber and a next batch of peat which is to be pressed is carried into the filter press chamber. This takes place with regard to the first filter press chamber 11 in the drawing from left to right and with regard to the second pressing chamber 13 in the drawing from right to left. This movement takes place in the working rhythm in each case by one step, the length of which is equal to the length of the filter press chamber. This applies to the two machine wires and the two filter press chambers, because these have the same dimensions. After this step, the machine wires 10 and 12 remain still and the filter press chambers are closed for pressing. In the following working stroke the filter press chambers are opened and the machine wires are moved on by the length of a step.
The filter press chambers do not need to be confined laterally. The layer of peat which is approximately 100 mm high, is fixed on the machine wires; i.e., within the layer the particles only move in the direction of the pressing force, not transversely thereto. The peat fibres are thereby not damaged.
A filtrate resulting during pressing penetrates through the machine wires and through perforated pressing plates confining the filter press chambers; e.g., one of the pressing plates is designated by 15 and the perforation is indicated by vertical lines,--into collecting chambers which are provided, one of which, for example is designated by 16, and is carried away from there into a filtrate tank 17. The filtrate contains fine particles of peat. Advantageously, the filtrate tank 17 is sunken beneath the filter press B, and is covered with a grid base, so that if the occasion arises, filtrate which is sprayed for example into the surrounding area, and--should the occasion arise--pulverized fine particles of peat, can reach it.
The filter cake moving out of the first filter press chamber 11 on the way to the following, second filter press chamber 13, is loosened and shifted as follows:
The filter cake moving out is taken up, divided and scattered by a scattering reel 18 arranged at the opening of the first filter press chamber 11, and is passed to an elevator 19. The latter transports the material into a second scattering device 20, provided above the plane of the second pressing chamber 13 arranged over the first pressing chamber 11. Through this scattering device the material, which has been loosened and shifted, is scattered and piled onto the second machine wire 12, which leads from here through the second pressing chamber 13. A suitable uniform layer, similar to the case of the first scattering device 9, is obtained here through a pushing back and forth of a scattering belt 21 of the scattering device 20. This movement takes place parallel to the machine wire and is indicated in the drawing by the direction arrows drawn in the scattering belt 21.
The very important loosening and shifting of the filter cake after the first pressing and before the next, which actually cause the desired dewatering effect in the next filter press chamber, therefore occur at the scattering reel 18, in the transportation by the elevator 19 and in the further shifting by means of the second scattering device 20 with the scattering belt 21. The devices used for this must be selected carefully, because in this phase of the process, also, the peat fibres must remain undamaged.
In the next working stroke the material which is piled on the machine wire 12 is carried by this into the second filter press chamber 13 and is pressed for a second time and at the same time is dewatered and compacted. In the following working stroke the pressing chamber 13 is opened and the product 22 which is dewatered to the desired water content of 45% to 55% by weight and compacted to a permanent shape, leaves the installation via a conveyor belt 23.
The uppermost pressing plate 24 of the cycle filter press B is provided with a briquetting form, not shown in the drawing for simplicity's sake, so that at the same time as the pressing the product is briquetted in the second, and here final, pressing chamber 13 and leaves the installation as peat briquettes. It would be possible, should the occasion arise, to add to the material prior to this pressing a suitable binding agent for assisting the briquetting, via the scattering device 20.
If desired, the product could also be prepared into another product form, suitable for transportation. It would be possible, for example, to provide between the second pressing chamber 13 and the conveyor belt 23 a cutting or breaking device, the purpose of which would be to prepare the emerging product cake in the form of a peat fibre plate or slab, which may itself be packagable, or cuttable into easily transportable or palletable pieces; e.g., in the form of broad strips.
As noted above, the filtrate occurring in the subsequent pressing phase is collected in a filtrate tank 17. Together with fine pieces of peat contained therein, it is carried from filtrate tank 17 via a pump 25 and a duct 26 to the start of the first dewatering phase A and there it is mixed together with the fresh crude peat, coming via path 2, which is to be dewatered, and is thus recirculated into the process. Any peat dust which may accumulate after the last pressing stage may also be recycled to the start of the process, and mixed with the fresh natural peat to be dewatered. Thus, these proportions of the substance subjected to the process are not lost.
If the two successive steps described here, which are carried out during the subsequent pressing phase in the two filter press chambers 11 and 13 are not sufficient to achieve the desired degree of dewatering, which could be the case with certain types of peat, it would be possible to arrange further filter press chambers for further pressing steps, between which in each case the loosening and shifting according to the invention would take place. In addition, it would be possible, for example, to connect at the outlet side a second cycle filter press to the cycle filter press described herein, with two filter press chambers arranged one over the other. Between the two presses, however, a corresponding loosening and shifting device would have to be provided.
An important advantage of the process according to the invention lies in that the dewatering both in the first dewatering phase A, and also--and principally--in the subsequent dewatering phase B, is largely independent of temperature. The temperature of the peat or of the material which is to be dewatered, insofar as it obviously lies above the freezing point of the material, has practically no effect on the result of dewatering. In contrast to other known dewatering methods or dewatering devices, we have found that an otherwise conventional heating of the material to obtain a higher degree of dewatering is unecessary, and wasted energy without leading to any better results.
As noted above, the use of binding agents can promote the compacting of the product in the final stage to a permanent shape. The selection of a suitable binding agent is also governed by the purpose to which the product is to be used. For subsequent combustion, for example any synthetic resin material could be used, which would not normally be suitable if the product is intended for technical agricultural purposes. Here, for example, certain water-soluable fertilizers would be used, whether of organic or inorganic origin.
It is possible also in the method of the invention to provide the surface of the compressed product, in whatever form, subsequently with a protective layer, which for example would inhibit a formation of dust on the surface, or would hold dust on the surface. | The invention relates to the dewatering of naturally moist crude peat. In the method disclosed, dewatering is accomplished in stages. In the first stage, the peat is passed through a press (A) to produce an intermediate product which is passed to a filter press system (B) where the peat is further dewatered in at least two successive filter press chambers (11,13). In passage between the press chambers the peat is loosened and in the last dewatering stage (13) the peat is compacted. The resultant product can be handleable and transportable with minimal risk. In addition to being largely independent of weather and temperature, the method is considerably more economical than previous processes which were inefficient in terms of time and/or energy consumption. | 2 |
This is a continuation, of application Ser. No. 779,589 filed Mar. 21, 1977, which was a continuation of Ser. No. 656,592, filed Feb. 9, 1976, both of which are now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a fibrous sheet and more particularly to the so-called internal application of latex in production of a fibrous sheet by known wet paper making technique or wet non-woven fabric making technique which comprises previously flocculating a chlorinated polymer latex into a flocculate of 100-500μ in particle size, adding the resultant flocculate to a fiber slurry which is separately prepared, making the slurry into a sheet and drying the resultant sheet.
The method for internal application of latex is roughly classified into the following two techniques.
(1) The so-called beater addition which comprises flocculating a latex in a fiber slurry to deposite the latex onto the surface of the fibers.
(2) The method which comprises previously producing a flocculate of a latex and adding the flocculate to a fiber slurry which has been separately prepared. (In this case, said flocculate is retained in the sheet by filtering action.)
The present invention belongs to the technical field (2) and a novel method for controlling the particle size of chlorinated polymer latex such as anionic polyvinyl chloride (referred to as "PVC" hereinafter) latex, polyvinylidene chloride (referred to as "PVDC" hereinafter) latex, or combination thereof which has been difficult to attain has been found.
Hitherto, said method (1) which comprises adding a latex to a beater has been carried out in the production of papers and boards. However, according to such method, various troubles in paper making are apt to occur when the latex is added in a great amount of more than 20% by weight of fiber. Therefore, said method (2) has been mainly employed in the production of non-woven fabrics where a large amount of latex is often used.
However, since the retention of the latex in the sheet depends upon only the filtering action, it is needless to say that control of the size of the latex flocculate is very important.
As the result of various experiments by the inventors, it has been found that a flocculate of 100μ-500μ in particle size is optimum although the optimum particle size may somewhat vary depending on the thickness and shape of the fibers.
A large flocculate having a particle size of more than 500μ shows 100% retention, but the resultant sheet has specks and tends to adhere to the surface of drier.
In the case of a flocculate of less than 100μ in particle size, retention is not satisfactory and the necessary strength cannot be obtained and moreover the waste water is markedly contaminated. According to the present invention, novel conditions for flocculation of chlorinated polymer latices such as anionic PVC latex and PVDC latex which are difficultly controlled in particle size of their flocculates have been found.
The particles size of the flocculate is defined as maximum diameter which passes through the center of each flocculate when observed under a microscope.
When anionic PVC and PVDC latices are flocculated with water soluble cationic polymers or polyvalent metal salts by the conventional technique, only such flocculates having a particle size of less than 50μ, mostly 10-20μ are obtained even under a very slow stirring condition. As the result of the inventors' intensive research in an attempt to obtain a stable flocculate of 100μ-500μ in particle size, it has been found that a latex finally becomes a stable flocculate through the following stages.
That is, when a flocculate is produced by adding water soluble cationic polymers or polyvalent metal salt to an anionic PVC or PVDC latex, the latex grows to a flocculate of 1 mm to 10 mm for the first several seconds by the shock of the addition, thereafter redispersion of the flocculate occurs to give the form of grape bunch and then the dispersion becomes a flocculate of about 10 to 30μ in particle size in such a manner that individual grapes fall from the bunch.
It has also been confirmed that the same progress of flocculation as mentioned above follows when an anionic acrylic latex is flocculated with a water soluble cationic polymer under relatively mild flocculation conditions, but what is different from the flocculation of the anionic PVC and PVDC latices is that the acrylic latex is difficulty redisperred into the flocculate finer than the state of the grape bunch and so the floccuate is stabilized in the form of coarse flocculate (200μ to 1 mm). Furthermore, it has also been recognized that in the case of radical flocculation with an aluminum salt, the flocculates of 1 mm to 10 mm produced due to the shock of addition gather to form masses of the flocculate.
From the above results, it has been found that the adhesion power within the flocculate of latex has a remarkable influence on the particle size of the final flocculate and hence the minimum film-forming temperature (abbreviated as "MFT" hereinafter) of the latex holds the key.
SUMMARY OF THE INVENTION
That is, the present invention provides a method for producing a fibrous sheet which comprises heating at least one chlorinated polymer latex such as anionic PVC latex and PVDC latex or combination thereof to a temperature of at least the MFT of said latex, adding thereto a water soluble cationic polymer or a polyvalent metal salt with stirring to produce a flocculate having a particle size of 100μ-500μ, adding thus obtained flocculate to a fiber slurry which is separately prepared, producing a sheet therefrom by known paper making method and drying the resultant sheet.
With increase in the heating temperature than the MFT, the particle size of the final flocculate becomes larger and with decrease in the heating temperature, the particle size becomes smaller. This is because the inner adhesion power of the latex flocculate is increased and redispersion of the flocculate caused by stirring is prevented. Therefore, it is important to previously and experimentally determine the temperature by which a flocculate having a particle size of 100μ-500μ which is suitable for paper making is obtained.
It is clear that after the particle size of the flocculate is stablized, the temperature may be lowered and keeping warm is not especially required.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The chlorinated polymer latex includes anionic polyvinyl chloride (PVC) latex and polyvinylidene chloride (PVDC) latex which are latices emulsified with an anionic surfactant and which are flocculated with a water soluble cationic polymer or a polyvalent metal salt.
Said anionic PVC latex and PVDC latex include not only homopolymers of vinyl chloride or vinylidene chloride, but copolymers of vinyl chloride and vinylidene chloride and copolymers with other vinyl monomers such as vinyl acetate, arcylic esters, etc. or unsaturated acid such as maleic acid, etc. It will be clear that those to which external plasticizer is added to lower the MFT are also included.
Preferably, these latices are diluted to 0.5-10% by weight prior to flocculation and when the concentration is too high, collision of the flocculated particles becomes too violent and coarse mass is apt to be produced.
The water soluble cationic polymers used herein are resins which exhibit cationic property in water. Especially useful resins are polyamide-polyamine-epichlorohydrin resins, polyethyleneimine resins, cationic modified melamine formalin resins, cationic modified urea formalin resins, etc. Many of these polymers are used in the form of an initial condensate and these are also useful as retention increasing agent, wet strength increasing agent and freeness adjusting agent for paper making. Furthermore, cationic modified starch may also be used.
As the polyvalent metal salts, aluminum salts, calcium salts and magnesium salts are especially useful.
Amount of these additives cannot be specified because there are differences in chemical stability of the latex used, but it is sufficient to add in the mimimum amount required for completely flocculate the latex and the amount should not exceed 1.5 time the minimum necessary amount.
The fibers used may be any of natural fibers, regenerated fibers, synthetic fibers, inorganic fibers, metallic fibers, collagen fibers, etc. or mixtures thereof. Furthermore, sizing agent, filler, freeness adjusting agent, dispersion adjusting agent, etc. may also be added in the fiber slurry.
The amount of flocculate to be added to the fiber slurry is 10-300 parts by weight, preferably 10-150 parts per 100 parts of fibers.
The percent of weight and part used herein are all in terms of solid matter unless otherwise specified.
The present invention will be illustrated in the following Examples.
EXAMPLE 1
500 l of 5 weight % diluted liquid of Geon 576 (polyvinyl chloride-acrylate copolymer containing an external plasticizer (dioctyl phthalate) prepared by Nihon Geon K. K. and having a MFT of 50° C.) was heated to 55° C. with stirring in such a manner that no bubbling occurred. To said liquid was added 55 kg of 2 weight % aqueous solution of Polyfix 201 (a polyamide·polyamine·epichlorohydrin water soluble cationic polymer prepared by Syowa Kobunshi K. K.) to obtain a homogeneous flocculate having a particle size of 100μ-500μ.
This flocculate was stable even after allowed to stand for about 50 hours under stirring. Said flocculate was added in an amount as shown in Table 1 to various fiber slurries as shown in Table 1 and fibrous sheets were produced from these slurries by the known wet paper making method and the result sheets were dried. Properties of the sheets are shown in Table 1, namely, they had a high strength and water resistance and had no resin specks on the surface. Furthermore, no troubles occured in paper making procedure.
TABLE 1______________________________________ Pulp 100% Non-woven Synthetic pulp paper fabric paper______________________________________Blending of fibers NBKP NBKP 20 parts Synthetic pulp 100 parts Rayon 80 parts 100 partsLatex flocculate 100 parts 30 parts 100 partsBasis weight(g/m.sup.2) 86.4 51.8 96.2Tensilestrength Dry 4.4 1.8 2.1(kg/15 mmwidth) Wet 1.6 0.9 1.1Elongation Dry 8.8 13.9 69.4(%) Wet 12.3 27.6 51.1MIT folding endur-ance (times) more than more than(load of 1 kg) 10,000 8,000 20,000Cantileverbendingresistance (mm) 130 112 96______________________________________ Note:- (1) "Rayon": 1.5 denier, 10 mm length and produced by Mitsubishi Rayon K.K. (2) "Synthetic pulp": Trade name "SWP" produced by Mitsui Zellerbach K.K. (3) "Tensile strength" and "Elongation" (at breaking): TENSILON (TOYO MEASURING INSTRUMENTS CO., LTD.; Length of test piece . . . . . 10 cm; Speed . . . . . 50 mm/min. (4) "MIT folding endurance": In accordance with Tappi Standard T511-Su-69 Load . . . . . 1 kg. (5) "Cantilever bending resistance": In accordance with JIS L1079A.
COMPARATIVE EXAMPLE
Example 1 was repeated except that the PVC latex was not heated, but the operation was carried out at 20° C. to obtain a flocculate having a particle size of 20μ-30μ, from which a non-woven fabric was produced. Properties of the resultant non-woven fabric are shown in Table 2. Such fabric could not practically be used.
TABLE 2______________________________________ Non-woven fabric______________________________________Blending of fibers NBKP 20 parts Rayon 80 partsPVC flocculate 30 partsBasis weight (g/m.sup.2) 46.3Tensile strength Dry 0.5(kg/15 mm width) Wet 0.1Elongation (%) Dry 8.3 Wet 7.6MIT folding endurance(load of 1 kg) --Cantilever bending 53resistance (mm)______________________________________
EXAMPLE 2
500 l of 5 weight % diluted liquid of Geon 351 (PVC latex prepared by Nihon Geon K. K. and having a MFT of 70° C.) was heated to 73° C. with stirring in such a manner that no bubbling occurred. To this liquid was added 17.5 kg of calcium chloride liquid having a concentration of 0.5 mol to obtain a flocculate having a particle size of 100μ-500μ.
This flocculate was stable even after allowed to stand for about 50 hours.
Said flocculate was added in an amount as shown in Table 3 to fiber slurries as shown in Table 3. Fibrous sheets were produced from the slurries by the known wet paper making and the resultant sheets were dried. Properties of the sheets are shown in Table 3. That is, they had a high dry and wet strengths and had no resin specks on the surface. Furthermore, no troubles occurred in paper making.
Since the fibers used in sample B in Table 3 were heat resistant fibers (Normex) and flameproofing fibers (Kynol) and the latex used was also excellent in fire retardancy, the resultant sheet had markedly excellent flameproofness.
TABLE 3______________________________________ A B______________________________________Blending of fibers NBKP 20 parts Kynol 70 parts Rayon 80 parts Normex 30 partsPVC flocculate 30 parts 30 partsBasis weight (g/m.sup.2) 49.6 97.4Tensile strength Dry 1.8 4.7(kg/15 mm width) Wet 0.8 3.2 Dry 13.0 6.9Elongation (%) Wet 25.0 5.3MIT folding enduranceresistance (times) (load of1 kg) 7,000 1,000Cantilever bendingresistance (mm) 118 156 After-flame time 0 (second)Verticaltest After-glow time 0flammability (second)test Char length 3 (cm)______________________________________ (Notes):- (1) Kynol: Flameproofing fibers produced by Nihon Kynol K.K. (Phenol resi fibers, 2 deniers and 10 mm in (2) Nomex: Heat resistant fibers produced by Du Pont de Nemours (aromatic polyamide fibers, 2 deniers and 6 mm in (3) Vertical flammability test: In accordance with JIS L1091-73R, A4 method
EXAMPLE 3
500 l of 1 weight % diluted liquid of Saran Latex N (Polyvinylidene chloride-acrylate copolymer prepared by Asahi Dow K. K. and having a MFT of 60° C.) was heated to 65° C. with stirring in such a manner that no bubbling occurred. To this liquid was added 4.1 kg of 2 weight % aqueous solution of Polyfix 201 to obtain a homogeneous flocculate dispersion having a particle size of 100μ-500μ, which was stable even after allowed to stand for about 50 hours under stirring. Separately, a fiber slurry was prepared by dispersing Kynol fibers.
To this fiber slurry was added said flocculate in an amount of 30% by weight of the fibers and then a fibrous sheet was produced therefrom by paper making and dried.
Properties of the resultant sheet were nearly the same as those of sample B in Example 2, namely, the sheet was excellent in dry and wet strength and had the excellent flameproofness.
No troubles occurred in the paper making. Furthermore, there were no resin specks on the sheet.
EXAMPLE 4
500 l of 2 weight % diluted liquid of a mixed latex of Geon 351 and Saran N (1:1 in solid matter) was heated to 75° C. with stirring in such a manner that no bubbling occurred. To this liquid was added 14 kg of 1.25 weight % aqueous solution of Polymin SN (polyethyleneimine cationic polymer prepared by BASF Dyes & Chemicals, LTD.) to obtain homogeneous flocculate having a particle size of 200μ-500μ. This flocculate was stable even after allowed to stand for about 50 hours under stirring. Then, a slurry having the same fiber blend as sample A in Example 2 was prepared. To this slurry was added said flocculate in an amount of 30% by weight of the fibers. A fibrous sheet was produced from said slurry by paper making and dried.
The resultant sheet had the satisfactory strength similar to that of non-woven fabric A in Example 2.
No troubles occurred in the paper making and there were no resin specks on the sheet. | A fibrous sheet having a high strength and water resistance and having no resin specks on the surface can be produced by producing a sheet from a fiber slury by the known paper making process, to said fiber slurry being added a flocculate of chlorinated polymer latices which has a particle size of 100μ-500 μ and is prepared by heating said chlorinated polymer latices to a temperature of at least their minimum film-forming temperature and then adding a water soluble cationic polymer or a polyvalent metal salt with stirring. Examples of said chlorinated polymer latices are anionic polyvinyl chloride latex, polyvinylidene chloride latex or the combination thereof. | 3 |
This application claims the benefit of U.S. Provisional Application No. 60/007,155, filed Nov. 1, 1995 and incorporates herein the disclosure of that application in its entirety.
FIELD OF THE INVENTION
The present invention relates generally to systems and methods for treating obstructive sleep apnea using an adaptive control system for adjusting and positioning a mandibular positioning device.
BACKGROUND OF THE INVENTION
Obstructive sleep apnea (OSA) is a common disorder which produces considerable morbidity and mortality. The disorder arises during sleep when the victim undergoes repeated cessation of breathing. This cessation results from an obstruction of the throat air passage (pharynx) due to severe narrowing or a collapse of the throat air passage. Repeated cessation of breathing reduces blood oxygen and disturbs sleep. Reduction in blood oxygen can cause hypertension, heart attacks and strokes. Additionally, sleep disturbances can produce excessive daytime sleepiness, headache, depression, irritability and cognitive impairments.
Medical research over the past decade has produced a standard approach to obstructive sleep apnea therapy, known as nasal continuous positive airway pressure (CPAP). In this therapeutic approach, a patient's nose is covered with a mask that forms a pressure seal with the surrounding face. While the patient sleeps, the mask is pressurized to a level that distends the collapsible throat air passage, thereby preventing obstruction.
This therapeutic approach provides two significant advantages: it is uniformly effective and it is entirely benign. A major disadvantage of this approach is that the patient must remain overnight in a hospital sleep center to undergo a full night polysomnography study with the pressure mask in place to determine the therapeutic level of pressure. A further disadvantage of this approach is that the pressure delivered to the patient during the polysomnography study is constant and fixed at the prescribed level, even though the patient's requirements may vary throughout the night and from night-to-night.
The overnight study presents a potential bottleneck to treating a high volume of patients with obstructive sleep apnea because it typically requires two full night polysomnographic studies for each new patient: one to establish the diagnosis (diagnostic-polysomnogram) and another to establish the aforementioned therapeutically optimal pressure (therapeutic-polysomnogram). The therapeutic polysomnographic study is necessary to determine the minimum level of pressure required to produce a patent pharyngeal airway (i.e., to determine the necessary therapeutic pressure required for properly treating the patient). These studies, performed in a specialized hospital sleep center, allow a specialist to specify the pressure to be used when prescribing nasal CPAP therapy. For this reason, the therapy cannot be prescribed by an internist or general practitioner.
Due to the requirement of two night polysomnographic studies, hospital sleep centers are crowded even though only a small percentage of obstructive sleep apnea victims are presently being treated. Further, the significant cost of the overnight polysomnographic study by a hospital sleep center represents a significant obstacle to diagnosing and treating the large population of sleep apneics. The backlog of undiagnosed and untreated obstructive sleep apnea patients thus represents a substantial public health problem.
To address the foregoing drawbacks of existing approaches to diagnosis and treatment of obstructive sleep apnea, recent commercial technology provides overnight, unattended monitoring of breathing in the patient's home. Such unattended monitoring generally permits the physician to diagnose obstructive sleep apnea without requiring a diagnostic overnight study in the hospital sleep center. However, a hospital sleep center is still required for establishing the therapeutically optimal pressure of nasal CPAP in each patient. Accordingly, medical practitioners have been slow to use the new monitoring technology for diagnostic purposes since the patient must, in any case, be referred to a sleep center for a full night therapeutic polysomnographic study.
While there is a continuing need for CPAP technologies, clinical studies and general clinical experience indicate that nasal CPAP is not always an effective treatment for many patients with obstructive sleep apnea, particularly those with symptoms of mild to moderate severity.
Various surgical approaches have been employed to correct the structural abnormality of the pharyngeal airway. Excluding massive reconstruction of the mandibular, maxilla and/or tongue, the only widely employed surgery has been uvulopalatopharyngoplasty (UPPP). However, results with UPPP are disappointing unless patients are selected by pharyngeal endoscopy during sleep and, even then, the long term benefits are questionable. Laser-assisted uvulopalatoplasty (LAUP) is a new approach which has been recommended for obstructive sleep apnea. No studies have reported the effectiveness of LAUP in the treatment of obstructive sleep apnea, but there is little reason to anticipate that it will be more effective than UPPP although it may be more convenient, less expensive and may prove to be a useful adjunct therapy to be used in combination with mandibular positioner (MP) therapy for patients in which MP therapy does not eliminate apneas and hypopneas.
Stationary oral appliances which draw the tongue forward have been used in the treatment of snoring. In addition, some recent studies suggest that a fixed oral appliance (i.e., mandibular positioner) which holds the lower jaw (i.e., mandible) of the patient forward as the patient sleeps is effective in treating obstructive sleep apnea, especially mild obstructive sleep apnea. Studies have shown that ventral displacement of the mandible enlarges the pharyngeal airway and acts to prevent its closure. Conventional mandibular positioners are constructed by a dentist or orthodontist at a fixed position for holding the mandible forward. The proper fixed position is determined through trial and error by having the patient try a series of mandibular positioning devices until the most effective one is found. Once the mandible displacement is set for the device, it remains stationary with no accommodation for variations in the obstructive sleep apnea, such as body position, sleep state, effects of drugs, and congestion of the patient.
An adjustable mandibular positioner, developed by Dr. A. Lowe, Head, Department of Orthodontics, University of British Columbia allows incremental adjustment of the ventral displacement of the mandible. This device is referred to as a screw adjustable mandibular positioner (SAMP), because its upper and lower full arch orthotics are connected by a manual screw device which is adjusted by the patient or dentist to set the magnitude of mandibular advancement. Thus, the patient or dentist can progressively advance the mandible with the SAMP over a period of weeks to months so that mandibular muscles and ligaments can adjust, thereby allowing greater ventral displacement and minimizing side effects.
Accordingly, it would be desirable to render the therapy of obstructive sleep apnea more practical and convenient. To achieve this end, a method and system for automatically establishing the desired mandible advancement for a patient during changing sleep conditions is needed. More particularly, a system is needed with an adaptively controlled mandibular positioner that automatically adjusts to a patient's needs throughout the night and from night to night.
SUMMARY OF INVENTION
The present invention is therefore directed to providing a practical, convenient and cost-effective system for adaptively treating obstructive sleep apnea with an automatic, self-adjusting mandibular positioner. Further, the invention is directed to portable systems and methods for automatically and continuously regulating the position of the patient's mandible to an optimal position during obstructive sleep apnea treatment during long term nightly use at home. The present invention utilizes an automatic mandibular positioning system having adaptive control software which uses readily measurable, robust feedback variables to automatically adjust a mandibular positioner for obstructive sleep apnea treatment. Obstructive sleep apnea therapy is implemented in the present invention by automatically applying an appropriate mandible advancement to a patient. The mandible position is continuously reevaluated and optimized throughout the night. The optimal position varies with body position, congestion, stage of sleep, and whether any deleterious substances, such as alcohol or sleeping medicine, have been ingested.
The present invention is a portable adaptive control system which continually searches for the optimal minimum mandible advancement required to adequately distend a patient's nasal pharyngeal airway. By rendering the system portable, a large percentage of obstructive sleep apnea victims can be cost-effectively treated in their homes, thus reducing the overcrowding in expensive hospital sleep centers. Optimal minimum advancement is used because greater advancements increase the likelihood of side effects (e.g., sore muscles), and reduce the likelihood of patient compliance. A patient's compliance in regularly using the system is a significant concern inasmuch as the system is a portable device used at the patient's home without the supervision of a hospital sleep center specialist.
In one aspect of the present invention there is provided a method for adaptively controlling mandibular displacement for the treatment of obstructive sleep apnea in a patient by (a) monitoring the patient for evidence of obstruction of the patient's airway, (b) displacing the patient's mandible if evidence of obstruction is detected and (c) repeating steps (a) and (b) until evidence of obstruction is eliminated or reduced below a predetermined value.
In another aspect of the present invention there is provided a method for adaptively controlling mandibular displacement for the treatment of obstructive sleep apnea in a patient by detecting obstruction in a patient's upper airway system, identifying periods of inspiration and expiration for the patient, and incrementally adjusting a patient's mandible in response to the obstruction information detected during the period of inspiration.
In yet another aspect of the present invention there is provided a system for adaptively controlling mandibular displacement for the treatment of obstructive sleep apnea in a patient having an adjustable mandibular displacement device, a unit which detects evidence of obstruction of the patient's airway, and a control system for adaptively controlling the adjustable mandibular displacement device in response to the detecting unit.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments when read in conjunction with the accompanying drawings, wherein like elements have been designated by like numerals and wherein:
FIG. 1 is a diagrammatic representation of an adaptive mandibular positioner system; and
FIG. 2 is a conceptual diagram of an operator of the adaptive control system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is an auto-mandibular positioning (i.e., auto-MP) system for adaptively providing a mandible position effective in treating obstructive sleep apnea. The auto-MP system is an automatic, self-adjusting mandibular positioner and controller which performs detection, analysis, and decision-making functions.
With reference to FIG. 1, there is shown an adaptive mandibular positioner system 20 in accordance with one embodiment of the present invention. In this embodiment, adjustable mandibular displacement device 22 comprises a lower dental appliance 24 attached to mounting bracket 26 having a linear actuator 28 mounted thereon. Linear actuator 28 is in contact with or attached to upper dental appliance 30. The upper and lower dental appliances are free to slide relative to each other such that when the linear actuator 28 exerts force on the upper dental appliance (which can not move because the patient's upper teeth are attached to the maxilla which is fixed to the skull) the linear actuator 28, mounting bracket 26 and lower dental appliance 24 are displaced in a direction away from the patient. As a result, the lower dental appliance 24 draws the patient's mandible forward (i.e., ventrally) to open the patient's upper airway. In the illustrated embodiment, the actuator 28 and mounting bracket 26 displace the mandible in a linear manner, however it is within the scope of the invention that the actuator and mounting bracket be configured to displace the mandible along the patient's naturally occurring protruding path. For example, the path may be an arcuate path forward and downward, or forward and upward. Likewise, the patient's mandible may angle slightly to one side or the other as it protrudes.
In one embodiment, the upper and lower dental appliances are formed by filling an upper dental tray (which can be a partial or full arch) and a full arch lower dental tray, which can be custom fitted to a particular patient or be in standard sizes, for example small, medium and large, with a silastic impression material (e.g., PolyFil® TransBite available from SciCan® Medtech AG, Cham, Switzerland). Inserting the upper and lower dental trays in the patient's mouth and having the patient bite down until the molding material sets. In other embodiments, the upper and lower dental appliances can be formed with conventional materials such as heat deformable plastics which are placed in heated water or other suitable heating device before being inserted in the patient's mouth.
As illustrated in FIG. 1, the linear actuator 28 is driven by an actuator controller 32 having an external power source 34 (or an internal power source). Actuator controller 32 is controlled by adaptive control unit 36. The adaptive control unit in the illustrated embodiment is a personal computer but a special unit can be manufactured and used as well. Adaptive control unit 36 is usually located in an area near the patient and the mandibular positioning device 22. Attached to the adaptive control unit 36 is a recording and display device 38 (e.g., a polygraph paper chart and/or a magnetic recording device with a display) which receives inputs from the adaptive control unit 36 and from patient monitoring devices 40 (e.g., oxygen saturation, airflow, snoring sound) through the unit 36 as will be described in more detail below. The linear actuator 28 can be any of a variety of actuators as will be recognized by one of ordinary skill in the art and be within the scope of the present invention. Two of such actuators are described below. The linear actuator is capable of a maximum displacement of 25 millimeters, but for most patient's the maximum displacement is 16 millimeters.
In one such embodiment, the actuator system is comprised of a stepper motor controller connected to a personal computer for driving a stepper motor connected to a micrometer which moves a first hydraulic piston. The first hydraulic piston is in fluid communication through a 0.5 millimeter inside diameter, 2 millimeter outside diameter hydraulic line with a second hydraulic piston and cylinder mounted on the mounting bracket 26. The second hydraulic piston has a pressure plate for contacting or attaching to the upper dental appliance. When the stepper motor and micrometer move the first hydraulic piston, the pressure in the hydraulic line causes the second hydraulic piston to exert force on the patient's upper teeth through the pressure plate in contact with the upper dental appliance and protrude the patient's mandible with the lower dental appliance. When the pressure in the first hydraulic piston is reduced, the natural elastic nature of the patient's muscles in the jaw cause the patient's mandible to retrude while biasing members attached between the second hydraulic piston and the pressure plate cause the second hydraulic piston to retract. In this embodiment, moving the stepping motor 1 millimeter results in 1 millimeter of displacement of the patient's mandible. Optionally, a pressure transducer can be in fluid communication with the hydraulic line to measure the amount of force being exerted on the patient's muscles and ligaments to prevent excessive force that may cause patient discomfort or arousal. Preferably, the second piston and cylinder and mounting bracket are made of aluminum or similar lightweight material so that the patient is not aware of external forces applied to the patient's teeth.
In another embodiment of the actuator system, the hydraulic system just described is replaced with a small stepper motor (e.g., model no. 20841-05 available from Haydon Switch and Instrument, Inc. in Waterbury, Conn.) mounted on the mounting bracket 26. The actuator controller 32 is a model 40105 Bipolar Chopper Driver available from Haydon Switch and Instrument, Inc. in Waterbury, Conn. The stepper motor mounted on the mounting bracket 26 has a screw shaft extending through the center thereof with a pressure plate at the distal end of the shaft for contacting or attaching to the upper dental appliance. When the actuator controller 32 receives a protrude signal from the adaptive control unit 36, the actuator controller sends a signal to the stepper motor which rotates the screw shaft. The screw shaft extends toward the upper dental appliance to exert force on the patient's upper teeth through the pressure plate in contact with the upper dental appliance and protrude the patient's mandible with the lower dental appliance. When the actuator controller 32 receives a retract signal from the adaptive control unit, the actuator controller sends a signal to the stepper motor which rotates the screw shaft in the opposite direction. The screw shaft retracts the pressure plate and the natural elastic nature of the patient's muscles in the jaw cause the patient's mandible to retrude. In this embodiment, the adaptive control unit sends three signals to the actuator controller. One signal tells the stepping motor to turn on or off, another signal tells the stepping motor the direction to move (i.e., clockwise or counterclockwise), and another signal tells the stepping motor the number of steps to move (e.g., 1 step=15 degrees of shaft rotation=1/40 millimeter of linear displacement).
Attached to the strut 42 of the linear actuator 28 are two cannulae 41 with openings positioned to correspond to the patient's nares (not shown) (FIG. 1). These cannulae are connected to a pressure transducer (e.g., Oyster model 723 from Schaller) for recording an index of respiratory airflow. The kinetic energy of the expired air increases the pressure in the cannula, thereby providing a direct index of expiratory airflow rate. Conversely, during inspiration, the pressure in the cannula decreases providing an index of inspiratory airflow. Snoring is sensed by a piezo-electric transducer applied to the neck over the trachea, typically using a contact microphone. Alternatively, the piezo-electric transducer can be implanted in the upper dental appliance. The signal from the transducer is digitized and integrated. Peak snoring and duration of snoring are detected. Snoring is deemed "detected" when a sound of 200 milliseconds duration is detected for 2 consecutive breaths. Arterial oxygen saturation is detected by a pulse oximeter attached to the ear lobe, the finger or the lip. For the lip, the light emitter 44 is attached to the ventral aspect of the upper dental appliance and the sensor 46 is attached to the strut of the upper dental appliance.
Feedback variables which provide the most useful information for the adaptive control system include: snoring sound, oxygen saturation and nasal airflow. These are selected because they are robust signals and are easily incorporated into the auto MP nightly use.
As snoring is caused by vibration of the soft palate, it is therefore indicative of an unstable airway and is a warning signal of the imminence of upper airway obstruction in patients that suffer obstructive sleep apnea. Snoring is itself undesirable not only as it is a disturbance to others but it is strongly believed to be connected with hypertension. If the resultant increase in mandibular protrusion is sufficient to completely stabilize the airway, snoring will cease. If a further snoring sound is detected, the protruded distance is again incrementally increased. This process is repeated until the upper airway is stabilized and snoring ceases. Hence, the occurrence of obstructive apnea can be eliminated by application of minimum mandible displacement at the time of use.
The adaptive control unit gradually decreases the mandible displacement if an extended period of unobstructed breathing occurs in order to ensure that the degree of mandible displacement is maintained at a level as low as practicable to prevent the onset of apnea. If, however, evidence of obstruction is detected by the adaptive control unit, the system will again act to incrementally increase the protruded distance of the mandible.
In use, a patient using adaptive mandibular positioner system 20 may connect himself to the apparatus and go to sleep. The mandible displacement is initially at a minimum displacement, for example, the patient's natural mandible position at rest or slightly protruded so as not to cause discomfort that prevents sleep. Not until some time after going to sleep and the patient's body relaxes will the airway start to become unstable and the patient will begin to snore or experience some obstruction of the airway. The patient inputs 40 will detect the snore or obstruction and send a signal to adaptive control unit 36. The adaptive control unit will then respond to the obstruction via the actuator controller 32 to increase the protruded distance of the patient's mandible. The displacement can be increased relatively rapidly, if the patient's condition so requires but care is taken to not arouse the patient.
If in the early stages of sleep some lesser mandible displacement will suffice, system 20 will not increase the displacement until needed, that is, unless the airway becomes unstable and evidence of obstruction commences, no increase in displacement is made. By continuously decreasing the displacement (unless the mandible is already in the natural position) in the absence of evidence of obstruction, the displacement is never substantially greater than that required to prevent apnea.
The adaptive mandibular positioner system 20 provides a system which adjusts mandibular displacement according to variations in a patient's breathing requirements throughout an entire sleep period. Further, system 20 will likewise accommodate variable displacement requirements owing to general improvements or deteriorations in a patient's general physical condition as may occur over an extended period of time.
Patient inputs 40 preferably comprise at least one of an oxygen saturation monitor, a sound monitor, and an airflow monitor which continuously detects changes in the patient's breathing patterns. Concurrently, the patient inputs unit 40 generates output signals corresponding to the continuously detected signals and transmits these signals to adaptive control unit 36.
Depending upon the characteristics of the patient inputs signal, the adaptive control unit may generate a command signal to either increase or decrease the mandibular displacement. The adjustable mandibular positioner 22, patient inputs 40 and adaptive control unit 36 thus comprise a feedback circuit or system capable of continuously and automatically controlling the displacement of the patient's mandible responsive to the patient's respiratory requirements as dictated by the patient's breathing patterns.
Obstruction of the upper airway is manifested by high upper airway resistance, hypopneas or apneas. High upper airway resistance is detected when snoring is present, peak flow is reduced and/or the profile of inspiratory flow is flat. Hypopneas are signified by snoring, reduction of peak airflow, flat inspiratory flow trajectory and a decrease in oxygen saturation. Apneas are manifested by absence of snoring and airflow followed by oxygen desaturation in the range of 5 to 10 seconds.
When the patient inputs unit 40 detects breathing patterns indicative of obstructed breathing, it transmits signals corresponding to this condition to the adaptive control unit 36. The adaptive control unit 36 then causes the mandibular positioner 22 to increase the protrusion of the mandible incrementally (e.g., in the range of 0.25 to 2 millimeters, preferably in the range of 0.5 to 1 millimeter) which opens the patients airway until obstructed breathing is no longer detected. The system also includes means such as appropriate logic programmed into the unit 36 whereby the displacement is gradually decreased if unobstructed breathing patterns are detected over a preselected period of time (e.g., in the range of 10 seconds to 4 minutes, preferably for 2 to 4 minutes). This feature serves to provide the patient with a ventral displacement of the mandible minimally sufficient to maintain airway patency during unobstructed breathing, thus enhancing patient comfort and therapy compliance.
Several embodiments for adaptive control of the auto MP are available. One embodiment utilizes a predetermined displacement step in position of the mandible during the expiratory phase. Snoring (if present) and peak airflow during a first test set (e.g., in the range of 1 breath to 10 breaths) after the displacement step are compared to the mean of the preceding breaths (e.g., in the range of 2 to 10 breaths, preferably 3 to 5 breaths). In addition, measures of the shape of the inspiratory flow profile (i.e., flatness and roundness) are calculated and compared to preceding values.
Another embodiment utilizes a strategy of incrementing the mandibular position by 1 millimeter when snoring and/or desaturations are present. After each increment, the feedback variables will be monitored for a predetermined period (e.g., in the range of 10 seconds to 4 minutes). Our studies indicate that often snoring will disappear shortly after the increment in mandibular position and then reappear. Accordingly, if snoring and desaturations reappear, the process will be continued until snoring reaches a minimum value and desaturations are eliminated, or the limits of extension are reached as indicated by pressure and displacement information.
In one embodiment, airflow is used to assess the respiratory and dynamic mechanical characteristics of a patient's pharyngeal airway (PA) during sleep and to adjust the therapeutic mandible advancement as required.
Respiratory airflow typically corresponds to patient breathing and has two sequential, tidal components: one caused by inhalation and another caused by exhalation. This tidal airflow is phasic and therefore allows the onset of inspiration and the onset of expiration to be identified. Because the onset and termination of inspiration are identifiable, parameters related to the shape of a time profile of inspiratory flow can also be determined. In a preferred embodiment, a degree of roundness and flatness of the inspiratory profile are determined as will be described later.
The measurement of airflow and subsequent determination of an inspiratory airflow profile are used to control the position of the patient's mandible in accordance with the present invention. When the degree of mandible displacement produces the maximal distention of the airway with the minimum displacement is abruptly reduced in sleeping patients suffering from obstructive sleep apnea, the pharynx is observed to collapse and the pharyngeal resistance increases accordingly. This change in upper airway resistance induces changes in peak inspiratory airflow and profile shape with little change in airway pressure below the obstruction. Accordingly, changes in airflow resistance can be inferred from changes in the inspiratory airflow.
Further retrusion of the mandible leads to progressive collapse of the pharyngeal airway which severely reduces inspiratory airflow and causes flow limitations (i.e., increased airflow resistance). Similarly, progressive increases in the degree of mandible protrusion leads to smaller decrements in airflow resistance as the pharynx widens and reaches the limits of its distensibility. The collapsible behavior of the pharyngeal airway in response to progressive reductions in the degree of mandible displacement provides a framework for determining an optimal therapeutic mandible displacement in accordance with the present invention.
Accordingly, a preferred embodiment includes an adaptive control system for displacing the patient's mandible in response to detected airflow. This mandible displacement is adaptively adjusted to apply an optimal minimum therapeutic displacement.
During a testing mode of the auto-MP system, the displacement of the patient's mandible is changed frequently. The position of the mandible is changed by sending a signal from the computer 36 to controller 32 which sends the proper signal to actuator 28.
Generally speaking, the adaptive control system generates an optimal desired (i.e., command) displacement by detecting airflow data over a predetermined period of time, identifying periods of inspiration and expiration, and extracting information or features from the airflow data. Using this information, the adaptive control system identifies a critical displacement (D crit ) at which a significant obstruction occurs during inspiration. More particularly, D crit corresponds to a lower limit of mandibular displacement associated with a significant decrease in peak inspiratory airflow and/or significant (i.e., critical) airflow limitation. After determining D crit , the adaptive control system identifies an optimum (i.e., minimum) effective mandible position (D opt ) for eliminating the obstruction during inspiration.
The adaptive control system identifies D crit and decides upon D opt using a series of test displacements in the mandible position. Results of the tests are evaluated by examining inspiratory airflow. D opt is continuously updated during testing periods which are initiated throughout the night to account for changes in the patient's sleep stages and sleeping position.
Because a testing period is used to update D opt , the adaptive control system also decides when to test the pharyngeal airway, and when to continue or to stop testing. Further, the adaptive control system (1) manages overall operation to optimize its own performance, and (2) monitors potential airflow measurement errors to accurately measure upper airway performance as will be described below.
Airflow changes and airflow profile changes in the upper airway system have been determined to be directly related to intra-pharyngeal pressure. By determining upper and lower limits of pharyngeal resistance from changes in airflow during a testing period, D opt can be determined for any patient at any time. Accordingly, the adaptive control system searches for D opt between a lower airflow limitation (D crit ) and an upper limit (full distention of the airway).
Operating within these relative limits ensures reliable assessment of the pharyngeal airway and an accurate determination of D opt . Because airflow varies widely among patients and, for any particular patient, varies with sleep stage, D opt can not be determined by comparing airflow measurements with ideal or predicted standards.
Generally speaking the adaptive control system conceptually includes four basic components for performing the aforementioned testing and non-testing control. As shown in FIG. 2, these four basic components are an operator, a feature extractor, a testing protocol, and long term memory.
a. Operator
The adaptive control operator is an overseer that has access to information of the feature extractor at all times, decides when and when not to enter the testing protocol, controls the flow of information to and from longterm memory, and maintains optimal performance and reliability. Decisions are made by the operator to ensure that the adaptive control system operates within predetermined operating limits so that accuracy is maintained.
The normal operating limits for the adaptive control system are based on rules of operation. These rules of operation ensure that so called performance indices are within predetermined physiological ranges, and that a respiratory phase threshold detection mechanism system is functioning efficiently. Further, these rules are used by the adaptive control system to make decisions, such as when to exit a testing period or when to return to a testing period.
To ensure operation within predetermined physiological limits, the rules are designed to have the adaptive control system operate whenever there is (1) a low to moderate level of variation in respiratory features, (2) no hypoventilation and (3) no apnea.
For purposes of the present discussion of preferred embodiments, a large variation in the respiratory features is defined as a variation coefficient value of 0.3 or more for four or more specified features (e.g., time of inspiration (T i ), total time of breath (T tot ), mean inspiratory airflow (V m ), peak inspiratory airflow (V p ), and Roundness) for a set of 2 to 40 breaths depending on whether it is in a testing or a non-testing mode, respectively; hypoventilation is defined as five (5) consecutive breaths with V m less than 40 percent of the predicted awake supine V m ; and apnea is defined as a 10 seconds duration of no change in respiratory phase.
Satisfaction of these rules is the criteria used by the adaptive controller in deciding whether or not to enter a testing mode. If these rules are not satisfied during a non-testing period, either a subsequent testing period is delayed or the adjustable mandibular positioner is adjusted or both. If these rules are not satisfied during a testing period, the testing ceases and there is a return to the previous D opt , or to a displacement position previously set by an outside source, whatever is higher.
As mentioned above, the operator is an overseer which decides when to enter a testing mode. Decisions made by the adaptive control system (e.g., when to test and when to discontinue testing) are based on dynamic characteristics, or performance indices, of the pharyngeal airway during the non-testing and testing periods. During non-testing and testing periods, the adaptive control system continuously monitors breathing variations, hypoventilation, and apnea.
(1) Non-Testing Mode Periods
The adaptive control system operates in one of two basic modes: a non-testing mode (n-TM) and a testing mode (TM). Throughout the testing and non-testing modes, characteristics of the upper airway are continuously detected and evaluated by the feature extractor. In the non-testing mode (i.e., non-testing period), results generated by the feature extractor are used to determine if and when to delay testing, to optimize rules of operation, and to identify deteriorating changes in airflow.
While in the non-testing mode, the auto-MP system monitors the information from the feature extractor. This information is used to determine the presence of large variations in breathing frequency, hypoventilation, or apnea. Testing under these conditions could lead to erroneous results. Therefore entering into the testing mode may be delayed.
(2) Testing Mode Periods
When the adaptive control operator decides to redetermine D crit and D opt , then the testing mode is executed in accordance with the testing protocol. As in a non-testing period, the operator has continuous access to the information from the feature extractor during a testing period to determine if it should continue to test for D crit and D opt .
When the auto-MP system enters the testing mode, a specific testing protocol of incremental mandible displacements is followed. Prior to identifying D opt , the testing protocol is only interrupted if a large breathing variation, an apnea or hypoventilation is detected. The results from the non-testing mode and the testing mode are retained in the longterm memory.
b. Feature Extractor
The feature extractor (FE) is the center for continuous acquisition and analysis of data. For example, the feature extractor generates performance indices in response to respiratory airflow data. These performance indices are a measure of the pharyngeal airway's dynamic state and are used by the operator for decision making in both the testing and non-testing modes. In alternate embodiments, additional signals (e.g., monitoring signals related to oxygen saturation and sound) can be input to the feature extractor to assist in the continuous sensing of dynamic characteristics of the pharyngeal airway.
The feature extractor has two basic functional modules: a data acquisition module and a respiratory cycle analysis (RCA) module. Data acquisition of the input signals (e.g., airflow) occurs via the patient inputs 40 every 8 msec. These values are then passed into an RCA module where eight consecutive values are averaged to produce a single low pass filtered average value every 64 msec. Each 64 msec average value is then continuously analyzed in the RCA module for phase of respiration, apnea, and breath features.
Performance indices generated by the RCA module are updated continuously as follows, where the asterisks indicate a real time occurrence of an update for the feature listed:
______________________________________ During During Inspiration Expiration______________________________________Respiratory * * (continually)phaseEnd of Breath * (end of expiration)RCA Abnormalities * *Apnea * *BreathFeatures:T.sub.i * (time of inspiration)T.sub.e * (time of expiration)T.sub.tot * (total time of breath)Vol.sub.i * (inspiratory volume)Vol.sub.e * (expiratory volume)V.sub.m * (mean inspiratory airflow)V.sub.p * (peak inspiratory airflow)Flatness * (measure of inspiratory flatness)Roundness * (measure of inspiratory roundness)______________________________________
As mentioned previously, an optimum mandibular position is determined by evaluating the effects of incremental protruded steps on inspiratory airflow. Accordingly, the RCA module is designed to continuously report breath changes in upper airway state (i.e., to identify respiratory phase and end of breath conditions based on extracted features). A breath is defined as an inspiratory period followed by an expiration period. Therefore, an end of breath condition is updated at the end of expiration.
When the RCA module detects a problem, then an RCA abnormalities condition is set. For example, the RCA module is designed to continuously report detection of apneas based on extracted features.
The breath features listed above are the dynamic physiological characteristics of the pharyngeal airway. Their variation, especially in combination, are excellent measures of the pharyngeal airway behavior. Values of T i , T e , T tot , Vol i , Vol e , V m and V p (defmed in the above table) are physiologically self explanatory breath features. Flatness and roundness values are breath features which are developed as measures of inspiratory airflow. The flatness and roundness values are used in accordance with preferred embodiments to identify pharyngeal airway behavior.
For purposes of the present discussion, flatness is defined as the relative deviation of the observed airflow from the mean airflow. In a preferred embodiment, individual values of airflow are obtained between 40% and 80% of the inspiration period. The mean value is calculated and subtracted from the individual values of inspiration flow. These individual differences are squared and divided by the total number of observations minus one. The square root of this product is used to determine a relative variation.
The relative variation is divided by the V m to give a relative deviation or a coefficient of variation for that breath. This measure of airflow therefore represents a measure of flatness over the mid-range of inspiration. A relatively low value is used to indicate that inspiration airflow during mid-inspiration is relatively constant. The common cause of this is flow-limitation secondary to pharyngeal collapse. Thus, a low value indicates the need for greater mandible protrusion.
For purposes of the present discussion, the roundness feature supplies information regarding the similarity between the normalized inspiration flow profile and a sine wave normalized for observed inspiration time and for observed peak flow. The airflow predicted from the sine wave, Vsine, is calculated from the following normalized sine wave equation:
Vsine=Vpeak*sine(F*π)
where Vpeak is observed peak flow and F equals the fraction of inspiratory time elapsed. This equation for predicting sequential airflow measurements is used when the ratio of peak flow to T i is less than 1.1 and greater than 0.45. For values of the ratio greater than 1.1 the peak is estimated by multiplying T i by 1.1, and for values below 0.45 the peak is estimated by multiplying T i by 0.45.
The differences between consecutive values of observed inspiratory airflow and that calculated from the sine wave equation value are squared and summed, and then divided by the total number of points. The square root of this product is then divided by the mean value of airflow for that inspiration to give a normalized value for that breath.
Accordingly, the roundness index provides an estimate of the degree to which the inspiration airflow profile resembles a sine wave. As flow limitation occurs or as the airflow signal becomes less sinusoidal, the roundness feature becomes larger. This indicates an increase in upper airway resistance and suggests that the protrusion of the mandible may not be adequate. V p and flatness are measures of flow limitation and roundness is a measure of increasing upper airway resistance.
To update the performance indices and other information presented in the above chart, the RCA module includes a respiratory phase threshold detection mechanism (TDM). The threshold detection mechanism detects the inspiration and expiratory phase changes in airflow. The accuracy of the feature extraction is very dependent upon accurate detection of the start of inspiration. In accordance with preferred embodiments, the start of inspiration is ascertained solely from airflow.
Basic assumptions in the threshold detection mechanism are that inspiration and expiratory volumes are approximately equal. Two factors affect the volumes causing them to be unequal. The volume of oxygen consumed per unit time is normally greater than the volume of carbon dioxide that is produced by the body. Further, breath-to-breath variation in tidal volume and timing during sleep, as well as arousal which alters alveolar ventilation and exact expiration volume, can result in a variation between inspiration and expiratory volumes.
Normally the inspiration tidal volume is 4% greater than the expiratory tidal volume. Over a 30 second period of quiet breathing, all variations can be approximately averaged out of this ratio. Therefore, a resultant average respiratory flow can be used as a basis to estimate the beginning of inspiration and to approximate non-respiratory flow. The actual start of inspiration flow can be detected when the airflow signal crosses a no-flow value. This is because the actual zero respiratory flow corresponds to the zero flow value.
c. Testing Protocol
During testing periods, the adaptive control system first reduces the protruded distance of the mandible and determines D crit . This constitutes a characteristic lower limit for the ventral displacement of the mandible for a given state of the patient's pharyngeal airway (e.g., sleep stage, position, and so forth). Having established this lower limit, the optimum displacement value D opt is determined by progressively increasing the protruded distance. The increases in peak inspiration flow and changes in the shape of the inspiration airflow profile are recorded and used to identify D opt .
The determination of D crit during a testing period is termed the D crit search. The subsequent determination of D opt during a testing period is termed the D opt search. Each search consists of a progressive series of incremental changes in mandible displacement (i.e., step decreases for D crit and step increases for D opt ).
A test for D crit during a D crit search is repeated until predetermined decision criteria have been met (i.e., changes in peak inspiration airflow and/or profile shape features detected by the feature extractor exceed predetermined decision criteria) or until a limit to the D crit search set by the D crit scan is encountered. Each D crit test is initiated with a pre-test period which is followed by a single breath test period and a five breath post-test period. However, when the decision criteria for the D crit search have been satisfied during the single breath test, there is no post-test period.
The D opt search is a series of step increases in displacement (e.g., 0.5 to 2 millimeters) which is initiated after D crit has been determined. The search for D opt involves finding the mandible position at which the peak flow and the flow profile do not improve after a predetermined step increase in displacement. Thus, the minimum effective mandible protruded distance represents that distance at which there is no improvement in the flow profile after a worsening in the flow profile.
Each D opt test is initiated with a pre-test similar to that of a D crit pre-test. A short test period and a longer post-test period follow the pre-test. A D opt search continues provided normal rules of operation are met until predetermined decision criteria for a minimum effective mandible position have been met.
In any test, if the decision criteria for a flow alone condition was exceeded (D crit ) or not exceeded (D opt ), then the test is repeated. A flow alone condition corresponds to a relatively large change in peak airflow with little or no relative change in roundness and/or flatness. If an apnea, hypoventilation or respiratory variation error is detected during the testing, the testing mode is exited and the system goes directly to the mandible position of the previous non-testing period.
The decision criteria for D crit are considered to have been satisfied if a relative change in extracted features exceeds the predetermined decision criteria (DC) in any one of four ways: (1) difference between feature values extracted during a first breath test and currently established pre-test feature values exceed the DC; (2) difference between feature values extracted using an average of 4th and 5th breaths detected during the post-test (post-test average) and currently established pre-test feature values exceed the DC; (3) difference between feature values extracted during subsequent single test breaths and the initial pre-test feature values previously established during the initial pre-test exceed the DC; or (4) difference between feature values extracted during subsequent post-tests and feature values of the initial pre-test exceed the DC. The detection of D crit using the comparisons of (3) and (4) above is referred to herein as a trend test. While comparisons similar to (1) and (2) above are used to identify D opt , the trend test comparisons are used only to determine D crit .
More particularly, the trend test is used exclusively in the D crit search to detect a progressive decrease in the flow profile over the D crit search that may not show up during any one single breath test or post-test. As described above, the trend test uses the initial pre-test features (e.g., five breath average) as the template for subsequent comparisons during tests (3) and (4).
In an exemplary embodiment, a test is true during a D crit search if relative changes in the V p feature and the flatness feature or relative changes in the V P feature and the roundness feature have exceeded the DC. Similarly, during a D opt search, if relative changes in the V p feature and the flatness feature or relative changes in the V p feature and the roundness feature changes have not exceeded the DC, the test is true.
A search for D crit begins with the scan protocol. As mentioned above, an exemplary scan is an incremental step decrease in mandible displacement. This decrease is preceded by a predetermined period (e.g., 5 breaths). The average values from the features during the pre-step decrease of a scan are used as control values during the scan. If the comparison between the predetermined period average and the post step decrease during a scan is significant, the system records that the scan was significant and the post scan mandible position becomes the limiting position during the D crit search.
The search protocol begins with the search for D crit at the same mandible position as the preceding scan. The search protocol begins with a pre-test during which, for example, 5 breaths prior a step decrease are averaged and used as controls for comparisons during subsequent single breath tests and post-tests. Following the pre-test breaths, the protruded distance is decreased a predetermined incremental step and the subsequent inspiration breath features are collected.
If the breath features after the decrease did not exceed the DC set for this degree of displacement, then the mandible position is left unchanged and a post-test period begins, for example, consisting of 5 breaths. The fourth and fifth breaths of this post-test period are averaged (i.e., post-test average) and the average is tested to see if it exceeded the same DC of the single breath test. If the DC is exceeded in either the single breath test or the post-test average, then the mandible position is returned to the position set during the pre-test period and a D opt search is initiated. When the mandible is protruded during the D opt search, a slightly longer test period (e.g., in the range of 15 to 60 seconds, 5 to 20 breaths) is used.
If neither the single breath test nor the post-test average exceeded the DC, then another test is performed, in this case a D crit test. Accordingly, during a subsequent single breath test and post-test, a trend test will be used to compare extracted features with features of the initial pre-test average. These comparisons are performed in addition to comparisons of extracted features with the current pre-test average as discussed above.
In an exemplary embodiment, if a second cycle of a D crit search pre-test, single breath test, and post-test does not exceed the DC, or if the previous D crit scan was significant but the limiting distance was not reached, then the scan protocol is repeated at the previous search position. This basic scan-search combined protocol is repeated until the least displacement of the mandible is reached or until the comparisons exceed the test criteria. For example, if the initial scan was not significant and D crit has not been detected after two incremental decreases, another scan will be performed. In this scan, an additional decrease is introduced. The aforementioned D crit search is then repeated.
An exemplary search protocol for D opt is slightly different than the search used to identify D crit . A scan is not used in the testing protocol to identify D opt . Further, during a preferred D opt search, a pre-test series, for example, of 5 breaths, precedes an incremental increase in mandible displacement. Further, the trend tests used to identify D crit are not used to identify D opt . The D opt search protocol consists of, for example, 5 pre-test breaths, a step increase in displacement, and an optional post-test period (e.g., in the range of 15 to 60 seconds) if it was the first D opt test. This D opt protocol is repeated until no significant differences exist between V p and/or profile shape indices of the pre-test relative to the single breath test and the post-test.
d. Long Term Memory
The long term memory stores specific information for use by the physician or a sleep laboratory for diagnostic or for follow-up therapeutic applications. In addition to recording upper airway system characteristic features during system operation, stored information can be assembled to identify the patient's use of the auto-MP system at home or in diagnostic or therapeutic studies. This information can be used by the physician to assess the integrity of results obtained during home or lab use of the system.
It will be appreciated by those of ordinary skill in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential character thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalents thereof are intended to be embraced therein. | The present invention relates to systems and methods for automatically and continuously regulating the amount of mandibular displacement to an optimal value during obstructive sleep apnea treatment. Obstructive sleep apnea therapy is implemented by a device which automatically reevaluates an applied mandibular displacement and continually searches for a minimum displacement required to adequately distend a patient's pharyngeal airway. The minimum optimal displacement varies with body position, stage of sleep throughout the night, the patient's body weight, and whether alcohol or sleeping medicine has been ingested. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to a method of knitting a thick fabric less in elasticity which is knitted by a flat knitting machine.
It is known in the art to employ Milano rib knitting to knit a thick fabric for use in the collar, front or the like of suits and clothings by using a flat knitting machine. In the Milano rib knitting, rib knits are formed by the knitting needles of the first and second needle beds disposed so as to confront in the reverse V-form, and flat knitting is done by the knitting needle of the first needle bed and also flat knitting is done by the knitting needle of the second needle bed, and by repeating this formation, knitting is completed.
Thus, generally, thick fabrics are knitted by the combination of rib knitting and flat knitting. However, although the knit fabric is thick, since the fundamental texture is the combination of rib knitting and flat knitting, the excessive elasticity in the lateral direction of the rib knitting cannot be removed sufficiently even by the flat knitting to communicate with the adjacent loop by the shortest distance. Therefore, a firm fabric less in elasticity is not obtained, and the knit products tends to be deformed.
SUMMARY OF THE INVENTION
In the light of the above points, it is hence a primary object of the invention to present a method of obtaining a knit fabric which is firm and solid as compared with the conventional knit fabric, so as to be less in elasticity and less likely to deform when knitting a thick fabric by using a flat knitting machine.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects and the attendant advantages of the present invention will become readily apparent by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:
FIG. 1, FIG. 2, FIG. 3 and FIG. 4 are knitting diagrams;
FIG. 5 is a loop diagram of the fabric knitted by a knitting method illustrated in FIG. 1;
FIG. 6 is a loop diagram of the fabric knitted by a knitting method illustrated in FIG. 4; and
FIG. 7 and FIG. 8 are views of a knit product knitted by a knitting method of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, some of the preferred embodiments of the knitting method of the invention are described in detail below.
To realize the invention, the knitting machine is a flat knitting machine comprising a pair of needle beds abutting at the front end, for example, two front and rear needle beds disposed opposedly in the reverse V-form, and a carriage reciprocating on each needle bed in the front and rear positions (not shown). The knitting machine includes a pair of cams which are capable of selecting and guiding the knitting needles to a cam path for loop transfer or a cam path for extending needles to receive the yarn within the same carriage as knitting cams capable of selecting and guiding the knitting needles to three positions of knit, tuck and welt.
FIG. 1 to FIG. 4 show preferred embodiments of the knitting method of the invention applied entirely to the fabric to be knitted. For the same of convenience of description, the number of knitting needles used in knitting in each embodiment is set to a small number.
In the figures, alphabetical capital letters A, B, C, D, E, F, represent knitting needles of the front needle bed 6 and alphabetical small case letters a, b, c, d, e, f represent knitting needles of the rear needle bed 7.
FIG. 1 is a knitting diagram showing a first embodiment, and a loop diagram of the fabric knitted by this knitting is given in FIG. 5. In block 1 in FIG. 5, a loop 10 of the previous course held on the front knitting needle is made to be held also on the rear knitting needle on the rear needle bed 7, while the same thread is supplied to the front knitting needle and a new loop 11 is formed going through the loop 10. This knitting course is called "split-knit", which is defined as knitting on both front and rear beds in the same course.
That is, the needle loop of the loop 10 of the previous course overlaps with a loop 20 of the previous course stopped on the knitting needles of the second needle bed 7, and is also entangled on a sinker loop 11a of the new loop 11 formed by the knitting needles of the confronting first needle bed 6 to be pulled to the side of the first needle bed 6, and the loop 10 straddles over the first and second needle beds 6, 7, and the tension of the threads increases, and the fabric is less in elasticity and firm.
Next, in block 2, flat knitting is done by the knitting needles of the second needle bed 7 to form a loop 21, and in block 3, flat knitting is done by the knitting needles of the first needle bed 6, thereby forming a loop 12. Thereafter, these three blocks are repeated to knit the fabric, but the loop 12 formed in block 3 overlaps with the loop 21 formed in block 2 by the successive transfer or split knit, and it is also entangled in a new loop 13 formed by this transfer or splite knit.
In other words, these loops in series are intended to make the fabric thicker by continuously forming a space of nearly square shape to the fabric section every time the basic knitting is repeated.
FIG. 2 is a knitting diagram showing a second embodiment, in which, similar to FIG. 1, split-knit is effected in block 1 and a new loop is being formed on the front knitting bed 6. In block 2, a thread is supplied to the rear knitting needles and a new loop is formed on the rear knitting needle. Thereafter, these two blocks are repeated to knit.
FIG. 3 is a knitting diagram showing a third embodiment, in which, in block 1, transfer knit is effected by the knitting needles of the first needle bed 6, and in the subsequent blocks 2, 3, flat knitting is effected by the knitting needles of the second and first needle beds 7, 6, respectively, and in block 4, again, flat knitting is done by the knitting needles of the second needle bed 7. Thereafter, these four blocks are repeated to knit.
FIG. 4 refers to a fourth embodiment, in which, in block 1, transfer knit is carried out by the knitting needles of the first needle bed 6, and in blocks 2, 3, flat knitting is done by the knitting needles of the second and first needle beds 7, 6, respectively, and in the subsequent block 4, flat knitting by the knitting needles of the second needle bed 1 is performed, and in block 5, the loop stopped on the knitting needles of the second needle bed 7 formed in block 4 is moved to the knitting needles of the first needle bed 6. Thereafter, these five blocks are repeated to knit.
FIG. 6 shows a fabric knitted by the knitting method in the fourth embodiment, and a loop diagram after several repetitions of the above knitting is illustrated, and the start position indicates the point of start of block 1 after block 5. In block 1, transfer or split knit is performed by the knitting needles of the first needle bed, and a loop 30 formed by the knitting needles of the first needle bed 6 of the previous course stopped by the knitting needles, and a loop 40 formed by the knitting needles of the second needle bed 7 are moved to the knitting needles of the confronting second needle bed 7, while threads are supplied to the knitting needles of the first needle bed 6, and a new loop 31 is formed by moving under the loops 30, 40 to be moved.
In this case, the needle loop of the loops 30, 40 of the previous course is moved to the knitting needle of the second needle bed 7, and is also entangled in a sinker loop 31a of the new loop 31 formed by the knitting needles of the confronting first needle bed 6 to be pull to the side of the first needle bed 6, so that the loops 30, 40 straddle over both first and second needle beds 6. 7. Hence, the thread tension is heightened, the elasticity of fabric becomes less, and the fabric is firm. Successively, in block 2, by performing flat knitting by the knitting needles of the second needle bed 7, a loop 41 is formed, and in block 3, a loop 32 is formed by flat knitting by knitting needles of the first needle bed 6, and in block 4, again, flat knitting is effected by the knitting needles of the second needle bed 7, thereby forming a loop 42.
This loop 42 formed in block 4 is moved to the knitting needles of the first needle bed 6 in block 5, and overlaps with the loop 32 stopped by the same knitting needles. In the case of the method of the invention, too, these loopes in series make the fabric thicker by continuously forming the space in an approximately square shape slightly different from the previous example to the fabric section every time the basic knitting is repeated.
In a fifth embodiment (not shown), before the transfer or split knit to be repeated of each knitting in block 1 to 3 in the first embodiment shown in FIG. 1, the loop stopped on the knitting needles of the second needle bed 7 is moved to the knitting needles of the first needle bed 6 as shown in block 5 in FIG. 4. Thereafter, these four blocks are repeated to knit.
In a sixth embodiment (not shown), prior to transfer or split knit to be repeated of each knitting in blocks 1 and 2 in the second embodiment shown in FIG. 2, the loop stopped on the knitting needles of the second needle bed 7 is moved to the knitting needles of the first needle bed 6 as shown in block 5 in FIG. 4. Thereafter, these three blocks are repeated to knit.
By such transfer or split knit, the flat knit loops knitted by the first and second needle beds are overlapped by threads of about half of the length as compared with the ordinary rib knitting, and therefore the loops are engaged with a higher tension, and the knit fabric is less in elasticity and is less likely to deform. Moreover, by the repeated fabrics, a series of loops becomes continuous while forming a space of approximately square shape to the fabric section, so that the fabric may be more firm and secure as compared with the conventional products.
Besides, in the prior art, the end portion of knit fabric products was reinforced in the subsequent process of knitting, or by plating stitch of knitting together with two eyelet levers. By contrast, in the knitting method of the invention, by executing this method on an arbitrary number of wales at the end portion of the fabric, it is possible to reinforce completely by one eyelet lever, and the productivity may be enhanced.
Meanwhile, needless to say, in the foregoing embodiments, the sequence of flat knitting of the first and second needle beds may be exchanged. Besides, when flat knitting is effected on several wales of the selvage of knitting, a clean end stitch may be formed.
The knitting method of the invention is not limited to the foregoing embodiments alone. For example, as shown in FIG. 7 or FIG. 8, the knitting method of the invention may be applied to an arbitrary number of wales of the knit fabric. Specially, FIG. 7 shows a sleeve 100 in which the knitting method of the invention is applied to the wale middle process 3 of the knit fabric, and FIG. 8 show a vest 101 in which the knitting method of the invention is applied in the wale end portion 4 of the knit fabric, and other modifications may be also possible as far as not departing from the true spirit of the invention. | The invention is directed to a method of knitting a thick fabric, which is less in elasticity, less likely to deform, and firmer than a conventional fabric. The method is performed by using a flat knitting machine possessing a transfer lock capable of selecting and guiding the knitting needles to the loop transfer track or loop receiving track within the same phase as at least one knitting lock capable of selecting and guiding the knitting needles to three positions of knit, tuck and welt. | 3 |
SUMMARY OF THE INVENTION
[0001] An expandable platter/tray that holds dishes, trays, etc. The structure comprises a frame within a frame, with each frame having a pair of parallel tracks. An inner frame tracks slides within the outer frame's tracks. Thus the length of the entire structure can be fixed by inserting holding wires vertically through the holes in the tracks thereby preventing the tracks from moving relative to one another. All of the tracks have precisely spaced holes so that wires, which are in general shape of a “U”, straddles both sides of the tracks and is inserted into the holes of the outer tracks and/or holes of the inner and outer tracks. The “U” shaped wires can hold the platters, plates, dishes, etc. from leaning on each other in the lengthwise direction, as well as fixing the movement of the frames relative to each other. The tracks are supported by legs. The bottom of the legs of the frames rest on glides themselves that glide in the direction perpendicular to the tracks. The tracks on which the glides rest are attached to the bottom of a cabinet. Thus the entire platter/tray structure, whose length has been fixed by the wires, is also free to glide outwards so that the platter tray can easily be seen and handled before being re-glided back into the cabinet. The invention allows an expandable platter tray to expand to within any size cabinet.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a holder of platters, trays, plates, etc. in kitchen cabinets. It is desirable to have such a holder that fits any of the many cabinet sizes. This invention meets that need by being expandable. Once a length has been decided this structure has the means of being fixed in length. It is also desirable for there to be a means of gliding outwards of the cabinet the platters, trays, plates, etc. from the kitchen cabinet so that these items may be inspected, used, washed, and rearranged. This invention meets these needs by being mounted on glides, which have been attached to the bottom of the cabinet.
BRIEF DESCRIPTION OF PHOTOGRAPHS
[0003] PHOTO 1 is a photograph of the tracks partially extended that slide lengthwise within tracks. Legs support both sets of tracks.
[0004] PHOTO 2 is a photograph of the inner tracks more fully extended from the outer tracks.
[0005] PHOTO 3 is a photograph of the tracks mounted on a representation of glides. The glides have screw holes for mounting inside a kitchen cabinet,
DETAILED DESCRIPTION OF THE INVENTION
[0006] Referring to the photographs initially to Photo 1 , an Expandable Platter/Tray in accordance with the present invention, comprises an inner set of two tracks 3 within both sides of a frame 2 , 4 , 7 , 8 and an outer set of two tracks 4 , 7 which is also the frame. The frame and tracks are supported on both sides by legs 1 , 2 , 8 . The inner tracks can be pulled out of the frame to fit the inner length of a cabinet. Both sets of tracks have holes 7 accurately spaced so that wires in the general shape of an inverted letter “U” can be pushed through the holes to stop relative movement between the inner and outer tracks while also serving to separate and hold plate/platter, etc. from movement in the Y direction. The tracks support plates from movement in the X direction.
[0007] Referring to Photo 2 , the inner tracks are drawn outward of the frame in the Y direction. The length of extension depends on its desired fit in the kitchen cabinet. The U-shaped inverted wires would be inserted into the holes parallel to the tracks in the X direction to separate platter/trays, etc.
[0008] Referring to Photo 3 , the aforementioned legs of the frame are themselves mounted on glides represented by 5 and 6 . The glides allow the entire frame holding platters/trays etc. movement in the X direction. This serves as a “pull out” from the kitchen cabinet for easy access. The glides have means of being fastened to the floor of kitchen cabinet, such as holes 11 for screws. The inner rails have a “blocker” 9 to keep the ends of inner tracks from movement in the X direction.
EXAMINATION OF THE REFERENCES
[0009] (1) U.S. Pat. No. 5,121,681 to Chang, discloses an extendable bookshelf. FIGS. 2 and 3, in particular, show the bookshelf in an extended mode (as compared with FIG. 1 that shows the bookshelf in a non-extended mode). As shown in FIG. 2 of Chang, a series of holes 14 are made in a base 10, and a slide 20, which fits within the base 10, also has holes 21 which correspond to the holes in the base. The degree of extension of the bookshelf is based upon placing a stay 40 (which is referred to at column 2, lines 5-6 as being U-shaped), the stay having a pair of legs 40 coupled by an arm 42 on which a cushioning sleeve 43 is placed to provide the user with some degree of comfort and grip when changing positions. When the inner slide 20 is moved out of the channel 12 of base 10 an L-shaped extension comprising a first limb 46 and a second limb 47 can engage in the holes 21 of the slide 20. There are also two stays 30 that are positioned across the shelf so as to provide an area in which the books can be stably secured to the shelf. It is clear from Chang that the stays are of sufficient length so that any of them could be pressed down through the holes of the base portion 10 and the slide.
[0010] (2) U.S. Pat. No. 5,330,063 to Remmers, discloses an organizer glide system, whereby a base frame 12 has a pair of support rails 14 attached thereon, the base frame being attached to the bottom of a wire basket organizer 16 which permits (as shown in FIGS. 9 and 10 the basket be slid in and out along the rails.
[0011] (3) U.S. Pat. No. 4,720,016 to Kay, discloses a closet storage system, whereby an extension 20 is extended from a bracket 10 and is held by E-Clip 40 to which a pin 52 (as best shown in FIG. 4) fits through the aligned holes in the E-C lip and those of the bracket and/or extension member 20.
[0012] (4) U.S. Pat. No. 4,410,093 to Chiariello et al., discloses a desk organizer for organizing papers and files having a series base members 12 that have slots 12J in which a plurality of wire dividers 22 are placed therein.
[0013] (5) U.S. Pat. No. 4,036,369 to Eisenberg, discloses an expandable rack which has (as shown in FIG. 1) a shelf means 12 consisting of an inner most section 14 and an outer shelf 16, both of which having flanged edges and receivably arranged within each other so as to permit telescopic extension.
[0014] (6) U.S. Pat. No. 6,021,908 to Mathews, discloses an extendable display shelf, which is best shown in FIGS. 3 and 4, and includes shelves 40 having bracket arms 42, which are individually secured to vertically extending space apart uprights 44, with the bracket arms 42 having outwardly extending teeth 46 to be received in the uprights. The bracket arms 42 include an extension 62 that is telescopingly received within the bracket arm and via a spring detent 64 is urged into engagement with linear holes 66 in the side of the bracket arm 42. The extension arm 62 is adjusted to the desired depth of the shelf by pushing the detent 64 through the hole 66 and moving the extension in or out.
[0015] (7) U.S. Pat. No. 3,760,744 to Cruckshank, discloses an “expansible” shelf addition comprising two telescoping sheet metal members, each member having a plurality of linear equally close spaced perforations, and wire-formed supporting end legs that are attached through the perforations. As shown in FIG. 1, the sheet members can be adjusted to a specific length whereby a generally Ushaped center leg 15, referred to as a unitary wire formed member has upper free ends 44 and 45, which will extend through the perforations as shown in FIG. 1 to lock the members in place.
[0016] (8) U.S. Pat. No. 2,946,458 to P. Du Boff et al., discloses reciprocating tray units, wherein a kitchen cabinet or cupboard 1 has a reciprocating tray unit 4 with rails 8, 10 extending along opposite sides of the cabinet. A tray member 22 is reciprocatively mounted on a base member 6 by a coupling 24 and can be slide and/or moved outwardly to a convenient position from the cabinet secured from a shelf C, and slide outwardly so that the cup B can be removed from the rack.
[0017] (9) U.S. Pat. No. 1,974,983 to H. A. Cook, discloses a cabinet shelf, whereby a shelf 18 can slide along a fixed rack 19 to permit access to items in the back of the cabinet shelf.
[0018] (10) U.S. Pat. No. 1,095,073 to G. B. Bish, discloses a skirt hanger for cabinets, whereby a plurality of resilient garment engaging members 30 are carried by a supporting member 23, wherein when a garment is desired to obtained from the case, a handle 36 is pulled and the slidably mounted garment supporting member drawn up far enough to get the desired garment. | A platter/tray holder consisting of tracks within tracks that expands to the length of the insides of a cabinet. Wires, in the shape of the inverted letter U, are, inserted vertically through holes in the tracks to fix the tracks and serve as separators to the platters, trays, plates, etc. The tracks, supported by legs, are themselves mounted on glides. The glides, attached to the bottom of the cabinet, slide in a perpendicular direction to the tracks and allow the entire platter/tray to be glided in and out of the cabinet for easy viewing and utilization. | 0 |
RELATED APPLICATION
The present application is a continuation-in-part, under 35 U.S.C. § 120, of Applicant's co-pending U.S. patent application Ser. No. 09/933,030 filed Aug. 20, 2001. By this reference, the entire disclosure of U.S. patent application Ser. No. 09/933,030 is incorporated herein as though now set forth in its entirety.
FIELD OF THE INVENTION
The present invention relates to systems and methods for weight loss and body fat management. More particularly, the invention relates to methods and apparatus wherein previously proposed weight loss modalities are combined in a manner designed to produce weight loss results not available through their individualized or uncoordinated usage.
BACKGROUND OF THE INVENTION
Collagen-based formulas have been reported to increase lean body muscular mass and promote fat loss when taken as a dietary supplement. Although the exact physiology is not known, it is believed that the collagen-based formula enhances the known physiological processes for the metabolism of fat and muscle as influenced by the complex interplay between insulin, exercise and stress and other hormones. Regardless of the physiological basis, however, the reported weight loss results speak for themselves.
Other unrelated studies have reported that persons receiving mild electrical currents into their bodies have experienced weight loss. While the underlying causes for the weight loss are not completely understood, it is believed that the electrical currents cause the sympathetic nervous system to produce catecholemines, which in turn attach to receptor sites on fat cells. As a result, it is believed that free fatty acids are released into the blood stream. Depending on the user's exercise regime and dietary habits, the released free fatty acids may be converted to more useful products.
Although each of the foregoing modalities is associated with weight loss, no suggestion for their combination has been made. Applicant has found, however, that the combination of the foregoing modalities according to a strictly timed protocol can produce weight loss results far faster either modality alone or through the combination of the foregoing modalities in noncompliance with the discovered time protocol. It is therefore an overriding object of the present invention to set forth a protocol for combining electrical stimulation therapy with the ingestion of a collagen-based formula such that results in synergistic weight loss.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects, the present invention—a protocol for body fat management—generally comprises the steps of stimulating the release of free fatty acids into the bloodstream of a person and, within 20 minutes thereafter, ingesting into the person a collagen-based formula. The stimulating step may be conducted by delivering a low voltage alternating current to the person's body, which may be accomplished utilizing an electronic stimulation device to deliver the current to the feet of the person. The device may be provided with the capability for adjustment of both the voltage level and frequency of the current as well as the capability to enable operation of the device only upon payment to a service provider of a fee.
Finally, many other features, objects and advantages of the present invention will be apparent to those of ordinary skill in the relevant arts, especially in light of the foregoing discussions and the following drawings, exemplary detailed description and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the scope of the present invention is much broader than any particular embodiment, a detailed description of the preferred embodiment follows together with illustrative figures, wherein like reference numerals refer to like components, and wherein:
FIG. 1 shows, in a flowchart, the preferred body fat management protocol of the present invention;
FIG. 2 shows, in a functional block diagram, details of an electronic stimulation device utilized as part of the protocol of FIG. 1 ;
FIG. 3 shows, in a schematic diagram, details of the electronic stimulation device of FIG. 2 ;
FIG. 4 shows, in flowchart, steps taken in the utilization of the electronic stimulation device of FIG. 2 within the protocol of FIG. 1 ;
FIG. 5 shows, in flowchart, certain details of the utilization of the electronic stimulation device according to the steps outlined in FIG. 4 ;
FIG. 6 shows, certain other details of the utilization of the electronic stimulation device according to the steps outlined in FIG. 4 ; and
FIG. 7 shows, in flowchart, details regarding control of the electronic stimulation device of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Although those of ordinary skill in the art will readily recognize many alternative embodiments, especially in light of the illustrations provided herein, this detailed description is exemplary of the preferred embodiment of the present invention, the scope of which is limited only by the claims appended hereto.
Referring now to the figures, and to FIG. 1 in particular, the preferred weight loss protocol 10 of the present invention is shown to generally comprise the ingestion 11 of a collagen-based formula within a critical time window following the usage 12 of an electronic stimulation device 13 . As will be better understood further herein, the electronic stimulation device 13 serves to stimulate reduction of fat cells as a key part of the novel weight loss protocol 10 . In particular, Applicant has found that ingestion 11 of a collagen-based formula on an empty stomach and within 20 minutes following usage 12 of the electronic stimulation device 13 produces weight loss results not attainable through the independent, uncoordinated usage 12 of the electronic stimulation device 13 and ingestion 11 of the collagen-based formula.
As shown in FIG. 2 , the preferred embodiment of the electronic stimulation device 13 generally comprises a stimulation control module 14 , adapted to deliver 15 a low current voltage to the user's body, and a spectral analysis circuit 16 , adapted to determine 17 the optimum frequency for conduction into the user's body of the low current voltage. Although much of the benefit of the present invention may be attained utilizing a simplified version of the electronic stimulation device 13 having the minimal capability to deliver 15 a low current voltage to the user's body, those of ordinary skill in the art will recognize, in light of this exemplary disclosure, that the features of the preferred embodiment directed toward adjustment of voltage level and treatment frequency are highly desirable in order to ensure that the user receives the maximum weight loss benefit available from the described protocol 10 . In any case, the preferred embodiment of the invention utilizes a pair of specially manufactured, electrically conductive “socks” or “slippers,” or the substantial equivalent thereof, to provide electrical contact between the electronic stimulation device 13 and the user's feet. Appropriate socks and slippers are described in detail in Applicant's co-pending U.S. patent application filed on Mar. 11, 2002 in the names of David M. TUMEY and Teryl B. SANDERS, which by this reference is incorporated herein as though now set forth in its entirety.
As shown in FIG. 3 , the preferred embodiment of the stimulation control module 14 comprises a frequency control circuit 18 , for controlling the frequency of the delivered current signal, and a voltage control circuit 19 , for controlling the amplitude of the delivered current signal. In particular, the frequency control circuit 18 comprises an operational amplifier 20 , configured as a comparator, which in turn drives a 555 integrated circuit timer 21 , configured as a monostable oscillator, according to the level of an input signal. As will be better understood further herein, the input 22 to the comparator 20 is interfaced to a controller 23 , which provides the input signal according to a determination utilizing the spectral analysis circuit 16 of which frequency is best conducted into the feet of the user. The output 24 from the monostable oscillator is then utilized to drive the gate of a medium power MOSFET 25 . The transistor's source and drain circuits are in series with a 10 to 1 step-up transformer 26 , which interfaces the stimulation control module 14 through a plurality of jacks 27 to the electrically conductive socks or slippers.
Likewise, the controller 23 is connected to an envelope detector 28 configured to drive the positive input 29 of an operational amplifier 30 , the output 31 of which is also connected to the step-up transformer 26 . The signal supplied from the controller 23 to the envelope detector 29 is determined based upon an adjustment made by the user through an appropriate input device such as, for example, a variable resistor 32 or the like. In this manner, both the amplitude and the frequency of the signal generated through the step-up transformer 26 may be controlled.
Finally, as also shown in FIG. 2 , the spectral analysis circuit 16 generally comprises a current amplifier 33 having inputs 34 connected across a shunt resistor 35 in the output of the step-up transformer 26 . In this manner, the current amplifier 33 may monitor current flow through the socks or slippers and into the user's feet. The output from the current amplifier 33 is then communicated to the controller 23 as part of a spectral sweep 36 to determine which frequency or frequencies are best conducted into the user's feet. In operation, the controller is adapted to generate 36 a sweep of frequencies (through the frequency control circuit 18 ) in response to an input from the user such as, for example, depression of a momentary switch 37 connected to an input to the controller 23 . During the spectral sweep 36 , the controller 23 is utilized to determine which frequency or frequencies are best conducted into the feet of the user. As described above, the determined best frequency is stored and utilized for the delivery 15 to the user of the stimulation voltage.
Referring again to FIG. 1 , the preferred protocol of the present invention is detailed. According to the preferred protocol, a user wishing to lose weight with the assistance of the present invention is directed to fast 38 for at least three hours prior to bedtime. If, however, the user should have difficulty abstaining from food or carbonated or sugary beverages for the full three hour period, the present invention also comprises the utilization 39 of an electronic appetite suppressor. The electronic appetite suppressor generally comprises a headphone type device adapted to produce a mild electrical current at known acupuncture points near the ears which induces in the user a sense of well being similar to that obtained through acupuncture techniques. Exemplary of such an electronic appetite suppression device is that which is described in Applicant's co-pending U.S. patent application entitled “APPETITE SUPPRESSION DEVICE,” filed in the name of David M. TUMEY on Feb. 4, 2002, which by this reference is incorporated herein as though now set forth in its entirety. In any case, the user then makes use 12 of the electronic stimulation device 13 during the final 10 minutes to one hour prior to bedtime. Use 12 of the electronic stimulation device 13 (as described in greater detail further herein) is thought to activate the sympathetic nervous system in the production of catecholemines. The produced catecholemines then attach to receptor sites on the user's fat cells, thereby releasing free fatty acids into the blood stream. Upon completion of the electronic stimulation therapy, the user consumes 11 a collagen-based formula and retires 40 to bed. As the user sleeps, the collagen-based formula utilizes the released free fatty acids for tissue, muscle and bone repair. In this manner, body fat is effectively is redistributed and converted into more healthy tissues.
As shown in FIG. 4 , the use of the electronic stimulation device preferably begins with the user placing one foot only into each of either the socks or the slippers and sitting comfortably in a chair. The appropriate treatment frequency is then determined 17 and the therapy delivered 15 , each as described in greater detail further herein. Although those of ordinary skill in the art will recognize that the treatment frequency may be manually selected or may be determined a priori based upon empirical data, it is preferred that an analysis be performed each time the electronic stimulation device 13 is utilized in order to determine 17 which frequency or frequencies are best conducted into the user's feet at that time. In this manner, factors such as hydration and the like may be accounted for, thereby ensuring that the user will receive the maximum benefit of the described protocol 10 .
As shown in FIG. 5 , a low voltage and low current spectral sweep preferably encompassing frequencies from about 100 Hz to about 10 kHz is first performed 36 (at the direction of the user as determined by detecting depression of the switch 37 connected to the provided input to the controller 37 ). During the spectral sweep 36 , the spectral analysis circuit 16 is utilized to measure the current conducted into the user's feet. The measurements are then processed to identify 41 the peak energy point or points, which are correlated 42 with the frequency or frequencies responsible for their generation.
As detailed in FIG. 6 , once the treatment frequency has been determined 42 , the therapy is delivered 15 by first setting 43 the therapy frequency according to the previous determination 42 . Under the control of the voltage control circuit 18 , the lowest level current is then delivered 44 at the set treatment frequency through the socks or slippers to the user. The user then adjusts 45 the treatment voltage level, by adjustment of the input device 32 connected to the corresponding input to the controller 23 , until a slight “tingling” sensation is felt in the feet. Upon generation of sufficient current to produce a tingling sensation indicative of current flow through the user's feet, a treatment timer is started 46 in order to deliver 15 8 to 20 minutes of therapy to the user, although up to one hour of therapy is thought to contribute to the synergistic weight loss results produced through the protocol 10 of the present invention.
Upon completion of the electronic stimulation, the user consumes 11 the collagen-based formula. As previously discussed, it is critical that this consumption take place within 20 minutes following the electronic stimulation 12 in order to achieve the synergistic effect of combining these weight loss modalities. Additionally, it is noted that the user should retire 40 to bed within about 15 minutes following consumption 11 of the collagen-based formula in order to ensure that the user's body is in a sleeping state for a substantial portion of the 90 minute window during which the collagen-based formula is most efficacious.
While the foregoing description is exemplary of the preferred embodiment of the present invention, those of ordinary skill in the relevant arts will recognize the many variations, alterations, modifications, substitutions and the like as are readily possible, especially in light of this description, the accompanying drawings and claims drawn thereto. For example, as shown in FIGS. 4 and 7 , it may be desirable for the controlled commercialization of the described protocol 10 to provide a means by which the operation of the electronic stimulation device may be dependent upon satisfaction of some criteria, such as the establishment 47 of credit with a service provider. To this end, provision is made in at least one embodiment of the protocol 10 for the establishment 47 of credit as a prerequisite to the enabling 48 of the controller 23 for operation.
As shown in FIG. 7 , the establishment 47 of credit may involve the periodic establishment 49 of communication with the service provider. As will be appreciated by those of ordinary skill in the art, the establishment 49 of communication may be through a MODEM connection, Internet connection or any substantial equivalent thereof. In any case, once it is determined 50 that the user is “paid up” or otherwise authorized to make use of the general protocol 10 , appropriate authorization codes are stored 51 within the controller 23 in order that the user may then make use of the device at any time or place so long as his or her authorization remains valid. This may be for a number of therapy minutes or may be based upon the passage of a number of days or may be based upon any other substantially equivalent measurement technique. In any case, because the scope of the present invention is much broader than any particular embodiment, the foregoing detailed description should not be construed as a limitation of the scope of the present invention, which is limited only by the claims appended hereto. | A protocol for body fat management comprises the steps of stimulating the release of free fatty acids into the bloodstream of a person and, within 20 minutes thereafter, ingesting into the person a collagen-based formula. The stimulating step may be conducted by delivering a low voltage alternating current to the person's body, which may be accomplished utilizing an electronic stimulation device to deliver the current to the feet of the person. The device may be provided with the capability for adjustment of both the voltage level and frequency of the current as well as the capability to enable operation of the device only upon payment to a service provider of a fee. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to the labeling of objects by the use of heat to transfer design prints from a carrier to the objects being labeled.
In heat transfer labeling, a design print that is affixed to a carrier by a release layer is brought into contact with an object to be labeled. When heat is applied to the carrier the release layer becomes molten and permits the design print to become adhered to the object.
In the typical heat transfer label, as exemplified by U.S. Pat. No. 3,616,015, which issued Oct. 26, 1971, the release layer is a coating of wax on the carrier and the design print is in a transfer layer that is printed on the wax coating. With such a label, the application of heat during the transfer process causes a film of wax to be deposited over the entire region where the carrier is in contact with the object being labeled. The deposited film is of random configuration and is frequently much larger than the design print.
Although the wax film is transparent and generally not noticeable by casual observation, under certain lighting conditions the film is viewable and can present an objectionable appearance. The resulting film can be regarded as an expanded, irregular "halo" that surrounds the design print. Not only can the irregular halo present an objectionable appearance, it represents a wastage of material. Moreover, because of the tendency of the wax to penetrate the carrier material used in ordinary heat transfer labeling, a substantial amount of wax material is needed to form the transfer coating.
Accordingly it is an object of the invention to expedite and facilitate the heat transfer labeling of objects.
Another object of the invention is to improve the appearance of heat transfer labels. A related object is to eliminate the enlarged, irregular halo often encountered in heat transfer labeling.
A related object is to economize on the amount of material needed for the release layer in the heat transfer labeling of objects.
SUMMARY OF THE INVENTION
In accomplishing the foregoing and related objects, the invention provides for the use of a thermoplastic release layer containing a repellent material such as silicone. The release layer is contoured in accordance with a prescribed pattern and is in registration with a transfer layer.
Since the release layer is contoured, it does not present an irregular appearance. Further the contoured pattern can be made to closely approximate the contour of the transfer layer and thereby significantly reduce the extent of the halo.
In accordance with one aspect of the invention the halo can be completely eliminated by having the confines of the transfer layer exceed those of the release layer.
In accordance with a further aspect of the invention the release layer is applied by printing, instead of coating the carrier. This significantly reduces the amount of material needed. In addition when the release material is a resin, as opposed to a wax, there is less absorption by the carrier and less material is needed.
Printing of the release layer also eliminates the need for a coating operation in conjunction with the printing operation by which the transfer layer is applied to the carrier.
DESCRIPTION OF THE DRAWINGS
Although aspects of the invention will become apparent after considering several illustrative embodiments taken in conjunction with the drawings in which:
FIG. 1A is a plan view of heat transfer label carrier of the prior art;
FIG. 1B is a sectional view of the carrier of FIG. 1A;
FIG. 1C is a perspective view of an object that has been labeled using the carrier of FIG. 1A;
FIG. 2A is a plan view of a heat transfer label carrier in accordance with the invention;
FIG. 2B is a sectional view of the carrier of FIG. 2A;
FIG. 2C is a perspective view of an object that has been labeled using the carrier of FIG. 2A; and
FIG. 3 is a plan view of an alternative heat transfer label in accordance with the invention.
DETAILED DESCRIPTION
With reference to FIGS. 1A through 1C of the drawings, a carrier 11 (FIGS. 1A and 1B) in accordance with the prior art is provided with a coating 12 upon which is superimposed a transfer layer 13 which includes a design print.
When the transfer layer 13 of the carrier 11 is brought into contact with an object to be labeled, such as the illustrative container 14 of FIG. 1C, and heat is applied, the wax coating 12 melts and allows the contacting portion of the transfer layer 13 to adhere to the container 14. Simultaneously a wax film 15 is deposited on the container 14. This film is of irregular configuration and considerably larger than the transferred design print 16. Under certain viewing conditions the film 15 presents an objectionable appearance.
To remedy the foregoing difficulties, the invention provides the heat transfer labeling arrangement of FIGS. 2A and 2B in which a contoured release layer 22 is applied to the carrier 21 and a transfer layer 23 is superimposed on the release layer. As a result, when the transfer layer 23 is brought into contact with an object to be labeled, such as the illustrative container 24 of FIG. 2C, the transferred design print 25 has superimposed on it a release layer which provides a contoured halo 26 with a narrow margin.
If it is desired to eliminate even the narrow halo 26, this can be done, as shown in FIG. 3, by forming the heat transfer label with a contoured release layer 32 that is within the confines of a transfer layer 33. When this label is applied to an object the design print from the transfer layer 33 is coextensive with the boundaries of release layer 32.
The release layers 22 and 32 are applied to a carrier by printing. For that purpose suitable materials are soluble resins such as polyamides, polystyrenes, rosin derivatives, phenol formaldehydes, terpene resins and ketone resins. Suitable solvents include alcohols and toluenes, and various mixtures of the same. A small amount of glycerine is added to achieve repellency, i.e. non-tackiness in the finished product. A suitable material for the transfer layers 23 and 33 is the resin isobutylmethacrylate, which desirably has a low melt viscosity in the range from 3.5 to 8.5 poises at 160 degrees centrigrade, and a softening point in the range from 95° to 106° C.
The practice of the invention is further illustrated with reference to the following non-limiting examples:
EXAMPLE I
A polyamide resin sold and marketed under the trade name EMEREZ 1538 of Emery Industries was dissolved in 70 parts isopropyl alcohol and 30 parts toluene to form a solution with a concentration of 30 percent resin. To this is added silicone in the range between 1 and 5 percent. The resulting solution is printed in a contoured pattern on a paper carrier of conventional bodystock for heat transfer labeling using a rotogravure press. The print pattern is dried to remove the solvent and overprinted with a transfer layer, formed by an ink lacquer of isobutylmethacrylate, in a contoured pattern in registration with the release pattern. The doubly imprinted carrier stock is used to apply the design print of the ink lacquer to an object to afford good transfer with an insignificant release halo and suitable repellency.
Other appropriate polyamide resins of the EMEREZ type are sold and marketed under the trade names EMEREZ 1536 and 1537.
EMEREZ polyamide resins have the characteristics illustrated in TABLE I, below.
TABLE I______________________________________CHARACTERISTIC EMEREZ 1536 EMEREZ 1538______________________________________Softening point range 95-105 98-106(degrees centigrade)Melt Viscosity 3.5-5.0 6.5-8.5(poise at 160 degreescentigrade)Molten Color 12 10(1963 Gardner)Viscosity in 40% Mixed 66 82Solvent(cps at 25° C.)Viscosity in 40% 62 95n-Propanol(cps at 25° C.)______________________________________
EXAMPLE II
Example I is repeated using a polyamide sold and marketed under the trade name VERSAMID 940 by General Mills. Satisfactory release is afforded with an insignificant release halo.
EXAMPLE II
Example I is repeated using a polyamide sold and marketed under the trade name VERSAMID 948. Satisfactory release is afforded.
EXAMPLE IV
Example I is repeated using a polystyrene resin sold and marketed under the trade name LUSTREX 3 using toluene as the solvent. Satisfactory release is afforded with an insignificant release halo.
EXAMPLE V
Example IV is repeated with a similar result using a rosin derivative sold and marketed under the trade name PENTALYN A.
EXAMPLE VI
Example IV is repeated with a similar result using a modified phenol formaldehyde sold and marketed under the trade name AMBEROL F-7.
EXAMPLE VII
Example IV is repeated with a similar result using a terpene resin sold and marketed under the trade name PICCOLYTE S-100.
EXAMPLE VIII
Example IV is repeated with a similar result using a ketone resin sold and marketed under the trade name ADVARESIN CXF.
It will be understood that the foregoing examples and description are illustrative only and that other examples and equivalents within the spirit and scope of the invention will occur to those skilled in the art. | Product and process for heat transfer labeling employing a contoured thermoplastic and resinous release layer which is desirably imprinted on a carrier and superimposed with a transfer layer containing a design print. | 8 |
The present application is the United States national application corresponding to International Application No. PCT/US 93/02418, filed Mar. 24, 1993 and designating the United States, which PCT application is in turn a continuation-in-part of U.S. application Ser. No. 07/858915, filed Mar. 27, 1992, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to bis-aryl carbinol derivatives, pharmaceutical compositions and methods of using such derivatives.
International Publication Number WO 89/10369 discloses compounds of the formula: ##STR2## wherein: one of a, b, c and d represents nitrogen or --NR 11 --, wherein R 11 is, amongst others, O - , and the remaining a, b, c and d groups are CH; T represents carbon or nitrogen, with the dotted line attached to T representing an optional double bond when T is carbon; when m plus n equals 1 or 2, X represents, amongst others, --O-- or --S(O) e -- wherein e is 0, 1 or 2; when m plus n represents 0, X can be, amongst others, any substituent for m plus n equalling 1, a direct bond or propenylene; when m plus n equals 3 then X equals a direct bond; each R a may be, amongst others, H; Z represents ═O or ═S such that when Z is O, R may be, amongst others, ##STR3## wherein Y is N or NR 11 ; when Z represents ═S, R represents in addition to the R group above, aryloxy or alkoxy.
WO 89/10369 generically discloses compounds which can have the structure: ##STR4## wherein Z can be O and R can be: ##STR5## wherein Y can be NR 11 and R 11 can be --O - ; however, no specific compounds are disclosed with this structure.
U.S. Pat. No. 4,826,853 issued to Piwinski et al. on May 2, 1989 is the priority document for WO 88/03138 which published on May 5, 1988. WO 88/03138 discloses compounds of the formula ##STR6## wherein: one of a, b, c and d represents N or NR 9 where R 9 is, amongst others, O, and the remaining a, b, c and d groups are CH; X represents N or C, which C may contain an optional double bond to carbon atom 11; Z represents O, S or H 2 such that when Z is O, R may be, amongst others, ##STR7## when Z represents S, R represents in addition to the R group above, aryloxy or alkoxy; and when Z represents H 2 , R can be, amongst others, ##STR8## These compounds are disclosed as being useful in the treatment of allergy and inflammation.
In particular, WO88/03138 discloses intermediates having the formulas: ##STR9##
During the course of research on the compounds disclosed in WO 88/03138, it was generally found that the compounds having a carbonyl group (Z=O) attached to the piperidyl, piperidylidenyl or piperazinyl nitrogen atom were much stronger antagonists of platelet activating factor (PAF) than the compounds having a CH 2 group (Z=H 2 ) attached thereto.
WO 90/13548 published on Nov. 15, 1990 on PCT/US90/02251 which was filed on Apr. 30, 1990 and claims priority to U.S. application Ser. No. 345,604 filed May 1, 1989 discloses compounds similar in structure to the compounds disclosed in WO 88/03138 with the difference being that the R group represents an N-oxide heterocyclic group of the formula (i), (ii), (iii), or (iv): ##STR10## wherein R 9 , R 10 , and R 11 can be, amongst other groups, H.
European Patent Application, Publication No. 0 371 805, published Jun. 6, 1990, priority based on Japanese 303461/88 (30 Nov. 1988) and JP64059/89 (16 Mar. 1989) discloses compounds useful as hypotensives having the formula: ##STR11## wherein: X represents an aralkyl- or aryl-containing group having from 6 to 30 carbon atoms; Y represents a heteroatom or an optionally substituted alkylene chain, the alkylene chain optionally containing hetero atom(s) or unsaturated bond(s); and A represents an optionally substituted condensed aromatic or heterocyclic ring. It is also disclosed that if present, the aromatic ring of X or A is benzene, pyridine, pyridazine, or pyrazine, amongst others. Amongst the specific compounds disclosed there is included: (1) 4-(5H-Dibenzo[a,d]cyclohepten-5-ylidene)-1-(2-Picolyl)piperidine; (2) 4-(5H-Dibenzo[a,d]cyclohepten-5-ylidene)-1-(3-Picolyl)piperidine; and (3) 4-(5H-Dibenzo[a,d]cyclohepten-5-ylidene)-1-(4-Picolyl)piperidine. It is believed the structures of these compounds are: ##STR12##
Galantay et al., Journal of Medicinal Chemistry, 1974, Vol. 17, No. 12, pp. 1316 to 1327 discloses oxazole and thiazole analogs of amitriptyline. A disclosed intermediate has the formula: ##STR13##
U.S. Pat. No. 4,659,716 discloses an intermediate of the formula: ##STR14##
PCT/US89/01689, International Publication Number WO 89/10363, published Nov. 2, 1989, which generically discloses compounds of this invention, discloses compounds of the formula: ##STR15## wherein T represents ═O or ##STR16## Q represents CH, N or N→O; ring A represents defined heterocyclic aromatic rings (see pp. 3 and 4 for example); U is --H or --OH when the bond between W and the cyclohepta ring is a single bond (see, for example, Compound 17 in Reaction f on page 17); W represents C, N or N→O and the dotted line drawn to W from the cyclohepta ring represents an optional double bond when W is C, or is absent when W is N→O; and X can be, amongst others: ##STR17## wherein Z is O or S; R 1 can be, amongst others, H, alkyl, cycloalkyl, aryl, and heteroaryl (the definition of heteroatom includes N→O); and R x can be alkyl, aralkyl or aryl.
SUMMARY OF THE INVENTION
We have now unexpectedly found that compounds having a --OH group attached to the carbon atom, of the tricyclic ring system, to which the piperidine ring is attached, and having a pyridine N-oxide group bound to the piperidine nitrogen through a C═Z group, provide surprisingly good activity as PAF antagonists. It is believed that many of these compounds, along with their reduced pyridine counterparts (i.e., L represents N), are also good antihistamines.
In particular, we have discovered such characteristics in compounds represented by Formula I: ##STR18## or a pharmaceutically acceptable salt or solvate thereof, wherein
one of a, b, c, and d represents N or NO and the remaining others (i.e., the remaining a, b, c, and d) are C (carbon atoms); or all of a, b, c, and d represent carbon atoms;
L represents N or N + O - ;
R 1 , R 2 , R 3 , and R 4 are each independently selected from the group consisting of: H, halo, --CF 3 , --OR 11 , --C(O)R 11 , --SR 11 , --S(O) e R 12 wherein e is 1 or 2, --N(R 11 ) 2 , --NO 2 , --OC(O)R 11 , --CO 2 R 11 , --OCO 2 R 12 , --CON(R 11 ) 2 , --NR 11 C(═O)R 11 , --CN, alkyl, aryl, alkenyl and alkynyl, said alkyl group is optionally substituted with --OR 11 , --SR 11 , --N(R 11 ) 2 or --CO 2 R 11 , and said alkenyl group is optionally substituted with halo, --OR 12 or --CO 2 R 11 ;
adjacent R 1 and R 2 groups can optionally be taken together to form a benzene ring fused to the ring s;
adjacent R 3 and R 4 groups can optionally be taken together to form a benzene ring fused to the ring t;
R 5 and R 6 are each independently selected from the group consisting of: H, alkyl and aryl; or R 5 can be taken together with R 6 to represent ═O or ═S;
R 7 , R 8 and R 9 are each independently selected from the group consisting of: H, halo, --CF 3 , --OR 11 , --C(O)R 11 , --SR 11 , --S(O) e R 12 wherein e is 1 or 2, --N(R 11 ) 2 , --NO 2 , --CN, --CO 2 R 11 , --OCO 2 R 12 , --OC(O)R 11 , --CON(R 11 ) 2 , --NR 11 C(O)R 11 , alkyl, aryl, alkenyl and alkynyl, said alkyl group is optionally substituted with --OR 11 , --SR 11 , --N(R 11 ) 2 , or --CO 2 R 11 , and said alkenyl group is optionally substituted with halo, --OR 12 or --CO 2 R 11 ;
Q is selected from the group consisting of: ##STR19## wherein the dotted line between carbon atoms 5 and 6 represents an optional double bond, such that when a double bond is present, A and B are each independently selected from the group consisting of: -R 11 , --OR 12 , halo and --OC(O)R 11 , and when no double bond is present, A and B are each independently selected from the group consisting of: H 2 , --(OR 12 ) 2 , (alkyl and H), (alkyl) 2 , (--H and --OC(O)R 11 ), (H and --OR 11 ), ═O and ═NOR 10 ;
R 10 is selected from the group consisting of: H and alkyl;
R 11 is selected from the group consisting of: H, alkyl and aryl;
R 12 is selected from the group consisting of: alkyl and aryl; and
Z is selected from the group consisting of: O and S, or Z optionally represents H and R 10 .
In preferred compounds of Formula I, R 1 , R 2 , R 3 , and R 4 are each independently selected from the group consisting of: H, halo, --OR 11 , and alkyl, with H being most preferred; R 5 and R 6 are each independently selected from the group consisting of: H and alkyl, with H being most preferred; R 7 , R 8 , and R 9 are each independently selected from the group consisting of: H, halo, --OR 11 , and alkyl, with H being most preferred; Q is selected from the group consisting of: --O--, --S--, --NR 10 (wherein R 10 is most preferrably H or methyl), ##STR20## Z is selected from the group consisting of O, and H and R 10 wherein R 10 is preferably H; and L is N + O - .
Even more preferred compounds of this invention are represented by Formula IA: ##STR21## wherein the substituents are as defined above for Formula I.
Still more preferred compounds are those of Formula IA wherein: R 1 , R 2 , R 3 , and R 4 are each independently selected from the group consisting of: H, halo, --OR 11 , and alkyl, with H being most preferred; R 5 and R 6 are each independently selected from the group consisting of: H and alkyl, with H being most preferred; R 7 , R 8 , and R 9 are each independently selected from the group consisting of: H, halo, --OR 11 , and alkyl, with H being most preferred; Q is selected from the group consisting of: ##STR22## Z is selected from the group consisting of O, and H and R 10 wherein R 10 is preferably H; and L is N + O - .
Even more preferred compounds are those compounds of Formula IA wherein Q is selected from the group consisting of: --O--, --S--, ##STR23## (wherein R 10 is most preferrably methyl), and ##STR24##
Representative compounds of this invention include, but are not limited to: ##STR25##
This invention also provides a pharmaceutical composition comprising an effective amount of a compound of Formula I in combination with a pharmaceutically acceptable carrier.
This invention further provides a method for treating allergic reaction in a mammal comprising administering to the mammal an effective anti-allergic amount of a compound of Formula I.
Additionally, this invention provides a method for treating inflammation in a mammal comprising administering to the mammal an effective anti-inflammatory amount of a compound of Formula I.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, the following terms are used as defined below unless otherwise indicated:
alkyl--(including the alkyl portions of alkoxy, alkylamino and dialkylamino)--represents straight and branched carbon chains and contains from one to twenty carbon atoms, preferably one to six carbon atoms;
alkenyl--represents straight and branched carbon chains having at least one carbon to carbon double bond and containing from 2 to 12 carbon atoms, preferably from 2 to 6 carbon atoms;
alkynyl--represents straight and branched carbon chains having at least one carbon to carbon triple bond and containing from 2 to 12 carbon atoms, preferably from 2 to 6 carbon atoms;
aryl--represents a carbocyclic group (preferably phenyl or substituted phenyl) containing from 6 to 14 carbon atoms and having at least one phenyl or fused phenylene ring, with all available substitutable carbon atoms of the carbocyclic group being intended as possible points of attachment, said carbocyclic group being optionally substituted with one or more of halo, alkyl, hydroxy, alkoxy, phenoxy, cyano, cycloalkyl, alkenyloxy, alkynyloxy, --SH, --S(O) e R 12 (wherein e is 1 or 2 and R 12 is alkyl or aryl), --CF 3 , amino, alkylamino, dialkylamino, --COOR 12 or --NO 2 ; and
halo--represents fluoro, chloro, bromo and iodo.
Also, unless indicated otherwise, the following abbreviations used herein have the following meanings:
CDI--N,N'-carbonyldiimidazole;
DCC--N,N'-dicyclohexylcarbodiimide;
DEC--1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride;
eq--equivalents;
HOBT--1-hydroxybenzotriazole hydrate; and
THF--tetrahydrofuran.
Certain compounds of the invention may exist in different isomeric (e.g., enantiomers and diastereoisomers) as well as conformational forms. The invention contemplates all such isomers both in pure form and in admixture, including racemic mixtures. Enol forms are also included. For example, hydroxy substituted pyridinyl groups can also exists in their keto form: ##STR26##
The compounds of Formula I can exist in unsolvated as well as solvated forms, including hydrated forms, e.g., hemi-hydrate. In general, the solvated forms, with pharmaceutically acceptable solvents such as water, ethanol and the like are equivalent to the unsolvated forms for purposes of the invention.
As noted above, the pyridine and benzene ring structures of Formula I may contain one or more substituents R 1 , R 2 , R 3 and R 4 , and the pyridine ring containing L may contain one or more substituents R 7 , R 8 , and R 9 . In compounds where there is more than one substituent on a ring, the substituents may be the same or different. Thus compounds having combinations of such substituents are within the scope of the invention. Also, the lines drawn into the rings from the R 1 , R 2 , R 3 , R 4 , R 7 , R 8 , and R 9 groups indicate that such groups may be attached at any of the available positions. For example, the R 1 and R 2 groups may be attached to a carbon atom at any of the a, b, c or d positions.
R 5 and R 6 are attached to the piperidyl ring. As such they may be the same or different. The variables R 5 and R 6 in addition to representing H, may represent variables attached to the same or different carbon atoms in said ring. For example, when R 5 and R 6 are combined to represent ═O or ═S, they are attached to the same carbon atom.
The N-oxides are illustrated herein using the terms NO, N→O, N--O and N + O - . All are considered equivalent as used herein.
Lines drawn into the ring systems indicate that the indicated bond may be attached to any of the substitutable ring carbon atoms.
Certain compounds of the invention will be acidic in nature, e.g. those compounds which possess a carboxyl or phenolic hydroxyl group. These compounds may form pharmaceutically acceptable salts. Examples of such salts may include sodium, potassium, calcium, aluminum, gold and silver salts. Also contemplated are salts formed with pharmaceutically acceptable amines such as ammonia, alkyl amines, hydroxyalkylamines, N-methylglucamine and the like.
Certain basic compounds of the invention also form pharmaceutically acceptable salts, e.g., acid addition salts. For example, the pyrido-nitrogen atoms may form salts with strong acid, while compounds having basic substituents such as amino groups also form salts with weaker acids. Examples of suitable acids for salt formation are hydrochloric, sulfuric, phosphoric, acetic, citric, oxalic, malonic, salicylic, malic, fumaric, succinic, ascorbic, maleic, methanesulfonic and other mineral and carboxylic acids well known to those in the art. The salts are prepared by contacting the free base form with a sufficient amount of the desired acid to produce a salt in the conventional manner. The free base forms may be regenerated by treating the salt with a suitable dilute aqueous base solution such as dilute aqueous sodium hydroxide, potassium carbonate, ammonia and sodium bicarbonate. The free base forms differ from their respective salt forms somewhat in certain physical properties, such as solubility in polar solvents, but the acid and base salts are otherwise equivalent to their respective free base forms for purposes of the invention. All such acid and base salts are intended to be pharmaceutically acceptable salts within the scope of the invention and all acid and base salts are considered equivalent to the free forms of the corresponding compounds for purposes of the invention.
The following processes can be employed to produce compounds of Formula I (i.e., IA-IF). Those skilled in the art will recognize that the reactions are conducted under conditions, e.g., temperature, that will allow the reaction to proceed at a reasonable rate to completion. Also, unless indicated otherwise, the substituents for the formulas given hereinafter have the same definition as those of Formula I.
Process A--Compounds of Formula I wherein Z is O (oxygen) (i.e., IB) ##STR27##
A compound of Formula II can be reacted with a compound of Formula III to produce a compound of Formula IB wherein Z is O. In the preferred method, B is hydroxy and a coupling reagent is employed to produce compounds of Formula IB. The reaction can be conducted in an inert solvent, such as THF or methylene chloride (with methylene chloride usually being preferred), at a temperature of about -15° C. to reflux. Examples of coupling agents include DCC, DEC, and CDI.
If B represents a suitable leaving group other than hydroxy, for example a halide (such as Cl, Br, or I) or --O(CO)R 12 , then a suitable base is usually present. The reaction is usually conducted in an inert solvent, such as tetrahydrofuran (THF) or methylene chloride, and at a suitable temperature, such as a temperature of about -15° C. to reflux. Suitable bases include pyridine and triethylamine. The use of a base can often be omitted when the compound of Formula II contains a basic amine functionality (e.g., one of a, b, c, or d is nitrogen).
When B is alkoxy (--OR 12 ), compounds of Formula IB may be produced by refluxing a compound of Formula II with an excess of a compound of Formula III in an inert solvent such as THF, methylene chloride or toluene.
Process B--Compounds of Formula I wherein Z is H and R 10 (i.e., IC) ##STR28##
In the preferred method, a compound of Formula II can be reacted with a compound of Formula IIIA in the presence of a base to produce compounds of Formula IC wherein Z is H and R 10 . The reaction is usually conducted in an inert solvent such as THF or methylene chloride at a suitable temperature, usually at reflux, although lower temperatures can be employed, for example about 0° C. to reflux. Suitable bases include pyridine and triethylamine. The use of a base can be omitted when the compound of Formula II contains a basic amine functionality (e.g., either a, b, c, or d is nitrogen). B designates a suitable leaving group such as halo, (e.g., Br or Cl), mesyl, tosyl or the like.
Alternatively, the compounds of Formula IC may be prepared via reductive amination of the compound of Formula II with the pyridincarboxaldehyde of Formula IV: ##STR29##
The reaction can be carried out in a polar solvent, such as an alcohol (e.g., methanol or ethanol) with the optional use of a water scavenger, such as a 3 Å molecular sieve. The intermediate Schiff Base which is formed is reduced with H 2 in the presence of a Pd/C catalyst or a reducing agent, such as sodium cyanoborohydride (NaCNBH 3 ). The reaction takes place at a temperature of about 0° to about 100° C. based on the solvent used.
Compounds of Formula IC, wherein R 10 is H, may be prepared via reduction of the corresponding amides of Formula IB. Treatment of Formula IB with lithium aluminum hydride (LiAlH 4 ), or similar known reducing agents, reduces the carbonyl of Formula IB, thus, providing compounds of Formula IC wherein R 10 is H. The reaction is typically carried out in an inert solvent at a temperature of about 0° C. to reflux. Usually an etheral solvent such as THF or diethyl ether is used. This method is limited to cases where the reducing agent will not effect the reduction of other functional group such as esters and ketones.
Process C--Compounds of Formula I wherein Z is O and L is N (i.e., ID) ##STR30##
Compounds of Formula ID wherein, L is N, may be prepared directly by reacting a compound of Formula VIII with a compound of Formula IIIB. Preferably, the reaction can be run in the presence of a suitable nucleophile (e.g., LiI and the like) in an inert solvent, such as toluene, dioxane or xylenes. B in Formula IIIB is a suitable leaving group, such as halo (e.g., Br or Cl) or --OC(O)R 12 . A suitable base (such as K 2 CO 3 or Cs 2 CO 3 ) can be added and heating is usually required. Typically, a temperature of about 50° to about 300° C. (preferably about 100° to about 175° C.) can be utilized depending on the boiling point of the solvent.
Process D--Compounds of Formula I wherein Z is S and L is N (i.e., IE) ##STR31##
Compounds of Formula IE can be prepared by reacting a compound of Formula IB with P 2 S 5 , Lawesson's reagent or other suitable reagent known in the art for introducing sulfur in place of oxygen. The reaction can usually be conducted at an elevated temperature, such as about 80° to about 150° C. in a solvent such as pyridine, toluene (preferred) or xylene.
Process E--Compounds of Formula I wherein Z is O (oxygen) and L is NO (i.e., IF) ##STR32##
This may be accomplished with a suitable oxidizing agent in an inert solvent such as meta-chloroperbenzoic acid (MCPBA) in methylene chloride or hydrogen peroxide in acetic acid. The reaction is usually conducted at a temperature of about -15° C. to reflux. When present, oxidation of other basic amino groups in the molecule (e.g., --NH 2 , --N(CH 3 ) 2 and the like) can occur with this method; however, in such cases, with excess reagent the N-oxides of Formula IF can be produced. Compounds of Formula ID wherein L is nitrogen (L=N) are prepared as described in methods described in processes A and C.
Preparation of Intermediate Compounds ##STR33##
Compounds of Formula II can be prepared by removal of the carbamoyl moiety (COOR 13 ) wherein R 13 can be, for example alkyl, aryl or halogenated alkyl (e.g., trichloroethyl) from the corresponding carbamate of Formula V via either acid (e.g., HCl/H 2 O/heat) or base (e.g., KOH/ethanol/H 2 O/heat) hydrolysis. The reaction is usually carried out between about 80° C. to reflux depending on the solvent of choice.
Alternatively, depending upon the nature of R 13 , as determined by one skilled in the art, the compound of Formula V can be treated with an organometallic reagent (e.g., CH 3 Li for R 13 =CH 3 ), with a reductive reagent (e.g., Zn in acid for R 13 =CH 2 CCl 3 ), with an alcohol or water (e.g., for R 13 =CHClCH 3 ), or with hydrogen and a noble metal catalyst such as palladium on carbon (e.g., Pd/C and H 2 for R 13 =aralkyl such as benzyl, and the like) to form compounds of Formula II.
Compounds of Formula II can also be obtained from the corresponding nitrile of Formula VI: ##STR34## via either acid hydrolysis (e.g., HCl/H 2 O/heat (about 90° to about 100° C.)) or base hydrolysis (e.g. KOH/ethanol/H 2 O/heat (about 90° to about 100° C.)). The reaction can be conducted at reflux.
Compounds of Formula II can also be prepared from compounds of Formula VIIA wherein Q is O or S, and R 14 represents alkoxylcabonyl (for example, --C(O)OR 15 wherein R 15 represents an alkyl group having 1 to 6 carbons). Compounds of Formula II can also be prepared from compounds of Formula VIIB wherein Q is O or S, and R 14 represents --C(O)H. Both reactions can be carried out by treating compounds of Formulas VIIA or VIIB with concentrated HCl and water under reflux. ##STR35##
Compounds of Formula V can be prepared from the N-alkyl (preferably N-methyl) compounds of Formula VIII: ##STR36## by reacting the compound of Formula VIII with a suitable alkyl, aryl or halogenated alkyl (e.g., trichloroethyl) chloroformate to provide the desired carbamate (e.g., ethylchloroformate, using a temperature of about 50° C. to reflux, usually about 50° to about 90° C., in an inert solvent, such as toluene or benzene). The procedure is disclosed in U.S. Pat. No. 4,282,233, U.S. Pat. No. 4,355,036 and WO 88/03138, the disclosures of which are incorporated herein by reference thereto.
Compounds of Formula V can also be prepared by ##STR37## alkylation of the ketone of Formula IX with a compound of Formula X wherein R 12 represents an alkyl group containing 1 to 6 carbon atoms with ethyl being preferred, or aryl. The reaction can be conducted in an inert solvent such as THF or diethyl ether with liquid ammonia as a co-solvent in the presence of 2 equivalents of sodium metal.
Compounds of Formula X can be prepared from the 1-methyl-4-chloro-piperidine of Formula XI: ##STR38## by reaction with the appropriate alkyl or aryl chloroformate in an inert solvent (e.g., toluene) at a temperature of about 50° to about 120° C. This procedure is disclosed in U.S. Pat. No. 4,282,233, U.S. Pat. No. 4,355,036 and WO 88/03138, the disclosures of which having already been incorporated herein by reference thereto.
Compounds of Formula VI can be prepared from compounds of Formula VIII by the well known von Braun reaction (for example, J. V. Braun, Ber. 44, 1250 (1911)). For example, treatment of a compound of Formula VIII with cyanogen bromide (BrCN) in an inert solvent (e.g., toluene or benzene) at a temperature of about 50° to about 120° C. would provide the nitrile of Formula VI.
Compounds of Formula VIIA wherein Q is O or S and R 14 represents alkoxycarbonyl (e.g., --CO 2 C 2 H 5 or CO 2 CH 2 CCl 3 ) can be prepared from compounds of Formula XII: ##STR39## wherein R 10 is an alkyl group, preferably methyl, using the method disclosed above for the preparation of compounds of Formula V from the compounds of Formula VIII.
Compounds of Formula VIIB wherein Q is O or S, and R 14 represents a formyl (--CHO) group, can be prepared by treating compounds of Formula XII, wherein R 10 is H, with ethylformate as a solvent under reflux. Preferably, the reaction is continued overnight.
The compound of Formula XII ##STR40## can be prepared by refluxing the compound of Formula VIII in acetic acid in the presence of acetic anhydride and acetyl chloride for a period of 10 to 24 hours.
Compounds of Formula VIII can be prepared by treating the ketone of Formula IX with a Grignard reagent of Formula XIII: ##STR41## (wherein M is MgCl or Na) in an inert solvent, such as diethyl ether, benzene, or THF. Preferably, the N-alkyl group is a methyl group. The reaction can be conducted at a temperature of about 0° C. to about room temperature in an argon atmosphere. The reaction mixture can be quenched with NH 4 Cl to form the compound of Formula VIII. If sodium metal is used, liquid ammonia is used as a co-solvent.
The compound of Formula XIII can be prepared by procedures known in the art from magnesium and the 4-chloro N-substituted (preferably N-methyl) piperidine.
Those skilled in the art will appreciate that many of the substituents (R 1 -R 9 , A, and B) present in the various intermediates of the synthetic sequences described above can be used to generate different substituents by methods known to those skilled in the art. For example, a ketone can be converted to a thioketone via its treatment with P 2 S 5 or Lawesson's reagent. These reagents introduce sulfur in place of oxygen. The reaction may take place at room or higher temperatures in pyridine, toluene or other suitable solvents. A ketone can also be converted to an alkyl or aryl group. This is accomplished via treatment of the ketone with a Wittig reagent or other organometalic species (e.g., Grignard reagent) to produce the corresponding olefin or alcohol, respectively. These derivatives in turn can be converted to the alkyl or aryl compounds.
In the above processes, in accordance with procedures well known to those skilled in the art, it is sometimes desirable and/or necessary to protect certain groups during the reactions. Certain protecting groups are employed in the above processes but, as those skilled in the art will recognize, other protecting groups may be used in their place. Conventional protecting groups are operable as described in Greene, T. W., "Protective Groups In Organic Synthesis," John Wiley & Sons, New York, 1981; the disclosure of which is incorporated herein by reference thereto. After the reaction or reactions, the protecting groups can be removed by standard procedures.
The compounds of the invention possess platelet-activating factor ("PAF") antagonistic properties and are believed to have histamine antagonistic properties. The compounds of the invention are, therefore, useful when PAF and/or histamine are factors in the disease or disorder. This includes allergic diseases such as asthma, allergic rhinitis, adult respiratory distress syndrome, urticaria and inflammatory diseases such as rheumatoid arthritis and osteo-arthritis. For example, PAF is an important mediator of such processes as platelet aggregation, smooth muscle contraction (especially in lung tissue), eosinophil chemotxis, vascular permeability and neutrophil activation. Recent evidence implicates PAF as an underlying factor involved in airway hyperreactivity.
The PAF antagonistic properties of these compounds may be demonstrated by use of standard pharmacological testing procedures as described below. These test procedures are standard tests used to determine PAF antagonistic activity and to evaluate the usefulness of said compounds for counteracting the biological effects of PAF. The in vitro assay is a simple screening test, while the in vivo test mimics clinical use of PAF antagonists to provide data which simulates clinical use of the compounds described herein.
A. In Vitro Studies--Platelet Aggregation Assay
Platelet-activating factor (PAF) causes aggregation of platelets by a receptor-mediated mechanism. Therefore, PAF-induced platelet aggregation provides a simple and convenient assay to screen compounds for PAF antagonism.
Human blood (50 ml) was collected from healthy male donors in an anticoagulant solution (5 ml) containing sodium citrate (3.8%) and dextrose (2%). Blood was centriguged at 110×g for 15 min. and the supernatant platelet-rich plasma (PRP) carefully transferred into a polypropylene tube. Platelet-poor-plasma (PPP) was prepared by centrifuging PRP at 12,000×g for 2 min. (Beckman Microfuge B). PRP was used within 3 hr. of drawing the blood.
PAF was dissolved in chloroform:methanol (1:1, v/v) at a concentration of 2 mg/ml and stored at -70° C. An aliquot of this solution was transferred to a polypropylene tube and dried under a flow of nitrogen gas. To the dried sample was added Hepes-saline-BSA (BSA=bovine serum albumen) buffer (25 mM Hepes, pH 7.4, 1254 mM NaCl, 0.7 mM MgCl 2 and 0.1% BSA) to obtain a 1 mM solution and sonicated for 5 min. in a bath sonicator. This stock solution was further diluted to appropriate concentrations in Hepes-saline-BSA buffer. Collagen (Sigma) and adenosine diphosphate (ADP) (Sigma) were purchased as solutions. Test compounds were initially dissolved in dimethyl sulfoxide (DMSO) at a concentration of 50 mM and then further diluted in Hepes-saline-BSA buffer to achieve appropriate concentrations.
When an aggregating agent such as PAF is added to PRP, platelets aggregate. An aggregometer quantifies this aggregation by measuring and comparing light (infra-red) transmission through PPP and PRP. Aggregation assays were performed using a dual-channel aggregometer (Model 440, Chrono-Log Corp., Havertown, Pa.). PRP (0.45 ml) in aggregometer cuvettes was continually stirred (37° C.). Solutions (50 μL) of test compounds or vehicel were added to the PRP and, after incubation for 2 min., 10-15 μl aliquots of PAF solution were added to achieve a final concentration of 1-5×10 -8 M. In different experiments the aggreatory response was kept within a set limit by varying the concentration of PAF. Incubations were continued until the increase in light transmission reached a maximum (usually 2 min.). This increase in light transmission reflecting platlet aggregation is transmitted to a computer by the Chrono-Log model 810 AGGRO/LINK interface. The AGGRO/LINK calculates the slope of transmission change, thus providing the rate of aggregation. Values for inhibition were calculated by comparing rates of aggregation obtained in the absence and the presence of the compound. For each experiment, a standard PAF antagonist such as 8-chloro-6,11-dihydro-11-(1-acetyl-4-piperidylidene)-5H-benzo[5,6]cyclohepta[1,2-b]pyridine was used as a positive control.
Compounds that inhibit PAF-induced aggregation were tested against several other aggregating agents including collagen (0.2 mg/ml) and ADP (2 μM). Compounds showing no activity against these latter agents were considered to be specific PAF antagonists. Results are shown in TABLE 1 below.
B. In Vivo Studies: Agonist-Induced Responses--Spasmogen-Induced Bronchospasm in Guinea Pigs
Male Hartley guinea pigs (450-550 g) were obtained from Charles River Breeding Laboratories. The animals were fasted overnight and the following day were anesthetized with 0.9 ml/kg i.p. of dialurethane (containing 0.1 g/ml diallylbarbituric acid, 0.4 g/ml ethylurea and 0.4 g/ml urethane). The left jugular vein was cannulated for the administration of compounds. The trachea was cannulated and the animals were ventilated by a rodent respirator at 55 strokes/min. with a stroke volume of 4 ml. A side arm to the tracheal cannula was connected to a pressure transducer to obtain a continuous measure of inflation pressure. Bronchoconstriction was measured as the percent increase in inflation pressure that peaked within 5 min. after challenge with spasmogen. The animals were challenged i.v. with either histamine (10 ug/kg), methacholine (10 μg/kg), 5-hydroxytryptamine (10 μg/kg), or PAF (0.4 μg/kg in isotonic saline containing 0.25% BSA). Each animal was challenged with only a single spasmogen. The effect of a compound on the bronchospasm is expressed as a percent inhibition of the increase in inflation pressure compared to the increase in a control group. Results are shown in TABLE 1 below.
TABLE 1______________________________________PAF Agonist Bronchospasm (in Vivo)-oralAntagonism PAF HistamineCMPD (in vitro) % %NO IC.sub.50 (μM) Dose Inhibition Dose Inhibition______________________________________IA-1 5.0 -- -- -- --IA-2 5.0 -- -- -- --IA-3 2.0 3 mpk 97 3 mpk 0IA-4 0.8 -- -- -- --IA-5 5.0 3 mpk 7 -- --IA-6 1.5 3 mpk 20 -- --IA-8 2 3 mpk 25 -- --IA-9 >10 -- -- -- --IA-10 10 -- -- -- --IA-11 5.0 -- -- -- --IA-12 3.0 3 mpk 42 3 mpk 0IA-14 1.75 -- -- -- --______________________________________
For preparing pharmaceutical compositions from the compounds described by this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets and suppositories. The powders and tablets may be comprised of from about 5 to about 70 percent active ingredient. Suitable solid carriers are known in the art, e.g. magnesium carbonate, magnesium stearate, talc, sugar, lactose. Tablets, powders, cachets and capsules can be used as solid dosage forms suitable for oral administration.
For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides or cocoa butter is first melted, and the active ingredient is dispersed homogeneously therein as by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool and thereby solidify.
Liquid form preparations include solutions, suspensions and emulsions. As an example may be mentioned water or water-propylene glycol solutions for parenteral injection.
Liquid form preparations may also include solutions for intranasal administration.
Aerosol preparations suitable for inhalation may include solutions and solids in powder form, which may be in combination with a pharmaceutically acceptable carrier, such as an inert compressed gas.
Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions and emulsions.
The compounds of the invention may also be deliverable transdermally. The transdermal compositions can take the form of creams, lotions, aerosols and/or emulsions and can be included in a transdermal patch of the matrix or reservoir type as are conventional in the art for this purpose.
Preferably the compound is administered orally.
Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component, e.g., an effective amount to achieve the desired purpose.
The quantity of active compound in a unit dose of preparation may be varied or adjusted from about 0.1 mg to 1000 mg, more preferably from about 1 mg. to 300 mg, according to the particular application. The appropriate dosage can be determined by comparing the activity of the compound with the activity of a known PAF and histamine antagonist such as 8-chloro-6,11-dihydro-11-(1-acetyl-4-piperidylidene)-5H-benzo[5,6]cyclohepta[1,2-b]pyridine, which compound is disclosed in U.S. Pat. No. 4,826,853.
The actual dosage employed may be varied depending upon the requirements of the patient and the severity of the condition being treated. Determination of the proper dosage for a particular situation is within the skill of the art. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired.
The amount and frequency of administration of the compounds of the invention and the pharmaceutically acceptable salts thereof will be regulated according to the judgment of the attending clinician considering such factors as age, condition and size of the patient as well as severity of the symptoms being treated. A typical recommended dosage regimen is oral administration of from 10 mg to 1500 mg/day preferably 10 to 1000 mg/day, in two to four divided doses to achieve relief of the symptoms. The compounds are non-toxic when administered within this dosage range.
The invention disclosed herein is exemplified by the following preparative examples, which should not be construed to limit the scope of the disclosure. Alternative mechanistic pathways and analogous structures within the scope of the invention may be apparent to those skilled in the art.
PREPARATIVE EXAMPLE 1 ##STR42##
To a cool (ice/H 2 O bath) solution of xanthone (4.0 g in THF (60 mL), Formula 1.0, was added a 1.2M solution of N-methyl 4-piperidyl magnesium chloride (20 mL). The reaction was allowed to stir for 1 hour while warming to room temperature. The reddish reaction mixture was then poured into ice water, followed by quenching with a saturated ammonium chloride solution. The white precipitated product was filtered to give 5.0 g (83% yield) of the compound of Formula 2.0. ##STR43##
To a hot solution (in a 80°-90° C. oil bath) of compound 2.0 (2.2 g) and triethylamine (3.12 mL, 3.0 eq.) in toluene (35 mL) was added ethylchloroformate (3.57 mL, 50 eq.) dropwise in 20 minutes. The reaction was heated at this temperature for about 1.5 hours or until no starting material could be detected by TLC (developing solvent: 50% ethyl acetate in hexane). The reaction was then cooled and diluted with ethyl acetate. The resulting reaction mixture was then washed once with water, once with brine, and then dried (Na 2 SO 4 ). The reaction mixture was then filtered and the solvent was removed under vacuum on a rotory evaporator. The crude product was purified by chromatography on silica gel (eluted with 25% ethyl acetate in hexanes), and then recrystallized from acetone and pentane to give the compound of Formula 3.0, 1.71 g (66% yield), m.p. 142°-144° C. as a white crystalline solid. ##STR44##
The compound of Formula 3.0 (0.55 g) was hydrolyzed in concentrated hydrochloric acid and water (70:30 by volume, 50 mL) by heating the solution in an oil bath (100° C.) for 8 hours followed by stirring at room temperature for overnight. The reaction mixture was poured into ice/water and then basified to pH 8-9 with a 25% NaOH solution. Then the reaction mixture was extracted with CH 2 Cl 2 , dried (Na 2 SO 4 ) and filtered. The solvent was removed on a rotory evaporator under vacuum and the product was recrystallized from methanol and CH 2 Cl 2 to give the compound of Formula 4.0, 0.223 g (51% yield), m.p. 237-238, as an off-white solid.
By utilizing the starting materials, Formulas 5.0, 7.0, and 9.0 listed in Table 2 below, and employing procedures similar to that described in Steps A to C of Preparative Example 1, then the compounds of Formulas 6.0, 8.0 and 10.0, respectively were prepared.
TABLE 2__________________________________________________________________________Starting Material Product m.p.__________________________________________________________________________ ##STR45## ##STR46## 112-114° C. ##STR47## ##STR48## -- ##STR49## ##STR50## --__________________________________________________________________________
PREPARATIVE EXAMPLE 2 ##STR51##
To a cool (ice/H 2 O bath) solution of thioxanthen-9-one, Formula 11.0, (4.0 g) in THF (60 mL) was added a 1.2M solution of N-methyl-4-piperidyl magnesium chloride (40 mL). The ice bath was removed and the reaction mixture was stirred for 30 minutes at room temperature, and then the reaction was quenched with NH 4 Cl solution. The reaction mixture was extracted with ethyl acetate and washed once with brine and then dried (Na 2 SO 4 ). The reaction mixture was then filtered and the solvent was removed under vacuum to give a crude product. The crude product was recrystallized from ethyl acetate and diisopropyl ether (80:20)to give the compound of Formula 12.0, 4.35 g, as a solid. ##STR52##
To a hot solution (in a 95° C. oil bath) of the compound of Formula 12.0, (2.0 g) and triethylamine (2.52 mL, 2.8 eq) in toluene (40 mL) was added 2,2,2-trichloroethylchlorofomate (6.6 mL 7.5 eq) dropwise in 25 minutes. The reaction mixture was heated at this temperature for 1 hour and then cooled and diluted with ethyl acetate. The reaction mixture was then washed once with water, once with brine and then dried (Na 2 SO 4 ). The reaction mixture was then filtered and the solvent was removed. The compound of Formula 13.0, 1.64 g, was obtained as a tan powder. ##STR53##
A mixture of the compound of Formula 13.0, (0.56 g), and zinc dust (1.5 g) in glacial acetic acid (22 mL) was heated in an oil bath (70° C.) for 2 hours. The reaction mixture was cooled and then filtered. The acetic acid was removed on a rotory evaporator with a mechanical pump and the residue was basified to pH=8 with a 6N NaOH solution. This mixture was then extracted with CH 2 Cl 2 , and the CH 2 Cl 2 was then washed once with brine and then dried (Na 2 SO 4 ). The mixture was then filtered and the solvent was removed on a rotory evaporator with vacuum to give the compound of Formula 14.0, 238 mg, as a solid.
The compound of Formula 15.0 used in the procedures similar to those described in steps A through C of Preparative Example 2, produced the compound of Formula 16.0: ##STR54##
PREPARATIVE EXAMPLE 3 ##STR55##
To a solution of sodium metal (3.0 g) in 500 mL anhydrous liquid ammonia was added a suspension of a compound of Formula 17.0 (11.8 g) in THF (250 mL). This mixture was stirred for 1 hour and then a solution of N-methyl-4-chloropiperidine (8.0 g) in THF (250 mL) was dripped in. The reaction mixture was stirred for 2.5 hours. Solid NH 4 Cl and water were slowly added sequentially to the reaction mixture. The mixture was extracted with CHCl 3 . The extract (CHCl 3 layer) was washed with water and then dried (Na 2 SO 4 ). The solvent was removed with vacuum on a rotory evaporator and the resulting product was recrystallized from CH 3 CN to give the compound of Formula 18.0, 12.3 g, m.p. 155°-157° C. ##STR56##
To a hot solution (in a 90° C. oil bath) of the compound of Formula 18.0 (3.0 g) and triethylamine (3.82 mL) in dry toluene (50 mL) was added ethylchloroformate (9.56 mL) dropwise in 40 minutes. The reaction mixture was stirred continuously for 2 hours at this temperature. The reaction mixture was then cooled and then diluted with ethyl acetate. It was washed once with a 0.5N NaOH solution, once with brine and then dried (Na 2 SO 4 ). The mixture was filtered and the solvent was removed via vacuum. The resulting product was chromatographed on silica gel (eluted with 50% ethyl acetate in hexane) to give the compound of Formula 19.0, 2.2 g, as an off-white solid. ##STR57##
To a solution of the compound of Formula 19.0 (1.01 g) in ethanol (30 mL) was added a solution of KOH (1.5 g) in water (30 mL). The reaction mixture was refluxed for 21 hours. After cooling, it was diluted with CH 2 Cl 2 , washed with water and then dried (Na 2 SO 4 ). The mixture was then filtered and the solvent was removed with vacuum on a rotory evaporator to give the compound of Formula 20.0, 0.643 g, m.p. 233°-236° C.
PREPARATIVE EXAMPLE 4 ##STR58##
The compound of Formula 22.0 was obtained when the compound of Formula 21.0 was used in a procedure similar to that described in Step A of Preparative Example 3. ##STR59##
To a solution of BrCN (12.4 g) in CH 2 Cl 2 (50 mL) was added a compound of Formula 22.0 (20.0 g in 200 mL of methylene chloride). The reaction mixture was stirred overnight at room temperature and then washed with 10% HCl solution. The acidic aqueous layer was separated and then basified with 50% NaOH solution. The basified aqueous layer was extracted with CHCl 3 , dried (MgSO 4 ), filtered and the solvent was removed to give 11.3 g (solids) of Formula 23.0. ##STR60##
The compound of Formula 24.0 was obtained by using the compound of Formula 23.0 in a procedure similar to that described in Step C of Preparative Example 3.
EXAMPLE 1 ##STR61##
To a mixture of 190 mg (0.68 mmol) of the compound of Formula 20.0 and 113 mg (0.81 mmol) of isonicotinic acid N-oxide in 25 mL of dry methylene chloride at ice bath temperature, and under an argon atmosphere, was added 197 mg (1.02 mmol) of DEC and 138 mg (1.02 mmol) of HOBT. The ice bath was removed after 15 minutes and the reaction mixture was allowed to stir for 3 hours at room temperature. The reaction mixture was diluted with methylene chloride and washed once with aqueous NaHCO 3 (0.5M) and once with brine and then dried with Na 2 SO 4 . This mixture was then filtered and the solvent was removed under vacuum. The product was purified via a flash silica gel (230-440 mesh) column, eluting with 5% methanol saturated with ammonia in methylene chloride to give 147 mg of the compound of Formula IA-1 as white solids: m.p. 249°-250° C., MS (FAB) M/Z 404 (M + +1).
In a similar manner, the compounds of Table 3 below were prepared utilizing the indicated starting material.
TABLE 3__________________________________________________________________________EX No.Starting Material Final Product Physical Data__________________________________________________________________________ ##STR62## ##STR63## ##STR64##3 ##STR65## ##STR66## ##STR67##4 ##STR68## ##STR69## ##STR70##5 ##STR71## ##STR72## ##STR73##6 ##STR74## ##STR75## ##STR76##7 ##STR77## ##STR78## ##STR79##8 ##STR80## ##STR81## ##STR82##__________________________________________________________________________
EXAMPLE 9 ##STR83##
To a solution of carbontetrabromide (319 mg, 0.96 mmol) and 4-pyridylcarbinol N-oxide (119 mg, 0.96 mmol) in 10 mL of methylene chloride at room temperature was added triphenylphosphine, 252 mg (0.96 mmol). This mixture was stirred at room temperature for one hour, and then 160 mg (0.57 mmol) of the compound of Formula 20.0 was added followed by addition of 0.134 mL (0.96 mmol) of triethylamine. The reaction mixture was stirred at ambient temperature and under argon for two hours. It was then diluted with 300 mL of methylene chloride and then washed once with aqueous K 2 CO 3 (0.5M), once with brine and then dried with Na 2 SO 4 . After filtration the solvent was removed under vacuum and the crude product was chromatographed with silica gel (230-400 mesh), eluting with 5% methanol saturated with ammonia in CH 2 Cl 2 to give 167 mg of the compound of Formula IA-9 as an off-white glassy solid. MS (FAB) M/Z 390 (M + +1).
In a similar manner, the compounds of Table 4 below were prepared utilizing the indicated starting material.
TABLE 4__________________________________________________________________________EX No.Starting Material Final Product Physical Data__________________________________________________________________________10 ##STR84## ##STR85## ##STR86##11 ##STR87## ##STR88## ##STR89##12 ##STR90## ##STR91## ##STR92##13 ##STR93## ##STR94## ##STR95##14 ##STR96## ##STR97## ##STR98##__________________________________________________________________________
The following are examples of pharmaceutical dosage forms which contain a compound of the invention. As used therein, the term "active compound" is used to designate the compound
______________________________________No. Ingredients mg/tablet mg/tablet______________________________________1. Active compound 100 5002. Lactose USP 122 1133. Corn Starch, Food Grade, 30 40 as a 10% paste in Purified Water4. Corn Starch, Food Grade 45 405. Magnesium Stearate 3 7 Total 300 700______________________________________
The scope of the invention in its pharmaceutical composition aspect is not to be limited by the examples provided, since any other compound of Formula I can be substituted into the pharmaceutical composition examples.
Pharmaceutical Dosage Form Examples
EXAMPLE A
Tablets
______________________________________No. Ingredients mg/tablet mg/tablet______________________________________1. Active compound 100 5002. Lactose USP 122 1133. Corn Starch, Food Grade, 30 40 as a 10% paste in Purified Water4. Corn Starch, Food Grade 45 405. Magnesium Stearate 3 7 Total 300 700______________________________________
Method of Manufacture
Mix Item Nos. 1 and 2 in a suitable mixer for 10-15 minutes. Granulate the mixture with Item No. 3. Mill the damp granules through a coarse screen (e.g., 1/4", 0.63 cm) if necessary. Dry the damp granules. Screen the dried granules if necessary and mix with Item No. 4 and mix for 10-15 minutes. Add Item No. 5 and mix for 1-3 minutes. Compress the mixture to appropriate size and weigh on a suitable tablet machine.
EXAMPLE B
Capsules
______________________________________No. Inqredient mg/capsule mg/cagsule______________________________________1. Active compound 100 5002. Lactose USP 106 1233. Corn Starch, Food Grade 40 704. Magnesium Stearate NF 7 7 Total 253 700______________________________________
Method of Manufacture
Mix Item Nos. 1, 2 and 3 in a suitable blender for 10-15 minutes. Add Item No. 4 and mix for 1-3 minutes. Fill the mixture into suitable two-piece hard gelatin capsules on a suitable encapsulating machine.
While the present invention has been described in conjunction with the specific embodiments set forth above, many alternatives, modifications and variations thereof will be apparent to those of ordinary skill in the art. All such alternatives, modifications and variations are intended to fall within the spirit and scope of the present invention. | The invention is drawn to bridged bis-aryl carbinol compounds of formula (I): ##STR1## wherein, a, b, c, d, Q, Z, L and R 1 -R 9 are as defined in the specification, their pharmaceutical composition and method of using them in treating asthma, allergy and inflammation. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to cargo handling and particularly to the horizontal movement of cargo containers and pallets, in various directions, over the floor of an aircraft; and wherein retractable power driven wheels or tires are raised for engaging the undersurface of the cargo containers and pallets.
2. Description of the Prior Art
The subject matter of this application is related to the subject matter of U.S. Pat. No. 3,978,975 by Herbes et al issued Sept. 7, 1976. The patented power drive unit uses a double cam arrangement, wherein, one of the cams is fixedly mounted to airplane structure. Tolerance control between the interface of the power drive unit and mating hardware mounted on airplane structure results in functional reliability problems and difficulty in adjusting the mating hardware.
The device defined by this application is a self-contained mechanism of modular construction, that is designed to be inserted into an annular opening in the floor of the airplane, with the only airplane interface requirement being a torque reaction fitting and an electrical connection.
SUMMARY OF THE INVENTION
The invention relates to the handling of containerized cargo and cargo pallets, and more particularly to a power drive unit capable of maneuvering cargo along the floor, such as the floor of an aircraft. A powered wheel or roller makes frictional engagement with the underside of the cargo and through a steering mechanism which functions to change the direction of cargo movement, the cargo can be loaded laterally through the side-door entrance of an airplane fuselage and then moved longitudinally within the cargo compartment.
The power drive unit is a self contained unit that can be removed for bench adjustment of limit switches and maintenance; and this improves the airplane down time caused by interface and tolerance control problems.
An advantage of the invention is its unique modular feature that permits it to be dropped into a mating ringed hole in the floor, with a simple static interface with airplane structure and this minimizes dynamic operational problems.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1, is an isometric view of the powered wheel drive unit of the present invention, shown in an exploded arrangement and with respect to its mounting into floor structure.
FIG. 2, is a plan view of the powered wheel drive unit.
FIG. 3, is a side elevation view taken in the direction indicated by 3--3 of FIG. 2.
FIG. 4, is a developed flat view of one of the typical cam track profiles.
FIG. 5, is a side elevation view taken in the direction indicated by 5--5 of FIG. 2.
FIG. 6, is a side elevation schematic view of a limit switch taken in the direction indicated by 6--6 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 3 show in detail the components of the Power Drive Unit (PDU) assembly of this invention which engages the undersurface of containerized cargo and cargo pallets for moving the cargo in various directions. A roller or wheel 10 is mounted in a support housing or inner ring 11; and the wheel 10 is rotatably driven by a motor 12 through right-angle gearing 13.
To accommodate wheel height differences, the wheel 10 is mounted to the inner ring 11 through wheel bearings 14 and a vertical height adjustment plate 15 which is fastened by bolts 16 to inner ring 11. This arrangement permits vertical height adjustment of the wheel 10 above the top plane of caster rollers 17, thereby controlling the amount that a tire print or wheel 10 frictionally engages cargo undersurface.
The inner ring 11, which carries the wheel 10 and its drive motor 12, has a series of three cam follower bearings or rollers 18 arrange symmetrically around its outer periphery. The inner ring 11 is insertingly mated or interfaces with a stationary outer flanged ring 20 having a series of three alike cam profiles 21 arranged symmetrically around on its inner periphery; and each of the cam tracks or profiles 21 is engaged by a cam follower roller 18 of the inner ring 11. The cam tracks or profiles 21 are slots cut part way into the inner peripheral wall of the outer ring 20, i.e., the cam slots are not cut all the way through the wall thickness of the outer ring 20. The outer ring 20 also has a ring gear segment 22 fixedly fastened through bolts 23, to the skirt thereof. The ring gear segment 22 is engaged by a pinion gear 24 which is driven by motor 25 mounted through bolts 26 to the skirt of the inner ring 11.
Referring to FIG. 1, when the inner ring 11 is assembled into and mated with the outer ring 20, the pinion gear 24 engages ring gear segment 22 for rotatably driving the inner ring 11 relative to the outer ring 20.
When the outer ring 20 is vertically lowered into a mating ring support 28 in the floor opening, the tangs 29 on the outer ring 20 are inserted into slots 30 of the mating ring support 28 for reacting the torque of outer ring 20 thereby maintaining it stationary.
The PDU is generally installed in combination with a whole series of caster rollers 17 adjacent thereto, for supporting a major portion of the cargo load. The height of the wheel 10 above the cargo deck or top of the caster roller plane, in the raised position, is determined by both the vertical height adjustment plate 15 shown in FIG. 3 and the cam profile shown in FIG. 4.
FIG. 4 is a developed layout of the cam track profile which functions to vary the vertical height of the wheel 10 as the directional orientation of the wheel 10 about a vertical axis is changed. The sequential operation of the PDU from directional orientation points A through E, shown in the cam track profile of FIG. 4, will be described with reference to the figures and related to the operation of the PDU for moving a cargo container laterally, such as through a side doorway opening in the fuselage of an airplane, and then longitudinally within the fuselage.
Since the cam followers 18 are fixed to the inner ring 11, which also serves as the housing for the wheel 10, the movement of the cam followers in a horizontal plane from cam track profile points A to E, represents a 90° (ninety degree) steering change or change in the directional drive alignment of the wheel 10. The movement of the wheel 10 in a vertical plane is directly related to the vertical movement of the cam followers 18 in the cam track profile.
Assume that the fully raised position of the wheel 10, shown in FIGS. 1, 2, and 3, represents the initial position A of the cam track profile shown in FIG. 4, and also represents the directional drive alignment of the wheel 10 in the entry area of the side doorway of the airplane fuselage for moving the cargo container laterally, either into or out of fuselage cargo compartment, depending upon the direction of drive wheel rotation. The fully raised position of the wheel 10 places the top of the wheel, shown in FIG. 3, approximately 0.7 inches above the top of the caster roller plane and depending upon wheel size and tire inflation pressure, would be capable of applying a vertical load of approximately 2,000 lbs. when the wheel is depressed to the top plane of the caster rollers.
Initial directional realignment movement of the wheel 10 from cam track profile point A to point B, representing an arc of approximately 28°, is accomplished by pinion gear 24 reacting with fixed gear segment 22 which results in a rotational movement of inner ring 11 relative to the stationary outer ring 20. This causes the cam follower to move along the cam profile from points A to B resulting in a controlled linear lowering of the wheel of approximately 0.3 inch; whereat, the top of the tire, in an unloaded condition, would be approximately 0.4 inches above the top plane of the caster rollers 17.
Continued motion of the cam follower along the cam track profile from point B to C, which represents an arc of approximately 17°, results in directional alignment of the wheel 10 towards a 45° position; and due to a steep downwardly sloping cam track profile from point B to C, the wheel decends rapidly to its maximum lowered position, at which it has dropped a total vertical distance of 1.2 inches from its initial position at point A. At point C, the top of the wheel 10 is approximately 0.5 inches below the top of the caster roller plane; thereby, leaving the cargo container fully supported on the caster rollers for manual handling thereof. This cargo disengagement position at point C of 45° allows a symmetrical cam profile which results in symmetrical steering forces on either side of the tire unloaded position at point C. Therefore, due to the symmetrical cam design, the continued movement of the cam follower from the 45° position at point C, through point D, towards the 90° position at point E, will result in a reversal of the operation thus far described. At position E of the cam track profile, the wheel 10 is at a fully raised position and the drive alignment of the wheel is such that the cargo container can be moved longitudinally within the fuselage.
The 90° arc of directional alignment of the wheel 10 and its vertical travel, is regulated by the horizontal length and profile of the cam track; and this can be changed by redesigning the slot length and its cam profile.
Referring to FIGS. 1 and 3, the overall vertical length of pinion gear 24 or its gear width, is such as to accommodate the vertical motion of the inner ring 11 relative to the stationary outer ring 20, while maintaining a gear meshing relationship with the outer ring gear segment 22, throughout the directional alignment cycle of the wheel 10. During this 90° directional change of the wheel 10, the meshing engagement of the pinion gear 24 to the ring gear segment 22, undergoes a combination of: rolling involute contact, which is typical for any spur gear mesh; and an axial sliding contact, which is dictated by the shape of the cam slot 21 cut into the inner wall of the outer ring 20. This unique action allows the wheel steering load reactions to be completely contained within the PDU envelope, thus avoiding external load path support structure for the steering motor; thereby, providing an improved structural efficiency from the standpoint of overall system weight and stiffness. Torsional loads generated during the steering mode, are transmitted into cargo deck floor fittings by the tangs 29 mounted on the outer ring 20. Horizontal loads generated by the powered drive wheel 10 during movement of cargo containers or pallets, are carried by the bearing surfaces formed between the close fitting of the inner ring 11 and the outer ring 20, and then into floor structure. This close fitting relationship also controls the gear engagement or meshing relationship between the pinion gear 24 and the ring gear segment 22. Vertical loads of the PDU are carried between the inner rignt 11 and the outer ring 20, through the three cam rollers 18 equally spaced and mounted to the inner ring 11, which rollers mate with the three cam slots 21 cut into the outer ring 20.
Referring to FIGS. 5 and 6, limit switches 32, 33, and 34, are independently mounted within the PDU module for controlling the angular position logic and directional alignment in a horizontal plane of the drive wheel 10. Two of the limit switches 32 and 33, are mounted to the housing of the pinion gear drive motor or steering motor 25, for controlling the 0° and 90° positions of the wheel 10. The limit switches 32 and 33, are spaced apart on either side of the pinion gear 24 and are actuated when they engage projections or cam lobes 35, 36 mounted to the underside or skirt of the ring gear segment 22. The 1.2 inch vertical motion of the steering motor 25 which occurs during a 90° excursion of the inner ring 11, ensures that switch 32 has clearance with cam lobe 35 and switch 33 has clearance with cam lobe 36.
A third limit switch 34, shown in FIG. 6, is mounted on a bracket on the underside or skirt of the outer ring 20, for controlling the 45° position of the wheel 10. Limit switch 34 is actuated by the vertical motion of the inner ring 11 which reaches its lowest point at the 45° position.
Interface tolerance control problems are generally caused by PDU's, such as shown in U.S. Pat. No. 3,978,975, wherein the wheel alignment limit switches are mounted to fixed airplane structure and their adjustment is made with the PDU inserted into a mating ring support in the floor of the airplane. This also causes a functional reliability problem due to the difficulty in adjusting the individual limit switch settings.
Whereas, in the present invention, the switching logic for controlling the angular position or directional alignment of the wheel 10, is contained entirely within the PDU module and adjustment of the limit switches 32, 33, and 34 is accomplished with the PDU module completely removed and adjusted on the bench; thereby, eliminating the prior known interface problems associated with adjusting each individual limit switch mounted to fixed airplane structure. | A floor mounted power drive unit for moving containerized cargo or pallets within a cargo airplane; and the cargo drive unit generally comprises, a rotatable wheel or roller which is both steerable and retractable, and which is of modular construction for ease of insertion into a mounting opening in the floor of the cargo compartment with the only interface being a torque reaction means and an electrical connection. | 1 |
FIELD OF THE INVENTION
The invention relates to a disposal device for disposal of messy items such as pet excrement, food, or vomit. More generally, the invention relates to a disposal device for disposal of messy dirt for which a dustpan and brush, vacuum cleaner, or other conventional disposal devices are not suitable.
PRIOR ART DISCUSSION
Heretofore, some such disposal devices have been proposed. German Specification No. DE 3912972 describes such a device. The device comprises a bag and a scraper attached to the top end of the bag. The scraper is turned inside the bag together with the dirt. While this arrangement does provide a means to assist in picking up the dirt, it appears that such a device would be awkward to use and the dirt would not be cleanly picked, and it would therefore not gain widespread acceptance in the marketplace. German Specification No. DE 2836568 describes a device having a bag, a scraper, and an adhesive strip. The adhesive strip is adhered to the surface such as a pavement to assist in scraping the dirt. It appears that this device would also be awkward to use, and there are many situations in which the surface would not be suitable for adherence of the strip. PCT Specification No. WO 92/08345 describes a device in which a pair of blades are pressed against sides of a bag and the bag sides are subsequently turned inside out to leave the blades on the outside. Because the blades do not contact the dirt, they remain clean. It appears that this arrangement would also be awkward to use, and it also comprises a number of parts, which adds to production expense.
PCT Specification No. WO 98/01375 describes a device in which a scissors-type arrangement is used in conjunction with a bag. This arrangement appears to be complex because of the need for an operating mechanism, and it also appears to be quite bulky.
German Specification No. DE 3326305 describes a device which is an assembly of a bag and separate blades. The blades are inserted through slits in the bag from the outside. The assembly is placed directly over the dirt and the blades are rotated around into the bag until the leading edges are within the bag and the trailing ends protrude out from the bag mouth. It appears that use of this device would be awkward because the dirt is not visible as it is being picked. Also, the device is not compact and convenient to carry because it initially comprises three separate parts and, after use, the blades protrude from the bag in a bulky manner. European and German Specification Nos. DE 2935502 and EP 351600 both describe devices in which a strengthened rim is used to scrape the dirt into the bag. It appears that such an action is awkward and it would be difficult to keep one's hands and the bag external surfaces completely clean. PCT Specification No. WO 94/09212 describes a bag having a triangular reinforced mouth rim. Again, it appears that it would be difficult to effectively pick all of the dirt while keeping one's hands and the external surface of the bag clean.
Therefore, while many devices have been proposed addressing the same problem as the present invention, none of them are entirely satisfactory.
OBJECTS OF THE INVENTION
The invention is directed towards providing a disposal device which provides;
compact construction for ease of carrying devices available for use, for example, when walking a dog, or in a vehicle,
ease of use, whereby the user can quickly and conveniently pick dirt without getting his or her hands or the external surface dirty, and
simple construction, for low cost manufacture.
SUMMARY
According to the invention, there is provided a disposal device comprising:
a bag comprising:
least two walls, each having an inner surface and an outer surface, and
a bag mouth; and
a scraper connected to the bag, wherein:
the scraper is connected to a first bag wall at the inner surface of said bag wall, and
the device further comprises a scooper connected to a second bag wail at the inner surface of said bag wall.
By providing a scraper and a scooper connected in this manner, the invention allows the user to pick dirt in a manner similar to the action with a dustpan and brush. This is a simple and natural action, and allows the user to easily avoid getting his or her hands dirty.
In one embodiment, the scraper is connected to the first bag wall by a chute of flexible material. This allows easy and simple delivery of din into the bag.
In one embodiment, the chute has a width approximately equal to that of the scraper. In one embodiment, the first bag wall and the scraper chute are of plastics material, and the scraper chute is connected to the first bag wall by a heat seal.
In another embodiment, the scooper is connected to the second bag wall by a chute of flexible material. This allows simple and easy delivery of dirt into the bag. Preferably, the chute has a width approximately equal to that of the scooper blade.
In one embodiment, the scraper comprises an integral handle, and preferably, the scraper handle extends from a central portion of a scraper blade. This provides simplicity.
In another embodiment, the scooper comprises an integral handle and preferably, the scooper handle extends transversely of a scooper blade.
In one embodiment, the device further comprises a tab connected to a bag wall at the outer surface of said bag wall adjacent to the bag mouth.
Preferably, the bag mouth comprises a sealing means. This allows easy and safe disposal.
In one embodiment, the bag is of plastics material.
Preferably, the bag walls are opaque.
DETAILED DESCRIPTION OF THE INVENTION
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be more clearly understood from the following description of some embodiments thereof, given by way of example only with reference to the accompanying drawing in which:
FIG. 1 is a cross-sectional side view showing a disposal device of the invention in use;
FIG. 2 is an elevational view of the device from one side and FIG. 3 is an elevational view from the other side;
FIG. 4 is an elevational view of the device in a closed position;
FIG. 5 is a cross-sectional view of the device in the direction of the arrows V--V of FIG. 4.
FIG. 6 is a cross-sectional side view of the mouth area of the disposal device on a large scale; and
FIG. 7 (a) to 7 (d) are diagrams showing operation of the device.
Referring to the drawing, there is shown a disposal device 1 of the invention. The disposal device 1 comprises a bag 2 having a first wall 3 and a second wall 4. The bag 2 also comprises a mouth 5 having a press seal 6. The walls 3 and 4 are of opaque plastics material.
The device 1 also comprises a scraper 10 of rigid card material. The scraper 10 comprises a blade 11 and a handle 12 extending from the central part of the blade 11. The scraper 10 is connected to the inside surface of the first bag wall 3 by a chute 13 of plastics material. The chute 13 has approximately the same width as the scraper 10 and it is connected to the first bag wall 3 by a transverse heat seal 14.
The device 1 also comprises a scooper 15 of rigid card material. The scooper 15 comprises a blade 16 and an integral transverse handle 17. The handles 12 and 17 are best viewed in FIGS. 2 and 3. The scooper 15 is connected by a chute 18 of plastics material to the second bag wall 4 at its inner surface. The connection is by way of a transverse heat seal 19, similar to the seal 14. Again, the chute 18 is of approximately the same width as the scooper 15. The positions of the seals 14 and 19 are quite close to the mouth 5.
Finally, the device 1 comprises a tab 25 of plastics material connected to the first bag wall 3 at its outer surface close to the mouth 5. The tab 25 is connected to this wall by a heat seal. The mouth area of the device I is best illustrated in FIGS. 5 and 6.
In operation, the disposal device 1 operates in an analogous manner to a dustpan and brush, as illustrated in FIG. 1 and FIGS. 7(a) to 7(d). As shown in FIG. 7 (a), the user holds the scooper 15 by the handle 17 on one side of the device 1. The user also takes the scraper 10 with the other hand, holding it at the handle 12. The scooper 15 is moved downwardly underneath the dirt D to be disposed of. This movement of the scooper 15 underneath the dirt is assisted by the scraper 10 which holds the dirt in position as the scooper moves underneath it. The scraper 10 may additionally be required to scrape some of the dirt towards the scooper 15, depending on the nature and spread of the dirt.
The dirt D is then held on the scooper 15 and when this is lifted up, it falls into the bag 2 via the chute 18. Some of the dirt may also fall into the bag via the chute 13 of the scraper 10. As is clear from FIG. 7(b), the scraper is inserted into the bag firstly while the device is being held by the scooper 15. The user then holds the device 1 by the tab 25 while he or she places the scooper 15 into the bag, as shown in FIG. 7(c). Of course, the sequence may be reversed, with the device being held initially by the scraper 10.
Finally, as shown in FIG. 7 (d) the bag is sealed using the press seal 6.
It will be apparent that disposal of the dirt D has been achieved without the need for the user's hands to come into contact with the dirt. Also, the action for disposal of the dirt D is analogous to that of a conventional dustpan and brush, and thus the action is a very natural and simple action which may be easily performed by the user. The tasks of scooping and at the same time holding or scraping are very simple. These actions also allow for disposal of a wide range of messy dirt, such as dog excrement from the ground, or vomit from a seat fabric. It is very simple for the user to insert both the dirt and the parts of the device 1 which have come into contact with the dirt into the bag without contaminating either his/her hands or any other item, and the bag is then sealed in a very simple manner.
It will also be appreciated that the disposal device 1 has a very simple and compact construction. It takes the form of an envelope and all of the parts of the device 1 are interconnected. Because of the simple and compact construction, it is envisaged that they may be produced in packs of at least 10 items and may therefore be easily stored, for example, in a vehicle glove compartment or in the pocket of a user walking a dog. Also, because of its simplicity, the device is inexpensive to produce.
Another advantage is that the bag is closed after use, with clean outer surfaces. It may therefore be easily carried to the nearest disposal site.
The invention is not limited to the embodiments described, but may be varied in construction and detail within the scope of the claims. For example, it is not necessary that the bag be of plastics material. It may, for example, be of a biodegradable material such as cardboard or any other suitable material. If it is of a material which is not waterproof, the bag wail may be lined on one side. The tab may be on the second bag wall, or there may be a tab on both sides. The scooper may have a different shape, such as a pointed edge, Also, the chutes and the bag walls may be formed from the same sheet of material, with a fastener being attached on the outside to allow the chutes to be inserted and the bag closed. The chutes may also be connected to the bag walls at lower positions, even at the lowermost parts of the bag walls. | A disposal device is used for disposal for messy dirt such as dog excrement. The device provides a disposal action analogous to that of a dustpan and brush. A scooper is pushed underneath the dirt on the near side, while a scraper pushes the dirt towards the scooper. The dirt falls into the interior of the bag via a chute connecting the scooper to a wall of the bag. The scooper and the scraper are dropped into the bag and the bag is then sealed by a seal. | 4 |
BACKGROUND OF THE INVENTION
This invention relates generally to vapor deposition apparatus and methods for producing doped semi-conductors and particularly to the deposition of silicon dioxide films on silicon wafers. Still more particularly, this invention relates to rapid, relatively low temperature vapor deposition of silicon dioxide films on silicon wafers while eliminating unwanted deposition of the silicon dioxide film in the deposition chamber.
There is considerable interest in low-temperature techniques for depositing silicon dioxide films on silicon substrates to reduce dopant redistribution, wafer warpage, defect generation and to provide an insulator which requires no high-temperature steps for double level metallization. Deposition at low temperature also permits the use of layered photoresist-silicon dioxide-photoresist structures for high resolution lithography. Atmospheric chemical vapor deposition and low temperature low pressure chemical vapor deposition techniques, while reducing process temperatures, are deficient in uniformity, purity and film stability.
Plasma enhanced chemical vapor deposition techniques have made low temperature deposition temperature possible with improved physical characteristics, but plasma techniques are not always non-destructive, especially for radiation sensitive metal-oxide-semiconductor (MOS) devices. In plasma assisted chemical vapor deposition the substrate is bombarded with energetic neutral particles, charged particles and vacuum ultraviolet (VUV) photons, all of which contribute to chemical and physical damage to the substrate, the interface and the growing film. Another disadvantage of plasma deposited films is that the plasma potential is always more positive than the walls of the deposition chamber. Therefore, ions are accelerated by sheaths at the walls, thereby enhancing impurity sputtering and flaking, both of which degrade film quality. Plasma process parameters such as radio frequency power, radio frequency, gas flow, electrode spacing, total pressure, and substrate temperature are so interrelated that it is impossible to characterize and control defects due to a single parameter.
Because of the difficulties associated with atmospheric chemical vapor deposition, low temperature chemical vapor deposition and plasma enhanced chemical vapor deposition techniques, interest in photochemically deposited insulating films in which the reaction energy is selectively provided by photons has increased considerably. Previous workers have used both mercury photosensitized reactions and direct photolytic reactions to deposit silicon dioxide at low temperatures. Mercury lamps provide incoherent ultraviolet strong photons and vacuum ultraviolet weak photons to liberate atomic oxygen from molecular donor molecules by photodissociation. The use of mercury lamps causes the entire illuminated volume of gas to react to form products, Unwanted deposition and loss of reactants on reactor walls may be considerable and deposition rates are low. The best mercury sensitized deposition rate is just under the 200 A/min. The limitation of deposition rate is attributed to loss of atomic oxygen by recombination on surfaces of the reactor vessel.
High deposition rate is of concern in economical production processes and can ultimately determine film purity, given the background pressure of impurities and the desired film thickness. Therefore, there is a need in the art for new methods of film deposition, which improve the characteristics of inter-layer dielectrics, such as step coverage, uniformity, film integrity, speed of deposition and elimination of unwanted deposition and loss of reactants on reactor walls.
SUMMARY OF THE INVENTION
This invention overcomes the difficulties associated with previous apparatus and methods for vapor deposition of producing doped semi-conductors. The invention is particularly suitable for vapor deposition of silicon dioxide films on silicon wafers.
The present invention includes a vapor deposition chamber including means for connection to an oxygen donor and a silicon donor. A coherent light source provides an optical beam that is input to the vapor deposition chamber through a window. A boat placed in position by a conveyor or other suitable means, carries at least one and preferably a plurality of wafers into the vapor deposition chamber for alignment into the optical beam, which is preferably formed as a sheet of light that extends over an area approximately to the surface area of the boat and wafers. The wafers are mounted at their edges in alignment with openings in the boat. The openings are aligned with a suitable source of infrared radiation, such as a halogen lamp when the wafers are aligned with the optical beam from the coherent light source. The infrared radiation source heats the wafers to a temperature appropriate for vapor deposition within a few seconds after the wafers are properly positioned for vapor deposition within the deposition chamber. A window between the infrared light source and the wafers maintains the infrared light source in isolation from the wafers and donor gases supplied to the vapor deposition chamber. The infrared light source may further include a reflector, such as a parabolic mirror for forming a uniform beam of infrared radiation for incidence upon the wafers through the windows. The windows are preferably mounted on bellows that include means for adjusting the distance between the windows and the wafers.
The present invention provides significant advantages over previous apparatus and methods for vapor deposition. Heating the wafers prior to deposition with the infrared light source permits heating the wafers to the proper temperature for vapor deposition in a few seconds whereas typically prior art devices and methods require as much as six minutes to heat the wafers to the deposition temperature. It is well known that in a laser induced vapor deposition system, deposition occurs on surfaces that are at optimal temperatures to enhance the deposition. Prior art apparatus and methods for vapor deposition typically heat the walls of the vapor deposition chamber while heating the wafers so that a significant amount of deposition occurs on the walls of the chamber. The present invention rapidly heats the wafers to the deposition temperature and deposition proceeds without significant deposition upon the chamber walls. Having the infrared heat source isolated from the wafers insures that the infrared light sources experience no vapor deposition, which would drastically reduce the effectiveness of the infrared light sources as means for heating the wafers prior to vapor deposition.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic representation of the apparatus used in the vapor deposition process;
FIG. 2 is a perspective view of the vapor deposition chamber of FIG. 1;
FIG. 3 is an enlarged perspective view of a bellows including in the vapor deposition chamber for adjusting the position of a quartz window relative to a wafer;
FIG. 4 is a perspective view of a boat used to carry wafers into the vapor deposition chamber; and
FIG. 5 is a cross section of the boat of FIG. 4 showing a wafer and bellows.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 3, a vapor deposition apparatus 10 according to the invention includes a vapor deposition chamber 12, a coherent light source 14, a bellows apparatus 62, and a radiant heat source 18.
The coherent light source 14 may be any commercially available laser that produces light of a wavelength suitable for initiating vapor deposition upon a wafer 22 positioned within the vapor deposition chamber 12. One suitable laser is a Lumonics 860T Excimer Laser operated on the 193 nm ArF line to form a rectangular beam. A cylindrical lens telescope 23 focuses the rectangular beam onto a beam splitter 24 that transmits most of the light incident thereon and reflects a selected portion, which may be 2-5%, onto a photodetector 26. The output of the photodetector 26 is proportional to the power of the output beam of the coherent light source 14 and is input to a power meter 27 for monitoring the power output of the coherent light source 14.
The beam transmitted through the beam splitter 24 provides a sheet 25 of photons that are incident upon a window 28 chosen to be essentially transparent to the wavelength output by the coherent light source 14. The window 28 may be conveniently formed of an ultraviolet transmissive quartz or similar substance. The wafer, or substrate, 22 is mounted in the vapor deposition chamber 12 so that the sheet of photons is parallel to the wafer 22 and a controlled distance therefrom. The distance between the wafer 22 and the sheet of photons is preferably less than 1 mm and is typically about 0.3 mm. After propagating past the wafer 22, the optical beam exits from the vapor deposition chamber 12 through a second window 29, similar to the window 28 and is incident upon a second power meter 30. The ratio of the power output of the coherent light source 14 to power incident upon the power meter 30 is indicative of the optical power used in the deposition process.
A gas tank 31 provides an oxygen donor to the vapor deposition chamber 12 through a metering device 32 and a manifold 34 under control of a valve 36. A similar tank 38 provides gaseous silicon donor through a metering device 42 and the manifold 34 under control of a valve 44. The oxygen and silicon donors may conveniently be N 2 O and 5% silane, SiH 4 , in nitrogen. The silicon and oxygen donors mix in the manifold 34 and may be input to the vapor deposition chamber 12 at a pair of inlets 46, 48.
Referring to FIGS. 1, 2 and 3, the vapor deposition apparatus 10 includes at least one and preferably a plurality of glass plates 58A, 58B 58C 58D, that are preferably formed of a substance such as quartz, which is transmissive to infrared radiation, mounted in the vapor deposition chamber 12 on a plurality of corresponding bellows members 62A, 62B, etc. that are connected to a lower wall 60 of the vapor deposition chamber 12. Vacuum-tight seals 50 seal the junctions of the bellows 62A, 62B, etc. to the quartz plates 58A, 58B, etc. Each bellows contains a corresponding halogen lamp 66 which outputs infrared radiation. A plurality of reflectors 68 which are preferably parabolic, reflect the output of the halogen lamps 66 to provide substantially uniform radiation to the plates 58A, 58B, etc., which may, for example, be 4-6 inches in diameter. A plurality of rods 70-72 connected to the bellows 62 permit adjustment of the height and angle of the plate 58 relative to the wafer 22. The halogen lamp 66 and the reflector 68 thus provide heat to a wafer 22 positioned above the plate 58.
The coherent light source 14 produces a beam that results in the sheet of photons described above extending through the housing 12 just above the plates 58A, 58B, etc.
Referring to FIGS. 1, 2 and 4, a boat 76 having wafers 22A, 22B, etc. mounted thereon is moved by any convenient means such as a conveyor chain or belt 78 so that the wafers 22A, 22B, etc. are positioned in alignment with the halogen lamps 66A, 66B, etc. The boat 76 and conveyor 78 (not shown) position the wafers 22A, 22B, etc. in the vapor deposition chamber 12 in alignment with the corresponding quartz plates 58A, 58B, etc. The boat 76 includes at least one and preferably a plurality of generally circular openings 82A, 82B, etc. formed therein smaller in diameter than the wafers 22. Each of the circular openings 82A, 82B, etc. includes a notch 84 that forms a shoulder 86 for supporting the wafers 22A, 22B, etc. The diameter of the circle formed by the notch 84 is slightly larger than that of the wafers 22A, 22B, etc. so that they may be easily inserted into and removed from the boat 76. The boat 76 has a multiplicity of passages 77 therethrough so that the donor gases pass through the boat 76 to continuously supply the substances being deposited to the wafers.
The lower surface of the boat 76 is preferably in direct abutment with the quartz plates 58A, 58B, etc. when the wafers 22A, 22B, etc. are positioned for vapor deposition. The lower surfaces of the wafers 22A, 22B, etc. are preferably spaced about 5 mm from the quartz plates 58A, 58B, etc. to avoid scratching the quartz plates 58A, 58B, etc.
Each of the rods 70-72 may be threadedly connected to a corresponding servomotor 90. The quartz windows 58A, 58B, etc. will normally be lowered a distance sufficient to prevent scratching while the boat 76 moves into position in the deposition chamber 12. The servomotors are used to lower the quartz windows 58A, 58B while the boat is entering or leaving the deposition chamber 12 and to position the quartz windows 58A, 58B, etc. after the boat is in position for deposition. In some applications it may be desired to tilt one or more of the quartz windows 58A, 58B, etc. relative to the boat 76 to control application of heat to the wafers 22A, 22B, etc. Divergence and irregularities in the beam 25 may create "hot" or "cold" spots adjacent the boat 76. Controlling the distance and angular orientation of the quartz windows 58A, 58B, etc. and the wafers 22A, 22B, etc. provides a degree of control over the rate of vapor deposition on the individual wafers 22A, 22B, etc.
Silane, having an absorption cross section of 1.2×10 -21 cm 2 , is normally transparent to wavelengths in the 193 nm region. However, direct deposition of silicon occurs following photodiassociation of silane by ArF laser irradiation with a power threshold less than 10 megawatts per square centimeter. The focused ArF laser 14 when run at a 100 Hz repetition rate provides 10 ns pulses with a peak power of 40 MW/cm 2 . The reaction volume has a cross sectional area of about 1.5 mm×12 mm. N 2 O (Scientific Gas Products USP grade, without further purification) is used as the oxygen donor, since N 2 O is far more stable than molecular oxygen in the pressure of silane over a wide range of pressures, temperatures and flow ratios.
The quantum yield for disassociation of N 2 O is 1.0 in the 138-210 nm wavelength region and its photo chemistry is well-categorized for single-photon excitation. The photofragment kinetics of N 2 O following irradiation by an ArF laser such as the coherent light source 14 are also known. The primary product is reactive excited atomic oxygen according to the equation
N.sub.2 O+hf (193 nm) N.sub.2 +O (.sup.1 D)
The reaction kinetics in the vapor deposition apparatus 10 are controlled by competition between quenching and recombination of atomic oxygen, oxidation of silicon hydrids, creation of reactive nitric oxide species and substrate reactions. The vapor deposition apparatus 10 provides enhanced substrate reactions because radiant heat from the halogen light source 66 heats the wafers 22A, 22B, etc. to a proper temperature for vapor deposition and because of the close proximity of the excitation volume of the beam 25 to the wafers 22A, 22B, etc. At the same time, the walls of the vapor deposition chamber 12 are relatively far from the excitation volume. Since Auger analysis and infrared (IR) spectrophotometry show low nitrogen incorporation into the deposited silicon dioxide films, it is believed that only the oxygen species O 2 and O( 1 D, 3 P) are important in silicon dioxide film growth kinetics.
After the boat 76 and the wafers 22A, 22B, etc. are properly positioned, and the vapor deposition chamber 12 is sealed to be vacuum tight, the valves 36 and 44 are opened to permit the gaseous silicon and oxygen donors to flow into the vapor deposition chamber 12. The silicon and oxygen donors are mixed in the manifold 34; and a vacuum pump 90 connected to the vapor deposition chamber 12 maintains gas flow therethrough at a pressure of about 8 Torr. Suitable flow rates are 70 sccm 5% SiH 4 in N 2 and 800 sccm N 2 O. Although the vapor deposition apparatus 10 substantially eliminates unwanted depositions from forming, it may occassionally be necessary to purge the windows 28 and 29 to eliminate opaque deposits from forming thereon.
Radiant heat from the halogen lamp 58 elevates the temperatures of the wafers 22A, 22B, etc. to a proper operating level in approximately 3 seconds with only minimal heat being transfered into the vapor deposition chamber 12. Conventional conductive heating apparatus and methods often require as long as 5 to 6 minutes to properly heat wafers and result in substantial amounts of heat being transfered to the walls of the vapor deposition chamber 12 and to the surfaces of the windows 28 and 29. Since the silicon dioxide vapor tends to deposit on surfaces having temperatures higher than room temperature, rapidly heating the wafers 22A, 22B, etc., with the lamp 66 substantially eliminates unwanted vapor deposition on the vacuum deposition chamber 12 and windows 28 and 29 while substantially enhancing the vapor deposition upon the heated wafers 22A, 22B, etc.
At temperatures below 200° C., deposited silicon dioxide films were milky in appearance and easily scratched. All films formed at temperatures above 200° C. were transparent and uniform in appearance. Films produced at temperatures of 250° C. and above were extremely scratch resistent and adherent. Such films were unaffected by mechanical scribing and adhere more strongly to the wafer 22 than to pressure-sensitive adhesive tape.
In order to demonstrate the efficacy of the vapor deposition apparatus 10, Tables I and II show measured physical and electrical properties of photolytic silicon dioxide films as functions of temperature of the wafer 22 during deposition. Included for comparison are a low pressure chemical vapor deposited film (860° C.; SiCl 2 H 2 and N 2 O) and a thermal oxide (1,000° C.; trichloroethylene and O 2 ) film, both of which underwent capacitor fabrication and testing with the photolytic oxides.
Measurements of surface states (N ss ), flatband voltage (V FB ), and breakdown voltage (V B ) were obtained both from polysilicon gate MOS capacitors (2×10 -4 cm 2 area) and from evaporated Al gate capacitors (0.03 cm area). Polysilicon capacitor fabrication consists of additional high-temperature steps including a densification at 950° C. in N 2 for 60 minutes, whereas aluminum capacitors only undergo a 425° C. anneal for 30 minutes (10% H 2 90% N 2 ).
Etch rate and index of refraction measurements were made on both as-deposited and densified films. Etch rates of undensified films decrease with increasing deposition temperature. Etch rate reduction occurs upon densification, becoming comparable to thermal oxide.
Pinhole density measurements were made after a 30-min (10% H 2 , 90% N 2 , 425° C.) anneal. Pinhole densities for films deposited at ≧350° C. were less than 1 cm -2 as measured on a Ga Sonics Pinole Density Monitor.
Breakdown voltages were measured on a Tektronix Model 117 curve tracer using two techniques: (1) 20 V per second increase until breakdown and (2) 2 V/s increase with a 1.0-minute dwell every 10 V. Separate scans were made using ac and dc applied voltages.
Refractive index and thickness measurements were made with an ellipsometer. Thickness measurements were verified on a Dektak profilometer and with a Nanospec film depth computer. These measurements were taken before and after densification except for the 250° and 300° C. deposits. Variation in refractive index due to densification was 1%, and thickness reductions of 10-15% were seen in agreement with previous work. The index of refraction for the photolytic oxides closely agrees with the thermal oxide.
The N ss values for phtolytic oxides were 10 to 100 times larger than for LPCVD and thermal oxides. These differences may be due to the fact that the photolytic oxides were grown on wafers handled in an uncontrolled laboratory environment, while the LPCVD and thermal oxides were grown on wafers handled in an uncontrolled laboratory environment, while the LPCVD and thermal oxides were grown in a clean room envionment. Sputter-profiled Auger and secondary ion mass spectroscopy (SIMS) showed evidence of hydrocarbond throughout the films probably due to oil backstreaming from the fore pump in our laser photodeposition setup.
Deposition rate of SiO 2 films is independent of substrate temperature between 20° and 600° C. and directly proporational to gas pressure and laser intensity. During profile measurements of oxide thickness, low-temperature SiO 2 films (<200° C.) were damaged by the stylus as they were mechanically soft.
Since the reactant gas mixture used was 89% N 2 O 10% N 2 , and 1% SiH 4 , nitrogen incorporation in the SiO 2 films was a concern. By using IR spectrophotometry a shift of less than 20 cm -1 of the 1080 cm -1 Si-O absorption peak toward 850 cm -1 Si-N peak was measured. This corresponds to less than 5% Si 3 N 4 content in the SiO 2 films. In addition, sputtering Auger analysis was used to analyze incorporation of nitrogen in the films and showed 2-4% nitrogen content. Hence there is low nitrogen incorporation in the films, the bonding of which is unknown. Index of refraction values in Table I also show that the films are neither silicon rich nor nitride rich.
TABLE I______________________________________Properties of photodeposited SiO.sub.2 films. OxideTemp. depth(a) N.sub.ss (10.sup.11 cm.sup.-2) V (V)°C..sup.a P--Si Al P--Si Al P--Si Al______________________________________500 2009 1440 8.2 1.3 -8.0 -0.3450 1670 1460 8.6 1.5 -8.3 -0.4400 1930 1630 7.4 2.6 -8.3 -1.3350 1700 -- 10 -- -9.8 --300 1800 1300 12 4.5 -11.8 -2.1250 1940 -- 9.5 -- -10.4 --Thermal 978 -- 0.3 -- -1.3 --oxideLPCVD 1800 -- 1.9 -- 0.1 --______________________________________
TABLE II______________________________________Properties of photodeposited SiO films. as-depos. Densified Refrac- Breakdown PinholeTemp. etch rate etch rate tive voltage density°C. (A/s).sup.b (A/s).sup.b index V (MV/cm) (cm)______________________________________500 48 16 1.452 8.8 c450 57 11 1.464 9.0 c400 67 20 1.447 7.9 c350 83 14 1.457 8.9 1300 92 -- 1.473 9.4 4-6250 102 -- 1.476 5.2 16Thermal 14 -- 1.452 8oxideLPCVD 41 -- 1.440 8.2______________________________________ .sup.a Substrate temperature during photolytic oxide deposition .sup.b 5 to 1 buffered HF. .sup.c None observed.
The apparatus and method of the present invention have significant advantages over prior vapor deposition techniques. This invention requires a relatively short cycle time due to the heating of the substrates 22 in just a few seconds and due to the high deposition rate of 1,000 A per minute. The substrates 22 need to be at the deposition temperature of 300-450 degrees Celsius for only about 5-10 minutes, depending on the required thickness of the material to be deposited. LPCVD AND PECVD techniques require that the substrates sit at temperatures for approximately 120 minutes.
Since the invention provides vapor deposition at relatively low temperatures, the walls of the vapor deposition chamber are cold. Reactants are generated only in the path of the laser beam 25, which is spaced apart from the chamber walls. Therefore, only minimal deposition occurs on the surfaces of the vapor deposition chamber.
Unlike the PECVD technique, which produces photons at energies greater than 10 eV in all directions, the coherent light source used in the invention produces photons of energies less than 6.4 eV directed so as to not impinge upon the surfaces of the substrates 22. No high energy photons are incident upon the substrates 22. Therefore, in the vapor deposition process of the invention the substrates 22 experience substantially no radiation damage.
The laser enhanced vapor deposition technique of the present invention is simplier than the LPCVD or PECVD techniques. Deposition rate is independent of the temperature of the substrate and is linear with respect to the photon flux in the coherent light beam 25.
Because of the relatively low temperature of the vapor deposition chamber, the system lends itself to automated substrate handling schemes.
The apparatus and method of the present invention may be used for depositing many different types of materials, such as silicon nitride, molybdemum, turgsten, tantalum, chromium, and aluminum.
Since the laser beam 25 does not impinge upon the surfaces of the substrates 22 and since vapor deposition can be done at 200 degrees Celcius, LECVD can be used to deposit films on temperature-sensitive structures such as organic photoresists. | This invention relates to apparatus and methods for laser induced vapor deposition upon a substrate. The invention includes apparatus isolated from the deposition chamber for preheating the substrate before deposition. A bellows arrangement permits adjustment of the heat applied to the substrate. | 7 |
FIELD OF THE INVENTION
[0001] This invention relates to a method and associated system for seafloor mining. In particular, the invention relates to a method and associated system for deepwater seafloor mining in areas which are exposed to non-benign seastates and/or cyclonic (or similar) weather events. However, it should be appreciated that the method and system for seafloor mining may be used in sheltered waters or benign seastate locations.
BACKGROUND OF THE INVENTION
[0002] The deep sea contains many different resources available for extraction, including silver, gold, copper, manganese, cobalt, and zinc. These raw materials are found in various forms on the sea floor, usually in higher concentrations than terrestrial mines. However, most of these deposits are found in water having a, depth of between 1,000 and 6,000 meters. Therefore there are substantial technical challenges mining and transporting ore from the seafloor.
[0003] In order to mine the ore from the deposits, the applicant has developed a method and system for seafloor mining. The system includes a dynamically suspended subsea pump located at the bottom of a vertical riser that extends to a surface vessel. A combination of seafloor production tools excavate and deliver the mineralised ore in slurry form to the pump via a horizontal transport pipe. In use, the ore travels through the horizontal transport pipe, up through the riser and into the surface vessel. The ore is then dewatered and transferred to a barge.
[0004] The above method and system for seafloor mining is primarily for use in relatively calm ocean water. That is, the above method and system for seafloor mining is impractical or unfeasible in areas that are disposed to large wave height fluctuations especially evident in cyclone (or typhoon) prone, locations. This is largely due to riser sensitivity and to high riser dynamic loading and the seastate limitations associated with the transfer of ore from the mining support vessel to an adjacent barge.
[0005] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge in Australia.
OBJECT OF THE INVENTION
[0006] It is an object of the invention to overcome or alleviate one or more of the disclosures or provide the consumer with the useful or commercial choice.
SUMMARY OF THE INVENTION
[0007] In one form, although not necessarily the only or broadest form, the invention relates to a system for seafloor mining comprising:
[0008] a vertical riser anchored to the seafloor;
[0009] a mining machine to deliver seafloor ore to the vertical riser;
[0010] a lifting system to pass the ore through the vertical riser; and
[0011] a transport vessel removably connected to the vertical riser to receive ore from the vertical riser.
[0012] The vertical riser is preferable in the form of a rigid riser. However, it is possible that the vertical riser is a flexible riser. It is also envisaged that the vertical riser may be formed from a rigid section and a flexible section.
[0013] At least one buoyancy device may be used to support the vertical riser. The buoyancy device may be in the form of a buoyancy tank. The buoyancy of the buoyancy tank may be varied.
[0014] The lifting system may be of any suitable form. The lifting system may be in the form of a subsea pump. The subsea pump is normally located adjacent a bottom of the vertical riser.
[0015] An alternative lifting system may use air to lift the ore through the vertical riser. The air may be pumped into the vertical riser. Sufficient air may be pumped into the vertical riser at a position to lift the ore. This position may be varied according to design. An air supply line may extend down the vertical riser to deliver air into the vertical riser. A compressor may be attached to the air supply line to enable air to travel through the air supply line.
[0016] The transport vessel may include a cargo hold for storage of the ore. The transport vessel may include a processing plant for de-aerating and/or dewatering the ore.
[0017] A jumper may be used to connect the mining machine to the vertical riser. The jumper may be connected to adjacent the bottom of the riser. A quick coupling may be used to connect the jumper to the mining machine.
[0018] A flexible link hose may be used to connect the vertical riser to the transport vessel. A quick coupling may be used to connect the jumper to the mining machine.
[0019] A support vessel may be used to control the operation of the mining machine. The support vessel may be linked to the mining machine via an umbilical.
[0020] The mining machine may be used to excavate ore to supply to the vertical riser. Alternatively, the mining machine may be used to retrieve already excavated ore and supply them to the vertical riser. It should be appreciated that more than one mining machine may be connected to the vertical riser.
[0021] In another form, the invention resides in a method for seafloor mining including the steps of:
[0022] connecting a mining machine from a vertical riser which is anchored to the seafloor; and
[0023] connecting a transport vessel from the vertical riser.
[0024] The method may further include one or more of the steps of:
[0025] commencing operation of a lifting system;
[0026] lowering a mining machine from the seafloor.
[0027] disconnecting a mining machine from a vertical riser which is anchored to the seafloor;
[0028] disconnecting a transport vessel from the vertical riser;
[0029] discontinuing operation of a lifting system; and
[0030] retrieving a mining machine from the seafloor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] Embodiments of the invention, by way of example only, will now be described with reference to the accompanying figures in which:
[0032] FIG. 1 is a schematic view of an operational system for seafloor mining according to a first embodiment of the invention;
[0033] FIG. 2 is a schematic view of a non-operational system for seafloor mining; and
[0034] FIG. 3 is a schematic view of a system for seafloor mining according to a second embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] FIG. 1 shows a system for seafloor mining 10 for use in areas which have large wave height fluctuations and/or are located in cyclone prone areas. However, it should be appreciated that the system 10 for seafloor mining may be used in low wave height areas. The system 10 includes a vertical riser 20 , a subsea pump 30 , a mining machine 40 , a transport vessel 50 and a support vessel 60 .
[0036] The vertical riser 20 is used to transport ore received from the mining machine 40 to the transport vessel 50 . The vertical riser 20 is constructed from a rigid pipe which is anchored to the seafloor via an anchor 21 . The anchor 21 can be in the form of a clump weight, piled foundation structure or an alternate vertically loaded foundation apparatus. A chain 26 or other suitable tether is normally used to attach the vertical riser 20 to the anchor 21 . The type and size of the vertical riser 20 and would readily be chosen by a person skilled in the art depending on design requirements.
[0037] A dump valve 24 is located adjacent a bottom of the vertical riser 20 . The dump valve 24 is used to ensure the vertical riser 20 does not become blocked during an uncontrolled shut down. In an uncontrolled shut down, the dump valve 24 is opened thereby releasing ore from vertical riser 20 through an outlet 25 located below the dump valve 24 . It would be appreciated by a person skilled in the art that there are numerous ways in which the dump valve 24 is activated at an appropriate time.
[0038] A buoyancy tank 23 is attached to adjacent the top of the vertical riser 20 . The buoyancy tank 23 is used to assist in maintaining the tension in the vertical riser 20 . The positioning of the buoyancy device 23 is at a depth where the waves do not cause unacceptable loading or movement on the riser 20 . Accordingly, the size and form of the buoyancy tank 23 would be evident to a person skilled in the art. The vertical riser 20 passes through buoyancy tank 23 .
[0039] The buoyancy of the buoyancy tank 23 can be varied to allow relocation of the vertical riser 20 . The buoyancy of the buoyancy tank 23 can be varied by varying the amount of water that is located within the buoyancy tank 23 . Once mining at a site is completed, the buoyancy tank 23 is partially flooded to reduce the tension of the chain 26 between the vertical riser 20 and anchor 21 . For such an operation, the riser 20 can be supported from surface by the transport vessel 50 or the support vessel 60 whilst the chain 26 at the base of the vertical riser 26 is disconnected from the anchor 21 . Once the chain 26 has been removed, the vertical riser 20 can be relocated and connected to another anchor 21 at the next location. Air can then be added to the buoyancy tank to remove the water and allow the buoyancy tank to support the vertical riser 20 .
[0040] The subsea pump 30 is used to pump the ore from the seafloor to the transport vessel 50 . The subsea pump 30 is located adjacent the end of the vertical riser 20 . The size and type of the subsea pump 30 will be dependant on design requirements which would be readily be assessed by a person skilled in the art. It should be appreciated that the means that is used to operate the pump could be varied. For example, the pump may be powered electrically or hydraulically,
[0041] The mining machine 40 is used to mine the ore from the seafloor. The typical size of the seafloor which contains the ore is approximately 500 meters wide by 1000 meters long by about 10 to 40 meters deep. The seafloor terrain is generally very rugged. The water depth also ranges from 1,000 meters to 2,500 meters. The mining machine 40 may work on the rugged terrain with slopes as high as 25 degrees. Therefore, the mining machine 40 ideally would be designed to perform under these rugged deep sea conditions. The mining machine 40 could be designed to mine the ore by performing any combination of the following steps, including, but not limited to, (1) excavating the ore from the fields located on the seabed floor, (2) breaking down the ore into chunk sizes using a cutter mounted on the mining machine 40 , and (3) forcing the ore into a crusher located on the mining machine to crush the ore into manageable sizes to ensure the ore passes through the vertical riser 20 . It should be appreciated that the mining machine 40 may be used to simply collect ore that has been previously stockpiled so that the ore can be transferred to the transport vessel 50 . Many variations and embodiments are envisioned for the mining machine 40 .
[0042] It should be appreciated the system for mining may use a number of mining machines. These mining machines may have varying operations such as excavating ore, stockpiling ore and/or collecting ore from the stockpile. Further, there may be a number of different mining machines performing the same operation.
[0043] A jumper 70 is used to connect the mining machine 40 to the vertical riser 70 via the subsea pump 30 . The jumper 70 may also be referred to as the horizontal transport pipe or a riser transfer pipe. The jumper 70 may be configured in an arced shape. This may reduce the force exerted by the subsea pump 30 on the mining machine 40 . The other function of the arc shaped jumper 70 is to provide flexibility and range of movement of mining machine 40 relative to the vertical riser 20 .
[0044] A large radius of the jumper 70 may lower the centrifugal force and wear. Jumper buoyancy devices 71 , such as buoys are used to maintain the jumper in its arced state. A quick release coupling 72 may be located on one or more ends of the jumper to enable quick release of the jumper from the subsea pump 30 and/or mining machine 40 . A remotely operated vehicle (ROV) (not shown) may be associated with the jumper 70 to enable the quick release (or connection) of the jumper 70 with the pump and/or mining machine 40 .
[0045] The transport vessel 50 is used to store and transport ore that are removed from the seafloor. Accordingly, the transport vessel 50 includes a cargo hold 51 for placement of the ore. The transport vessel 50 also includes a processing plant 52 to both dewater and dewater the ore prior to their placement in the cargo hold 51 . The wastewater from the processing plant 52 is pumped into the sea via a dewatering pipe 54 at a depth that does not have an unacceptable environmental impact. Alternatively, the wastewater is pumped into water injection lines (not shown) which may be piggy backed onto the vertical riser 20 to power a compression chamber of the pump 30 to lift the ore to the surface vessel.
[0046] The transport vessel 50 is attached to the vertical riser 20 via a flexible link hose 80 . A quick release coupling 81 is located at the end of the hose to join the flexible link hose 80 to the transport vessel 50 . A swivel 83 is located on the transport vessel 50 , adjacent to the quick coupling 81 , in order to allow rotation or “weathervaning” of the transport vessel 50 . Hose buoys 82 are connected around the link hose 80 to enable surface retrieval of the flexible link hose 80 . It should be appreciated that the buoy 82 may be used with other types of floating devices to enable retrieval of the flexible link hose 80 such as a floating rope.
[0047] The support vessel 60 is used to transport and support the mining machine 40 . An umbilical 61 extends from the support vessel 60 to the mining machine 40 in order to control the operation of the mining machine 40 from the support vessel 60 . The support vessel 60 includes deployment and retrieval equipment 61 to both place and retrieve the transport vessel 50 as is required.
[0048] The system 10 commences operation by running the subsea pump 30 . Operation of the pump enables the mining machine 40 to excavate ore from the seafloor. It should be appreciated that movement of the mining machine 40 is controlled by an operator located within the support vessel 60 . Once the ore passes through the mining machine 40 , the ore then pass through the jumper 70 , through the subsea pump 30 and into the vertical riser 20 . The ore then pass through the flexible link hose 80 and into the onboard processing plant 81 located on the transport vessel 50 . Once the water is removed from the ore, the ore is placed within the cargo hold 51 .
[0049] In the event that the system for seafloor mining 10 is unable to continue operation due to wave height implications or simply the transport vessel 50 is full, then the flexible link hose 80 is de-coupled from the transport vessel 50 allow the transport vessel 50 to leave the location of the mine. The jumper 70 is also de-coupled from the mining machine 40 via the ROV. The placement and retrieval equipment 61 located on the support vessel 60 is utilised to remove the mining machine 40 from the seafloor. Once the mining machine 40 is removed from the seafloor, the support vessel 60 is able to travel to a safe location.
[0050] During any large wave activity, the buoyancy device 23 and vertical riser 20 are positioned below any wave activity. Therefore, the vertical riser 20 , buoyancy device 23 , subsea pump 30 and jumper 70 can remain at the mining site during a storm as shown in FIG. 2 .
[0051] In order to commence mining operations after an unacceptable storm event or seastate condition or simply to continue mining operations, both the support vessel and transport vessel 50 return to the site of the subsea mine. The transport vessel 50 retrieves the flexible link hose 80 and couples the flexible link hose 80 using the transport vessel 60 and the quick coupling 81 . The support vessel deploys the mining machine 40 to the seafloor. The ROV is used to connect the jumper 70 to the mining machine 40 . The mining operation can then commence.
[0052] It should also be appreciated that the advantages provided by the system 10 when wave heights implications become an issue also provide advantages in normal use. The quick disconnection of the transport vehicle 50 allows the transport vessel 50 to transport and/or discharge the ore in a reduced timeframe. That is, once its cargo hold is full, the transport vessel 50 disconnects from the flexible link hose 80 and transports the ore to an onshore stockpile or transfers the ore to a separate transportation vessel in sheltered waters. A further transport vessel 50 is then able to connect to vertical riser 20 via the link hose 80 to allow the continuation of mining operations.
[0053] The system 10 for mining the seafloor enables the quick removal of the mining machine 40 , the transport vessel 50 and support vessel 60 when required. Further, the system 10 allows for increased production seastate limits and hence increased production time. Still further, the support provided for the vertical riser 20 reduces dynamic and fatigue loading. Lastly, the systems provides for no offshore transfer of ore between vessels.
[0054] FIG. 3 shows an alternative embodiment of the system 10 for seafloor mining. In this embodiment the pump 30 has been replaced with an air lift system 90 . The air lift system 90 includes a compressor 91 which is mounted on the transport vessel 50 . An air supply line 92 extends from the compressor 91 , along the flexible link hose 80 and passes toward a bottom of the vertical riser 20 . The air supply hose 92 extends through the vertical riser 20 via a nipple 93 to supply air within the vertical riser 20 in order to lift ore from seafloor. It should be appreciated that the placement of the supply line 92 within the vertical riser 20 and the size of the compressor 91 is dependant on design and would be able to be determined by a person skilled in the art.
[0055] In this specification, the terms “comprise”, “comprises”, “comprising” or similar terms are intended to mean a non-exclusive inclusion, such that a system, method or apparatus that comprises a list of elements does not include those elements solely, but may well include other elements not listed.
[0056] It will also be appreciated that various other changes and modifications may be made to the invention described without departing from the spirit and scope of the invention. | A system for seafloor mining comprising a vertical riser anchored to the seafloor; a mining machine to deliver seafloor ore to the vertical riser; a lifting system to pass the ore through the vertical riser; and a transport vessel removably connected to the vertical riser to receive ore from the vertical riser. | 4 |
This application is a divisional application of parent application Ser. No. 505,789, filed on June 20, 1983, now U.S. Pat. No. 4,520,959.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed generally to automatic temperature responsive vents for use in permitting the passage of air from one defined space to another such as between an attic space through the ceiling of the room. More specifically, the present invention is directed to such an automatic vent which is temperature responsive so that its opening is automatic and which can be adjusted as to the minimum opening provided.
2. Description of the Prior Art and/or Contemporary Art
It is frequently desirable to permit the venting of air from a room space into an attic which is in itself vented to the outside atmosphere. As a result of such an arrangement, when the attic is vented through active or passive means, the rooms which employ such automatic vents can also be similarly vented. For example, cool air can be permitted to enter the rooms and simultaneously, warmer air with contaminants, odoriferous aromas and moisture can be caused to rise to the ceilings of the room and through automatic vents mounted on the ceilings into the attic space so that they can be vented from the attic space out of the building. Ventilators which are employed to vent from attic areas or the like through roofs to the atmosphere are known in the art. Such devices include those shown in U.S. Pat. Nos. 4,123,001 and 4,210,277 invented by the inventor of the subject invention. Additionally, such a roof ventilator is shown in U.S. patent application Ser. No. 500,074 also by the same inventor as the present invention.
Other ventilators are also shown in U.S. Pat. Nos. 1,737,054; 3,921,900; and 3,976,245.
Unfortunately, for various reasons, including their large size and complexity, none of the presently known automatic vents are entirely suitable for mounting on the ceilings of rooms to vent into an attic. Furthermore, these vents are primarily designed to be installed from the area where the venting is to take place to rather than from where the venting is to take place from. These vents would therefore have to be installed from an attic area, which is rather inconvenient, as compared to installation from within the room which is to be vented.
A simplified and compact construction is also desirable since this almost necessarily dictates a reduction in cost, a necessity since in order to be employed most effectively, room to attic type ventilators must be installed in every room of a dwelling which has a ceiling bounded by attic space. Another disadvantage of prior art automatic ventilators is that they can not be easily and compactly packed for transportation and delivery, therefore still further increasing the cost associated with procurement.
An additional disadvantage of prior art devices is that they are in an entirely closed position when the temperature responsive mechanisms thereof reach a set temperature or temperature therebelow. Depending on circumstances, there are instances when an entire blockage of the flow of air is not desirable and it is instead desirable to permit minimal air flow regardless of the temperature of the air adjacent to the vent. Means for accomplishing this are not shown or suggested in automatic vents known in the prior art.
The present invention overcomes the shortcomings associated with the prior art by providing an automatic temperature responsive vent for permitting the passage of air from one defined space to another which includes adjustment means that permits the desired flow of air even when the vent is essentially in a "closed" position in respect to the operation of the temperature responsive means thereof. In addition, the present invention comprises an automatic temperature responsive vent which is extremely compact in installation and which can be installed in a ceiling opening from the room side of such opening with minimal effort and expense. Furthermore, the present invention provides an automatic vent which is configured for compact shipping to further cut costs associated with installation.
OBJECTS OF THE INVENTION
An object of the present invention is to provide an automatic damper assembly for use in ventilating systems wherein rooms are to be vented into attics or other similarly defined spaces are to be vented into adjacent spaces.
Another object of the present invention is to provide an automatic damper which requires no attention and which achieves its venting function without human intervention.
A further object of the present invention is to provide an automatic temperature responsive vent which is activated automatically in response to a preselected change in temperature.
A further object of the present invention is to provide an automatic temperature responsive vent which can be adjusted so that a minimal air flow can be accomplished even when the vent is in a substantially closed position in respect to the temperature responsive means thereof.
Still another further object of the present invention is to provide an automatic temperature responsive vent which employs essentially no moving parts except for the damper flap thereof, thereby minimizing the cost of manufacture.
An additional object of the present invention is to provide an automatic temperature responsive vent which is configured such that a pair of such vents can be nestled together to permit compact shipping.
A still additional object of the present invention is to provide an automatic temperature responsive vent which can be used in conjunction with attic-type ventilators to provide an integrated house ventilation system.
Still another additional object of the present invention is to provide an automatic temperature responsive vent which is simple in design, inexpensive to manufacture, rugged in construction and efficient in operation.
Other objects and advantages of the present invention will become apparent as the disclosure proceeds.
SUMMARY OF THE INVENTION
An automatic temperature responsive vent for permitting the passage of air from one defined space to another is provided for installations such as in the ceiling of rooms of a house wherein the rooms are vented into an attic area which is itself vented to the outside atmosphere. The damper or flap of the vent is opened by a temperature responsive drive assembly which, in response to a preselected temperature, causes such opening. In addition, adjustment means are provided which are coupled to the flap of the invention, to preclude the flap from assuming an entirely closed position so that ventilation can take place to a preselected degree even when the temperature responsive assembly of the automatic vent is not activated to cause opening of the flap.
The above functions are structurally provided by a frame means which is configured for mounting adjacent to an opening from one defined space to another defined space, such a hole cut in a ceiling, the frame means having a central passage disposed therethrough. Flap means is movably mounted to the frame, preferably by suitable pivot arrangement, such that the flap means is movable from a closed position substantially blocking the passage in the frame to an open position permitting the free flow of air therethrough, the flap means assuming the closed position when at rest due to the effect of gravity. A temperature responsive drive assembly means is mounted to detect temperature changes adjacent to the opening and when activated, the drive assembly means moves the flap means from the rest position to an open position in proportion to the temperature change sensed by the temperature responsive means. Adjustment means in the form of a movable wedge which acts upon the flap means, in between the flap means and the frame means, is provided to preclude the flap from assuming a closed position when at rest, thereby providing some degree of ventilation.
To accomplish a compact configuration which is inexpensive to manufacture, the temperature responsive drive assembly means of the vent is mounted between a portion of the frame means and a portion of the flap means, the temperature responsive drive assembly means being actuated in response to temperature changes within a predetermined range. Upon actuation the temperature responsive drive assembly means expands and this expansion results in displacement of the flap means relative of the frame means. More specifically, the flap means provides a depression in which the temperature responsive means is mounted and the frame includes a protrusion which is extensible through an aperture disposed in the depression. When the temperature responsive drive assembly means expands, it exerts a force on the protrusion and causes shifting of the flap means relative to the frame.
The temperature responsive drive assembly means preferably includes a temperature-sensitive bellows power unit which essentially is an expansible metal casing that includes a gas disposed therein which expands when it reaches a selected temperature.
BRIEF DESCRIPTION OF THE DRAWINGS
Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout the several views and in which:
FIG. 1 is a partially broken-away side elevation of a house in which a plurality of automatic vents constructed in accordance with the principle of the present invention are installed;
FIG. 2 is a partially-exploded top view in perspective of an automatic temperature responsive vent incorporating the principles of the present invention therein;
FIG. 3 is a top plan view of the vent of FIG. 2;
FIG. 4 is a bottom plan view of the vent of the present invention;
FIG. 5 is a cross-sectional view taken substantially along the lines 5--5 of FIG. 2;
FIG. 6 is a cross-sectional view of the temperature responsive means of the present invention in a closed position;
FIG. 7 is a cross-sectional view of the temperature responsive means of the present invention in an open position;
FIG. 8 is a pictorial representation of a pair of vents incorporating the principles of the present invention prior to nestling and showing the nestling feature thereof; and
FIG. 9 is a side view of the vents of FIG. 8 in a nestled position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the Figures and more particularly, to FIG. 1 thereof, there is illustrated therein a house H having an attic A and a room R adjacent to the attic A. An automatic roof ventilator V is installed in the roof of the house H and vents the attic A to the outside atmosphere. A pair of energy saving automatic temperature responsive vents 10 are installed in the ceiling C of the house H above the room R and serve to vent the room R into the attic A. The construction of the vents 10 will be hereinafter described in conjunction with FIGS. 2 through 9. The vents 10 are each constructed so that they open upon the air adjacent thereto reaching a certain selected temperature and, as is illustrated by the arrows in FIG. 1, can be employed to permit fresh air to enter the room R and stale air to be exhausted into the attic A where it is then vented to the outside atmosphere through the vent V. Depending on the adjustment of the automatic temperature responsive vents 10, they can be entirely closed when a preselected temperature is not reached or can be opened a desired degree to permit ventilation even if the preselected temperature has not been reached. In a typical installation, one automatic temperature responsive vent 10 would be placed in the ceiling of each room adjacent to an attic so that each room would have an equal opportunity to have the contaminated and/or undesirable air vent therefrom through the attic to the outside atmosphere.
With reference to FIGS. 2 through 4, the vent 10 is seen to include a frame 12 and a flap 14. The flap 14 is pivotally affixed to the frame 12 by a pair of pivot rods 16 that are integrally formed with the flap 14 and which journal in apertures disposed in the frame 17 in a conventional manner. The frame 12 has a central passage 18 disposed therethrough which is selectively blocked by the flap 14 depending upon its position relative to the frame 12 as it pivots on the pivot rods 16. The frame 12 has the central passage 18 thereof covered by a grille 20 to form an exposed appearance, as shown in FIG. 4, which is similar to that of conventional vents or registers. Of course, although the grille 20 is shown in a particular pattern and configuration, it is to be understood that those of ordinary skill in the pattern and art could modify this configuration as desired.
In order to minimize costs of manufacture, the frame 12 and flap 14 are preferably constructed of plastic, a material well-suited for such an application. The pivot rods the flap 14 or instead, can take the form of integrally-formed protrusions which are molded with the flap 14 as noted above or can be formed by a rod which extends through the flap 14. The edges of the flap 14 include a plurality of mounting apertures 22 for securing the frame 12 to a supporting surface such as ceiling C of FIG. 1. When mounted, the grille 20, as shown best in FIG. 4, forms the portion of the automatic responsive vent 10 which is exposed, the unexposed surfaces of the vent 10 being shown in FIG. 3. The flap 14 has a central depression 24 disposed therein for accommodating a temperature responsive device which will be hereinafter described. Located in the central depression 24 is an aperture 26 which extends through the flap 14. The aperture 26 is dimensioned to accommodate therethrough a protrusion 28 which is formed or alternately mounted on the frame 12 via the grill 20 thereof.
With specific reference to FIG. 5, the manner in which the protrusion 28 extends through the aperture 26 can be viewed with the flap 14 being illustrated in an open position and also being shown in phantom in a closed position wherein the protrusion 28 extends through the aperture 26. With further reference to FIG. 5, that the flap 14 is molded with a substantially V-shaped ridge 30 which extends the length of the flap as can be further seen by the back indentation of the ridge 30 in FIG. 3. The ridge 30 is provided for interaction with an adjustment slide 32. The adjustment slide 32 comprises an inner button 34 and an outer button 36 joined by a shaft 38. The shaft 38 is freely slidably in a slot 40 disposed in the grille 20 of the frame 12 as shown in FIG. 5. The surface of the grille 20, adjacent to the button 34 about the aperture 40, is roughened so as to induce friction between the button 34 and the grill 20 to preclude sliding of the button without user intervention. The substantially V-shaped ridge 30 acts as an incline against which the button 34 interacts and, depending upon the placement of the shaft 38 within the slot 40, the degree that the flap is permitted to close can be varied. As illustrated in FIG. 5, when the adjustment slide 32 is at the right hand right side of the slot 40, the flap 20 is kept in an open position. As the adjustment slide 32 is moved in the slot 40 toward the right side of the drawing, the amount the flap is kept open decreases until the incline of the substantially V-shaped ridge 30 is no longer contacted and the flap 14 can entirely close the central passage 18 of the frame 12.
The interaction of the adjustment slide 32 and the substantially V-shaped ridge 30 provides an inexpensive yet effective means of adjusting the degree to which the flap 14 will close. Of course, other suitable means for adjusting the degree of closure of the flap 14 can be employed within the spirit and scope of the invention. Depending upon the particular plastic used to mold the flap 14, flexure thereof may occur where the substantially V-shaped ridge 30 is forced, by gravity, against the adjustment slide 32. To preclude this, a brace 42 as illustrated in FIGS. 2, 3 and 5 is provided. The brace 42 includes a pair of arms 44 which extend over the edge of the flap 14 to preclude flexing. The brace 42 also includes a pair of legs 44 which slide into mating receptacles 46 formed in the frame 12. When the legs 44 of the brace 42 are inserted in the receptacles 46, they are secured in position by a suitable cement or the like. A second brace 42 is supplied with the vent 10 and may be inserted and frictionally secured in a second pair of receptacles 46. The second brace 42 is supplied as a shipping expedient and acts as a temporary means for securing the flap 14 in position. When the automatic temperature responsive vent 10 arrives at its point of use, the second brace 42, illustrated in a removed position in FIG. 2, is removed and discarded.
The flap 14 is moved from its rest position, caused by gravity, as illustrated in FIG. 5 to an open position through the action of a differential force between the flap 14 and the protrusion 28 of the frame 12.
This differential force is generated by a heat responsive sealed bellows power drive unit shown in FIGS. 6 and 7 in position in the depression 24 of the flap 14. The heat responsive sealed bellows power drive unit 48 serves as a thermal power source which causes the opening of the flap 14 upon the expansion thereof. The power drive unit 48 is of a conventional design and is filled with a heat expansible fluid, the volatility of which is matched along with the shell thickness, the type of metal, and volume of the unit to provide a suitable expansion at the desired temperature range. In addition to being actuated at the appropriate design selected temperature range (80° F. to 160° F.), the power drive unit 48 of the present invention is also capable of generating a force of sufficient magnitude per square inch in order to be operable to move the flap 14 relative to the frame 12. It will be understood that any number of temperature sensitive power drive units may be utilized to perform this function so long as their expansion and contraction characteristics are predictable and the force generated is suitable over the desired temperature range.
The heat responsive sealed bellows power drive unit 48 is secured in position within the central depression 24 of the flap 14 by a strap 50 fixedly secured on the ends thereof to the flap 14. The strap 50 confines the power drive unit 48 within the central depression 24 as illustrated in FIG. 6. When the flap 14 is in a substantially closed position as illustrated in FIG. 6, the heat responsive sealed bellows power drive unit 48 assumes its minimum height. Upon being subjected to a temperature within its activation range, the power drive unit 48 expands, as illustrated in FIG. 7, exerting a force on the protrusion 28 of the grille 20 of the frame 12, thus causing opening of the flap 14 as illustrated in FIG. 7. When the power drive unit 48 is again subjected to a temperature outside its activation range, the power drive unit decreases in height and the flap 14 is closed a proportional distance. Through use of the depression 24 and the protrusion 28 cooperating with the aperture 26, the force of the power drive unit 48 is effectively exploited without necessity for any type of mechanical coupling or linkage between the power drive unit 48 and the flap 14.
Although the power drive unit 48 is shown to be fixedly secure to the flap 14 and the protrusion is provided by the grille 20, it is to be understood that the power drive unit 48 could alternately be fixedly secured to the frame 12 and especially the grille 20 thereof and the protrusion could be provided on the flap 14 to achieve the same result within the principles and scope of the subject invention. Similarly, it is to be understood that means other than the strap 50 could be employed to fix the power drive unit 48 in place. As another alternative, the heat responsive sealed bellows power drive unit 48 could be replaced with a bi-metallic thermostat in lieu of the gaseous thermostat disclosed, this variation also being within the scope of the invention.
In order to facilitate shipping so that the substantially planar surfaces of the grilles 20 can be placed adjacently on two automatic temperature responsive vents 10 an aperture 52 is disposed in the face of each such vent 10 as illustrated in FIGS. 4 and 8. The apertures 52 are sized to accommodate the buttons 36 of an adjacent vent 10 when they are placed in a close overlying relationship as illustrated in FIG. 9. This permits shipment of pairs of automatic temperature responsive vents in the minimum possible space and at the same time protects the buttons 36 of the adjustment slides 32 from being broken off the shafts 38 thereof. This same technique of providing an aperture 52 in a vent can be applied to other types of vents which incorporate different features than those shown in the present invention and it is to be understood that this aspect of the invention is equally applicable to other configurations of vents within the scope of the invention.
Although the automatic temperature responsive vent 10 has been discussed as being formed from plastic, it is to be understood that it could be made from other materials including metal or the like. In addition, configurations other than the rectangular configuration illustrated can be manufactured and square, oval, or round vents are also possible.
Although illustrative embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to these precise embodiments, and that various changes and modifications may be effected therein without departing from the principles, scope or spirit of the invention.
It is obvious to those knowledgeable in the art, that the present design of the damper assembly, when installed in the ceiling of a room which vents into an attic (or space) that vents to the outside atmosphere is capable of responding to a sudden decrease in outside pressure by completely opening and equalizing the pressures therebetween. | An energy saver automatic temperature responsive vent, for permitting the passage of air from one defined space to another, which includes a frame for mounting over an opening extending from one defined space to another defined space, the frame having a central passage disposed therethrough and a flap movably mounted to the frame, so as to be means, movable from a closed portion substantially blocking the passage to an open portion permitting the flow air therethrough, a temperature drive assembly being provided to open and close the flap in response to changes in temperature. Adjustment means are provided to preclude the flap from closing entirely, if desired. In addition, the vent is configured so that it has a recess disposed therein for accommodating the knob or the like of an adjustment means on a similar vent so that the vents can be nestled together in the most compact space possible as an expedient to shipping. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention relates to a signal processing circuit for enhancing a stereo image that corresponds to a stereo audio signal.
2. Description of the Related Art
In conventional stereo systems, the amplifying circuits amplify the left and right channel signals and pass these amplified signals to a left and right channel loudspeakers. This is done in an attempt to simulate the experience of a live performance in which the reproduced sounds emanate from different locations. Since the advent of stereo systems, there has been continual development of systems which more closely simulate this experience of a live performance. For example, in the early to mid 1970's, four-channel stereo systems were developed which included two front left and right channel loudspeakers and two rear left and right channel speakers. These systems attempted to recapture the information contained in signals reflected from the back of a room in which a live performance was being held. More recently, surround sound systems are currently on the market which, in effect, seek to accomplish the same effect.
A drawback of these systems is that there are four or more channels of signals being generated and a person must first purchase the additional loudspeakers and then solve the problem of locating the multiple loudspeakers for the system.
As an alternative to such a system, U.S. Pat. No. 4,748,669 to Klayman discloses a stereo enhancement system which simulates this wide dispersal of sound while only using the two stereo loudspeakers. This system, commonly known as the Sound Retrieval System, uses dynamic equalizers, which boost the signal level of quieter components relative to louder components, a spectrum analyzer and a feedback and reverberation control circuit to achieve the desired effect. However, as should be apparent, this system is relatively complex and costly to implement.
SUMMARY OF THE INVENTION
It is an object of the subject invention to provide a signal processing circuit for enhancing a stereo image that corresponds to a stereo audio signal that is relatively simple and inexpensive.
This object is achieved in a circuit arrangement for improving the stereo image separation in a stereo signal comprising a first and a second input for receiving, respectively, a left and a right channel signal of an input stereo signal; a summing and equalizing circuit having a first and a second input coupled, respectively, to said first and second inputs of said circuit arrangement, for receiving said left and right channel signals, means for summing the left and right channel signals thereby forming a sum signal, equalizing means for performing a high frequency equalization on said sum signal, and a first and a second output both for supplying the equalized sum signal; a difference and equalizing circuit having a first and a second input coupled, respectively, to said first and second inputs, for receiving said left and right channel signals, means for subtracting the right channel signal from the left channel signal thereby forming a first difference signal, means for subtracting the left channel signal from the right channel signal thereby forming a second difference signal, means for performing an equalization on said first and second difference signals, said equalization having characteristics of an ear of a human being, and first and second outputs for providing, respectively, the equalized first difference signal and the equalized second difference signal; first means for combining the first output of said summing and equalizing circuit with the first output of said difference and equalizing circuit, an output of said first combining means carrying a modified left channel signal and being coupled to a first output of said circuit arrangement; and second means for combining the second output of said summing and equalizing circuit with the second output of said difference and equalizing circuit, an output of said second combining means carrying a modified right channel signal and being coupled to a second output of said circuit arrangement.
Applicant has found that by using simple matrixing and frequency response shaping, a wide degree of stereo spread may be achieved in which the perceived spread of the stereo signal is significantly wider than the actual placement of the loudspeakers. This is particularly advantageous in compact audio systems and television receivers in which there is a limited amount of separation between the left and right channel loudspeakers.
BRIEF DESCRIPTION OF THE DRAWINGS
With the above and additional objects and advantages in mind as will hereinafter appear, the invention will be described with reference to the accompanying drawings, in which:
FIG. 1 shows a schematic block diagram of the circuit of the subject invention;
FIG. 2 shows a schematic diagram of a first embodiment of the subject invention;
FIGS. 3-6 show response curves for various signals in the circuit of FIG. 2;
FIG. 7 shows a schematic diagram of a second embodiment of the invention;
FIGS. 8 and 9 show response curves for various signals in the circuit of FIG. 7;
FIG. 10 shows a schematic diagram of a modification of the circuit of FIG. 2; and
FIG. 11 shows response curves for various signals in the circuit of FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a basic schematic block diagram of the subject invention. A first and a second input 10 and 12 receive the left and right channel signals from a stereo signal source. The left channel signal is applied both to a first input of a summing and frequency equalizing circuit 14 and to a first input of a difference and frequency equalizing circuit 16. The right channel signal is similarly applied both to a second input of the summing and frequency equalizing circuit 14 and to a second input of the difference and frequency equalizing circuit 16. The summing and frequency equalizing circuit 14 adds the signals applied to its first and second inputs and then optionally performs a high frequency equalization on the combined signal (L+R). This combined signal is then supplied to a first and a second output of the summing and frequency equalizing circuit 14.
The difference and frequency equalizing circuit 16 forms a first difference signal (L-R) and a second difference signal (R-L). This circuit 16 then performs a frequency equalization, with respect to the response of the ear of a person on these difference signals to shape the response to simulate that which would be perceived by the if the sound sources (loudspeakers) were actually placed at virtual positions, i.e., wider and directly opposite the person's ears. The equalized first and second difference signals are then applied to first and second outputs of the difference and frequency equalizing circuit 16.
The first output of the summing and frequency equalizing circuit 14 is then combined with the first output of the difference and frequency equalizing circuit 16 forming a first output 18 of the circuit arrangement carrying a modified left channel signal. Similarly, the second output of the summing and frequency equalizing circuit 14 is combined with the second output of the difference and frequency equalizing circuit 16 forming a second output 20 of the circuit arrangement carrying a modified right channel signal.
FIG. 2 shows a schematic diagram of a first embodiment of the circuit arrangement of FIG. 1. The left channel input of the circuit is applied to a capacitor C1 and then through a resistor R1 to the inverting input of a first operational amplifier (OP-AMP) A1, through a resistor R2 to the inverting input of a second OP-AMP A2, and through a resistor R3 and a capacitor C2 to the inverting input of OP-AMP A3. The non-inverting input of OP-AMP A1 is connected to ground via a resistor R4.
The right channel signal is applied to a capacitor C3 and then through a resistor R5 to the inverting input of OP-AMP A4. A resistor R6 couples the inverting input to the output of OP-AMP A4, which is then coupled, through a resistor R7 to the capacitor C2 connected to the inverting input of OP-AMP A3.
The left channel signal at the output of capacitor C1 is also applied to a series arrangement of a resistor R8 and a capacitor C4 which, in combination with the right channel signal at the output of capacitor C3 after having passed through a resistor R9 coupling the right channel input to the inverting input of OP-AMP A1, on the one hand, and a series arrangement of a resistor R10 and a capacitor C5, is coupled to a resistor R11 connected to the output of OP-AMP A1. A voltage source Vcc is coupled to the circuit through a resistor R12. The resistor R12 is connected to ground via a capacitor C6, to the non-inverting input of OP-AMP A1, and to the non-inverting input of OP-AMP A4. The resistor R12 is further connected to the non-inverting inputs of OP-AMPs A2 and A3, and via a resistor R13 to capacitor C2. The output of OP-AMP A3 is connected to its inverting input via a resistor R14 and to capacitor C2 via a capacitor C7.
The output of OP-AMP A4 is also connected to the inverting input of OP-AMP A2 via a resistor R15 which is, in turn, connected to the output of OP-AMP A2 via the series arrangement of resistors R16 and R17, the junction between resistors R16 and R17 being connected to ground via a series arrangement of a capacitor C8 and a resistor R18, while the output of OP-AMP A2 is connected to ground via a series arrangement of a capacitor C9 and the resistor R18.
The output from OP-AMP A1 is connected via resistor R19 to the inverting input of OP-AMP A5, and via a resistor R20 to the inverting input of OP-AMP A6. The output from OP-AMP A3 is connected via a resistor R21 to the inverting input of OP-AMP A5, and via a resistor R22 to the non-inverting input of OP-AMP A6. The output of OP-AMP A2 is connected via resistor R23 to the inverting input of OP-AMP A5, and via resistor R24 to the non-inverting input of OP-AMP A6. Resistor R12, connecting to the voltage source Vcc, is connected to the non-inverting input of OP-AMP A5, and to the non-inverting input of OP-AMP A6 via a resistor R29.
The inverting input of OP-AMP A5 is connected to its output via a resistor R25, which is then connected through a capacitor C10 to ground via a resistor R26 and to the left channel output of the circuit. Similarly, the inverting input of OP-AMP A6 is connected to its output via a resistor R27, which is then connected through a capacitor C11 to ground via a resistor R28 and to the right channel output of the circuit.
In FIG. 2, OP-AMP A1 acts as the summing portion of circuit 14 of FIG. 1 for summing the left and right channel signals. OP-AMP A4 acts as an inverter for the right channel input signal, and a difference between the left and right channel signals being formed at the inverting input of OP-AMP A2. OP-AMP A2 operates as a mid-range human ear equalizer while OP-AMP A3 operates as a high-range human ear equalizer (parts of circuit 16 of FIG. 1). Finally, OP-AMPs A5 and A6 operate as a matrixing circuit for combining the (L+R) and (L-R), (R-L) signals thereby forming the left and right channel outputs.
FIG. 3 shows a response curve of the signal (L+R) at the output of OP-AMP A1 (which is applied to OP-AMP A5 and OP-AMP A6), while FIG. 4 shows a response curve of the signal (L-R) at the junction of resistors R21 (from OP-AMP A2) and R23 (from OP-AMP A3). FIG. 5 shows response curves of the left channel input and the left channel output of the circuit of FIG. 2, while FIG. 6 shows response curves of the left channel input and the right channel output of the circuit of FIG. 2.
FIG. 7 shows a second embodiment of the invention in which, instead of two separate tuned filters (equalizers) in the difference channel, the functions are combined by using a shelving circuit in conjunction with a peaked low-pass filter to achieve a response similar to that of FIG. 2.
In particular, the left channel input of the circuit is applied to a capacitor C50 and then through a series arrangement of resistors R50 and R51 to the non-inverting input of OP-AMP A50, this non-inverting input being coupled to ground through a capacitor C60. The left channel signal at the output of capacitor C50 is also applied to a parallel arrangement of a resistor R52 and a capacitor C51, and then to a resistor R53 which is connected to the non-inverting input of OP-AMP A51.
The right channel input of the circuit is applied to a capacitor C52 and then through a resistor R54 to the junction between resistors R50 and R51. The right channel signal at the output of capacitor C52 is also applied to a parallel arrangement of a resistor R55 and a capacitor C53, and then to a resistor R56 which is connected to the inverting input of OP-AMP A51. A resistor R57 connects the output of OP-AMP A50 to its inverting input, while a resistor R58 connects the output of OP-AMP A51 to its inverting input.
The non-inverting input of OP-AMP A51 is connected, through a series arrangement of resistors R59 and R60, to the inverting input of OP-AMP A50, the junction between resistors R59 and R60 being connected to a voltage source Vcc via a resistor R61, and to ground via a parallel arrangement of a resistor R62 and a capacitor C54.
The output of OP-AMP A51 is connected via a series arrangement of resistors R63 and R64 to the non-inverting input of OP-AMP A52, this non-inverting input also being connected to ground via a capacitor C55. The output of OP-AMP A52 is connected to its inverting input, to the junction of resistors R63 and R64 via a capacitor C56, and to the inverting input of OP-AMP A53 via a resistor R65. The output of OP-AMP A50 is connected to the junction between resistors R50 and R51 via a capacitor C57, to the non-inverting input of OP-AMP A53 via a resistor R66, and to the left channel output of the circuit via a series arrangement of a resistor R67 and a capacitor C58, this left channel output being connected to ground by a resistor R68. The output of OP-AMP A52 is further connected to the junction between resistor R67 and capacitor C58 via a resistor R69. The junction between resistors R59 and R60 is also connected to the non-inverting input of OP-AMP A53 via a resistor R70.
Finally the output of OP-AMP A53 is connected to its inverting input via a resistor R71, and to the right channel output of the circuit via a capacitor C59, this right channel output being connected to ground via a resistor R72.
The left and right channel signals are summed at the junction of resistors R50 and R54 and then applied to the non-inverting input of OP-AMP A50 which then performs the high frequency equalization on the summed signal. The left and right channel signals are also applied to the non-inverting and inverting inputs, respectively, of OP-AMP A51 via R52, R53, R55, R56, C51 and C53, which forms the difference of these signals. The output of OP-AMP A51 is applied to OP-AMP A52 which, in combination with the resistors and capacitors connected thereto, performs the peaked low-pass filtering of the difference signal (i.e., the human ear equalization). This processed difference signal (L-R) is combined with the output (L+R) from OP-AMP A50 and the combined signal forms the left channel output of the circuit. In addition, the output from OP-AMP A52 (L-R) is applied to the inverting input (effectively forming R-L) of OP-AMP A53 while the output from OP-AMP A50 (L+R) is applied to the non-inverting input of OP-AMP A53, whose output thus forms the right channel output of the circuit.
FIG. 8 shows response curves of the left channel input and the left channel output of the circuit of FIG. 7, while FIG. 9 shows response curves of the left channel input and the right channel output of the circuit of FIG. 7.
FIG. 10 shows a schematic diagram of another embodiment of the invention which, in effect, is a modification of the circuit of FIG. 2. In particular, the left channel input of the circuit is applied to a capacitor C100 and then through a series arrangement of resistors R100 and R101 to the non-inverting input of OP-AMP A100, this non-inverting input being connected to ground by a capacitor C101. The left channel input of the circuit from capacitor C100 is also applied via a resistor R102 to the inverting input of OP-AMP A101.
The right channel input is applied to a capacitor C102 and then through a resistor R103 to the junction between resistors R100 and R101. The right channel signal at the output of capacitor C102 is also applied via a series arrangement of resistors R104, R105 and R106 to the inverting input of OP-AMP A102. The output from OP-AMP A101 is connected to its inverting input by a resistor R107, and to the junction between R104 and R105 by a resistor R108. This junction is connected to ground by a series arrangement of a capacitor C103 and a resistor R109. The junction between resistors R105 and R106 is connected to the junction between capacitor C103 and resistor R108 by a capacitor C104, and is also connected to the inverting input of OP-AMP A102 by a capacitor C105.
The output of OP-AMP A102 is connected to its inverting input by a series arrangement of a resistor R110 and a capacitor C106, this series arrangement being in parallel with a resistor R111. The output of OP-AMP A102 is further connected to the non-inverting input of OP-AMP A103 by a series arrangement of resistors R112 and R113.
The output from OP-AMP A100 is connected to its inverting input, to the junction of resistors R100 and R101 via a capacitor C107, to the non-inverting input of OP-AMP A104 via a resistor R114, and to the non-inverting input of OP-AMP A105 via a resistor R115. The output of OP-AMP A103 is connected to its inverting input, to the non-inverting input of OP-AMP A104 via a resistor R116, and to the inverting input of OP-AMP A105 via a resistor R117.
A voltage source Vcc is applied to a resistor R118 and through a parallel combination of a resistor R119 and a capacitor C108 to ground. The junction between the resistor R118 and the parallel combination is connected to the inverting input of OP-AMP A104 via a resistor R120, to the non-inverting input of OP-AMP A105 via a resistor R121, to the non-inverting input of OP-AMP A103 via a capacitor C109, and to the non-inverting inputs of OP-AMPs A102 and A101.
The output from OP-AMP A104 is connected to its inverting input via a resistor R122 and to the left channel output of the circuit via a capacitor C110, this left channel output being connected to ground by a resistor R123. Similarly, the output from OP-AMP A105 is connected to its inverting input via a resistor R124, and to the right channel output of the circuit via a capacitor C111, this right channel output being connected to ground by a resistor R125.
The left and right channel signals are summed at the junction of resistor R100 and R102 and are subjected to high frequency equalization by OP-AMP A100 thus forming the processed sum signal (L+R). The left channel signal is inverted in OP-AMP A101 and is combined with the right channel signal at the junction of resistors R104 and R108 which is then subjected to the mid- and high- range equalization (human ear equalization) by the OP-AMPs A102 and A103. The output of OP-AMP A103, carrying the modified difference signal (L-R), is combined with the output from OP-AMP A100, carrying the modified sum signal (L+R) and is processed in OP-AMP A104 thereby forming the left channel output. The output of OP-AMP A103 is also applied to the OP-AMP A105 along with the output of OP-AMP A100 which forms at its output the right channel signal.
FIG. 11 shows response curves of the left and right channel outputs as well as the separation between the two channels.
The values of the circuit components used in FIGS. 2, 7 and 10 are as follows:
______________________________________FIG. 2RESISTORS VALUE (in ohms)______________________________________R1 39KR2, R8, R10, R15, R27, R29 22KR3, R5, R6, R7, R21, R22 10KR4, R12, R13 1KR9, R11, R20 39KR14 100KR16 27KR17 12KR18, R19 13KR23, R24 15KR25 7.5K______________________________________CAPACITORS VALUE______________________________________C1, C3, C10, C11 5 μFC2, C7, C9 .0022 μFC4, C5 820 PFC6 100 μFC8 .033 μF______________________________________FIG. 7RESISTORS VALUE (in ohms)______________________________________R50, R54 22KR51 12KR52, R53, R55, R56, R63 10KR57 47KR58, R59 30KR60 33KR61, R62 1KR64 6.8KR65, R66 39KR67, R69 4.7KR68, R72 100KR70, R71 20K______________________________________CAPACITORS VALUE______________________________________C50, C52, C58, C59 5 μFC51, C53 .068 μFC54 100 μFC55 330 PFC56 .015 μFC57 1200 PFC60 1000 PF______________________________________FIG. 10RESISTORS VALUE (in ohms)______________________________________R100, R103 12KR101, R112, R113 15KR102, R104, R107, R108, R114, 10KR115, R116, R117, R120, R121,R122, R124R105 5KR106, R111 68KR109 750R110 27KR118, R119 1KR123, R125 100K______________________________________CAPACITORS VALUES______________________________________C100, C102, C110, C111 5 μFC101 390 PFC103, C104 22 NFC105 33 NFC106 750 PFC107 15 NFC108 100 μFC109 120 PF______________________________________
Numerous alterations and modifications of the structure herein disclosed will present themselves to those skilled in the art. However, it is to be understood that the above described embodiment is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. | By using special frequency response manipulation in the difference channel of a stereo signal, the stereo image will appear to extend beyond the actual placement of the loudspeakers. This is accomplished by shaping the difference channel response to simulate the response one would be subjected to if the sources were physically moved to the virtual positions. The circuit includes a summing and high frequency equalization circuit to which the left and right stereo signals are applied, and a difference forming and human ear equalization circuit also to which the left and right stereo signals are applied. The outputs from these circuits are cross-coupled to form left and right channel outputs. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This patent application claims the priority and is a continuation-in-part of U.S. patent application Ser. No. 12/103,027 filed Apr. 15, 2008 which is incorporated by reference herein in its entirety.
FIELD OF THE INVENTION
[0002] The invention relates to apparatus and methods for determining parameters representative of formation properties and formation fluid properties of subterranean reservoirs, particularly hydrocarbon reservoirs. More specifically, the invention relates to apparatus and methods for measuring formation parameters at the location of an induced flow in the formation.
BACKGROUND
[0003] In the course of assessing and producing hydrocarbon bearing formation and reservoirs, it is important to acquire knowledge of formation and formation fluid properties which influence the productivity and yield from the drilled formation. Typically such knowledge is acquired by methods generally referred to as “logging”.
[0004] Logging operations involve the measurement of a formation parameter or formation fluid parameter as function of location, or more specifically depth in a wellbore. Formation logging has evolved to include many different types of measurements including measurements based on acoustic, electro-magnetic or resistivity, and nuclear interactions, such as nuclear magnetic resonance (NMR) or neutron capture.
[0005] NMR measurements are commonly used in the wellbore to probe the NMR decay behavior of the stationary fluid in the reservoir rock. During these measurements, magnetic fields are established in the formation using suitably arranged magnets. The magnetic fields induce nuclear magnetization, which is flipped or otherwise manipulated with on-resonance radio frequency (RF) pulses. NMR echoes are observed, and their dependence on pulse parameters and on time is used to extract information about the formation and the fluids in it.
[0006] In particular, NMR has been used in the oilfield industry to obtain information and parameters representative of bound fluids, free fluids, permeability, oil viscosity, gas-to-oil ratio, oil saturation and water saturations. All these parameters can be derived from measurements of spin-spin relaxation time, often referred to as T2, spin-lattice relaxation time (T1), and self-diffusion coefficient (D) of the molecules containing hydrogen contained in formation fluids.
[0007] On the other hand, fluids are routinely sampled in the well bore with the help of so-called formation testers or formation fluid sampling devices. An example of this class of tools is Schlumberger's MDT™, a modular dynamic fluid testing tool. Such a tool may include at least one fluid sample bottle, a pump to extract the fluid from the formation or inject fluid into the formation, and a contact pad with a conduit to engage the wall of the borehole. When the device is positioned at a region of interest, the pad is pressed against the borehole wall, making a tight seal and the pumping operation begins.
[0008] With the pumping a flow in the formation is induced by extracting fluid from the formation through the conduit. The fluid flowing through the tool is analyzed in situ using electrical, optical or NMR based methods. Typically when the fluid is assumed to be ‘pure’ reservoir fluid, i.e., when having acceptable levels of mud or other contaminants, a sample of the fluid is placed into the sample bottle for later analysis at a surface laboratory. The module is then moved to the next region of interest or station.
[0009] Fluid flow into the borehole is also routinely produced using dual packer arrangements, which for example isolate sections of the borehole during fluid and pressure testing, essentially in the same manner as described for the MDT tool described above. By reversing the flow direction dual packer arrangements offer the possibility of conducting fracturing operations which are designed to fracture the formation around the isolated section of the borehole.
[0010] When specifically attempting to inject rather than extract fluid from the formation, a testing tool may require modifications such as described for example in the co-owned U.S. Patent Application 2006/0000606. The tool described therein is a formation tester for open hole formations incorporating a drill bit to drill through the mudcake which accumulates on the wall of the well bore or through zones damaged or contaminated by the drilling process. The tool as described in U.S. 2006/0000606 is capable of injecting fluid into the formation surrounding wellbore for various purposes such as fracturing the formation near the wellbore.
[0011] It is further well established to mount logging tools on either dedicated conveyance means such as wireline cables or coiled tubing (CT) or, alternatively, on a drill string which carries a drill bit at its lower end. The latter case is known in the industry as measurement-while-drilling (MWD) or logging-while-drilling (LWD). In MWD and LWD operations the parameter of interest is measured by instruments typically mounted close behind the bit or the bottom-hole assembly (BHA). Both, logging in general and LWD are methods known as such for several decades and hence are believed to require no further introduction.
[0012] Applications and measurements designed to exploit the flow generated by tools such as the above formation testing tools in combination with NMR type measurements are described in a number of documents. One example of these published documents is the co-owned U.S. Pat. No. 7,180,288 to Scheven. Another detailed description of possible NMR-based methods for the purpose of monitoring flow and formation parameters can be found in the co-owned U.S. Pat. No. 6,642,715 to Speier et al. and U.S. Pat. No. 6,856,132 to Appel et al. A tool which combines a fluid injection/withdrawal tool with a resistivity imaging tool is described for example in the co-owned U.S. Pat. No. 5,335,542 to Ramakrishnan et al. Borehole tools and methods for measuring permeabilities using sequential injection of water and oil is described in the co-owned U.S. Pat. No. 5,269,180 to Dave and Ramakrishnan and in the co-owned U.S. Pat. No. 7,221,158 to Ramakrishnan. In the co-owned U.S. Pat. No. 5,497,321 to Ramakrishnan and Wilkinson, the authors suggest a method to compute fractional flow curves using resistivity measurements at multiple radial depths of investigation.
[0013] In a paper prepared for presentation at the SPWLA 1st Annual Middle East Regional Symposium, Apr. 15-19, 2007, Gilles Cassou, Xavier Poirier-Coutansais and one of the inventors of the present invention, Raghu Ramamoorthy, demonstrate that the combination of advanced-NMR fluid typing techniques with a dual-packer fluid pumping module can greatly improve the estimation of the saturation parameter in carbonate rocks. The ability to perform 3D-NMR stations immediately before and after pump-outs yields both the water and oil saturations (Sw,Sxo) independently of lithology, resistivity, and salinity, in a complex carbonate environment.
[0014] However, the method as demonstrated suffers from a number of limitations which makes it difficult to conduct reliable and accurate measurements. Both tools have to be accurately positioned at the same depth at different times. The two 3D-NMR acquisitions must be performed at exactly the same depth as the sampling operation for the manipulation of the formation to be reflected in the 3D-NMR measurement. Given that both tools need to be moved up and down the wellbore to position them correctly—and given further that the uncertainty in tool positioning is at least as large as the dimensions of a typical NMR antenna—the tested implementation as described is not optimal. Moreover, operational problems dictate that the tests cannot be performed by the probe directly because it becomes then more difficult to ensure that the NMR antenna is positioned exactly over the test interval, instead the dual packer configuration has to be used.
[0015] Furthermore, the time to unset the dual packers and move the NMR tool down to the correct position at the test interval is about 10 minutes. A typical 3D-NMR measurement may require another 15 minutes of time at the station. If significant re-invasion occurs during this time, the post-pumpout 3D-NMR data is affected and can no longer be correlated with the flow regime as induced by the tool.
[0016] In view of the known art, it is therefore seen as one object of the invention to improve and enhance known apparatus and methods for characterizing formations using induced flow in the formation. It is seen as another object to provide more and better methods of determining characteristic formation and formation fluid properties using measuring apparatus having a volume of investigation overlapping or co-located with the volume in which induced flow occurs.
SUMMARY OF INVENTION
[0017] According to a first aspect of the invention, tools and method for measuring a parameter characteristic of a rock formation are provided, including having in a section of a well penetrating the rock formation a device for generating a sensing field in a measuring volume within the rock formation and a device for causing a flow through the measuring volume, preferably in the presence of the sensing field, and sensors responsive to changes in the sensing field, wherein sensor responses are indicative of the amounts of fluid in the measuring volume in different states of the flow, preferably including a state before the generated flow affects the measuring volume and a state after onset of the flow through the measuring volume.
[0018] An amount of fluid is defined for the purpose of the invention to include parts or percentages of formation fluid which consists of hydrocarbon and/or parts or the percentage which consists of water. In the industry, two of the most utilized of such parameters are often referred to as hydrocarbon saturation (Shc) or oil saturation (So) and water saturation (Sw), respectively.
[0019] In a variant of these embodiments, a fluid is either withdrawn or more preferably injected into the formation to sweep away the hydrocarbon and obtain a measure of the residual oil saturation (ROS) with the subsequent measurements. In an alternative variant, a hydrocarbon-based fluid such as formation crude oil can be injected into the formation to estimate the amount of the residual water saturation (Swr). Both parameters, ROS and Swr are important end-points in the determination of the relative permeabilities relations as a function of saturation and can thus be ultimately used to determine a measure of the recovery factors for the reservoir.
[0020] In a further variant of this embodiment, the saturation of a phase in the formation and flow rates or cuts of fluid phases are measured. Knowledge of the flow volumes or fractional flows in dependence of the saturation can be used to derive directly the relative permeability of a phase in the formation.
[0021] The invention further contemplates the use of a sensing field based on any of the known logging measurement which can sense the change of a parameter within the formation, including sonic, acoustic, magnetic and electro-magnetic sensing fields. Hence the sensors are preferably responsive to one of these types of fields and register electro-magnetic signals, resistivity signals, dielectric signals, NMR signals and neutrons capture. In an even more preferred variant, the sensors register any such signals at multiple depths as measured in radial direction from the well. In a preferred embodiment, the sensing field comprises a magnetic field. In a variant of this embodiment, distributions of the spin-lattice relaxation or T1 distributions or distributions of spin-spin relaxation (T2) are derived from the sensor response. However, for the in situ measurements of the time-evolution of a parameter, faster methods based for example on induction or resistivity arrays may be preferred making hence use of tools such as the resistivity imaging tool described in U.S. Pat. No. 5,335,542.
[0022] In a preferred variant of the NMR based methods, magnetic resonance fluid (MRF) characterization is applied to the sensor response. Magnetic resonance fluid (MRF) characterization is a multi-sequence NMR acquisition where polarization time and echo spacing are varied resulting in a sensitivity to diffusion and T1 and T2 distributions. MRF measurements can be used to measure both Sw and So in carbonates independent of lithology, resistivity and salinity.
[0023] The capability to perform and compare two or more MRF measurements in a time-lapse manner before and after an induced flow reduces some of the uncertainties caused by the drilling process and formation invasion. Invasion of drilling fluid filtrate changes the fluid composition near the wellbore. Flowing from the formation into the tool has the effect of replacing filtrate with formation fluid, thus placing the measuring volume in the formation into a state much closer to the original formation. Controlled injection of a known fluid on the other hand can be used advantageously to create a zone which is more completely flushed than by merely the uncontrolled and unmonitored invasion of mud filtrate.
[0024] While it is possible to generate flow by any tool which is capable of causing a pressure gradient across the surface of the well, the present invention employs preferably tools and method which are coupled with means to determine flow related parameters. Preferred tools are therefore variants of the known formation sampling tools modified such that the sensing tool can project its sensing field into the volume of the formation subject to the flow caused by the sampling tool.
[0025] Typically the flow is caused by engaging the wall of the well with a probe of the sampling tool and using a pumping mechanism to withdraw fluid from the formation. However, in a further embodiment of the invention the flow can be alternatively or alternatingly caused by injecting a fluid into the formation. In this embodiment of the invention, the parameter can be measured while having a flow into and out of the formation.
[0026] In another aspect of the invention, the monitored amounts of fluids in the formation can be analyzed for compositional changes in the hydrocarbon phase as caused by the flow. Again, it is a preferred embodiment of this aspect of the invention to repeat stationary measurements under different flow conditions, i.e. before, during and after the induced flow.
[0027] In a preferred embodiment of this aspect of the invention, the amount or total volume of hydrocarbon in a measuring volume within the formation is decomposed in accordance with the values of a parameter which can be derived from the measurement. It can be observed that these fractioned or decomposed parts of the hydrocarbon behave differently under different flow conditions. Such measurements can therefore lead to parameters related to the composition of the formation fluid. In a variant of this embodiment, this parameter is the T1 or T2 distribution or a parameter derivable from these distributions, such as viscosity. Observing the reservoir fluid decomposed according to such a parameter allows for better estimates of recoverable reserves and/or the effectiveness of enhanced oil recovery (EOR) treatments.
[0028] In accordance with a further aspect of the invention, the method can be used to determine the effectiveness of enhanced oil recovery in various manners. Enhanced oil recovery (EOR) methods include the injection of specialized chemical compounds such as surfactants or water blocking gels into the formation. EOR methods also include thermal-based reservoir treatments such as steam or gas injections. By monitoring the reaction of the fluid in the measuring volume within the formation, it is possible to estimate the efficacy of such an EOR treatment on a larger reservoir scale. In an embodiment of this aspect of the invention, the effectiveness of chemicals, such as surfactants, when injected into the formation can be monitored in situ and evaluated accordingly to derive further important parameters such as effective hydrocarbon recovery factors with and without the treatment.
[0029] Further details, examples and aspects of the invention will be described below referring to the drawings listed in the following.
BRIEF DESCRIPTION OF THE FIGURES
[0030] FIG. 1A illustrates a conventional drilling operation;
[0031] FIG. 1B illustrates a logging operation in accordance with an example of the present invention;
[0032] FIGS. 2A and 2B show a schematic frontal and a cross-sectional view of a tool for use in the present invention;
[0033] FIG. 3 shows a schematic cross-sectional view of another tool for use in the present invention;
[0034] FIG. 4A illustrates a typical measurement as performed by an NMR tool;
[0035] FIGS. 5A and 5B illustrates interpretations enabled by the present invention; and
[0036] FIG. 4B shows another possible measurement based on the present invention.
DETAILED DESCRIPTION
[0037] In FIG. 1A , a well 11 is shown in the process of being drilled through a formation 10 . A drill string 12 is suspended from the surface by means of a drilling rig 13 . A drill bit 12 - 1 is attached to the bottom of the drill string 12 .
[0038] While drilling, a drilling fluid is circulated through the drill string 12 and the drill bit 12 - 1 to return to the surface via the annulus between the wall of the well 11 and the drill string 12 . During this process, part of the drilling fluid invades a shallow zone 15 around the borehole 11 thus contaminating the formation fluid.
[0039] After completing the drilling through a hydrocarbon bearing formation, a wireline tool 16 as shown in FIG. 1B is lowered into the well 11 using a wireline cable 17 . In the example as illustrated, the wireline tool includes a formation testing device 16 - 1 to be used for generating a flow in the formation and an NMR-based tool 16 - 2 with a combination of permanent magnets and antennas (not shown) to generate a magnetic field within the volume of the formation affected by the flow. Such tools have been described in the prior art, including the co-owned U.S. Pat. No. 7,180,288 to Scheven, the co-owned U.S. Pat. No. 6,642,715 to Speier et al., and the U.S. Pat. No. 6,856,132 to Appel et al.
[0040] A further variant of such a tool is illustrated in FIGS. 2A and 2B showing a frontal and cross-sectional view, respectively, of the schematics of a combined sampling and NMR tool.
[0041] The body 20 of the downhole logging tool includes a sampling probe taking the shape of a pad 21 . The pad 21 includes an outer zone 211 of magnetic material behind a sealing layer of elastic material. The magnetic material of this example is permanently magnetic and can hence generate a magnetic field in those parts of the formation which face the probe. An inner zone of the pad 21 includes an antenna area 212 and the flowline 213 . A feed circuit 22 to power and control the antenna is located behind the pad 21 . The flowline includes a flowmeter Q similar to the known devices.
[0042] The antenna is designed to deliver NMR pulses 23 into the formation. The tool as illustrated is in a state of injecting fluid from the tool body 20 into the formation 10 . In other states, fluid may flow in reverse direction, i.e., from the formation 10 into the flowline 213 . The tool shown is distinguishable from known designs of combined sampling and NMR tools by having the antenna 212 in a recessed area of the pad 21 . It is seen as a novel aspect of such designs to have the recessed area act effectively like a funnel, thus drawing in or injecting flow from a bigger effective area and in turn enlarging the measuring volume where flow and magnetic field overlap. The recessed area serves further to protect the antenna from the impact and sealing forces acting when the pad makes contact with the formation.
[0043] For an electro-magnetic or resistivity-based measurement, the combination of an NMR tool and formation testing tool as shown above can be replaced by a combination of resistivity array tool and formation testing tool. Such a tool is described for example in the co-owned U.S. Pat. No. 5,335,542 to Ramakrishnan et al. Other sensing fields require a corresponding change of the type of source and receivers in the tool body. However for most of the known sensing fields whether acoustic, sonic or electromagnetic, corresponding logging tool designs exists and can be thus adapted to methods and tools described herein.
[0044] Integrated into the flowline of the sampling tool are typically further measuring devices (not shown), such as optical, NMR, or resistivity based sensors etc., to measure composition-related parameters of the sampled or ejected flow inside the tool. These devices include also flowmeters Q to determine the total flow Qw+Qo and the water flow Qw and the hydrocarbon flow Qo. The flowline 213 is further connected to a flow generator or pump (not shown) located within the body of the logging tool. The flow generator is designed to move fluids from the formation into the body of the tool or from a storage tank (not shown) within the body of the tool into the formation.
[0045] A wireline suspended dual packer tool suitable for performing measurements in accordance with another example of the invention is shown in FIG. 3 . The tool 31 of FIG. 3 is suspended from a wireline 32 into an open hole. It has a pair of packers 33 with integrated arrays of sensors 34 . The sensors can be designed as an array of electrodes, antennas gamma-ray receivers or emitters etc. depending on the measurement to be performed. The pair of packers isolates a zone 30 of the formation. The tool further comprises a fluid reservoir chamber 35 connected to the fluid ports 361 via a flow line 36 . The flow through the flow line 35 is driven by a pumping module 37 . The pumping module can be designed to support flow from the formation into the reservoir chamber or from the chamber into the formation. Depending on the type of experiment to be performed, the chamber may contain sample fluids such as water or oil, or solutions of active chemicals to modify the formation, the formation fluids, or the response of the formation or formation fluid to the sensing field. The lines 38 and 39 provide an electrical connection and a hydraulic connection, respectively, to the packer 33 and the sensors 34 .
[0046] It is important to note that the measurement as proposed in the present invention will result in a response signal from the fluid as located inside the measuring volume and hence inside the formation. Previous efforts of combining NMR and a sampling tool have mostly focused on measuring the properties of the sampled fluid or its velocity after it leaves the formation and moves through the flow line of the tool. In the present invention, the sampling tool is employed as a means to generate a flow in the formation. This flow changes the values of parameters associated with the formation whilst leaving others unchanged. It has been observed that by recording such changes, parameters of great importance for the characterization of the formation can be determined with potentially much higher accuracy, revealing even previously unknown aspects.
[0047] In a first example of an embodiment of the invention, the oil and water saturations of the formation fluids are determined as a function of the flow rate. The saturations can be determined for example by evaluating measured T1 or T2 distribution curves. To illustrate the principle of the evaluation, a simplified example of such curves is shown in FIG. 4A . The water signal is shown as a solid line 41 and oil as a dashed line 42 . Saturations can be determined from such a measurement by calculating the ratio of the relative areas under the curves to the total area.
[0048] The response of the formation to many measurements, including the NMR type measurement above, can be modified through injection of a suitable chemical. Using for example either MnCl2 or NiCl as part of any injected fluid reduces the water response signal or, at the very least, shifts it to very short T2 values. This effect results in a clear separation between the water and oil signals in the T2 domain and the residual oil saturation estimation becomes a simple volumetric determination based on the measured T2 distribution.
[0049] Whilst the example as illustrated is simplified in order to make important aspects more transparent, it is expected that real measurements are based on more advanced methods of evaluating NMR data such as MRF methods or other any known method to acquire and interpret three dimensional (3D) NMR data. For details of the theory and implementation of the MRF method, reference can be made to Freedman, R., Sezginer, A., Flaum, M., Matteson, A., Lo, S., and Hirasaki, G. J.: “A New NMR Method of Fluid Characterization in Reservoir Rocks: Experimental Confirmation and Simulation Results,” SPE 63214, Transactions of the 2000 SPE Annual Technical Conference and Exhibition, Dallas, Tex., USA, 1-4 Oct. 2000.
[0050] With the saturation values determined using either the NMR based methods as described in the above example or measurements based on other sensing fields, the flowmeter Q can be used to measure the water cut or flow Qw and/or the hydrocarbon cut or flow Qo of the sampling tool. The term “cut” is used to indicated the amount of a single phase in what is typically a multiphase flow produced from the borehole.
[0051] If required, the time lag between the flow measurements and the saturation measurements can be compensated for by for example calculating the average flow velocity between the location of the saturation measurement and the flowmeter location inside the tool body. Another way of performing such compensation may include using correlations between the NMR measurements and the flowmeter and selecting the time lag which maximizes such correlations. The compensation ensures that the measurement as performed by the flowmeter reflects the composition of the flow as it passes through the measuring volume of the NMR tool for evaluation.
[0052] In a preferred embodiment of the invention the measured saturations and flow rates are matched to fit a relations or model which includes the relative permeabilities k(ro) or k(rw). In principle all measured points lie on curves such as shown in FIG. 5A .
[0053] In FIG. 5A , there are shown the relative permeability kro of hydrocarbon as a function of saturation and the relative permeability krw of water as a function of saturation. The endpoints of both curves are defined by the residual water saturation Swr and the residual hydrocarbon saturation ROS. Based on the current knowledge of the theory of this relation, it is in many cases not required to determine more than two points to derive a useful estimate of a relative permeability curve. These two points could be the permeability at the residual water saturation Swr and the residual hydrocarbon saturation ROS. However the accuracy of such an estimate or model is increased by determining more measurements points on the curves. A further, more detailed example of a model based approach for evaluating saturation measurements to derive relative permeabilities is described in: “Water-cut and fractional-flow logs from array-induction measurements” by T. S. Ramakrishnan and D. J. Wilkinson, 1999 SPE Reservoir Evaluation and Engineering 2 (1), pp. 85-94.
[0054] Once the relative permeabilities krw(Sw) and kro(Sw) are established as functions of the saturation, it is possible to derive the fractional flow using for example equation [1] below with μw being the μw and
[0000] fw ( Sw )=( krw ( Sw )/μ w )/( krw ( Sw )/μ w+kro ( Sw )/μ o ) [1]
[0000] resulting in curves for the fractional flowrates as a function of the saturation as shown for the flowrate fw(Sw) of the water phase in FIG. 4B . Once established, this function can be used to determine important parameters. For example, a measure of the recoverable oil in the formation can be derived by measuring the actual saturations and their respective distance to the endpoints of the saturation curves indicating the residual oil or water saturations.
[0055] In another example of the invention, the T1 or T2 distributions as shown in FIG. 4A can be recorded as a function of time and hence as a function of the flow which passed through the monitored formation volume. The benefit of such a measurement can be demonstrated by comparing the schematic FIGS. 4A and 4B . The latter figure shows the same measuring volume but after an injection of water.
[0056] The measured distribution gives an indication of the residual oil saturation ROS by evaluating the area of the “oil peak”, which is reduced after the injection of water from the tool as described above. However apart from the determination of saturations, the distribution can further be evaluated to make determinations as to the composition of the hydrocarbon.
[0057] It is generally known that the absolute value of T1 or T2 can be linked to fluid related parameters such as viscosity. Hence each value of T1 (or T2) is taken in this example as a value representative of viscosity.
[0058] In FIGS. 4A and 4B , which together illustrates the case of a composition change in the formation fluid due to a water injection, the oil peak is not only reduced in amplitude, but the amplitude reduction in FIG. 4B relative to the original amplitudes of FIG. 4A differs for different values of T1. In the illustrated example, the composition of the formation oil has changed, with the low viscosity fractions of the oil (at higher T1 values) being apparently flushed more effectively from the formation than the higher viscosity fractions. The higher viscosity portion of the formation oil remains in place and forms a relatively larger fraction of the residual oil which cannot be produced by water injection or flush alone.
[0059] To observe compositional changes such as described in the example above provides important information to assist in decisions concerning the methods chosen at various stages in the life of the reservoir to recover its hydrocarbon content. It can also be used in determining the most efficient form of EOR treatment. If, for example, the recoverable oil left in the formation is more viscous than the produced oil, EOR treatments will need to be planned differently taking into account the change in the viscosity of the remaining oil.
[0060] Apart from drawing conclusions on the efficacy of types of EOR treatments, it is further possible to measure the effects of such a treatment on a very small scale but within a very short time period. Repeating the injection measurements as described above with an EOR treatment fluid rather than water, it is possible to monitor directly the changes in the formation, in particular the residual oil saturation without and with the EOR treatment tested. When testing a chemical based method, the relevant chemical components can be mixed to the internal fluid flow inside the tool. If a heat treatment is contemplated for testing, the fluid injected can be heated inside the tool body prior to injection into the formation. Thus the invention can provide a very fast screening method for a wide variety of existing and future EOR treatments which would otherwise take months or even years to test.
[0061] Although only a few example embodiments have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from this invention. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, where as a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words “means for” together with an associated function. | An apparatus and method of measuring a parameter characteristic of a rock formation in an oil well is provided with a device for generating a sensing field within a volume of the rock formation and a device for causing a flow through the volume in the presence of the sensing field, further including sensors responsive to changes in the volume, wherein a sensor response is indicative of the amounts of fluid, particularly hydrocarbon and water saturations and irreducible hydrocarbon and water saturations. Measurements can be made before the flow affects the measuring volume and after onset of the flow through the measuring volume. | 4 |
FIELD
[0001] The present disclosure relates generally to implants, and particularly to a method and apparatus for a knee implant.
BACKGROUND
[0002] The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
[0003] Many portions of the human anatomy naturally articulate relative to one another. Generally, the articulation between the portions of the anatomy is substantially smooth and without abrasion. This articulation is allowed by the presence of natural tissues, such as cartilage and strong bone.
[0004] Over time, however, due to injury, stress, degenerative health issues and various other issues, articulation of the various portions of the anatomy can become rough or impractical. For example, injury can cause the cartilage or the boney structure to become weak, damaged, or non-existent. Therefore, the articulation of the anatomical portions is no longer possible for the individual.
[0005] At such times, it can be desirable to replace the anatomical portions with a prosthetic portion such that normal or easy articulation can be reproduced. A distal end of a femur naturally articulates with respect to a tibia to form a knee joint. After injury or other degenerative processes, the distal end of the femur and the tibia and can become rough or damaged. Therefore, it can be desirable to replace the distal end of the femur and the tibia with a prosthesis.
SUMMARY
[0006] A prosthesis for replacing an articulating portion of bone. The prosthesis can include an adaptor operable to replace a portion of the bone. The prosthesis can further include a sleeve coupled to the adaptor. The sleeve can define an offset coupling axis. The prosthesis can also include an articulating portion operable to replace the articulating portion of the bone. The sleeve can be positionable to couple the articulating portion relative to the offset coupling axis at a predetermined orientation.
[0007] Provided is a prosthesis for replacing an articulating portion of bone. The prosthesis can include an adaptor operable to replace a portion of the bone. The adaptor can define an offset coupling axis. The prosthesis can also include an articulating portion operable to replace the articulating portion of the bone. The articulating portion can be adapted to be coupled to the offset coupling axis. The adaptor can be composed of a porous metal material.
[0008] A prosthesis for replacing an articulating portion of bone is further provided. The prosthesis can include an adaptor operable to replace a portion of the bone. The adaptor can include a surface, an apex and at least one sidewall. The sidewall can couple the surface to the apex. The prosthesis can further include an articulating portion operable to replace the articulating portion of the bone. The articulating portion can be adapted to be coupled to the adaptor. The prosthesis can also include at least one augment coupled to at least a portion of the sidewall of the adaptor. The adaptor and the augment can be composed of a porous metal material.
[0009] Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
[0010] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
[0011] FIG. 1 is a perspective view of a knee implant according to the present disclosure;
[0012] FIG. 1A is a cross-sectional view of the knee implant of FIG. 1 , taken along line 1 A- 1 A of FIG. 1 ;
[0013] FIG. 2 is a cross-sectional view of the knee implant of FIG. 1 taken along line 2 - 2 of FIG. 1 , illustrating the knee implant of FIG. 1 engaged with a selected portion of the anatomy;
[0014] FIG. 2A is a perspective view of a first alternative knee implant according to the present disclosure;
[0015] FIG. 2B is a perspective view of a second alternative knee implant according to the present disclosure;
[0016] FIG. 3 is an exploded view of the knee implant of FIG. 1 ;
[0017] FIG. 3A is a front view of the knee implant of FIG. 3 ;
[0018] FIG. 4 is an environmental view of a first procedure for coupling the knee implant to the selected portion of the anatomy;
[0019] FIG. 5 is an environmental view of a second procedure for coupling the knee implant to the selected portion of the anatomy;
[0020] FIG. 6 is an environmental view of a third procedure for coupling the knee implant to the selected portion of the anatomy;
[0021] FIG. 7 is an environmental view of a fourth procedure for coupling the knee implant to the selected portion of the anatomy;
[0022] FIG. 8 is a perspective view of a third alternative knee implant according to the present disclosure;
[0023] FIG. 8A is a cross-sectional view of the third alternative knee implant of FIG. 8 , taken along line 8 A- 8 A of FIG. 8 ;
[0024] FIG. 9 is a cross-sectional view of the third alternative knee implant of FIG. 8 , taken along line 9 - 9 of FIG. 8 , illustrating the third alternative knee implant engaged with a selected portion of the anatomy;
[0025] FIG. 10 is an environmental view of a first procedure for coupling the third alternative knee implant of FIG. 8 to the selected portion of the anatomy;
[0026] FIG. 10A is a front view of the knee implant of FIG. 10 ; and
[0027] FIG. 11 is an environmental view of a second procedure for coupling the third alternative knee implant of FIG. 8 to the selected portion of the anatomy.
DETAILED DESCRIPTION
[0028] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. Although the following description is related generally to a prosthesis that can be positioned in a prepared portion of the anatomy, such as in a tibia or a femur, it will be understood that the prosthesis, as described and claimed herein, can be used with any appropriate surgical procedure. In addition, it should be noted that the knee implant of the present disclosure can be used in a revision knee implant procedure. Therefore, it will be understood that the following discussions are not intended to limit the scope of the appended claims.
[0029] As will be discussed in more detail herein, a knee implant assembly 6 is taught. With reference to FIGS. 1 , 1 A and 2 , the knee implant assembly 6 can include a femoral component 8 and a tibial component 10 , each of which can include an articulating portion. In one exemplary teaching, the tibial component 10 can include an articulating or mating portion 12 and an adaptor assembly 16 . It should be noted that as the knee implant assembly 6 can be used with any suitable knee prosthesis, such as a cruciate retaining knee prosthesis, for example, the AGC® Total Knee System™, a posterior stabilized knee prosthesis, for example, the AGC® Tradition High-Post Knee System™, or a hinged knee prosthesis, for example, the Orthopaedic Salvage System™, all provided by Biomet, Inc. of Warsaw, Ind., the mating portion 12 and femoral component 8 can be configured as needed for the particular surgical application. The tibial component 10 can also include a stem 18 and an augment system 20 both of which can be coupled to the adaptor assembly 16 . The mating portion 12 of the tibial component 10 can enable the femoral component 8 to articulate with respect to the tibial component 10 .
[0030] With particular reference to FIG. 2 , the femoral component 8 can be any generally known suitable femoral component 8 , and thus, the femoral component 8 need not be discussed in great detail herein. Briefly, however, the femoral component 8 can include an articulating portion or body 22 . The body 22 can be adapted to secure to a distal end of a femur 26 to enable the femur 26 to articulate with the tibial component 10 . The body 22 can include a first condylar portion 28 , a second condylar portion 30 and an intercondylar portion 32 . The first condylar portion 28 can define a first femoral bearing surface 34 , while the second condylar portion 30 can define a second femoral bearing surface 36 . The intercondylar portion 32 can couple the first condylar portion 28 to the second condylar portion 30 and can define an intercondylar recess 37 . The intercondylar recess 37 can rotatably couple the body 22 to the mating portion 12 of the tibial component 10 , and can define an throughbore 35 ( FIG. 2B ) as will be discussed in greater detail below. Further detail regarding the femoral component 8 is outside the scope of the present disclosure but an exemplary femoral component 8 is disclosed in greater detail in commonly assigned United States patent entitled “Floating Bearing Knee Joint Prosthesis With A Fixed Tibial Post,” filed on Dec. 6, 2005, U.S. Pat. No. 6,972,039, which is incorporated by reference herein in its entirety.
[0031] With continuing reference to FIG. 2 , and with additional reference to FIGS. 1-3 , the mating portion 12 can include a bearing member 38 and a tray 40 . The bearing member 38 can include a first bearing surface 42 and a second bearing surface 44 . The first bearing surface 42 can generally include a first bearing portion 46 , a second bearing portion 48 and an intermediate portion 50 to enable the femoral component 8 to articulate with the bearing member 38 . Generally, the first bearing portion 46 can be configured to engage and articulate with the first femoral bearing surface 34 of the first condylar portion 28 and second bearing portion 48 can be configured to engage and articulate with the second femoral bearing surface 36 of the second condylar portion 30 , as is generally known and discussed in greater detail herein.
[0032] The intermediate portion 50 can be positioned between the first bearing portion 46 and the second bearing portion 48 . The intermediate portion 50 can interface with the intercondylar recess 37 of the femoral component 8 . The intermediate portion 50 can comprise a guide post 52 , as in the case of posterior stabilized knee prosthesis ( FIG. 2 ), or can be a slightly raised protrusion 52 a , as in the case of a cruciate retaining knee prosthesis ( FIG. 2A ). Alternatively, the intermediate portion 50 can comprise a guide post 52 b with a throughbore 54 for receipt of a pin 55 ( FIG. 2B ) to couple the bearing portion 38 to the femoral component 8 , through the throughbore 35 as in the case of a hinged knee prosthesis.
[0033] The bearing member 38 can be formed of any suitable material, such as a surgical grade, low friction, low wearing polymeric material, for example, ultra-high molecular weight polyethylene (UHMWPE). Further detail regarding the bearing member 38 is outside the scope of the present disclosure but an exemplary bearing member 38 is disclosed in greater detail in commonly assigned United States patent entitled “Floating Bearing Knee Joint Prosthesis With A Fixed Tibial Post,” filed on Dec. 6, 2005, U.S. Pat. No. 6,972,039, previously incorporated by reference herein. The second bearing surface 44 of the bearing member 38 can be generally smooth and planar. The second bearing surface 44 can be coupled to, rotatable about the tray 40 , or can slideably engage the tray 40 , as is generally known in the art.
[0034] The tray 40 can include a first surface 56 , a second surface 58 and a mating portion or projection 60 . The tray 40 can be composed of a biocompatible metal or metal alloy, such as cobalt-chromium-molybdenum, titanium, or titanium alloy. The first surface 56 can be configured to mate with the second bearing surface 44 of the bearing member 38 and can be generally planar. The first surface 56 can have a high polish to slideably engage the second bearing surface 44 of the bearing member 38 . It should be understood, however, that the tray 40 could engage the bearing member 38 through any appropriate fashion, and could alternatively be coupled to the bearing member 38 similar to the AGC® Total Knee System™, provided by Biomet, Inc. of Warsaw, Ind. The second surface 58 of the tray 40 can be configured to mate with the adaptor assembly 16 and can also be generally planar. The second surface 58 can be coupled to or can define the mating projection 60 .
[0035] Generally, the mating projection 60 can be integrally formed with the tray 40 , however, the mating projection 60 could be coupled to the tray 40 through any appropriate technique, such as the use of bio-compatible mechanical fasteners and/or adhesive. The mating projection 60 can generally be configured to mate with the adaptor assembly 16 , and can include at least one or a plurality of grooves 62 . The grooves 62 can provide channels for receipt of a bio-compatible adhesive to couple the tray 40 to the adaptor assembly 16 , as will be discussed in greater detail herein. It will be understood that although the mating projection 60 is shown as cylindrical, the mating projection 60 could be any desired shape, such as starred, rectangular, square, oval, or any other polygonal shape, and alternatively, the mating projection 60 could be keyed to mate with the adaptor assembly 16 . Alternatively, it should be noted that the tray 40 could define an aperture (not shown) for receipt of a mechanical fastener, such as a bolt, screw or the like, to couple the tray 40 to the adaptor assembly 16 .
[0036] The adaptor assembly 16 can include an adaptor 64 and a sleeve 66 . The sleeve 66 can be configured to receive the mating projection 60 of the tray 40 to couple the tray 40 to the adaptor assembly 16 , as will be discussed in greater detail herein. The adaptor 64 can include a first portion or surface 68 , sidewalls or a base portion 70 and an apex or second surface 72 . With continuing reference to FIGS. 1-3 , and with additional reference to FIG. 3A , the adaptor 64 can be generally conical in shape and symmetric about a centerline C, however, any suitable shape, such as cylindrical, could be employed. The adaptor 64 can be composed of a porous metal material, but any other suitable bio-compatible material, such as titanium, could be employed. Exemplary porous metal materials and exemplary methods for making porous metal may be found in co-pending applications, U.S. Ser. No. (11/357,929, filed Feb. 17, 2006), entitled “Method and Apparatus for Forming Porous Metal Implants”, and U.S. Ser. Nos. (11/111,123 filed, Apr. 21, 2005; Ser. No. 11/294,692, filed Dec. 5, 2005; and Ser. No. 11/357,868, filed Feb. 17, 2006), each entitled “Method and Apparatus for use of Porous Implants,” all assigned to Biomet Manufacturing Corp. of Warsaw Ind., and incorporated herein by reference in their entirety.
[0037] The first surface 68 of the adaptor 64 can be configured to mate with the second surface 58 of the tray 40 , and can be generally planar. The first surface 68 can define a bore 74 for receipt of the sleeve 66 . It should be noted that although the bore 74 is shown as cylindrical, the bore 74 can have any desired shape, such as starred, rectangular, square, or any other polygonal shape, and alternatively could be keyed to mate with the sleeve 66 . The bore 74 can have a diameter D and a depth T. The bore 74 can have a centerline C 1 which can be concentric to the centerline C of the adaptor 64 . The diameter D of the bore 74 can generally be slightly larger than a diameter D 1 of the sleeve 66 so that the sleeve 66 can be slideably coupled to the bore 74 , as will be discussed in greater detail herein. Generally, the first surface 68 can be integrally formed with the base portion 70 ; however, the first surface 68 and base portion 70 could also be coupled together via bio-compatible mechanical fasteners and/or adhesives.
[0038] The base portion 70 can be configured to mate with a portion of the anatomy, such as the tibia 24 . Generally, the base portion 70 can define a base 76 and tapered sidewalls 78 which can extend from the base 76 for a selected distance X into the tibia 24 . It will be understood that the taper on the sidewalls 78 and the distance X to which the sidewalls 78 extend can be selected based on the particular application, such that a variety of configurations of the sidewalls 78 can be employed with a variety of different tibias 24 . Further, a width W of the base 76 can be varied as necessary to correspond to the particular anatomy. The base 76 can include at least one or a plurality of apertures 80 to couple the augment system 20 to the adaptor 64 , as will be discussed in greater detail herein. The sidewalls 78 can generally taper to the second surface 72 .
[0039] The second surface 72 of the adaptor 64 can be generally planar, and can be configured to mate with a portion of the anatomy, such as the tibia 24 . The second surface 72 can define a bore 82 . It should be noted that although the second surface 72 is shown as forming a platform 84 about the bore 82 , the second surface 72 could alternatively comprise an apex defining just the bore 82 . Generally, a centerline C 2 of the bore 82 can be concentric to the centerline C of the adaptor 64 . The bore 82 can define a tapered surface 86 , which can be configured to couple the stem 18 to the adaptor 64 , through a frictional lock, such as a Morse taper, as will be discussed herein. It should be noted, however, that any suitable technique could be used to couple the stem 18 to the adaptor 64 , such as bio-compatible mechanical fasteners and/or adhesives. In addition, as will be discussed herein, the bore 82 can generally be configured to receive any type of stem 18 employed to couple the adaptor assembly 16 to the portion of the anatomy, such as the tibia 24 .
[0040] The sleeve 66 can be slideably and rotatably received in the bore 74 of the first surface 68 of the adaptor 64 . The sleeve 66 can be coupled to the bore 74 through any appropriate technique, such as a slip fit, taper fit or press fit, so long as the sleeve 66 is positionable within the bore 74 . Generally the sleeve 66 can be cylindrical, and can have a centerline C 3 which can be concentric to the centerline C of the adaptor 64 . It should be noted that although the sleeve 66 is shown as cylindrical, the sleeve 66 could have any desired shape, such as such as oval, starred, rectangular, square, or any other polygonal shape, and alternatively, the sleeve 66 could be keyed to mate with the bore 74 of the adaptor 64 . The sleeve 66 can be composed of a bio-compatible metal or metal alloy, such as titanium, titanium alloy, cobalt-chromium-molybdenum or the like.
[0041] The sleeve 66 can include a first surface 88 and a second surface 90 . The first surface 88 can define an offset coupling axis, which can include a bore 92 . The bore 92 can be cylindrical and can have a centerline C 4 which can be offset from the centerline C of the adaptor 64 . The bore 92 can be configured to receive the mating projection 60 of the tray 40 , to couple the tray 40 to the adaptor assembly 16 . It will be understood that although the bore 92 is shown as cylindrical, the bore 92 could be any desired shape, such as starred, rectangular, square, oval, or any other polygonal shape, and alternatively, could be keyed to mate with the mating projection 60 of the tray 40 .
[0042] The bore 92 can be sized larger than the mating projection 60 to enable the receipt of a bio-compatible adhesive material, such as a bio-compatible cement B. The biocompatible adhesive material can be received into the bore 92 with the mating projection 60 disposed within the bore 92 to affix the tray 40 to the adaptor assembly 16 . Alternatively, the bore 92 could be threaded for receipt of a mechanical fastener, such as a screw or bolt, to couple the tray 40 to the sleeve 66 (not shown). It should also be noted that the sleeve 66 as described herein is optional and the tray 40 could be coupled to an offset coupling axis defined in the bore 74 of the adaptor 64 (not shown). The adaptor assembly 16 can be coupled to the stem 18 and the augment system 20 .
[0043] The stem 18 can include a first end 94 and a second end 96 . The first end 94 of the stem 18 can be coupled to the adaptor assembly 16 and the second end 96 can be coupled to a portion of the anatomy, such as the tibia 24 . The stem 18 can be composed of any suitable bio-compatible material, such as a bio-compatible metal or metal alloy. It should be understood, however, that the stem 18 as described herein, is merely exemplary, as various stems could be employed with the adaptor assembly 16 as is generally known in the art.
[0044] The first end 94 of the stem 18 can generally include a tapered surface 98 configured to engage the tapered surface 86 of the bore 82 of the adaptor 64 to couple the stem 18 to the adaptor 64 . The tapered surface 86 can generally frictionally lock the stem 18 to the adaptor 64 , and can comprise a Morse taper, however any other technique could be used to couple the stem 18 to the adaptor 64 , such as mechanical fasteners and/or adhesives. The first end 94 can be coupled to the second end 96 , and could also be integrally formed with the second end 96 . The second end 96 of the stem 18 could have any suitable configuration as necessary to mate with the anatomy, and further, the second end 96 of the stem 18 can be offset from the first end 94 of the stem 18 if desired (not shown). The second end 96 of the stem 18 can include ribs 99 to facilitate the engagement of the stem 18 with the anatomy. It will be understood, however, that the ribs 99 are optional.
[0045] The augment system 20 can be coupled to the base 76 of the base portion 70 of the adaptor 64 . It should be noted that the augment system 20 , as disclosed herein, can be used with any suitable knee implant assembly and further the knee implant assembly 6 can be implemented without the augment system 20 if desired. Generally, the augment system 20 can include at least one or a plurality of augments 100 which can be mechanically fastened to at least a portion of the sidewalls or base portion 70 of the adaptor 64 via at least one or a plurality of bio-compatible fasteners 102 . It should be understood, however, that the augment 100 could be coupled to the base portion 70 of the adaptor 64 through any other suitable technique, such as the use of a bio-compatible adhesive or the like.
[0046] The augment 100 can be composed of a suitable bio-compatible material, such as a metal or metal alloy, and can be composed of a porous metal material, previously incorporated by reference herein. The augment 100 can be any shape required for the particular portion of the anatomy, such as semi-circular, rectangular or the like. If a fastener 102 is employed to couple the augment 100 to the anatomy, then the augment 100 can define at least one throughbore 104 for receipt of the fastener 102 .
[0047] With additional reference now to FIG. 4 , in order to couple the knee implant assembly 6 to the anatomy, the tibia 24 and femur 26 (not shown) can be resected and prepared as is generally known in the art. Then, the femoral component 8 can be coupled to the femur 26 , as is generally known in the art. Then, the adaptor 64 can be coupled to the stem 18 and then the stem 18 can be press-fitted into a first bore 110 formed in the tibia 24 . With additional reference to FIG. 5 , if the augment system 20 is employed, the augment system 20 can be coupled to the adaptor 64 prior to the adaptor 64 being coupled to the stem 18 .
[0048] In order to couple the augment 100 to the adaptor 64 , the base 76 of the adaptor 64 can be drilled (not shown) to form the aperture 80 . Then, the fastener 102 can be inserted through the throughbore 104 of the augment 100 and into the aperture 80 of the adaptor 64 to couple the augment 100 to the adaptor 64 . After the desired number of augments 100 are coupled to the base 76 of the adaptor 64 , the sleeve 66 with the most appropriate offset can be selected and the sleeve 66 can then be coupled to the adaptor 64 . With additional reference to FIG. 6 , the adaptor assembly 16 can then be coupled to the stem 18 , such that the tapered surface 86 of the bore 82 of the adaptor 64 can engage the tapered surface 98 of the first end 94 of the stem 18 to couple the stem 18 to the adaptor 64 .
[0049] After the adaptor assembly 16 is coupled to the stem 18 , the stem 18 and adaptor assembly 16 can be inserted into the tibia 24 , with the stem 18 being inserted into the first bore 110 such that the adaptor assembly 16 engages the second bore 112 . Then, the mating portion 12 can be coupled to the adaptor assembly 16 , as shown in FIG. 7 . Generally, the bearing member 38 can be coupled to the first surface 56 of the tray 40 before the tray 40 is coupled to the adaptor assembly 16 (not specifically shown). Then, once the bearing member 38 is coupled to the tray 40 , the sleeve 66 can be rotated as necessary within the adaptor 64 to properly align the tray 40 , or to provide the best coverage of the tibia 24 .
[0050] Once the offset bore 92 of the sleeve 66 is properly aligned, the bio-compatible cement B can be inserted into the bore 92 of the sleeve 66 . Then, the mating projection 60 of the tray 40 can be inserted into the offset bore 92 of the sleeve 66 . The insertion of the mating projection 60 into the offset bore 92 can cause the cement to flow around the grooves 62 of the mating projection 60 to assist in securing the tray 40 to the adaptor assembly 16 (as best shown in FIG. 2 ). Once the tray 40 is coupled to the adaptor assembly 16 , the intercondylar recess 37 of the femoral component 8 can be mated with or coupled to the intermediate portion 50 of the bearing member 38 such that the first femoral bearing surface 34 and second femoral bearing surface 36 of the femoral component 8 are aligned with the first bearing portion 46 and the second bearing portion 48 of the bearing member 38 .
[0051] With reference now to FIGS. 8 , 8 A and 9 , an alternative knee implant assembly 6 a is shown. The alternative knee implant assembly 6 a can include a femoral component 8 a and a tibial component 10 a . In the alternative knee implant assembly 6 a , the adaptor assembly 16 , stem 18 and augment system 20 can be coupled to the distal end of the femur 26 to form the femoral component 8 a . The tibial component 10 a can include an articulating or mating portion 12 a to enable the femoral component 8 a to articulate with respect to the tibial component 10 a.
[0052] With continuing reference to FIG. 8 , the femoral component 8 a can include an articulating portion or body 22 a , the adaptor assembly 16 , the stem 18 and the augment system 20 . As the adaptor assembly 16 , stem 18 and augment system 20 are substantially similar to the adaptor assembly 16 , stem 18 and augment system 20 described in conjunction with FIGS. 1-7 , they will not be described in detail with regard to the femoral component 8 a . It should be noted, however, that the augment system 20 of the femoral component 8 a can generally include at least two augments 100 , with at least one augment 100 per condylar surface 200 of the femur 26 (as best shown in FIG. 11 ).
[0053] With continued reference to FIGS. 8-10A , the body 22 a of the femoral component 8 a can include a post 202 coupled a surface 204 of the intercondylar portion 32 to couple the body 22 a to the adaptor assembly 16 . The post 202 can be configured to couple the femoral component 8 a to the adaptor assembly 16 . Generally, the post 202 can be sized to be received into the offset coupling axis or offset bore 92 of the sleeve 66 . It will be understood that although the post 202 is shown as cylindrical, the post 202 can have any desired shape such as starred, oval, rectangular, square, or any other polygonal shape, and alternatively could be keyed to mate with the offset bore 92 of the sleeve 66 .
[0054] The post 202 can include at least one or a plurality of grooves 206 to assist in coupling the post 202 , and thus the body 22 a , to the sleeve 66 of the adaptor assembly 16 . The post 202 can be coupled to the bore 92 of the sleeve 66 through the use of a bio-compatible adhesive, such as the bio-compatible cement B. Alternatively, the body 22 a could be coupled to the sleeve 66 via a bio-compatible mechanical fastener, such as a bolt or a screw, which could extend through a throughbore (not shown) in the body 22 a to threadably engage threads (not shown) formed in the bore 92 of the sleeve 66 .
[0055] The tibial component 10 a , and the mating portion 12 a of the alternative knee implant assembly 6 a , can be any generally known suitable tibial component 10 a and mating portion 12 a , like the tibial component of the AGC® Total Knee System™, or the AGC® Tradition High-Post Knee System™, or the Orthopaedic Salvage System™, all provided by Biomet, Inc. of Warsaw, Ind. Alternatively, the tibial component 10 a could be the tibial component 10 as described with reference to FIGS. 1-7 .
[0056] With additional reference to FIG. 11 , in order to couple the alternative knee implant assembly 6 a to the anatomy, the tibia 24 and femur 26 (not shown) can be resected and prepared as is generally known in the art. In order to couple the femoral component 8 a to the femur 26 , the adaptor 64 can be coupled to the stem 18 and then the stem 18 can be press-fit into a first bore and a second bore formed in the femur 26 (not specifically shown). If the augment system 20 is employed, prior to insertion into the anatomy, the augments 100 and the most appropriate sleeve 66 can be coupled to the adaptor assembly 16 , as discussed previously herein. Then, the sleeve 66 can be rotated until the offset bore 92 is in the desired orientation for mating the femoral component 8 a with the tibial component 10 a.
[0057] Once the sleeve 66 is properly aligned, the bio-compatible cement B can be placed into the offset bore 92 and then the post 202 of the body 22 a can be inserted into the offset bore 92 to couple the body 22 a to the adaptor assembly 16 . After the body 22 a is coupled to the adaptor assembly 16 , the adaptor assembly 16 can be coupled to the stem 18 , and then the stem 18 and adaptor assembly 16 can be inserted into the first bore and the second bore formed in the femur 26 (not specifically shown). Generally, when the adaptor 64 is coupled to the stem 18 , the body 22 a becomes properly engaged with the femur 26 , and the tibial component 10 a can then be coupled to the tibia 24 , as is generally known in the art.
[0058] The description of the teachings herein is merely exemplary in nature and, thus, variations that do not depart from the gist of the teachings are intended to be within the scope of the teachings. Such variations are not to be regarded as a departure from the spirit and scope of the teachings. | A prosthesis for replacing an articulating portion of bone is provided. The prosthesis can include an adaptor operable to replace a portion of the bone. The prosthesis can further include a sleeve coupled to the adaptor. The sleeve can define an offset coupling axis. The prosthesis can also include an articulating portion operable to replace the articulating portion of the bone. The sleeve can be positionable to couple the articulating portion to the offset coupling axis at a predetermined orientation. | 0 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates to the field of dynamic caching and, more particularly, to exposing internal dynamic caching services of a Web-based application server to remote components.
[0003] 2. Description of the Related Art
[0004] Caching is a technique of temporarily storing frequently accessed data in random access memory (RAM) or in a special area of a hard disk drive, to reduce the time required to read and write data. Server-side caching techniques are often used to improve performance of Web applications. Conventional solutions for caching static content have resulted in excellent performance gains for many Web applications. Unfortunately, these caching solutions are of little to no value in enhancing the performance of Web applications with dynamically generated content. For dynamic content caching to be effective, dynamic content or data, which is by definition subject to change, must be stable over a long enough time for meaningful reuse to occur. If access is frequent, even a short period of stability can provide a significant enough performance increase to warrant data caching.
[0005] International Business Machine (IBM), Corporation of Armonk, N.Y. has developed and refined technologies that enable the caching of dynamic content. The technology has been included in a dynamic content caching solution for Java 2 Enterprise Edition (J2EE) applications running on WebSphere-type Application Server™ (WAS) version 5.0 and higher, where the built in dynamic caching server can be referred to as a dynacache, where a WebSphere-type Application server can include a WebSphere application server in any version or configuration as well as servers derived from or based upon the WebSphere architecture. The dynacache operates within a WAS Java Virtual Machine (JVM) to provide generalized Java object caching for use by various internal components. The dynacache can cache objects directly in WAS memory spaces with the ability to “overflow” objects to disk to avoid over-utilizing RAM. The dynacache memory can be distributed across multiple servers and managed as a single logical memory space. The dynacache can be optionally replicated across a cluster to avoid expensive regeneration on each server when multiple servers are used. As a service, the dynacache can be configured, tuned, and monitored through system management interfaces of the WAS.
[0006] In a simplified form, the dynacache can be conceptualized as a robust Hashtable capable of storing and retrieving Java objects from memory. The dynacache can manage entries by controlling growth using replacement and/or eviction algorithms. Entries within the cache can be managed by a policy based on the class of entry, such as servlet, Java Server Page (JSP), Enterprise Java Bean (EJB), command, and the like. The policy can be expressed in an electronic document, such as an Extensible Markup Language (XML) file (cachespec.xml).
[0007] The dynacache uses a facility called the Data Replication Service (DRS), which is a Java Messaging Service (JMS) based facility, to replicate cached data and propagate invalidate events within a WebSphere cluster. Invalidate events are events that remove an object from a cache and/or mark an object within the cache for removal. Additionally, to support caching performed outside of the J2EE application space, the dynacache can cooperate with a plurality of caches within the WAS through one or more cache adapters to actively trigger invalidations of cached Web content to registered adapters. Registered adaptors include the WebSphere HTTP (Hypertext Transfer Protocol) Plugin, IBM HTTP Server, the Fast Response Cache Accelerator (FRCA) cache, and the WebSphere Edge Server. Accordingly, some level of data sharing and synchronization can be performed between the dynacache and other caches and/or application servers.
[0008] There is currently no way, however, for components that do not run inside the WAS to directly access objects within the dynacache and data embedded within these objects. Objects within the dynacache are typically Java objects that include internal data and private methods for accessing the internal data.
[0009] By way of example, the dynacache can contain compiled speech grammars and a Java Grammar Compiler running inside an EJB can place grammars in the dynacache. An external software component can receive compiled grammar files from the WAS, where the files are generated from information within the dynacache. Even so, the external software component cannot directly access objects within the dynacache to obtain and/or manipulate the speech grammar information contained within the dynacache. This is true regardless of whether the external software component is a J2EE component external to the WAS or a component written in a non-Java language, such as a component written in the “C” programming language.
SUMMARY OF THE INVENTION
[0010] The present invention creates an interface to a dynamic cache that is internal to an application server. The interface can expose dynamic cache services to components external to the application server. For example, in one embodiment, the solution provided herein describes an interface to the dynacache of a WebSphere-type Application Server (WAS) that can be used by components outside the WAS.
[0011] More specifically, the solution can create an externally accessible interface to expose the dynacache's DistributedMap Application Program Interface (API), which is normally a local interface. In a particular embodiment, a Java HTTP servlet can expose the DistributedMap API to permit components written in any programming language to access the dynacache via an HTTP interface. In another embodiment, a stateless session EJB can extend and expose the dynacache API providing dynacache access to Java 2 Enterprise Edition (J2EE) components that are external to the WAS.
[0012] One aspect of the present invention can include a method for accessing an internal dynamic cache of a WAS from an external component. The method can include the step of establishing a software interface component within the WAS. The software interface component can receive a request from the external component. The request can include an identifier for a cache object and at least one dictate concerning the cache object. The external cache component can lack privileges to directly execute programmatic actions upon the cache object. The software interface component can trigger a programmatic action in accordance with the dictate. The programmatic action can involve the cache object, wherein the programmatic action utilizes the internal dynamic cache and involves the cache object. The programmatic action can be an action performed local to the WAS.
[0013] Another aspect of the present invention can include a dynamic caching system that includes a Web-based application server, a remote component, and a software interface object. The Web-based application server can include a dynamic cache into which software objects are placed. The dynamic cache can be a single logical memory space that includes a multitude of physical memory spaces distributed across multiple computing devices. For example, the Web-based application server can be a WAS and the dynamic cache can be a dynacache. The remote component can be a software component external to the Web-based application server that lacks privileges to directly perform actions upon objects within the dynamic cache. The software interface object can be internal to the Web-based application server. The software interface object can receive a request from the remote component and can responsively trigger a programmatic action against an identified software object in the dynamic cache in accordance with the request.
[0014] Moreover, this invention can be implemented as a program for controlling a computer to implement the functions described above, or a program for enabling a computer to perform the process corresponding to each step of the method presented above. This program may be provided by storing the program in a magnetic disk, an optical disk, a semiconductor memory, any other recording medium, or distributed via a network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] There are shown in the drawings, embodiments that are presently preferred; it being understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
[0016] FIG. 1 is a schematic diagram illustrating a system that includes a software interface object exposing a dynamic cache of a Web-based application server in accordance with the inventive arrangements disclosed herein.
[0017] FIG. 2 is a flow chart illustrating a method for accessing a dynamic cache internal to a Web-based application sever from an external component in accordance with the inventive arrangements disclosed herein.
[0018] FIG. 3 is expository pseudo-code for a software interface object in accordance with the inventive arrangements disclosed herein.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The subject matter presented herein discloses a software interface object that can permit software components external to a Web-based application server to access a dynamic cache of the Web-based application server even though access to the dynamic cache is typically limited to internal components. In one embodiment, the Web-based application server can be a Websphere-type Application Server (WAS) and the dynamic cache can be a dynacache of the WAS.
[0020] FIG. 1 is a schematic diagram illustrating a system 100 that illustrates the placement of a software interface object relative to a Web-based application server and a remotely located software component in accordance with the inventive arrangements disclosed herein. The system 100 can include an application server 150 communicatively linked to a remote server 140 through an external component 110 that is linked to software interface object G and/or software interface object H. Software interface objects G and H can expose at least one dynamic cache service to the external component 110 . It should be appreciated that the dynamic cache can be distributed across multiple locations within the application server 150 . Accordingly, the dynamic cache can include local cache 176 , local cache 186 , as well as other localized caches disposed throughout the application sever 150 . Particular ones of these local caches can be associated with software interface objects to expose either the local cache objects and/or the dynamic cache to the external component 110 . For example, cache 176 can be associated with software interface object G and cache 186 can be associated with software interface object H.
[0021] It should be noted that the software interface objects G and/or H can be disposed within virtual machines included in the application server 150 , such as dialogue server 170 and/or speech server 180 . The invention is not limited in this regard, however, and the software interface objects G and H can be placed anywhere within the application server 150 that permits access to the internal dynamic cache of the application server 150 .
[0022] The application server 150 can function as a transaction engine that operates as a reliable foundation for handling high volume secure transactions and Web services. In one embodiment, the application server 150 can be a Websphere Application Server (WAS).
[0023] In one arrangement, the application server 150 can include a multitude of component servers, such as telephone server 160 , dialogue server 170 , and speech server 180 , communicatively linked via a multitude of Web servers 152 . Each Web server 152 can include one or more plug-ins 154 , where each plug-in 154 can include routines for conveying data to particular component servers within the application server 150 . In a particular arrangement, component servers of the application server 150 can also be distributed across a network. In such an arrangement, data can be conveyed to each of the component servers via the Web servers 152 . The Web servers 152 can utilize Hypertext Protocol Format (HTTP) for compatibility with IP sprayers and firewalls.
[0024] The telephone server 160 , the dialogue server 170 , and the speech server 180 can be implemented as virtual machines, such as virtual machines complying with the J2EE specification. The telephone server 160 can control the setup, monitoring, and tear down of phone calls. In one arrangement, telephone server 160 can include a web container 160 and an EJB container 164 . Moreover, the telephone server 160 can include a call control servlet (servlet A), a call control EJB (Bean B), and a call control interpreter EJB (Bean C).
[0025] The dialogue server 170 can manage tasks relating to call dialogue for the application server 150 . In one arrangement, the dialogue server 170 can include web container 172 and EJB container 174 . Moreover, the dialogue server 170 can include a voice markup interpreter EJB (Bean D).
[0026] The speech server 180 can handle one or more speech services for the application server 150 . In one arrangement, the speech server 180 can include web container 182 and EJB container 184 . Moreover, the speech server 180 can include automatic speech recognition (ASR) EJB (Bean E) as well as a text-to-speech EJB (Bean F). It should be appreciated that the application server 150 can be arranged in a multitude of fashions and that the invention is not to be limited to the illustrative arrangement presented herein.
[0027] FIG. 2 is a flow chart illustrating a method 200 for accessing a dynamic cache internal to a Web-based application server from an external component in accordance with the inventive arrangements disclosed herein. The Web-based application server can be a WAS and the dynamic cache can be a dynacache of the WAS. The method can begin in step 205 , where a software interface component can be established within a WAS. In step 210 , a request from a component external to the WAS can be received by the software interface component. For example, the request can be conveyed via HTTP through a Web-based communication link between the server upon which the external component is located and the WAS server in which the software interface component is disposed. In step 215 , the software interface component can identify an object within the dynacache and a dictate from information contained within the request.
[0028] In step 220 , the software interface object can locally trigger a programmatic action in accordance with the dictate. Programmatic actions include actions that get or retrieve data from a cache object, put data into a cache object, and/or remove cache objects from the dynacache. Data inserted into the cache objects can be specified by parameters contained within the request. Further, options can be associated with the programmatic actions that can be detailed within the request. For example, an invalidation action, that removes a cache object from the data cache, can specify whether removal is to occur immediately or responsive to a the occurrence of a defined event.
[0029] In one embodiment, the software interface object can access a method of an application program interface (API) associated with the dynacache, such as a Distributed Map API. In such an embodiment, the API method can perform the programmatic action responsive to a trigger from the software interface component.
[0030] In step 225 , a result can be received responsive to the triggered action. Not all programmatic actions need return results. In step 230 , the results can be incorporated into a response parameter and conveyed to the external component.
[0031] The present invention can be realized in hardware, software, or a combination of hardware and software. The present invention can be realized in a centralized fashion in one computer system or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system or other apparatus adapted for carrying out the methods described herein is suited. A typical combination of hardware and software can be a general-purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein.
[0032] FIG. 3 is expository pseudo-code for a software interface object in accordance with the inventive arrangements disclosed herein. The software interface object can accept dictates for performing actions involving the dynamic cache from an external component. Objects within the dynamic cache upon which actions can be performed can include Java 2 Enterprise Edition (J2EE) components. Actions performed against these J2EE components can include get data actions, put data actions, and invalidate object actions, where an invalidate object action can remove an identified J2EE component from the dynamic cache. The software interface object, being internal to the application server, is able to expose internal capabilities of the dynamic cache to the external component. In one embodiment, the software interface object can utilize an application program interface (API) of the dynamic cache. For example, when the application server is the WAS, the API can be the DistributedMap API.
[0033] In one embodiment, the software interface object can be implemented as a public stateless session Enterprise Java Bean (EJB) executing within a virtual machine of the application server. It should be noted that such an implementation can expose dynamic cache services to external Java components.
[0034] A more generic implementation of the software interface object can place a servlet within the Web-based application server. The servlet can accept requests from external components and can return responsive parameters using a Hypertext Transfer Protocol (HTTP). An HTTP servlet implementation can expose dynamic cache services to external components written in any programming language.
[0035] It should be appreciated that the presented coding example in FIG. 3 provides just one illustrative method of implementing a software interface object and that the invention is not to be limited in this regard. For example, an otherwise private Java class with access to dynamic cache objects can be extended by a public class, where instantiations of this public class can be a software interface object as defined herein.
[0036] The present invention also can be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which when loaded in a computer system is able to carry out these methods. Computer program in the present context means any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following: a) conversion to another language, code or notation; b) reproduction in a different material form.
[0037] This invention can be embodied in other forms without departing from the spirit or essential attributes thereof. Accordingly, reference should be made to the following claims, rather than to the foregoing specification, as indicating the scope of the invention. | A method for accessing an internal dynamic cache of a Websphere-type Application Server (WAS) from an external component that includes the step of establishing a software interface component within the WAS. The software interface component can receive a request from the external component. The request can include an identifier for a cache object and at least one dictate concerning the cache object. The external cache component can lack privileges to directly execute programmatic actions upon the cache object. The software interface component can trigger a programmatic action in accordance with the dictate. The programmatic action can involve the cache object, wherein the programmatic action utilizes the internal dynamic cache and involves the cache object. The programmatic action can be an action performed local to the WAS. | 8 |
FIELD OF THE INVENTION
The present invention relates to a method for producing an emulsion and an apparatus therefor, and more particularly to a method of producing an oil-in-water type emulsion in which the oil globules are prevented from growing coarse and an apparatus used therefor.
BACKGROUND OF THE INVENTION
The oil-in-water type emulsion technology is widely used in producing photographic light-sensitive materials, cosmetics, foods, paints and chemicals.
For example, in the field of photographic light-sensitive materials, color image-forming compounds such as color couplers, diffusion transfer compounds, antistain agents, anti-discoloration agents, anti-color-mixing agents, ultraviolet absorbing agents, color-increasing agents and the like are used as oil-soluble substances for making their emulsions. The preparation of oil-in-water type emulsions of such oil-soluble substances has conventionally been made in the manner that an oil phase solution prepared by dissolving the oil-soluble substance in an organic solvent or emulsification aid or in an organic solvent solution of an emulsification aid or, where the oil-soluble substance is solid, by heating or dissolving it in an organic solvent (hereinafter merely called an oil phase solution) is added to be emulsified/dispersed in a water-soluble binder-containing and as needed an emulsification aid-added water phase solution (hereinafter merely called a water phase solution) to thereby produce an oil-in-water type emulsion having an average oil globular size of about 0.1 to 1.0 μm.
As the above organic solvent, in many cases, a low-boiling solvent having a lower boiling point than that of water, such as ethyl acetate, is used.
A conventional procedure for the above emulsion preparation is such that the water phase solution is put in a stirrer-provided emulsification tank, and onto the surface of the solution, with stirring, is added the oil phase solution.
In addition, there are other procedures: addition by conduction of the oil phase into the water phase solution as disclosed in Japanese Patent Publication Open to Public Inspection (hereinafter abbrebiated to JP O.P.I.) No. 203632/1984; and conduction of the water phase into the oil phase solution to the contrary. These procedures, however, have difficulty in securely adding all the amount of one phase solution to the other because, when forcibly conducting the adding phase by, e.g., a pump, there is a possibility of undesirable air-mixing at the end of the conduction, in which the air-mixing occurrence causes a large amount of foam, giving additional troubles to work.
Therefore, the foregoing addition of the oil phase onto the surface of the water phase solution is generally used. In this instance, however, the oil phase solution is splashed up onto the inside wall of the emulsification tank, the oil phase substance, after the emulsification, is dripped from the wall to be mixed in the dispersion, resulting in coarse oil globules of the undispersed oil phase substance which, when the dispersion is used in, e.g., a light-sensitive material, may sometimes cause coating trouble such as pinholes.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a means of preventing coarse oil globules from occurring in a method for producing an emulsion and an apparatus used therefor.
It is another object of the invention to provide a method for preventing coating trouble attributable to the formation of coarse oil globules and an apparatus used therefor.
The above objects are accomplished by a method for producing an emulsion by a stirrer/disperser, in which said method comprises a predispersion procedure for dispersing a water phase solution and an oil phase dispersion beforehand, and by an apparatus used for said method.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a cross-sectional view of an example of the emulsifier/disperser of the invention.
FIG. 2 is a graph showing the numbers of globules in various globular sizes of the emulsions in both Examples and Comparative examples.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a cross-sectional view of an example of the emulsifier/disperser of the invention, in which the respective solutions prepared in a water phase solution preparation tank 1 and an oil phase solution preparation tank 2 are transported by a pump P controlled by a force-feed-system to an in-line mixer 3 for premixing, and then sent to an emulsification tank 4 for emulsification/dispersion.
The above preparation tanks 1 and 2 are ordinary solution-preparation tanks provided with jackets. The premixer 3 may be any one of various in-line mixers, such as a Static Mixer, manufactured by Noritake Co., Ltd., T.K. Homomix Line Flow, manufactured by Tokushu Kikako Co., and Ebara Milder, manufactured by Ebara Mfg. Co., Ltd.
As the emulsification tank 4, any emulsifier/disperser having an ordinary stirrer may be used without restriction.
The flow rate of the oil phase solution divided by that of the water phase solution preferably is not more than 1.2 and not less than 0.1 and more preferably is not more than 1.0 and not less than 0.3.
By doing the predispersion described above the formation of coarse oil globules can be prevented to cause no splattering of oil globules onto the inside wall of the emulsification tank, thus enabling to prevent pinhole trouble at the time of coating a light-sensitive material.
EXAMPLES
The invention is further illustrated in detail by the following examples.
EXAMPLE 1
______________________________________Water phase solution10% Sodium dodecylbenzenesulfonate 1400 mlPhotographic gelatin 3.0 kgWater 27000 mlOil phase solution1-(2,4,6-trichlorophenyl)-3-[3-(2,4-di-t- 3.0 kgaminophenoxyacetamido)benzamido]-5-pyrazoloneTricresyl phosphate 3.0 kgEthyl acetate 6000 ml______________________________________
The apparatus shown in FIG. 1 was used. As a premixer a T.K. Homomix Line Flow was used. The water phase solution and the oil phase solution were supplied at flow rates of 14 liters per minute and 6 liters per minute, respectively, from the respective solution preparation tanks to the premixer.
The mixed liquid was put in a 50-liter emulsification tank, and after that, the liquid was emulsified/dispersed for 50 minutes by a 150 mmφ dissolver at 4000 rpm.
The average oil globule size and globule size distribution of the obtained emulsion were examined. Next, the emulsion was coated on a polyethylene terephthalate film by a slide hopper-type coater, and then 10 sheets of 1 m×30 cm size coated samples were prepared therefrom. The number of coarse oil globules having not smaller than 10 μm that appeared in the coated area was examined.
EXAMPLE 2
The water phase solution of Example 1 alone was first flow for one minute at a flow rate of 2 liters per minute and then at a flow rate of 12 liters per minute, together with the oil phase solution for 2 minutes at a flow rate of 6 liters per minute for predispersion, and finally the remaining water phase solution was flowed to the emulsification tank. After that, the emulsification/dispersion of the liquid was carried out in the same manner as in Example 1.
COMPARATIVE EXAMPLE 1
The emulsification/dispersion was performed in the same manner as in Example 1 except that, without using the premixer, the oil phase solution was first put in an emulsification tank, and then onto the oil phase solution was added the water phase solution.
The results of the above examples are as follows:
______________________________________ Average Number of coarse globule size oil globules______________________________________Example 1 0.21 μm 2Example 2 0.20 μm 0Comparative example 1 0.24 μm 16______________________________________
The oil globule size distributions of the above examples are shown in FIG. 2.
The average globule size was determined by Coulter model N-4 and the number of coarse oil globules by Coultisizer.
As is apparent from the above results, the examples which use the method and apparatus of the invention show smaller average globule sizes and smaller number of coarse oil globules than those of the comparative example. In addition, the method of Example 2 shows more excellent results than those of Example 1.
Thus, the present invention provides a method and an apparatus useful for preventing the formation of coarse oil globules in the manufacture of emulsions, which results in prevention of the coating trouble attributable to the coarse oil globules. | A process of making emulsion for photographic material being prevented from coarse oil globules mixed-in which causes visible spots on the final products is disclosed. Before mixing and emulsifying oil phase and water phase in an emulsifying tank, said two phases are pre-mixed air-tightly in an in-line-mixer to minimize the above mentioned trouble. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
The present application claims priority to U.S. Provisional Application Ser. No. 60/347,667 filed on Jan. 10, 2002.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to pet carriers and, more specifically, to a compressible pet carrier adapted for comfortable carriage by a pet owner.
2. Description of Prior Art
Pet owners have traditionally relied on rigid cages to contain pets while traveling. These cages are often bulky and difficult to move and they are not suitable for modern traveling conditions where limited space is available or for an active lifestyle, such as when jogging or rollerblading. Generally, these unwieldy carriers cannot be used if the pet owner is traveling by foot because they are too cumbersome to carry by hand and may have to be wheeled or placed on a trolley.
Lighter weight carriers made from flexible materials that are designed to be carried like a purse or shoulder bag have been designed for use by pet owners traveling on foot. These carriers, however, lack proper ventilation, do not allow access for water, are difficult to access, lack safety measures, and are not adaptable for safe and comfortable when traveling in a vehicle, such as an automobile or airplane. These carriers are also prone to becoming unbalanced because of the motion of the pet or the way the carrier must be transported. As these carriers must be held in one hand or worn over a single shoulder and pets can be quite heavy, carriage for any appreciable
Lighter weight carriers made from flexible materials that are designed to be carried like a purse or shoulder bag have been designed for use by pet owners traveling on foot. These carriers, however, lack proper ventilation, do not allow access for water, are difficult to access, lack safety measures, and are not adaptable for safety and comfort when traveling in a vehicle, such as an automobile or airplane. These carriers are also prone to becoming unbalanced because of the motion of the pet or the way the carrier must be transported. In addition, the lack of a proper support structure can distort the interior room of the carrier, causing discomfort to the pet. As these carriers must be held in one hand or worn over a single shoulder and pets can be quite heavy, carriage for any appreciable distance often becomes tiring and the owner has to frequently shift the way that the carrier is held.
While pet carriers have been designed for use in cars or on airplanes, these carriers are typically very rigid and cannot fit into non-geometric spaces, such as under an airplane seat. As a result, the pet may often have to travel in the luggage compartment where conditions are often unsafe for animals. Those carriers that are designed from flexible materials are without any structural support to prevent collapse onto an enclosed pet and result in reduced interior space for the pet, a severe detriment during long transit periods.
3. Objects and Advantages
It is a principal object and advantage of the present invention to provide a pet carrier that is convenient to use and can be comfortably worn by a pet owner.
It is an additional object and advantage of the present invention to provide a pet carrier that has a flexible structure that can be compressed during use and collapsed for storage.
It is a further object and advantage of the present invention to provide a pet carrier that is safe for use when traveling in a vehicle.
It is another object and advantage of the present invention to provide a pet carrier that allows a pet to have adequate access to air and water.
Other objects and advantages of the present invention will in part be obvious, and in part appear hereinafter.
SUMMARY OF THE INVENTION
In accordance with the foregoing objects and advantages, the present invention provides a flexible pet carrier having a support structure, a leveling system and climate control compartment that is convenient to use and can be comfortably worn by a pet owner. The pet carrier comprises a flexible enclosure formed from a series of interconnected panels supported by removable stiffening members. A transverse beam stiffener extends longitudinally along the roof panel and cooperates with a pair of transverse support members removably attached to either end of the enclosure. The support members are preferably semi-rigid plastic pieces that are flat or planar and can be flexed by the application of force. A user inserts the transverse support members by bending them into an arch, inserting into the enclosure, and engaging them into place via a series of fasteners. The support members then flex outwardly to assist in supporting the roof of the enclosure. As the support members are semi-rigid, the roof of the enclosure may be resiliently deformed as needed, such as for placing the carrier under a passenger airline seat. Further flexibility is achieved by disengaging one or more of the fasteners, thereby reducing the height of the enclosure without fully collapsing the unit. Removal of the support members allows a user to collapse the pet carrier to a substantially flat configuration.
The pet carrier of the present invention further comprises a detachable shoulder strap system for carrying the pet carrier like a backpack and a leveler for balancing the carrier when worn by the user. The leveler includes a pair of front extension straps having two ends, wherein each front extension strap is attached at one end to a respective end of the shoulder straps. Each of the front extension straps extends over the roof of the enclosure and the other end of the strap is removably attached to the front side of the enclosure. An adjusting mechanism is provided on each front extension strap for adjusting the length of the strap to level the floor of the enclosure when carried by the user.
The pet carrier of the present invention also comprises an air conditioning compartment attached to the inside portion of the roof of the enclosure. At least a portion of the air conditioning compartment is located in the interior of the enclosure, and at least one opening, such as a mesh panel, allows air to flow between the compartment and the interior of said enclosure. Preferably, access doors to the compartment are also provided within the roof of the enclosure and on one side of the compartment. The compartment can optionally hold a means for conditioning the air within said enclosure, such as a heating or cooling pad, an odor remover, or an air freshener.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front perspective view of a pet carrier according to the present invention.
FIG. 2 is a rear perspective view of a pet carrier according to the present invention.
FIG. 3 is a plan view of the shoulder strap system of the present invention.
FIG. 4 is a perspective view of an accessory item for use with shoulder strap system of the present invention.
FIG. 5 is an exploded view of a bottom panel of the pet carrier of the present invention.
FIG. 6 is a rear perspective view of the pet carrier of the present invention.
FIG. 7 is a side perspective view of a pet carrier and the shoulder strap system according to the present invention.
DETAILED DESCRIPTION
Referring now to the drawings in which like numerals refer to like parts throughout, there is seen in FIG. 1 a pet carrier 10 according to the present invention generally comprising an enclosure 12 formed from a series of flexible panels preferably formed from a waterproof or water resilient fabric. Panels include a floor panel 14 , two side panels 16 and 18 attached along their lower edges to floor 14 , and an arcuate top panel 20 fixedly attached along either end to floor panel 14 and releaseably attached along its lateral edges to side panels 16 and 18 . Panels may be interconnected via stitching or other means for fixedly attaching fabric panels together and it should be recognized by one of skill in the art that any number of individual panels may be interconnected together in to form the various elements of enclosure 12 . Panels are preferably formed from two- or three-ply material containing a soft padding and have a water-resistant coating. Panels may also contain semi-rigid plastic sheets between the plies in areas that need additional reinforcement.
Side panels 16 and 18 are releasably attached to top panel 20 and fixedly attached to floor panel 14 , such as by a double-headed zipper provided that zipper does not allow zipper heads to slide backward when force is applied from inside enclosure 12 by a pet. In order to prevent leaks of pet droppings and meet aviation transportation requirements for cargo shipping (no such requirements are known for travel in the cabin area), the releasable portion of both side panels 16 and 18 should begin at least one inch above seam with floor panel 14 .
Side panels 16 and 18 preferably contain netted windows 22 in their upper portion, thereby enabling ventilation and visibility into and out of enclosure 12 . Side panels 16 and 18 preferably contain at least one-half solid material to provide sufficient strength. Additional webbing 24 may be sewn along the middle of windows 22 in side panels 16 and 18 to improve structural integrity. The seams between side panels 16 and 18 and floor panel 14 or top panel 20 may additionally contain piping 26 with plastic wire for reinforcement.
As seen in FIG. 6 , the structural integrity of carrier 10 is maintained by a system of resilient members that engage the material forming the outer surface of carrier 10 . Two arches 28 are removably engaged to the inner surface of top 20 via a row of fasteners 30 , such as snaps. Arches 28 are formed by inserting a resilient planer material, such as a plastic sheet, into enclosure 12 , bending the material into an arcuate shape, and then snapping the material into place. The resiliency of arches 28 insures that top panel 20 is maintained in an arcuate shape, yet allows for carrier 10 to be flexible. Additionally, removal of arches 28 allows carrier 10 to be nearly completely flattened for storage or transport when a pet is not inside enclosure 12 . An inflexible bar 31 , such as an aluminum rod, is positioned along the apex of top panel 20 to provide longitudinal stability to carrier 10 . Less rigid material, such as plastic, may be used instead of aluminum for a smaller carrier.
The rigidity of floor panel 14 is accomplished by a rigid bottom 32 having a strip of adhesive 34 , such as VELCRO®, for releasable attachment to a tray 36 ( FIG. 5 ). Tray 36 may have a rim for containing fluids, thus avoiding the need for the one inch margin between the releasable portion of side panels 16 and 18 and floor panel 14 . As seen in FIG. 5 , tray 36 contains a washable pad 38 releasably attached to tray 36 . Referring back to FIG. 6 , four studs 40 are interconnected through floor panel 14 to bottom 30 and extend outwardly from carrier 10 . Wheels (not shown) may be attached to floor panel 14 in lieu of studs 40 .
The transport of carrier 10 may be accomplished by at least three separate systems, which may be used individually or in concert. As seen in FIG. 1 , two rows of handle webbing 42 are secured to front and back of carrier 10 along the lower portions of top panel 20 . Handle webbing 42 is sewn or stitched directly to floor panel 14 and the lower portion of top panel 20 , and is further secured by a rivet 44 at the point where it detaches from top 20 . Rows of handle webbing 42 extend outwardly and independently from carrier 10 at rivet 44 and interconnect on either side of carrier 10 to form a pair of opposing handles 46 . A padded hand strap 48 may be secured around handles 46 by releasable means, such as VELCRO®, to keep handles 46 together and improve user comfort.
Carrier 10 may also be transported by engaging an adjustable shoulder strap 50 to D-rings 52 positioned on either side of the upper most portion of top panel 20 . Shoulder strap 50 preferably contains a padded cushion 54 and a pair of tangle-free swivel hooks 56 for attachment to D-rings 52 .
Referring to FIG. 3 , carrier 10 may also be transported by a backpack system 58 that is engageable with carrier 10 . As seen in FIG. 1 , the front side of carrier 10 contains two front buckles 60 positioned beneath webbing 42 . As seen in FIG. 2 , the rear side of carrier 10 contains a pair of upper strap buckles 62 attached to an intermediate portion of top panel 20 and two waist buckles 64 positioned on the lowermost portion of top panel 20 proximate to side panels 16 and 18 and floor panel 14 .
As seen in FIG. 3 , backpack system 58 comprises two adjustable straps 66 having two sets of buckles 68 and 70 at one end and a single set of buckles 72 at the opposite ends. As seen in FIG. 7 , the two sets of buckles 68 and 70 are engageable with upper strap buckles 62 on the rear of carrier 10 and front buckles 60 on the front of carrier 10 , respectively. Single set of buckles 72 is engageable with waist buckles 64 on the rear of carrier 10 . Referring back to FIG. 3 , backpack system 58 additionally includes an adjustable waist strap 74 that is attached to and interconnects the ends of straps 66 having single set of buckles 72 . The six points of connection to carrier 10 provided by backpack system 58 allows carrier 10 to be maintained in a level position when worn by a pet owner by adjusting the length of the various straps accordingly.
Carrier 10 also includes various elements for improving the convenience and ease by which pets and pet related paraphernalia are transported. As seen in FIG. 1 , a water bottle holder 75 may be provided on a portion of side panel 16 below mesh window 22 . Holder 75 preferably contains an elastic opening sized to accommodate and secure conventionally sized drink bottles. An additional elastic strap (not shown) may be positioned above holder 75 to retain a water bottle in place and a small opening (not shown) into enclosure 12 may be provided to allow a pet to access the water bottle in holder 75 .
As seen in FIG. 2 , a mesh pocket 76 with an elastic opening may be provided on the exterior surface of side panel 18 . As seen in FIG. 6 , flexible curtains 78 may be positioned on the inside surface of enclosure 12 . Curtains 78 can be rolled up and down and held in either position by VELCRO® strips 80 .
As seen in FIG. 1 , carrier 10 may also comprise a large pocket 82 with a releasable cover 84 positioned on the front surface of top panel 20 for the storage of additional materials, such as a can of pet food, a leash, treats, or similar items. An intermediate portion of top panel 20 may further include a mesh window 86 and corresponding flap 88 having a strip of VELCRO® for fastening in an open or closed position. Mesh window 86 is preferably positioned in the upper portion of top panel 20 to allow visibility into and out of enclosure 12 . Mesh window 86 is particularly useful when carrier 10 is placed underneath a seat, such as on an airplane, or when strapping in an adjoining seat, such as in an automobile. Mesh window 86 may be releasably attached to top panel along one or more sides by a double zipper or the like which allows access to enclosure 12 but does not allow a pet to force the zipper open from the inside. Flap 88 should be slightly larger than opening formed by window 86 to prevent the entry of precipitation into enclosure 12 .
Backpack system 58 may further include D-rings 90 ( FIG. 3 ) for attaching accessories, such as a cellular phone pouch or waste bag pouch. As seen in FIG. 4 , an accessory pouch 92 adapted for attachment to system 58 includes a tangle free, 360 degree swivel hook 94 for attachment to D-rings 90 .
As seen in FIG. 1 , a D-ring 96 is permanently attached or sewn to the interior of carrier 10 , preferably onto the inner surface of top panel 20 , and a leash 98 is secured to D-ring 96 . The leash preferably has a tangle free swivel hook at both ends and is adjustable to various lengths to restrain a pet inside enclosure 12 while allowing limited movement when any one of mesh window 88 , side panel 16 , or side panel 18 are open.
As seen in FIGS. 2 and 6 , top panel 20 further comprises a zippered opening 100 that communicates with a pouch 102 positioned on the inside of top panel 20 to allow for the insertion of a heating pad, a cooling pad, an air freshener, or an odor remover (not shown). Pouch 102 can optionally used for storage of personal items. Rear portion of top panel 20 may further contain a storage compartment having a releasable flap and various of pouches or holders designed for holding personal items, such as stationary supplies pens or pencils. Rear portion of top panel 20 may also include a pair of loops 104 ( FIG. 2 ) for attachment to an adjustable bicycle handle, car seat belt, or luggage rack. | A pet carrier for transporting an animal includes a floor panel having a substantially rigid bottom, a pair of side panels each having a lower edge and an upper portion, the lower edges of each side panel attached to opposite ends of the floor panel, and an arcuate top panel having a pair of oppositely located lateral edges, a pair of oppositely located ends, and an inner surface, the ends being fixedly attached to the floor panel and the lateral edges being releasably attached to the side panels. At least two arches are detachably engaged to the top panel inner surface and spaced above the floor panel, the arches being formed from a resiliently planar material and bent to conform with the arcuate top panel. An inflexible bar is positioned along an apex of the top panel inner surface for providing longitudinal stability to the carrier. | 0 |
TECHNICAL FIELD
The present invention relates to analgesic compositions comprising capsaicin or a capsaicin analog combined with a centrally-acting narcotic analgesic selected from the class of opioids. These compositions, when administered to humans or lower animals, provide a synergistic analgesic effect while minimizing undesirable side effects and toxicity.
Capsaicin and its derivatives appear to produce an analgesic effect through a mechanism largely unrelated to that of the other two categories of analgesics, and do not appear to involve the endorphin-enkephalin system, as the narcotics do. Since both capsaicin and the narcotics produce an analgesic effect, although apparently through different mechanisms, it might be expected that their combined effect would be at best additive. However, tests have shown that the analgesic effect of the combination is not merely the sum of the effects of each component, but rather an unexpected, greatly enhanced synergistic effect. Furthermore, the undesirable side effects of the two categories of analgesics are not closely related and the addition of the second analgesic does not appear to potentiate the side effects of the first. It is therefore possible to combine the two analgesics in such a dosage as to provide greatly enhanced analgesia with negligible side effects. Depending on the dosages employed, the capsaicin may either potentiate the degree of analgesia obtainable using the narcotic alone, or it may induce analgesia at dosages where no analgesic effect is obtained from either component alone.
BACKGROUND OF THE INVENTION
Traditionally, analgesics have fallen into two broad categories. Simple, non-narcotic analgesics, such as aspirin, which appear to work by inhibition of prostaglandin synthetase, are effective against pain of integumental origin such as headache and muscle aches, but are often ineffective in controlling deeper, more intense pain. The narcotic analgesics appear to work through interaction with the endorphin-enkephalin system of the central nervous system and are useful in controlling pain which is too intense to be controlled by the weaker, non-narcotic analgesics. However, centrally-acting narcotic analgesics have several serious undesirable side effects, including the development of physical dependence and tolerance, sedation, respiratory depression, hypotension, increase in cerebrospinal fluid pressure, nausea, vomiting and constipation. Therefore, it is desirable to administer the smallest effective dose possible. In some patients, particularly the chronically ill, the narcotic side effects make it impossible to administer dosages sufficient to adequately control pain over the required time period.
This invention combines capsaicin or a capsaicin derivative with a narcotic analgesic, resulting in a synergistic increase in analgesia without a corresponding increase in side effects. This makes it possible to control pain which cannot be adequately controlled by narcotics alone due to the severity of the undesirable side effects.
It has been recently discovered that capsaicin, a natural product of certain species of the genus Capsicium, induces analgesia. Capsaicin (8-methyl-N-vanillyl-6E-nonenamide) and "synthetic" capsaicin (N-vanillyl-nonanamide) are disclosed as analgesics in U.S. Pat. No. 4,313,958, LaHann, issued Feb. 2, 1982. Analgesic activity of capsaicin has also been discussed in the chemical and medical literature, including Yaksh, et al, Science, 206, pp 481-483 (1979); Jancso, et al, Naunyn-Schmiedeberg's Arch. Pharmacol., Vol. 311, pp 285-288 (1980) and Holzer et al, Eur. J. Pharm. Vol. 58, pp 511-514 (1979). U.S. Pat. No. 4,238,505, Nelson, issued Dec. 9, 1980, discloses 3-hydroxyacetanilide for use in producing analgesia in animals. U.S. Pat. application Ser. No. 359,464, LaHann, et al, filed Mar. 18, 1982, now, U.S. Pat. No. 4,424,206, issued Jan. 3, 1984, describes hydroxyphenylacetamides with analgesic and anti-irritant activity. Similarly, analgesic and anti-irritant activity is disclosed for N-vanillylsulfonamides in U.S. Pat. No. 4,401,663, Buckwalter, et al, issued Aug. 30, 1983; N-vanillylureas in U.S. Pat. application Ser. No. 381,672, Buckwalter, et al, filed May 25, 1982, now U.S. Pat. No. 4,460,602, issued July 17, 1984; N-vanillylcarbamates in U.S. patent application Ser. No. 384,685, Buckwalter, et al, filed June 3, 1982, now U.S. Pat. No. 4,443,473, issued April 17, 1984; N-[(substituted phenyl)methyl]alkynlamides in U.S. patent application Ser. No. 514,204, Janusz, et al, filed July 14, 1983, now abandoned; methylene substituted N-[(substituted phenyl)methyl]alkanamides in U.S. Pat. application Ser. No. 514,205, Janusz, et al, filed July 14, 1983; N[(substituted phenyl)methyl]-cis-monounsaturated alkenamides in U.S. patent application Ser. No. 514,206, LaHann, et al, filed July 14, 1983, now U.S. Pat. No. 4,498,848, issued Jan. 15, 1985; and N-[substituted phenyl)methyl]diunsaturated amides in U.S. patent application Ser. No. 514,207, LaHann, et al, filed July 14, 1983, now abandoned.
None of these references, however, suggest in any way the desirability of concurrent administration of capsaicin or a capsaicin derivative and an opioid. In fact, just the opposite is suggested. Both U.S. Pat. No. 4,313,958 (LaHann) and Yaksh et al suggest that the mechanism of capsaicin-induced analgesia is totally unrelated to that of narcotic-induced analgesia. It is extremely hard to predict when a synergistic effect will be obtained from two pharmaceutical compositions which take effect through different mechanisms. Furthermore, the only references which considered the effect of capsaicin pretreatment on morphine analgesia suggest that, when young rats are pretreated with capsaicin and then injected with morphine 1-4 months later, there is generally no effect (Holzer et al), and that in some cases pretreatment with capsaicin can in fact decrease morphine analgesia (Jancso et al).
Although there are several patents which disclose analgesic compositions containing a narcotic combined with another analgesic compound, none of these compounds has a structure at all similar to that of capsaicin. See U.S. Pat. Nos. 4,404,210, Schmidt, issued Sept. 13, 1983; 4,083,981, Yamamoto, issued April 11, 1978; 4,315,936, Capetola et al, issued Feb. 16, 1982; 4,379,789, Capetola et al, issued April 12, 1983.
Thus, based on the art, one would have expected the combination of capsaicin or a capsaicin analog with an opioid analgesic to produce no enhancement of the analgesic effect at best, and at worst, an antagonistic response. Yet, surprisingly, it has now been found that such a combination results in a synergistic increase in analgesia.
SUMMARY OF THE INVENTION
It has now been found that combinations of capsaicin derivatives of the general formula ##STR1## wherein R 1 is OH or OCH 3 , R 2 is OH or a short-chain ester, ester, X is ##STR2## and R is a C 5 -C 11 alkyl, C 5 -C 1 1 alkenyl, C 11 -C 23 cis alkenyl, C 11 -C 23 alkynyl, C 11 -C 23 alkadienyl, or C 11 -C 23 methylene substituted alkane, with an opioid analgesic at weight ratios of capsaicinoid to opioid from about 20,000:1 to 1:20, and preferably from about 10,000:1 to 1:10, depending on the relative strength of the opioid, provide unexpectedly enhanced analgesiq activity in humans and lower animals without a corresponding increase in undesirable side effects.
Another aspect of the present invention comprises the method of alleviating pain in humans and lower animals by concurrent administration of a safe and effective amount of a capsaicinoid and an opioid, as described above.
DETAILED DESCRIPTION OF THE INVENTION
A. Definitions
By the term "comprising" as used herein is meant that various other inert ingredients, compatible drugs and medicaments, and steps can be employed in the compositions and methods of the present invention as long as the critical capsaicinoid/opioid combination is present in the compositions and is used in the manner disclosed. The term "comprising" thus encompasses and includes the more restrictive terms "consisting essentially of" and "consisting of" which characterize the use of the compositions and methods disclosed herein.
By "compatible" herein is meant that the components of the composition are capable of being commingled without interacting in a manner which would substantially decrease the analgesic efficacy of the total composition under ordinary use situations.
By "administer concurrently" is meant either the administration of a single composition containing both the capsaicinoid and the opioid, or the administration of the capsaicinoid and the opioid as separate compositions within a short enough time period that the effective result is equivalent to that obtained when both compounds are administered as a single composition. Normally this would involve two separate dosages given within 10 minutes of each other. However, since many capsaicinoids retain effectiveness over unusually long time periods (possibly up to 3 days in some cases) and most opioids provide effective analgesia for relatively short time periods (4-8 hours), it may be desirable in some cases to implement a therapeutic regimen whereby each component is administered according to a schedule determined by its own period of analgesic effectiveness in order to maintain optimum effectiveness of the combination. The preferred method of administration is as a single composition.
All percentages and ratios herein are by weight unless otherwise specified.
B. Compositions
The compositions of the present invention comprise a safe and effective amount of a combination of:
(a) capsaicin or a capsaicin analog,
(b) an analgesic selected from the group of opioids, and
(c) a pharmaceutically-acceptable carrier.
A safe and effective amount of the composition is that amount which provides analgesia, thereby alleviating or preventing the pain being treated at a reasonable benefit/risk ratio, as is intended with any medical treatment. Obviously, the amount of analgesic used will vary with such factors as the particular condition that is being treated, the severity of the condition, the duration of the treatment, the physical condition of the patient, the nature of concurrent therapy (if any), the method of administration, and the specific formulation and carrier employed.
Weight ratios of capsaicinoid to opioid vary widely due to the great variation in strength among opioids. A preferred weight ratio for a capsaicinoid combined with an extremely potent opioid, such as fentanyl or etorphine, could be as high as 20,000:1, while a preferred weight ratio for a capsaicinoid combined with one of the weaker opioids, such as codeine or propoxyphene, could be as low as 1:20. Generally, weight ratios will be higher for injectable opioids than for opioids which are administered orally due to the higher potency of the injectable opioids. As a representative example, weight ratios of capsaicinoid: morphine may range from about 1200:1 to about 1:3, with preferred ranges from about 50:1 to about 1:1. Weight ratios of capsaicinoid:codeine may range from about 20:1 to about 1:10, with preferred ranges from about 7:1 to about 1:2. The ratio of capsaicinoid to opioid is also dependent upon the type and severity of the pain being treated.
By the term "capsaicin or a capsaicin analog" or "capsaicinoid" is meant a compound of the general formula ##STR3## wherein R 1 is selected from the group consisting of OH and OCH 3 , R 2 is selected from the group consisting of OH and ##STR4## R 3 is selected from the group consisting of a C 1 -C 4 alkyl, phenyl and methyl, X is selected from the group consisting of ##STR5## and R is selected from the group consisting of a C 5 -C 11 alkyl, C 5 -C 11 alkenyl, C 11 -C 23 cis alkenyl, C 11 -C 23 alkynyl, C 11 -C 23 alkadienyl and C 11 -C 23 methylene substituted alkane.
Preferred compounds include those wherein both R 1 and R 2 are OH and X is ##STR6## and those wherein R 1 is OCH 3 , R 2 is OH or ##STR7## Preferred R groups include C 7 -C 10 alkyls and trans alkenyls, and C 16 -C 21 cis alkenyls and alkadienyls. The preferred moieties within these groups include C 8 H 17 , C 9 H 17 and C 17 H 33 . Preferred capsaicin analogs include N-vanillyl-alkadienamides, N-vanillyl-alkanedienyls, and N-vanillyl-cis-monounsaturated alkenamides. A particularly preferred capsaicinoid is N-vanillyl-9-octadecenamide (N-vanillyloleamide).
Preferred capsaicin analogs and methods for their preparation are described in the following U.S. Patents and Patent Applications, all incorporated by reference herein: Capsaicin (8-methyl-N-vanillyl-6E-nonenamide) and "synthetic" capsaicin (N-vanillylnonanamide) are disclosed as analgesics in U.S. Pat. No. 4,313,958, LaHann, issued Feb. 2, 1982. European Patent Application No. 0089710, LaHann, et al, published Sept. 28, 1983, describes hydroxyphenylacetamides with analgesic and anti-irritant activity. Similarly, analgesic and anti-irritant activity is disclosed for N-vanillylsulfonamides in European Patent Application No. 0068591, Buckwalter, et al, published Jan. 5, 1983; N-vanillylureas in European patent Application No. 0068590, Buckwalter, et al, published Jan. 5, 1983; N-vanillylcarbamates in European Patent Application No. 0068592, Buckwalter, et al, published Jan. 5, 1983; N-[(substituted phenyl)methyl]alkynylamides in U.S. patent application Ser. No. 514,204, Janusz, et al, filed July 14, 1983; methylene substituted-N-[(substituted phenyl-)methyl]-alkanamides in U.S. patent application Ser. No. 514,205, Janusz, et al, filed July 14, 1983; N[(substituted phenyl)methyl]-cis-monounsaturated alkenamides in U.S. patent application Ser. No. 514,206, LaHann, et al, filed July 14, 1983, now U.S. Pat. No. 4,498,848, issued Jan. 15, 1985; and N-[(substituted phenyl)methyl]diunsaturated amides in U.S. patent application Ser. No. 514,207, LaHann, et al, filed July 14, 1983.
By "opioid" is meant any exogenous substance which binds specifically to any of several subspecies of opioid receptors. This term is used to designate a group of drugs that are, to varying degrees, opium or morphine-like in their properties, and includes morphine, analgesic morphine derivatives and their pharmaceutically-acceptable salts, and synthetic drugs producing a morphine-like effect. The pharmacological properties and therapeutic uses of the analgesics included within the classification of opioids are described in detail in Goodman and Gilman, "Opioid Analgesics and Antagonists", The Pharmacological Basis of Therapeutics, 6th Ed., Ch. 22 (1980), incorporated by reference herein.
Opioids which may be utilized in the present invention include, but are not limited to, morphine, codeine, hydromorphone, oxycodone, hydrocodone, oxymorphone, propoxyphene, levorphanol, meperidine, fentamyl, methadone, pentazocine, butorphanol, and nalbuphine. Particularly preferred opioids include morphine, codeine, oxycodone, hydrocodone, fentamyl, methadone and meperidine.
By "pharmaceutically-acceptable salts" is meant those salts which are toxicologically safe for topical or systemic administration. These include phosphate, sulfate, lactate, napsylate, and hydrochloride salts.
By "pharmaceutically acceptable carrier" is meant a solid or liquid filler, diluent or encapsulating substance which may be safely used in systemic or topical administration. Depending upon the particular route of administration, a variety of pharmaceutically-acceptable carriers, well known in the art, may be used. These include solid or liquid fillers, diluents, hydrotropes, surface-active agents, and encapsulating substances. The amount of the carrier employed in conjunction with the capsaicinoid/opioid combination is sufficient to provide a practical quantity of material per unit dose of analgesic.
Pharmaceutically-acceptable carriers for systemic administration, that may be incorporated into the compositions of this invention, include sugars, starches, cellulose and its derivatives, malt, gelatin, talc, calcium sulfate, vegetable oils, synthetic oils, polyols, alginic acid, phosphate buffer solutions, emulsifiers, isotonic saline, and pyrogen-free water. Specific pharmaceutically-acceptable carriers are described in the following U.S. Patents and Patent Applications, all incorporated by reference herein: U.S. Pat. No. 4,401,663, Buckwalter, et al, issued Aug. 30, 1983; and European Patent Application Nos. 0089710, LaHann, et al, published Sept. 28, 1983; and 0068592, Buckwalter, et al, published Jan. 5, 1983. Preferred carriers for parenteral administration include propylene glycol, ethyl oleate, pyrrolidone, aqueous ethanol, sesame oil, corn oil, and combinations thereof.
Various oral dosage forms can be used, including such solid forms as tablets, capsules, granules and bulk powders. Tablets can be compressed, tablet triturates, enteric-coated, sugar-coated, film-coated or multiple compressed, containing suitable binders, lubricants, diluents, disintegrating agents, coloring agents, flavoring agents, flow-inducing agents, and melting agents. Liquid oral dosage forms include aqueous solutions, emulsions, suspensions, non-aqueous solutions and/or suspensions reconstituted from non-effervescent granules and effervescent preparations reconstituted from effervescent granules, containing suitable solvents, preservatives, emulsifying agents, suspending agents, diluents, sweeteners, melting agents, coloring agents, and flavoring agents. Preferred carriers for oral administration include ethyl oleate, aqueous methylcellulose, gelatin, propylene glycol, cottonseed oil and sesame oil. Specific examples of pharmaceutically-acceptable carriers and excipients that may be used to formulate oral dosage forms, which may be used in formulating oral dosage forms containing monoalkenamides are described in U.S. Pat. No. 3,903,297. Robert, issued Sept. 2, 1975, incorporated by reference herein. Techniques and compositions for making solid oral dosage forms are described in Marshall, "Solid Oral Dosage Forms", Modern Pharmaceutics, Vol. 7, (Banker and Rhodes, editors), pp 359-427 (1979), incorporated by reference herein.
Specific systemic and topical formulations useful in this invention are described in the following U.S. Patents and Patent Applications, relating to specific capsaicin analogs and methods of treatment, which are incorporated by reference herein: U.S. Pat. No. 4,401,663, Buck walter et al, issued Aug. 30, 1983; and European Patent Application Nos. 0089710; LaHann, et al, published Sept. 28, 1983; 0068590, Buckwalter, et al, published Jan. 5, 1983; and 0068592, Buckwalter, et al, published Jan. 5, 1983. Topical vehicles, useful herein, are disclosed in the following U.S. Patent Applications, incorporated by reference herein: "Improved Penetrating Topical Pharmaceutical Compositions Combining 1-dodecylazacycloheptan-2-one", Ser. No. 506,275, Cooper, filed June 21, 1983; "Penetrating Topical Pharmaceutical Compositions Containing N-(1-hydroxyethyl)-pyrrolidone", Ser. No. 506,273, Cooper, filed June 21, 1983; "Penetrating Topical Pharmaceutical Compositions", Ser. No. 516,005, Cooper et al, filed July 20, 1983; and "Compounds Useful for Producing Analgesia", Ser. No. 514,206, LaHann and Buckwalter, filed July 14, 1983, now U.S. Pat. No. 4,498,848, issued Jan. 15, 1985.
C. Methods for Producing Analgesia
The present invention also encompasses methods for providing analgesia in humans or lower animals by administering concurrently to the human or lower animal in need of such treatment a safe and effective amount of a capsaicinoid/opioid combination or a composition containing the same. Dosages required, as well as methods of administration, are dependant on the type of opioid employed. Dosages administered may be expected to vary widely due to the wide variations in potency among the various opioids. Dosage is also dependant on the severity of the pain which must be prevented or alleviated, the physical condition of the patient, the relative severity and importance of adverse side effects, and other factors within the judgment of the physician.
The maximum dosage of the preferred capsaicin analogue vanillyloleamide (VO) which would normally be administered orally to an average adult is about 2000 mg (33 mg/kg). The minimum effective dosage is about 100 mg, (1.3 mg/kg). The maximum dosage of codeine phosphate which would normally be administered to the average adult is about 120 mg (2 mg/kg) while the minimum effective dosage is about 30 mg (0.5 mg/kg). Weight ratios of capsaicinoid to codeine may range from about 20:1 to about 1:10. Thus, the maximum allowable dosage of the combination will range from about that of codeine phosphate, 120 mg (2 mg/kg) to about that of vanillyloleamide, 2000 mg (33 mg/kg), depending on the relative proportions used. It should be noted that a sub-effective dosage of one compound may effectively potentiate the other compound; therefore, less-than-minimum dosages may be utilized in some cases. Thus, when dealing with safe and effective dosage levels of the present invention, it is more appropriate to speak of safe and effective dosages of the combination rather than of the individual components. The maximum dosage of VO which can be administered to an average adult by subcutaneous or intramuscular injection is about 400 mg (6.6 mg/kg). The maximum allowable dosage of morphine sulfate is about 30 mg (0.5 mg/kg). Weight ratios of capsaicinoid to morphine may range from about 1200:1 to about 1:3. Thus, the maximum allowable dosage will be effectively that of the capsaicinoid component, about 400 mg (6.6 mg/kg).
The compositions of this invention can be used to treat and prevent pain, and to provide analgesia in various disorders at the deeper structures, muscles, tendons, bursa and joints associated with disease and trauma, and in various other conditions in which compounds such as codeine and morphine have heretofore been used to alleviate pain and discomfort.
The compositions of the instant invention can be administered topically or systemically. Systemic application includes any method of introducing the composition into the tissues of the body, e.g., intrathecal, epidural, intramuscular, transdermal, intravenous, intraperitoneal, subcutaneous, sublingual, and oral administration.
The following non-limiting Examples illustrate the compositions, methods of treatment, and uses of the present invention.
EXAMPLE I
An analgesic composition for oral administration was made with the following proportions of the narcotic opiate codeine phosphate and the non-narcotic capsaicin analog vanillyl-9E-octadecenamide:
______________________________________N--vanillyl-9E-octadecenamide 60.00 mgCodeine phosphate 18.33 mgMethylcellulose 30.00 mgSaline 6.0 ml______________________________________
The methylcellulose suspending agent and the codeine phosphate were dispersed in the saline and the octade-cenamide was suspended in the resulting solution with the aid of sonication. The preparation was dosed orally to male mice weighing approximately 25 g at a dose sufficient to deliver 30 mg/kg codeine phosphate and 100 mg/kg of the octadecenamide. Analgesic activity was demonstrated using the phenylquinone writhing test.
EXAMPLE II
An analgesic composition for oral administration was made with the following proportions of the narcotic propoxyphene hydrochloride and the non-narcotic capsaicinoid n-vanillyl-9E-octadecenamide:
______________________________________N--vanillyl-9E-octadecenamide 120 mgPropoxyphene HCl 120 mgMethylcellulose 30 mgSaline 6.0 ml______________________________________
Propoxyphene was dissolved in a methylcellulosesaline mixture and the octadecenamide was then suspended in the solution by the use of sonication. The preparation was dosed orally to male mice weighing approximately 25 g at a dose sufficient to deliver 200 mg/kg propoxyphene HCl and 200 mg/kg codeine phosphate. Analgesia was demonstrated using the phenylquinone writhing test.
EXAMPLE III
An analgesic composition for intramuscular or subcutaneous injection was made using the following proportions of the narcotic opiate morphine sulfate and the non-narcotic capsaicin analog N-vanillyl-9E-octadecenamide:
______________________________________N--vanillyl-9E-octadecenamide 11.3 mgMorphine sulfate 0.45 mgEthanol 0.3 mlTween 80 0.3 mlSaline 2.4 ml______________________________________
The composition was made by dissolution of the morphine in the saline, dissolution of the octadecenamide in the ethanol and Tween 80 together, and admixture of the two solutions to yield a homogeneous solution containing both drugs in a final ratio of 25 part octadecenamide to 1 part morphine sulfate. 0.2 ml of the composition was injected subcutaneously into a 30 g male mouse (dosage=26 mg/kg). Analgesia was produced.
EXAMPLE IV
A composition for oral administration is made with the following components:
______________________________________N--vanillyl-11E-octadecenamide 100 mgCodeine phosphate 30 mgStarch 10 mgMagnesium stearate 0.5 mg______________________________________
The above ingredients are dry-mixed and a capsule is filled with the mixture. The capsule is then administered to a 60 kg human subject, producing analgesia.
Substantially similar results are produced when the octadecenamide is replaced, in whole or in part, by capsaicin; N-vanillyl-9Z-octadecenamide; N-vanillyl-9E-octadecenamide; N-[(4-acetoxy-3-methoxyphenyl)methyl]-9Z-octadecenamide; N-vanillyl-(Z,Z)-9,12-octadecadienamide; N-vanillyl-(E,E)-9,12-octadecadienamide; N-[(4-acetoxy-3-methoxyphenyl)methyl]-(E,E)-9,12-octadecadienamide; N-vanillyl-(E,E)-10,13-nonadecadienamide; N-vanillyl-9-octadecynamide; 9-methylene-N-octadecanamide; 9-methylene-N-[(4-acetoxy-3-methoryphenyl)-methyl]octadecanamide; 4-acetoxy-3-methoxy-benzyl nonamide, or octyl 3,4-dehydroxyphenylacetamide. Similar results are also obtained, after adjusting the dosage to compensate for differences in the relative strength of the opioid, when the codeine is replaced, in whole or in part, by propoxyphene HCl, oxycodone, hydrocodone, dihydrocodeine, fentanyl, methadone or meperidine.
EXAMPLE V
A composition for intramuscular injection is made with the following components:
______________________________________N--vanillyl-9,12,15[E,E,E]-octadecatrienamide 25 gOxycodone free base 1 gSesame oil 1000 mlBenzyl alcohol 15 ml______________________________________
The above ingredients are admixed by simple dissolution and 1.0 ml portions of the admixture are placed in pre-packaged sterile syringes. 1.0 ml of the composition is administered to a 70 kg human subject by intra-muscular injection, producing analgesia.
EXAMPLE VI
A composition for intramuscular administration is made with the following components:
______________________________________N--vanillyl-9E-octadecenamide 25 gMorphine sulfate 1 g (26 g/100 ml carrier)Carrier (percent by weight)Propylene glycol 72%Polyethylene glycol 17%Sterile water 10%Benzyl alcohol 1%______________________________________
The composition is made by simple dissolution of the morphine sulfate in the water, simple dissolution of the octadecenamide in the propylene glycol, and admixture of the resulting solutions and other components. A 60 kg human is injected by deep intramuscular injection with 1.5 ml of the composition, producing analgesia.
EXAMPLE VII
An analgesic composition for deep intramuscular administration is made with the following ingredients:
______________________________________N--vanillyl-9,12[Z,Z]-octadecadienamide 25 gMerperidine HCl 1.5 gPropylene glycol 2000 mlSterile water 300 mlBenzyl alcohol 46 ml______________________________________
The meperidine is dissolved in the sterile water, the octadecadienamide is dissolved on the propylene glycol, and the resulting solutions are admixed with the benzyl alcohol to give a homogeneous solution. A 70 kg human subject is injected intramuscularly with 1.0 ml of this composition, producing analgesia.
Effectiveness in Providing Analgesia
1. Mouse Hot Plate Tests
The extent of analgesia obtained was determined using the mouse hot plate (MHP) analgesic model. Mice were placed one at a time on a heated copper surface (55.0±0.5° C.) and their reactions were observed. The exposure time required to elicit either a rapid fanning or licking of any paw was used to measure the pain threshold. Analgesic effect was determined by comparing the reaction times of animals treated only with a vehicle control (typically 4.5-5.5 seconds) with the reaction times of the drug treated animals. To avoid tissue damage, rodents not responding within 60 seconds were removed from the heated surface and assigned a 60 second reaction time.
Capsaicinoids were prepared in a vehicle composed of 10% ethanol, 10% Tween 80 (polyoxyethylene (20) sorbitan mono-oleate) and 80% saline. Narcotics were dissolved in 0.9% saline. Male CF-1 mice (25-35 g) were divided into groups of 8-10, and each animal was treated with either a capsaicinoid, a narcotic analgesic, a combination of both, or the vehicle alone. All treatments were administered by subcutaneous injection. Mice receiving a combination of a capsaicinoid and a narcotic were given two separate injections within sixty seconds of each other.
The synergistic analgesic effect obtained is illustrated by, but not limited to, the following examples:
EXAMPLE VIII
Capsaicin+Morphine Sulfate
Using the procedure outlined above, groups of 10 male CF-1 mice (25-35 g) were injected subcutaneously with either the vehicle (10% ethanol, 10% Tween 80 and 80% saline) alone, 4-hydroxy-3-methoxy benzylnonanamide (capsaicin), morphine sulfate, or a capsaicin-morphine sulfate combination (2 separate injections within 30 seconds of each other) in the quantities shown below. Hot plate reaction times were determined at 0.5, 1, 1.5, 2, 3, and 5 hours after the injections.
______________________________________ Average Reaction Time (Seconds) 5 0.5 1 1.5 2 3 hrs. postDosage hr. hr. hrs. hrs. hrs. injection______________________________________MS-1 mg/kg* 6.7 14.9 21.4 21.8 13.7 10.2MS-2 mg/kg 7.2 21.9 37.4 36.4 21.7 22.3Cap-5 mg/kg* 5.3 5.5 8.2 8.2 8.5 8.5MS-1 mg/kg + 8.4 23.6 58.4 56.6 45.0 19.0Cap-5 mg/kgVC* 5.0 5.0 5.0 5.0 5.0 5.0______________________________________ *MS = morphine sulfate Cap = capsaicin VC = vehicle control
EXAMPLE IX
Capsaicin+Codeine Phosphate
Groups of mice were injected and their pain thresholds determined as in Example VIII, but the narcotic tested was codeine phosphate instead of morphine sulfate.
______________________________________ Average Reaction Time (seconds) 5 0.5 1 1.5 2 3 hrs. postDosage hr. hrs. hrs. hrs. hrs. injection______________________________________CP-13.3 mg/kg* 8.8 20.4 32.5 32.5 29.9 19.2CP-26.6 mg/kg 10.4 24.3 45.0 43.4 34.5 27.4Cap-5 mg/kg 5.3 5.5 8.2 8.2 8.5 8.5CP 13.3 mg/kg + 8.9 24.6 60.0 59.4 55.5 24.7Cap 5 mg/kgVC 5.0 5.0 5.0 5.0 5.0 5.0______________________________________ *CP = codeine phosphate
EXAMPLE X
4-Hydroxy, 3-Methoxybenzyl
Δ 9E Octadecenamide+Morphine Sulfate
Groups of mice were injected and their pain thresholds determined as in Example VIII, but instead of capsaicin, the capsaicin analogue 4-hydroxy, 3-methoxybenzyl Δ 9E octadecenamide (N-vanilly-9E-octadecenamide or VO), ##STR8## was tested.
______________________________________ Average Reaction Time (seconds) 5 0.5 1 1.5 2 3 hrs. postDosage hr. hr. hrs. hrs. hrs. injection______________________________________MS-1 mg/kg* 6.7 14.9 21.4 21.8 13.7 10.2MS-2 mg/kg 7.2 21.9 37.4 36.4 21.7 22.3VO-25* mg/kg 5.3 5.5 7.2 7.3 7.5 7.5MS-1 mg/kg 8.9 23.2 53.8 53.3 46.1 18.0VO-25 mg/kgVC 5.0 5.0 5.0 5.0 5.0 5.0______________________________________ *MS = morphine sulfate *VO = vanillyloleylamide
EXAMPLE XI
4-Hydroxy-3-Methoxy Benzyl
Δ 9E Octadecenamide+Codeine Phosphate
Groups of mice were injected and their pain thresholds determined as in Example IX but instead of capsaicin, the capsaicin analogue 4-hydroxy, 3-methoxy benzyl Δ 9E octadecenamide N-vanillyl- 9E-octadecenamide or VO), was tested.
______________________________________ ##STR9## Average Reaction Time (seconds) post injection 0.5 1 1.5 2 3 5Dosage mg/kg hr. hr. hrs. hrs. hrs. hrs.______________________________________CP-13.3 mg/kg* 8.8 20.4 32.5 32.5 29.9 19.2CP-26.6 mg/kg 10.4 24.3 45.0 43.4 34.5 27.4VO-25 mg/kg* 5.3 5.5 7.2 7.3 7.5 7.5CP-13.3 mg/kg + 10.2 25.8 60.0 60.0 51.5 23.8VO-25 mg/kgVC 5.0 5.0 5.0 5.0 5.0 5.0______________________________________ *CP = codeine phosphate VO = vanillyloleylamide
EXAMPLE XII
4-Acetoxy-3-Methoxybenzyl-nonanamide+Morphine Sulfate
Groups of mice were injected and their pain thresholds determined as in Example VIII, but instead of capsaicin,the capsaicin analogue 4-acetoxy-3-methoxy benzylnonanamide, ##STR10## was tested.
______________________________________ Average Reaction Time (seconds) 3 hrs. postDosage 1 hr. 2 hrs. injection______________________________________MS-20 mg/kg* 22.1 16.3 8.5MS-20 mg/kg 22.9 18.5 8.3MS-35 mg/kg 49.5 38.3 12.3MS-35 mg/kg 51.2 42.4 12.5MBN-25 mg/kg* 5.7 5.5 5.2MBN-100 mg/kg 10.4 8.1 7.8MS-20 mg/kg + 29.9 22.7 13.6MBN-25 mg/kgMS-20 Mg/kg + 51.3 42.3 20.5MBN-100 mg/kgMS-35 mg/kg + 55.7 34.4 13.6MBN-25 mg/kgMS-35 mg/kg + 60.0 54.3 33.8MBN-100 mg/kgVC 5.0 5.0 4.9______________________________________ *MS = morphine sulfate MBN = 4acetoxy-3-methoxy benzylnonanamide
2. Phenylquinon Writhing Tests
The extent of analgesia obtained was determined using the phenylquinone writhing test model. Groups of eight male mice weighing between approximately 25 and 30 g were dosed orally with the analgesic composition to be tested. Identical groups of mice were dosed with control compositions. Three hours after this initial administration, the mice were injected intraperitoneally with a 0.2% solution of phenylbenzoquinone in aqueous ethanol. The ability of the analgesic compositions tested to relieve the discomfort induced was measured by counting the number of abdominal contractions, or "writhes", occurring in each mouse during a 10 minute period beginning 10 minutes after injection of the phenylbenzoquinone solution. The results are expressed as a percent of the "writhing" response observed in the vehicle control group.
EXAMPLE XIV
An analgesic composition for oral administration was made with the following proportions of the narcotic propoxyphene hydrochloride and the non-narcotic capsaicinoid
______________________________________N--vanillyl-9-octadecenamide 120 mgPropoxyphene HCl 120 mgMethylcellulose 30 mgSaline 6.0 ml______________________________________
Propoxyphene was dissolved in a methylcellulosesaline mixture and the octadecenamide was then suspended in the solution by the use of sonication. The analgesic efficacy of the combination was then contrasted with those of methylcellulose vehicle formulations lacking either the propoxyphene component, the octadecenamide component, or both. The mouse "writhing" method for assessing pain responses described above was used. The data, summarized in the following table, were normalized based on the vehicle control taken as 100.
______________________________________ %TREATMENT WRITHING RESPONSE______________________________________Methylcellulose Alone 100Propoxyphene HCl (200 mg/kg) 22Octadecenamide (200 mg/kg) 34Octadecenamide (400 mg/kg) 4Propoxyphene HCl (200 mg/kg) + 1Octadecenamide (200 mg/kg)______________________________________
The analgesic efficacy of this 1:1 combination of propoxyphene and vanillyl-9-octadecenamide is superior to that of either component alone as well as to that of an equal weight of octadecenamide. It is noteworthy that an equal weight dose of propoxyphene HCl (400 mg/kg) is highly toxic to mice, resulting in nacrosis and mortality.
EXAMPLE XV
An analgesic composition for oral administration was made with the following proportions of the narcotic opiate codeine phosphate and the non-narcotic capsaicin analog vanillyl-9E-octadecenamide;
______________________________________n-vanillyl-9E-octadecenamide 60.00 mgCodeine phosphate 18.33 mgMethylcellulose 30.00 mgSaline 6.0 ml______________________________________
The methylcellulose suspending agent and the codeine phosphate were dispersed in the saline and the octadecenamide was suspended in the resulting solution with the aid of sonication. The preparation was dosed orally to male mice at a dose sufficient to deliver 30 mg/kg codeine phosphate and 100 mg/kg of the octadecenamide.
The analgesic activity was assessed using the "writhing" assay described above. The activity of the combination was compared with that of similar formulations lacking the codeine component, the octadecenamide component, or both.
______________________________________TREATMENT % PAIN RESPONSE______________________________________Methylcellulose Alone 100Codeine phosphate (30 mg/kg) 95Octadecenamide (100 mg/kg) 45Codeine (30 mg/kg) + 3Octadecenamide (100 mg/kg)______________________________________
The analgesic efficacy of this 3.33:1 combination of codeine phosphate and octadecenamide is greater than the sum of the analgesic responses of its components when given separately. This dose of codeine when given alone is not analgesic in the mouse at all. 100 mg/kg of octadecenamide produces only 55% inhibition of the pain response in this test, yet a 97% inhibition of the pain response is obtained from the combination of the two components.
EXAMPLE XVI
An analgesic composition was made comprising a mixture of codeine phosphate and vanillyl-9-octadecenamide. The formulation was similar to that of Example XV, except that twice the levels of actives were used. This formulation and the formulations for comparison are described below:
______________________________________Combination FormulationN--vanillyl-9-octadecenamide 120.00 mgCodeine phosphate 36.36 mgMethylcellulose 30.00 mgSaline 6.0 mlN--vanillyl-9-octadecenamide reference formulationN--vanillyl-9-octadecenamide 120.00 mgMethylcellulose 30.00 mgSaline 6.0 mlLow dose codeine reference formulationCodeine Phosphate 36.00 mgMethylcellulose 30.00 mgSaline 6.0 mlHigh dose codeine reference formulationCodeine Phosphate 120.00 mgMethylcellulose 30.00 mgSaline 6.0 ml______________________________________
Preparation of dosing forms and assay for analgesia were conducted as in Example XV:
______________________________________TREATMENT % PAIN RESPONSE______________________________________Methylcellulose Alone 100Codeine Phosphate (60 mg/kg) 56Octadecenamide (200 mg/kg) 48Codeine phophate (60 mg/kg) + 14Octadecenamide (200 mg/kg)Codeine Phosphate (200 mg/kg) 21______________________________________
The 3.33:1 octadecenamide/codeine combination of Example XV is also highly effective at twice the dose. This formulation compares favorably in efficacy to a nearly equal weight oral dose of codeine. Very high oral doses of narcotics are often limited in usefulness due to constipation-producing side effects. Combination of low doses of codeine with N-vanillyl-9-octadecenamide produces efficacy equivalent to toxic narcotic doses. The octadecenamide and related capsaicin analogs do not produce opiate like side effects on the gastrointestinal tract.
Further, the combination offers additional benefits over either component alone. The slow but long acting capsaicinoid added to the rapid but short acting narcotic provides a rapid-acting, long-lasting analgesic formulation which cannot be duplicated by any single analgesic compound. | An analgesic composition comprising capsaicin or a capsaicin analog and an analgesic selected from the class of opioids is disclosed. This combination has been found to exhibit unexpectedly enhanced analgesic activity in humans and lower animals without a corresponding increase in undesirable side effects. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/333,688, filed on May 11, 2010, which is incorporated by reference herein in its entirety for all purposes.
TECHNICAL FIELD
Embodiments of the present invention relate to fluted woodturning tools of various kinds and types that are mounted into handles of varying lengths and are then used in a hand-held manner to shape a wooden workpiece while that workpiece is being rotated on a lathe.
BACKGROUND
Woodturning tools are used by all woodturners. With few exceptions, these tools are very similar within families (such as, for example, Bowl Gouges, Spindle Gouges, Spindle Roughing Gouges, Detail Gouges, and the like) for material selection and configuration. Thus there is no appreciable difference among sources for innate performance criteria. The few that utilize high performance materials are limited in supply and are considerably more expensive.
None of the currently available tools incorporate any improvements in mechanical design that would effectively damp vibration. None of the currently available tools incorporate variations of blade cross-section to improve blade beam strength. None of the currently available tools incorporate a manufacturing method that reduces the volume of expensive cutting edge material and thus reduces the overall material and manufacturing cost of the tool while maintaining its increased functionality. None of the currently available tools incorporate a strengthening bolster for the tool shaft that includes a vibration damping material such as flake graphite cast iron. None of the currently available tools incorporate a fiber and resin and aluminum composite handle which reduces initial weight, damps vibration, reduces vibration transfer to the user of the tool, and allows the user to adjust handle weight to suit his preference.
SUMMARY
According to embodiments of the present invention, a fluted woodworking lathe tool designed to include a laminated tool steel blade insert attached to a supporting substrate. The tool permits precision fitting of the blade/substrate composite into either a hollow oblong beam shaft or a round shaft. An inserted flute insert piece provides the transition from the blade to the oblong beam shaft and incorporates a beveled distal face which also functions as a chip deflection plate.
The finished tools may be made with and without a replaceable cutting edge insert assembly, for example.
The tools incorporate a hollow shaft that can be filled with metallic shot which damps vibration from the cutting edge and reduces vibration transfer to the handle. The oblong shape of the shaft significantly increases the vertical beam strength of the tool, thus reducing edge deflection during turning and thus reducing tool vibration. The tool shaft is attached to a cast iron bolster which provides structural support and further damps vibration from the cutting edge and reduces vibration transfer to the handle. The completed blade assembly is fitted into a handle utilizing a taperlock joint design. The removable handle is made of a concentric assembly of an extruded aluminum shaped insert that is encapsulated by a fiber reinforced composite sleeve with the distal end fitted with an insert that is shaped to accept the blade assembly and with the proximal end fitted with an insert shaped to accept end caps of various shapes. An internal threaded connection or some other connection mechanism may be included to secure the blade into the handle. The connection allows the user to quickly release and change blades thus utilizing one handle with multiple blades, according to embodiments of the present invention. The handle can be selectively filled with shot for damping as well as user preferred weight adjustment.
A primary tool option according to one embodiment of the present invention incorporates a replaceable cutting edge insert assembly which is attached to the oblong beam shaft with a gasketed loose tenon arrangement. This provides the user with a low cost way of refurbishing the tool once all the high-cost cutting edge material has been consumed.
Embodiments of the present invention include an improved fluted woodturning tool that significantly improves serviceability. Expensive wear-resistant cutting edge materials are machined in such a way that they can be adhered to and laminated with inexpensive materials and then further machined and processed in such a way that tool cutting edge performance is optimized by providing long cutting edge life and durability while keeping tool cost affordable. This adherence can be either through the use of adhesives or through the use of various metallurgical bonding techniques such as, but not limited, to brazing and/or soldering.
The void created in the tool blade during manufacturing may be stopped by the installation of a beveled deflection plate flute insert. This insert fortifies the strength of the tool as well as improves the chip extraction of those tools incorporating a fluted design.
The tool shaft may be a vertically oblong beam. This dramatically reduces tool deflection during turning and thus reduces the amplitude of any vibrations created within the tool.
The void created in the tool beam shaft during manufacturing may be filled with metallic shot. This shot damps vibration within the tool and reduces vibration transfer through the tool to the handle of the tool and thus to the hands of the tool user.
The tool shaft may be inserted into and adhered to a pearlitic matrix flake graphite cast iron bolster. This adherence can be achieved through the use of adhesives and/or through the use of various metallurgical bonding techniques such as, but not limited to, brazing or soldering.
The pearlitic matrix flake graphite cast iron bolster fortifies the strength of the tool, damps vibration within the tool, and reduces vibration transfer to the handle of the tool, according to embodiments of the present invention.
The exterior sleeve of the handle of the tool may be principally made of fiberglass fiber and a woven blend of carbon and aramid fibers, all of which are resin bonded into a rigid composite, according to embodiments of the present invention. The sleeve provides ergonomic compatibility to the human hand for both size and shape.
The interior of the handle of the tool may be compartmentalized through the use of an insert. These compartments may be selectively filled with metallic shot and thus permit a wide range of adjustments to handle weight at the discretion of the user.
The interior handle compartments may be selectively filled with metallic shot and thus provide additional vibration damping, again at the discretion of the user.
The cutting edge insert assembly may be made replaceable, thus reducing the lifetime cost of using the tool for the tool owner.
A fluted woodturning cutting blade may include one or more of the following features and/or characteristics, according to embodiments of the present invention:
A laminated composite of expensive wear resistant material and low cost support material, thus improving functionality while reducing cost.
A tool shaft with an optional oblong beam shaft shape which provides increased bending strength and thus reduces tool tip deflection and tool vibration while turning.
A hollow blade oblong beam shaft encapsulating metallic shot which dampens vibration.
Wherein the blade is held in a handle utilizing a precision taper lock bolster.
Wherein the bolster material provides increased vibration damping.
Wherein the bolster allows quick and easy blade interchangeability within the handle.
A handle for such a woodturning cutting blade may include one or more of the following features and/or characteristics, according to embodiments of the present invention:
Wherein the handle is a fiber reinforced composite which provides a reduction in initial overall tool weight.
Wherein the handle provides a mechanism for inclusion of metallic shot within the handle in such a way that provides vibration damping as well as user preferred weight adjustment.
Wherein the handle shape provides improved ergonomic comfort and compatibility for the user.
According to embodiments of the present invention, a fluted woodturning tool comprised of a cutting blade is assembled to a handle such that the combination of one or more of the features and/or characteristics described above give the user a vibration free or substantially vibration free tool.
A woodturning tool according to embodiments of the present invention includes a shaft having a shaft tip, wherein the shaft tip is made of a first metal, and a cutting edge insert, at least a portion of an outer surface of the cutting edge insert rigidly joined to an inner surface of the shaft tip, the cutting edge insert formed of a second metal, the cutting edge insert being fluted and sharpened to form a cutting edge for woodturning, wherein the second metal is different from the first metal, and wherein the second metal is more wear-resistant than the first metal.
The woodturning tool of paragraph [0022], wherein the second metal is high vanadium tool steel, and wherein the first metal is stainless steel.
The woodturning tool of paragraphs [0022] or [0023], wherein the second metal has a vanadium content from ten to fifteen percent, and wherein the first metal is a 400-series stainless steel.
The woodturning tool of any of paragraphs [0022] to [0024], wherein the shaft tip has an outer perimeter that is substantially uniform along its length, wherein the fluted cutting edge insert opens toward a first direction, and wherein a height of the shaft tip along the first direction is larger than a width of the shaft tip along a second direction perpendicular to the first direction.
The woodturning tool of any of paragraphs [0022] to [0025], wherein the shaft has an outer perimeter that is substantially the same along its length, and wherein the shaft outer perimeter is the same as the shaft tip outer perimeter.
The woodturning tool of any of paragraphs [0022] to [0026], wherein the at least a portion of the outer surface of the cutting edge insert is laminated to the inner surface of the shaft tip with brazing or polymeric adhesive.
The woodturning tool of any of paragraphs [0022] to [0027], wherein the shaft comprises an annular recess at least partially filled with metallic spherules.
The woodturning tool of any of paragraphs [0022] to [0028], wherein the tool permits addition of and withdrawal of the metallic spherules for user customized balancing and vibration dampening.
The woodturning tool of any of paragraphs [0022] to [0029], wherein the shaft tip is rigidly and reversibly coupled to the shaft to permit exchange of the shaft tip and the cutting edge insert for a new shaft tip and a new cutting edge insert.
The woodturning tool of any of paragraphs [0022] to [0030], further comprising a tenon and a gasket, wherein the gasket is located between a distal end of the shaft and a proximal end of the shaft tip, and wherein the tenon extends within the shaft, the shaft tip, and the gasket.
The woodturning tool of any of paragraphs [0022] to [0031], further comprising a flute insert, the flute insert rigidly joined to both the inner surface of the shaft tip and a proximal inner surface of the cutting edge insert.
The woodturning tool of any of paragraphs [0022] to [0032], wherein a distal face of the flute insert is beveled to provide chip deflection.
A method for manufacturing a woodturning tool according to embodiments of the present invention includes forming a shaft, forming a shaft tip of a first metal, inserting a cutting edge insert into the shaft tip, rigidly joining an outer surface of the cutting edge insert to an inner surface of the shaft tip, wherein the cutting edge insert is formed of a second metal, the cutting edge insert being fluted, and machining the cutting edge insert to form a cutting edge for woodturning, wherein the second metal is different from the first metal, and wherein the second metal is more wear-resistant than the first metal.
The method of paragraph [0034], wherein machining the cutting edge insert includes machining the cutting edge insert after rigidly joining the cutting edge insert to the shaft tip.
The method of paragraphs [0034] or [0035], wherein rigidly joining the outer surface of the cutting edge insert to the inner surface of the shaft tip includes laminating the outer surface of the cutting edge insert with the inner surface of the shaft tip by brazing or by applying a polymeric adhesive.
The method of any of paragraphs [0034] to [0036], further including forming an annular recess in the shaft, and at least partially filling the annular recess with metallic spherules.
The method of any of paragraphs [0034] to [0037], further including balancing the tool according to a user's preference by adding metallic spherules to the annular recess or withdrawing metallic spherules from the recess.
The method of any of paragraphs [0034] to [0038], further including forming the shaft tip and the shaft as a single unitary structure.
The method of any of paragraphs [0034] to [0039], further including rigidly and reversibly joining the shaft tip to the shaft to permit exchange of the shaft tip and the cutting edge insert for a new shaft tip and a new cutting edge insert.
The method of any of paragraphs [0034] to [0040], further including forming a flute insert, and rigidly joining the flute insert to both the inner surface of the shaft tip and a proximal inner surface of the cutting edge insert.
While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 (on Sheet 1 ) illustrates a perspective view of the finished cutting blade assembly of the tool that incorporates a replaceable cutting edge insert assembly, according to embodiments of the present invention.
FIG. 1A (on Sheet 3 ) illustrates a perspective view of the finished cutting blade assembly of the tool that incorporates a replaceable cutting edge insert assembly including a cutaway illustrating the inclusion of shot in the oblong beam shaft, according to embodiments of the present invention.
FIG. 1B (on Sheet 3 ) illustrates a longitudinal centerline cross section of the finished cutting blade assembly of the tool of FIG. 1 , according to embodiments of the present invention.
FIG. 1C (on Sheet 3 ) illustrates an end view from the distal end of the finished cutting blade assembly of the tool of FIG. 1 , according to embodiments of the present invention.
FIG. 2 (on Sheet 1 ) illustrates a perspective view of the cutting blade assembly of the tool that incorporates a replaceable cutting edge insert assembly prior to final machining, according to embodiments of the present invention.
FIG. 3 (on Sheet 1 ) illustrates a perspective exploded view of the cutting blade assembly of the tool of FIG. 2 , according to embodiments of the present invention.
FIG. 3A (on Sheet 2 ) illustrates a longitudinal centerline cross-section view of the oblong beam shaft tip taken along line A-A of FIG. 3D , without the round loose tenon and without the cutting edge insert, illustrating the drilled holes in this component, according to embodiments of the present invention.
FIG. 3B (on Sheet 2 ) illustrates a proximal end view of the oblong beam shaft tip illustrating the drilled hole for the round loose tenon, according to embodiments of the present invention.
FIG. 3C (on Sheet 2 ) illustrates a distal end view of the oblong beam shaft tip illustrating the drilled hole for the cutting edge insert, according to embodiments of the present invention.
FIG. 3D (on Sheet 2 ) illustrates a perspective view of the cutting blade assembly of the tool that shows the cutting edge insert assembled into the oblong beam shaft tip, according to embodiments of the present invention.
FIG. 3E (on Sheet 2 ) illustrates a longitudinal isometric exploded centerline cross-section view of the oblong beam shaft tip illustrating the drilled holes in this component, according to embodiments of the present invention.
FIG. 4 (on Sheet 1 ) illustrates a perspective view of the finished cutting blade assembly of the round shaft tool design type, according to embodiments of the present invention.
FIG. 4A (on Sheet 3 ) illustrates a perspective view of the finished cutting blade assembly of the round shaft tool design type including a cutaway illustrating the inclusion of shot in the oblong beam shaft, according to embodiments of the present invention.
FIG. 4B (on Sheet 3 ) illustrates a longitudinal centerline cross section of the finished cutting blade assembly of the round shaft tool of FIG. 4 taken along line H-H of FIG. 4 , according to embodiments of the present invention.
FIG. 4C (on Sheet 3 ) illustrates an end view from the distal end of the finished cutting blade assembly of the round shaft tool of FIG. 4 , according to embodiments of the present invention.
FIG. 5 (on Sheet 1 ) illustrates a perspective view of the cutting blade assembly of the round shaft tool prior to final machining, according to embodiments of the present invention.
FIG. 6 (on Sheet 1 ) illustrates a perspective exploded view of the cutting blade assembly of the round shaft tool, according to embodiments of the present invention.
FIG. 6A (on Sheet 2 ) illustrates a longitudinal centerline cross section view of the oblong beam shaft of the tool of FIGS. 1 and 6 B- 6 C, taken along line BB-BB of FIG. 6C , according to embodiments of the present invention.
FIG. 6B (on Sheet 2 ) illustrates an end view from the proximal end of the oblong beam shaft of the tool of FIGS. 1 and 6A , according to embodiments of the present invention.
FIG. 6C (on Sheet 2 ) illustrates an isometric view of the short oblong beam shaft with the gasket and the round loose tenon installed, according to embodiments of the present invention.
FIG. 6D (on Sheet 2 ) illustrates a longitudinal centerline cross-section view of the oblong beam shaft of FIGS. 6A-6C with the gasket and the round loose tenon installed, according to embodiments of the present invention.
FIG. 7 (on Sheet 1 ) illustrates a side view of the finished blade bolster, according to embodiments of the present invention.
FIG. 7A (on Sheet 1 ) illustrates a longitudinal centerline cross-section view of the finished blade bolster of FIG. 7 taken along line FF-FF of FIG. 7 , according to embodiments of the present invention.
FIG. 7B (on Sheet 1 ) illustrates a longitudinal perspective centerline cross-section view of the finished blade bolster, according to embodiments of the present invention.
FIG. 7C (on Sheet 1 ) illustrates a perspective view of the finished blade bolster of FIG. 7 , according to embodiments of the present invention.
FIG. 7D (on Sheet 1 ) illustrates an alternative perspective view of the finished blade bolster of FIG. 7 , according to embodiments of the present invention.
FIG. 7E (on Sheet 1 ) illustrates a side elevation view of a distal end of the finished blade bolster of FIG. 7 , according to embodiments of the present invention.
FIG. 7F (on Sheet 1 ) illustrates a side elevation view of a proximal end of the finished blade bolster of FIG. 7 , according to embodiments of the present invention.
FIG. 7G (on Sheet 4 ) illustrates an end view of the bolster as seen from the distal end of an assembled handle with the bolster installed, according to embodiments of the present invention.
FIG. 8 (on Sheet 1 ) illustrates a cross sectional view of the lobe design of the bolster at its perimeter, according to embodiments of the present invention.
FIG. 9A (on Sheet 2 ) illustrates a longitudinal centerline cross-section view of the round shaft taken along line CC-CC of FIG. 9D , showing the relationship of the holes that may be gun drilled from each end, according to embodiments of the present invention.
FIG. 9B (on Sheet 2 ) illustrates a proximal end view of the round shaft illustrating the optional drilled hole, according to embodiments of the present invention.
FIG. 9C (on Sheet 2 ) illustrates a distal end view of the round shaft illustrating the drilled hole for the cutting edge insert, according to embodiments of the present invention.
FIG. 9D (on Sheet 2 ) illustrates a perspective view of the continuous style blade after partial assembly, according to embodiments of the present invention.
FIG. 9E (on Sheet 2 ) illustrates a longitudinal centerline exploded cross-section view of the round shaft style blade shown in FIG. 9D , according to embodiments of the present invention.
FIG. 10 (on Sheet 6 ) illustrates various types of flute shapes commonly used in woodturning as seen in isometric perspective and transverse cross-section, any of which may be used for the shape of the cutting edge insert, according to embodiments of the present invention.
FIG. 11 (on Sheet 6 ) illustrates various shapes for the flute inserts to accommodate the various flute shapes of FIG. 10 as seen in isometric perspective and transverse cross-section, according to embodiments of the present invention.
FIG. 11A (on Sheet 6 ) illustrates various flute inserts shown in FIG. 11 after they are split and beveled and are ready for assembly, according to embodiments of the present invention.
FIG. 12 (on Sheet 6 ) illustrates the isometric perspective and transverse cross-section views of the flute inserts of FIG. 11 installed within the flute shapes of FIG. 10 , according to embodiments of the present invention.
FIG. 13 (on Sheet 6 ) illustrates the longitudinal cross-section centerline view of the tool design that incorporates a replaceable cutting edge at the in-process stage where it is partially assembled, according to embodiments of the present invention.
FIG. 13A (on Sheet 6 ) illustrates an end view from the distal end of the tool design that incorporates a replaceable cutting edge at the in-process stage where it is partially assembled, according to embodiments of the present invention.
FIG. 13B (on Sheet 7 ) illustrates the longitudinal cross-section centerline view of the tool design that incorporates a replaceable cutting edge at the in-process stage where the blade is fully assembled but without shot filling and with some machining yet to be done, according to embodiments of the present invention.
FIG. 13C (on Sheet 7 ) illustrates an end view from the distal end of the tool of FIG. 13B , according to embodiments of the present invention.
FIG. 13D (on Sheet 7 ) illustrates the longitudinal cross-section centerline view of the tool of FIG. 13B at the in-process stage where the blade is fully assembled and with the flute opened after the last machining has been done, according to embodiments of the present invention.
FIG. 13E (on Sheet 7 ) illustrates an end view from the distal end of the tool of FIG. 13D , according to embodiments of the present invention.
FIG. 14 (on Sheet 6 ) illustrates the longitudinal cross-section centerline view of the tool design that incorporates a round shaft at the in-process stage where it is partially assembled, according to embodiments of the present invention.
FIG. 14A (on Sheet 6 ) illustrates an end view from the distal end of the tool design that incorporates a round shaft at the in-process stage where it is partially assembled, according to embodiments of the present invention.
FIG. 14B (on Sheet 7 ) illustrates the longitudinal cross-section centerline view of the tool design that incorporates a round shaft at the in-process stage where the blade is fully assembled but without shot filling and with some machining yet to be done, according to embodiments of the present invention.
FIG. 14C (on Sheet 7 ) illustrates an end view from the distal end of the tool of FIG. 14B , according to embodiments of the present invention.
FIG. 14D (on Sheet 7 ) illustrates the longitudinal cross-section centerline view of the tool design that incorporates a round shaft at the in-process stage where the blade is fully assembled and with the flute opened after the last machining has been done, according to embodiments of the present invention.
FIG. 14E (on Sheet 7 ) illustrates an end view from the distal end of the tool of FIG. 14D , according to embodiments of the present invention.
FIG. 15 (on Sheet 4 ) illustrates an isometric perspective view of the handle distal end insert, according to embodiments of the present invention.
FIG. 15A (on Sheet 4 ) illustrates a side view of the handle distal end insert along with the threaded bolster locator, according to embodiments of the present invention.
FIG. 15B (on Sheet 4 ) illustrates an isometric perspective view of the handle distal end insert, according to embodiments of the present invention.
FIG. 15C (on Sheet 4 ) illustrates the longitudinal cross-section centerline view of the handle distal end insert taken along line DD-DD of FIG. 15 , with the threaded bolster locator installed, according to embodiments of the present invention.
FIG. 15D (on Sheet 4 ) illustrates an end view of the handle distal end insert from the distal end, according to embodiments of the present invention.
FIG. 15E (on Sheet 4 ) illustrates an end view of the extrusion from which the handle distal end insert is made, according to embodiments of the present invention.
FIG. 16 (on Sheet 4 ) illustrates an isometric perspective view of the handle threaded bolster locator 11 , according to embodiments of the present invention.
FIG. 17 (on Sheet 4 ) illustrates a longitudinal cross-section centerline view of the distal end of the handle assembly, according to embodiments of the present invention.
FIG. 17A (on Sheet 4 ) illustrates an end view of the handle outside sleeve, according to embodiments of the present invention.
FIG. 17B (on Sheet 4 ) illustrates an exploded isometric perspective view of the distal end of the handle assembly along with the blade bolster, according to embodiments of the present invention.
FIG. 17C (on Sheet 4 ) illustrates an exploded isometric perspective view of the distal end of the handle assembly along with the blade assembly, according to embodiments of the present invention.
FIG. 17D (on Sheet 4 ) illustrates an isometric perspective view of the distal end of the handle assembly, according to embodiments of the present invention.
FIG. 17E (on Sheet 4 ) illustrates an end view of the handle outside sleeve showing the shape details of the surface lobes, according to embodiments of the present invention.
FIG. 17F (on Sheet 4 ) illustrates a transverse cross section view of the handle assembly showing the presence of the outside sleeve around the handle extruded insert, according to embodiments of the present invention.
FIG. 18 (on Sheet 4 ) illustrates a transverse cross section view of the handle extruded insert, according to embodiments of the present invention.
FIG. 19 (on Sheet 5 ) illustrates the foreshortened longitudinal cross-section centerline view of the handle assembly with the blade bolster installed, according to embodiments of the present invention.
FIG. 20 (on Sheet 5 ) illustrates an end view of the outer perimeter of the handle proximal end cap, according to embodiments of the present invention.
FIG. 21 (on Sheet 5 ) illustrates an isometric perspective view of a complete handle assembly, according to embodiments of the present invention.
FIG. 22 (on Sheet 5 ) illustrates an isometric perspective view of a complete tool, with the blade assembly inserted into the handle assembly, according to embodiments of the present invention.
FIG. 23 (on Sheet 5 ) illustrates a transverse cross section view of the handle taken along line NN-NN of FIG. 21 , illustrating the inclusion of metallic shot used for damping, according to embodiments of the present invention.
FIG. 24 (on Sheet 5 ) illustrates an exploded isometric perspective view of the handle assembly, according to embodiments of the present invention.
FIG. 25 (on Sheet 5 ) illustrates a longitudinal cutaway view of the handle taken along line EE-EE of FIG. 24 , showing the arrangement of the handle insert and the handle outside sleeve, according to embodiments of the present invention.
FIG. 26 (on Sheet 5 ) illustrates an isometric perspective view of the handle insert, according to embodiments of the present invention.
FIG. 27 (on Sheet 5 ) illustrates an exploded isometric perspective view of the proximal end of the handle assembly, according to embodiments of the present invention.
While the invention is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
LIST OF REFERENCES
The following reference numbers are used herein to refer to the following features:
1 Edge Insert 1 a Edge Insert After External Machining and Drilling 1 b Edge Insert After Flute Grinding 1 c Edge Insert After Flute Grinding 1 d Edge Insert After Flute Grinding 1 e Edge Insert After Flute Grinding 1 f Edge Insert assembly cross grind 1 g Edge Insert Assembly Finish Ground Distal End 2 Flute Insert 2 a Flute Inserts—ready for Shape Grinding 2 b Flute Insert Alternate Shape 2 c Flute Insert Alternate Shape 2 d Flute Insert Alternate Shape 2 e Flute Insert Alternate Shape 3 Shaft Tip for Edge Insert 3 a Hole—Standard Tool Distal End 4 Gasket, Support to Shank 5 Tenon, Support to Shank 5 a Tenon Hole 6 Shaft—Hollow or Solid 7 Bolster 7 a Bolster Lobe 7 b Bolster Proximal End Hole c Bolster Distal End Hole 7 d Bolster Taper Lock 7 e Bolster Taper to Shaft 8 Shot, Metallic 8 a Void, for shot 9 Shaft for Edge Insert—Hollow or Solid 10 Handle Distal End Insert 10 a Taper In Handle Distal End Cap 10 b Handle Extrusion 11 Bolster Locator Threaded—Handle Distal End 12 Handle Outside Sleeve 12 a Handle Internal Voids 12 b Lobe on Handle 13 Handle Extruded Insert 14 Handle Proximal End Insert 15 Handle Proximal End Cap 15 a Lobe on Handle End Cap
DETAILED DESCRIPTION
Replaceable Cutting Edge Tools
FIG. 1 illustrates a bowl gouge variant of a fluted tool incorporating metallic shot damping and providing a replaceable cutting edge insert assembly. For the woodturner, the tool consists of a handle and a cutting blade assembly which are reversibly or removably joined together. The exploded view of the tool illustrating all of the various blade components is shown in FIG. 3 .
The cutting edge insert 1 may be, but is not limited to, high vanadium tool steel commonly known as 10V or 15V. The initial cutting edge insert workpiece 1 , illustrated as 1 a in FIG. 10 on Sheet 6 , starts as a round bar that has been cut to the appropriate length. The flute shape is machined into this piece by various means, including but not limited to milling, electrical discharge machining, and/or grinding. Variants of the flute shape are, but are not limited to, those shown as 1 b , 1 c , 1 d , 1 e in FIG. 10 on Sheet 6 . This piece can be heat treated to optimal woodturning properties before or after machining depending on the choices of material and assembly method.
The flute insert 2 is made of, but is not limited to, 400-series stainless steel which starts as a round bar that has been cut to the appropriate length. The initial flute insert workpiece 2 , illustrated as 2 a in FIG. 11 on P. 1 F, starts as a round bar that has been cut to the appropriate length. The obverse flute shape is machined into this piece by various means, including but not limited to milling, electrical discharge machining, extrusion, and/or grinding. Variants of the obverse flute shape are, but are not limited to, those shown as 2 b , 2 c , 2 d , 2 e in FIG. 11 on P. 1 F. This piece can be heat treated to optimal properties before or after machining depending on the choices of material and assembly method.
The double length pieces shown in FIG. 11 on Sheet 6 may be machined into two separate inserts complete with chip deflecting bevel, as seen in FIG. 11A on Sheet 6 , and may then be assembled into the oblong beam shaft tip 3 at the same time and with the same method as that for the cutting edge insert 1 , according to embodiments of the present invention.
The oblong beam shaft tip 3 may be made of 400-series stainless steel which starts as a round bar that has been cut to the appropriate length, according to embodiments of the present invention. It may be machined by grinding into an oblong cross-sectional shape as seen in FIGS. 3B , 3 C, 6 B, and 13 A, and may then be gundrilled from the distal end to a size so as to permit the cutting edge insert 1 to be inserted into the drilled hole 3 a with a sliding fit, as shown in FIGS. 3A and 3C . It may also be gun drilled from the proximal end to a size which will allow the insertion of the round loose tenon 5 into the drilled hole 5 a . Clearance between the cutting edge insert 1 and the oblong beam shaft tip 3 and the round loose tenon 5 allow for fitting as well as accommodating the chosen lamination joining method, whether it be brazing or a polymeric adhesive or other method. In the case of a polymeric adhesive, the cutting edge insert 1 and the oblong beam shaft tip 3 may be heat treated before assembly. If brazing is used, the joining and heat treating can occur during the same hardening heat treat cycle, according to embodiments of the present invention.
As illustrated in FIG. 3C the fluted cutting edge insert opens toward a first direction, and a height of the shaft tip along the first direction is larger than a width of the shaft tip along a second direction perpendicular to the first direction. As such, the cross-sectional shape of the shaft tip (which may also be the cross-sectional shape of the rest of the shaft) includes a substantially beam-shaped cross-section, which fortifies the shaft along the direction in which the fluted cutting tool opens, thereby providing improved durability and vibration reduction, according to embodiments of the present invention.
The final steps in finishing the cutting edge assembly include grinding across the distal portion of the oblong beam shaft tip 3 to open the flute of the tool. This transforms this area of the tool from what is shown in FIG. 2 on Sheet 1 and FIG. 13 on Sheet 6 to that shown in FIGS. 1 , 1 A, and 1 B. The last step is sharpening, the grinding of the distal end of the tool, thus creating a suitable cutting edge on the tool.
The gasket 4 between the oblong beam shaft tip 3 and the oblong beam shaft 6 may be made of an aluminum bronze material. Purchased as sheet material, it is machined and formed in such a way that it can be mounted onto the round loose tenon 5 and has the same outside shape as the oblong beam shaft parts 3 and 6 , according to embodiments of the present invention.
The oblong beam shaft to cutting edge assembly round loose tenon 5 may be made of 400-series stainless steel, according to embodiments of the present invention. It provides alignment and structural strength for the assembly and joining of the oblong beam shaft tip 3 , the oblong beam shaft gasket 4 , and the oblong beam shaft 6 , according to embodiments of the present invention. It starts as a round bar that has been cut to the appropriate length. It may be machined by grinding into a precise diameter and is shown in FIGS. 1B , 3 , 6 D, and 6 E, according to embodiments of the present invention.
The oblong beam shaft 6 is made of the same material and has similar processing as the oblong beam shaft tip 3 described above, according to embodiments of the present invention. The distal end of shaft 6 is machined to accommodate the installation of the gasket 4 and the round loose tenon 5 . The proximal end is machined to a shape and size to allow its installation into and attachment to the bolster 7 .
The bolster 7 may be made of pearlitic flake graphite cast iron. It starts as a round bar casting that has been cut to the appropriate length. The internal and external shapes and features are machined into this piece by various means, including but not limited to lathe turning, traditional grinding, profile grinding, and/or creep feed grinding. FIGS. 7 , 7 A, 7 B, 7 C, 7 D, 7 E, and 7 F contain illustrations and design details of this part. If the bolster 7 is made of cast iron, after all machining is completed it may be given a corrosion inhibiting surface treatment such as, for example, plasma nitriding.
The metallic shot 8 used for filling the oblong beam shaft 6 can be any of many metallic particulate materials. According to some embodiments of the present invention, steel shot is a cost effective metallic filling. Metallic shot 8 may also be referred to as metallic spherules, according to embodiments of the present invention.
The following describes an exemplary assembly sequence, according to embodiments of the present invention.
The distal end of the tool blade is made up of the cutting edge insert 1 , the flute insert 2 , and the oblong beam shaft tip 3 . After each is machined, they are joined together into the assembly shown in FIG. 3D . This may be done by brazing, according to embodiments of the present invention. If joined by brazing, the assembly can be heat treated afterwards for property optimization. If assembled by some other joinery method, the components may be heat treated before assembly.
The proximal end of the tool blade is made up of the gasket 4 , the round loose tenon 5 , the oblong beam shaft 6 , the bolster 7 , and the metallic shot 8 , according to embodiments of the present invention. After each is machined, they are joined together. If brazing is used, the assembly can be heat treated after brazing. If assembled by some other joinery method, the components may be heat treated before assembly.
At this point the proximal end of the partially completed blade assembly may be filled with metallic shot 8 and joined to the bolster 7 . As described above, this assembly method can utilize polymeric adhesives or brazing, for example. If the latter, this can be done during or after the tempering heat treating process. The proximal end of the tool oblong beam shaft 6 of the cutting blade assembly is inserted into the distal hole 7 c of bolster 7 and is then affixed to the bolster 7 . The completed blade assembly perspective view is shown in FIG. 1 a . The completed blade assembly longitudinal centerline cross-section view is shown in FIG. 1 b . The completed blade assembly end view looking from the distal end is shown in FIG. 1 c.
According to embodiments of the present invention, the cutting edge assembly is replaceable. This replaceability of the cutting edge assembly may be accomplished by including the gasket 4 and the round loose tenon 5 between the oblong beam shaft tip assembly and the oblong beam shaft as well as adding the corresponding machining and processing to accommodate these components. The dimensional relationship of these components is illustrated in FIGS. 3D , 3 E, 6 C, and 6 D. The assembly and joining of the oblong beam shaft tip 3 , the oblong beam shaft tip to oblong beam shaft gasket 4 , the oblong beam shaft to cutting edge round loose tenon 5 , and the oblong beam shaft 6 is reversible in such cases. If the assembly joining uses polymeric adhesives, the oblong beam shaft 6 may be heat treated prior to assembly. If the assembly joining is by brazing, this can be done as part of the same hardening heat treat cycle used to join the cutting edge insert 1 , the flute insert 2 , and the oblong beam shaft tip 3 , according to embodiments of the present invention.
A polymeric adhesive such as, but not limited to, Loctite 680 for the joint of the round loose tenon 5 and the gasket 4 to the oblong beam shaft tip 3 in and around hole 5 A provides the bonding method for the transverse joining of the distal and proximal oblong beam shaft assemblies shown in FIGS. 3D and 6C , respectively, according to embodiments of the present invention. This adhesive may deteriorate when heated to 250° C. Therefore, simply putting the completed cutting blade in a kitchen oven at this temperature will allow the user to separate the two shafts to allow replacing the distal end assembly.
The bolster 7 includes a conical taper portion 7 d which serves to support the blade while accurately and firmly locating the tool into the handle (see FIG. 8 on P. 1 A), according to embodiments of the present invention. The cutting blade assembly is secured to the handle by tension created by a drawbolt style attachment, created by engaging a threaded bolster locator 11 which is secured inside the handle and which is engaged into the internal threaded proximal end bore 7 B of the bolster 7 , according to embodiments of the present invention.
FIG. 22 on P. 1 E illustrates the handle as assembled. The exploded view of the handle illustrating the various components is shown in FIG. 8 , according to embodiments of the present invention. Details of the handles and the entire tool assembly are described below.
Round Shaft Tools
FIG. 4 on P. 1 A illustrates the tool blade of a bowl gouge variant of a fluted tool that does not include a replaceable cutting edge insert assembly, according to embodiments of the present invention. For the woodturner, the tool consists of a handle and a cutting blade assembly which are reversibly joined together. The exploded view of the tool illustrating the various blade components is shown in FIG. 6 , according to embodiments of the present invention.
The cutting edge insert 1 and the flute insert 2 may be the same as or similar to those described, above. For this round shaft style of tool, the oblong beam shaft assemblies may be replaced by a single round shaft 9 .
The round shaft 9 may be made of, for example, 400-series stainless steel which starts as a round bar that has been cut to the appropriate length, according to embodiments of the present invention. It may then be gun drilled from the distal end as shown in FIG. 9A such that hole 3 a is of a size which will allow the cutting edge insert 1 to be inserted into the drilled hole with a sliding fit. Clearances between the cutting edge insert 1 and the round shaft 9 allow for fitting as well as accommodating the chosen lamination joining method, for example brazing or a polymeric adhesive, according to embodiments of the present invention. In the case of polymeric adhesive, the cutting edge insert 1 and the round shaft 9 may be heat treated before assembly. If brazing is used, the joining and heat treating may occur during the same hardening heat treat cycle.
The round shaft tool version can be made with or without the addition of metallic shot added to the inside of the tool shaft, according to embodiments of the present invention. If metallic shot damping is included, then the proximal end of the tool is gun drilled to provide a void 8 a in the shaft that accommodates the shot, as shown in FIG. 9A on Sheet 2 , according to embodiments of the present invention.
Whether or not metallic shot is added to the inside of the tool shaft, the proximal end of the partially completed blade assembly may then be joined to the bolster 7 . As previously described, this assembly method can utilize various joining procedures, including but not limited to polymeric adhesives and/or brazing. If brazing is used, this can be done during or after the tempering heat treating process.
The final steps in finishing the cutting edge assembly include grinding across the distal portion of the shaft 9 to open the flute of the tool, according to embodiments of the present invention. This transforms this area of the tool from what is shown in FIG. 5 on Sheet 1 and FIG. 14 on Sheet 6 to that shown in FIGS. 4 , 4 A, and 4 B. A final step includes sharpening, for example by grinding of the distal end of the tool, thus creating a suitable cutting edge on the tool, according to embodiments of the present invention.
The completed blade assembly perspective view is shown in FIG. 4A on Sheet 3 for the shot filled version. The completed blade assembly longitudinal centerline cross-section view for the shot filled version is shown in FIG. 4B . The completed blade assembly distal end view is shown in FIG. 4C . For the version without any shot, the proximal end of the round shaft 9 is solid, as depicted in FIG. 5 on Sheet 1 , according to embodiments of the present invention.
The finished blade assembly shown in FIG. 4 may then be attached to the handle shown in FIG. 21 in the same fashion as the tool shown in FIG. 22 .
Handles
FIG. 21 on Sheet 5 illustrates the handle as assembled. The exploded view of the handle illustrating various components according to embodiments of the present invention is shown in FIGS. 24 , 25 , and 26 .
The handle outside sleeve 12 may be formed from a pultruded thick-walled tube made of a resin bonded composite of fiberglass and carbon and aramid fibers, according to embodiments of the present invention. Outside sleeve 12 may be produced in long lengths and subsequently cut to desired lengths. The shape and size of one example of the sleeve 12 is illustrated in FIG. 17E on Sheet 4 . Both the shape and the size have been determined by ergonomic studies to be a best fit for the spectrum of woodturners, according to embodiments of the present invention.
The handle insert 13 is may be formed of an aluminum extrusion, sized to be a sliding fit within the sleeve 12 , according to embodiments of the present invention. Insert 13 may be produced in longer lengths and subsequently cut to desired lengths. The shape and size of one example of a handle insert 13 is illustrated in FIG. 18 on P. 1 D.
The handle distal end insert 10 may be formed of an aluminum extrusion, sized to be a profile match with the handle outside sleeve 12 , according to embodiments of the present invention. Insert 10 may be produced in longer lengths and subsequently cut to desired lengths. It may then be machined into the configurations seen in the side view in FIG. 15A , the distal end view in FIG. 15D , and the isometric perspective views of FIG. 15 and FIG. 15B and the isometric longitudinal centerline cross section view of FIG. 15C , according to embodiments of the present invention.
The distal end insert 10 includes an internal conical taper portion that matches the taper shown as 7 d on the tool bolster 7 , according to embodiments of the present invention. According to embodiments of the present invention, this aspect of the handle assembly provides for engagement of the tool blade assembly to the handle. The distal end insert 10 may be adhered, glued, or otherwise engaged with the handle outside sleeve 12 , according to embodiments of the present invention.
The handle threaded bolster locator 11 may be formed of 400 series stainless steel, which may be machined after appropriately sized bar stock is cut to size, according to embodiments of the present invention. A finished bolster locator 11 is illustrated in FIG. 16 , according to embodiments of the present invention. After machining, the bolster locator 11 may be installed into the proximal end of the handle distal end insert 10 as illustrated in FIGS. 15C and 17B . For example, the bolster locator 11 may be adhered, glued, formed integrally, or otherwise engaged with distal end insert 10 , according to embodiments of the present invention.
The handle proximal end insert 14 may be made in the same way and from the same material as that used for the distal end insert 10 , according to embodiments of the present invention. According to embodiments of the present invention, handle proximal end insert 14 provides an interface for the insertion and securement of the handle end cap 15 . A finished end insert 14 is illustrated in the exploded assembly views in FIGS. 24 and 27 . After machining, end insert 14 may be installed into the proximal end of the handle as illustrated in FIGS. 19 and 21 .
The handle end cap 15 may be made in the same way and from the same material as that used for the end inserts 10 and 14 , according to embodiments of the present invention. A finished end cap 15 is illustrated in the exploded assembly views in FIGS. 24 and 27 . After machining, end cap 15 may be installed into the proximal end of the handle proximal end insert 14 as illustrated in FIGS. 19 and 21 .
According to some embodiments of the present invention, the assembly of the handle occurs in essentially five steps:
1. inserting the distal end cap assembly (pieces 10 and 11 ) and securing it with an appropriate adhesive;
2. installing the insert 13 and securing it with an appropriate adhesive up against the inside end of the distal end cap 10 ;
3. inserting the proximal end cap 14 and securing it with an appropriate adhesive;
4. selectively and optionally filling the chosen compartments of the insert 13 with metallic shot 8 ; and
5. finally, closing the proximal end of the handle by installing the end cap 15 in the threaded portion of the end cap 14 .
According to embodiments of the present invention, the material out of which the edge insert 1 is made is more wear-resistant than the substrate metal (e.g. the shaft tip) into which it is inserted (e.g. the metal of the shaft tip 3 ). According to some embodiments of the present invention, the edge insert 1 is made with a ten to fifteen percent vanadium tool steel; according to other embodiments, other high alloy tool steels are used, for example high speed steels which contain both vanadium and tungsten to increase wear resistance. High speed steel which contains other elements such as cobalt to allow the steel to work at elevated temperatures may be used. According to embodiments of the present invention, pre-shaping the edge insert 1 and then making a reserve shape to add strength at the joint and not to expose the joint outside of the substrate, as well as deflect the shavings, permits any wear-resistant material to be used for the edge insert 1 to produce a cutting edge. Other materials which may be used for the edge insert 1 include high alloy tool steel, high speed steel, tungsten carbide, and/or ceramics such as zirconia and the like.
According to embodiments of the present invention, the substrate (e.g. the shaft tip 3 ) is a 400 series stainless steel, which may be brazed and then heat treated on the same cycle as the tool steels and high speed steels and still maintain the structural qualities and hardness required for the substrate. Other less expensive tool steels which may not have the corrosion resistance of stainless steel, but which would otherwise function in a similar manner and may be suitable for use as the substrate material.
The flute insert 2 may be made with almost any type of metal; according to some embodiments of the present invention, the flute insert 2 is made of the same kind of material as the substrate (e.g. the shaft tip 3 ).
Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof. | A woodturning tool according to embodiments of the present invention includes a shaft with a shaft tip, wherein the shaft tip is made of a first metal, and a cutting edge insert, at least a portion of an outer surface of the cutting edge insert rigidly joined to an inner surface of the shaft tip, the cutting edge insert formed of a second metal, the cutting edge insert being fluted and sharpened to form a cutting edge for woodturning, wherein the second metal is different from the first metal, and wherein the second metal is more wear-resistant than the first metal. | 1 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method of recovering cells from stool.
[0003] 2. Background Art
[0004] In Europe and the United Sates, colorectal cancer is a leading cause of cancer deaths. In Japan too, the number of patients of colorectal cancer is increasing sharply in recent years. This is believed due to the more Westernized, meat-oriented diet adopted by the Japanese. About 60 thousand people in Japan are diagnosed with colorectal cancer every year. On an organ-by-organ basis, the number of deaths from colorectal cancer is third highest, following stomach and lung cancer, and the number is expected to increase. However, colorectal cancer is known to be almost 100% curable by operation if detected early. Thus, colorectal cancer is included in an early cancer screening scheme, and many examination methods have been developed.
[0005] Examples of the examination methods for the early detection of colorectal cancer include barium enema and colonoscopy. In an enema examination, barium is injected into the large intestine and allowed to attach to the mucous membrane surface of the intestine, so that the surface irregularities can be examined by X-ray. The colonoscopy involves the direct observation of the inside of the large intestine by an endoscope. These methods have high sensitivity and specificity to the detection of colorectal cancer. In addition, the colonoscopy has the advantage that early cancer or precancerous polyps can be removed. However, these examination methods put a large burden on the patients and are costly. Particularly, the colonoscopy requires skills in operation and is associated with the risk of complications such as bleeding or perforation. Accordingly, they are not suitable for screening the general public with no subjective symptoms for colorectal cancer.
[0006] As a method for the primary screening of the general public for colorectal cancer, a fecal occult blood test is widely used. In the fecal occult blood test, the presence or absence of bleeding in the bowel is detected by examining the presence of hemoglobin contained in the stool, in order to indirectly predict the development of colorectal cancer.
[0007] The fecal occult blood test can be roughly divided into two types, namely a chemical examination method and an immunological examination method. The chemical fecal occult blood test takes advantage of the peroxidase activity of hemoglobin, and it utilizes the reaction in which guaiac contained in a filter paper is turned into a blue-green oxide due to the active oxygen produced upon breakdown of hydrogen peroxide that is added as a matrix. Commercially available filter papers for such an examination include Hemoccult II filter paper (Fujisawa Pharmaceutical Co., Ltd.) and Shionogi B filter paper (Shionogi & Co., Ltd.).
[0008] The immunological fecal occult blood test utilizes the specific binding of antihuman hemoglobin antibody to human hemoglobin. The method is well on its way to becoming the dominant fecal occult blood test method due to its high specificity. Examples include a reversed-passive hemagglutination method (Immudia Hem-Sp, Fujirebio Inc.), a magnetic-particle agglutination and gradient method (Magstream Hem-Sp, Fujirebio Inc.), and a latex agglutination method (Immunoccult, Chugai Pharmaceutical Co., Ltd.).
[0009] Though the fecal occult blood test is widely used for the screening of colorectal cancer, some people are voicing suspicion over the efficacy of the test. A positive result in a chemical fecal occult blood test using the Hemoccult II requires 20 mg per day of bleeding in the large intestine. However, in an actual colorectal cancer patient, the amount of bleeding is thought to be 10 mg or less. As a result, the sensitivity of the fecal occult blood test is approximately 26%, and there have been reports that only about one quarter of the actual colorectal cancer patients can be detected and the remaining three quarters are overlooked (Jama, Vol. 269, 1262-7, 1993). Further, only 8.3% of all the positives actually had colorectal cancer and many false positives were included.
[0010] Thus, there is a need for the development of a new primary screening test method with better accuracy. As a possible candidate for that purpose, a testing method utilizing cancer cells shed onto the stool is gaining attention. Compared with the fecal occult blood test that detects the bleeding in the bowel which occurs indirectly in association with a colorectal cancer, the method of the present invention directly examines cancer cells and can therefore provide a more reliable testing method.
[0011] As a method of examining cancer cells in the stool, JP Patent Publication (Kohyo) No. 2002-515973 A (WO97/28450), for example, describes a method for genetic diagnosis utilizing nucleic acids directly extracted from stool. Concrete examples of the genetic mutation detecting method include the sequence method, the PCR-RFLP (polymerase chain reaction-restriction enzyme fragment length polymorphism) method, the SSCP (single-stranded conformational polymorphism) method, and the PTT (protein truncation test) method. Apart from the detection of genetic mutations, diagnostic methods that utilize the instability of a microsatellite (MSI, microsatellite instability) or the appearance of a long DNA (L-DNA) as indicators are known.
[0012] As the genes that can be examined for genetic mutations, K-ras, APC, P53 and DCC, for example, are widely known. Searches actively continue even now for genes that can be new objects of examination, taking advantage of different expression levels and utilizing a microarray, for example. A method has also been proposed that uses the expression pattern of a splicing variant of the CD44 gene as a marker.
[0013] One problem associated with these testing methods is the fact that the nucleic acids in the stool derive from various bacteria and normal cells, and that the ratio of genes deriving from cancer cells collected from the stool is very small (about 0.05%). This poses a significant hindrance in the examination of mutations in cancerous cell-derived genes or subtle changes in expression patterns, thus making the practical application of the method difficult.
[0014] Thus, methods of collecting cancer cells directly from stool and examining them have been considered, with a view to providing a more reliable colorectal cancer diagnosis. In order to collect cancer cells from stool, two steps are important. One is the step of exfoliating cells from the stool, and the other is the step of collecting the exfoliated cells.
[0015] JP Patent Publication (Kohyo) No. 11-511982 A (1999) (WO97/09600) reports a preliminary processing method whereby the stool is cooled in the step of exfoliating cells therefrom, and then the cells existing under the surface of the stool are exfoliated. Specifically, claim 1 of the document recites the step of “cooling the stool to a temperature below its gel freezing point,” and in this method, the surface of the stool cooled and frozen is scraped and the cancer cells existing in the surface are exfoliated. Methods have also been reported that employ a device called stomacher that is capable of mildly pulverizing a solid matter, wherein the entire stool is suspended and cells are exfoliated.
[0016] In the step of recovering the exfoliated cells, a centrifugal separation method utilizing a Percoll (Int J Cancer, Vol. 52, 347-50, 1992) or a recovery method utilizing magnetic beads to which an antihuman antibody is bound (Lancet, Vol. 359, 1917-9, 2002, Apmis, Vol. 110, 239-46, 2002) have been reported. Particularly, magnetic beads to which Ber-EP4 antibody is bound that specifically binds to epithelium cells are commercially available (Dynabeads Epithelial Enrich, Dynal Biotech), and they are known to bind to colorectal cancer cell lines. In Patent Document 2 too, the Ber-EP4 binding magnetic beads are utilized for recovering cancer cells from stool.
SUMMARY OF THE INVENTION
[0017] In a large-scale colorectal cancer screening performed on the general public, a large amount of multiple specimens must be processed by an automated system. The method in which cells are directly recovered from stool and examined for colorectal cancer is excellent in reliability. However, in the existing method whereby cells are recovered from the surface of stool that is frozen by cooling, as described in JP Patent Publication (Kohyo) No. 11-511982 A (1999) (WO97/09600) (to be hereafter referred to as a cooling method), the operation is bothersome and the screening cannot be performed on a large scale.
[0018] In order to realize the automated processing of a large amount of multiple specimens, the operation must be simplified and the time of operation must be reduced. In the cooling method, there is the step of centrifugation, which takes time and does not render itself to automation and thus makes the processing of multiple specimens difficult. Further, the specimen cooling operation requires large-sized equipment and makes the stool processing operation complicated.
[0019] For the determination of colorectal cancer using the cells recovered from stool, a method employing a cytological analysis for identifying colorectal cancer is very effective. However, in the conventional cooling method, the cells are damaged by the cooling operation, thereby making it difficult to perform a cytological analysis.
[0020] Further, in the cooling method, the cells below the surface of the stool are exfoliated and recovered. In the ascending colon portion near the small intestine, the stool is in the form of muddy water, and it is believed that the most cancer cells exfoliated from the walls of the large intestine are later taken into the inner core of the stool during the process of forming a solid feces. Thus, it is likely that cancer cells deriving from the ascending colon cannot be recovered by the cooling method.
[0021] To solve the aforementioned problems, the method and apparatus for the recovery of cancer cells according to the invention are operated at room temperature.
[0022] Specifically, in contrast to the cooling method in which the surface of a cooled and frozen stool is scraped and then cancer cells existing in the surface of the stool are exfoliated, the method of recovering cells according to the invention includes the steps of, at room temperature, preparing a sample to which a buffer solution is added, causing a cancer cell in the sample from which the impurity has been removed to be adsorbed on a solid carrier, and recovering the thus adsorbed cancer cell. Thus, all of the steps for the recovery of cancer cells can be conducted without temperature control. Similarly, the apparatus for recovering cells according to the invention includes a bag for storing a sample comprising a buffer solution and stool at room temperature, and a container in which a solid carrier for the adsorption of a cell in the sample is stored. Thus, the cell recovery apparatus does not require a temperature control means. As a result, the cell recovering method and apparatus according to the invention can simplify the cell recovery operation and allow cancer cells in stool to be recovered stably and efficiently, thereby providing a high determination accuracy.
[0023] FIG. 1 shows the temperature dependency of the cell stability in stool and the antigen-antibody binding reaction rate. As shown in FIG. 1 , when the temperature is low, the cell stability in stool decreases and, particularly, in a frozen state at temperatures of 4° C. or lower, the cancer cells could be destroyed, which would make it difficult to carry out the subsequent cytological analysis. On the other hand, with regard to the antigen-antibody binding reaction rate, the antibody is deactivated as the temperature increases, thus also making it difficult to carry out the subsequent immunological operations. Thus, in accordance with the invention, a range of temperatures around room temperature, or a temperature range between 5° C. and 40° C., or preferably between 15° C. and 35° C., is adopted so as to make both the cell stability and the antigen-antibody binding reaction rate compatible with each other. All of the steps from the recovery of cancer cells to the adsorption may be conducted at room temperature.
[0024] Further, the invention provides a novel filter system capable of handling a suspension of stool as a whole. A funnel-shaped filter improves the efficiency of filtering of a stool suspension, reduces the time required for operation, and eliminates the operation of centrifugation, thereby greatly simplifying the entire operation. Further, as cells are recovered from the stool as a whole including the central portion thereof, cancer diagnosis can be conducted on the entire large intestine. On the other hand, a multi-stage filtering apparatus allows the cells to be trapped on a film and thus condensed. The film in which the cells are trapped can then be recovered, so that the invention can be adapted for an automated system.
[0025] Further, conditions for a protocol have been analyzed, including the addition of blood serum into a stool suspension, and a simplified protocol has been developed whereby all of the steps can be operated at room temperature.
[0026] In accordance with the method and apparatus of the invention for cell recovery, good, living cancer cells can be recovered from stool at room temperature, in contrast to the cooling method as disclosed in JP Patent Publication (Kohyo) No. 11-511982 A (1999) (WO97/09600), whereby the surface of a cooled and frozen stool is scraped and then cancer cells existing in the surface of the stool are exfoliated. Thus, in accordance with the invention, the recovered cells can be subjected to cytological, immunological and biochemical analyses with high accuracy. Also, the method and apparatus of the invention for recovering cells can utilize a cell deriving from early colorectal cancer or the stool as a whole as a specimen, cancer cells deriving from the ascending colon, which are difficult to detect endoscopically, can be recovered. Thus, the invention can provide a highly reliable examination method. Further, the method and apparatus of the invention have eliminated the centrifugation and cooling operations so that the operation can be simplified and performed in less time. Thus, an automated total system for colorectal cancer examination can be constructed using the method and apparatus of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 shows a graph indicating the temperature dependency of the cell stability in stool and the antigen-antibody binding reaction rate.
[0028] FIG. 2 schematically shows a standard protocol for a method of recovering colorectal cancer cell from stool.
[0029] FIG. 3 shows the shape of a funnel-shaped filter for filtering a stool suspension.
[0030] FIG. 4 shows the concept of a total system for colorectal cancer examination according to the present invention.
[0031] FIG. 5 shows the results of analysis of conditions for the cell recovery method. FIG. 5 (A) shows the relationship between the temperature at which the cells and the magnetic beads bind to one another, and the cell recovery rate. FIG. 5 (B) shows the relationship between the presence or absence of blood serum in the medium and the cell recovery rate.
[0032] FIG. 6 compares the cell recovery rate according to the conventional method and that according to the magnetic bead method of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[heading-0033] (Recovery of Cells from Stool)
[0034] FIG. 2 shows the standard protocol for the method of recovering cells from stool according to the present invention. Hereafter, the procedure of the standard protocol will be described.
[heading-0035] (Step 1 : Recovery of Specimens)
[0036] The stool used in the present invention is stool naturally voided by a human. A solid stool is used and diarrheal stool is not used. Neither is that stool used that has been voided after the subject had taken a compulsive relieving agent such as a laxative or barium for intestinal examination. There is no need for the subject to exercise any particular diet control prior to the test.
[0037] The stool for specimen is recovered on a dish- or sheet-shaped disposable container, and an appropriate amount is put into a stomacher bag. Other methods of stool recovery may be employed, such as by means of a stick-type stool recovery apparatus or a stamp-type recovery apparatus, as long as the method is capable of recovering an appropriate amount of stool. As the stomacher bag, a commercially available filterless bag is employed. A stomacher bag with a filter may be used. The stomacher herein refers to mixers in general for the pulverization of specimens contained in a bag-like container. The stomacher bag refers to a commercially available bag specifically designed for stomachers. Other substitutes may be used as long as they can be used with stomachers.
[0038] The stool recovered from the subject should preferably be used within three hours but may be used within up to approximately ten hours. The stool can be stored at room temperature during that period and there is no need to store it in a refrigerated or frozen state.
[0039] The amount of stool used is preferably in the range between about 5 g and 80 g. However, the amount may range from about 0.5 g to 200 g.
[0040] A suspension medium is put into the stomacher bag in which the stool is recovered. The medium is a Hanks solution. However, any conventional medium that is used in experiments involving cells may be used. Specific examples include PBS, PBS (−) and media for the cultivation of various cells (MEM, DMEM, RPMI).
[0041] The amount of medium added may be varied depending on the amount or state of stool. However, the amount is preferably 1 mL or more per 1 g of stool. By adding 200 mL of medium per one stomacher bag, any of the aforementioned amounts of stool may be accommodated.
[0042] Blood serum is added to the medium. The concentration of blood serum is preferably 10% but may be in the range between 0.5% and 20%. The blood serum is preferably FBS (fetal bovine serum) but may be CS (calf serum).
[0043] The stomacher bag containing the stool with medium is sealed with a sealer. Leakage of the suspension can be more completely prevented by covering the stomacher bag with another stomacher bag. The thus sealed stomacher bag is processed by a stomacher to produce a stool suspension. This step of recovering a specimen is conducted at room temperature. However, if it takes time between the recovery of specimen and filtration, the stool suspension may be stored in a cooler box, for example.
[heading-0044] (Step 2 : Filtration)
[0045] The suspension is filtered by a filter in a draft to remove residual matter. When a stomacher bag with a filter is used, the suspension is filtered by the filter in the bag and the filtered solution is recovered.
[0046] When a stomacher bag with no filter is used, a new filtering apparatus is used for filtering the suspension.
[0047] The filtering apparatus is used either with a single filter or in a multiple-stage arrangement made up of filters with various sizes. When a single filter is used, the size is preferably about 500 μm. However, the size may be in the range between 40 to 1500 μm, or preferably between 400 and 1000 μm. When the multiple-stage arrangement is used, the suspension is caused to flow from a filter with a larger size to one with a smaller size. The size of the filters for the multiple-stage filtering may be between about 40 to 2000 μm. By disposing a filter with a size of 10 μm or less in the final stage, the cells can be captured on the final filter.
[0048] The filtering apparatus may be either of a free-fall type or a suction filtering type.
[0049] FIG. 3 shows an example of the shape of filter. The funnel shape of the filter has dimensions such that the diameter of the opening is 60 mm, the diameter of the bottom is 20 mm, the height is 200 mm, and the height when the filter is inserted into a container is 170 mm, for example. The filter shown in FIG. 3 is a funnel-type three-dimensional filter having filtering sides. Preferably, a bottom-surface type filter having a filtering surface only at the bottom may be used. Further, the surface of the filter may be provided with fold-like irregularities such that the area of contact with the suspension can be increased.
[0050] The material of the filter is preferably nylon. Other materials may be used as long as they are capable of allowing a filter with a desired size or shape to be produced. Specific examples include polyester, polyethylene, and polypropylene. This filtering step is conducted at room temperature.
[heading-0051] (Step 3 : Magnetic Beads Reaction)
[0052] The cells contained in the filtered solution are recovered using a carrier having an affinity for cancer cells. The carrier is made of magnetic beads having bound to the surfaces thereof an antibody with an affinity for cancer cells. Specifically, Ber-EP4 antibody-binding magnetic beads commercially available from Dynal Biotech (Dynabeads Epithelial Enrich) are used. Besides Ber-EP4, other antibodies having an affinity for colorectal cancer cells may be used. Besides antibodies, aptamars or ligands having an affinity for colorectal cancer cells may be used.
[0053] Forty mircrolitters of magnetic beads are added per tube containing about 20 to 45 mL of dispensed filtered solution. The amount of magnetic beads may be varied between about 20 μL and 400 μL.
[0054] The filtered solution to which the magnetic beads have been added is blended using a mix rotor, such that the cells in the filtered solution are bound to the magnetic beads. The blending is preferably conducted at room temperature or in a cold room at 4° C., preferably for 10 minutes or more. This step of reacting magnetic beads is carried out at room temperature.
[heading-0055] (Step 4 : Magnetic Separation)
[0056] The tubes containing the blended filtered solution are placed on a magnetic stand and is then shook for 15 minutes, such that the magnetic beads are collected on the side of the tube. The shaking is preferably conducted for 10 minutes or more. The shaking may be conducted in any manner, such as a see-saw motion, rotation or gyration, as long as the filtered solution can be gradually blended.
[0057] After the magnetic beads have attached to the wall surface, the filtered solution is removed. After the removal of solution, the tubes are detached from the magnetic stand and washed with the aforementioned medium, and then the beads washing solution is recovered. The amount of medium is 500 μL per tube but may be varied as desired in light of the subsequent experiment. This step of magnetic separation is conducted at room temperature.
[heading-0058] (Step 5 : Magnetic Separation, Eppendorf Tube)
[0059] The washing solution is recovered into an Eppendorf tube or the like smaller than the previously used tubes. The tube containing the washing solution is immediately attached to a dedicated magnetic stand. After the magnetic beads have been collected on the side walls of the Eppendorf tube, the supernatant is removed to obtain pellets of cell-bead complexes. This step of magnetic separation and Eppendorf tube is conducted at room temperature.
[heading-0060] (Diagnosis for Colorectal Cancer)
[0061] The pellets recovered by the present standard protocol are then used as specimens for the determination of colorectal cancer. The determination of cancer is based either on cells themselves or a substance extracted from cells. When cells themselves are used, the pellets are used immediately after recovery. When an extracted substance is used, the pellets can be stored in a frozen state at −80° C.
[0062] When cells themselves are used, the cells are stained with Papanicolaou stain and then observed by a microscope for determination. If the ratio of nucleus to cytoplasm (N/C) is high and atypical cells with chromatin condensation are identified, the cells are determined to be cancerous. Other staining methods may be used as long as they are capable of identifying cancer cells. Besides conventional staining, immunostaining that utilizes a cancer-cell specific antibody may be used.
[0063] It is possible to extract DNA or RNA from cells and utilize them for cancer determination. For the extraction of DNA or RNA, nuclear acid extraction kits available from various companies can be employed. Specific examples of such kits include Dynabeads DNA DIREIC Universal from Dynal Biotech, QIAamp DNA MiniKit from Qiagen, and SepaGene from Sanko Junyaku Co., Ltd. for DNA extraction. For the extraction of RNA, ISOGEN from Nippon Gene Co., Ltd. and TRIzol Reagent from Invitrogen can be cited. The extracted nucleic acids can be utilized for the various methods mentioned in the description of the related art.
[heading-0064] (Stool Processing Total System)
[0065] The concept of a stool processing total system according to the present invention is shown in FIG. 4 . Collected specimens are suspended using a stomacher. For the filtering of the suspension, an apparatus in which single funnel-shaped filters are arranged as shown in FIG. 4 can be used. The apparatus may be replaced with a multi-stage filtering apparatus. The filtering apparatus is equipped with a suction filtering function. The filtered liquid is dispensed and agitated after the addition of beads. For the agitation, a conventional agitator may be adapted, or an apparatus suitable for the simultaneous processing of multiple specimens may be used. For magnetic separation, a conventional magnetic stand or a stand with an increased magnetic force adapted for the processing of multiple specimens may be used.
[0066] Cancer determination is made by using the recovered cell-beads complex. For the determination of cancer, a material extracted from the cells or the cells themselves are used. An automated system is constructed by adapting examination methods based on expression analysis utilizing a DNA chip or protein chip, or the identification of cancer cells utilizing flow cytometry.
EXAMPLES
[0067] Hereafter, an example of the invention will be described. The invention, however, is not limited to the example.
[heading-0068] (Recovery of Cells from Stool)
[0069] Stool voided by a colorectal cancer patient prior to operation was used as a specimen. As to the use of stool, the subject was informed of the content of the procedure prior to the experiment and a written consent was obtained.
[0070] Two hundred mL of Hanks solution (Nissui) containing 10% FBS was put into a stomacher bag containing stool (about 5 to 80 g) and the bag was then sealed. A stool suspension was then prepared by using a stomacher (200 rpm, 1 min).
[0071] In the case where a stomacher bag having a filter was used, the suspension was filtered by the filter in the bag. In the case where a stomacher bag without a filter was used, the suspension was filtered by passing it through a funnel-shaped filter set on a tubular plastic container. The filtered solution was recovered in a beaker. The filtered solution was further dispensed into five 50-mL centrifugal sedimentation tubes.
[0072] Forty μL of Ber-EP4 antibody-binding magnetic beads (Dynabeads Epithelial Enrich, Dynal Biotech) was added per centrifugal sedimentation tube, and the mixture was blended using a mix rotor (VMR-5, available from AS ONE) (at 4° C., 60 rpm, 30 min) so that the cells in the filtered solution were bound to the Ber-EP4 antibody.
[0073] After the individual centrifugal sedimentation tubes were set on a magnetic stand (Dynal MPC-1, Dynal Biotech), the stand was laid on a mild mixer (SI-36, TAITEC Corporation) horizontally. The tubes were then subjected to a seesaw motion for 15 minutes ( 60 reciprocations per min) to blend the filtered solution such that the magnetic beads were collected on the side walls of the centrifugal sedimentation tubes.
[0074] After the filtered solution was removed, the centrifugal sedimentation tubes were detached from the stand, and 500 μL of Hanks solution containing 10% FBS was added per tube to wash the beads collected on the wall surface.
[0075] The washing solution containing the beads was recovered into five Eppendorf tubes (1.5 mL each) in which 500 μL of Hanks solution containing 10% FBS had been put in advance. After a light suspension, the tubes were set on a magnetic stand (Dynal MPC-S, Dynal Biotech), and the magnetic beads were collected on the side walls of the Eppendorf tubes.
[0076] After the removal of the washing solution, the Eppendorf tubes were detached from the stand, and 1 mL of Hanks solution containing 10% FBS was added to each tube, and then the beads collected on the wall surface were washed. Similarly, the tubes were set on the magnetic stand and the magnetic beads were collected on the side walls of the Eppendorf tubes. The supernatant was then removed to obtain pellets of cell-beads complex. The recovery was conducted at room temperature.
[heading-0077] (Cytological Analysis of the Recovered Cells)
[0078] The cell-beads complex pellets in each tube recovered in Example 1 were suspended with the addition of 100 μL of YM fixing solution. The suspension was then transferred to a 50-mL centrifugal sedimentation tube. The total amount was adjusted to 25 mL by YM fixing solution, thereby obtaining a cell-containing fixing solution. The cell-containing fixing solution was then dispensed into an automatic smearing apparatus for 8 glass slides. The apparatus was further filled with the YM fixing solution and was then centrifuged at 2000 rpm for 10 minutes, thereby smearing the glass slides with the cells. After drying the slides with cold air, the cells were fixed with 95% ethanol.
[0079] The cells were then stained by the Papanicolaou staining method, which is a representative method of staining for the observation of cell morphology. The presence or absence of cancer cells were microscopically observed and determined. The results are shown in Table 1.
Dukes Cyto- No. Tumor site 1) classification diagnosis Remarks 2) 1 S C + 2 Ra B + 3 S A − Diarrhea due to Niflec 4 Rb C − Diarrhea due to Niflec 5 Rb D − Clogged filter 6 S A − Clogged filter 7 Ra C + 8 Rb A + 9 Rb A + 10 Ra A + 11 Rs A + 12 Ra A + 13 Rb A + 14 A A + 15 S C + 16 T A + 1) 5: Sigmoid colon Ra: Upper rectum Rb: Lower rectum Rs: S-shaped portion of rectum A: Ascending colon T: Transverse colon 2)Nos. 1-12: Stomacher with a filter was used. Nos. 13-16: Funnel-shaped filter was used.
[0080] Table 1 shows the cases of colorectal cancer patients who provided the specimens used in the present experiment. Cytodiagnosis (+) indicates the cases where cancer cells were collected by the method of the invention, and cytodiagnosis (−) indicates the cases where no recovery of cancer cells were confirmed by the inventive method.
[0081] In cases Nos. 3 and 4, Niflec, a laxative, had been taken by the patient prior to the passage of stool, so that the voided stool was diarrheal from which cells could not be recovered. In cases Nos. 5 and 6 too, no cells could be recovered. In these two cases, the amount of stool exceeded 100 g and, in addition, a stomacher bag with a filter was used at this point for filtering the stool suspension, resulting in a significant clogging of the filter. The reduction in the cell collection rate depending on the extent of clogging of the filter had also been anticipated in a preliminary experiment, and it was clearly shown that an excessive clogging of the filter would prevent the recovery of cells.
[0082] Thus, cells were recovered from 12 out of 16 cases (75%). Even in cases where no cell could be recovered, the reasons for the absence of recovery were obvious, as mentioned above. Thus, it was clearly shown that cells can be very efficiently recovered from colorectal cancer patients by using the magnetic beads method in accordance with the present protocol.
[0083] When the progress of cancer in the colorectal cancer patients who provided the specimens was examined, 8 out of the 12 cases from which cells were recovered (67%) were classified into early cancer of Dukes A. In addition, cells could be recovered from cases of Dukes A involving the tumor sites of upper rectum (No. 14) or transverse colon (No. 16). These results show that the method of the invention is very effective in diagnosing early cancer including those cancers developed at sites where detection by colonoscopy, for example, is difficult.
[heading-0084] (Analysis of the Conditions for the Magnetic-Beads Cell Recovery Method Using Cultured Cells)
[0085] A colorectal cancer cultured cell line (HT-29) was mixed in a suspension of stool collected from an infant, and the mixture was reacted with a Ber-EP4 antibody-binding magnetic bead. The conditions that affect the cell recovery rate in the present method were then examined. The suspension of the stool from infant was filtered by the above-described funnel-shaped filter to obtain a filtered solution. The recovery rate was calculated by measuring the number of cells that bound to the recovered beads using Nucleo Counter (from M&S TechnoSystems) and comparing it with the number of cells initially added to the suspension.
[0086] First, the temperature suitable for the binding of beads and cells was examined. Magnetic beads and cells are in many cases reacted at 4° C. This is for the purpose of lowering the damage done to the cells or preventing the phenomena in which macrophages contained in the specimen prey on the beads, for example.
[0087] Thus, a mixing reaction between a 25-mL cell-(8.4×10 5 ) stool suspension and 40 μL of beads was conducted at 4° C. and at room temperature. As a result, it was revealed that the same level of cell recovery rate can be obtained at room temperature as at 4° C. ( FIG. 5A ). This indicates that all of the cell recovery steps of the method of the invention can be conducted at room temperature, whereby individual operations can be greatly simplified as compared with the aforementioned cooling method.
[0088] Next, the need for the blood serum in the cultured solution for suspension was analyzed. Blood serum was expected to have functions for improving the efficiency of the magnetic beads method by, for example, restricting the protease activity in the solution and stabilizing the cells, or preventing the adsorption of non-specific cells.
[0089] Accordingly, 25 mL of cell-stool suspension was prepared using a Hanks solution containing 10% blood serum (FBS, fetal bovine serum) and a Hanks solution containing no blood serum, and the suspension was reacted with 40 μL of beads, in order to examine the cell recovery rate in a similar manner.
[0090] The results ( FIG. 5B ) showed that the cell recovery rate was lower in the case where no blood serum was contained, thus indicating the effectiveness of blood serum in the recovery method of the invention.
[0091] Further, the size of the mesh of the funnel-shaped filter used in the present experiment was analyzed. Nylon filters of different sizes (1000, 512, 96 and 48 μm), with the entire surface made of mesh and a shape as shown in FIG. 3 , were prepared. Cultured cells were added to a stool suspension in a similar manner, filtered by these four kinds of filters, and then reacted with beads to examine the cell recovery rate.
[0092] As a result, the recovery rate of the filter of 96 μm was about one half of that of 512 μm, and the rate for 48 μm was about one fifth of that for 512 μm. The filter of 1000 μm had approximately the same recovery rate as that of the filter of 512 μm. These results thus indicated that the size of filter should preferably be 500 or more. However, in order for the filter to function as such, the size should not exceed 1500 μm.
[heading-0093] (Comparison with the Percoll Centrifugation Method)
[0094] The cell recovery rate of the magnetic beads method was compared with that of the Percoll centrifugation method, which is a conventional method. The experiment was conducted using cultured cells in a manner similar to those described above. The Percoll centrifugation method was carried out in accordance with the method of Yamao et al. reported in Non-Patent Document 4. In the Percoll centrifugation method, Percoll solution is mixed with cells and is then centrifuged in order to separate the cells according to their densities. The results are shown in FIG. 6 . The cell recovery rate was 0.8% for the Percoll centrifugation method. The recovery rate for the magnetic beads method (in accordance with the standard cell recovery protocol was 66.7%, thus indicating the advantage of the magnetic beads method. | A method and apparatus for recovering cells from stool are provided for diagnosing colorectal cancer from stool naturally voided by multiple specimens. The method includes the steps of preparing a sample of naturally voided and collected stool, to which sample a buffer solution is added, causing cancer cells in the sample from which the impurities have been removed to be adsorbed on a solid carrier, and recovering the cancer cells thus adsorbed. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a gas permeable member, in particular a gas permeable electrode including a reaction layer carrying a complex thereon as an oxidation reduction catalyst, and a method for producing the gas permeable member.
2. Description of the Background Art
Research of a new use of a phthalocyanine and complexes thereof, hereinafter referred to as a "Pc-complex" or "Pc-complexes" in the light of the catalytic characteristics has been developed. However, principal Pc-complexes are not dissolved in an organic solvent and are stable against not only an alkali but also a dilute acid. Hence, it is difficult to find a proper method for carrying the Pc-complex on a carrier. One popular Pc-complex carrying method usually used is as follows. That is, Pc-complex powder is mixed with carbon powder and the like used as a substrate for a reactive layer of a gas permeable member or electrode to obtain a powdery mixture, and the obtained powdery mixture is placed on a gas permeable layer of a sheet form and is processed into a certain form by a hot press under conditions such as at 360° C. and 600 kg/cm 2 to obtain a gas permeable electrode.
In this case, the Pc-complex is dispersed in the whole reaction layer, and an extremely large amount of the Pc-complex to be used is required to invite a high cost. Also, in this case, since the Pc-complex is dispersed in the form of powder, the surface area of the obtained reaction layer is small.
Meanwhile, in conventional electrolytic reduction of carbon dioxide for producing carbon monoxide and an organic compound, electrolytic reduction of an aqueous solution containing a bicarbonate or the like is effected, while carbon dioxide is blown into the solution, to obtain an organic compound such as formic acid, methane, ethane or the like. In this case, a usual electrode such as a copper, cadmium or lead plate is used for an electrolytic reduction electrode (cathode), and thus the current density is small. Hence, the producing efficiency of the organic compound is low, and the productivity becomes low.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a gas permeable member, especially a gas permeable electrode, free from the aforementioned defects and disadvantages of the prior art, which is capable of improving efficiency of a reaction layer and ability of catalytic characteristics, increasing surface area of the reaction layer and reducing a used amount of Pc-complex carried on the reaction layer.
It is another object of the present invention to provide a method for producing a gas permeable member, free from the aforementioned defects and disadvantages of the prior art, which is capable of improving efficiency of a reaction layer and ability of catalytic characteristics, increasing surface area of the reaction layer and reducing a used amount of Pc-complex carried on the reaction layer.
In accordance with one aspect of the present invention, there is provided a gas permeable member, comprising a reaction layer having fine hydrophilic and hydrophobic portions and carrying a complex recrystalized from sulfuric acid, on the hydrophilic portions, and a gas permeable layer bonded to the reaction layer, having fine hydrophobic portions therein.
In accordance with another aspect of the present invention, there is provided a method for producing a gas permeable member including a reaction layer and a gas permeable layer, comprising the steps of contacting a concentrated sulfuric acid solution containing a complex having solubility in sulfuric acid and recrystallizability by water with the reaction layer, and feeding the water through the gas permeable member to crystallize the complex on the reaction layer.
In accordance with still another aspect of the present invention, there is provided an electrolytic reduction method for producing an organic compound by using a gas permeable electrode as an electrolytic reduction electrode, mounted in an electrolytic cell containing KHCO 3 solution therein, the gas permeable electrode including a reaction layer having fine hydrophilic and hydrophobic portions and carrying a metal complex on the hydrophilic portions, and a gas permeable layer bonded to the reaction layer, having fine hydrophobic portions therein, in which carbon dioxide gas is fed to the gas permeable layer to pass through the gas permeable electrode to obtain carbon dioxide and an organic compound at the electrolytic reduction electrode.
BRIEF DESCRIPTION OF THE DRAWING
These and other objects, features and advantages of the present invention will more fully appear from the following description of the preferred embodiments.
A FIGURE is a longitudinal cross section of a gas permeable electrode according to the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawing, there is shown in the FIGURE one embodiment of a gas permeable electrode according to the present invention.
In the FIGURE, the gas permeable electrode 1 comprises a reaction layer 2 and a gas permeable layer 3 bonded thereto. The gas permeable electrode 1 can be applied to an anode and/or a cathode.
In this case, the reaction layer of the gas permeable electrode may be prepared as follows. That is, 4 to 8 parts by weight of hydrophilic carbon black, 2 to 8 parts by weight of hydrophobic carbon black and 2 to 4 parts by weight of polytetrafluoroethylene (PTFE) powder are uniformly mixed with one another, and then solvent naphtha as a solvent is also uniformly mixed with the mixture. Then, the obtained mixture is processed under pressure into a certain form and is then heated at 280° C. to remove the solvent, thereby obtaining the reaction layer.
The gas permeable layer of the gas permeable electrode may be prepared by using 2 to 8 parts by weight of hydrophobic carbon black and 2 to 8 parts by weight of PTFE in the same manner as the reaction layer described above.
The average particle size of the hydrophilic and hydrophobic carbon blacks is approximately 400 to 500 Å, and the average particle size of the PTFE is approximately 0.1 to 0.5 μm.
Then, the obtained reaction layer having a thickness of approximately 0.05 to 0.2 mm and the gas permeable layer having a thickness of approximately 0.3 to 1.0 mm are bonded to each other, and the bonded two layers are processed under pressure into a predetermined shape to obtain a gas permeable electrode.
Then, the Pc-complex is carried on the reaction layer of the gas permeable electrode by using a concentrated sulfuric acid solution containing the Pc-complex in some manners, as follows. That is, it can be done by immersing the reaction layer of the gas permeable electrode with the sulfuric acid solution, by spraying the sulfuric acid solution to the reaction layer of the gas permeable electrode, or by contacting the sulfuric acid solution with the reaction layer of the gas permeable electrode under pressure or while sucking from the gas permeable layer side.
When the reaction layer of the gas permeable electrode is filled up with the concentrated sulfuric acid solution containing the Pc-complex and steam is fed to the gas permeable electrode from the gas permeable layer side, the Pc-complex is crystallized on the reaction layer. That is, when the steam is fed to the gas permeable electrode from the gas permeable layer, the steam contacts with the concentrated sulfuric acid solution to dilute the concentrated sulfuric acid solution, and hence the Pc-complex cannot dissolve as before in the dilute sulfuric acid solution, i.e., the Pc-complex cannot help crystallizing on the reaction layer of the gas permeable electrode.
As to the Pc-complexes which can be dissolved in the sulfuric acid and be recrystallized by the water so as to be carried on the reaction layer of the gas permeable electrode, phthalocyanine, diphthalocyanine, metal phthalocyanine complexes having a central metal such as lead (Pb), chromium (Cr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), platinum (Pt), palladium (Pd), manganese (Mn), tin (Sn) or vanadium (V), or the like, can be used.
When the acid is entirely removed from the gas permeable electrode, it is firstly dried at the room temperature and then is preferably heated at approximately 320° to 400° C. In this instance, the sublimation of the Pc-complex can occur at over 400° C., and the acid remaining in the gas permeable electrode after washing thereof cannot be completely decomposed at below 320° C.
In this embodiment, the amount of the Pc-complex to be carried on the reaction layer of the gas permeable electrode can be freely adjusted by controlling the concentration of the Pc-complex in the concentrated sulfuric acid solution and the amount of the steam to be supplied to the gas permeable electrode from the gas permeable layer side.
In the thus obtained gas permeable electrode according to the present invention, the Pc-complex is carried on the hydrophilic carbon black dispersed in the reaction layer, and hence the Pc-complex is carried on the gas-liquid interface in the gas permeable electrode to largely improve its efficiency and ability.
The other gas permeable members in addition to the said gas permeable electrode thus obtained can be used for a variety of applications in many fields. For instance, when a central metal of a Pc-complex is cobalt (Co) or nickel (Ni), a gas permeable electrode can be used as an oxidation reduction electrode for effecting reduction of carbon dioxide, producing hydrogen peroxide or for a sensor. When a central metal of a Pc-complex is iron (Fe), a gas permeable member having a film form can be used as a deodorant.
When the gas permeable electrode of the present invention is used for electrolytic reduction of carbon dioxide, the electrolyte solution permeates into the metal complex as the catalyst of the hydrophilic portions of the reaction layer, and the carbon dioxide actively permeates and spreads into the hydrophobic portions of the reaction layer to contact with the electrolyte solution. Thus, the reduction of the carbon dioxide is actively effected on the catalyst to obtain carbon monoxide and an organic compound with high efficiency, thereby improving the productivity. Further, a large number of metal complexes can be used, and the selectivity or the control of the obtained products can be largely improved by varying the central metal of the metal complex. Further, the current density of the obtained compound can become extremely high and the product amount of the organic compound per the electrode surface area can be extremely large as compared with those of the conventional method.
According to the present invention, for instance, when the Pc-complex carried on the gas permeable electrode includes a central metal of a transition metal such as Co, Ni or Fe, oxygen atom is taken from CO 2 adsorbed on the gas permeable electrode to produce CO, and When the Pc-complex carried on the gas permeable electrode includes a central metal of a base metal such as Zn, hydrogen is added to CO 2 adsorbed on the gas permeable electrode to produce formic acid. Also, when the Pc-complex carried on the gas permeable electrode includes a central metal such as Cu, the reduction is effected to disconnect oxygen from CO 2 adsorbed on the gas permeable electrode and to produce methane at the end.
Also, by utilizing the above described features, the gas permeable member of the present invention can be used for an ozone decomposition, an air cleaning apparatus, a deodorizer of a refrigerator, a drying machine, a dehumidifier, a humidifier and a mixture gas producing apparatus.
As described above, according to the present invention, the Pc-complex as the catalyst can be carried on only the gas-liquid interface in the reaction layer of the gas permeable member without reducing or losing the functions of the gas permeable member, and the efficiency and ability of the Pc-complex carried on the reaction layer can be largely improved. Also, the amount of the Pc-complex to be carried on the reaction layer of the gas permeable member can be largely saved and be readily adjusted. In addition to the use for the electrode, the gas permeable member of the present invention can be also used in the form of film carrying a Pc-complex thereon for a wide variety of applications such as a deodorant or the like. Hence, the present invention can contribute to development of a wide field of technology.
Examples of the present invention will now be described along with Comparative Examples, but it is not intended to restrict the present invention to the Examples.
EXAMPLE 1
7 parts by weight of hydrophilic carbon black, 3 parts by weight of hydrophobic carbon black and 4 parts by weight of PTFE powder were uniformly mixed with one another, and then solvent naphtha as a solvent was also uniformly mixed to the mixture. Then, the obtained mixture was processed under pressure into a certain form and was then heated at 280° C. to remove the solvent, thereby obtaining a reaction layer of a gas permeable electrode.
6 parts by weight of hydrophobic carbon black and 4 parts by weight of PTFE were uniformly mixed with each other, and then the solvent naphtha was also uniformly mixed to the mixture. Then, the obtained mixture was processed under pressure into a certain form and was then heated at 280° C. to remove the solvent, thereby obtaining a gas permeable layer of the gas permeable electrode.
The average particle size of the hydrophilic and hydrophobic carbon blacks was approximately 420 Å, and the average particle size of the PTFE was approximately 0.3 μm.
The obtained reaction layer having a thickness of approximately 0.1 mm and the gas permeable layer having a thickness of approximately 0.5 mm were bonded to each other, and the bonded layers were processed under pressure into a predetermined shape to obtain 6 pieces of gas permeable electrodes having a dimension of 100 mm×100 mm.
6 Pc-complexes whose central metals were Co, Ni, Fe, Pb, Zn and Cu, were dissolved into concentrated sulfuric acid solution at the concentration of 20 g/l to obtain 6 Pc-complex sulfuric acid solutions. Each Pc-complex sulfuric acid solution was contacted with the reaction layer of each gas permeable electrode, and the water solution was contacted with the gas permeable layer of the same. After leaving each gas permeable electrode as it was for 5 hours, each gas permeable electrode was taken out of the Pc-complex sulfuric acid solution and the water solution. Then, the gas permeable electrodes were washed with a washing liquid such as water and were then dried.
The amounts of the Pc-complex contained in the Pc-complex sulfuric acid solution before and after the Pc-complex carrying treatment and the amount of the Pc-complex contained in washing liquid washing the gas permeable electrode taken out of the Pc-complex sulfuric acid solution were analyzed, and then the amount of the Pc-complex carried on the gas permeable electrode was calculated from these analyzed amounts of the Pc-complex to obtain 40 to 50 mg.
Comparative Example 1
7 parts by weight of hydrophilic carbon black, 3 parts by weight of hydrophobic carbon black and 4 parts by weight of PTFE powder were uniformly mixed to obtain powdery mixture, and then the obtained powdery mixture and Pc-complex powder were mixed at a mixing ratio of 3:7 to obtain a reaction layer powdery mixture. The obtained reaction layer powdery mixture was placed on a gas permeable layer of a sheet form and was processed by a hot press at a temperature of 360° C. and a pressure of 600 kg/cm 2 to obtain a gas permeable electrode carrying the Pc-complex thereon in a conventional manner. In this case, a Pc-complex having a central metal of Co or Ni was carried on each gas permeable electrode, and the amount of each Pc-complex carried was 800 mg.
Comparative Example 2
By using the two gas permeable electrodes carrying the Pc-complex having the central metal of Co or Ni, prepared in Example 1, and the two gas permeable electrodes carrying the Pc-complex having the central metal of Co or Ni thereon, prepared in Comparative Example 1, as an anode and a gas permeable electrode carrying Pt thereon as a cathode, the anode and cathode were mounted in each electrolytic cell at a distance of 10 mm therebetween, the electrolytic cell containing 0.5M of KHCO 3 solution saturated by CO 2 . A constant-current electrolysis was effected while CO 2 gas was supplied to the rear surface of the anode at a constant flowing amount and H 2 gas was supplied to the rear surface of the cathode.
The production gas discharged from the rear surface of the anode were analyzed by using a gas chromatography to find that CO was produced with approximately 100% of current efficiency in all cases.
EXAMPLE 2
The electrolysis was effected under the same conditions as those of Comparative Example 2, except using the gas permeable electrode carrying the Pc-complex having the central metal of Cu, prepared in Example 1, as the anode, methane, CO and formic acid were produced in the production gas with respective approximately 30%, 14% and 4% of current efficiency.
EXAMPLE 3
The electrolysis was effected under the same conditions as those of Comparative Example 2, except using the gas permeable electrodes carrying the Pc-complex having the central metal of V or Mn, prepared in Example 1, as the anode, H 2 was produced in the production gas with approximately 100% of current efficiency, and a trace amount of CO and formic acid were produced therein.
According to the present invention, for instance, when the Pc-complex carried on the gas permeable member, in particular, electrode includes a central metal of a transition metal such as Co, Ni or Fe, oxygen atom is taken from CO 2 adsorbed on the gas permeable electrode to produce CO. When the Pc-complex carried on the gas permeable electrode includes a central metal of a base metal such as Zn, hydrogen is added to CO 2 adsorbed on the gas permeable electrode to produce formic acid. Also, when the Pc-complex carried on the gas permeable electrode includes a central metal such as Cu, the reduction is effected to disconnect oxygen from CO 2 adsorbed on the gas permeable electrode and to produce methane at the end.
EXAMPLE 4
Cobalt phthalocyanine, hydrophobic carbon black having an average particle size of approximately 420 Å and PTFE powder having an average particle size of approximately 0.3 μm were uniformly mixed with one another and then were processed into a reaction layer including fine hydrophilic and hydrophobic portions therein and having a dimension of 0.1 mm (thickness)×100 mm (width)×100 mm (height), and hydrophobic carbon black having an average particle size of approximately 420 Å and PTFE powder having an average particle size of approximately 0.3 μm were uniformly mixed with one another and then were processed into a gas permeable layer having a dimension of 0.4 mm (thickness)×120 mm (width)×120 mm (height). Then, the reaction layer and the gas permeable layer were bonded to each other to obtain a gas permeable electrode.
The obtained gas permeable electrode as an electrolytic reduction electrode (cathode) and a Pt net as an anode were mounted in an electrolytic cell containing 0.1 liter of 0.5M of KHCO 3 solution, and an ion-exchange membrane (Nafion 117 (trade name)) as a diaphragm for separating the electrolytic cell into cathode and anode compartments was provided in the electrolytic cell. While CO 2 gas was supplied to the rear surface of the gas permeable electrode at a flowing speed of 50 ml/min, an electrolytic reduction was carried out at an electrolytic potential of 1.4 to 1.45 V with respect to the SCE (saturated calomel electrode) and a current density of 80 mA/cm 2 for 10 minutes to obtain CO with 95 to 100% of current efficiency. In this instance, when the flowing speed of the CO 2 gas was increased, the production efficiency of CO could not be changed. At the flowing speed of 500 ml/min of the CO 2 gas, CO was produced with 100% of current efficiency. When CO was supplied to the rear surface of the gas permeable electrode at a flowing speed of 100 ml/min, only hydrogen gas was produced, and the CO was not reacted to find that the cobalt phthalocyanine has a superior selectivity.
EXAMPLE 5
Electrolytic reduction was effected in the same manner as Example 4, except using tin phthalocyanine instead of cobalt phthalocyanine, to obtain formic acid with 50 to 60% of current efficiency. When CO was supplied to the rear surface of the gas permeable electrode, no formic acid was produced. Therefore, it was found that the obtained product can be readily varied by changing the Pc-complex carried on the gas permeable electrode.
Comparative Example 3
0.5 liter of 0.5M of KHCO 3 solution was contained in an electrolytic cell, and a lead plate having a dimension of 0.1 mm (thickness)×100 mm (width)×100 mm (height) was used as an electrode in a conventional manner. While CO 2 gas was supplied into the KHCO 3 solution at a flowing speed of 200 ml/min, electrolytic reduction was carried out at an electrolytic potential of 1.4 to 1.45 V with respect to the SCE (saturated calomel electrode) and a current density of 4.8 mA/cm 2 for 60 minutes to obtain formic acid with 64.5% of current density.
Although the present invention has been described in its preferred embodiments with reference to the accompanying drawings, it is readily understood that the present invention is not restricted to the above described preferred embodiments, and various changes and modifications may be made in the present invention by those skilled in the art without departing from the spirit and scope of the present invention. | Disclosed herein is a gas permeable member, in particular a gas permeable electrode, carrying a metal complex on a reaction layer thereof. A central metal of the complex may be selected from lead, chromium, iron, cobalt, nickel, copper, zinc, platinum, palladium, manganese, tin, vanadium or the like. The selectivity of a reaction employing the gas permeable member depends on the central metal so that the gas permeable member can be employed in a wide range of applications including electrolytic reduction of carbon dioxide by suitably selecting the central metal of the complex.
The complex, for instance a Pc-complex, may be deposited from sulfuric acid by diluting the sulfuric acid by water to be uniformly dispersed in the reaction layer. | 8 |
BACKGROUND
The present disclosure relates generally to a releasable connection for a downhole assembly. More particularly, the present disclosure relates to a mechanically engaged and releasable connection that may be disposed between a tool string and a downhole tool and actuated to disconnect the downhole tool from the tool string upon application of an axial load.
To form an oil or gas well, a bottom hole assembly (BHA), including components such as a motor, steering assembly and drill bit, is coupled to an end of a drillstring and then inserted downhole, where drilling commences. When forming a substantially straight borehole, the drillstring typically includes a number of pipe joints threaded end to end. Circumstances may arise in which it is desirable to disconnect the drillstring from the BHA, for example, when the BHA becomes stuck in the borehole during drilling. At such times, the drillstring is disconnected from the BHA by applying torque to the drillstring and uncoupling a threaded connection between the drillstring and the BHA. Once disconnected from the BHA, the drillstring may be extracted from the borehole and the stuck BHA subsequently retrieved via fishing, jarring or another operation.
When forming a deviated, lateral or upwardly sloping borehole, it is not economically feasible or practical to use a drillstring made from jointed pipe. Instead, the BHA may be coupled to coiled tubing, which includes one or more lengths of continuous, unjointed tubing spooled onto reels for storage in sufficient quantities to exceed the maximum length of the borehole. Because the coiled tubing cannot be disconnected from the BHA by the application of torque to the coiled tubing, an axial disconnect is positioned in the tubing string between the BHA and the coiled tubing prior to insertion of the tubing string downhole. The axial disconnect facilitates decoupling of the coiled tubing from the BHA in the event that it becomes desirable to do so, such as when the BHA becomes stuck during drilling. To decouple the BHA from the coiled tubing, the disconnect is actuated to allow the BHA to disconnect from the coiled tubing upon application of an axial load to the coiled tubing. Once disconnected from the BHA, the tubing string may be extracted from the borehole and the stuck BHA subsequently retrieved via fishing, jarring or another operation.
A variety of conventional axial disconnects have been used to decouple a coiled tubing string from a downhole tool, such as a BHA. Some conventional disconnects include locking dogs, interlocking fingers, grapples or similar devices which are actuated, such as by application of a hydraulic pressure load, to release the tool coupled thereto. One shortcoming of these disconnects is that the locking dogs, interlocking fingers, and grapples are relatively weak components, in comparison to the other components of the disconnect. Another shortcoming is that the disconnects are usually thin-walled. Both design characteristics limit the loads which may be safely applied to the disconnects. Other conventional disconnects may be capable of handling higher loads. However, those disconnects are typically very sophisticated tools, having many working parts, each representing a potential failure point and increased manufacturing cost. These disconnects may also include expensive high strength materials, also increasing costs.
Increased downhole operating loads and costs are pushing the limits of current axial disconnects. Therefore, a stronger axial disconnect that does not resort to expensive materials is desirable. Stronger axial disconnects that also have few working parts, and thus ease manufacturing, installation, or operational complexities and related costs, would likewise be desirable.
SUMMARY
The embodiments described herein provide an apparatus for mechanically engaging and releasably coupling two tubular members, such as for disconnecting a tool from a tool string. In some embodiments, the apparatus includes a first housing member having a first throughbore and a first flowbore in communication with the first throughbore, a second housing member coupled to the first housing member, the second housing member having a second throughbore in communication with the first throughbore, and a piston member disposed within at least a portion of the first and second throughbores, the piston member having a second flowbore in fluid communication with the first flowbore and moveable from a first position to a second position, wherein, in the first position, the first and second housing members are fixed relative to each other by the piston, and wherein, in the second position, the second housing member is rotatable relative to the first housing member.
In certain embodiments an apparatus includes a first tubular member having a first set of axially disposed splines and a first set of axially offset splines, a second tubular member having a second set of axially disposed splines and a second set of axially offset splines matingly engaged with the first set of axially offset splines, and a moveable member having a third set of axially disposed splines matingly engaged with the first and second sets of axially disposed splines.
In other embodiments an apparatus includes a first tubular member, a second tubular member moveably disposed in the first tubular member, a first interlocking mechanism disposed between the first and second tubular members, and a second interlocking mechanism disposed between the first and second tubular members, the second interlocking mechanism including a moveable member, wherein the first and second interlocking mechanisms are in an opposed relationship to couple the first and second tubular members in a fixed position.
In some embodiments a method includes rotationally coupling a first tubular member into a second tubular member at a first location, aligning the first and second tubulars, translating a moveable member into the first and second tubular members to couple the first and second tubular members at a second location, and reacting the first coupling against the second coupling to resist both axial and rotational movement between the first and second tubulars. Other embodiments include displacing the moveable member to release the second coupling, rotationally disengaging the first tubular from the second tubular member, and removing the first tubular member from the second tubular member.
In certain embodiments, the axially disposed interlocking engagements are in an opposed relationship with the axially offset interlocking engagement such that the anti-rotation of the axially disposed interlocking engagements reacts with the anti-translation of the axially offset interlocking engagement to couple the disconnect such that the primary tubular members are fixed both rotationally and translationally. The axially disposed interlocking mechanism may be moved or disengaged to then remove the opposing reaction forces, and disengage or decouple the axially offset interlocking mechanism. The axially disposed and offset mechanisms may be axially displaced from each other, but interact to provide the opposing reaction forces for coupling and selective release.
The features and characteristics mentioned above, and others, provided by the various embodiments will be readily apparent to those skilled in the art upon reading the following detailed description, and by referring to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a tubing string including a tri-lock disconnect system in accordance with the principles described herein in a deviated well;
FIG. 2 is a perspective, cross-sectional view of the tri-lock disconnect system of FIG. 1 ;
FIG. 3 is a perspective view of the lower housing member of FIG. 1 in partial cross-section;
FIG. 4 is a perspective view of the upper housing member of FIG. 1 ; and
FIG. 5 is a perspective view of the piston of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus are to be interpreted to mean “including, but not limited to . . . ”.
Unless otherwise specified, any use of any form of the terms “connect”, “engage”, “couple”, “attach”, or any other term describing an interaction between elements is not meant to limit the interaction to direct interaction between the elements and may also include indirect interaction between the elements described.
A tri-lock disconnect system in accordance with the principles described herein may be generally described as a releasable connection for coupling a rotating tool string to a tool, transmitting loads from the tool string to the tool during normal operations of the tool string, and decoupling the tool string from the tool when so desired. While the preferred embodiment of a tri-lock disconnect system is described below in the context of a tool string consisting of a coiled tubing coupled by the disconnect to a BHA, one having ordinary skill in the art will readily appreciate that the disconnect lends itself to other applications as well. For example, a tri-lock disconnect may be inserted into a conventional drillstring between the jointed drill pipe and a downhole tool, such as a BHA. In such applications, actuation of a tri-lock disconnect to decouple the drill pipe from the BHA may be more time and cost effective than decoupling these components using traditional methods, e.g., applying a torque load to the drill pipe to unthread the drill pipe from the BHA.
Referring now to FIG. 1 , an operating environment for a coiled tubing string 105 and an operating tool 115 is shown schematically. An embodiment of a mechanically engaged and releasable connection system 100 is depicted at the lower end of the length of coiled tubing 105 disposed in a well 110 . The operating tool 115 , such as a bottom hole assembly (BHA), is coupled below disconnect 100 . Coiled tubing 105 , disconnect 100 and BHA 115 form a tool or tubing string 120 , wherein coiled tubing 105 and BHA 115 form an upper portion 125 and a lower portion 130 , respectively, of tool string 120 . Tool string 120 is positioned in a well casing 135 intersecting a downhole formation or zone of interest 140 . An annulus 160 is formed between tool string 120 and well casing 135 . Coiled tubing 105 is stored on a reel 145 at the surface 150 and is run into casing 135 and well 110 by a tubing injector 155 . Other conventional components of well 110 at the surface 150 are omitted for clarity.
Referring next to FIG. 2 , an embodiment of the tri-lock disconnect system 100 as assembled includes three working parts, specifically, a first tubular or lower housing member 205 coupled to a second tubular or upper housing member 210 and a piston 215 disposed therein. Lower housing member 205 has two ends 220 , 225 with an annular body 230 extending therebetween. End 220 of lower housing member 205 is the downhole end of disconnect 100 . As such, end 220 of lower housing member 205 may be coupled to a first tubular member, such as lower tubing portion 130 of tool string 120 ( FIG. 1 ). In this exemplary embodiment, disconnect 100 is coupled to lower tubing portion 130 by a plurality of threads 305 (best viewed in FIG. 3 ) located on an outer surface 310 of lower housing member 205 . To provide a fluid-tight coupling at this location, lower housing member 205 further includes two grooves 255 in outer surface 310 proximate threads 305 . Each groove 255 is configured to receive a sealing element, such as an O-ring, (not shown) prior to the coupling of lower housing member 205 with lower tubing portion 130 . End 225 couples to upper housing member 210 , as will be described.
Lower housing member 205 further includes a flowbore 235 extending therethrough from end 220 of body 200 and an increased diameter throughbore 240 extending therethrough from end 225 to flowbore 235 . The size of flowbore 235 is selected to allow fluid flow therethrough at a desired rate during normal operations of tool string 120 . The size and shape of throughbore 240 is selected to receive upper housing member 210 and piston 215 , as shown in FIG. 2 and described below.
Flowbore 235 of lower housing member 205 is smaller in cross-section than throughbore 240 . Thus, a shoulder 260 is formed in body 230 at the transition between flowbore 235 and throughbore 240 . Shoulder 260 limits the depth to which piston 215 may translate into lower housing member 205 .
Referring now to FIG. 3 , throughbore 240 of lower housing member 205 includes a first portion 315 , a second increased diameter portion 320 , and a third increased diameter portion 325 . First and second portions 315 , 320 are configured to receive piston 215 , while third portion 325 is configured to receive upper housing member 210 . First portion 315 is bounded by a generally cylindrical inner surface 330 of body 230 configured to sealingly engage piston 215 when piston 215 is inserted into first portion 315 of throughbore 240 , as shown in FIG. 2 . Second portion 320 is bounded by a generally cylindrical inner surface 335 . The cross-section of first portion 315 is smaller than that of second portion 320 . Thus, a shoulder 340 is formed in body 230 surrounding throughbore 240 at the transition between first and second portions 315 , 320 .
A first plurality of splines 345 is formed over a portion of inner surface 335 . Each spline 345 has a length extending substantially parallel to a longitudinal axis 365 through lower housing member 205 and a height that extends substantially radially inward from inner surface 335 . Thus, the splines 345 may also be referred to as longitudinally or axially disposed splines. A recess 346 is formed between each pair of adjacent splines 345 . Splines 345 are configured to matingly engage and interlock with another set of splines formed on the outer surface of piston 215 , as will be described. When the axially disposed interlocking splines are so engaged, they form an interlocking mechanism between lower housing member 205 and piston 215 to prevent relative rotation therebetween.
Still referring to FIG. 3 , third portion 325 of throughbore 240 is bounded by a generally cylindrical inner surface 350 of body 230 configured to sealingly engage upper housing member 210 when upper housing member 210 is inserted into third portion 325 of throughbore 240 . The cross-section of second portion 320 is smaller than that of third portion 325 . Thus, a shoulder 355 is formed in body 230 surrounding throughbore 240 at the transition between second portion 320 and third portion 325 . Shoulder 355 limits the depth to which upper housing member 210 may be inserted into lower housing member 205 .
To enable coupling of upper and lower housing members 210 , 205 , as shown in FIG. 2 , a first plurality of axially offset or spiral splines 360 are formed over a portion of inner surface 350 . Each spline 360 has a length that extends circumferentially over a portion of inner surface 350 and is angularly offset relative to longitudinal axis 365 . Thus, the splines 360 may also be referred to as longitudinally or axially offset splines. Each spline 360 also has a height that extends substantially radially inward from inner surface 350 . A recess 361 is formed between each pair of adjacent splines 360 . Spiral splines 360 are configured to matingly engage and interlock with a set of spiral splines formed on the outer surface of upper housing member 210 , as will be described. Upper and lower housing members 210 , 205 are coupled together by engaging and interlocking spiral splines 360 with matching spiral splines on upper housing member 210 to form an interlocking mechanism, as will be described. The interlocking mechanism prevents relative axial displacement between the members 210 , 205 when combined with the other components described herein.
Lower housing member 205 further includes a recirculation port 245 (best viewed in FIG. 2 ) with a burst disc 250 seated therein. Burst disc 250 is configured to rupture when fluid pressure in flowbore 235 significantly exceeds the expected pressure range of fluid passing through flowbore 235 during normal operations of tool string 120 . For example, assuming that the pressure of fluid passing through flowbore 235 during normal operations of tool string 120 is expected to be no greater than 3,000 psi, burst disc 250 may be configured to rupture at fluid pressures in excess of 5,000 psi. Once burst disc 250 ruptures, recirculation port 245 provides fluid communication between flowbore 235 and annulus 160 ( FIG. 1 ).
Turning now to FIG. 4 , upper housing member 210 has two ends 420 , 425 with an annular body 430 extending therebetween. End 420 of upper housing member 210 is the uphole end of disconnect 100 . As such, end 420 of upper housing member 210 is coupled to a second tubular member, such as upper tubing portion 125 of tubing string 120 ( FIG. 1 ). In this exemplary embodiment, disconnect 100 is coupled to upper tubing portion 125 by a plurality of threads 405 located on an outer surface 410 of upper housing member 210 . To provide a fluid-tight connection at this location, upper housing member 210 further includes two grooves 455 in outer surface 410 proximate threads 405 . Each groove 455 is configured to receive a sealing element, such as an O-ring, prior to the coupling of upper housing member 210 with upper tubing portion 125 . End 425 couples to lower housing member 205 , as will be described. To provide a fluid-tight connection at this location, upper housing member 210 further includes two grooves 455 in outer surface 410 proximate end 425 . Each groove 455 is configured to receive a sealing element, such as an O-ring, prior to the coupling of upper housing member 210 with lower housing member 205 .
Referring also to FIG. 2 , body 430 includes a throughbore 435 extending therethrough. Throughbore 435 includes a first portion 415 and an increased diameter second portion 460 . First portion 415 is bounded by a generally cylindrical inner surface 465 of body 430 , while second portion 460 is bounded by a generally cylindrical inner surface 470 of body 430 . A second plurality of splines 450 is formed on inner surface 465 . Each spline 450 has a length extending substantially parallel to a longitudinal axis 444 through upper housing member 210 and a height that extends substantially radially inward from inner surface 465 . Thus, the splines 450 may also be referred to as longitudinally or axially disposed splines. A recess 451 is formed between each pair of adjacent splines 450 . Splines 450 are similar to splines 345 formed on inner surface 335 of lower housing member 205 . Further, splines 450 , like splines 345 , are configured to matingly engage and interlock with the set of splines formed on the outer surface of piston 215 , as will be described. When the axially disposed interlocking splines are so engaged, they form an interlocking mechanism between upper housing member 210 and piston 215 to prevent relative rotation therebetween.
The cross-section of first portion 415 is smaller than that of second portion 460 . Thus, a shoulder 475 is formed in body 430 surrounding throughbore 435 at the transition between first portion 415 and second portion 460 . When upper housing member 210 is decoupled from lower housing member 205 and extracted from well 110 ( FIG. 1 ), shoulder 475 retains piston 215 within throughbore 435 of upper housing member 210 so that piston 215 is removed from well 110 with upper housing member 210 .
Upper housing member 210 further includes a second plurality of axially offset or spiral splines 440 formed over a portion of outer surface 410 proximate end 425 . Each spline 440 has a length that extends circumferentially over a portion of outer surface 410 and is angularly offset relative to longitudinal axis 444 . Thus, the splines 440 may also be referred to as longitudinally or axially offset splines. Each spline 440 also has a height that extends substantially radially outward from outer surface 410 . A recess 441 is formed between each pair of adjacent splines 440 . Spiral splines 440 are configured to matingly engage and interlock with the first plurality of spiral splines 345 formed over a portion of inner surface 335 of lower housing member 205 . Upper housing member 210 and lower housing member 205 are coupled by engaging or interlocking spiral splines 440 , 345 , as will be described below.
Upper housing member 210 further includes a recirculation port 480 through body 430 and a plurality of recesses 485 formed in inner surface 470 proximate end 420 . Recirculation port 480 provides fluid communication between flowbore 435 and annulus 160 ( FIG. 1 ). Each recess 485 is configured to receive a shear pin or screw 490 . Shear pins 490 engage a shear groove located on the outer surface of piston 215 when piston 215 is disposed within upper housing member 210 , as shown in FIG. 2 and described in more detail below.
Turning finally to FIG. 5 , piston 215 has two ends 520 , 525 with an annular body 530 extending therebetween. A flowbore 540 extends through body 530 from end 525 to end 520 . Proximate each end 520 , 525 , piston 215 further includes a pair of grooves 510 formed in an outer surface 505 of piston 215 . Each groove 510 is configured to receive a sealing element, such as an O-ring. When end 520 of piston 215 is inserted into first portion 315 of throughbore 240 of lower housing member 205 , as shown in FIG. 2 , end 520 of piston 215 sealingly engages inner surface 330 of lower housing member 205 . Similarly, when disconnect 100 , or more specifically, end 420 of upper housing member 210 , is coupled to upper portion 125 of tubing string 120 , end 525 of piston 215 sealingly engages the inner surface of upper portion 125 .
Piston 215 further includes a shear groove 515 adjacent grooves 510 proximate end 525 . When end 520 of piston 215 is inserted through upper housing member 210 and into throughbore 240 of lower housing member 205 , as shown in FIG. 2 , shear pins 490 extending from recesses 485 in upper housing member 210 engage shear groove 515 , whereby piston 215 is suspended by shear pins 490 within upper and lower housing members 210 , 205 and prevented from further translation relative to upper and lower housing members 210 , 205 . The size and quantity of shear pins 490 supporting piston 215 in this manner are selected to ensure piston 215 remains suspended when exposed to the full range of fluid pressures expected during normal operations of tool string 120 . However, when piston 215 is exposed to significantly higher pressures, such as when flowbore 540 is blocked and fluid may not pass therethrough, the pressure forces acting on piston 215 cause pins 490 to shear, thereby allowing piston 215 to displace in the downhole direction, or further into lower housing member 205 .
Piston 215 further includes a third plurality of splines 535 over a portion of outer surface 505 that were previously referenced regarding interlocking engagement with first and second pluralities of splines 345 , 450 . Each spline 535 extends substantially radially outward from outer surface 505 . Each spline 535 has a length extending substantially parallel to a longitudinal axis 555 through piston 215 . Thus, the splines 535 may also be referred to as longitudinally or axially disposed splines. A recess 536 is formed between each pair of adjacent splines 535 . Further, the axial length of splines 535 is selected such that they extend into, engage, and interlock simultaneously with both sets of first and second splines 345 , 450 of lower and upper housing members 205 , 210 , respectively. When piston 215 is inserted into lower and upper housing members 205 , 210 and suspended by shear pins 490 , as shown in FIG. 2 , splines 535 of piston 215 interlock with splines 345 , 450 of lower and upper housing members 205 , 210 , respectively. Once interlocked, upper and lower housing members 210 , 205 are prevented from rotating relative to or about piston 215 , as well as relative to each other.
Piston 215 further includes a flanged portion or stop ring 545 extending from outer surface 505 . Stop ring 540 is configured such that its cross-section is larger than that of first portion 415 of throughbore 435 of upper housing member 210 . When upper housing member 210 is decoupled from lower housing member 205 and extracted from well 110 , piston 215 is retained with upper housing member 210 by virtue of contact between shoulder 475 of upper housing member 210 and stop ring 545 of piston 215 . The interaction between shoulder 475 and stop ring 545 prevents piston 215 from translating out of throughbore 435 and instead allows piston 215 to be removed from well 110 along with upper housing member 210 .
In order to decouple upper portion 125 of tubing string 120 from BHA 115 , disconnect 100 must first be actuated. After actuation, upper housing member 210 may be decoupled from lower housing member 205 . The exemplary embodiment of a tri-lock disconnect system depicted in FIGS. 2-5 and described herein is hydraulically actuated. For this purpose, piston 215 further includes a ball seat 550 at end 525 . Other embodiments of a tri-lock disconnect system, however, may be actuated in other ways, such as by mechanical or electrical means.
To actuate disconnect 100 , a ball is dropped from the surface 150 through tool string 120 to disconnect 100 where it lands on ball seat 550 and prevents further fluid from passing into flowbore 540 of piston 215 . As a result, fluid pressure builds upstream of piston 215 until the pressure load on piston 215 causes shear pins 490 to sever. Once shear pins 490 sever, piston 215 translates downward into lower housing member 205 until abutting shoulder 260 of lower housing member 205 . When piston 215 comes to rest against shoulder 260 , splines 535 of piston 215 are fully disengaged from splines 450 on upper housing member 210 , and upper housing member 210 is free to rotate relative to lower housing member 205 .
The assembly and operation of disconnect 100 will now be described with reference to FIGS. 1 through 5 . To assemble disconnect 100 , sealing elements, such as O-rings, are inserted into grooves 455 on upper housing member 210 , grooves 510 on piston 215 , and grooves 255 on lower housing member 205 . Upper and lower housing members 210 , 205 are then coupled. End 425 of upper housing member 210 is inserted into throughbore 240 of lower housing member 205 . When spiral splines 440 on outer surface 405 of upper housing member 210 contact spiral splines 360 on inner surface 350 of lower housing member 205 , a compression load is then applied to end 420 of upper housing member 210 . Due to the angular nature of spiral splines 440 , 360 , the applied compression load causes upper housing member 210 to rotate into lower housing member 205 . As upper housing member 210 rotates into lower housing member 205 , spiral splines 440 engage and interlock with spiral splines 360 . More specifically, spiral splines 440 thread into recesses 361 between spiral splines 360 , and spiral splines 360 thread into recesses 441 between spiral splines 440 . Rotation of upper housing member 210 in this manner continues until end 425 of upper housing member 210 abuts shoulder 355 of lower housing member 205 and spiral splines 440 , 360 are fully interlocked, as shown in FIG. 2 . In some embodiments, upper housing member 210 need only be turned ¾ of a rotation to fully couple within lower housing member 205 . Further, when spiral splines 440 , 360 are fully engaged, longitudinal splines 345 on inner surface 335 of lower housing member 205 are adjacent to and align with longitudinal splines 450 on inner surface 465 of upper housing member 210 .
Next, piston 215 is inserted into upper and lower housing members 210 , 205 . End 520 of piston 215 is inserted through throughbore 435 of upper housing member 210 and into throughbore 240 of lower housing member 205 . Once end 520 of piston 215 passes into throughbore 240 , piston 215 may be rotated relative to the assembly of upper and lower housing members 210 , 205 , if necessary, to align longitudinal splines 535 on outer surface 505 of piston 215 with recesses 451 , 346 between longitudinal splines 450 , 345 on inner surfaces 465 , 335 of upper and lower housing members 210 , 205 , respectively. When longitudinal splines 535 align with recesses 451 , 346 , end 520 of piston 215 may be further inserted into throughbore 240 until shear pins 490 extending from recesses 485 of lower housing member 205 engage shear groove 515 of piston 215 , thereby preventing further translation of piston 215 within upper and lower housing members 210 , 205 .
Once shear pins 490 engage shear groove 515 and piston 215 ceases to translate, longitudinal splines 535 of piston 215 are fully interlocked with longitudinal splines 450 , 345 of upper and lower housing members 210 , 205 , respectively, as shown in FIG. 2 . When splines 535 are interlocked with splines 450 , 345 , rotation of upper and lower housing members 210 , 205 relative to piston 215 is prevented, as previously described. As long as upper and lower housing members 210 , 205 cannot rotate relative to each other, spiral splines 440 on upper housing member 440 cannot disengage or unthread from spiral splines 345 on lower housing member 205 .
Disconnect 100 is now fully assembled. Due to the engagement of longitudinal splines 535 on piston 215 with longitudinal splines 345 , 450 on lower and upper housing members 205 , 210 , respectively, lower and upper housing members 205 , 210 cannot rotate relative to piston 215 . Since such rotation is prevented, spiral splines 440 on upper housing member 210 cannot disengage or unthread from spiral splines 360 of lower housing member 205 upon application of a tension load to upper housing member 210 . Thus, disconnect 100 includes three interlocking engagements, one between piston 215 and lower housing member 205 , another between piston 215 and upper housing member 210 , and the third between upper and lower housing members 210 , 205 . Hence, disconnect 100 is also referred to as a tri-lock connection system or a tri-lock disconnect. The axially disposed interlocking engagements are in an opposed relationship with the axially offset interlocking engagement such that the anti-rotation of the axially disposed interlocking engagements reacts with the anti-translation of the axially offset interlocking engagement to couple the disconnect 100 such that the primary tubular members are fixed both rotationally and translationally. The axially disposed interlocking mechanism may be moved or disengaged to then remove the opposing reaction forces, and disengage or decouple the axially offset interlocking mechanism. The axially disposed and offset mechanisms may be axially displaced from each other, but interact to provide the opposing reaction forces for coupling and selective release. It is understood that the term “splines” as used herein does not merely include those shown in the drawings, but also other surfaces which effect the interlocking engagements described herein. The interlocking mechanisms between the various tubular members may also include teethed arrangements, tongue and groove arrangements, ridge and valley arrangements or other surfaces providing mating and interlocking engagement.
Disconnect 100 is next coupled between BHA 115 and coiled tubing 105 to form tubing string 120 . Tubing string 120 is then inserted into well 110 , and BHA 115 is operated to form well 110 . During normal operations of tubing string 120 , fluid is injected downhole through coiled tubing 105 to disconnect 100 . Fluid passes through disconnect 100 via flowbore 540 of piston 215 , throughbore 240 of lower housing member 205 , and flowbore 235 of lower housing member 205 ( FIG. 2 ). From disconnect 100 , the fluid passes through BHA 115 and then returns to the surface 150 ( FIG. 1 ) via annulus 160 . Also during normal operations, interlocked spiral splines 440 , 360 and interlocked longitudinal splines 345 , 450 allow significant loads to be transferred through disconnect 100 . Specifically, tension loads applied to disconnect 100 by coiled tubing 105 are carried by spiral splines 440 , 360 , while any torsional loads are borne by longitudinal splines 345 , 450 , 535 . These loads as well as pressure fluctuations in fluid passing through tubing string 120 during normal operations will not inadvertently actuate disconnect 100 and/or decouple upper housing member 210 from lower housing member 205 .
Actuation of disconnect 100 requires severance of shear pins 490 . Their quantity and size have been selected such that their combined strength is capable of suspending piston 215 within upper and lower housing members 210 , 215 , as shown in FIG. 2 , under the full range of fluid pressures expected during normal operations of tubing string 120 . Fluid pressure fluctuations acting on piston 215 during normal operations are insufficient to cause piston 215 to sever shear pins 490 , and thus actuate disconnect 100 . At the same time, any load applied to disconnect 100 by coiled tubing 105 acts on upper housing member 210 , not piston 215 . Hence, piston 215 is unaffected by the applied loads, and shear pins 490 remain intact.
Decoupling of upper housing member 210 from lower housing member 205 requires actuation of disconnect 100 and a tension load subsequently applied to upper housing member 205 . Due to the angled nature of spiral splines 440 , 360 on upper and lower housing members 210 , 205 , respectively, a tension load applied to disconnect 100 through coiled tubing 105 will cause upper housing member 210 to rotate relative to lower housing member 205 and spiral splines 440 to disengage from spiral splines 360 , unless rotation of upper housing member 210 relative to lower housing member 205 is prevented. Until disconnect 100 is actuated, longitudinal splines 535 on piston 215 remain fully interlocked with longitudinal splines 345 , 465 on lower and upper housing members 205 , 210 , and rotation of upper housing member 210 relative to lower housing member 205 is prevented. Hence, spiral splines 440 cannot disengage from spiral splines 360 , and upper housing member 210 cannot be decoupled from lower housing member 205 . Thus, loads applied to disconnect 100 during normal operation of tubing string 120 will not cause actuation of disconnect 100 and decoupling of coiled tubing 105 from BHA 115 .
In the event that BHA 115 becomes stuck during operation of tubing string 120 and fluid flow through BHA 115 is prevented, fluid pressure within disconnect 100 begins to rise in response. When the pressure of fluid contained within flowbore 235 of disconnect 100 exceeds the burst pressure rating of disc 250 , disc 250 ruptures. Fluid within disconnect 100 is then allowed to flow from flowbore 235 through recirculation port 245 to annulus 160 . Should it become desirable to decouple coiled tubing 105 from BHA 115 so that coiled tubing 105 may be removed from well 110 and the stuck BHA 115 subsequently retrieved, disconnect 100 may be actuated to allow upper housing member 210 to decouple from lower housing member 205 upon application of a tension load to upper housing member 210 .
To actuate disconnect 100 , a ball is dropped from surface 150 into tubing string 120 . Fluid passing through tubing string 120 carries the ball to disconnect 100 where the ball lands on ball seat 550 of piston 215 . Once seated, the ball prevents further fluid flow into flowbore 540 of piston 215 . As a result, fluid pressure upstream of piston 215 begins to build. When the fluid pressure acting on piston 215 causes piston 215 to exert loads on shear pins 490 in excess of their combined strength, pins 490 shear. Piston 215 then translates in the downhole direction, or further into throughbore 240 of lower housing member 205 , until end 520 of piston 215 abuts shoulder 260 on lower housing member 205 .
When piston 215 comes to rest against shoulder 260 , longitudinal splines 535 on piston 215 are fully disengaged from longitudinal splines 465 on upper housing member 210 , but remained interlocked with longitudinal splines 345 on lower housing member 205 . Upper housing member 210 is then free to rotate relative to lower housing member 205 and piston 215 , while lower housing member 205 is still prevented from rotational movement due to the engagement of longitudinal splines 345 on lower housing member 205 with longitudinal splines 535 on piston 215 .
A tension load is then applied to disconnect 100 via coiled tubing 105 . In response, upper housing member 210 is pulled in the uphole direction. Due to the angular nature of spiral splines 440 , 360 on upper and lower housing members 210 , 205 , respectively, upper housing member 210 rotates relative to lower housing member 205 until spiral splines 440 , 360 disengage. Once spiral splines 440 , 360 disengage, upper housing member 210 is decoupled from lower housing member 205 and returned to the surface 150 . Due to interaction between stop ring 545 on piston 215 and shoulder 475 of upper housing member 210 , piston 215 is retained within throughbore 435 of upper housing member 210 and returned to the surface 150 along with upper housing member 210 . As these components are lifted to the surface 150 , fluid contained within coiled tubing 105 flows through flowbore 435 and recirculation port 480 of upper housing member 210 to annulus 160 . After upper housing member 210 , piston 215 and coiled tubing 105 have been removed from well 110 , BHA 115 with lower housing member 205 coupled thereto may be retrieved via fishing, jarring or other operation.
The above discussion is meant to be illustrative of the principles and various embodiments of the disclosure. The disclosure is susceptible to embodiments of different forms. It is to be fully recognized that the various teachings of the embodiments discussed may be employed separately or in any suitable combination to produce desired results. Many variations and modifications of the apparatus and methods disclosed herein are possible and are within the scope of the disclosure. Accordingly, the scope of protection is not limited by the description set out above, but is only limited by the claims which follow, that scope including all equivalents of the subject matter of the claims. | An apparatus for mechanically engaging and releasably coupling two tubular members may include a first housing member, a second housing member and a piston member, wherein, in a first position, the first and second housing members are fixed relative to each other by the piston, and wherein, in a second position, the second housing member is rotatable relative to the first housing member. Certain embodiments include matingly engaged axially disposed and axially offset splines. Other embodiments include first and second interlocking mechanisms that are in an opposed relationship to couple first and second tubular members in a fixed position. Some embodiments include a method of reacting a first rotational coupling against a second axial coupling to resist both axial and rotational movement between first and second tubulars. Other embodiments include displacing a moveable member to both axially and rotationally release first and second tubulars. | 4 |
This invention was made with government support under Contract No. DAAG 4683-K-0163 awarded by the Department of the Army. The government has certain rights in this invention.
This is a continuation of copending application Ser. No. 07/458,173 filed on Dec. 28, 1989, now abandoned, which is a continuation of application Ser. No. 06/901,766 filed on Aug. 28, 1986, now U.S. Pat. No. 4,891,337.
BACKGROUND OF THE INVENTION
The so-called thermite reaction traditionally involves the exothermic reduction of iron oxide with aluminum, in which the reaction produces molten iron with an aluminum oxide slag floating thereon, the reaction taking place either in a suitable mold so that the molten iron is fusion cast into a desired shape or at a site where two metal parts are to be joined to produce a weld between such metal parts when the reaction is completed.
Although there are prior patents which involve the use of the thermite type reaction to produce borides, carbides, silicides and nitrides and the like, the product produced by the reaction is of at least two phases, one which is a layer of the boride, carbide, etc., and another which is a layer of the oxide of the reducing metal such as aluminum or magnesium. That is, the reducing metal oxide is present as a separate layer of slag, as in the classical thermite reaction. If special steps are taken to produce a composition which is a mixture of the boride, carbide, etc. and the reducing metal oxide, such composition is not a foamed product.
UK Pat. No. 1,497,025 teaches the production of cast refractory inorganic products by a thermite type reaction in which slag is formed and the product is a dense, sintered form. Thus, the teaching of this patent is directed to producing a composition which is not a mixture, homogeneous or otherwise, of all the reaction products, but of a composition which is a mixture of the reaction products less the oxide of the reducing metal and (to the extent possible) less the CO which is formed during the reaction. This patent is specifically directed to avoid "poorly sintered specimens" of the desired product and to avoid products which are characterized by "porosity and the presence of free carbon therein, which affects their strength". To this end, the patent teaches a method which is carried out at a centrifugal acceleration of from 100 to 1,500 g and in a gaseous medium under pressure of 1 to 100 atm, using an inert gas such as argon. In this patent, the reaction mixture contains carbon and a reducing metal such as aluminum plus one or more metal oxides. The end product in each case is divided into two layers, a top layer of slag which is the reducing metal oxide and the bottom layer which is the desired material. Even if the contraints taught by this patent are not followed and porosity is present, it is not present in a composition which includes the reducing metal oxide.
Present techniques of producing refractory, monolithic shapes involve initial shape-forming steps such as hydraulic or isostatic pressing, slip-casting, extrusion, injection molding and the like prior to the firing step. Moreover, the firing step normally involves at least preheating the entire reaction mixture either to ignition temperature or to an elevated temperature at which local ingnition and subsequent completion of the reaction occurs.
The invention is directed to improvements over existing techniques.
In contrast to the prior art teachings, the invention herein relates to the discovery that precisely shaped, foamed, monolithic and thus highly insulative refractory articles may be produced in situ by controlling the particulate sizes of the reaction components which form the reactive mixture and the composition of the article being a substantially homogeneous dispersion of the products of reaction.
The invention relates to monolithic, shaped refractory articles which are of foamed nature yielding densities substantially less than the theoretical density of the composition of the article, and the method of making such articles.
This invention involves a powdered exothermic reaction mixture which may be loosely packed into a desired self sustaining shape and dimensions which, after local ignition and resultant reaction in air under ambient conditions, yields a foamed, monolithic article faithfully reproduced in the desired shape and dimensions.
The composition of the article is a substantially homogeneous mixture of the reaction products of the reaction mixture.
The foamed nature of the article, yielding a density less than that of the theoretical density of the composition of the article; and the ability of the reaction mixture to complete its reaction after local ignition in air under ambient conditions and to yield an article faithfully reproducing the shape and dimensions into which the reaction mixture has been loosely packed, are attained by controlling the particle sizes of the components of the reaction mixture and employing aluminum as the reducing metal of the exothermic reaction mixture.
The compositions of the articles of this invention are the reaction products of a thermite type reaction substantially homogeneously dispersed throughout the article and the article itself is characterized by its foamed nature and its faithful reproduction of the dimensions and shape into which the reaction mixture has been loosely packed.
The composition of the articles of this invention is preferred to be TiB 2 in Al 2 O 3 .
The reactive mixture of this invention is easily shaped by lightly packing it in a mold cavity defining the desired shape and dimensions of the article, the material defining the mold cavity being made of any suitable material which is capable of withstanding the temperatures involved during the reaction and which do not require great structural integrity other than to confine the lightly packed reactive mixture and retain the desired shape of the article before and during the reaction.
Moreover, the particulate size control renders the molded reactive mixture locally ignitable in air under atmospheric conditions without preheating the mass thereof, after which ignition the reaction proceeds to completion throughout the reaction mixture to produce the shaped article.
The method of this invention, then, is both energy and cost efficient and of minimal complexity, capable of allowing the production of shaped articles of highly refractory, insulating properties due not only to the composition of the article but also to the foamed nature thereof.
Insofar as the critical feature of particulate sizes of the components of the reaction mixture is concerned, I have found that all components must be of powder form to pass a screen of 50 mesh size, that is, not being retained on mesh size of larger openings. By mesh size is meant U.S. Standard mesh.
However, with respect to the ability of the reaction mixture to be ignited locally and thereafter react to completion in air under ambient conditions it has been found that the reaction mixture must contain a substantial amount of TiO 2 which is of -300 mesh size, of B 2 O 3 which is of -100, +200 mesh size or less and of Al which is of -100, +200 mesh size or less.
The method of this invention does not require a special environment or other special preparation and/or reaction procedures such as preheating the reaction mixture mass, the use of controlled atmosphere during reaction, the application of centrifugal effect before or during reaction or the use of pressure to pre-form the reaction mixture. The "green" condition of the shaped reaction mixture prior to ignition is simply as a mass of powder which is loosely packed so as to attain the desired shape. Under these circumstances, ignition takes place in response to local heating in air at atmospheric pressure and may be effected by local heating as by a resistance heated nichrome wire until ignition occurs, whereafter the exothermic reaction progresses through the reaction mass until complete. A further advantage of the present invention is that the reaction achieves a less violent conversion of reactants to product than prior thermite reactions.
In accord with this invention, it is to be noted that the article formed is a composition derived from the two oxides which are present in the reaction mixture. Although it is preferred that this composition be that which results from stoichiometric amounts of these two components and of the reducing metal, it is not strictly necessary for successful compositions. For example, when titanium dioxide (TiO 2 ) and boron oxide (B 2 O 3 ) are combined with aluminum in the reaction mixture, an excess of boron oxide will produce a composition which is titanium diboride (TiB 2 ) plus the excess boron oxide plus aluminum oxide (Al 2 O 3 ) formed during the reaction. Similarly, if the reaction mixture were formed of stoichiometric amounts of the two oxides and an excess of the reactive metal aluminum, the product would be titanium diboride plus aluminum plus aluminum oxide.
The above and other objectives of the invention will become more apparent as the description proceeds.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a microphotograph illustrating the ideal, substantially homogeneously foamed nature of products made according to the invention;
FIG. 2 is a photograph of a shaped refractory product of the present invention;
FIG. 3 is a vertical section taken through an SCFS crucible containing a reaction powder mixture according to this invention and having a core of powdered alumina, prior to ignition;
FIG. 4 is a view similar to FIG. 3 but illustrating the product attained after ignition and cooling and before removal of the core; and
FIG. 5 is an X-ray diffraction chart of products formed by the invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference to FIG. 1 illustrates the ideal, substantially homogeneously foamed nature of products made according to this invention. The article whose microphotograph is illustrated in FIG. 1 has the composition TiB 2 -Al 2 O 3 and is a highly refractory and hard product having a density of less than about 50% of the theoretical density of the composition, titanium diboride plus alumina. The following Examples will demonstrate the invention.
EXAMPLE 1
The stoichiometric reaction mixture consisting of 8.34 parts by weight TiO 2 of -300 mesh particle size, 9.39 parts by weight B 2 O 3 of -100, +200 mesh particle size, 7.27 parts by weight Al of -100, +200 mesh particle size, intimately mixed, formed the powdered reaction mixture. An amount of this mixture was loosely packed in a slip-cast fused silica (SCFS) crucible 10 as in FIG. 3 between the crucible and a suitably shaped core (not shown) and the core was removed to leave the shaped reaction mixture mass 12 within the crucible 10. The core space was then filled with -200, +300 Al 2 O 3 powder 14 and the reaction mixture was ignited in air under ambient conditions by means of an electrically heated nichrome wire (not shown). The ignition temperature was 1577° F. Upon ignition, the exothermic reaction proceeded throughout the reaction mass at a rate of about 25 mm/sec. to completion. The appearance of the reacted mixture and core material C was as is shown in FIG. 4, the article P having a homogeneously foamed nature as in FIG. 1, whose outer surface assumed the exact shape of the inner surface of the crucible 10 and whose inner surface assumed substantially the same shape as the originally formed core space. The core C was of substantially the same composition as the starting filler material 14 (alumina) and although fused by the heat of the reaction, was easily removed from the crucible shape of the article P. The weight per volume of the article P was found to be about 1.44 gm/cm 3 which, based upon the theoretical density of the composition of the article, represents about 30-40% thereof.
FIG. 2 is a photograph of the resulting article P. FIG. 5 illustrates a typical X-ray diffraction trace of the article P and indicates that the composition of the article is TiB 2 and Al 2 O 3 . X-ray diffraction traces of samples of other articles obtained from reaction of the aforesaid reaction mixture in air or argon under pressure of 1-100 atmospheres showed little, if any, difference in composition, although in samples which had been ignited in air under pressure, small amounts of TiN could be observed. Also, samples ignited and reacted in argon under pressure tended to densify and begin phase separation.
EXAMPLE 2
In this example, the same stoichiometric components of the reaction mixture were uniformly mixed but in this case, the particulate size of the Al was changed to -300 mesh, the reaction mixture otherwise being the same as in Example 1. When this reaction mixture was subjected to local heating as in Example 1, ignition took place at 1230° F. but the resultant article was not homogeneously foamed as was the case with Example 1 and as depicted in FIG. 1. Instead, the porosity was uneven so that uniform refractory performance was not attained.
EXAMPLE 3
In this example, the same stoichiometric components of the reaction mixture were uniformly mixed but in this case, the particulate size of the B 2 O 3 was changed to -300 mesh, the reaction mixture otherwise being the same as in Example 1. The reaction mixture was ignited in air as in Examples 1 and 2 by local heating. Even though the crucible shattered during the reaction, the reaction product resulted in a foam similar to that of Example 1 which retained the crucible shape. The weight of the material after ignition was 23 grams, less than that of Example 1.
EXAMPLE 4
In this example, the same stoichiometric components of the reaction mixture were uniformly mixed but in this case all three of the components were -300 mesh particle size. Again, ignition was by local heating in air. The reaction proceeded as in Example 7 with the crucible being shattered. The reaction product was a foam similar to that of Example 7 except that the center melted. The weight of the material after ignition was 21.5 grams.
EXAMPLES 5-8
In these Examples all of the remaining eight possible particulate size combinations of -100, +200; -300 of the reaction mixture were made and ignition attempted. However, none both ignited and sustained the reaction in air under ambient conditions as in Examples 1 and 2 and no article, foamed or otherwise was formed.
EXAMPLE 9
In this Example, three parts by weight of the reaction mixture of Example 2 was mixed with one part by weight of the reaction mixture of Example 1. Ignition in air under ambient conditions took place and the reaction went to completion, producing an article which was substantially homogeneously foamed as in FIG. 1 and having about the same density Thus, the presence of about 25% of the TiO 2 of -300 mesh size with the remainder being of -100, +200 mesh size improved the foaming characteristic of Example 2 to the ideal, substantially homogeneous foamed article.
EXAMPLE 10
It was noted that if the powder was loosely placed in a crucible which did not restrict the shape, a friable, loose homogeneous mass was obtained. | The method of making a foamed, low density shaped refractory product consisting of TiB 2 and Al 2 O 3 which comprises the steps of foaming an exothermic reaction mixture consisting of TiO 2 , B 2 O 3 and Al, loading the reaction mixture into a self sustaining shape, locally igniting the shaped reaction mixture in air at ambient conditions and recovering the foamed, low density, shaped refractory product. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON ATTACHED MEDIA
[0002] Not Applicable
TECHNICAL FIELD
[0003] The present invention relates to garbage collection as an automatic memory management method in a computer system, and particularly to the implementation of a write barrier component as part of the garbage collector and application programs.
BACKGROUND OF THE INVENTION
[0004] Garbage collection in computer systems has been studied for about fifty years, and much of the work is summarized in R. Jones and R. Lins: Garbage Collection: Algorithms for Dynamic Memory Management, Wiley, 1996. Even since the publication of this book, the field has seen impressive development due to commercial interest in Java and other similar virtual machine based programming environments.
[0005] The book by Jones & Lins discusses write barriers on a number of pages, including but not limited to 150-153, 165-174, 187-193, 199-200, 214-215, 222-223. Page 174 summarizes the research thus far: “For general purpose hardware, two systems look the most promising: remembered sets with sequential store buffers and card marking.”
[0006] David Detlefs et al: Garbage—First Garbage Collection, ISMM'04, pp. 37-48, ACM, 2004, which is hereby incorporated herein by reference, on p. 38 describes a modern implementation of a remembered set buffer (RS buffer) as a set of sequences of modified cards. They can use a separate background thread for processing filled RS buffers, or may process them at the start of an evacuation pause. Their system may store the same address multiple times in the RS buffers. Other documents describing various write barrier implementations include Stephen M. Blackburn and Kathryn S. McKinley: In or Out? Putting Write Barriers in Their Place, ISMM'02, pp. 175-184, ACM, 2002; Stephen M. Blackburn and Antony L. Hosking: Barriers: Friend or Foe, ISMM'04, pp. 143-151, ACM, 2004; David Detlefs et al: Concurrent Remembered Set Refinement in Generational Garbage Collection, in USENIX Java VM'02 conference, 2002; Antony L. Hosking et al: A Comparative Performance Evaluation of Write Barrier Implementations, OOPSLA'92, pp. 92-109, ACM, 1992; Pekka P. Pirinen: Barrier techniques for incremental tracing, ISMM'98, pp. 20-25, ACM, 1998; Paul R. Wilson and Thomas G. Moher: A “Card-Marking” Scheme for Controlling Intergenerational References in Generation-Based Garbage Collection on Stock Hardware, ACM SIGPLAN Notices, 24(5):87-92, 1989.
[0007] A problem with card marking is that it performs a write to a relatively random location in the card table, and the card table can be very large (for example, in a system with a 64-gigabyte heap and 512 byte cards, the card table requires 128 million entries, each entry typically being a byte, though a single bit could also be used with some additional overhead). The data structure is large enough that writing to it will frequently involve a TLB miss (TLB is translation lookaside buffer, a relatively small cache used for speeding up the mapping of memory addresses from virtual to physical addresses). The cost of a TLB miss on modern processors is on the order of 1000 instructions (or more if the memory bus is busy; it is typical for many applications to be constrained by memory bandwidth especially in modern multi-core systems). Thus, even though the card marking write barrier is conceptually very simple and involves very few instructions, the relatively frequent TLB misses with large memories actually make it rather expensive. The relatively large card table data structures also compete for cache space with application data, thus reducing the cache hit rates for application data and reducing the performance of applications in ways that are very difficult to measure (and ignored in many academic benchmarks).
[0008] What is worse, the cards need to be scanned later (usually latest at the next evacuation pause). While the scanning can sometimes be done by idle processors in a multiprocessor (or multicore) system, as applications evolve to better utilize multiple processors, there will not be any idle processors during lengthy compute-intensive operations. Thus, card scanning must be counted in the write barrier overhead.
[0009] A further, but more subtle issue is that card scanning requires that it must be possible to determine which memory locations contain pointers within the card. In general purpose computers without special tag bits, this imposes restrictions on how object layouts must be designed, at which addresses (alignment) objects can be allocated and/or may require special bookkeeping for each card.
[0010] Applications greatly vary in their write patterns. Some applications make very few writes to non-young objects; some write many times to relatively few non-young locations; and some write to millions and millions of locations all around the heap.
[0011] It is desirable to avoid the TLB misses, cache contention and card scanning overhead that are inherent in a card marking scheme. It would also be desirable to eliminate the duplicate entries for the same addresses and the requirement for a separate buffer processing step (that relies on the availability of idle processing cores) that are inherent in using sequential store buffers with remembered sets.
[0012] Some known systems maintain remembered sets as a hash table, and access the remembered set hash tables directly from the write barrier, without the use of a remembered set buffer. Such systems have been found to have poorer performance in Antony L. Hosking et al: A Comparative Performance Evaluation of Write Barrier Implementations, OOPSLA'92, pp. 92-109, ACM, 1992 (they call it the Remembered Sets alternative). They also discuss the implementation of remembered sets as circular hash tables using linear hashing on pp. 95-96. It should be noted that they are discussing how their remembered sets are implemented; their write barrier (pp. 96-98) does not appear to be based on a hash table and they do not seem to implement a write barrier buffer as a hash table. The remembered sets are usually much larger than a write barrier buffer, and thus accessing remembered sets directly from the write barrier results in poorer cache locality and TLB miss rate compared to using a write barrier buffer as described later herein, in part explaining the poor benchmark results for their hash table based remembered set approach.
[0013] It should be noted that the remembered set data structures and the write barrier buffer are two different things and they perform different functions. The write barrier buffer collects information into a relatively small data structure as quickly as possible, and is typically emptied latest at the next evacuation pause, whereas the remembered sets can be very large on a large system and are slowly changing data, and most of the data in remembered sets lives across many evacuation pauses, often through the entire run of the application.
[0014] Multiplicative hash functions, open addressing hash tables, and linear probing are described in D. Knuth: The Art of Computer Programming: Sorting and Searching, Addison-Wesley, 1973, pp. 506-549.
[0015] Lock-free hash tables allowing concurrent access are discussed e.g. in H. Gao et al: Efficient Almost Wait-free Parallel Accessible Dynamic Hashtables. CS-Report 03 -03, Department of Mathematics and Computer Science, Eindhoven University of Technology, Eindhoven, The Netherlands, 2003; H. Gao: Design and Verification of Lock-free Parallel Algorithms, PhD Thesis, Wiskunde en Natuurwetenschappen, Riksuniversiteit Groningen, 2005, pp. 21-56; David R. Martin and Richard C. Davis: A Scalable Non-Blocking Concurrent Hash Table Implementation with Incremental Rehashing, 1997; Maged M. Michael: High Performance Dynamic Lock-Free Hash Tables and List-Based Sets, SPAA'02, pp. 73-82, ACM, 2002; Ori Shalev and Nir Shavit: Split-Ordered Lists: Lock-Free Extensible Hash Tables, J. ACM, 53(3):379-405, 2006; H. Gao: Design and Verification of Lock-free Parallel Algorithms, PhD Thesis, Wiskunde en Natuurwetenschappen, Riksuniversiteit Groningen, 2005, pp. 21-56.
[0016] Other references on the use of non-blocking or lock-free algorithms in garbage collection include e.g. M. P. Herlihy and J. E. B. Moss: Lock-Free Garbage Collection for Multiprocessors, IEEE Transactions on Parallel and Distributed Systems, 3(3):304-311, 1992; F. Pizlo et al: STOPLESS: A Real-time Garbage Collector for Multiprocessors, International Symposium on Memory Management (ISMM), ACM, 2007, pp. 159-172.
[0017] Various atomic operations, including compare-and-swap and load linked/store conditional, have been extensively analyzed in the literature. Possible starting points into the literature include H. Gao and W. H. Hesselink: A general lock-free algorithm using compare-and-swap, Information and Computation, 205(2):225-241, 2007 and Victor Luchangco et al: Nonblocking k-compare-single-swap, SPAA'03, pp. 314-323, ACM, 2003.
[0018] Many software transactional memory implementations use multiversion concurrency control for read locations, saving a copy of a read object when the object is read. A hash table is frequently used for quickly finding the saved value of a memory location based on its address. Some software transactional memory systems may also save old values of written locations that can be used to restore the memory locations to their original values should the transaction need to be aborted. Again, a hash table may be used for quickly finding such values. These approaches are largely modeled after similar approaches in disk-based transactional database systems, where a log is typically used for storing the old values.
BRIEF SUMMARY OF THE INVENTION
[0019] A lock-free write barrier implementation based on hash tables with various optimizations will be presented. The focus is on what happens in the slow path of the write barrier (i.e., when the written address needs to be recorded) and in write barrier related processing steps sometimes more considered part of the garbage collector or sometimes performed by a background thread.
[0020] The objective is to reduce the overall overhead in a garbage collecting system due to the write barrier and related functionality, and to leave more freedom in other design tradeoffs relating to object layouts and access to old values of written cells.
[0021] The objective could also be partially paraphrased as eliminating the TLB misses due to updating the very large card table, eliminating card scanning or RS buffer scanning time and overhead, and optimizing updating remembered sets based on information saved by the write barrier. The new write barrier method also makes it possible to save the original value of written cells, which is beneficial or even required in some garbage collection systems well suited for multiprocessor systems with very large memories, such as the multiobject garbage collector presented in U.S. Ser. No. 12/147,419.
[0022] A write barrier buffer (also called remembered set buffer or RS buffer in the literature) according to the present invention uses a lock-free open addressing hash table, preferably with a multiplicative hash function, to implement the write barrier buffer. Each written address is stored only once in the hash table. The size of the hash table may be dynamically adjusted to keep collisions under control.
[0023] A significant performance improvement in the present method comes from avoiding the TLB miss that is frequently associated with card marking with large memories. A TLB miss costs about the same as a thousand simple instructions (the cost having steadily increased year-by-year as processor cores become relatively faster and faster compared to memory speeds). Thus, even though a write barrier according to the present invention executes more instructions than a traditional card marking based write barrier, those instructions execute much faster in modern systems.
[0024] In some preliminary tests (single-threaded, but with atomic instructions) we found a hash table insertion into a reasonably sized hash table to consume about 19 nanoseconds on an AMD 2220 processor, compared to about 189 nanoseconds for marking a card, and 11 vs. 34 ns on an Intel i7 965 processor (8 GB memory, 512 byte cards). The difference is mostly due to a lower TLB miss rate associated with the hash table.
[0025] The methods of the present disclosure are particularly beneficial in computer systems with large memories and incremental (or real-time) garbage collection. Such systems generally must maintain remembered sets anyway, and can benefit significantly from combining writes to the same address. The benefit becomes greater as the complexity of the remembered set data structures increases; the cost generally tends to become higher in systems utilizing concurrency or designed for very large memories, distributed systems, and persistent storage systems. Thus, the highest benefit from the present invention can be realized in such systems.
[0026] A further benefit is allowing more freedom for designing other parts of the garbage collector. There is no need to scan cards (which requires knowing which memory locations contain valid pointers and which are other data, such as raw integers or floating point numbers). The old value of each written location can be made easily available to the garbage collector, which is difficult to do consistently and efficiently in a log-structured RS buffer based scheme. Pause times are reduced by having each written memory location in the remembered set buffer exactly once.
[0027] In mobile computing devices, such as smart phones, personal digital assistants (PDAs) and portable translators, reduced write barrier overhead translates into lower power consumption, longer battery life, smaller and more lightweight devices, and lower manufacturing costs. The hash table based write barrier, due to its lower memory requirements, is also more amenable to direct VLSI implementation.
[0028] In large computing systems with very large memories, using a lock-free hash table based write barrier both reduces memory requirements and improves overall performance of the entire system. The increased flexibility allows implementing other parts of the garbage collector and the rest of the execution environment more optimally, resulting in indirect benefits.
[0029] The focus of the present disclosure is on the write barrier component and improvements thereto, and the mechanisms disclosed herein can be used in a garbage collector regardless of whether its remembered sets are organized as a global hash table, a hash table per region, a global index tree, an index tree per region, or some other suitable data structure, or entirely non-existent in the traditional sense.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)
[0030] FIG. 1 illustrates a computer system with a lock-free hash table based write barrier buffer for a multiprocessor garbage collector.
[0031] FIG. 2 illustrates the fast path component.
[0032] FIG. 3 illustrates the slow path component from a data flow viewpoint.
[0033] FIG. 4 illustrates lock-free insertion of an address and old value into a write barrier buffer implemented as an open addressing hash table.
[0034] FIG. 5 illustrates the slots and fields of the write barrier buffer hash table.
[0035] FIG. 6 illustrates a computer usable software distribution medium for causing a computer system to implement a write barrier buffer as described herein.
DETAILED DESCRIPTION OF THE INVENTION
[0036] A computing system according to the present invention comprises a garbage collector means for managing memory. Any known or future garbage collection means can be used (many such methods are described in the book by Jones & Lins).
[0037] Known garbage collection methods for general purpose computers that are suitable for systems with large memories requiring incremental collection utilize a write barrier to record certain information about written memory locations. Which writes need to be recorded and what information needs to be recorded about them varies from system to system. However, the write barrier implementation can be considered relatively independent of the particular garbage collection method selected.
[0038] The write barrier is a key interface between the application programs being executed on the computing system and the garbage collector/memory manager component. This structure is illustrated in FIG. 1 , which shows a computing system according to the present invention. The key hardware components of a general-purpose computer, such as processors ( 101 ), main memory ( 102 ), storage subsystem ( 103 ) and network interface(s) ( 104 ) that connect the computing system to a data communications network ( 117 ) are well known in the art. Modern high-end computer systems comprise several processors and several hundred megabytes to tens of gigabytes of fast main memory that is directly accessible to the processors. Clustered computing systems may employ thousands of computing devices working in tandem, and may utilize distributed garbage collection and/or distributed shared memory, with some or all nodes incorporating a write barrier buffer according to the present disclosure.
[0039] A general purpose computer is configured for a particular task using software, that is, programs loaded into its main memory. Without the programs, the computer is useless; the programs make it what it is and control its actions and processes. Most of the essential components of a modern computer are software constructs; while composed of states in memory, they control the tangible activity of the computer by causing it to perform in a certain manner, and thus have a physical effect.
[0040] The programs for configuring the computer are normally stored in its storage system (or in the storage system of another computer accessible over the network), and are loaded into main memory for execution.
[0041] A general purpose computer generally comprises at least one operating system loaded into its main memory, and one or more application programs whose execution is facilitated, monitored and controlled by the operating system.
[0042] Modern operating systems and applications typically use garbage collection to implement automatic memory management. Such automatic memory management carries significant benefits by improving program reliability and reducing software development costs. A key obstacle for widespread use of garbage collection in the past has been overhead, but improvements in processor performance as well as better garbage collection methods have made it possible to utilize it on a broad range of systems.
[0043] The garbage collector component in the system may technically be part of the operating system, part of some or all application programs, or a special middleware or firmware component, such as a virtual machine shared by many applications. Some or all of the garbage collector may also be implemented directly in hardware; it can be anticipated that as Java and other languages utilizing garbage collection become even more widespread, the pressure for supporting some operations, such as a write barrier, in hardware will increase. Some computing systems employ multiple garbage collectors simultaneously, e.g. one for each application that needs one.
[0044] An application that utilizes garbage collection typically uses a write barrier to intercept some or all writes to memory locations by the application. The write barrier comprises a number of machine instructions that are typically inserted by the compiler before some or all writes (many compilers try to minimize the number of write barriers inserted, and may eliminate the write barrier if they can prove that the write barrier is never needed for a particular write). Some compilers may support a number of specialized write barrier implementations, and may select the most appropriate one for each write.
[0045] The write barrier can generally be divided into a fast path and a slow path component. The fast path is executed for every write, whereas the slow path is only executed for writes that actually need to be recorded (usually only a few percent of all writes). Both may be implemented in the same function, but more frequently (for performance reasons) the fast path is inlined directly where the write occurs, whereas the slow path is implemented using a function call. Some write barrier implementations only consist of a fast path with a few machine instructions, but these barrier implementations tend to have rather limited functionality and are generally not sufficient for large systems.
[0046] In the preferred embodiment of the invention described herein, the application programs ( 105 ) comprise any number of write barrier fast path instantiations ( 106 ). In the figure, it is assumed that the slow path ( 107 ) is implemented only once in the garbage collector ( 108 ), in some kind of firmware, virtual machine, or library; however, it could equally well be implemented in each application, in the operating system, or, for example, partially or entirely in hardware.
[0047] The slow path of the write barrier stores information about writes to the write barrier buffer hash table ( 109 ). During evacuation pauses, the write hash table is also used by the code that implements garbage collection ( 110 ) (typically implementing some variant of copying, mark-and-sweep, or reference counting garbage collection) or code that runs in parallel with mutators in a separate thread and updates remembered sets ( 111 ) using information in a remembered set buffer. Most garbage collectors have one remembered set per independently collectable memory region ( 112 ) or generation, though this need not necessarily be the case.
[0048] The garbage collector reads information from the hash table using an iteration means ( 113 ). It also empties the hash table; preferably this emptying is combined with the iteration means. The garbage collector may also make queries to the write barrier buffer based on the address, as the write barrier buffer is a hash table and it can be checked very quickly whether a particular address is in the hash table. A resizing means ( 114 ) is used to handle situations where the hash table becomes too full, as described below.
[0049] The main memory typically also comprises a nursery ( 115 ) used for very young objects. In most systems, the write barrier need not record writes to the nursery, and the fast path of the write barrier typically checks whether the write is to the nursery, and only calls ( 116 ) the slow path if it is not.
[0050] The fast path component ( 200 ) is described in FIG. 2 . First, in ( 201 ) the fast path tests whether the write is to the nursery or otherwise filtered. If the write is to the nursery, nothing more needs to be done by the write barrier, and execution proceeds to ( 204 ) to perform the actual write.
[0051] The test in ( 201 ) is intended to cover all sorts of filtering operations that may occur in the write barrier fast path (additional filtering may also occur in the slow path). Such filtering may e.g. filter out stores of constant values, writes to the nursery, writes whose values are within the same region as the written address, popular objects, writes whose value is in an older generation, etc. Many such filtering mechanisms are known in the literature, and which ones are used in a particular implementation depends on the details of the garbage collector, the compiler, and the architecture.
[0052] In the preferred embodiment, the next step ( 202 ) starts computing the index into the hash table, already before calling the slow path in ( 203 ). This differs from the prior art. Since most modern high-performance general purpose processors are superscalar (i.e., they can execute multiple, typically about three instructions in parallel), it is possible to start a computation that takes several clock cycles, and move on to do other processing before the value of the computation is actually needed. By starting the computation of the index into the hash table already in the fast path, its computation is overlapped with the function call, and thus the index gets computed at nearly zero extra cost compared to the function call.
[0053] The preferred embodiment computes the index into the hash table by multiplying the address of the memory location being written by a large constant using 32-bit or 64-bit multiplication combined with selecting the highest bits of the result (currently we prefer 32-bit multiplication, ignoring the upper 32 bits of a 64-bit memory address in the computation of the hash value). The multiplication is by a suitable constant that causes the result to overflow and the high-order bits of the result to depend roughly equally on all bits of the memory address (or its lower 32 bits). The index into the hash table is taken from the high order bits, as the bits of the address are more uniformly mixed here.
[0054] In all simplicity, the index computation is:
[0000] index=(( U Int32)addr* c )>>shiftcount.
[0055] This is very simple to implement in software (roughly two instructions) when the multiplication is a 32-bit or 64-bit integer multiplication; however, in custom logic the multiplication is quite expensive, and any known hash function with an output of the suitable size could be used instead. The cryptographic literature contains extensive teachings on how to construct efficient hash functions for hardware implementation with good diffusion and mixing properties (the hash function used here does not need to be cryptographically strong, however). In implementations where the hash table size is not expanded, the shift may have a constant count, may be replaced by a bitwise-and operation, or may perhaps be entirely omitted if the hash table size is e.g. 2̂8, 2̂16, or 2̂32.
[0056] Separating the computation of the hash value from other hash table operations and initiating it already in the fast path, utilizing the parallelism inherent in modern superscalar processors, allows the computation to be performed at essentially zero cost (the latency of a multiplication followed by a shift is of the same order of magnitude as a function call, so they parallelize very nicely). This alone reduces the cost of hash table operations by several percent, possibly some tens of percent, when all data is already in cache (which will be relatively frequent with hash table based write barrier buffers, as the hash table will be much smaller than a card table), and is thus an important improvement over existing methods.
[0057] In ( 203 ) the slow path is called, giving the address and the index to it as an argument (in an actual implementation on e.g. current Intel or AMD processors, the processor does not stall waiting for its computation to complete so it actually runs in parallel with the call). Other arguments may also be given, such as an address of the header or cell of the object containing the written address.
[0058] Finally, in ( 204 ) the new value is written to the memory location, or more precisely, writing it is scheduled into the execution unit of the processor. An earlier read ( 403 ) from the same location may still be executing at this point, in which case the write may need to be delayed until the earlier write has completed. Note, however, that modern superscalar processors can handle such situations without stalling the execution of other instructions that do not depend on the results of the read and write. Thus the write here does not typically reduce the benefits of performing ( 403 ) and ( 404 ) interleaved with other activity.
[0059] At ( 205 ) execution of the application program (mutator) continues after the write.
[0060] Alternatively or in addition to starting the index computation before the call to the slow path one could also start reading the old value of the written memory location (also at ( 202 )). However, currently it seems that the best mode is to not start the read yet in the fast path, because the old value is only needed if the address is not already in the hash table, and because on many processors compare-and-swap instructions would wait for the read to complete, actually reducing performance. In some embodiments the filtering step may also need the old value. As an alternative, the fast path could also start computing the hash value or read before the filtering step ( 201 ).
[0061] FIG. 3 illustrates the data flow of the slow path of the write barrier (the computation of the index is also shown here, as it could be implemented in the slow path, although in the preferred mode it is started already in the fast path). ( 301 ) is the address; this is passed to logic ( 303 ) that computes a hash value from it (in the preferred mode in software a multiply instruction, but in hardware implementations this would likely be a hash function implemented directly using logic elements). The bit selection module ( 304 ) selects the desired number of bits from the hash value (in the preferred mode, by shifting the value right; the shift count is N−M, where the word size for the multiply was 2̂N (N usually 32 or 64), and 2̂M is the size of the hash table. ( 305 ) stands for the module for performing lock-free insertion of the address and the old value ( 302 ) of the written memory location into the hash table.
[0062] FIG. 4 gives a more detailed description of the slow path ( 400 ), and especially the lock-free insertion of the address and the old value of the address into the hash table.
[0063] Step ( 401 ) illustrates the use of an atomic compare-and-swap (CAS) instruction. Such instructions are well known in the art. A compare-and-swap instruction reads a memory location, compares it against a given expected value, and if they match, writes a given new value to the memory location. In each case it returns the old value of the memory location (the return value and the way of returning it differs slightly between architectures), all as a single atomic operation with respect to serialization of operations on a multiprocessor or multi-core computer. Alternatively, the same effect can be achieved by using load linked/store conditional instructions, double compare-and-swap (DCAS), or other similar equivalent instruction sequences as is well known in the art.
[0064] As used in ( 401 ), the memory location compared and modified in the compare-and-swap operation is preferably ‘&ht[idx].addr’, meaning the address of the written address field in the hash table slot at the index computed in ( 303 ) and ( 304 ). The old value is the special value used to indicate that the slot is free, preferably 0. The new value to be assigned is the address of the written memory location in the application (i.e., the address for which the write barrier was called). The compare-and-swap instruction returns the old value of the modified location (or e.g. indicates by processor flags whether the write occurred, depending on architecture, as is known in the art).
[0065] In ( 402 ), it is checked whether the compare-and-swap instruction successfully modified the memory location (in the preferred embodiment, by comparing the returned value against the special value, preferably 0). If it was successful, execution continues from ( 403 ), where a read of the original value (old value) of the written memory location is initiated, and ( 404 ), where a write of the original value into the appropriate field of the indexed hash table slot is scheduled to be executed once the read completes. Note that the read may incur a TLB miss and last up to about a thousand instructions; on a superscalar processor this initiating and scheduling of the read and write is done by executing the read and write instructions, but because of how the overall algorithm is structured, they have no dependencies with other code or atomic instructions, and thus can execute fully in parallel with other instructions. A superscalar processor will automatically delay the write instruction until the read completes, as a dependency exists between them. In a custom logic implementation or a specialized processor, this scheduling could be implemented using a state machine or other suitable logic structures. As an alternative, the read could be initiated already while the CAS instruction is running, allowing more parallelism.
[0066] Execution then continues with ( 405 ) to count the added item and ( 406 ) to check whether the hash table is now too full. If it is too full, the condition may be remedied by switching, expanding, requesting immediate garbage collection, or other suitable means. The code for these actions is denoted by ( 114 ) in FIG. 1 .
[0067] In case the hash table is switched, a new hash table is allocated or taken from e.g. a list, and a pointer to the current hash table (‘ht’) is atomically replaced, e.g. using a compare-and-swap instruction. Multiple threads may try to switch the hash table simultaneously, but the compare-and-swap instruction is used to detect if it has already been switched, so that only one thread can successfully switch it at any given time. If the compare-and-swap instruction indicates that it was already switched by another thread, the newly allocated hash table can be freed or e.g. put back on a freelist, and the slow path operation restarted.
[0068] In case the hash table is expanded, any known or future lock-free hash table expansion method may be used. It should, however, be noted that making a lock-free hash table expandable typically incurs extra overhead, and it may be desirable to avoid such overhead in a write barrier, which is highly performance-critical and whose set of operations and their frequency distribution differs significantly from that typical in general-purpose hash table designs. Expanding (resizing) the hash table is shown as ( 407 ) (though the label should be interpreted as including any method for remedying the too full condition).
[0069] The initial size of the hash table may be computed from system parameters or loaded from a file, and its size may be dynamically adjusted after at least some evacuation pauses at run time to reduce the number of hash table expansions, which are fairly expensive operations, and to reduce the cost of future iterations. The system can collect smoothed statistics of the number of writes performed by the application between evacuation pauses or per a time period, and adjust the hash table size accordingly. Alternatively, it may be made large enough to contain the number of writes that occurred between the previous pair of evacuation pauses. Its size may also be reduced.
[0070] In the switching method, not all hash tables need to be of the same size. A preferable approach is to always make the next hash table twice the size of the previous hash table, which keeps the number of hash tables small in all situations.
[0071] In case immediate garbage collection is requested, the write barrier would call the garbage collector (for just processing the write barrier buffers, for doing an incremental evacuation pause, or at the extreme doing a full GC). This would require that the write barrier be a valid GC point in the architecture (see e.g. O. Agesen: GC Points in a Threaded Environment, Sun Microsystems report SMLI TR-98-70, 1998), which is the case on many architectures. The garbage collector would also need to treat registers used by the write barrier implementation as program registers and update any values and pointers contained therein as appropriate (and well known in the art).
[0072] The garbage collection may also be requested to start soon after completing the write barrier (e.g. when the next GC point is entered), probably avoiding the need to actually remedy a too full condition, though it may not always be avoided. The request is preferably done by setting a global variable. In this case the write barrier need not be a GC point.
[0073] Checking whether the hash table has become too full could be based on a number of approaches. First, one should note that the check could alternatively be placed anywhere in the loop through ( 411 ). In the loop, a possible criterion would be the number of iterations through the loop, which is indicative of the level to which the hash table has been filled. Another possible criteria is comparing the number of items added to the hash table against a limit based on the current size of the hash table ( 406 ), and having a global counter indicate how many items have been added (the counter itself updated atomically, using e.g. a locked increment or a compare-and-swap instruction, or any other known method) ( 405 ). A further possible approach is to generate a random number using a thread-local seed at ( 405 ), compare the random number against a constant, and perform any of the operations discussed above for ( 405 ) if the random number is small (or large) enough, the constant controlling the probability. Other methods are also possible.
[0074] The preferred mode is to count the number of times the loop has been iterated through ( 411 ) using a local variable or register, and if the count exceeds a limit, use the switching method.
[0075] Regardless of how the hash table becoming too full is checked and handled, it may be desirable to cause garbage collection to happen either immediately or very soon if excessively many addresses have been written. The main reason for this is ensuring that the evacuation pause that needs to process the written addresses can complete within its allotted time. Causing the garbage collection to happen may involve e.g. calling the garbage collector directly, setting a flag that causes the garbage collector to be called (e.g. when the application next enters a GC point), by scheduling the garbage collector through a timeout, or any other suitable mechanism. These actions are illustrated by ( 408 ).
[0076] At ( 409 ) we know that the compare-and-swap instruction failed. Such failure indicates that the slot is already in use, containing either the same written address or a different written address. ( 409 ) checks which case it is. If it is the same address, then it is already in the hash table, and the insertion is aborted ( 410 ), typically by returning from the slow path function. Otherwise the slot must already be occupied by another address, and another slot must be tried. ( 411 ) illustrates computing the next address. Many ways of dealing with such conflicts have been discussed in the literature, including linear probing (incrementing the address by one modulo the size of the hash table), double hashing, chaining, etc.
[0077] Since the hash function and bit selection method in the preferred mode yields an index where the entropy of the written address is fairly equally divided among the bits of the index, the size of the hash table can be allowed to be a power of two (rather than using the more conventional modulo prime number mixing which prefers prime sized hash tables). The size of the hash table being a power of two allows faster bit selection (bitwise-and instead of modulo), and also allows faster incrementing, as the modulo in the increment can be computed using a bitwise-and instruction in ( 412 ) (basically, ‘idx=(idx+1) & (size−1)’), which is faster than either a modulo or a conditional assignment. Both ( 411 ) and ( 412 ) can also be computed in parallel with ( 401 ), overlapping the CAS instruction on a superscalar processor, at essentially zero cost, which may justify computing them every time, even though the result is rarely needed.
[0078] At ( 413 ) the slow path of the write barrier is complete, after which the actual new value of the written memory address should be stored. It should, however, be noted that the read and write performed in ( 403 ) and ( 404 ) may still continue for hundreds of instructions after the write barrier has completed, executing in parallel with other code. This parallelism gives a significant reduction of the overall cost of the write barrier.
[0079] The write barrier buffer hash table is typically iterated when an evacuation pause starts, though it is also possible to predictively start a thread that iterates and/or empties the hash table, similar to the thread for emptying RS buffers in David Detlefs et al: Garbage-First Garbage Collection, ISMM'04, pp. 37-48, ACM, 2004; such a thread might most advantageously be combined with the switching method described above.
[0080] When a single hash table is used, iteration of the hash table is fairly trivial and well known in the art, especially if the iteration can be performed by a single thread. It could also be done in parallel (e.g. by dividing the slots into a set of slot ranges, each processed by a separate thread).
[0081] Iteration is much more complicated when using the switch approach for remedying the too full condition. In that case, multiple hash tables may exist, and the same address may occur multiple times (at most once per hash table, though). Logically the individual hash tables should be combined into a single hash table for iteration purposes, and each address should only be iterated once (and with the oldest old value).
[0082] Such iteration is performed as follows. Two special marker values are used here, the first being the special value discussed earlier (preferably 0), and the second being a different value but invalid address (preferably 1).
iterate over the oldest hash table, and for each found address:
if it is the second special marker, write the first special marker to it query the address from each younger hash table, and if found, write the second special marker to it, freeing it from the younger hash table pass the address (with the old value from the oldest hash table) to the evacuation pause
when the oldest hash table has been iterated, free it (or put it on a list), and repeat these steps until all hash tables have been processed.
[0088] This iteration method can be parallelized by partitioning the oldest hash table and processing each partition by a separate thread. The queries and deletions from younger hash tables can be performed without locking. A known open addressing linear probing hash table query (or lookup or get) algorithm is used for performing the queries (essentially advancing index until a slot with the queried address or the first special marker is found).
[0089] Another task that must be performed, typically during an evacuation pause, is emptying the hash tables. Emptying a hash table typically involves writing a known value (the first special value) to each slot of the hash table. We can optimize the emptying by merging it with the iteration means, writing the first special value to the current slot before or after passing the address to the evacuation pause.
[0090] While this description has mostly assumed that the write barrier buffer (hash table) is emptied by an evacuation pause, it could also be done using one or more separate background threads, similar to the approach in David Detlefs et al: Garbage-First Garbage Collection, ISMM'04, pp. 37-48, ACM, 2004. The intention is not to constrain when the hash table iteration and emptying may occur. In some collectors they may occur in parallel with mutator execution.
[0091] FIG. 5 illustrates the hash table data structure. Rows ( 501 ) illustrate slots, which are preferably data structures comprising at least a written address ( 502 ) and old value ( 503 ) fields. However, it could also contain other data, such as the address (or cell, including tags) of the object containing the written address, a special flag field (such address of the written object would be passed as a argument to the write barrier, and storing it would allow more flexibility for implementing other parts of the garbage collector). It would also be possible to store only part of the address and/or old value (e.g., only the lower order or significant bits), or a transformation of the values, or reorder the fields, without changing the essence of the invention. The number of slots in the hash table is preferably a power of two (2̂N), though other sizes are also possible.
[0092] When used with garbage collectors that do not require access to the old value of the written memory location, that field can naturally be omitted from the hash table, potentially making the hash table slots just memory addresses. Any steps related to loading and saving the old address can be omitted in such implementations.
[0093] FIG. 6 illustrates a computer readable software distribution medium ( 601 ) having computer usable program code means ( 602 ) embodied therein for causing a computer system to perform garbage collection using a write barrier buffer, the computer usable program code means in said computer usable software distribution medium comprising: computer usable program code means for checking if a write must be recorded in a write barrier buffer; computer usable program code means for computing a hash value from the address of the memory location being written and indexing a hash table using at least some bits of the hash value; computer usable program code means for adding the address of the memory location being written to the hash table using a lock-free hash table insertion operation; computer usable program code means for aborting the insertion if the address of the memory location being written is already in the hash table; computer usable program code means for iterating over addresses stored in the hash table and emptying the hash table. Nowadays Internet-based servers are a commonly used software distribution medium; with such media, the program would be loaded into main memory or local persistent storage using a suitable network protocol, such as the HTTP and various peer-to-peer protocols, rather than e.g. the SCSI, ATA, SATA or USB protocols that are commonly used with local storage systems and optical disk drives, or the iSCSI, CFS or NFS protocols that are commonly used for loading software from media attached to a corporate internal network.
[0094] It should be noted that the write barrier component may be implemented as either software or as hardware. Any number of parts of the garbage collector could be implemented in hardware.
[0095] Clearly many reorderings of the steps in the described algorithms and a number of other transformations on the presented algorithms and structures are possible and available to one skilled in the art, without deviating from the spirit of the invention. | A lock-free write barrier buffer is used to combine multiple writes to identical locations and save old values of written memory locations and to reduce TLB misses compared to card marking. The old value of a written location as well as the address of the header of the written object can be saved, which is not possible with card marking. Scanning the card table and marked pages are eliminated. The method is lock-free, scaling to highly concurrent multiprocessors and multi-core systems. | 6 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to semiconductor integrated circuit devices, and more particularly to a method for integrating self-aligned silicide (SALICIDE) field effect transistors (FETs) for logic circuits with dynamic random access memory (DRAM) having self-aligned contacts and capacitors over bit lines (COBs). The method is particularly useful for integrating (embedding) high-density memory with high-performance logic on the same chip.
(2) Description of the Prior Art
Merged logic and memory circuits are finding extensive use in the electronics industry. These circuits, such as microprocessors, are used in the computer industry for general purpose computing. Merged integrated circuits are also used for application-specific circuits (ASC) in other industries, such as automobiles, toys, communications, the like.
To optimize these merged circuits, it is desirable in the electronics industry to form the FETs for the logic and DRAM circuits having different FET process parameters. For example, it is desirable to use a thin gate oxide for the logic FETs and the peripheral circuits for the DRAMs to increase performance (circuit speed), while it is desirable to use a thicker gate oxide, narrower sidewall spacers, and self-aligned contacts (SACs) for the FET access transistors of the DRAM memory cells because of the higher gate voltage (V g ), and also to achieve high density of memory cells and higher yield. It is desirable to integrate the logic and memory circuits on the same chip by using a process that minimizes manufacturing costs.
One method of forming FETs for logic and memory having two different gate oxide thicknesses is described in U.S. Pat. No. 5,668,035 to Fang et al. However, the polycide gate electrodes are of the same thickness and are etched at the same time on both the logic and memory. The application does not address the ability to make sidewall spacers on separate gate electrodes having different widths on the logic and memory. Further, Fang's method does not include making salicide FETs for logic. Huang in U.S. Pat. No. 5,863,820 teaches a method for integrating DRAMs with self-aligned contacts and salicide FETs for logic on the same chip. However, Huang does not teach a method for making memory and logic FETs having different gate-oxide thicknesses and different sidewall-spacer widths. Yoo in U.S. Pat. No. 5,573,980 describes a method for making silicide contacts self-aligned to FET gate electrodes for static RAM cells but does not address merged memory and logic circuits on the same chip. In U.S. Pat. No. 5,472,892 to Gwen et al., a method is disclosed for using a silicide process in making a floating gate memory device and peripheral transistors on the same chip. Lin in U.S. Pat. No. 5,668,065 describes a method for making simultaneously silicide-based self-aligned contacts and logical interconnections, but does not teach integrating memory and logic circuits on the same chip.
Therefore there is still a need in the semiconductor industry to provide a very manufacturable cost-effective process for making merged integrated circuits having salicide FETs for logic circuits and embedded DRAMs with self-aligned node contacts (SACs).
SUMMARY OF THE INVENTION
It is a principal object of the present invention to provide a method form self-aligned titanium silicide FETs for high performance logic circuits with memory circuits having tungsten silicide gate electrodes and self-aligned capacitor node contacts integrated on the same chip.
It is another object of the present invention to achieve the above objective using different gate oxides in the logic and memory circuits, different sidewall-spacer widths, self-aligned contacts with reduced contact resistance, separate liner layers to optimize the formation of borderless metal contacts and self-aligned contacts, and to allow different lightly doped drains in the logic and memory circuits to minimize short-channel effects.
Still another object of this invention is to achieve these objectives without increasing the number of photoresist masking steps, without compromising logic performance and without adding to DRAM cost.
The method for making these merged integrated circuits having self-aligned silicide (salicide) FETs integrated with dynamic random access memory (DRAM) circuits, is now briefly described.
The method begins by providing a semiconductor substrate. Typically the substrate is a P - doped single-crystal silicon having a <100> crystallographic orientation. A field oxide is formed using shallow trench isolation (STI) to surround and electrically isolate device areas in logic regions and DRAM regions on the substrate. A thin first gate oxide is formed on the device areas. An undoped first polysilicon layer is deposited by low-pressure chemical vapor deposition (LPCVD) on the substrate. A first insulating layer, such as silicon oxide (SiO 2 ), is deposited on the first polysilicon layer. The first insulating layer and the first polysilicon layer are removed over the memory region using a photoresist mask and plasma etching. A second gate oxide is formed on the device areas in the memory region. An N doped second polysilicon layer and an upper tungsten metal silicide layer are deposited to form a first polycide layer. Next, a silicon nitride (Si 3 N 4 ) hard-mask layer is deposited on the silicide layer. A photoresist mask and anisotropic etching are used to pattern the hard-mask layer and the first polycide layer to form gate electrodes for DRAMs in the memory region device areas, while the logic region is protected from etching. Lightly N doped first source/drain areas are formed adjacent to the DRAM gate electrodes by implanting phosphorus ions (P 31 ). A conformal Si 3 N 4 layer is deposited and etched back to form insulating sidewall spacers on the gate electrodes. A thin conformal Si 3 N 4 liner layer is deposited. A second insulating layer, such as SiO 2 or a borophosphosilicate glass (BPSG), is deposited to form an interpolysilicon oxide-1 (IPO-1) layer. The second insulating layer is chemically-mechanically polished back to the hard-mask layer over the logic region, and concurrently a planar second insulating layer is formed over the memory region. The Si 3 N 4 hard-mask layer, the first polycide layer and the first insulating layer are removed over the logic region by etching, while the second insulating layer protects the memory region. The undoped first polysilicon layer is patterned to form FET gate electrodes in the device areas in the logic region. Lightly doped source/drain (LDD) areas are formed by ion implanting arsenic ions (As 75 ) adjacent to the gate electrodes in the logic region. A conformal Si 3 N 4 layer is deposited and anisotropically etched back to form insulating sidewall spacers on the gate electrodes in the logic region. A third ion implantation is used to form second source/drain contact areas adjacent to the sidewall spacers on the gate electrodes in the logic region, and concurrently to dope the undoped polysilicon gate electrodes. The salicide FETs are now formed by depositing a conformal titanium metal layer and annealing to selectively form a titanium silicide on the silicon surface of the second source/drain areas and on the doped polysilicon gate electrodes. The unreacted titanium metal is selectively removed from the insulating sidewall spacers and other insulating surfaces on the substrate, thereby forming salicide FETs. Next, a thin blanket silicon oxynitride (SiON) etch-stop layer is deposited which is used in subsequent processing for etching borderless metal contact openings. A third insulating layer, such as BPSG, is deposited and chem-mech polished back to the second insulating layer over the memory region to form a globally planar surface. First contact openings are then etched in the second insulating layer and are filled with a doped polysilicon layer which is then etched or polished back to form polysilicon bit-line plugs and polysilicon capacitor node plugs. The openings are etched extending over the gate electrodes in the memory region to form self-aligned polysilicon contacts. A fourth insulating layer, such as SiO 2 or BPSG, is deposited and second contact openings are etched to the polysilicon bit-line plugs. A second polycide layer is deposited and patterned to form the bit lines. A fifth insulating layer is deposited to complete a second interpolysilicon oxide (IPO-2) layer. Third contact openings are etched in the fifth insulating layer and are filled with a doped polysilicon to form electrical contacts to the polysilicon capacitor node plugs. Next, a sequence of process steps is used to form a stacked capacitor over the electrical contacts. The stacked capacitors having increased capacitance can be formed as commonly practiced in the industry to make fin-shaped, crown-shaped, cylindrical, and the like capacitors. Typically, the capacitor consists of a bottom electrode formed from a patterned polysilicon layer, a thin interlevel dielectric layer, and a top electrode formed from another doped polysilicon layer. A sixth insulating layer is deposited and planarized over the stacked capacitors. Fourth contact openings are etched in the insulating layers to the first polycide layer in the memory region, and concurrently openings are etched to the thin etch-stop layer over the metal silicide on the second source/drain areas in the logic region. The etch-stop layer is removed in the fourth openings, and the fourth contact openings are then filled with metal to form metal contacts. A low-resistivity metal layer, such as aluminum/copper (Al/Cu) is deposited and patterned to form first metal interconnections. An interlevel dielectric (ILD) layer is deposited, and fifth contact openings are etched and filled with metal to form the next level of metal interconnections. The process for forming the first level of interconnections is then repeated to complete the wiring of the merged integrated circuit.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of this invention are best understood with reference to the attached drawings in the figures and the embodiment that follows.
FIGS. 1 through 9 are schematic cross-sectional views showing the sequence of process steps for making merged integrated circuits having salicide FETs for logic circuits with embedded DRAM circuits.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The method for making these merged integrated circuits having logic circuits with embedded DRAMs is now described in detail. The logic and DRAM FETs are formed separately on a substrate during processing. Therefore the FET gate oxides, sidewall spacers and ion implantation can be individually optimized for the logic and memory circuits to maximize the overall circuit performance. The process is described for making only N-channel FETs in the logic circuits to simplify the drawings and discussion. However, it should be also be well understood by one skilled in the art that by including additional process steps, in addition to those described in this embodiment, other types of devices can be included on the logic and DRAM circuits. For example, by including N-well and P-well regions on a substrate, P-channel and-channel FETs can be provided from which Complementary Metal-Oxide-Semiconductor (CMOS) circuits can be formed. Also the salicide FETs formed in the logic portion of the chip can be used for the peripheral read/write circuits on the DRAM portion of the chip to further improve performance.
Referring now to FIG. 1, the method begins by providing a semiconductor substrate 10, a portion of which is shown in the Figs. The figures show the substrate having a region L for logic circuits and a region M for DRAM circuits. Typically the substrate 10 is a P - doped single-crystal silicon having a <100>crystallographic orientation. Field oxide regions 12 are formed surrounding and electrically isolating the device areas in both regions L and M. For advanced high-density circuits the preferred field oxide 12 is a Shallow Trench Isolation (STI), as is commonly practiced in the semiconductor industry. Generally the STI is formed by etching trenches in the field oxide areas on the substrate to a depth of between about 2500 and 4000 Angstroms. After forming a thin thermal oxide in the trenches, the trenches are filled with an insulating material such as silicon oxide (SiO 2 ), and are made planar with the surface of the substrate 10, for example, by using a planarizing etch-back or chemical/mechanical polishing (CMP).
Still referring to FIG. 1, a thin first gate oxide 14 is formed on the device areas, for example, by thermal oxidation. Since the first gate oxide 14 is used for the logic region L, the oxide is grown to a thickness of only about 20 to 100 Angstroms to improve FET performance. Next, an undoped first polysilicon layer 16 is deposited by low-pressure chemical vapor deposition (LPCVD) using, for example, silane (SiH 4 ) as the reactant. The thickness of the undoped polysilicon layer 16 is between about 1000 and 1500 Angstroms. A first insulating layer 18, such as silicon oxide (SiO 2 ), is deposited by LPCVD on the undoped first polysilicon layer 16 using tetraethosiloxane (TEOS) as the reactant gas, and the oxide is deposited to a thickness of about 200 Angstroms or less. Layer 18 is optional.
Referring to FIG. 2, conventional photolithographic techniques and plasma etching are used to remove the first insulating layer 18 and the undoped first polysilicon layer 16 over the memory region M, while the photoresist mask 20 protects region L from etching. Next, the remaining first gate oxide layer 14 is removed from the device areas in region M, for example, using a dilute hydrofluoric acid etch.
Referring to FIG. 3, a second gate oxide 24 is formed on the device areas in the memory region M for the access transistors. The second gate oxide 24 is formed preferably by thermal oxidation to a thickness of between about 80 and 100 Angstroms. Next, an N doped second polysilicon layer 25 and an upper tungsten metal silicide layer 26 are deposited to form a first polycide layer. The second polysilicon layer 25 is deposited by LPCVD using, for example, SiH 4 as the reactant gas, and is deposited to a thickness of between about 1000 and 1500 Angstroms. Layer 25 is doped with arsenic or phosphorus, either by ion implantation or in-situ during deposition, to a concentration of between about 1.0 E 19 and 1.0 E 21 atoms/cm 3 . The tungsten silicide (WSi x ) layer 26 is deposited by LPCVD using tungsten hexafluoride (WF 6 ) and SiH 4 as the reactant gases, and is deposited to a thickness of between about 1000 and 1500 Angstroms. Next, an optional SiO 2 layer 28, about 300 Angstroms thick, can be deposited as a stress-release and adhesion layer. A Si 3 N 4 hard-mask layer 30 is then deposited by LPCVD using dichlorosilane (SiCl 2 H 2 ) and ammonia (NH 3 ) as the reactant gases. The Si 3 N 4 layer 30 is deposited to a thickness of between about 1500 and 2000 Angstroms.
Referring to FIG. 4, conventional photolithographic techniques using a photoresist mask 32 and anisotropic etching are used to pattern the hard-mask layer 30 and the first polycide layer (26 and 25) to form gate electrodes for the access transistors in the memory cell region M for the DRAM devices. The photoresist mask 32 is also used to protect the logic region L during etching. The photoresist mask 32 is then removed by plasma ashing in oxygen (O 2 ) and/or wet stripping. Lightly N doped first source/drain areas 19(N) are formed adjacent to the gate electrodes in the memory region M by implanting phosphorus ions (P 31 ). The phosphorus is preferably implanted at a dose of between about 1.0 E 13 and 1.0 E 15 atoms/cm 2 , and more specifically at a dose of 2.0 E 13 atoms/cm 2 , and at an implant energy of about 40 KeV.
Referring to FIG. 5, a conformal Si 3 N 4 layer 34 is deposited and anisotropically etched back to form insulating sidewall spacers 34 on the gate electrodes for the DRAMs. The Si 3 N 4 layer 34 can be deposited to a thickness to optimize the DRAM FETs. Preferably the Si 3 N 4 layer 34 is deposited to a thickness of between about 400 and 2000 Angstroms. The Si 3 N 4 layer 34 is then anisotropically etched back using reactive ion etching (RIE) to form sidewall spacers 34 that have a width of 500 Angstroms or less. Alternatively, layer 34 can be silicon oxynitride (SiON). After forming the sidewall spacers 34, a thin conformal Si 3 N 4 liner layer (not shown) is deposited to a thickness of 200 Angstroms or less to protect the substrate when self-aligned contacts for the DRAM cells are etched in a subsequent process step.
Still referring to FIG. 5, a second insulating layer 36 is deposited to form an interpolysilicon oxide-1 (IPO-1) layer. Layer 36 is preferably a SiO 2 deposited by LPCVD using TEOS and ozone as the reactant gases. If layer 36 is a borophosphosilicate glass (BPSG) then boron and phosphorus dopant gases are included during deposition. Second insulating layer 36 is deposited to a thickness that is greater than the height H of the multilayer (layers 16, 18, 25, 26, 28, and 30) as shown in FIG. 5, and more specifically to a thickness of between about 6000 and 8000 Angstroms.
Referring now to FIG. 6, the second insulating layer 36 is chemically-mechanically polished back to the hard-mask layer 30 over the logic region L, and results in a planar second insulating layer 36 over the memory region M. The polishing of layer 34 can be carried out using a polishing tool and polishing slurry as commonly practiced in the industry.
Referring to FIG. 7, the Si 3 N 4 hard-mask layer 30, the SiO 2 layer 28, the first polycide layer (26 and 25), and the first insulating layer 18 are removed over the logic region L by etching, while the second insulating layer 36 protects the memory region M. The hard-mask layer 30 is removed preferably by etching in phosphoric acid (H 3 PO 4 ), and the WSi x layer 26 and the polysilicon layer 25 are removed by plasma etching using an etchant gas containing chlorine (Cl 2 ).
Still referring to FIG. 7, the salicide FETs for the logic circuits are now formed in the logic region L. Conventional photolithographic techniques and anisotropic etching are used to pattern the exposed undoped first polysilicon layer 16 to form the FET gate electrodes. The etching is carried out in a HDP etcher using an etchant gas containing Cl 2 that etches the polysilicon selectively to the underlying first gate oxide 14. Next, lightly doped source/drain (LDD) areas 37(N - ) are formed by ion implanting arsenic ions (As 75 ) adjacent to the gate electrodes in the logic region L. Then a conformal Si 3 N 4 layer 38 is deposited and anisotropically etched back to form insulating sidewall spacers 38 on the gate electrodes in the logic region L. Preferably the Si 3 N 4 layer 38 is deposited to a thickness of about 1000 Angstroms or less and is etched back to form sidewall spacers having a width of about 1000 Angstroms or less. Since these sidewall spacers 38 and the first gate oxide are formed separately from the sidewall spacers 34 and second gate oxide 24 in the memory region M, the performance (speed) of the logic FETs can be optimized. A third ion implantation is used to form second source/drain contact areas 39(N + ) adjacent to the sidewall spacers 38 on the gate electrodes in the logic region L, and concurrently this ion implantation is used to dope the undoped polysilicon gate electrodes (layer 16). Preferably the LDD areas 37 are doped by implanting with As 75 ions to a concentration of between about 1.0 E 18 and 1.0 E 19 atoms/cm 3 and the contact areas 39 are also doped with As 75 ions to a concentration of between about 1.0 E 19 and 1.0 E 20 atoms/cm 3 .
Still referring to FIG. 7, the salicide FETs are now completed, as commonly practiced in the industry. The substrate is etched in a dilute HF for a short time (less than 20 seconds) to remove any oxide on the source/drain contacts 39. Then a conformal titanium (Ti) metal layer is deposited and annealed to selectively form a titanium silicide (TiSi x ) 40 on the exposed silicon surface of the second source/drain areas 39(N + ) and on the doped polysilicon gate electrodes (doped layer 16) in the logic region L. Typically the Ti is deposited by sputter deposition to a thickness of between about 200 and 400 Angstroms. The Ti is reacted by rapid thermal anneal at a temperature of between about 500 and 700° C. for about 30 seconds. The unreacted Ti metal on the oxide surfaces, which include the sidewall spacers 38, is selectively removed by etching in a solution of NH 4 OH and H 2 O 2 . After removing the unreacted Ti, a second rapid thermal anneal is carried out at a temperature of between about 700 and 900° C. for about 30 seconds to complete the reaction and to reduce the sheet resistance of the TiSi x 40.
Referring to FIG. 8, a thin blanket silicon oxynitride (SiON) etch-stop layer 42 is deposited which is used in subsequent processing for etching borderless metal contact openings. Layer 42 is deposited by LPCVD using, for example SiH 4 , nitrous oxide (N 2 O), and NH 3 as the reactant gases. The oxynitride layer 42 is deposited to a thickness of between about 200 and 500 Angstroms. Continuing, a third insulating layer 44, such as SiO 2 , is deposited by high-density plasma CVD at a relatively low temperature of less than about 600° C. The third insulating layer 44 is deposited to a thickness that is greater than the height of the polished back second insulating layer 36, and more specifically to a thickness of about 6000 to 8000 Angstroms. Layer 44 is then chem-mech polished back to the second insulating layer 36 over the memory region M to form a globally planar surface 44, as shown in FIG. 8. Alternatively, a doped oxide such as BPSG can be used as the third insulating layer 44.
Still referring to FIG. 8, using conventional photolithographic techniques and anisotropic plasma etching, first contact openings 2 are selectively etched in the second insulating layer 36 to the Si 3 N 4 liner layer (not shown). The openings 2 are etched extending over the gate electrodes in the memory region M to form self-aligned contact openings. After removing the thin (200 Angstroms thick) liner layer by a brief plasma etch using a fluorine-containing gas and O 2 , the openings 2 are filled by depositing a polysilicon layer 46 that is in-situ doped with phosphorus to a concentration of between about 1.0 E 19 and 1.0 E 21 atoms/cm 3 . Layer 46 is then etched or polished back to form polysilicon bit-line plugs 46A and polysilicon capacitor node plugs 46B.
Referring to FIG. 9, a fourth insulating layer 48, such as SiO 2 or BPSG, is deposited by CVD to a thickness of between about 1000 and 1500 Angstroms. Second contact openings 4 are etched anisotropically in the fourth insulating layer 48 to the polysilicon bit-line plugs 46A. A second polycide layer, consisting of a doped polysilicon layer 50 and a tungsten silicide layer 52, is deposited and patterned to form the polycide bit lines 53. A fifth insulating layer 54, is deposited to complete a second interpolysilicon oxide (IPO-2) layer. Layer 54 is SiO 2 or BPSG, and is deposited by CVD to a thickness of between about 2000 and 4000 Angstroms over the bit lines 53. Third contact openings 6 are etched in the fifth insulating 54 layer to the polysilicon capacitor node plugs 46B. A doped polysilicon layer 56 is deposited sufficiently thick to fill the openings 6, and is polished back to form electrical contacts, also labeled 56, to the node plugs 46B. Next, a sequence of process steps is used to form a stacked capacitor over and contacting the electrical contacts 56. The stacked capacitors having increased capacitance can be formed as commonly practiced in the industry to make fin-shaped, crown-shaped, cylindrical, or other high-capacitance capacitors. Typically, the capacitor consists of a polysilicon bottom electrode 58, a thin interlevel dielectric layer 60, and a polysilicon top electrode 62. A sixth insulating layer 64 is deposited and planarized over the stacked capacitors. Fourth contact openings 8 are anisotropically etched in the insulating layers 64, 54, 48, 36, and 30 to the first polycide layer (25 and 26) in the memory region M, and concurrently openings are etched to the thin SiON etch-stop layer 42 over the titanium silicide layer 40 on the second source/drain areas 39 in the logic region L. The SiON etch-stop layer 42 is removed in the fourth openings 8. The contact openings 8 are then filled by depositing a metal and etching back to form metal contacts 66. The metal contacts 66 can be formed from tungsten, aluminum/copper, or copper.
Continuing with FIG. 9, a low-resistivity metal layer 68, such as Al/Cu, is deposited to a thickness of between about 4000 and 6000 Angstroms, and is patterned to form first metal interconnections. An interlevel dielectric (ILD) layer 70, such as SiO 2 , is deposited by high-density plasma CVD using TEOS as the reactant gas. Next, fifth contact openings are etched and filled with metal to form the next level of metal plugs 72 for the next level of metal interconnections (not shown).
The process for forming the first level of interconnections is then repeated to complete the wiring of the merged integrated circuit.
While the invention has been particularly shown and described with reference to the preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention. | A method for fabricating merged logic and DRAM integrated circuits (ICs) is achieved. An undoped polysilicon layer is deposited and protected over the logic region while a first polycide layer is deposited and patterned to form DRAM gate electrodes in the memory region. DRAM gate electrodes are then protected with an insulating layer and the undoped polysilicon is exposed and patterned to form logic gate electrodes. The source/drain areas and undoped polysilicon are doped by implanting and a titanium metal is deposited and annealed to form salicide FETs for logic circuits. This allows the IC to be fabricated having different FET gate-oxide thicknesses for the logic and memory circuits, different sidewall-spacer widths, self-aligned contacts, separate liner layers to optimize the formation of borderless metal contacts with reduced contact resistance, and different lightly doped drains in the logic and memory circuits to maximize the overall circuit performance. The merged integrated circuit is now completed to the first level of metal interconnections by forming bit lines and capacitors which are insulated, by forming metal contacts through the insulation, and by patterning a metal layer to form the first level of metal interconnections. | 7 |
The present application is a divisional of U.S. patent application Ser. No. 11/806,221, filed on May 30, 2007, currently pending, which claims priority, pursuant to 35 U.S.C. §119, to U.S. Provisional Patent Application No. 60/809,046 filed May 30, 2006, the entire contents of each application is incorporated herein by reference.
FIELD OF THE DISCLOSURE
The present disclosure relates to arrangements, compositions, as well as design and fabrication techniques relating to munitions.
BACKGROUND OF THE INVENTION
In the discussion of the state of the art that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicant expressly reserves the right to demonstrate that such structures and/or methods do not qualify as prior art.
A conventional blast-frag warhead inflicts damage by two primary methods. The first is the overpressure generated from the detonation of an explosive fill. The second is the formation and acceleration of metal fragments from the warhead case caused by the detonation of an explosive. Different targets exhibit varying degrees of vulnerability to these damage mechanisms. Materiel is more vulnerable to fragments and structures are more vulnerable to blast overpressure. Personnel are vulnerable to both. In light of this, general purpose bombs are usually of the blast-frag variety to ensure that a large target set can be held at risk with a single weapon.
In general, the damage radius for fragmentation is considerably larger than that for blast. Blast damage drops off as a function of distance to the 3rd power. The addition of precision delivery with blast-frag warheads enables a significant weapon system lethality overmatch against many targets. This overmatch has driven our adversaries to attempt to seek cover in civilian populations where our rules of engagement limit our ability to engage them. The rules of engagement are driven by the political motivation to limit collateral damage. Collateral damage is the unintended damage or destruction of life or property near a target. Thus a general purpose warhead that could limit collateral damage without compromising probability of kill would be highly advantageous.
Others have tried to create low collateral damage warheads by eliminating fragment formation by replacing a metal case with a fiber reinforced plastic one. The elimination of the fragments results in a warhead with a primarily blast damage mechanism. However, the permanent elimination of fragments limits the target set against which the weapon is useful and in essence a niche weapon. It increases the logistic trail and mission loadout complexity.
SUMMARY OF THE INVENTION
The disclosed invention includes methods and constructions for selecting between a blast or blast-frag operational mode for a warhead. The selectability is achieved, at least in part, by using a meltable or phase-changeable material in the warhead case. For example, within the case, included as a composite structure or as a discreet layer(s), is a reactive material capable of releasing sufficient thermal energy to melt the meltable material of the case. The case is filled with an explosive payload.
In the blast-frag mode, the warhead is detonated as a conventional warhead, and the metal within the case is fragmented or dispersed naturally or along preformed scribes. In the blast-only mode, a fuze or other initiating component is used to ignite the reactive material in the case. The heat released from the reactive material induces a phase transformation (e.g., melting) of the fragments within the case. Immediately following this reaction the high explosive is initiated allowing the blast to propagate through the molten material.
According to the principles of the present invention, the above-described selectability of the mode of operation of a munition allows the weapon to be used against a broad target set like a general purpose bomb, but when the need arises for reduced collateral effects, the fragments can be selectively eliminated.
According to one aspect, the present invention provides a munition comprising: a casing, the casing comprising a material comprising (i) a meltable or phase-changing material, and (ii) an energetic material; an explosive payload contained within the casing; and a fuze arrangement, the fuze arrangement comprising a main fuze configured and arranged to ignite the high explosive, and at least one secondary fuze configured and arranged to initiate melting or a phase change of the casing material.
According to a further aspect, the present invention provides A method of selectively altering the mode of operation of a munition, the method comprising: forming a casing, the casing comprising a material comprising (i) a meltable or phase-changing, and (ii) an energetic material; introducing an explosive payload into the casing; providing a fuze arrangement comprising a main fuze and at least one secondary fuze configured and arranged to initiate melting or a phase change of the casing material; and selectively activating the main fuze and the at least one secondary fuze in a manner that provides at least a first and a second mode of operation, the first mode of operation comprising blast coupled with fragmentation effects, and the second mode of operation comprising mainly blast effects.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The following detailed description of preferred embodiments can be read in connection with the accompanying drawings in which like numerals designate like elements and in which:
FIG. 1 is a longitudinal sectional illustration of a munition formed according to the principles of the present invention.
FIG. 2 is a cross-sectional view taken along line 2 - 2 of FIG. 1 .
FIG. 3 is a schematic illustration of different modes of operation of a munition according to the principles of the present invention.
DETAILED DESCRIPTION
FIGS. 1-2 illustrates an exemplary munition 10 formed according to one embodiment of the present invention. As illustrated, the munition 10 may be in form of a warhead comprising a casing 12 carrying an explosive payload 20 . The shape of the casing 12 is not limited to the illustrated embodiment, and may have any suitable geometry and/or size. The casing 12 may optionally include an inner and/or outer liner or shield 14 and/or 16 , respectively. The liner(s) or shield(s) may be provided as a thermal shield. The liner(s) and/or shield(s) can be formed from any suitable material(s). By way of non-limiting example, the shields can be formed from a thermoplastic. Thermoplastics such as polytetrafluoroethylene (PTFE) or polyetheretherketone (PEEK) can be utilized. The linear(s) and/or shield(s) 14 , 16 serve to, at least in part, prevent the transfer of thermal energy to the payload 20 of a magnitude that could cause unwanted detonation thereof.
The main component of the casing 12 is a layered or composite material 18 . This material can be composed mainly of two components: (i) a meltable or phase-changing material, and (ii) an energetic material. The two components can be arranged relative to one another in any suitable fashion. For example, the material can comprise a matrix of the meltable or phase-changing material with the energetic material dispersed therein. Alternatively, the material can comprise one or more layers of the meltable or phase-changing and one or more layers of the energetic material.
The meltable or phase-changing material can be formed from any suitable metal or combination of metals and/or alloys. According to one embodiment, the metal comprises an elemental metal or alloy that when combined with the energetic component (or components); the pressure used to compact and densify the structure is of a magnitude below that which would cause auto ignition of the reactive materials. According to a further embodiment, the metal comprises one or more of: bismuth, lead, tin, aluminum, magnesium, titanium, gallium, indium, and alloys thereof. By way of non-limiting example, suitable alloys include (percentages are by mass): 52.2% In/45% Sn/1.8% Zn; 58% Bi/42% Sn; 60% Sn/40% Bi; 95% Bi/5% Sn; 55% Ge; 45% Al; 88.3% Al/11.7% Si; 92.5% Al/7.5% Si; 95% Al/5% Is; Zn 100%; 4% Al/2.5% Cu/0.04% Mg/Bal Zn; and 11% Al/1% Cu/0.025% Mg/Bal Zn. In addition, the metal may optionally include one or more reinforcing elements or additives. Thus, the metal may optionally include one or more of: an organic material, an inorganic material, a metastable intermolecular compound, and/or a hydride. By way of non-limiting example, one suitable additive could be a polymeric material that releases a gas upon thermal decomposition. The composite can also be reinforced by adding one or more of the following organic and/or inorganic reinforcements: continuous fibers, chopped fibers, whiskers, filaments, a structural preform, a woven fibrous material, a dispersed particulate, or a nonwoven fibrous material. The fragmenting composite may also be partially or full encapsulated within a metal jacket to provide strength and explosive launch survivability. Other suitable reinforcements are contemplated.
The energetic material component may comprise any suitable energetic material, which is dispersed within the meltable or phase-changing binder material, or disposed in one or more layer(s) adjacent to the meltable metal. The energetic material may have any suitable morphology (i.e., powder, flake, crystal, etc.) or composition.
The energetic material may comprise a material, or combination of materials, which upon reaction, release enthalpic or work-producing energy. One example of such a reaction is called a “thermite” reaction. Such reactions can be generally characterized as a reaction between a metal oxide and a reducing metal which upon reaction produces a metal, a different oxide, and energy. There are numerous possible metal oxide and reducing metals which can be utilized to form such reaction products. Suitable combinations include but are not limited to, mixtures of aluminum and copper oxide, aluminum and tungsten oxide, magnesium hydride and copper oxide, magnesium hydride and tungsten oxide, tantalum and copper oxide, titanium hydride and copper oxide, and thin films of aluminum and copper oxide. A generalized formula for the stoichiometry of this reaction can be represented as follows:
M x O y +M z =M x +M z O y +Energy
wherein M x O y is any of several possible metal oxides, M z is any of several possible reducing metals, M x is the metal liberated from the original metal oxide, and M z O y is a new metal oxide formed by the reaction. Thus, according to the principles of the present invention, the energetic material 130 may comprise any suitable combination of metal oxide and reducing metal which as described above. For purposes of illustration, suitable metal oxides include: La 2 O 3 , AgO, ThO 2 , SrO, ZrO 2 , UO 2 , BaO, CeO 2 , B 2 O 3 , SiO 2 , V 2 O 5 , Ta 2 O 5 , NiO, Ni 2 O 3 , Cr 2 O 3 , MoO 3 , P 2 O 5 , SnO 2 , WO 2 , WO 3 , Fe 3 O 4 , MoO 3 , NiO, CoO, Co 3 O 4 , Sb 2 O 3 , PbO, Fe 2 O 3 , Bi 2 O 3 , MnO 2 Cu 2 O, and CuO. For purposes of illustration, suitable reducing metals include: Al, Zr, Zn, Th, Ca, Mg, U, B, Ce, Be, Ti, Ta, Hf, and La. The reducing metal may also be in the form of an alloy or intermetallic compound of the above. For purposes of illustration, the metal oxide is an oxide of a transition metal. According to another example, the metal oxide is a copper or tungsten oxide. According to another alternative example, the reducing metal comprises aluminum or an aluminum-containing compound.
As noted above, the energetic material component may have any suitable morphology. Thus, the energetic material may comprise a mixture of fine powders of one or more of the above-mentioned metal oxides and one or more of the reducing metals. This mixture of powders may be dispersed in the metal, which can act like a binder. According to certain embodiments, the metal acts as a partial or complete source of metal fuel for the energetic, or thermite, reaction.
The energetic material may be in the form of a thin film having at least one layer of any of the aforementioned reducing metals and at least one layer of any of the aforementioned metal oxides. The thickness of the alternating layers can vary, and can be selected to impart desirable properties to the energetic material. For purposes of illustration, the thickness of layers and can be about 10 to about 1000 nm. The layers may be formed by any suitable technique, such as chemical or physical deposition, vacuum deposition, sputtering (e.g., magnetron sputtering), or any other suitable thin film deposition technique. Each layer of reducing metal present in the thin-film can be formed from the same metal. Alternatively, the various layers of reducing metal can be composed of different metals, thereby producing a multilayer structure having a plurality of different reducing metals contained therein. Similarly, each layer of metal oxide can be formed from the same metal oxide. Alternatively, the various layers of metal oxide can be composed of different oxides, thereby producing a multilayer structure having different metal oxides contained therein. The ability to vary the composition of the reducing metals and/or metal oxides contained in the thin-film structure advantageously increases the ability to tailor the properties of the detonable energetic material, and thus the properties of the casing material.
The casing 12 of the present invention can be formed according to any suitable method or technique.
Generally speaking, a suitable method for forming a casing according to the present invention includes forming an energetic material, combining the energetic material with a meltable or phase-changing material to form a mixture, and shaping the mixture to form a composite structural component (e.g., casing).
The energetic material can be formed according to any suitable method or technique. For example, when the energetic material is in the form of a thin film, as mentioned above, the thin-film detonable energetic material can be formed as follows. The alternating layers of oxide and reducing metal are deposited on a substrate using a suitable technique, such as vacuum vapor deposition or magnetron sputtering. Other techniques include mechanical rolling and ball milling to produce layered structures that are structurally similar to those produce in vacuum deposition. The deposition or fabrication processes are controlled to provide the desired layer thickness, typically on the order of about 10 to about 1000 nm. The thin-film comprising the above-mentioned alternating layers is then removed form the substrate. Removable can be accomplished by a number of suitable techniques such as photoresist coated substrate lift-off, preferential dissolution of coated substrates, and thermal stock of coating and substrate to cause film delamination. According to one embodiment, the inherent strain at the interface between the substrate and the deposited thin film is such that the thin-film will flake off the substrate with minimal or no effort.
The removed layered material is then reduced in size; preferably, in a manner such that the pieces of thin-film having a reduced size are also substantially uniform. A number of suitable techniques can be utilized to accomplish this. For example, the pieces of thin-film removed from a substrate can be worked to pass them through a screen having a desired mesh size. By way of non-limiting example, a 25-60 size mesh screen can be utilized for this purpose. This accomplishes both objectives of reducing the size of the pieces of thin-film removed from the substrate, and rendering the size of these pieces substantially uniform.
The above-mentioned reduced-size pieces of thin layered film are then combined with metallic matrix or binder material to form a mixture. The metallic binder material can be selected from many of the above-mentioned binder materials. This combination can be accomplished by any suitable technique, such as milling or blending. Additives or additional components can be added to the mixture. As noted above, such additives or additional components may comprise one or more of: an organic material, and inorganic material, a metastable intermolecular compound, and/or a hydride. In addition, one or more reinforcements may also be added. Such reinforcements may include organic and/or inorganic materials in the form of one or more of: continuous fibers, chopped fibers, whiskers, filaments, a structural preform, dispersed particulate, a woven fibrous material, or a nonwoven fibrous material. Optionally, the pieces of layered film, the metallic binder material, the above-mentioned additives and/or the above-mentioned reinforcements can be treated in a manner that functionalizes the surface(s) thereof, thereby promoting wetting of the pieces of thin-film in the matrix of metallic binder. Such treatments are per se known in the art. For example, the particles can be coated with a material that imparts a favorable surface energy thereto.
This mixture can then be shaped thereby forming a structural component having a desired geometrical configuration. The structural component can be shaped by any suitable technique, such as molding or casting, pressing, forging, cold isostatic pressing, hot isostatic pressing. As noted above, the structural component or casing can be provided with any suitable geometry.
As explained above, there are number of potential applications for a structural component according to principles of the present invention. Non-limiting exemplary weapons and/or weapons systems which may incorporate composite structural components formed according to the principles of the present invention include a BLU-109 warhead or other munition such as BLU-109/B, BLU-113, BLU-116, JASSM-1000, J-1000, and the JAST-1000.
As previously noted, one of the advantages of a munition constructed according to the principles of the present invention is that a single weapon can be provided that has a mode of operation that can be selectively changed. Two such selectable alternative modes of operation are illustrated in FIG. 3 . The munition 10 is only schematically illustrated in FIG. 3 , and may take any suitable form. The munition 10 may comprise a casing (e.g., element 12 ; FIGS. 1-2 ) formed at least in part from a meltable or phase-changing energetic material combination as described above (e.g., element 18 ; FIGS. 1-2 ). The munition may also be provided with an inner and/or outer layer or shield, such as heat shields and to provide containment of melted metal in a blast-only mode (e.g., 14 , 16 ; FIGS. 1-2 ). The behavior of the munition 10 is controlled mainly through the selection and operation of the fuze arrangement (e.g., elements 22 , 24 , 26 and 28 ; FIGS. 1-2 ).
As illustrated in FIG. 3 , the mode of operation of the fuze arrangement is selected. According to a first mode, the main fuze is activated which ignites the high explosive contained within the munition. This explosion causes the casing of the munition to fragment along natural or pre-scribed fault lines. The fragments are intended to impact the target. The kinetic energy of the fragments imparts a destructive effect to the target upon impact therewith.
According to a second mode, one or more secondary fuzes are activated, causing the metal of the casing to undergo a phase change (e.g., melt). Subsequently, or simultaneously, the main fuze is activated causing ignition of the high explosive, thereby causing an explosion. However, since the casing has been reduced to a non-solid state, no (or few) solid fragments are produced thereby. Thus, the amount of collateral damage produced by the spreading of and impact of fragments can be greatly reduced, if not eliminated.
All numbers expressing quantities of ingredients, constituents, reaction conditions, and so forth used in the specification are to be understood as being modified in all instances by the term “about”. Notwithstanding that the numerical ranges and parameters setting forth, the broad scope of the subject matter presented herein are approximations, the numerical values set forth are indicated as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from their respective measurement techniques, as evidenced for example, by the standard deviation associated therewith.
Although the present invention has been described in connection with preferred embodiments thereof, it will be appreciated by those skilled in the art that additions, deletions, modifications, and substitutions not specifically described may be made without department from the spirit and scope of the invention as defined in the appended claims. | A munition includes a casing, the casing formed at least in part from a material comprising (i) a meltable or phase-changing material, and (ii) an energetic material; an explosive payload contained within the casing; and a fuze arrangement, the fuze arrangement comprising a main fuze configured and arranged to ignite the high explosive, and at least one secondary fuze configured and arranged to cause the casing material to melt or undergo a phase change. A method of selectively altering the mode of operation of a munition includes: forming a casing, the casing comprising a material comprising (i) a meltable or phase-changing material, and (ii) an energetic material; introducing an explosive payload into the casing; providing a fuze arrangement comprising a main fuse and at least one secondary fuze configured and arranged to cause the casing material to melt or undergo a phase change; and selectively activating the main fuze and the at least one secondary fuze in a manner that provided at least a first and a second mode of operation, the first mode of operation comprising blast coupled with fragmentation effects, and the second mode of operation comprising mainly blast effects. | 5 |
[0001] This application is a continuation of and claims the priority of U.S. patent application Ser. No. 09/228,965, filed Jan. 12, 1999, the entire contents of which are incorporated by reference herein.
FIELD OF THE INVENTION
[0002] This application relates to methods and apparatus for hot chamber die casting of semisolid materials.
BACKGROUND OF THE INVENTION
[0003] Die casting has traditionally been divided into cold chamber processes and hot chamber processes. Hot chamber processes are distinguished by the fact that the injection cylinder is at least partially immersed in the molten metal, and thus is at the same temperature as the molten metal. Hot chamber die casting is widely used for light alloys such as magnesium- and zinc-based alloys, but has not been found to be commercially viable for casting aluminum alloys. These alloys generally have a higher melting temperature, and thus tend to rapidly degrade steel die casters using a hot chamber process.
[0004] Advantages of the hot chamber casting process include higher productivity, reduced scrap and metal losses, reduced die closing pressures, and reduced die wear. Both hot and cold chamber processes, however, suffer from the disadvantage that it is difficult to produce fully sound castings. Liquid metal generally enters the die in a turbulent fashion, entrapping mold gases and forming oxide inclusions in the finished part. Further, solidification shrinkage produces porosity and sometimes tears in the finished casting. It is an object of the present invention to provide a hot-chamber die casting system which minimizes or eliminates these disadvantages.
SUMMARY OF THE INVENTION
[0005] The present invention supplies a hot chamber method of die casting material in a semisolid state. The semisolid material has a high viscosity, which can be controlled by controlling the fraction of solid phase and the morphology of the solid phase. By controlling the viscosity of the melt, turbulence and consequent gas entrapment can be minimized or eliminated. Further, shrinkage is substantially reduced, thereby reducing porosity and hot tearing to form stronger, more reliable castings.
[0006] In one aspect, the invention provides a method of die casting, in which a semisolid composition is held between its liquidus and solidus temperatures, and agitated to prevent the formation of interconnected dendritic networks. The composition forms a slurry of solid particles in liquid, which is pumped into a die by an immersed pump. The material is then cooled to cast it in the die. The material may be, for example, a light alloy such as a magnesium, zinc, or aluminum alloy.
[0007] In another aspect, the invention includes a hot chamber die caster adapted to cast semisolid materials. The die caster includes a container for holding a composition in the semisolid state, and a pump for pumping the semisolid material into a die. Agitation means prevent the formation of dendrites, holding the material in a semisolid slurry state. The agitation means may be, for example, mechanical or electromagnetic. The caster may be used to cast a variety of light alloys, such as magnesium, zinc, and aluminum alloys. The pump may comprise ferrous materials such as stainless steel.
BRIEF DESCRIPTION OF THE DRAWING
[0008] The invention is described with reference to the several figures of the drawing, in which,
[0009] [0009]FIG. 1 is an illustration of a typical hot chamber die casting machine;
[0010] [0010]FIG. 2 is an illustration of one embodiment of a hot chamber die caster according to the invention; and
[0011] [0011]FIG. 3 is an illustration of another embodiment of a hot chamber die caster according to the invention.
DETAILED DESCRIPTION
[0012] [0012]FIG. 1 shows a typical hot chamber die caster 10 , such as is commonly used for casting of magnesium and zinc alloys. The caster works on a “sump pump” principle, using an immersed piston 12 to force molten metal into the casting chamber 14 .
[0013] A hydraulic cylinder 16 reciprocates the piston 12 , within a piston chamber 17 whose end is connected to a gooseneck chamber 18 leading to the casting chamber 14 . As the piston 12 reaches the top of its stroke, molten metal 20 flows into the piston chamber 17 and the gooseneck chamber 18 through an aperture 22 . When the piston 12 then moves down into the chamber 18 , it seals the aperture 22 and forces molten metal into the casting chamber 14 . The casting chamber 14 is defined by two mold halves 24 and 26 . Once the molten metal 20 in the casting chamber 14 has solidified, mold half 26 is moved to release the cast part. The mold is then closed and another cycle of the system can be performed. The gooseneck 18 and cylinder head 16 are thus continuously exposed to molten metal in this process.
[0014] The semisolid (or rheocasting) process was discovered about twenty years ago in the laboratory of one of the present inventors. It was found that mechanical stirring of a material between the liquidus and solidus temperatures could break up dendrites, forming a slurry of spheroidized solid particles in liquid. The viscosity of the material can be set to a value in the range of 10 −1 -10 8 poise, simply by controlling the stirring rate. Detailed descriptions of semisolid processing techniques can be found, for example, in U.S. Pat. Nos. 3,954,455 and 3,948,650 to Flemings, et al., both of which are incorporated herein by reference. Rheocast castings are generally of more uniform strength and of lower porosity than conventional castings.
[0015] The present invention uses semisolid processing to die cast materials using a hot chamber process. FIG. 2 shows a die caster designed to carry out this process. It is similar to the die caster shown in FIG. 1, but includes a mechanical stirrer 28 for agitating semimolten metal 21 . In the embodiment shown, the furnace is provided with a cover 29 and a pressure inlet 30 to aid in forcing semimolten metal 21 through the aperture 22 into the piston chamber 17 . Added pressure is not necessary in standard hot-chamber casting processes, because of the very low viscosity of fully molten metal (typically on the order of 10 −2 poise). The higher viscosity of the semisolid compositions of the present invention may make applied pressure preferable or even essential, depending on the properties of the semisolid composition and of the caster material.
[0016] The optimum applied pressure for any given embodiment depends on the solid fraction of the semisolid metal and the speed with which it is desired to fully fill the piston chamber 17 . It is preferred that die casters according to the invention be able to apply a pressure of at least 30 psi gauge (i.e., 30 psi above atmospheric pressure). If desired, applied pressure and the viscosity of the semisolid metal can be adjusted to provide a relatively high fill rate while minimizing the turbulence of flow into the casting chamber 14 .
[0017] A temperature controller maintains the melt 20 within a relatively narrow temperature range, in order to ensure that it stays between the liquidus and solidus temperatures. For example, the liquidus and solidus temperatures differ by about 120° C. for Mg-8%Al-1%Zn, a common magnesium casting alloy. Known process-control techniques can be used to ensure that the metal temperature and viscosity are kept within acceptable limits.
[0018] [0018]FIG. 3 depicts an embodiment of the die caster related to that of FIG. 2, but using electromagnetic, rather than mechanical, stirring means. A set of coils 32 is provided for heating and stirring the semimolten metal 20 . The use of electromagnetic stirring and heating may simplify the application of pressure, since the coils 32 do not need to be placed within the semimolten metal 21 .
[0019] Hot chamber die casting of semisolid materials offers several advantages. The lower temperatures required may provide reduced energy costs and reduced wear rates for casters, and may expand the list of materials which can be inexpensively die cast by the hot chamber method. Further, the increased viscosity of the melt reduces turbulence as the melt enters the die. Reduced turbulence leads to minimal gas entrapment and thus to a reduced concentration of oxide inclusions. In addition, the shrinkage from the semisolid to the solid state is substantially less than that from the fully liquid to the solid state. Thus, shrinkage porosity and hot tearing are reduced in the present process, allowing simpler and less expensive mold designs to be used.
[0020] Other embodiments of the invention will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims. | A hot chamber method of die casting material in a semisolid state. The semisolid material has a high viscosity, which can be controlled by controlling the fraction of solid phase and the morphology of the solid phase. By controlling the viscosity of the melt, turbulence and consequent gas entrapment can be minimized or eliminated. Further, shrinkage is substantially reduced, thereby reducing porosity and hot tearing to form stronger, more reliable castings. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims priority from U.S. Provisional Application No. 60/323,491 filed Sep. 19, 2001 for “Microwave Ablation Device” by E. Rudie and S. Kluge, and also claims priority from U.S. Provisional Application No. 60/338,250 filed Nov. 2, 2001 for “Microwave Ablation Device” by E. Rudie and S. Kluge.
INCORPORATION BY REFERENCE
[0002] The aforementioned U.S. Provisional Application Nos. 60 / 323 , 491 and 60 / 338 , 250 are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to the field of microwave thermal ablation of tissue.
[0004] Surgical tissue ablation is becoming a popular tool for the treatment of benign and malignant tumors, through laparoscopic and percutaneous techniques, among others. Many ablative technologies have been employed in such treatments, including microwave thermotherapy, which operates to heat tissue above about 45° C. for a period of time sufficient to cause cell death and necrosis in a tissue region of interest. The therapeutic results of microwave ablation have been generally quite positive. However, in order for microwave ablation to become a truly effective tool for the laparoscopic and percutaneous treatment of tumors, an effective microwave antenna must be implemented to efficiently transfer energy to the targeted tissue region so that a precise lesion may be created of proper size and shape to destroy the tumor. In addition, a configuration that improves the achievable depth of heating would be desirable. There is a need in the art for a microwave ablation device having an efficient microwave antenna and a configuration that enables precise and effective ablation of a relatively large targeted region of tissue for the treatment of tumors.
SUMMARY OF THE INVENTION
[0005] The present invention is a tissue ablation device that includes a catheter shaft having an antenna lumen, an impedance-matched microwave antenna carried in the antenna lumen of the catheter shaft, at least one cooling lumen in the catheter shaft around the antenna lumen for circulation of cooling fluid, and a microwave generator operatively coupled to the antenna for energizing the antenna to create a lesion in the targeted tissue around the catheter shaft having a controlled location and size. In an exemplary embodiment, a tip is attached to an end of the catheter shaft for penetrating the tissue targeted for treatment. The device is effective for laparascopic or percutaneous procedures to treat tissues such as the kidney.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] [0006]FIG. 1A is a diagram illustrating the basic configuration for operation of a microwave ablation device according to the present invention.
[0007] [0007]FIG. 1B is a side view of an exemplary embodiment of the microwave ablation device of the present invention.
[0008] [0008]FIG. 2A is a partial section view of a microwave antenna according to the present invention.
[0009] [0009]FIG. 2B is an exploded view of a portion of the microwave antenna shown in FIG. 2A.
[0010] [0010]FIG. 2C is a partial section view of a microwave antenna employing a modified capacitor design according to the present invention.
[0011] [0011]FIG. 3A is a sectional view, and FIG. 3B is a perspective view with a cut-open region shown in section, of an uncooled version of a microwave ablation device according to a first embodiment of the present invention.
[0012] [0012]FIG. 4 is a diagram illustrating a heating pattern obtained during operation of an uncooled microwave ablation device in a tissue phantom.
[0013] [0013]FIG. 5A is a sectional view, and FIG. 5B is a perspective view with a cut-open region shown in section, of a cooled version of a microwave ablation device according to a second embodiment of the present invention.
[0014] [0014]FIG. 6 is a diagram illustrating a heating pattern obtained during operation of a cooled microwave ablation device in a tissue phantom.
[0015] [0015]FIG. 7A is a perspective view, and FIG. 7B is a side view, of an exemplary tip configuration for the microwave ablation device of the present invention.
[0016] [0016]FIG. 8 is a section view of an exemplary handle configuration for the microwave ablation device of the present invention.
[0017] [0017]FIG. 9 is a graph illustrating exemplary thermal history data obtained experimentally from ex vivo operation of a non-cooled microwave probe similar to that shown in FIGS. 3A and 3B.
[0018] [0018]FIG. 10 is a graph illustrating exemplary thermal history data obtained experimentally from ex vivo operation of a cooled microwave probe similar to that shown in FIGS. 5A and 5B.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] [0019]FIG. 1A is a diagram illustrating the basic configuration for operation of microwave ablation device 10 according to the present invention. In one embodiment, microwave ablation device 10 is inserted percutaneously through skin surface 12 into internal tissue that includes targeted tissue region 14 , which may be a tumor or other tissue targeted for necrosis. In other embodiments, microwave ablation device may be inserted laparoscopically through a port, or may be used in an open surgical procedure. Microwave ablation device 10 includes microwave antenna 16 , which is energized when positioned in targeted tissue region 14 to create lesion 18 , which is a region of necrosis that encompasses the entirety of targeted tissue region 14 .
[0020] [0020]FIG. 1B is a side view of an exemplary embodiment of microwave ablation device 10 of the present invention. Microwave ablation device 10 includes handle 11 having cooling fluid input/output ports 11 a and 11 b for communicating cooling fluid with tubes 13 a and 13 b . The device is connectable to a microwave power source through coupling 15 . Microwave antenna 16 is carried at a distal end of microwave ablation device, connected to coaxial cable 17 which receives power from the microwave power source.
[0021] The impedance-matched microwave antenna employed by the present invention is configured as generally described in U.S. Pat. No. 5,300,099 entitled “Gamma Matched, Helical Dipole Microwave Antenna” and assigned to Urologix, Inc. U.S. Pat. No. 5,300,099, which discloses the impedance-matched microwave antenna in the context of a urethral catheter, and which is hereby incorporated by reference in its entirety. A brief description of the antenna is also included in this application for clarity and completeness.
[0022] [0022]FIG. 2A is a partial sectional view of microwave antenna 16 according to the present invention. Antenna 16 is positioned at a distal-most end of shielded coaxial cable 20 . In one exemplary embodiment, cable 20 is a standard RG 178U coaxial cable. In another embodiment, a semi-rigid coaxial cable with a solid outer conductor may be employed to provide additional stiffness. Cable 20 is preferably a non-paramagnetic, MRI-compatible cable, and includes inner conductor 22 , inner insulator 24 , outer conductor 26 , and outer insulator 28 . Outer insulator 28 , outer conductor 26 and inner insulator 24 are stripped away to expose about 3 millimeters of outer conductor 26 , about 1 millimeter of inner insulator 24 and about 1 millimeter of inner conductor 22 . Capacitor 30 includes first end 32 , which is connected to inner conductor 22 (such as by soldering, crimping or welding, for example), and second end 34 , which is connected to antenna 16 . Capacitor 30 serves to counteract a reactive component of antenna 16 , thereby providing a 50 ohm impedance match between antenna 16 and coaxial cable 20 with the microwave generating source connected thereto.
[0023] Although capacitor 30 is shown in FIG. 2A as an axial-type metallized film component, it should be understood that a number of possible capacitor configurations may be used for the impedance matching of antenna 16 . For example, a tubular ceramic capacitor or a discrete section of coaxial cable exhibiting the desired capacitance may be employed, as will be shown in the exemplary embodiment illustrated in FIG. 2C. Other possible capacitor configurations will be apparent to those skilled in the art.
[0024] Tubular extension 36 , which is a hollow section of outer insulator 28 of coaxial cable 20 , or a separate insulative piece approximating the dimensions of outer insulator 28 , is positioned over capacitor 30 and the exposed length of inner insulator 24 and secured by bond 38 . Tubular extension 36 includes hole 40 , which provides an exit for second end 34 of capacitor 30 Wound about outer insulator 28 and tubular extension 36 is flat wire 42 Flat wire 42 is a single piece of flat copper wire with dimensions of about 0.009 inch by about 0.032 inch in cross-section, which provides a relatively large surface area for maximum current flow while minimizing the cross-sectional size of antenna 16 .
[0025] [0025]FIG. 2B is an exploded view of a portion of antenna 16 which shows its helical dipole construction. Generally, the efficiency of any dipole antenna is greatest when the effective electrical length of the antenna is generally one half the wavelength of the radiation emitted in the surrounding medium. Accordingly, a relatively efficient simple dipole antenna, operating at about 915 MHz, would require a physical length of about 8 centimeters which, according to the present invention, would needlessly irradiate and damage healthy tissue outside of the targeted tissue. Furthermore, the physical length of a relatively efficient simple dipole antenna operating at about 915 MHz cannot be varied.
[0026] As shown in FIG. 2B, flat wire 42 is attached to outer conductor 26 at connection point 48 . Flat wire 42 is then wound in a distal direction about outer insulator 28 and in a proximal direction about tubular extension 36 , thereby forming first wire section 44 and second wire section 46 , both of which are of equal length. In one embodiment, first and second wire sections 44 and 46 are each comprised of eight, equally-spaced windings of flat wire 42 The combined length of first and second wire sections 44 and 46 , and hence the overall length of antenna 16 , ranges from about 1 centimeter to about 6 centimeters, and varies according to the length of the area of targeted tissue which requires treatment. In an exemplary embodiment, silicone is applied around coaxial cable 20 , capacitor 30 and flat wire 42 , and a heat-shrink or chemical-shrink tubing is placed around the outside of antenna 16 . After the tubing is shrunk to form a smooth outer surface, the silicone is exposed to ultraviolet radiation in order to cure the silicone and secure all of the components of antenna 16 in place. Other methods of securing antenna 16 in place and providing a smooth outer surface will be apparent to those skilled in the art.
[0027] The helical dipole construction of the present invention allows antenna 16 to range in physical length from about 1 to 6 centimeters, while electrically behaving like an eight centimeter-long simple dipole antenna. In other words, antenna 16 has an effective electrical length generally equal to one half of the wavelength of the radiation emitted in the surrounding medium, independent of its physical length. For purposes of definition, the surrounding medium includes the catheter shaft and the surrounding tissue. This is accomplished by varying the number and pitch of the windings of first and second wire sections 44 and 46 A family of catheters, which contain relatively efficient helical dipole antennas of different physical lengths, permits selection of the antenna best suited for the particular treatment area. In addition, antenna 16 of the present invention is capable of producing a constant heating pattern in tissue, concentrated about antenna 16 , independent of the depth of insertion into the tissue.
[0028] Second end 34 of capacitor 30 , which exits hole 40 , is attached to second wire section 46 at tap point 50 , as shown in FIG. 2A. Tap point 50 is a point at which the resistive component of the combined impedance of first wire section 44 and second wire section 46 matches the characteristic impedance of coaxial cable 20 . The impedance of either first wire section 44 or second wire section 46 is expressed as Z, where Z=R+jX. The impedance Z varies from a low value at connection point 48 (FIG. 2B) to a high value at a point farthest from connection point 48 . There exists a tap position where R is equal to 50 ohms, but an imaginary component, X, is inductive. This inductive component can be canceled by inserting a series capacitance, such as capacitor 30 , which has a value of −jX ohms. This results in an impedance match of 50 ohms real. The resulting method of feeding antenna 16 is commonly called gamma matching. In one embodiment of the present invention, where the physical length of flat wire 42 is about 2.8 cm, tap point 50 is about 3.5 turns from connection point 48 on second wire section 46 . In an exemplary embodiment, the value of capacitor 30 is about 2.7 pF.
[0029] [0029]FIG. 2C is a partial section view of microwave antenna 16 employing a modified capacitor design according to the present invention. Capacitor 30 is realized in this embodiment as a discrete section of coaxial cable exhibiting capacitance that is equal to the desired value for proper impedance matching, as described generally above. In the pictured embodiment, the coaxial cable section forming capacitor 30 is crimped onto inner conductor 22 of coaxial cable 20 and soldered to ensure a strong electrical and mechanical connection.
[0030] The helical dipole construction of antenna 16 achieves a relatively small size, which permits interstitial application. The helical dipole construction is also responsible for three features which enable antenna 16 to achieve greater efficiency than prior known interstitial microwave antennas: good impedance matching, good current carrying capability and an effective electrical length which is generally one half of the wavelength of the radiation emitted in the surrounding medium, independent of the physical length of antenna 16 .
[0031] First, the good impedance match between antenna 16 and inner conductor 22 minimizes reflective losses of antenna 16 , with measured reflective losses of less than 1% in an exemplary embodiment. Second, the use of flat ribbon wire 42 for first wire section 44 and second wire section 46 minimizes resistive losses of antenna 16 by providing a greater surface area upon which current can be carried. Finally, the helical dipole design of antenna 16 has an effective electrical length which is generally one half of the wavelength of the radiation emitted in the surrounding medium, independent of the physical length of antenna 16 . This permits the physical length of antenna 16 to be varied to accommodate varying sizes of lesions while maintaining the same efficient, effective electrical length of antenna 16 .
[0032] The use of an efficient microwave antenna is critical to the ability to focus thermal energy a distance from the antenna within a target volume. An inefficient antenna produces a lesser intensity of microwave radiation within the target volume than desired. The efficient helical dipole design of antenna 16 of the present invention ensures that almost all heat delivered during the treatment is delivered in the form of microwave energy, rather than conductive heat energy.
[0033] In order to create specific lesions sizes and shapes, a microwave ablation device may include only an energy-emitting microwave antenna, or may also include appropriately arranged cooling lumens for circulation of cooling fluid between the microwave antenna and the tissue being heated. A first embodiment of the present invention, described below with respect to FIGS. 3A, 3B and 4 , is an uncooled microwave ablation device, while a second embodiment of the present invention, described below with respect to FIGS. 5A, 5B and 6 , is a cooled microwave ablation device.
[0034] [0034]FIG. 3A is a sectional view, and FIG. 3B is a perspective view with a cut-open region shown in section, of catheter shaft 60 for realizing an uncooled version of a microwave ablation device according to a first embodiment of the present invention. Catheter shaft 60 is generally circular in cross-section, and includes outer wall 62 defining internal antenna lumen 64 . Microwave antenna 16 (FIGS. 2A and 2B) is located in antenna lumen 64 . In an exemplary embodiment, catheter shaft 60 includes a tip (not shown) that enables percutaneous or laparoscopic insertion of catheter shaft 60 into internal tissue, as is known in the art. Catheter shaft 60 has a length of about 30 centimeters (cm) and a diameter of less than 3 millimeters (mm) in an exemplary embodiment. Catheter shaft 60 preferably is sufficiently stiff to perforate soft tissue without buckling. Alternatively, catheter shaft 60 could be composed of a more flexible material if an appropriate introducer is provided to assist the insertion of catheter shaft 60 into tissue, or if a semi-rigid coaxial cable is used for the antenna or a stiffening element is employed to provide additional stiffness.
[0035] Microwave antenna 16 (FIGS. 2A and 2B) utilizes resonance to achieve an efficient and controlled transfer of energy from a transmission line such as a coaxial cable to the targeted tissue. The resonant frequency of microwave antenna 16 depends on the dielectric properties of the material surrounding it, with the highest dependence on the material closest to the antenna. Highly perfused tissue, such as a prostate or a kidney, for example, has a high water content, and water has a high dielectric constant. Therefore, the dielectric properties of these types of tissues are strongly influenced by the water content in the tissue. If water is driven out of the tissue by excessive heating, the dielectric properties of the tissue will change dramatically, causing the resonance of microwave antenna 16 to change to a point where microwave antenna 16 is incapable of continuing to achieve efficient transfer of energy. Therefore, in order to achieve deeper heating of tissue, it is necessary to maintain the temperature of tissue closest to the catheter shaft sufficiently low to maintain its water content and therefore its dielectric properties. In operating an uncooled microwave ablation device, temperatures are highest in the region closest to microwave antenna 16 , and drop off with increasing distance from microwave antenna 16 . The above-described need to keep temperatures adjacent to the catheter below about 100° C. results in a limited depth in which tissue heating capable of cell death (typically greater than about 45-50° C., depending on treatment time) can occur.
[0036] [0036]FIG. 4 is a diagram illustrating a heating pattern obtained during operation of an uncooled microwave ablation device in a tissue phantom, utilizing catheter shaft 60 configured as shown in FIGS. 3A and 3B. The grid lines in FIG. 4 are spaced 1 cm apart. Upon energization of microwave antenna 16 with an input power of 10 Watts for an exposure time of 10 minutes, a heating pattern was observed as shown in FIG. 4. Specifically, 30° C. isotherm 70 , 35° C. isotherm 72 , 40° C. isotherm 74 , 45° C. isotherm 76 and 50° C. isotherm 78 represent the temperature rise above baseline in the heating pattern achieved. During the operation shown in FIG. 4, water on the surface of catheter shaft 60 was just beginning to boil, indicating that the heating pattern achieved is nearly the maximum heating possible without adversely affecting the dielectric constant of the tissue phantom and therefore inhibiting the resonant performance of microwave antenna 16 . The diagram of FIG. 4 shows that the uncooled microwave ablation device is able to achieve temperatures above about 45° C. at a radial distance of about 0.6 cm from the outer surface of catheter shaft 60 on each side, producing a total lesion diameter of about 1.5 cm (since catheter shaft 60 has a diameter of about 0.3 cm). It will be understood by those skilled in the art that other geometrical configurations and variation of the treatment parameters may result in the creation of lesions of larger or smaller sizes.
[0037] [0037]FIG. 5A is a sectional view, and FIG. 5B is a perspective view with a cut-open region shown in section, of catheter shaft 80 for realizing a cooled version of a microwave ablation device according to a second embodiment of the present invention. Catheter shaft 80 is generally circular in cross-section, and includes walls 82 defining internal antenna lumen 84 and cooling lumens 86 , 87 , 88 and 89 . In a first exemplary embodiment, the outer diameter of catheter shaft is about 4.75 millimeters (mm), the diameter of antenna lumen 84 (dimension A) is about 2.54 mm, the thicknesses of cooling lumens 86 , 87 , 88 and 89 (dimension B) are about 0.76 mm, and the wall thickness between antenna lumen 84 and cooling lumens 86 , 87 , 88 and 89 (dimension C), between cooling lumens 86 , 87 , 88 and 89 and catheter shaft 80 (dimension D), and between each of cooling lumens 86 , 87 , 88 and 89 (dimension E) are about 0.12 mm. In a second exemplary embodiment, a smaller catheter is employed, and the outer diameter of catheter shaft is about 3.45 millimeters (mm), the diameter of antenna lumen 84 (dimension A) is about 2.54 mm, the thicknesses of cooling lumens 86 , 87 , 88 and 89 (dimension B) are about 0.20 mm, and the wall thickness between antenna lumen 84 and cooling lumens 86 , 87 , 88 and 89 (dimension C), between cooling lumens 86 , 87 , 88 and 89 and catheter shaft 80 (dimension D), and between each of cooling lumens 86 , 87 , 88 and 89 (dimension E) are about 0.12 mm. Microwave antenna 16 (FIGS. 2A and 2B) is located in antenna lumen 84 . Cooling fluid, such as ionized water in one embodiment, is circulated through cooling lumens 86 , 87 , 88 and 89 in a manner generally known in the art. An example of a suitable cooling system is disclosed in the context of a urethral catheter in U.S. Pat. No. 5,300,099 entitled “Gamma Matched, Helical Dipole Microwave Antenna” and assigned to Urologix, Inc., which has been incorporated by reference herein. In one exemplary embodiment, cooling fluid is circulated into cooling lumens 86 and 87 and exits from cooling lumens 88 and 89 . In such an embodiment, cooling lumens 86 and 87 communicate with cooling lumens 88 and 89 near the distal end of catheter shaft 80 to provide a continuous fluid communication path in catheter shaft 80 . Alternatively, cooling lumens 86 , 87 , 88 and 89 may be configured with any other combination of fluid flow patterns, as is known in the art. In an exemplary embodiment, catheter shaft 80 includes a tip (shown in detail in FIGS. 7A and 7B) that enables percutaneous or laparoscopic insertion of catheter shaft 80 into internal tissue, as is generally known in the art. Catheter shaft 80 has a length of about 30 centimeters (cm) in an exemplary embodiment. Catheter shaft 80 preferably is sufficiently stiff to perforate soft tissue without buckling. Alternatively, catheter shaft 80 could be composed of a more flexible material if an appropriate introducer is provided to assist the insertion of catheter shaft 80 into tissue, or if a semi-rigid coaxial cable is used for the antenna or a stiffening element is employed to provide additional stiffness.
[0038] [0038]FIG. 6 is a diagram illustrating a heating pattern obtained during operation of a cooled microwave ablation device in a tissue phantom, utilizing catheter shaft 80 configured as shown in FIGS. 5A and 5B. The grid lines in FIG. 6 are spaced 1 cm apart. Upon energization of microwave antenna 16 with an input power of 45 Watts for an exposure time of 10 minutes, with coolant at 20° C. circulated through cooling lumens 86 , 87 , 88 and 89 (FIGS. 5A and 5B), a heating pattern was observed as shown in FIG. 6. Specifically, 30° C. isotherm 90 , 35° C. isotherm 92 ,40° C. isotherm 94 , 45° C. isotherm 96 and 50° C. isotherm 98 represent the temperature rise above baseline in the heating pattern achieved. During the operation shown in FIG. 6, there was no evidence of boiling water on the surface of catheter shaft 80 , indicating that the temperature of tissue adjacent to catheter shaft 80 was maintained below a boiling threshold and the resonant operation of microwave antenna 16 was not adversely affected by any change in the dielectric properties of the tissue surrounding catheter shaft 80 . This suggests that even greater depths of high temperature fields may be created by the application of higher power to microwave antenna 16 . The diagram of FIG. 6 shows that the cooled microwave ablation device is able to achieve temperatures above about 45° C. at a radial distance of about 1.2 cm from the outer surface of catheter shaft 60 , producing a total lesion diameter of about 2.7 cm (since catheter shaft 80 has a diameter of about 0.5 cm, although the drawing in FIG. 6 is not necessarily shown to scale). The cooled version of the microwave ablation device may achieve lesions having diameters exceeding about 4 cm in some embodiments.
[0039] [0039]FIG. 7A is a perspective view, and FIG. 7B is a side view, of tip 19 for use with the microwave ablation device of the present invention. Tip 19 includes a pointed piercing portion 100 and a mounting portion 102 . Tip 19 has a diameter (dimension F) that matches the outer diameter of the catheter shaft. Mounting portion 102 of tip 19 is configured to allow the cooling lumens of the catheter shaft to communicate with one another so that cooling fluid is able to circulate along the length of catheter shaft in the cooling lumens in both a feed path and a return path. In the exemplary embodiment illustrates in FIGS. 7A and 7B, piercing portion 100 of tip 19 is configured with sufficient stiffness, strength and sharpness to pierce into a targeted tissue region such as a kidney. The suitable materials for providing this capability are generally known in the art. In other embodiments, tip 19 may be blunt, with insertion achieved by other complementary surgical tools generally known and available to those skilled in the art. In either case, the microwave ablation device of the present invention is a “surgical” device in that it is directly inserted into targeted tissue without using a natural body lumen or cavity.
[0040] [0040]FIG. 8 is a section view of handle 11 for use with the microwave ablation device of the present invention. Handle 11 includes a catheter retaining portion 110 and a cooling fluid input/output portion 112 . A coaxial cable (not shown) is inserted into handle 11 at cable input aperture 114 , and is received into the catheter shaft inside catheter retaining portion 110 . Cooling fluid flows through a tube (not shown) which is received by cooling fluid input/output portion 112 of handle II, and enters the catheter shaft inside catheter retaining portion 110 . Handle 11 thus provides an effective manifold system for receiving the components of the interior portions of the catheter shaft. In an exemplary embodiment, handle 11 can be formed by injection molding, or may be a two-piece “clamshell” construction similar to the handle disclosed in U.S. application Ser. No. 09/733,109 filed Dec. 8, 2000 for “Thermal Therapy Catheter” by E. Rudie, S. Stockmoe, A. Hjelle, B. Ebner, J. Crabb, J. Flachman, S. Kluge, S. Ramadhyani and B. Neilson, which is hereby incorporated by reference.
[0041] The embodiment illustrated in FIG. 8 shows cooling fluid input/output portion 112 of handle 11 departing at an acute angle of about 45 degrees. Other embodiments of handle 11 may employ different acute angles or an obtuse angle of departure, to vary the forces experienced during operation of the microwave ablation device for maximum ease of use by a physician.
[0042] [0042]FIG. 9 is a graph illustrating exemplary thermal history data obtained experimentally from ex vivo operation of a non-cooled microwave probe similar to that shown in FIGS. 3A and 3B. The probe was operated for 30 minutes at a power level of 10-20 Watts such that the temperature at the tip of the probe remained constant. The temperatures at the probe tip and at radial distances 5 millimeters (mm), 10 mm and 15 mm from the tip were measured. The error bars on the graph represent the Standard Error of the Mean (SEM) of the measurements.
[0043] [0043]FIG. 10 is a graph illustrating exemplary thermal history data obtained experimentally from ex vivo operation of a cooled microwave probe similar to that shown in FIGS. 5A and 5B. The probe was operated for 10 minutes at a constant power level of 50 Watts with a coolant temperature of 37° C. (both power and cooling were discontinued after 10 minutes). The temperatures at the probe tip and at radial distances 5 millimeters (mm), 10 mm and 15 mm from the tip were measured. The error bars on the graph represent the Standard Error of the Mean (SEM) of the measurements.
[0044] A number of observations can be made about the measured thermal history data of FIGS. 9 and 10. The depth of high temperature heating achieved by the uncooled probe (as shown in FIG. 9) is less than the depth of high temperature heating achieved by the cooled probe (as shown in FIG. 10). This is primarily because of the reduction in power that is required to keep the temperature at the catheter shaft below about 95° C. to avoid tissue charring. Also, it should be realized that the peak temperature achieved by the uncooled probe during true in vivo operation will be somewhat lower than the peak temperature achieved by the uncooled probe during ex vivo operation (as shown in FIG. 10), due to the cooling effect of blood perfusion that occurs in vivo. However, despite the lower peak temperature, testing has shown that effective high temperature heating can be achieved at significant, controlled depth during the in vivo procedure, validating the efficacy of the present invention. An example of in vivo testing results is described below.
In Vivo Testing
[0045] Clinical trials were performed to evaluate the performance of the microwave ablation device of the present invention. Implantation of the device was made 26 mm into the lateral cortex of in vivo perfused porcine kidneys. A 3.5 mm non-cooled probe generally similar to that shown in FIGS. 3A and 3B was operated for eight samples, with power of 10-15 Watts maximum, adjusted to maintain the probe tip temperature below 95° C. The non-cooled probe was operated for 30 minutes. A 4.75 mm water cooled probe generally similar to that shown in FIGS. 5A and 5B was operated for five samples, with power of constant 50 Watts at 37° C. coolant temperature. The cooled probe was operated for 10 minutes. The kidneys were resected 3 hours after treatment and bisected for evaluation with gross measurements made 1.0 cm below the capsular surface.
[0046] Well-delineated lesions were produced with an inner zone of complete ablation and outer transition zone (see Table 1 below). Both probes were associated with minimal intraoperative hemorrhage (less than 20 cc) and maintained tissue integrity without parenchymal cracking. Neither probe showed renal artery nor vein thrombosis within the post-treatment perfusion period. While some tissue charring was identified with the non-cooled probe, it was not seen in the kidneys treated with the cooled probe. The cooled probe resulted in an enlarged ablation zone and reduced the treatment time needed without an apparent increase in procedural complications.
TABLE 1 Probe Type Treatment Time Total Diameter Inner Zone Diameter Non-cooled 30 minutes 1.8 ± 0.3 cm 1.2 + 0.2 cm Cooled 10 minutes 3.4 ± 0.5 cm 1.8 ± 0.3 cm
[0047] The present invention is a microwave ablation device for controllably creating thermal lesions to treat tissue. The impedance-matched antenna employed by the device reduces reflective losses and provides optimal performance in controlling the size and shape of the thermal field generated by the device to treat a targeted region of tissue. While either cooled or non-cooled embodiments of the microwave ablation device may be used with beneficial effect, the cooled embodiment provides the ability to create a larger lesion due to its ability to avoid defecation of tissue in the vicinity of the probe that prevents deep heating. The cooling is not used to preserve tissue adjacent to the probe or to avoid patient pain (which are the traditional uses of cooling), but instead serves to increase the size of the tissue region that is thermally damaged, including the tissue directly adjacent to the probe. The size of the catheter shaft and the cooling lumens can also be varied, yielding variations in lesion sizes and in other therapy parameters.
[0048] Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A tissue ablation device includes a catheter shaft having an antenna lumen, an impedance-matched microwave antenna carried in the antenna lumen of the catheter shaft, at least one cooling lumen in the catheter shaft around the antenna lumen for circulation of cooling fluid, and a microwave generator operatively coupled to the antenna for energizing the antenna to create a lesion in the targeted tissue around the catheter shaft having a controlled location and size. In an exemplary embodiment, a tip is attached to an end of the catheter shaft for penetrating the tissue targeted for treatment. The device is effective for laparascopic or percutaneous procedures to treat tissues such as the kidney. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 15/136,897 filed Apr. 23, 2016, Near-Touch Interaction to El Dokor, pending, which is a continuation of U.S. patent application Ser. No. 14/600,032 filed Jan. 19, 2015, titled “Near Touch Interaction with Structured Light” to El Dokor, now U.S. Pat. No. 9,323,395, which is a continuation of U.S. patent application Ser. No. 13/189,517 filed Jul. 24, 2011, titled “Near-Touch Interaction with a Stereo Camera Grid and Structured Tesellations” to El Dokor, now U.S. Pat. No. 8,970,589, which in turn claims the benefit of U.S. Provisional Patent Application Ser. No. 61/441,634 filed Feb. 10, 2011, titled “Near-Touch Interaction with a Stereo Camera Grid and Structured Tessellations” to El Dokor, the contents of each of these applications being incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] Multi-touch technology has become a standard modus of interaction with new touch screens. Such screens are becoming more pervasive, making their way into mobile technology and allowing for evolving forms of interaction. Such touch screen technology has enabled a shift in computing into a new brand of devices, including tablet computers, mobile devices and other touch screen supported systems. The problems with various single and multi-touch systems are many. Smudging is the most obvious one, in which the screen becomes unclear from regular usage. Hygiene is another issue in which the screen, especially if used by more than one person, may become unhygienic. Reliability and dependability of the screen are other considerations, along with the price associated with integrating a touch screen into a tablet device. Responsiveness that is associated with multi-touch gestures is another issue, since there exists a significant lag in the operation of the system itself.
[0003] A cheaper and more effective solution is to utilize optical sensors embedded in the bezel of the screen at various locations. Systems with sensors arrangements in the bezel are already available on tablets and other systems, and some are being made available in the near future. Optical-based interaction, if successful, is cheaper to install than a touch screen, and provides for a better and more reliable viewing quality. To enable such an optical based interface, depth has to be constructed in an area close to the screen's surface, i.e. a three dimensional representation of any objects positioned close to the screen's surface must be constructed so that movement relative to the screen may be determined. Once depth is calculated, replacing multi-touch gestural events with near-touch events that are emulating the same behavior becomes trivial.
[0004] There are no methods available today to reconstruct depth at such a close distance for real-time applications. Some work exists in the literature on spherical stereo, such as that presented in Li, Shigang. “Binocular Spherical Stereo” IEEE Transactions on Intelligent Transportation Systems (IEEE) 9, no. 4 (December 2008): 589-600. however such methods are computationally expensive and lack robustness for them to be applicable to a tablet computer. In accordance with embodiments of the present invention, a different stereo approach, presented in U.S. patent application Ser. No, 13/025,038, filed Feb. 10, 2011 by El Dokor et al., titled “Method and Apparatus for Segmentation of an Image”, the contents thereof being incorporated herein by reference, may be employed. A similar dewarping algorithm to that used by Li (noted above) may also be employed as a preprocessing step to the algorithm. A detailed description of this stereo algorithm has been presented in, for example, the above referenced '038 patent application. Building on the similar concepts of disparity computation with stereo, in accordance with the present invention, a novel approach is utilized for the implementation of near-torch systems.
[0005] There are other methods that are known to one of ordinary skill in the art for performing depth computation other than computational stereo. One such method utilizes an active light source with a structured pattern (these methods are sometimes referred to as active stereo). A pattern may be projected onto the field-of-view (FOV) from a light source close to the imager, and then the distance between the individual patterns is calculated. Some examples of this approach include Microsoft's Kinect™ Xbox™ peripheral, and PrimeSense's ASIC+Prime Sensor, as described in Meir Machline, Yoel Arieli Alexander Shpunt and Barak Freedman, “Depth Mapping Using Projected Patterns”, May 12, 2010, where various spots of light are utilized for the calculation of a depth map. In addition to the fact that the light source is usually in the infrared range, and requires a significant amount of energy, active stereo suffers from a number of practical and computational drawbacks. For instance, such methods are usually utilized to address depth computation at extremely large distances (relative to the screen, in the context of a few inches), forcing the light source to be very power-consuming and bulky. The data from the depth images have to be evaluated over a number of frames, making the data sluggish and introducing a significant amount of motion blur and computational artifacts that become apparent in performance. Such methods are inappropriate for near-touch interaction.
[0006] Therefore, it would be desirable to present a near touch system that overcomes the drawbacks of the prior art.
SUMMARY OF THE INVENTION
[0007] In accordance with various embodiments of the present invention, a method for determining near touch interaction that is significantly more reliable and easy to embed than presently available methods, utilizing depth compute algorithms, is presented. Additionally, the introduction of a light source to smooth disparity computations and the overall generated depth map in targeted regions for further refinement is also presented in accordance with various embodiments of the present invention, and helps to improve the quality and consistency of the depth map.
[0008] Near Touch System
[0009] In accordance with embodiments of the present invention a medium of interaction that is to be enabled must first be defined. A near-touch interface may be used to define any interface that can be operated at a distance of roughly 4-14 inches away from a screen. As noted above, there are many technologies that are available today to enable a near-touch system commercially. Some may utilize infrared sensors; others may utilize ultrasound ones. A third category may utilize time-of-flight cameras.
[0010] The inventive approach utilizes depth computation, referred to in the above referenced '038 patent application, to produce a depth map. Cameras are preferably utilized with wide-angle lenses, and a dewarping step may be used on the images to remove various warping artifacts and effects that are associated with a wide-angle lens. Dewarping on the data may first be attempted such that two images are input to the system that are mostly free of any lens distortions.
[0011] The inventive approach presented in accordance with various embodiments of the present invention may also utilize the screen as a light source, to also minimize the entropy that is associated with a depth estimate, removing the need for further iterating and segmenting larger regions and reducing computational complexity, as described in the above referenced patent application. Additionally, for high-speed LED screens, patterns can be flashed onto the user's hand (or other object being used for near touch) to help improve depth calculations. This is similar to what has been suggested in active stereo methods, where an external IR light source is utilized. Instead, in accordance with the present invention, the screen itself may be utilized as a directed light source, and only targeting specific regions that may require additional information and help in forming an accurate depth map.
[0012] Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification and drawings.
[0013] The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts that are adapted to affect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a more complete understanding of the invention, reference is made to the following description and accompanying drawings, in which:
[0015] FIG. 1 is a flowchart diagram depicting an overall process flow in accordance with a preferred embodiment of the present invention;
[0016] FIG. 2 (including FIGS. 2( a )-( d ) ) is an example of measurements in accordance with a preferred embodiment of the present invention; and
[0017] FIG. 3 is a perspective view of a tablet computing device employing sensors in accordance with a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] One or more embodiments of the invention will now be described, making reference to the following drawings in which like reference numbers indicate like structure between the drawings.
[0019] An overview of a preferred approach in accordance with an embodiment of the present invention is shown in FIG. 1 . As is shown in FIG. 1 , at step 110 one or more images are acquired, and then at step 120 , these images may be dewarped if desired or determined necessary or advantageous. A disparity is computed at step 130 , and at step 140 target regions may be identified and ilium hated with screen tessellations. Finally, at step 150 , disparity is refined.
[0020] In accordance with one or more embodiments of the present invention, wide angle lenses are preferably utilized. Such wide angle lenses allow for a wide field of view to be acquired, allow for the viewing of objects close to the cameras, and thus the display, and also produce a shallow depth of field, thus blurring a background or other objects potentially in the field of view other than the object to be tracked. One or more lenses on the cameras may further be provided to play a role of one or more multiple bandpass filters to allow and block passage of different frequencies of the light spectrum, as may be determined to be desirable.
[0021] The inventive approach allows for a computationally less expensive algorithm and enables a fast iteration with which the initial depth estimate may be further smoothed. In accordance with the invention, an ideal segment, s, exists in three-dimensional space. The estimated segment, {tilde over (s)}(x,y,{tilde over (d)}) of the ideal segment exists only in one disparity value. Hence, the initial computed disparity represents the orthogonal projection of the segment, s, onto disparity plane, {tilde over (d)}. This is a many-to-one mapping. So, one can define the relationship as:
[0000] s ( x,y,d )={tilde over ( s )}( x,y, {tilde over ( d )})+␣( x,y ) Equation 1
[0000] where Ψ represents the difference, in disparity between the original segment and its orthogonal projection. Thus, Ψ is an ordered sequence that has the same dimensions as the given segment, and can be approximated by a mixture of Gaussians. Approximating Ψ then becomes the real challenge solved in accordance with embodiments of the present invention, to save computation and prevent the need for a further iterative step in the process of formation of the depth map.
[0022] Estimating the Disparity Difference Ψ
[0023] An efficient means for estimating Ψ is to compute the disparity associated with an active pattern that is produced from the screen or monitor. That pattern is used to produce a coarse grid of depth values. Some points on this grid do coincide with the overall depth estimate, and some don't.
[0024] Define the actual set of all disparities that are associated with a given ideal segment, s, as:
[0025] D={D 1 , . . . , D n }, such that the estimated disparity, {tilde over (d)}, is assigned only one value from the set, meaning
[0000] {tilde over (d)}□{D 1 , . . . , D n } Equation 2
[0000] Estimating Ψ(x,y) for the individual pixels,
[0000] Ψ( x,y )≈ GMM ( S 1 ,S 2 ,S 3 )+α Equation 3
[0000] where S 1 , S 2 , and S 3 , are the three nearest values from the structured light respectively and α is the associated smoothing factor (as described in Meir Machline, Yoel Arieli Alexander Shpunt and Barak Freedman, “Depth Mapping Using Projected Patterns”, May 12, 2010, and GMM represents a mixture of Gaussians. More neighboring values can be included in the estimation. The total number of Gaussian mixtures doesn't necessarily have to be limited to three.
[0026] An object that has been estimated at a given disparity is preferably further refined with a coarse disparity estimate within the vicinity of the estimated disparity value, based on the approximation of Ψ(x,y) that can be obtained from utilizing a structured light source. In a preferred embodiment of the present invention, this structured light source is preferably utilized over only a portion of the object, and in particular, used to aid in refining the depth map for a portion of the object in which such a depth map is difficult to determine, or otherwise is indicative of benefitting from such additional refinement. The light source may further be employed in one or more frames, these frames not necessarily being consecutive. The projections may further be selected in a manner to be shielded from the field of view of a user, or otherwise blocked from view. Such structured light may be further provided as patterns changed at very high speeds, and targeting only portions of the field of view where it is determined such structured light may be helpful in further refining depth estimations. Further, the structured light is preferably adaptive to various environmental conditions, thus becoming brighter when, for example, ambient light is brighter, and becoming less bright when ambient light is less bright. Such patterns may vary in one or more of size, location, orientation or frequency depending on size and depth of the targeted region. These structured light patterns may be further interleaved with actual displayed data so that the structured light may be displayed without being perceived by the user.
[0027] The resulting modified segment s′(x,y,d′) represents a smoothed version of the original computed estimate, {tilde over (s)}. This smoothed version allows for access to a detailed depth map represented in the data, smoothed over a range of disparities. If a segments completely parallel to the field-of-view, s and {tilde over (s)} are nearly identical. If the segment is slanted, away or towards the cameras in the field-of-view, s and {tilde over (s)} begin to differ quite significantly. The implications and consequences of this idea will be further considered below.
[0028] An easy way to visualize this approach, and to justify the utilization of a lower-resolution coarse depth estimate, to help smooth and improve upon the depth estimate, is to view the projection of each of the two cases (slanted towards and away from the screen) onto the scene, and to evaluate the entropy that is associated with such cases.
[0029] FIG. 2 highlights the two cases. In FIG. 2( a ) , an object is slanted, hence having pixels at a range of disparities. In FIG. 2( b ) , an object is mostly upright relative to the FOV, hence having most of the pixels at one or two disparity values. Looking at the projections of both objects onto the disparity plane, the uncertainty or entropy shown in FIG. 2( c ) is significantly higher than that of FIG. 2( d ) . Thus, FIG. 2( a ) represents an object that is slanted and its associated projection in FIG. 2( c ) . The error between actual and computed disparity can be quite high. In FIG. 2( b ) , the object s mostly normal to the field of view and so the error between it and its projection FIG. 2( d ) is significantly lower. In accordance with various embodiments of the invention, this uncertainty in the depth map can be represented and exploited. It can also be mitigated through the utilization of a structured light source projected onto portions of the field-of-view, once such an initial depth map estimate is evaluated.
[0030] Disparity Smoothing with Structured Light Tessellations
[0031] The generated disparity map represents a surface-based approach to disparity computation. As mentioned in the above referenced '038 patent application, further refinement of the segments can be accomplished by breaking up larger segments both horizontally and vertically. To avoid having to perform this extra computation on a mobile or other system, one approach may be to utilize the screen for displaying a pattern onto the user's hand, and once a hand has been isolated in the FOV, then compute disparity of the pattern.
[0032] The smooth disparity estimate represents an integration of the disparity values over a number of rows. From the above referenced '038 patent application, the goal is to have s and {tilde over (s)} overlap nearly entirely at one of the candidate disparity values. The appropriate disparity is estimated as one that maximizes the ratio of the subsequence, relative to its sequence. However, there is a simplifying assumption that may be made in the estimation of disparity, since clustering groups of pixels together fits such pixels planarly, depriving them of any continuous and gradual change. The disparity value that is associated with large objects represents an approximation of the value that is associated with every pixel in such objects. A better approximation of the true value still requires a further step, as mentioned earlier.
[0033] Once regions have been extracted from the coarse disparity map, such regions may be depth-computed by projecting a series of coarse tessellations and imposing a smoothing value, to be associated with the actual data. Every tessellation has a series of computed disparity values that are based on a combination of the original disparity estimate as well as the coarse structured light values, presented in Equation 3 above.
[0034] it is worth noting that:
[0000] Pr(d|S)□Pr(d|{tilde over (d)} o ), □(x′,y′)□D Equation 4
[0000] such that D represents a subset of values of the image, representing the structured set. So, although fewer in number, absent of an iterative step, the structured light depth approximations represent an upper limit on the probability of the computed disparity for the pixels with such values, referenced earlier, provided the computed depth is accurate. However the computed disparities based on the tessellations are too few in number and too coarse, in addition to the number of drawbacks presented earlier in the document. The solution that is being presented here in accordance with an embodiment of the invention preferably including combining both approaches actually leads to an enhanced probability limit. One can observe:
[0000] Pr(d|d′,S)□Pr(d|{tilde over (d)} o ), □(x,y) Equation 5
[0035] Minimizing Entropy
[0036] Hypothetically, for an object that is completely normal to the FOV, the entropy associated with its disparity computation is minimal, since the calculated disparity is based on a computational stereo algorithm that utilizes parallel surfaces to fit segments to their respective disparities. For an object that is slightly tilted in the field of view the entropy that is associated with computing its disparity is greater, since the object's disparity values are distributed, as was presented in the preceding section, and illustrated in its associated figures.
[0037] Another way to view this approach is from an entropy-minimization standpoint. For a given segment s, with an estimated segment, {tilde over (s)}, and associated estimated disparity {tilde over (d)}, the more depth values that are associated with the segment, the higher the entropy value that is associated with the segment's estimated disparity {tilde over (d)} and vice versa. So, if a segment is perfectly orthogonal to the field-of-view, then the entropy is very close to zero, since the depth estimate is very accurate. However, for slanted segments, the entropy increases significantly.
[0038] Since the secondary step that has been described above is performed on the data, depth smoothing is accomplished through an estimate of Ψ. The different data values, Ψ(x,y), of the tessellations, represent points of higher certainty in the disparity estimates. The overall depth map is then recomputed based on the approximated To minimize the entropy of the estimated value, the data, d′, are smoothed or “influenced” by Ψ and redistributed.
[0039] Define the conditional entropy, Q(d|{tilde over (d)}), associated with a depth estimate, d′, as:
[0000]
Q
(
d
|
d
~
)
=
•
•
i
Pr
(
d
|
d
~
)
×
log
Pr
(
d
|
d
~
)
Equation
6
[0000] Since the conditional probability, Pr(d|{tilde over (d)}), is defined as the probability of getting a disparity d, when the computed (in this case, observed) disparity is {tilde over (d)}, then, one can discern the relationship:
[0000] Pr(d|{tilde over (d)},S)□Pr(d|{tilde over (d)}) Equation 7
[0000] where S represents the presence of a structure that is associated with the data or a portion of the data, based on the active light source. It is possible to infer the joint conditional entropy, in relation to the conditional entropy associated with the computed depth map:
[0000] Q(d|{tilde over (d)},S)□Q(d|{tilde over (d)}) Equation 8
[0040] Entropy minimization becomes very useful in near-touch applications, and highlights how the presence of a directed active stereo tessellation can effectively smooth out the computed and identified depth surfaces, building a more reliable depth map. Having a greater certainty in the data due to the integration of an active light source is a computationally efficient means of identifying “touch points”, regions in the FOV that are close enough to activate the system and replace multi-touch. Instead of the standard light source approach, a defined region with a projected light source becomes a more efficient approach to depth estimation in near-touch applications.
[0041] Operating Under Various Lighting Conditions
[0042] Heterogeneous Sensors to address all Lighting Conditions. Scene analysis may be classified through three sets of lighting scenarios, without loss of generality:
Indoor lighting: normal lighting conditions in which there is abundant ambient lighting. In such a case, the system may be normally configured to handle very good lighting conditions, and after dewarping, the stereo algorithm should perform very well, with refinement in the form of the structured light tessellations, enabling a smooth depth map. Outdoor lighting: in such a case, the reader is referred to the above referenced '038 patent application, in which all the different lighting conditions can be accounted for through a very aggressive segmentation/tracking algorithm. Night-time/NIR conditions: the screen itself may be employed as an active light source. The value associated with the tessellations is increased, while the screen illuminates the FOV and still enables near-touch applications. In an alternative embodiment of the invention, one or more pairs of stereo cameras employed in accordance with various embodiments of the present invention may comprise cameras that cover both a visible and infrared portion of the electromagnetic spectrum. Alternatively multiple cameras may be employed, together covering such a portion of the spectrum. In this manner, in dim light, infrared information may be relied upon, in part or whole, to aid in determining or refining disparity. If ambient light is determined to be sufficient for visible spectrum viewing, the infrared portion of the data may be disregarded.
[0046] To accommodate for the different scenarios, a very good option is to preferably utilize a grid of sensors, as depicted in FIG. 3 . As is shown in FIG. 3 , a tablet computer or other mobile device 310 is shown with a screen 320 and a sensor grid 330 embedded therein. In such a case, the sensor grid may be sensitive to a broad range of lighting conditions, and the system may seamlessly switch between any different sensors depending on environmental conditions.
[0047] Advantages of this Approach
[0048] This approach, as set forth in the various embodiments of the present invention, has many advantages. The disparity computation step provides a very detailed depth map in the x-y dimension with significant resolution in the z-dimension. The addition of a structured light source emanating from the tablet's screen itself further refines aspects of this depth map, to better address ambiguous data and provide for further accuracy, and a reduction in the uncertainty that is associated with the data. Typical structured light approaches have proven to be cumbersome, requiring a strong light source, and generating a coarse depth map. Furthermore, there has never been an attempt to utilize a targeted structured light, activating only in specific regions of the field of view, especially ones that are masked away from the user's view, and in which the user's hand is at close proximity to the screen. This approach reduces computational complexity, and improves responsiveness and accuracy of the overall system. Many other advantages may be realized in accordance with various embodiments of the invention.
[0049] A new approach for embedded disparity computation for near-touch systems is presented. This approach is efficient and fast, utilizing a combination of a novel stereo algorithm as well as targeted light strictures projected on parts of the scene by the screen itself, at distances close to near-touch, in the form of tessellations. The computed tessellations are then utilized to smooth the depth map, and minimize the uncertainty that is associated with the data. The system is very efficient and utilizes a previously developed depth map. The realization of the system is accomplished with a grid of smart sensors that are used, in conjunction with the screen, to address various lighting conditions. Other benefits may be apparent in accordance with application of the present invention. Indeed, while a near-touch system is described, embodiments of the invention may be applied to any gesture-relevant situation (applications) or even a three-dimensional scene reconstruction near the surface of a tablet device.
[0050] In accordance with various embodiments of the invention, a number of benefits may be provided, including the following: A new algorithm utilizing both a passive stereo algorithm that is based on our previous work and a structured, targeted tessellation projected on the field-of-view from the screen. An advanced sensor grid to address various lighting conditions that are associated with the system. Identification of “touch points” based on the produced smooth disparity map. Utilization of the disparity map with a multi-touch API or a 3D API.
[0051] In accordance with one or more embodiments of the present invention, it is further contemplated that various hardware configurations, including sufficient processing, storage and transmission systems are provided to support the various processors and steps described above. It is further contemplated that such storage and processing elements may be provided locally within a device, or remotely on a cloud or other remote computing or storage environment. In such a situation, communication systems operating over one or more available communication systems may be employed, and also providing for an integrated device capable of combining information from one or more locally and remotely processed, stored or otherwise manipulated information or programming.
[0052] Various embodiments of the invention further contemplate a computer program stored on a non-volatile computer medium within the device, or at a remote location. The computer program causing a computer or other processor in the device or remote location to implement an APT to aid in performing one or more of the following steps.
[0053] Generating or refining a coarse depth map
[0054] Providing any above-noted control over fine-tuning the light tessellations
[0055] Determining one or more critical data points for acquisition
[0056] Providing control over various screen functionality
[0057] Providing integration and replacement of touch-based or multitouch controls
[0058] Allowing for integration with one or more artificial intelligence (AI)
[0059] algorithms for recognition and scene analysis
[0060] Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification and drawings.
[0061] The invention accordingly comprises the several steps and the relation of one or more of such steps with respect to each of the others, and the apparatus embodying features of construction, combinations of elements and arrangement of parts that are adapted to affect such steps, all as exemplified in the following detailed disclosure, and the scope of the invention will be indicated in the claims. | A near-touch interface is provided that utilizes stereo cameras and a series of targeted structured light tessellations, emanating from the screen as a light source and incident on objects in the field-of-view. After radial distortion from a series of wide-angle lenses is mitigated, a surface-based spatio-temporal stereo algorithm is utilized to estimate initial depth values. Once these values are calculated, a subsequent refinement step may be applied in which light source tessellations are used to flash a structure onto targeted components of the scene, where initial near-interaction disparity values have been calculated. The combination of a spherical stereo algorithm, and smoothing with structured light source tessellations, provides for a very reliable and fast near-field depth engine, and resolves issues that are associated with depth estimates for embedded solutions of this approach. | 6 |
FIELD OF THE INVENTION
A diffuse reflectance method and apparatus are used to determine thickness of an infrared translucent layer on a metal substrate.
BACKGROUND OF THE INVENTION
In a past, collimated beams, coming from an interferometer, were used to produce an interferogram of a relatively thick silicon layer that had been epitaxially coated onto a silicon wafer. A single angle of incidence was made with the silicon layer, by collimated interferometer beams. Reflections of the collimated beams were produced. Again, collimated interferometer beams were used in the past to form an interferogram. The interferogram was used to determine the thickness of the relatively thick silicon layer.
The present diffuse reflectance method and apparatus provide for an accurate measurement of thickness of a relatively thin infrared translucent layer on a metal substrate. An example of such a relatively thin translucent layer on a metal substrate is a thin beryllium oxide region that is formed into a beryllium metal part.
The present method uses diffuse reflectance to measure thickness of the relatively thin beryllium oxide region. Parallel infrared interferometer beams are emitted from an interferometer. A concave mirror is used to converge the parallel beams into converging infrared interferometer beams. Converging interferometer beams are sent onto both the beryllium oxide region and underlying beryllium substrate. Diverging infrared interferometer rays are diffusely reflected from the beryllium oxide region and beryllium substrate, after reflection of the converging infrared interferometer beams from the beryllium oxide region and from the beryllium substrate.
The diverging interferometer rays are collimated and analyzed by means of Fourier transform infrared spectroscopy.
A concave mirror is used in the present apparatus to collimate, that is make parallel, the diverging interferometer beams.
Different angles of incidence are made between the converging interferometer beams and a line perpendicular to the surface of the beryllium oxide region.
A movable mirror of the inteferometer is scanned and the overall intensity of interfereing diffusely reflected rays, coming from the beryllium oxide region and beryllium substrate, is detected. An inteferogram is produced by recording the intensity versus the increment amount of scan distance. Sidebursts occur in the interferogram due to reflections above and below the oxide region. An amount of displacement of a first sideburst, in the interferogram, from a centerburst, in the interferogram, is measured. The amount of displacement is indicative of the thickness of the beryllium oxide region.
The present diffuse reflection method and apparatus were used to measure the thickness of a beryllium oxide region that had been formed in a beryllium substrate. Beryllium oxide thicknesses ranging from 0.67 microns to 4 microns were measured.
A beryllium oxide region is formed in a beryllium substrate by oxiding the beryllium substrate. The beryllium oxide region could be a beryllium oxide region that was formed by oxidizing a beryllium part.
It is noted that when a beryllium substrate is oxidized, there is a less uniform interface region than the interface region that occurs when a silicon layer is epitaxially placed on a silicon wafer.
A prior art software program, that had been used in the prior art measurement of a thickness of a relatively thick epitaxial silicon layer coated onto a silicon wafer, was modified. The software was used to measure thicknesses of the silicon layers that had thicknesses that ranged from 25 microns to 150 microns. The prior art software program operated by subtracting an interferogram of the epitaxial layer under examination from an interferogram of a reference epitaxial layer of known thickness. The resultant subtracted interferogram was searched by the software until a first major sideburst was found. At this point, the program calculates the thickness of the silicon epitaxial layer, using the distance of the sideburst from a centerburst of the subtracted interferometer, and the refractive index of the silicon epitaxial material.
Again, the prior art software program operated by subtracting an interferogram of the silicon layer under examination from an interferogram of a reference silicon layer of known thickness. The resultant subtracted interferogram was searched by the software until a first major sideburst was found. At this point, the program calculates the thickness of the silicon layer, using the distance of the sideburst from a centerburst of the subtracted interferometer, and the refractive index of the epitaxial silicon.
The prior art software program was modified in order to be used with the new method and apparatus. The modified software program can be used to measure the thickness of a relatively thin beryllium oxide region in a beryllium substrate. Such an oxide region might have a thickness from between 0.67 microns to 4 microns. A refractive index value of 1.8 was selected for a beryllium oxide region, in the modified software program. This value is used with the modified software program.
As part of its broad scope, a producibility program supported applications of new advancements from a wide range of technical disciplines to improvements of manufacturing and testing techniques for instruments. In this regard, steps were taken to prove that a nondestructive thickness measurement of beryllium oxide regions, in anodized beryllium components, was possible using diffuse reflectance Fourier transform infrared spectroscopy. Further steps were taken to demonstrate that the method could be readied for production use. By first demonstrating the interferometric principle with spectral patterns obtained from anodization regions of varying thicknesses, the modified prior art software program was incorporated into the disclosed method.
The modified software program enabled automated, nondestructive beryllium oxide region measurement by operators on a production line. The software program operated to the satisfaction of production and design engineers.
The disclosed diffuse reflection Fourier transform infrared spectroscopic method and apparatus, for measuring thicknesses of beryllium oxide regions, developed under the producibility program, can provide useful processing information about anodization region thickness and region uniformity, and to determine changes in the region's chemical composition. An implementation plan was developed by production engineers to determine how the disclosed method and apparatus, and the information that it generates, could be used.
When a group of beryllium components are manufactured, several production samples are routinely destroyed by an acid-etch technique wherein one obtains the thickness of the anodization, that is oxide, region, by etching away a small area of the oxide region and measuring the resultant hole with a form tally instrument. Aside from the destruction of useful hardware, there is some question regarding the accuracy of the acid-etch techniques. This issue warranted the use of an alternate thickness measurement method.
The disclosed diffuse reflectance method and apparatus will preserve hardware and improve the accuracy and efficiency for determining oxide region thicknesses.
SUMMARY OF THE INVENTION
A method for producing an interferogram of an infrared translucent layer that is on a reflective substrate, comprising generating parallel infrared interferometer beams by means of an infrared interferometer, converging the parallel infrared interferometer beams into converging infrared interferometer beams, sending the converging infrared interferometer beams onto the infrared translucent layer to produce diffusely reflected infrared interferometer rays from above and below the infrared translucent layer, and making the diffusely reflected infrared interferometer rays into parallel reflected infrared interferometer rays.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a gas bearing gyro rotor assembly.
FIG. 2 is optical ray diagram of an interferometer, with a moving mirror of the interferometer having a first position to provide destructively interfering beams.
FIG. 3 is optical ray diagram of an interferometer, with a moving mirror of the interferometer having a second position to provide constructively interfering beams.
FIG. 4 is optical ray diagram of an interferometer, with a moving mirror of the interferometer having a third position to provide destructively interfering beams.
FIG. 5 is an optical ray diagram of a diffuse reflectance Fourier transform infrared spectrometer that is being used to determine the thickness of a beryllium oxide region in a beryllium plate.
FIG. 6 is an optical ray diagram of converging interferometer beams that are impinging onto an anodized beryllium metal substrate.
FIG. 7 is an interferogram 50 of a beryllium oxide region whose thickness is to be determined, a reference interferogram 54 and a subtracted interferogram 58 . Interferogram 50 is examined to identify its centerburst and first sideburst by means of reference interferogram 54 . Subtracted interferogram 58 is made by subtracting the value of reference interferogram 54 from the value of interferogram 50 .
FIG. 8 is a gage that can be used to determine oxide thickness directly from an interferogram of the oxide.
FIG. 9A is an interferogram made by measuring intensity of a diffusively reflected interferometer beam coming from a 25 microinch thick beryllium oxide region, as a moving mirror of an interferometer, that produces the interferometer beam, is scanned from a position shown in FIG. 2 to a position shown in FIG. 4 . The interferogram of FIG. 9 is as interferogram 50 of FIG. 7 .
FIG. 9B is an interferogram made by measuring intensity of a diffusively reflected interferometer beam coming from a 50 microinch thick beryllium oxide region, as a moving mirror of an interferometer, that produces the interferometer beam, is scanned from a position shown in FIG. 2 to a position shown in FIG. 4 .
FIG. 9C is an interferogram made by measuring intensity of a diffusively reflected interferometer beam coming from a 75 microinch thick beryllium oxide region, as a moving mirror of an interferometer, that produces the interferometer beam, is scanned from a position shown in FIG. 2 to a position shown in FIG. 4 .
FIG. 9D is an interferogram made by measuring intensity of a diffusively reflected interferometer beam coming from a 100 microinch thick beryllium oxide region, as a moving mirror of an interferometer, that produces the interferometer beam, is scanned from a position shown in FIG. 2 to a position shown in FIG. 4 .
FIG. 9E is an interferogram made by measuring intensity of a diffusively reflected interferometer beam coming from a 400 microinch thick beryllium oxide region, as a moving mirror of an interferometer, that produces the interferometer beam, is scanned from a position shown in FIG. 2 to a position shown in FIG. 4 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
An anodized gas bearing gyro rotor assembly 10 is shown in FIG. 1 . The assembly 10 has two beryllium thrust plates 12 and 14 , a beryllium shaft 16 , and a rotor 18 , as shown in FIG. 1 . The plates, shaft and rotor have tight dimensional requirements, the dimensional requirements being on the order of several microinches. A microinch is symbolized by the letter u. Grooves 19 formed in the shaft 16 and grooves 19 A formed in plates 12 and 14 , allow a gas to pass between the shaft 16 and the rotor 18 and to thereby support rotor 18 away from shaft 16 .The beryllium plates 12 and 14 , and the beryllium shaft 16 are composed chiefly of beryllium metal.
The beryllium plates 12 and 14 and beryllium shaft 16 undergo a surface oxidation conversion reaction to yield topical beryllium oxide regions in the beryllium metal. A topical beryllium oxide region 20 is formed in plate 12 . Beryllium oxide region 20 is over beryllium metal 12 A of plate 12 , as shown in FIG. 6 . The thickness of the beryllium oxide region is unknown when formed. However to explain the present method, an interferogram 50 of FIG. 7 for a 25 microinch thick beryllium oxide region 20 is used. The beryllium oxide region 20 is an infrared translucent layer. The beryllium metal 12 A is a reflective substrate. A beryllium oxide region(not shown) is formed in beryllium plate 14 . A beryllium oxide region 21 is formed in beryllium shaft 16 .
The beryllium oxide regions are thin enough to allow infrared light to pass there through. Infrared light is reflected by the beryllium metal that is beneath the beryllium oxide regions.
The beryllium oxide regions are fabricated with the intent that the depth of each of the beryllium oxide regions be approximately 65 microinches (u″).
Nondestructive type testing, by the present method and apparatus, of the thicknesses of the beryllium oxide regions of the gas gyro assembly 10 , is desirable. For, the gas gyro assembly 10 is one of the most critical and costly components of a pendulous integrating gyro accelerometer.
Nondestructive measurements of the thicknesses of the beryllium oxide regions are performed by the present diffuse reflectance Fourier transform infrared spectroscopy (DRFTIS) method and apparatus. The principle behind such nondestructive measuements is based on the wave nature of light. DRFTIS makes use of the surface reflectance properties of the underlying beryllium, the reflectance properties of the beryllium oxide region, and the refractive index value of a beryllium oxide region.
In FIGS. 2, 3 and 4 a generic layout of optics for a Michelson infrared interferometer 25 , plus a concave converging mirror 40 , are shown. An infrared light source 26 sends a beam 28 of infrared light toward a beam splitter 30 . The beam splitter 30 splits beam 28 into infrared interferomter beams 32 A and 32 B. The infrared interferometer beam 32 A is reflected by fixed mirror 37 and passes through beam splitter 30 toward concave mirror 40 . The infrared interferometer beam 32 B is reflected by movable mirror 38 and is reflected by beam splitter 30 toward concave mirror 40 . Infrared interferometer beams 32 A and 32 B are parallel before reaching mirror 40 .
The paths of the parallel infrared interferometer beams 32 A and 32 B are toward concave mirror 40 . The concave mirror 40 reflects infrared interferometer beam 32 A, to produce infrared interferometer beam 44 A. The concave mirror 40 reflects infrared interferomter beam 32 B, to produce infrared interferometer beam 44 B. The concave mirror 40 causes infrared interferometer beams 44 A and 44 B to converge toward each other.
Interferometer 25 has a fixed, that is stationary, mirror 37 . Interferometer 25 has a movable mirror 38 . The mirror 38 is continuously moved, that is scanned, as shown by FIGS. 2, 3 and 4 , to produce an interferogram of a beryllium oxide region, as further described below.
FIGS. 2, 3 and 4 respectively show infrared interferometer configurations for destructive interference, for constructive interference and for destructive interference. The movable mirror 38 is scanned from the configuration of FIG. 2 to the configuration of FIG. 4 to produce an interferogram.
A diffuse reflectance Fourier transform infrared spectroscopic apparatus 39 is shown in FIG. 5 . The apparatus 39 includes a beryllium thrust plate 12 that has a beryllium oxide region 20 . The apparatus 39 could alternately be made to include an alternate component, such as beryllium shaft 16 that has a beryllium oxide region 21 , in place of beryllium thrust plate 12 .
In FIG. 5, parallel infrared interferometer beams 32 A and 32 B, that are emitted by th interferometer 25 , are directed by flat mirror 41 and flat mirror 42 toward concave mirror 40 . Concave mirror 40 reflects the parallel infrared beams 32 A and 32 B, coming from the interferometer 25 , and produces converging infrared interferometer beams 44 A and 44 B. Infrared interferomter beams 32 A and 32 B converge toward each other due to reflection of the beams 32 A and 32 B by concave mirror 40 .
The converging infrared interferometer beams 44 A and 44 B, coming from the concave mirror 40 , are sent onto thrust plate 12 . The thrust plate 12 reflects infrared interferometer beam 44 A to produce diffuse reflected infrared interferomter rays 45 A and 46 A. The thrust plate 12 reflects infrared interferometer beam 44 B to produce diffuse reflected infrared interferometer rays 45 B and 46 B.
A concave collecting mirror 43 collects and collimates, that is makes parallel, the diffuse reflected infrared rays 45 A, 46 A, 45 B and 46 B. Diffuse reflected infrared rays 45 A, 46 A, 45 B and 46 B are collected and collimated, as shown in FIG. 5 . Again, a concave collecting mirror 43 collects and makes parallel the diffuse reflected infrared rays 45 A, 46 A, 45 B and 46 B.
The parallel infrared rays 45 A, 46 A, 45 B and 46 B are reflected by flat mirror 47 . The parallel rays 45 A, 46 A, 45 B and 46 B are then reflected by flat mirror 48 into a detector 49 .
A varying signal is generated by detector 49 , as movable mirror 38 of interferometer 25 of FIG. 5 is scanned from the position shown in FIG. 2 to the position shown in FIG. 4 . The strength of the signal from detector 49 is dependent on the amount of energy in the detected interfering infrared rays 45 A, 46 A, 45 B and 46 B, as movable mirror 38 is scanned. That is, the strength of the signal is proportional to the overall strength of the reflected interfering infrared rays 45 A, 46 A, 45 B and 46 B.
The signal is sent from detector 49 to a recorder 49 A and recorder produced a trace proportional in height to the strength of the signal. A controller 49 B coordinates the scanning of mirror 38 with the position of a trace in recorder 49 a . The trace is interferogram 50 , as shown in FIG. 7 .
As shown in FIG. 6, the converging beam 44 A produces rays 45 A and 46 A. Converging beam 44 B produces rays 45 B and 46 B. Rays 45 A and 45 B are produced, respectively, as a result of beams 44 A and 44 B being reflected from the top of beryllium oxide region 20 . Rays 46 A and 46 B are produced, respectively, as a result of beams 44 A and 44 B being reflected one or more times from beryllium metal 12 A that is under the oxide region 20 .
Rays 45 A and 46 A are parts of beam 44 A. Rays 45 B and 46 B are parts of beam 44 B. The collected rays 45 A, 46 A, 45 B and 46 B are together detected by detector 49 .
The collected rays 45 A, 45 B, 46 A and 46 B are all collected by detector 49 . An interferogram 50 , shown in FIG. 7, is produced due to their interference at the oxide region 20 and underlying beryllium 12 A, as mirror 38 of interferometer 25 is scanned inward toward the beamsplitter of interferometer 25 . The movable mirror 38 of the interferometer 25 is scanned to produce a set of intensities in detector 49 . This set of intensities is interferogram 50 .
The intensity produced by the interference of rays 45 A, 45 B, 46 A and 46 B is essentially zero when the moving mirror 38 is at the three halves point, in distance, to the beamsplitter 30 , with respect to the distance of beamsplitter 30 to mirror 37 . This arrangement is shown in FIG. 2 . At the three halves mark, the IR rays 45 A and 46 A are a half cycle out of phase with respect to IR rays 45 B and 46 B, thereby leading to total destructive interference (minimum energy throughput). This interference produces the left end of interferogram 50 of FIG. 7 .
The rays 45 A, 46 A, 45 B and 46 B interfere to produce a maximum intensity in detector 49 , known as a centerburst 53 , when the mirrors 37 and 38 of interferometer 25 are equidistant from the beamsplitter 39 , as shown in FIG. 3 . This interference produces the center burst 53 of interferogram 50 of FIG. 7 .
The intensity produced by the interference of rays 45 A, 45 B, 46 A and 46 B diminishes to zero as the moving mirror 38 approaches the halfway point, in distance, to the beamsplitter 39 , with respect to the distance of beamsplitter 39 to mirror 37 as shown in FIG. 4 . At the halfway mark between the moving mirror 38 and the beamsplitter 39 , the IR rays 45 A and 46 A are again a half cycle out of synchronization with rays 45 B and 46 B, thereby leading to total destructive interference (minimum energy throughput). This interference produces the right end of the interferogram 50 of FIG. 7 .
Diffuse reflectance Fourier transform infrared spectrometry is generally discussed. However there is no teaching or suggestion of transmission of diffuse infrared beams through a translucent oxide region, nor of a subsequent formation of a high-information interferogram, nor of a subsequent determination of a thickness of the translucent oxide layer. Such a discussion is at pages 194 to 202 of a book entitled “Fourier Transform Infrared Spectrometry” by Peter R. Griffiths and James A. de Haseth. Principals of interferometry are discussed in that book. That book was published by John Wiley & Sons, New York, in 1986. The teaching of that book are incorporated herein by reference.
In the past, when the beryllium oxide region 20 undergoes analysis by a split IR beam, in a nondiffuse reflectance mode, information imputted into an interferogram is restricted to information of the topical features, i. e. the top, of beryllium oxide region 20 .
However, as herein disclosed, when the beryllium oxide region 20 undergoes analysis, by scanning movable mirror of interferometer 25 , in a diffuse reflectance mode, shown in FIG. 5, a more detailed interferogram 50 is produced. This interferogram 50 has more information in it, that is information of the thickness of very thin beryllium oxide region 20 of FIGS. 1 and 6.
In FIG. 6 the angles of incidence of each of converging beams 44 A and 44 B are shown. In FIG. 6, such light incidence angles are shown as forty-five degrees and twenty degrees, respectively. The angle of reflection of rays 45 A, and 46 A has a value dependent on the angle of incidence of beam 44 A. The angle of reflection of rays 45 B, and 46 B has a value dependent on the angle of incidence of beam 44 B. In FIG. 6 such angles of reflection are shown as approximately forty-five degrees and twenty degrees, respectively. Angles of incidence, from ten degrees to eighty degrees, can be used for the disclosed diffuse reflectance Fourier transform infrared spectroscopic method and apparatus.
Although converging beams 44 A and 44 B are shown as being sent onto the oxide region 20 in the apparatus of FIG. 6, nonparallel diverging beams could be sent onto the oxide region 20 , by means of a convex mirror in place of concave mirrir 40 . Diffuse reflected rays produced by the nonparallel diverging beams would also be diverging. These latter diffuse reflected rays could be made to be parallel, by means of a concave mirror, in a similar manner that concave mirror 43 of FIG. 6 collects diffuse reflected rays 45 A, 46 A, 45 B and 46 B and makes them parallel.
Again, an interferogram 50 , that has information of the thickness of beryllium oxide region 20 , is shown in FIG. 7 . The interferogram 50 is a result of IR beams 44 A and 45 A having very different angles of incidence, as they pass into and through the beryllium oxide region 20 and are reflected from the beryllium metal 12 A. The interferogram 50 of FIG. 7 is the same as the interferogram of FIG. 9 A.
A first sideburst 52 of the interferogram 50 is produced as a result of interference of rays 46 A and 46 B. The first sideburst 52 has information of the thickness of region 20 , when first sideburst 52 is taken with centerburst 53 . The first sideburst 52 is shown in FIG. 7 .
In FIG. 7, the first sideburst 52 of interferogram 50 is displaced from the centerburst 53 of interferogram 50 by 10 points. 10 points is proportional to the thickness and average refractive index of the beryllium oxide region 20 of FIG. 6 . This point difference is used to determine the thickness of region 20 . The first sideburst 52 of FIG. 7 is due to interference between the IR rays 46 A and 46 B that are reflected from the beryllium metal subsurface 12 A.
In the initial step of the disclosed thickness measurement technique, reference interferograms of various thicknesses of beryllium oxide, from 25 to 160 microinch thick regions, are used to identify first sideburst 52 . These reference interferograms are used as references against which the interferogram 50 is compared. Interferogram 50 of region 20 is compared against such reference interferograms until a near match is found. The matching technique is described below, to identify first sideburst 52 .
A beryllium oxide region that is somewhat thicker that region 20 , such as a 150 microinch thick region, would increase the distance traveled by the IR beams 44 A and 44 B through such a thicker region.
A reference interferogram 54 , shown in FIG. 7, is produced using a 150 microinch thick beryllium oxide region. A sideburst 55 of reference interferogram 54 is shown in FIG. 7 . Further a centerburst 56 of reference interferogram 54 is shown in FIG. 7 .
In FIG. 7 the reference interferogram 54 of a 150 microinch thick beryllium oxide region, is used as one of the reference interferograms against which the interferogram 50 is compared to identify which arc of interferogram 50 is the first sideburst, that is sideburst 52 .
FIG. 7 shows a subtracted interferogram 58 . The subtracted interferogram 58 is formed by subtracting the value of the reference interferogram 54 from the value of interferogram 50 , at each point along the horizontal axis of FIG. 7 .
A center burst 59 and a first side burst 60 of subtracted interferogram 58 are shown in FIG. 7 . In the preferred initial thickness determination step the shape of the reference interferogram 58 is used to identify first sideburst 52 .
In the final step of the disclosed thickness measurement technique, the distance between first sideburst 52 and centerburst 53 is measured. The measured distance allows one to determine the exact thickness of beryllium oxide region 20 .
The matching technique can be adjusted if the index of refraction of region 20 is not exactly the same as the index of refraction of the beryllium oxide regions that are used to produce the reference interferograms. An adjustment factor can be multiplied by the measured distance to find a second order thickness of region 20 . The adjustment factor would be the refractive index of the regions generating the reference interferograms, divided by the refractive index of the region 20 .
To prove out the interferogram mechanism for an anodic region, numerous thrust plates, and shafts, with a wide range of known oxide regions having thicknesses from 25 u″ to 150 u″, were prepared. Interferograms for these regions are shown in FIGS. 9A to 9 E. These interferograms prove that a sideburst of an interferogram moves away from the centerburst of that interferogram, as the thickness of the region, being measured, becomes greater.
In the disclosed measurement technique, one compares an interferogram of a first order known thickness, with a set of reference interferograms of various regions having known thicknesses, in order to determine a second order known thickness. The range of known thicknesses should include the first order known thickness.
As an alternate first order measurement technique, a thickness value of a known thickness of a standard interferogram that has a sideburst-centerburst distance that is approximately the same as the sideburst-centerburst distance of the interferogram of the unknown thickness, could be taken as the first order thickness value of the unknown thickness.
Several interferograms, made from thrust plates with various thicknesses of beryllium oxide regions are shown in FIGS. 9A to 9 E. Arrows designate the first sidebursts, verifying the proposed interaction of the IR beams 32 A and 32 B with the beryllium subsurface. While a spectroscopist would be able to determine the thickness of the anodization region of any shaft or plate by inspection of the interferometers of FIGS. 9A to 9 E, an automated means of interpreting the spectra was necessary if the technique were to be useful in a production environment.
An implementation plan can be used to determine how the information generated by diffuse reflectance Fourier transform infrared spectroscopy, DRFTIR, can be applied in production. When implemented, the method will find many uses in production in addition to routine oxide thickness evaluation. For example, such uses are:
(1) Nondestructive evaluation of finishing effects and the uniformity of an anodization region; and
(2) Detection of changes in the chemical composition of an anodization region based on refractive index and key absorbances in the infrared spectrum.
Straight specular Fourier transform infrared spectroscopy had previously demonstrated its usefulness in other areas of online production use such as nondestructive gas bearing lube analysis.
Diffuse reflectance Fourier transform infrared spectroscopic analysis of anodization region thickness is another step forward in providing noncontact, nondestructive tools to access important parameters that give meaningful information to the production engineer about manufacturing processes. On-Line DRFTIR implementation can be used, in production activities, for anodize thickness measurement.
The plate and shafts prepared with different coating thicknesses were tested by using diffuse reflectance Fourier transform spectroscopy and a shellscript program, as shown below. A comparison of the coating thicknesses for shafts and thrust plates, as determined by three techniques (DRFTIR, Acid-Etch and Time/Current measurements), is presented in Table 1, as follows:
TABLE 1
Comparison of Anodize Coating Thickness Values By
DRFTIR, Acid-Etch and Time/Current Measurements*
CURRENT/TIME
DRFTIR PROGRAM
ACID-ETCH
Microns
u inches
Microns
u inches
Microns
u inches
THRUST PLATES
0.635
25
0.67
27
0.79
31
1.27
50
1.46
58
1.27
50
1.905
75
1.81
72
1.80
71
2.54
100
2.28
91
2.38
95
3.175
125
2.60
104
2.98
119
3.81
150
3.78
151
3.62
143
SHAFTS
0.635
25
0.68
27
0.71
28
1.27
50
1.26
50
1.45
58
1.905
75
1.80
75
2.10
84
2.54
100
2.89
115
2.84
114
3.175
125
3.04
122
3.05
122
3.81
150
3.96
158
4.11
164
*Site of DRFTIR analysis may not be the same as site where acid etch occurred.
The DRFTIR results agreed reasonably with the acid/etch method, with only two samples showing a discrepancy greater than 10 microinches. The observed differences may by due mainly to the changes in the refractive index of the coating. This seems to be a function of the thickness. Hypothetically, the refractive index of the coating decreases with increasing coating thickness (n=2.1 for 25 microinches vs. n=1.8 for 150 microinches).
An accurate epilayer thickness calculation by the prior art software program was dependent on an accurate value for refractive index as well as an optimal reference thickness. The interferogram for the reference region is subtracted from the sample's interferogram as part of the prior art program, in a manner somewhat similar to that used to produce the difference interferogram 58 as shown in FIG. 7 .
Because the anodization region is so thin, the reference thicknesses had to be very close to the sample thickness, for the the disclosed method to be effective. When working with such thin regions, the prior art program could not discern the position of the first sideburst 52 when using a reference sideburst that was too remote from the sample sideburst. For example, the step of using a 240 u″ reference for a 75 u″ oxide region was not effective in finding the first sideburst. u″ refers to a microinch unit of measure.
In FIG. 8 a gage is shown. The gage is one example of a calibration standard to be used to determine the thickness of the infrared translucent. This gage could be used in the thickness measurement technique. This gage presents the results of the point distance between a first side burst and a center burst of each of several interferograms of FIG. 9 . With this gage one can determine the thickness of a region by measuring the point distance between the center burst and the first side burst of the region's interferogram. One measures the point distance between a sideburst and a centerburst for an interferogram, and compared the point distance to the same point distance on the gage, and reads off the thickness value shown on the gage. This thickness value is taken as the thickness of the region under investigation. Again, one compares that measured distance on the gage, to find a corresponding thickness for that region, on the gage.
The values shown on the gage can be programmed into a computer, as an set of equations that provide thickness over the point range shown in FIG. 8 . Then by putting the measured point distance taken from an interferogram of a region under investigation into the computer, the thickness of the region under investigation will be provided as an output, by the computer.
A shellscript calls out the appropriate reference interferograms and refractive index settings for use in a successive set of exclusion windows. In the first sideburst identity search step, the program gradually searches each window for the sideburst of interferogram 50 that is observed to be closest to the centerburst. When the first sideburst 52 is located, the program calculated the thickness of the beryllium oxide region, e.g. region 20 , and reports the thickness of the beryllium oxide region.
If the operator has a general idea of the thickness of the beryllium oxide region and inputs the information into the FTIR computer when asked by the shellscript program, the computer will determine if the appropriate first sideburst for that thickness is present in the corresponding exclusion window, within two minutes. If the first sideburst is not observed, the program informs the operator that the proposed thickness is inaccurate and asks if the operator wants to proceed with the determination of the true thickness. This takes about fifteen minutes while the computer searches through each exclusion window. The program gives the operator control over the direction of analysis.
While the present invention has been disclosed in connection with the preferred embodiment thereof, it is understood that there may be other embodiments which fall within the spirit and scope of the invention as defined by the following claims. | A method for producing an interferogram of an infrared translucent layer that is on a reflective substrate, comprising generating parallel infrared interferometer beams by means of an infrared interferometer, converging the parallel infrared interferometer beams into converging infrared interferometer beams, sending the converging infrared interferometer beams onto the infrared translucent layer to produce diffusely reflected infrared interferometer rays from above and below the infrared translucent layer, and making the diffusely reflected infrared interferometer rays into parallel reflected infrared interferometer rays. | 6 |
This application is a division of application Ser. No. 516,714, filed 7/25/83, now U.S. Pat. No. 4,606,008.
BACKGROUND OF THE INVENTION
In commercial, industrial and domestic applications it is often useful to determine quickly the position, speed or direction of rotation of a movable body such as a meter hand, a robot arm, or perhaps an abnormality in a plate of dielectric material. For an example of the former, various means have been developed for determining the position of the dial hands of utility meters so as to permit them to be read rapidly and automatically from a remote location. In contrast with conventional practice in which a utility company employee periodically visits each meter to obtain a visual reading, remote meter reading offers very significant economic benefits. By suitable means, for example, all the meters in a large apartment complex can be read in a few seconds from a single location outside the building or in the basement; or meters can be read several times daily to allow the utility to obtain energy flow data, study consumption patterns, or (by the use of time-of-day rates) discourage consumption during periods of high demand.
Clearly, in such a reading means a highly desirable feature is the ability to read ordinary utility meters which are already in service. Nonetheless, with the exception of previous work by and on behalf of the assignee of this application, remote meter dial reading has been generally possible only through the use of expensive specially-equipped meters which replaced the ordinary meter already in use. The above-mentioned previous efforts by and on the part of the assignee have resulted in meter-reading systems disclosed in U.S. Pat. Nos. 3,500,365, 4,433,332 and 4,007,454; and in U.S. patent application Ser. No. 375,919, filed May 7, 1982 and now abandoned. In each of these patents and applications, in general, a sensing transducer scans the dials of the meter by inducing an electric or magnetic field which includes the hands. The theory of the aforementioned patents and applications is that the transducer's field can be coupled to the meter hand through the intervening space, and variations in the phase of the resultant signal detected give an indication of the meter hand's position. Because no mechanical parts that move relative to one another are used, potential problems of maintenance and reliability are eliminated.
Improvements to the devices disclosed in the above-mentioned patents and applications are also disclosed in U.S. Pat. No. 4,429,308 assigned to the assignee of this application. This application is directed to a peculiar shape of the field-producing electrode which provides improved uniformity of angular sensitivity. Also, a further improvement is disclosed in U.S. Pat. No. 4,214,152, issued July 22, 1980, which involves a technique for compensation for the mechanical misalignment of one of a plurality of meter hands by adjusting the reading of a more significant hand responsive to the hand position of the adjacent lesser significant integer.
SUMMARY OF THE PRESENT INVENTION
The present invention is also directed to a method and apparatus for detecting the presence and/or position of objects causing a disturbance to the field of such a phase-sensitive transducer, wherein the transducer is a prescribed circular array of electrodes (or in the magnetic approach, a circular array of pole pieces). While the present invention may be adapted to other applications such as the determination of the position of the arm of a robot or the location of openings or flaws in a planar workpiece, for the most part the invention will be described herein as being utilized for the determination of the position of a meter hand, keeping in mind that the techniques of the invention are equally applicable to other areas.
In contrast with conventional phase-measuring techniques, typically concerned with directly-measured timing relationships between sinusoidal signal waveforms, one aspect of the present invention permits a more accurate determination of phase and hence of hand angle, from the measured amplitude ratios of a plurality of periodic, stepwise signal levels. Stepwise levels arise from the use of certain properties of square waves by a novel field-excitation approach utilized in this invention. By these means it has been found possible to simplify manufacture and eliminate errors which are often introduced by waveshape imperfections in earlier, sinusoidally-driven models of the transducer described above. Further, according to a second aspect of the invention there is provided an accurate calculation of the quality of the phase-related signal from the amplitude relationships between periodic, stepwise signal levels without the necessity for difficult measurements of complex, continuously-varying waveshapes. Moreover, and in accordance with a third aspect, the present invention allows rapid compensation for the effect of varying distance between the transducer and the hand, increasing the span of distances over which the transducer can be satisfactorily operated, reducing its cost, and simplifying its installation on the meter. Further, the present invention employes a novel technique for converting the numerical results of the transducer's reading process into standard ASCII code: this aspect of the invention accomplishes the desired conversion faster and with less computational hardware than is otherwise possible.
More particularly, in accordance with the first aspect of the present invention, the drive, array, and detector system to be herein described produce a resultant cyclic signal of six steps repeated over and over in time. The signal is periodic, and a complete cycle of six steps is equal to 360° of phase angle or 2π radians. The six steps occur at fixed times after the transition of the reference phase (i.e. at 0, π/3, 2π/3, π, 4π/3, and 5π/3 radians). The six-step levels are transferred through a digital logic controlled sample and hold gate so that they may be acquired by the system microprocessor with an analog to digital (A/D) converter with a variable gain prescaler. The signal is then analyzed for quality and, if acceptable, is used to calculate the hand angle.
In general the signal is produced by generating a plurality of phase modulated drive signal pairs, each pair consisting of a signal and its complement. Each of the drive signals is a plurality of two-phase square waves of the same amplitude and frequency, and the transition of all drive levels occurs synchronously. For a prescribed period of a given number of cycles (N), each drive signal changes phase by 180° each N/2 cycles. Also in the same period of N cycles, where K equals the number of drive signals, each phase shift occurs N/K cycles subsequent to the phase shift of the previous drive. The period of N cycles is so selected such that 2N/K is an integer. Each of the aforementioned drive signals are fed to a separate electrode in the electrode array in such a manner that each signal and its complement are fed to diametrically opposed electrodes. The relationship of the phase progression of the drive signals is proportional to the angular relation of the electrodes. The drive signals are coupled (capacitively or permittively) to a central node through the meter hand in such a manner that the algebraic sum of each drive signal pair is constant in the absence of any variation (meter hand). In the presence of a variation (meter hand) the algebraic sum of each drive signal pair varies at the same frequency as the drive signals, so that the signal on the central node is the superposition of the algebraic sum of all drive signal pairs.
The resultant signal on the central node is sampled by generating a synchronous gating pulse at a time betwen transitions of the drive signals. The gating pulse is relatively short (of a duration less than one-half the duration of the drive signal period) and at the same frequency as the drive signal, so that the resultant synchronously detected signal is in the form of a multi-step signal in the which the number of steps is equal to the number of drives. The resulting synchronously detected signal is then a multi-step approximation to a sine wave in which the phase angle between the sine wave and a timing point (phase transistion of a given drive signal) is proportional to the angular position of the dielectric variation (meter hand) confronting the transducer.
According to the second aspect of the invention, the hand angle is then calculated utilizing the six step cyclic signal. First, the six steps are converted into terms representative of the imbalance of the drive signals, which terms are vectors spaced 120° apart (hereinafter referred to as vectors A, B, and C). While the six signals could be converted directly to two orthogonal vectors, it is preferred to first determine the three vectors of A, B, and C to facilitate tweaking of the system (obtaining a balanced or net resultant zero signal in the absence of a hand). The three phases are then combined as vectors into two orthogonal vectors, I and J. The algebraic (+ or -) signs of I and J are used to determine in which quadrant the phase of the signal lies (keep in mind there are four quadrants in 2π radians). The size of vector I versus vector J is then compared to determine whether the resultant vector is within π/4 (45°) of the I axis or not (whether J/I is greater or less than 1). The ratio of J and I is then the tangent of the resultant vector. The arctangent of J/I is determined through a successive approximation routine with proper adjustment for quadrant and proximity to the I axis.
The above technique for determining J/I is utilized to determine the phase angle of the hand position which is then converted to a binary representation thereof. According to yet another aspect of the invention the amplitude of the sine wave approximation is utilized later in the calculation process to make a compensation on the resulting hand angle value based on the distance of the transducer from the meter hand. When the meter hand at "zero position" is spaced some distance from the transducer, the calculated 0 may not actually coincide with the actual or physical 0. Therefore a predetermined compensation value is added to the signal representing the hand position, which value is a function of the distance between the hand and the electrode array. This distance is correlated to a change in signal amplitude. The amplitude based correction is made utilizing a lookup table.
In accordance with another aspect of the invention the revised or corrected signal is then further compensated to provide for mechanical misalignment of hands, which is referred to as an Inter-Dial Compensation (IDC). In meter reading devices of the type described hereinabove, a problem may arise because of mechanical inaccuracies in the meter. As will be well recognized, most meters which must be read constitute a plurality of dials (or hands) which represent, for example, kilowatt hours, tens of kilowatt hours, hundreds of kilowatt hours, and thousands of kilowatt hours. In some cases the hands are not accurately aligned with the numerals on the dial face. For example, when the reading of the kilowatt hand is at 2, having just passed 0, the tens of kilowatt dial should be 2/10 of the digital distance beyond one of the integers thereon, for example, 0.2. Due to misalignment, however, the tens of kilowatt dial may, for example, be pointing in a direction which would apparently be reading 9.9. If the dial readings are obtained independently, errors then can clearly be carried through the system.
To correct or compensate for the possible misalignment of certain hands or dials, the present invention introduces a technique whereby the least significant dial is read first and then a compensating offset value is generated for the next dial. For each reading of a dial after the first, there is automatically added a correction factor to the apparent value of the indicator being read which is based on a cumulative correction factor from the previously adjusted values of all lesser significant indicators. The compensation value is continuously adjusted responsive to the reading from the lesser significant dials, so that the adjusted reading from any selected more significant dial will tend to fall exactly halfway between two adjacent integers. The compensation adjustment continues from each less significant dial to the next more significant dial as a cumulative adjustment factor, so that when the reading is completed, errors due to mechanical misalignment should be eliminated.
As previously stated the phase angle of the hand position is converted to a binary representation thereof. In accordance with the present invention the conversion is effected by utilizing binary coded integers whose range is so selected as to facilitate calculations and compensations and to provide a resulting value that readily converts to the BCD of the integer value of the hand position. The key to this special range is that the circle is first broken into 640 parts. That means that each quadrant includes 160 parts and each half-quadrant has 80 parts. These are important considerations in determining the arctangent of the phase angles of the hand, which will be converted to a number between zero and 639.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a timing diagram of a pair of phase shifted drives;
FIG. 2 is a schematic representation of a simple conventional single-sided detector circuit which could be used with the present invention;
FIG. 3 is a schematic representation of a more reliable double-sided differential detector circuit used for synchronously detecting the output signal from the transducer plate;
FIG. 4 is a timing diagram representation of a single sine wave drive synchronously detected by a pair of sampling gates;
FIG. 5 is a timing diagram representative of a square wave drive signal as used in the present invention demodulated by a single gate resulting in a simple square wave;
FIG. 5a is a plan view of the electrode arrangement contemplated by the present invention;
FIG. 6 is a timing diagram representative of the relation of the drive signal pairs according to the present invention;
FIG. 6a is illustrative of the signal received from the central node and its subsequent synchronous detection;
FIG. 7 is a representation of the six step signal generated by synchronously sampling the signal from the central node in accordance with the present invention;
FIG. 8 is an electrical block diagram of the six step acquisition system;
FIG. 9 is a diagrammatic representation of the detected signal separated into its three components;
FIG. 10 is a graphic representation of a quadrant diagram showing the I and J vectors with 45° bisectors;
FIG. 11 is the arctangent lookup table;
FIGS. 11a and 11b together form an electrical schematic of the circuit for amplifying and synchronously demodulating the signal from the transducer plate central node;
FIG. 11c is the amplitude compensation lookup table;
FIG. 12 is a major block diagram of the system of the present invention;
FIG. 13 is a functional block diagram of the generation of the drive and sample signals;
FIG. 14 is a block diagram of the gates, carrier and system clock generator circuit;
FIG. 15 is a block diagram of the phase modulation signal generation portion of the system;
FIG. 16 is a block diagram of the phase modulator and transducer drive logic portion of the system;
FIG. 17 is a block diagram of the sample and hold logic for synchronously sampling the steps of the demodulated signal;
FIG. 18 is a program flow chart interfacing the sample and hold digital logic with the central processing unit;
FIG. 19 is a block diagram of the baud rate generator;
FIG. 20 is a block diagram of the 5-bit shift register which controls the dial-enable function;
FIG. 21 is a program flow chart of the interdial compensation technique; and
FIG. 22a thru 22q are program flow charts of the system of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed to a transducer system which utilizes a set (six) of phase-modulated electrical drives and a double-sided synchronous detection system to detect the position of an object having electrical characteristics which differ from the characteristics of the surrounding medium, as for example, the position of a meter hand. Phase, of course, is the temporal relationship of two periodic phenomena, such as electrical signals in the present invention. Phase is measured in terms of a portion of a complete cycle of one of the signals. Thus, one cycle equals 360° or 2π radians. In order to measure time differences or phase, some standard point or landmark must be used. Since the signals may be square waves, as well as sine waves, the peaks are not generally used as the landmark. Rather, a conventional technique which has developed for measuring phase relationship is to utilize the positive-going zero crossing point, with zero defined as a level midway between the high and low extremes (FIG. 1). This is referred to as the "zero crossing technique" and is well known. Another known technique for generating a phase landmark is the "phase locked loop" technique.
By way of background leading up to a discussion of the present invention a phase demodulation system will be outlined. Assume that A is a reference gating pulse, which synchronously gates or generates samples from another periodic signal S for some period, ΔT. The mean level then of the sampled signal is a function of the phase angle, θ, between the two signals, although not unambiguously so. A simple single-sided sample and hold circuit for performing this task is shown in FIG. 2.
Obviously, some information will be lost in that only a brief portion of the signal is sampled. A second synchronous gating pulse B can be generated 180° delayed from the gate pulse A. If a signal S is sampled again with pulse B, and the resultant signal is inverted and added to resultant signal generated by pulse A, then there results a "differential detection system" which achieves two ends: (a) the effective signal is doubled; and (b) shifts in the DC or low frequency level of the signal are cancelled out, producing a more reliable signal (E) with consequent rejection of a common DC or low level component (this is termed "common mode rejection"). The circuit for producing such a differential detection signal is outlined in FIG. 3. This circuit also amplifies the resulting signal.
Thus, where there is a signal S sampled by gating pulse GA, and the phase difference between the signals and the gating pulse GA changes smoothly, then the sampling window moves smoothly through the entire cycle of the signal, tracing out the signal at an expanded time scale (FIG. 4). This may be thought of as a beat frequency, f E , determined as: f E =(f GA -f S ). This holds true for both single- and double-sided sampling cases. If f GA and f S are known, then f E is also well known. If signals GA and S both commence with a certain phase relationship, they will return to that phase relationship after a calculable number of cycles according to the following equation: ##EQU1## A new "supra" time period is thus defined (FIG. 4), which is required for θ (the phase relationship between GA and S) to cycle 2π radians. Again, the signal E is related to the phase θ between signals S and GA. Therefore, if a reference signal R with a period of ##EQU2## exists, a new phase angle φ can be defined as the relative phase of S (relative to GA) and R (relative to E). Since θ is the phase of S with respect to GA, then φ is related to θ in such a manner that if θ is determined as the zero-crossing of R, then φ=θ (it should be kept in mind that φ is the phase angle of the phase of E at the zero-crossing of R).
A periodic signal, S A , can be generated (FIG. 1). A second signal, S B , is generated which has the same frequency as S A , but is phase shifted ρ with respect to it (see FIG. 1). If a signal is detected which may be either S A or S B , then it can be determined which signal it is by examining φ with respect to the reference signal. If φ=0, the signal is S A . On the other hand if φ=ρ, then the signal is S B . Mathematically if two sine waves are added together, a single sine wave results defined by the following equation:
C sin (ωt+Ψ)=A sin (ωt)+B sin (ωt+ρ).
The addition in the above equation is of a vectorial nature. The important consideration is that a single sine wave with a phase angle of Ψ results. The angle Ψ is a function of ρ and the ratio of A to B. If ρ is known (i.e. fixed), then ρ is a function of the ratio of A to B (vector addition). Therefore, if Ψ can be measured, then there results a measure of the ratio of A to B.
If one has a system which differentially couples S A and S B according to the position of some object (meter hand), then the position of the object can be determined from Ψ. The situation with two signals with different phases can be expanded to include more than two phases. Thus, if the signal phases are arranged in an orderly and predictable manner, three drivers can be used unambiguously to determine the position of a rotatable hand. If three equal-amplitude sine wave signals were equally spaced over 2π radians at 2π/3 intervals, when summed, the vector sum is zero. The above analysis is conventional and should be used as background for the present invention, a description of which ensues.
Drive Signals of the Present Invention
The present invention uses a phase modulation/demodulation technique to generate a resultant signal which is the superposition of a set of square waves. The drive signals are not sine waves, but are phase modulated square waves with two levels, V DD and V SS . Only two phase conditions of the carrier signal of each of the drives are used. The drive signals have two possible phase transition points: 0 and π radians (0° and 180°). Each drive has a 50% phase cycle (1/2T at 0 and 1/2T at π). A single drive S synchronously demodulated by a single gate GA results in a simple square wave E (FIG. 5).
By driving square waves which have only two phases 180° apart, the gate can have a long sample period. The gate is not closed until all transients have died out or been suppressed. Thus the concept is well suited to digital implementation.
In the present invention, there is utilized drive pairs consisting of driver signals and their complements. Three such pairs of signals are used. One pair (A, A) phase transitions at 0 with respect to a reference signal. Drive signal A assumes what is arbitrarily termed the 0-phase condition at 0. A second phase pair (B, B) transitions at 2π/3 (120°) with respect to the reference signal. A third phase pair (C, C) transitions at 4π/3 (240°). The above are referred to as phase modulated drive signals. The driver array electrodes are physically arranged (FIG. 5a) at such angular positions which correspond or correlate with the phase of their phase shift with respect to the reference signal. Thus:
______________________________________ PHYSICAL ANGLETRANSITION OR OF ELECTRODESDRIVE PHASE ANGLE RADIANS DEGREES______________________________________A 0 0 0°.sup.--C 1/3π 1/3π 60°B 2/3π 2/3π 120°.sup.--A π π 180°C 4/3 π 4/3 π 240°.sup.--B 5/3 π 5/3 π 300°______________________________________
This arrangement is also shown in FIG. 6.
In such arrangement in the absence of a hand or other dielectric variance, all phase pairs should balance, and there should be no signal on the center node or center electrode. The presence of a meter hand unbalances the coupling of the drives to the center electrode. If only signals A, B, and C and not their complements were present in the two-phase square wave condition, a non-zero signal would result. The output signal on the center electrode is strangely shaped (FIG. 6a). However, once it is buffered and synchronously detected as described in FIGS. 11a & 11b the resulting signal has six steps which always occur at the same places, although the levels will change as the position of the hand changes (See FIG. 7). From FIG. 6 it is seen that there are six different phase conditions, thus the "six step output." Each step, however, does not correspond to one of the six electrodes. Note that steps 1 and 2 are not adjacent but are symmetrically offset from the horizontal center line. It is the nature of such a periodic function that, in the absence of any perturbing factors, each step will have its symmetrical partner. The steps (FIG. 7) have been numbered to show this fact. The actual step levels will, of course, vary according to the actual position of the hand in front of the array.
Once the six-step signal has been generated, there are several methods of determining the hand angle. The signal can be filtered to a sine wave and the zero-crossing detected, as described hereinabove. If a counter is started at θ=0 and turned off by the zero-crossing detector, the count value is related to the phase angle. Similarly (and perhaps more reliably) a phase-locked loop can produce a square wave whose zero-crossing is closely related (offset by π/2) to the signal phase. This signal can be used to stop a counter as with the zero-crossing detectors. While either of the above types of detector may be used, it is preferred that the phase angle be calculated directly from the six-step signal levels in accordance with the techniques described hereinbelow.
Calculation of Phase Angle
The calculation of the phase angle of the signal directly from the six-step levels requires reading the step levels with an analog-to-digital converter and then performing an algorithm (FIG. 8). Contrary to the zero-crossing technique, this technique is not subject to component value changes. Additionally, the calculation method makes available a subsequent compensation based on the amplitude of the signal, which compensation will be related to the hand-to-transducer spacing. The calculation method is readily achieved with a microprocessor or microcomputer, although the method is compatible to a hardwired logic circuit.
The microprocessor must have some sort of data base representing the levels of the six steps, if it is to generate a hand position. In the system of the present invention, no negative voltages are used, although this is not a requirement. The signals have a center voltage of some value V, with the steps being either greater or less than V. In conjunction with the generation of the signal, there is utilized an 8-bit analog-to-digital converter to measure the levels and convert them into a digital representation in binary language. Due to the large variation in signal amplitude which results from the ordinary range of array-to-hand spacing, 10 bits of resolution is actually needed. To solve this problem there is utilized a variable gain prescaling amplifier in front of the step level acquisition circuit. (See FIG. 8). This amplifier can have a gain of 1, 2, 3, or 4, all under the control of the microprocessor. The system is designed so that the voltage level V is in the center of the A/D converter range (the 8-bit range is 0-255, so the center point is at 127), thus the signal is at V+ or - the step amplitude.
The step levels are acquired in the following sequence:
1. Gain is set to lowest level (1).
2. Levels are read in the order 1, 2, 3, 4, 5, 6.
3. Maximum and minimum levels are found (i.e. levels 3 and 4 in FIG. 7.
4. The gain (G) is set such that the signal is as large as possible without overflowing the A/D range.
5. The levels are reread in the same manner as step #2, above.
As stated above, and illustrated in FIG. 8, the levels are read into the microprocessor with an analog-to-digital converter. This device converts a voltage level into a binary code. An 8-bit A/D converter can resolve a voltage into one of 256 levels (2 8 ). As stated hereinabove, since 10-bit resolution is needed (1024 levels), the other 2 bits are generated with the variable gain preamplifier, which has an integer gain of from 1 to 4 (2 2 ) and is controlled by the microprocessor. The relationship of the signal acquisition elements is diagrammed in FIG. 8. The digital logic circuit controls the timing of the gate closing so that the proper six-step level is sampled at the proper time. The six steps are acquired in the order described hereinabove to have the maximum time available between samples to allow the A/D converter to perform its function and because the steps will be analyzed in pairs in the order taken into the A/D converter. After step 5 hereinabove, the six-step levels have been acquired in a digital form (binary code), and the gain being utilized has been stored. The same gain is used for all six steps. This is because the actual calculation of the hand position to follow is a function primarily of the ratios of the levels. The absolute amplitude is only critical in applying the amplitude compensation value, and does not require great precision. As this system is ratio based in most of the algoriths involved, while it required 10-bit resolution, only 8-bit accuracy is required. Thus, larger tolerances can be tolerated in the amplifier gain.
The microprocessor or embodiment of the algorithms has several reliability checks built thereinto. For example the algorithm checks the time required for the A/D converter to respond with data. If more than a specified amount of time is required, the microprocessor or algorithm presumes a fault condition and attempts to read the dial over. If there is a failure to respond the second time the system goes into a fault mode and does not attempt to read the dial in question or any subsequent dial. The algorithm also checks certain characteristics of the six-step levels. If the signal is too large (i.e. six-step levels which deviate too much from ±127.5), such signals will be too close to 0 or 255. This might cause the levels to be higher than the voltage which corresponds to 255, and then the A/D output would clip or limit, resulting in a "0" output. If the level is too low, the A/D output would tend to stay at 0. If the A/D level is too close to 0, then, the microprocessor presumes that the signal has either too high a voltage or too low a voltage, and it makes no difference which, as the result will be the same. The microprocessor steps through each of the stored six-step levels and checks to make sure that all are above some minimum value. If they are below that value, the entire set of values is rejected and the system attempts once again to read the six steps, going back through the gain setting part of the program. If the result is again faulty, the system presumes something is wrong and goes into the fault mode.
Each pair of steps (1 and 2, 3 and 4, 5 and 6) should be symmetrical about the center line. If they are not, it is presumed that some sort of noise got into the system or that there is a problem someplace in the electronic circuit. In either case, the signal is not acceptable. The symmetry of the step pairs is tested by summing the pairs together, which sum should equal 255. If the sum deviates from 255 by more than some specified amount the data is presumed to be faulty and the system tries to reread the steps. Again, if the second rereading fails, the system goes into the fault mode. The test is quite powerful and useful.
A test for too low a signal level is made later in the program during the amplitude compensation operation, as the signal level must be determined. If the signal is too low, the calculated hand position may be influenced by some residual or spurious signal and not due to the hand, so the system goes to the fault mode. These system checks do much to prevent a faulty reading from being transmitted.
Reduction to A, B, and C Vectors
As stated hereinabove, the six stepped signal at the central node is the superposition of three synchronously detected, square wave drive pair imbalances:
A=(h.sub.1 SA+h.sub.2 SA)
B=(h.sub.3 SB+h.sub.4 SB)
C=(h.sub.5 SC+h.sub.6 SC)
In the absence of a hand, we want A=B=C. Alternatively in the absence of a hand we want h 1 =h 2 , h 3 =h 4 , and h 5 =h 6 as h 1 thru h 6 are coupling variables reflecting the coupling between the center electrode and each component of the square wave devices due to the presence of the hand. It should be recalled that drive signal SA is the inverse of drive sign SA, etc. The presence of the hand causes the drives to be unequally coupled to the center electrode in the array, and hence, the ratio of imbalances is a function of hand position. If each of the phase pairs are synchronously detected separately, with each pair unbalanced to the same degree such tht SX>SX, there would result three square waves 120° apart (See FIG. 9).
The six steps are generated from the sum of these pairs such that:
S1=+A-B+C 1.
S2=-A+B-C 2.
S3=+A-B-C 3.
S4=-A+B+C 4.
S5=+A+B-C 5.
S6=-A-B+C 6.
In the above analysis S1 is step 1, S2 is step 2, etc., as reference to FIG. 7. The next step of the calculational technique is to take the six-stepped signal data and determine vectors A, B, and C. Since the six-stepped signal is symmetrical about the center line voltage, the step difference terms (SDX) can be defined to remove any small offset there may in the data. Thus:
SD1=S1-S2
SD2=S3-S4
SD3=S5=S6
If the above two sets of equations are then solved, the three drive waves appear as follows:
4A=SD1+SD3
4B=SD3-SD2
4C=SD1-SD2
Note that in all cases, the term "4×" appears, which is four times the vectors that are being solved for. The results, 4×, have the potential of being 9-bit values as each SDX has 8-bits resolution. There is no reason to divide the result by four, as that would reduce the precision. Thus, the valves are redefined:
A=4A
B=4B
C=4C
The values A, B, and C have now been calculated and can be treated as vectors 120° apart. Since A, B, and C are all 9-bit values, they can no longer be kept in 8-bit registers, therefore, they are maintained in 16-bit registers (two 8-bit registers). This allows signed calculations to be accomplished using the 2's complement method, which is easier in a microprocessor. Since 16-bit registers are now being utilized, the valves can be normalized for preamplifier gain. This is done by multiplying each step difference (SD) by 4 and dividing the result by the gain G. To multiply by 4 in a microprocessor, the contents of the register are simply shifted to the left two places.
Calculation of I and J Vectors
It should be noted that the three vectors (A, B, and C) define, and actually overdefine a resultant vector. The algorithm, as implemented in the microprocessor reduces the A, B, and C vectors to a single vector at some angle with some magnitude. This is done through consolidation first into two vectors which are at right angles to each other. Traditionally, I and J are defined as unit vectors which are orthogonal (90° or π/2 radians apart). Such vectors are the x and y axes in Cartesian coordinates. Mathematically, I and J are calculated as follows:
I=A-(B+C)/2
and
J=(B-C)×((√3)/2)
The calculation of I is straightforward and needs no explanation; however, the calculation of J utilizes a simplifying approximation for use in the microprocessor. Since (√3)/2=0.866 and 111/128=0.867 therefore: (√3)/2 is approximately equal to 111/128. This considerably simplifies things, as (B-C) can be multiplied by 111 and then divided by 128. Dividing by 128 in the microprocessor is done simply by shifting 7 binary digits to the right. The multiplication by 111 requires that a 24-bit wide results register be used on a temporary basis.
I and J have now been calculated on a signed basis. The next step is to separate the signs from the values, converting the values into absolute values with the signs stored as separate sign flags (SI for the sign of I and SJ for the sign of J for later use). To facilitate later calculation of the signal amplitude, two new variables are created which are I and J with reduced resolution so that the resulting values will fit into 8-bit registers, keeping in mind that I and J are, at this instant, 11-bit values. This step is easily done by shifting the values from I and J three bits to the right. All is now ready for calculation of the hand position.
Raw Count Generation
It is now desired to convert orthogonal vectors I and J with their sign flags into a hand position. For reasons that will become clear later, the circle is divided into 640 parts or counts (which are called Wason Counts or WC's). The angle of the resultant vector is defined by (signed) I and J using the arctangent. This calculation is broken into two parts: first, finding the angle with respect to the I axis, then finding the quadrant in which the angle lies. In FIG. 10 there is illustrated a conventional labeled quadrant diagram with 45° bisectors.
As is well known the tangent of any angle is the ratio of J to I (TAN θ=J/I). Thus, to find the angle θ, it is necessary to determine the angle whose tangent is J/I (arc TAN J/I). Where I is equal to or greater than J, this is no particular problem, however, where J is greater than I, then θ=90°-Arctan (I/J). When I equals J, θ equals 45°. Thus, each quadrant can be broken into two parts. The quadrant is determined by the signs of I and J, which have been stored as SI and SJ, the sign flags. The quadrant is then determined as follows:
______________________________________SI SJ Quadrant______________________________________+ + I- + II- - III+ - IV______________________________________
First, the microprocessor program determines if I is less than J, a swap flag (SF) is set and I and J are switched. The microprocessor then finds and equivalent to the arctangent of J/I. Since the circle has been arbitrarily, but with ultimate purpose, divided into 640 parts, 45° is equal to 80 counts. Thus, the arc-tangent is in non-standard units. By virtue of the process, J is always less than or equal to I, hence a simple division would result in a value less than or equal to 1, a value not suited to integer arithmetic. Thus, the J value is multiplied by 256 by shifting it 8 bits to the left. This is done by concatenating (joining or linking together) an 8 bit word of zeros to the right. Thus, when J is divided by I, the resultant answer will be a value ranging from 0 to 255, a suitable range for binary logic. The tangent equivalent K is now calculated (K=256×J/I). This value can be converted into angular equivalent units utilizing a sucessive approximation procedure.
Successive Approximation of the Arctangent
The tangent equivalent K is converted into angular equivalent units (WC's) through the use of a successive approximation algorithm which utilizes an 80 point sequential table. The table is generated by the following simple BASIC program:
100 PI=3.141592654: REM===CREATE LOOK UP TABLE===
110 D=2×PI/640
120 DIM VA(79): REM===DIMENSION ARRAY===
130 PRINT TAB (6); "W"; TAB(15); "INTEGER"
140 FOR W=0 to 79
150 T=D/2+(WxD): REM===HALF-WAY BETWEEN W'S===
160 LU=256xTAN(T)
170 VA(W)=INT(LU+0.5): REM===ROUNDOFF TO INTEGER===
180 M1=7-LEN(STR$(W)
190 M2=20-LEN(STR$(VA(W)))
200 PRINT TAB(M1); W; TAB(M2); VA(W)
210 NEXT W
220 END: REM===END OF LOOK UP TABLE CREATION===
W=angle in WC's (remember, 2π=640WC's)
T=an angle half way to the next W
VA(W)=integer value of K
This results in a table of values set forth in FIG. 11 of the drawings.
Successive approximation is a process of converging on a value or solution by making a series of guesses within a set of rules. Two limits are defined, an upper and lower limit; the designated value is then compared to the value stored in the register midway between the upper and lower limits. If K is greater, then the midpoint becomes the new lower limit. Conversely, if K is less than the midpoint, then the midpoint pointer becomes the new upper limit. The process is repeated until a single value is converted upon. The following variables are defined:
K=Our calculated arctangent equivalent
WP=Current center pointer and final output word,
UP=Upper pointer,
LP=Lower pointer,
VA(XP)=Value in register at the pointer location X.
Keeping in mind that the goal is to determine the WP, the following procedure is used in a successive approximation subroutine (SAS):
1. If K<1, then WP=0, then exit SAS
2. If K>253 the WP=80, then exit SAS
3. Set UP=79
4. Set LP=0
5. Set WP=(UP+LP)/2 (take integer value)
6. Get VA(WP)
7. Is K>VA(WP)?
A. If yes, LP=WP (Redefine lower pointer)
B. If no, UP=WP (Redefine upper pointer)
8. is (UP-LP)>1?
A. If yes, then return to #5 above
B. If no, then WP=UP, then exit SAS.
Note that there are three places that the subroutine can be exited: after step 1, after step 2, or after step 8B. In any of these three cases, WP is defined. The maximum number of times that it is necessary to go through the loop defined by steps 5 through 8A is seven. This is a very efficient method of searching through the table of arctangent values to find the one which most closely approximates K. The "address" (WP) of the value is the angular equivalent needed to proceed with the calculation of the hand position.
Sector and Quadrant Selection
Earlier in the processor program, there was stored a value (SF) to indicate whether or not the I/J vectors had been swapped. That value is now used to determine which sector of the quadrant (FIG. 10) WP is in. In all cases, if the I and J values were not swapped, WP lies in the sector closest to the "I" axis. Conversely, if a swap of I and J was made, the resultant vector or WP lies in the sector closest to the "J" axis. The rules are simple. If the swap flag (SF) is clear, then WP=WP. Conversely, if the SF is set, then WP=160-WP.
Now the vector can be placed in the proper quadrant and the value of W calculated with a decision tree based on the signs of I(SI) and J(SJ):
If sign of SI is + (or zero) and:
If sign of SJ is + (Quadrant I), then W=WP, exit
If sign of SJ is - (Quad. IV), then W=640-WP), exit
If sign of SI is - and:
If sign of SJ is + (Quad. II), then W=(320-WP), exit
If sign of SJ is - (Quad. III), then W=(320+WP), exit
There has now been determined a value W which is in the range of 0 to 639. Before being converted into a final dial digit reading, some compensations must be applied.
Compensations
On the value W which has been determined as being representative of the hand position, there are now three types of compensations to be performed. Those are offset, amplitude, and inter-dial compensations. Various factors cause W not to be 0 when the hand is apparently in a 0 position. That is, the relationship between W and the true hand position may have some deviation. One type of deviation may be that, because of manufacturing considerations the physical layout of the electrode array is such that when the hand is in the 0 position, the calculated value W is offset by some fixed amount, which also applies to all values around the dial. This is referred to as an "offset" compensation and is adjusted through a baseline adjustment. Another type of deviation which may occur is a function of the distance between the hand and the array, called the "z" spacing to correspond to the traditional Z axis in a polar coordinate system. To compensate for the "z" effect an adjustment value, based on the signal amplitude, is applied to the detected signal W. Finally, each dial reading must be adjusted so that information from the previous dial readings are used to reduce or remove effects of small errors in hand alignment (physical alignment) or electronic process (noise and non-linearity). This is referred to as "inter-dial" compensation and will be discussed hereinafter.
Offset compensation is a baseline correction for the gross rotation of the array pattern. The calculated hand positions have an average offset from the true hand position. This offset is adjusted by adding a constant value (OS) to the detected signal count W. Therefore, W=W+OS. The offset compensation value is generated when the amplitude compensation table is generated, as OS defines a starting point to be used on the amplitude compensation curve.
Amplitude Compensation
The offset changes as the spacing between the hand and the array changes. Fortunately, the amplitude of the six-step signal is a function of the spacing between the meter hand and the driven array. It has been found that the relationship between the offset and the amplitude (RA) may be approximated with the following equation:
Total Offset=a+b(RA)+c(1/RA)
a, b, and c are constants which are generated from experimental data. This experimental data involves generating amplitudes (RA) and uncompensated W's at a number of known hand positions at a number of known spacings (z's). From these values the constants a, b, and c are generated by multiple regression techniques.
The total offset could be calculated directly; however, it would require a considerable amount of memory space and time in the microprocessor based system, so a lookup table is used. The amplitude is calculated from vectors I and J as follows:
RA=√(I.sup.2 +J.sup.2).
Both I and J are 11-bit values, hence squaring and summing them results in a 22-bit value. This is too cumbersome to work with, so rather than using the entire amplitude RA, a truncated version of the amplitude is used. Recall that a truncated version of vectors I and J (referred to as IV and JV) were generated earlier in the process. These are both 8-bit values, and now there is defined a new value RS which is the sum of the squares of these values, has a maximum bit size of 16, and is always positive.
The range over which the amplitude compensation is to be performed is selected and the offsets are calculated at points midway between the adjacent values on a lookup table. Instead of the equation using RA, there is generated an equivalent equation using the square root of RS. Thus,
Total Offset=a+b(√RS)+c(√RS)).
This equation is solved for RS as a function of total offset (TF), a, b, and c with the following result:
RS=[(((TF-a)+((a-TF)-4bc)))/(2b)].sup.2
From the results, there is generated a list of values of RS as a function of TF at intervals which are used in the lookup table. The minimum RS value permitted was selected as the bottom of the lookup table and this point is defined as P(min). The lookup table address of the stored values of RS are equal to the corresponding TF-(1/2 the interval between TF's). The minimum TF was set as the base offset (OS), above. The lookup table is used to generate the amplitude compensation value (AC).
The program uses the lookup table as follows:
1. Calculate RS
2. Set pointer at P(min)
3. Compare the Actual RS with the value in TF(P)
If Actual RS is less than value in TF(P),
signal is too small, go into fault mode
4. Set pointer at TF(P)
5. Compare the Actual RS with the value in TF(P)
If RS is less than lookup table value at
TF(P) then AC=TF(P)
Add AC to WC (WC=WC+AC); Exit subroutine
If RS is greater than value stored in TF(P)
go ahead to 6
6. See if P is equal to P(max)
If P is equal to P(max), then
AC=TF(P)
Add AC to WC (WC=WC+AC); Exit subroutine
If P is less than P(max), then
Increment pointer P
Go back to #4, above
Having compensated for all of the above, the count is now as accurate as possible for a single dial.
Inter-Dial Compensation
If the position of a single dial pointer were infinitely accurate, and it could be reliably resolved with the measuring system, there would be no need to have more than one dial on a meter register. The only necessary hand would be the most significant digit, which would be read with the necessary resolution. This is obviously not possible. There is back lash in the gear train, and the encoding technique obviously has limits to its accuracy. It is therefore necessary to actually read all of the hands on a register. Given that there may be inaccuracy in determining the true position of the hand, we must cause each hand to be consistent with the previous (less significant) hand readings. Reference is now made to U.S. Pat. No. 4,214,152 where this problem is discussed and solved according to an earlier technique.
Consider two adjacent dials D 1 and D 2 for which D 1 is the least significant of the two dials and D 2 is the most significant of the two dials. Each of the dials include decimal digits arranged in a circular pattern from 0 to 9. The distance between adjacent digits is then 36 degrees. Assuming each dial could be resolved to 100 parts with an accuracy of ±3 parts, we can read the digits to 0.1±0.3. Now, presume the two dials have just been read with the following values:
D.sub.1 =9.2,
D.sub.2 =4.1.
Is the reading 49 or 39? How does an encoder determine what the right reading is? The correct value for D 2 can be resolved by examining the least significant dial D 1 . Dial D 2 is very close to the transition from "3" to "4". Thus, it can be seen that it should be read as a "3", for dial D 1 is close to, but has not yet passed the transition from 9 to 0, which would cause the next dial to logically transition to the higher digit.
To solve this problem an adjustment factor derived from the reading of the previous dial is added to remove this potential ambiguity. It is important to note that the adjusted reading of the previous dial is used in determining this adjustment factor: thus an adjustment factor determined in reading a previous (less significant) adjacent dial is applied to the reading of a subsequent (more significant) dial. More formally the generation of an interdial correction factor for the more significant adjacent dial is always performed after the generation of the correction factor from the previous dial. The determination of all such correction factors proceeds as follows. The transition of the more significant digit of a digit pair should occur upon the transition of the less significant dial from 9 to 0. The value of the less significant digit contains the correct information to resolve possible ambiguities of the more significant digit. In the following discussion these terms will be used:
Terms relating to desired output format (or number base system):
D=number of digits into which a dial is divided, normally equal to N,
D A =adjusted digit value,
D'=digit value, less significant dial,
D"=digit value read before interdial correction, one level of significance higher than D',
N=total number of digits per dial, and gear ratio between adjacent dials,
R=reference zero,
A=digit adjustment value,
A"=adjustment value determined from less significant dial reading, D', to be applied to D",
A d =adjustment value in digitized levels,
Terms relating to internal reading and correction process prior to output:
d=number of digitized levels into which a dial is resolved,
d', d"=digitized level value for a particular hand or shaft position,
d A ', d A "=adjusted digitized level value,
n=dial number being read.
It is desirable and useful to add (algebraically) an adjustment to the more significant digit to increase the probability of having a correct digit reading and to cause a sharp transition as the less significant digit undergoes a transition to zero. This adjusted value of the more significant digit can be expressed:
D.sub.A "=D"+A" (Eq. 1)
Presume that each digit dial can be resolved into d, digitized levels, and that for initial considerations, d is a large number approaching, for practical purposes, infinity; note that resolution is merely the number of digitized levels, and is not the accuracy of the determination of hand position, although it represents the upper limit of accuracy for a single reading. Digit value, D', is related to the digit levels, d', by the ratio: ##EQU3## It is readily apparent that the maximum mechanical error of the more significant hand is plus or minus one-half digit. Thus, as the least significant digit approaches the transition from (in resolved digitized levels) d'=d to d'=0, or in decades, from 9.9999 to 0.0000) if, at d'=d, the equivalent of one-half digit were subtracted from the more significant digit, and if, as the less significant digit passes the transition, one-half digit were added to the more significant digit, readout would undergo an abrupt transition from one digit to the next higher digit. Obviously, if the maximum error of hand reading is plus or minus one-half digit, then when the least significant digit is at the point farthest from next significant digit transition (i.e., 5 on a decade system), then adding or subtracting one-half digit to or from the next significant digit is apt to cause an error. When D'=1/2N (shaft rotation is 180° from the next significant digit transition), the adjustment, A", should be zero. The optimal adjustment for a decimal system can be written: ##EQU4## This equation has the desired property of having an absolute maximum when D' is O or D, and a minimum when D'=1/2N. Note that A" D is derived from D', the less significant digit and applied to D", the more significant digit. The actual adjustment must be made in terms of resolved or digitized levels and must differentiate between slightly before and slightly after a digit. Equation (3) thus becomes (using equation (1)): ##EQU5## the quantity comprising the correction factor to be added from the previous less significant dial and to be independently determined for the next more significant dial. [Note (1) that (d-1/N) 1/2 is used rather than (d/N) /1/2 because d is not a continuous variable; (2) that strictly speaking Eq. 4 is equivalent to (nd/2-1)1/N which approaches d/2 in the limit as n→∞].
From the foregoing analysis a compensation technique has been developed based on an equation derived for the maximum possible compensation achievable of the n th dial which will provide a binary compensation value utilizing the information from all previous dials. The desired digit reading of the n th dial, D n , shall be called R n , such that: ##EQU6## The terms are defined as: n=Dial number (1=Least significant dial),
C=Maximum permissible counts or states (again, this system uses 2560),
WC n =Number of counts for Dial n (0-2559),
R i =Reading (decimal) for i th dial (integer from 0 to 9)
R n =Reading (decimal) for n th dial (integer from 0 to 9)
R n-1 =Reading (decimal integer) for (n-1) th dial,
INT=Integer value of term which follows, truncate to decimal point.
The equation (above) has three terms:
WC n , the raw counts,
C-1/20, a constant term and, ##EQU7## Each of the terms is multiplied by 10/C. The second, constant term is always the same, so no special program manipulations are required. Note that the "Y" term is generated from the previous less significant dial digits (R i ), thus the Y term generated before this dial (R n ) is already compensated.
The addition of the three factors above is accomplished in a simple sequence. For a decimal based system, the flow chart of FIG. 21 outlines the procedure. For the binary system described herein, the following procedure is used:
1. WC n is shifted left two places; this is the same as multiplying it by 4,
2. To the result is added 128, which is 640/20×4,
3. From this a value Y 1 is subtracted; the result is W,
4. Wrap around is checked:
if W is greater than or equal to 2560, then 2560 is subtracted from it,
if W is less than 0 then 2560 is added to it.
At this point there has been created a variable W for each dial, which variable has a value from 0 to 2559. Steps 2 and 3 above performed the inter-dial compensation (IDC), but in a number based from 0 to 2559 (2560 possible values). It can be seen that WC is selected from the family of values defined by the equation: WC=2560/(2 m ) for integer values of m from 0 to 8. Selection of m is based on the needs of the particular situation. For this application m=2. This number is 12 bits long. Now it must be converted to a decimal value and truncated, after which a new IDC value Y 1 can be generated.
Conversion to BCD
It is now desired to send out the final digit value for the dial in ASCII code. For the numerical values (0-9) this means that the first 4 bits from the binary coded decimal (BCD) of the number. This is simply the binary equivalent of the number in 4 bits (e.g. 0=000; 1=001; 2=0010; 3=0011; 4=0100; etc.). This is then combined with three control bits and a parity bit (P011). P is the parity bit which allows checking on the receiving end for data transmission errors.
It will be recalled that there has been generated a 12-bit value W for the dial reading. This 12-bit value will be truncated to the digit value R n . By virtue of the manipulations which have been performed, the highest 4 bits of the 12-bit value are the BCD value of R n . Since the manipulations have been accomplished in an 8-bit microprocessor, it is an easy matter to drop out the low byte Wl (which is the lowest 8 bits), so that this information is not transmitted.
Returning now to the generation of Y 1 the IDC value the value just generated for the dial digit is used to generate a new Y 1 for the next dial. The following mathematical operation is performed:
Y.sub.1 =((R.sub.n ×256)+Y.sub.1)/10
Now this is done as follows:
1. multiply the existing dial reading, R n , by 256,
2. add the result to the existing Y 1 ,
3. divide the result by 10; this is the new Y 1 , to be used on the next dial digit.
Obviously, the value of Y 1 will depend on the digit values of all previous dials. This provides the maximum possible compensation and is to be desired. It does, however, require that the process start off right for the first digit (representing least significant digit) generated. There is sufficient resolution that, if the accuracy permits, there can be generated from the reading of the least significant dial a 1/10th digit. This is done whether or not the value is in the output message. The least significant dial must also start off with the proper initial value of Y 1 .
Before reading the least significant dial, the value of Y 1 is initialized to 128. Note that in calculating the 2560 count value of dial 1 (the least significant dial) there is first added 128 to the reading, and then subtract the initialized value of Y 1 (128) from it. In other words, it is unaffected. The process is as follows:
1. initialize Y 1 to 128,
2. generate C n ,
3. calculate the 12-bit value (W) in 2560 counts, including the IDC using Y 1 ,
4. save the high byte (W h , R n for dial 1) as W s
5. multiply W l by 10, which is the new 12 bit word, W,
6. take the high byte, W h of the new value of W for the digit value, R n , of 1/10 th of the least significant dial,
7. generate a new value of Y 1 , as above,
8. check a jumper on the microprocessor port to see if the 1/1 dial is to be output;
if this is not to be output then clear the new W h to all zeros,
if this is to be output, then leave the new W h alone,
9. shift W h into the digit output routine in which the upper nibble is fashioned (P011) and attached to form the ouput byte,
10. retrieve W s , redefine it as W h ,
11. generate Y 1 as above,
12. shift W h into the digit output routine in which the upper nibble is fashioned (P011) and attached to form the output byte,
13. proceed to read the remaining dials in the normal fashion.
There has thus been described in detail a preferred embodiment of the present invention. It is obvious that some changes might be made without departing from the scope of the invention which is set forth in the accompanying claims. | A transducer formed of one or more electrode arrays is positioned in confronting relation and parallel to the plane of rotation of one or more rotating members. A plurality of phase modulated, two-phase, square wave drive signals of the same amplitude and frequency are applied to each electrode. The signals are combined at a central node or electrode to form, as a result of the signal, the superposition of the algebraic sum of all drive signal pairs. Samples of the resultant signal taken at the same frequency and of a duration of less than one-half the duration of the drive signal period provide a multi-step, synchronously detected signal. The detected signal is a multi-step approximation to a sine wave, the phase angle thereof relative to a timing point being proportional to the angular position of the rotating member. The amplitudes and phase shifts of the multi-step detected signal are then reduced to a plurality of vectors, from which two orthogonal vectors are produced which may be mathematically reduced to the amplitude and phase angle of the aforesaid sine wave. The phase angle is transformed or converted into a binary representative of the hand position. | 6 |
TECHNICAL FIELD
The present invention relates generally to test apparatuses for telecommunication networks.
BACKGROUND
In the early days of telecommunication systems were relative simple compared to telecommunications today. A central office or telephone exchange was connected via 2-wire connection to telephone terminals. When a person wished to place a telephone call from one telephone terminal to another telephone terminal, a connection was established between the two terminals via the telephone exchange. Only AC signals, i.e. speech signals, were transmitted between the two terminals. A DC power source was connected directly to respective telephone terminals, usually this power source was a battery. The DC source is needed to get the telephones active. Ringing voltage for the bell was transmitted between the subscribers and the Central Office.
Later on the DC power source was moved from the individual telephone terminals to the network, e.g. central office or telephone exchange. A Battery Feeding DC Voltage, (V BAT at app. −48 Volts) was introduced at the 2-wire subscriber line by the exchange, placed at the central office. This new DC voltage at the 2-wire subscriber line replaced the batteries at the subscribers, and introduced new signaling possibilities. The possibilities included automatically on-hook and off-hook detection and automatic dial-pulse detection.
The injection of the DC on the 2-wire subscriber line was done in a way without damaging or corrupting the AC-signals, i.e. the speech signals, and most frequently by using Feeding Coils. Later on, other solutions were introduced, e.g. silicon solutions.
Increase in number of telephone terminals and connections have made the systems more complex as well as requiring more complex methods and apparatuses for testing connections. A DC-Feeding Bridge, also known as a DC-source, and a Holding Circuit, also known as a DC-load, are both suitable tools during transmission validation tests. A Holding Circuit is essentially the opposite of a DC-Feeding Bridge. Validation tests are typical carried out to document that a unit is compliant with a given specification.
A DC-Feeding Bridge is a common name for a circuit which is able to introduce a DC voltage on an analogue subscriber line or circuit without any significant degradation in the AC condition or performance of transmission line properties. For examples of using DC-Feeding Bridge and Holding Circuit during validation tests please refer to ETSI TR 101 953-1-1 section 6.3 and ITU-T G.992.3 section A.4.3.3.1.
A DC-Feeding Bridge which fulfils the guidelines or requirements given in ETSI TR 101 953-1-1 section 5 is not easy to design and realize. As mentioned in ITU-T G.992.3 section A.4.3.3.1, specific part of the report follows here, quote in italics:
The inductors and capacitors included in the set up need to be matched so as not to affect the results. When larger ratios of the impedance of the inductors and capacitors to the 50Ω resistors are used, less matching is required in these devices. Inductor matching is typically easier to achieve if a bifilar winding on a single core is used to create the matched pair. Adequate care should be taken to insure no resonance occurs within the measurement frequency range. This may require the use of two inductors in series (of different size) to meet this requirement when the measurement is broadband. It is also important to ensure that in tests that have DC current flowing, no saturation occurs in the inductors. It should also be noted that some types of capacitors vary in value with applied voltage, in general high quality plastic types should be suitable.
Resonance is more or less inevitable because the traditional implementation of a DC-Feeding Bridge requires two, or often more, inductors in series to achieve satisfactory results concerning impedance and bandwidth, to carry out ADSL2 broadband measurements. ITU-T G.992.3 deals with ADSL2, bandwidth 26 kHz to 1.1 MHz.
The problem increases with ADSL2+, bandwidth 26 kHz to 2.2 MHz, but the problem becomes enormous with the introduction of 6-band VDSL2, bandwidth 26 kHz to 30 MHz, because more inductors are needed.
One solution could be to divide the broadband measurements into two or even more different frequency bands, but both test time and complexity is contemplated to increase dramatically; this is, however, still the most common way to carry out the broadband measurements.
SUMMARY
The present invention provides a test apparatus which avoids resonances when elements are used in series, further it is possible to realize a DC-Feeding Bridge suitable for both POTS, plain old telephone service, and broadband measurements.
Still further the present invention provides a simple and new way of implementing a DC-Feeding Bridge and a Holding Circuit which is suitable for the ETSI/ITU specified test-setup for broadband measurements e.g. during 6 band VDSL2 isolation validation tests—between DSL and POTS.
It is an object of the present invention to provide a test apparatus that at least work in the frequency range of 100 Hz to 30 MHz. The specific frequency area or range may be varied according to specific requirements in various telecommunications standards, such as ITU-T G.992.3 and ETSI TR 101 953-1-1, and succeeding standards.
This object, along with other numerous objects and advantages is achieved with a test apparatus for use with a broadband telecommunication network. The test apparatus according to the present invention comprises an electrical DC power source having a first electrical connection and a second electrical connection.
The test apparatus further comprises a first electrical circuit comprising a first electrical circuit input and a second electrical circuit input and a first electrical circuit output and a second electrical circuit output. The first and second electrical circuit input electrically connected to the first electrical connection of the electrical DC power source and the second electrical connection of the electrical DC power source respectively.
In the apparatus electrical connection is established from the first electrical circuit input to the first electrical circuit output via a first inductor having a first inductance. Further an electrical connection being established from the second electrical circuit input to the second electrical circuit output via a second inductor having a second inductance. Additionally a first impedance is transformer coupled to the first inductor.
The apparatus still further comprises a first test apparatus outlet electrically connected to the first electrical circuit outlet and a second test apparatus outlet electrically connected to the second electrical circuit outlet. The first test apparatus outlet and the second test apparatus outlet adapted for establishing electrical contact to a device to be tested.
Advantageously the circuit produce an advantageous frequency profile that is considerable more smooth compared to previous circuits used for DC holding circuits and DC feeding bridges.
The above mentioned elements may advantageously be assembled in a housing or box. The power source may be included in the housing, alternatively be connected thereto. The power source may include a transformer. In some embodiments the power source may be a DC power source.
A person designing a test apparatus according to the present invention may choose particular component characteristics dependent on the desired use of the apparatus. One specific example of an embodiment will be given in relation to the description of FIG. 8 below.
Advantageously the circuit may comprise shared electrical components, e.g. a common inductor being part of a transformer with three inductors, as will be described in more detail with reference to the appended illustrations.
In some embodiments of the present invention first inductance may be substantially equal to the second inductance. Matching of the inductances may in some embodiments provide advantageous frequency profiles or responses.
In a first embodiment of a circuit of the test apparatus according to present invention the first impedance is transformer coupled to the second inductor. In a second embodiment of a circuit of the test apparatus according to present invention a second impedance is transformer coupled to the second inductor. The first embodiment is contemplated to reduce the number of components in the circuit, but other considerations may require that the second embodiment is preferred.
The inductors mentioned throughout the present specification are construed to encompass both coils and solenoids. Also, the impedance may be constituted by suitable electrical components including a resistor, a variable resistor, a capacitor, an inductor or any combinations thereof. The variable resistors may be constituted by rheostats, potentiometers, presets and the like.
In a particular advantageous embodiment of the present invention the test apparatus may include a second electrical circuit comprising a third electrical circuit input and a fourth electrical circuit input and a third electrical circuit output and a fourth electrical circuit output, the third and fourth electrical circuit input electrically connected to the first electrical circuit output and second electrical circuit output, respectively, electrical connection being established from the third electrical circuit input to the third electrical circuit output via a third inductor having a third inductance, electrical connection being established from the fourth electrical circuit input to the fourth electrical circuit output via a fourth inductor having a fourth inductance, a third impedance being transformer coupled to the third inductor.
It is contemplated that multiple circuits may be used for achieving desired frequency responses or profiles. The circuits may be implemented on interchangeable circuits boards or the like, which may be advantageous in the event that a plurality of circuit boards are available to change the frequency profile or response after the test apparatus has been produced, e.g. if it is desired to change the frequency profile or response during testing. The different circuit boards could then include electrical components having different characteristics. The circuits should have the same type of components, arranged in the same manner, as the first and second circuits mentioned above.
Specific embodiments of the present invention include embodiments where one or more of the inductors are constituted by a coil or a solenoid. The specific choice of element may depend on the actual implementation and intended use.
Embodiments of the present invention provides for the transformer coupling between the first inductor and the first impedance being established using a bifilar arrangement, as a transformer with an air core or an iron core or any combinations thereof. The specific choice of implementation may depend on factors such as component availability, cost, reliability etc.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic illustration of a simple, prior art, old-fashion telephone exchange,
FIG. 2 is a schematic illustration of a second, prior art, telephone exchange,
FIG. 3 is a schematic illustration of a traditional, prior art, implementation of a DC-feeding bridge and a DC-holding circuit,
FIG. 4 is a schematic illustration of a block diagram of a DC-feeding bridge and a DC-holding circuit,
FIG. 5 is a schematic illustration of two circuits,
FIG. 6 is a schematic diagram illustrating magnitude of AC input impedance as a function of frequency,
FIG. 7 is a schematic illustration of non-linear load effect on the frequency response,
FIG. 8 is a schematic illustration of a DC-Feeding bridge,
FIG. 9 is a schematic illustration of magnitude relative to AC input impedance,
FIG. 10 is a schematic illustration of a part of a test apparatus having three circuit modules,
FIG. 11 is a schematic illustration of a module of a circuit having two inductors,
FIG. 12 is a schematic illustration of a module of a circuit having three inductors, and
FIG. 13 is a schematic illustration of a module of a circuit having four inductors.
DETAILED DESCRIPTION
FIG. 1 is a schematic illustration of a simple, old-fashion telephone central or central office 10 , where connection between two telephone terminals 12 , 14 is established.
An exchange unit 16 is provided. The unit 16 may establish contact or a path of communication from one terminal to another. The two terminals may be any two terminals of a plurality of terminals, not shown. Each of the terminals 12 , 14 include a power source in the form of a battery. When a connection is to be established, i.e. a person wishes to place a call from one telephone to a person at another telephone, a signal is sent from the terminal 12 to the exchange 16 so that a new connection may be established to the terminal 14 . Speech signal was transmitted from the telephone terminals as AC signals.
FIG. 2 is a schematic view of a second telephone central or central office 18 . In contrast to the central 10 in FIG. 1 the central 18 includes battery source 20 , 22 . The batteries 20 , 22 are coupled to respective lines 24 , 26 for supplying electrical power to telephone terminals 28 , 30 . A switching part 32 established contact between telephone terminals when a call is placed. The establishment of power supply at the central 18 allowed new signaling possibilities e.g. automatically on hook and off hook detection and automatically dial pulse detection.
The electrical power supplied from the central 18 is supplied as a DC signal, which is introduced to the lines without corrupting or distorting the AC speech signals. The power is supplied via feeding coils as shown in FIG. 2 .
FIG. 3 is a schematic illustration of a traditional, prior art, implementation of DC-Feeding Bridge 34 and DC-Holding Circuit 36 .
As mentioned before, and as shown in FIG. 3 , the traditional implementation of a DC-Feeding Bridge 34 and DC-Holding Circuit 36 are done by transformers 38 , 49 and/or coils 42 , 44 , 46 , 48 , 50 , 52 , 54 , 56 in series. The coil pairs 42 and 44 etc. have to be matched or made as bifilar winding transformers as 38 and 49 . A bifilar winding or bifilar coil is an electromagnetic coil that contains two closely spaced, parallel windings.
FIG. 4 schematically illustrates an example of an implementation of a DC-Feeding Bridge 58 according to the teachings of the present invention and includes three sections 60 , 62 , 64 . Further an example of an implementation of a DC-Holding Circuit 66 according to the teachings of the present invention having three sections 68 , 70 , 72 . Instead of using coils to achieve high AC-impedances, the desired impedances are introduced by using transformer coupled impedance.
It is possible to vary the number of modules in series when implementing a DC-Feeding Bridge or a DC-Holding Circuit depending on the required performance. The number of modules in series may be one or more.
There are at least two ways of implementing each section (see FIG. 4 ), namely by using two separate transformers, such as illustrated by the sections 63 A and 63 B, or one transformer with 3 windings as illustrated by section 60 and 68 .
The section 60 comprises three coils and a resistor mounted in parallel with one coil. The section may be construed as a section having two modules, where the middle coil and the resistor are construed as being part of both modules. The first module in section 60 comprises coil 61 A, coil 61 B and resistor 61 C. The second module comprises coil 61 B, resistor 61 C and coil 61 D. Thereby two transformers are established with the use of three coils and one resistor.
The section 62 comprises two modules 63 A and 63 B, each module 63 A and 63 B comprising two coils forming a transformer and a resistor.
The teachings of the present invention allow a person designing a circuit for a test apparatus to combine one or more of the above mentioned sections to achieve or fulfill a given requirement or specification.
It is up to the person designing the circuit or system to achieve the most suitable choice of component characteristics depending on performance requirements. In relation to FIG. 8 an example of an embodiment is given, along with examples of component values or characteristics.
Depending on desired performance or requirements for a specific section in the DC-Feeding Bridge 58 or the DC-Holding Circuit 66 , bifilar winding for the transformers could be used. Also, regarding the transformers with three windings the two windings carrying the DC-current could be bifilar wound.
Matching of transformers (such as TR 2 and TR 2 ′ in section 62 ) is one possible way to improve performance and/or characteristics.
The three-section DC-Feeding Bridge 58 is connected to a pair of transmission lines 74 and 76 .
A computer simulation of the above discussed circuits has been implemented and the setup and results are shown in FIGS. 5-9 . The simulation is discussed below.
FIG. 5 is a schematic illustration of two circuits 82 and 84 . The circuits in FIG. 5 are used to simulate real circuits. The components in the simulation are ideal meaning that e.g. in order to simulate a real transformer an inductor is placed in parallel with a capacitor etc.
As an illustration of the possible resonances, which often occur when using inductors in series, only winding capacitance related to the inductors are added—otherwise everything is still ideal.
The circuit 82 is used to simulate the AC input impedance of a DC-Feeding Bridge as function of frequency. For the simulation the following component characteristics are used:
Coils 83 A having an inductance of 50 mH,
Coils 83 B having an inductance of 5 mH,
Coils 83 C having an inductance of 200 uH,
Capacitors 83 D having a capacitance of 1.5 nF,
Capacitors 83 E having a capacitance of 100 pF,
Capacitors 83 F having a capacitance of 2 pF.
The above is merely one example of an embodiment and is used as a basis for a simulation, the result of which is shown in FIG. 6 . Components with similar value or characteristics are given the same reference numeral in the figure.
The circuit 84 in the right part of FIG. 5 is used to simulate a frequency response to indicate in a very simply way what could happen with the frequency response when the DC-Feeding Bridge is acting as a non-linear load.
The circuit 82 and the circuit 84 both comprise coils of three different values, namely 50 mH, 5 mH and 200 uH. The coils are paired so that two adjoining coils have the same characteristics. The capacitors are paired in the same manner. The capacitors have the values 1.5 nF, 100 pF and 2 pF.
The magnitude of the impedance as function of the frequency is shown in FIG. 6 . The impedance of the simulated DC-Feeding Bridge is significant related to the AC-impedance level used in xDSL broadband systems. The used xDSL AC-impedance level is app. 100 ohm.
At two different frequency intervals in the used broadband bandwidth the impedance is quite below the recommended minimum level at 5000 j ohm and also below 1000 ohm (10 times used AC-impedance level) which may be a satisfactory level for some xDSL measurements.
FIG. 6 is a schematic diagram illustrating the magnitude of the AC input impedance calculated as a function of frequency. FIG. 6 is related to the circuits in FIG. 5 . The y-axis is measured in ohm.
A schematic view at how the non-linear load affect on the frequency response is given in FIG. 7 .
FIG. 7 is a schematic diagram illustrating the amplitude frequency response. FIG. 7 is related to the circuits in FIG. 5 . The y-axis is measured in dB. As may be seen from FIG. 7 the frequency response includes to minima, which is undesirable as it at least makes testing at those frequencies difficult.
From the above is may be appreciated that one advantage of the circuit and test apparatus according to the teachings of the present invention is that it is possible to realize relative simple broadband (100 Hz to 30 MHz) DC-Feeding Bridge and DC-Holding Circuit without undesirable resonances. The term “relative simple” covers both design (calculation and simulation) and realizing (prototyping), but also that it is feasible to implement a broadband DC-Feeding Bridge and DC-Holding Circuit. Circuit designs are exemplified by the schematic illustration shown in FIG. 4
During validation test and production test, a broadband DC-Feeding Bridge and DC-Holding Circuit is contemplated to provide at least the following advantages: Make it possible to carry out and validate each xDSL frequency band sweep requirements in one measurement. By this number of tests decrease dramatically and test time is contemplated to be significantly reduced. Further handling test reports and review of test reports is contemplated to be more simple and manageable. Still further the probability of making mistakes during measurements decreases, i.e. the quality of the test increases.
Other advantages include a simpler test setup i.e. only one DC-Feeding Bridge and DC-Holding Circuit used for both POTS and broadband measurements and a much simpler test system for automatic test and test may be performed on all DSL types using the test system according to the teachings of the present invention.
Overall the apparatus and circuit according to the present invention is contemplated to provide less time used during validation test of e.g. a VDSL2 splitter and cheaper test systems for validation tests and production tests.
FIG. 8 schematically illustrates a DC-Feeding Bridge 86 realized by use of coils. The circuit in FIG. 8 is used to simulate a real circuit. The components in the simulation are ideal meaning that in order to simulate a real transformer an inductor is placed in parallel with a capacitor. The bridge 86 is an alternative implementation of the circuit 82 shown in the left part of FIG. 5 and is realized according to the teachings of the present invention by using transformer coupled impedances.
The example shown in FIG. 8 of a bridge 86 is implemented using the following components:
Coil 88 having an inductance of 50 mH.
Coil 90 having an inductance of 5 mH.
Coil 92 having an inductance of 200 uH.
Capacitor 94 having a capacitance of 1.5 nF.
Capacitor 96 having a capacitance of 100 pF.
Capacitor 98 having a capacitance of 2 pF.
Resistor 100 having a variable resistance, but is fixed at 1.5 kΩ for the calculation of the simulations shown in FIG. 9 .
A DC power source 102 providing a voltage of 48 Vdc.
A resistor 104 having a resistance of 500 ohm.
A capacitor 106 having a capacitance of 100 uF.
Components with similar value or characteristics are given the same reference numeral in the figure. The bridge 86 is further used as a basis for the simulation result shown in FIG. 9 . FIG. 9 is a schematic illustration showing the magnitude of the AC input impedance and relate to the diagram shown in FIG. 8 . Compared to the magnitude of the AC input impedance shown in FIG. 6 the AC input impedance in FIG. 9 is more smooth, and do not include sharp minima, dips or sharp transitions.
The magnitude of the impedance for the DC-Feeding Bridge 86 realized by using transformer coupled impedances is illustrated in FIG. 9 . Compared with the result for the coil solution in FIG. 6 the resonances are damped off.
FIG. 10 is a schematic illustration of a part of a test apparatus having three circuits 110 , 112 , 114 . Each of the circuits includes two inputs 116 and 118 and two outputs 120 and 122 . The circuits 110 , 112 and 114 are connected in series, meaning that the output of one circuit is connected to the input of the next circuit. A power source 124 is connected to the inputs of the first circuit 110 .
FIG. 11 schematically illustrates a circuit 126 . Electrical connection is established between the first input connector 130 to the first output connector 132 via a first inductor 128 . Further an electrical connection is established between the second input connector 136 to the second output connector 138 via a second inductor 134 .
FIG. 12 schematically illustrates a second circuit 140 having three inductors 142 , 144 , 146 . Electrical connection is established between the first input connector 148 to the first output connector 150 via the first inductor 142 . Further an electrical connection is established between the second input connector 152 to the second output connector 154 via a second inductor 144 . An impedance 156 is transformer coupled to the first inductor 142 via the third inductor 146 and the impedance 156 is also transformer coupled to the second inductor 144 .
A test apparatus may according to the present invention comprise a single circuit such as the circuit 140 . In other embodiments the test apparatus may comprise multiple circuits.
FIG. 13 schematically illustrates a third circuit 158 having four inductors 160 , 161 , 164 and 166 . Electrical connection is established between the first input connector 168 to the first output connector 170 via the first inductor 162 . Further an electrical connection is established between the second input connector 172 to the second output connector 174 via a second inductor 164 . A first impedance 176 is transformer coupled to the first inductor 162 via the third inductor 160 . A second impedance 178 is transformer coupled to the second inductor 164 via the fourth inductor 178 .
A test apparatus may according to the present invention comprise a single circuit such as the circuit 158 . In other embodiments the test apparatus may comprise multiple circuits. Advantageous embodiments of the present invention may comprise multiple circuits and may include a mix of circuit types, such as illustrated in FIG. 4 .
The elements labeled as first, second etc. is to be considered as examples. The present invention may encompass embodiments where a number of modules or circuits, such as the examples shown in FIGS. 11-13 , are assembled. Therefore, the mentioning of the first circuit input 130 may as well be a third, fifth or even higher numbered input. The same observations also apply to the remaining elements. | A test apparatus for a broadband telecommunication network. The apparatus includes a DC power source having a first electrical terminal and a second electrical terminal and a DC feeding bridge having a pair of inputs coupled to the first and second electrical terminals of the DC power source. The first electrical circuit having at least one circuit section having a transformer-coupled impedance formed by at least one transformer connected in parallel to a first impedance, and a pair of outputs that are adapted for establishing electrical contact with a device under test (DUT) configured to be disposed on a pair of transmission lines of the broadband telecommunication network. | 7 |
[0001] The present application is a continuation and improvement of Canadian patent application No. 2,859,258 filed Aug. 11, 2014.
[0002] This invention relates generally to aircraft and watercraft propulsion, more particularly to an apparatus and method for generating fluid-dynamic forces, for augmenting propulsion, creating moments providing directional control to said craft, generating increased thrust at reduced speed, ensuring reduced drag at increased speed.
BACKGROUND
[0003] There are a lot of devices that enhance lift generated by a wing at reduced speed, as slats, slots, flaps, but generally they do not provide any lift at zero aircraft speed. There are also well known vertical or short take off and landing (V/STOL) craft that adopts several methods for generating lift during VTOL operation, but each of them has certain disadvantages.
[0004] The most known hovering craft is the helicopter; to create lift it employs a rotor, that in order to achieve high efficiency in hover mode, it has a low disc loading, invariably leading to a large rotor, creating difficulties as the helicopter speed increases, such as retreating blade stall, high drag and loss of efficiency, making the helicopters unsuitable to operate at higher speed. A method to combat these deficiencies are employed by tilted rotor and tilted wing aircraft, such as Bell Boeing V-22 Osprey and Canadair CL-84. Their design is a compromise between hovering configuration efficiency, having higher disk loading than helicopters, and horizontal configuration efficiency, having more propeller disk that they need for generating forward thrust, resulting in more drag, compared to fixed wing aircraft. Another approach to eliminate retreating blade stall and to increase speed of a helicopter is employed by the compound helicopter, such as Piasecki X-49 and Eurocopter X3. This approach involves unloading the rotor disk at high speed, lift being provided partially by small wings, and having forward thrust provided by an auxiliary propulsion system. Although this method increases maximum speed of the compound helicopter, efficiencies, both in hovering and in forward flight, are reduced, because in each mode, there is an extra system, contributing little to the operation, leading to increased weight and drag.
[0005] Static lift generated by a propeller or fan is increased, if the propeller is enclosed into a shroud or a duct, tip losses are reduced, the shroud intake provides itself thrust, but although a shrouded propeller creates more static thrust, the drag created by the shroud becomes prohibitive as speed increases, and above a certain breakeven speed, the efficiency drops below of that provided by an open air propeller. A shroud optimized for high static thrust have a large bell shaped inlet, creating increased amount of drag, inherently inefficient at increased speed. An VTOL craft employing shrouded propellers to achieve VTOL flight is the experimental Bell X-22, but unable to achieve it's goal, the required maximum speed. Aircraft having shrouds optimized for high static trust are the Hiller VZ-1 Pawnee and the SoloTrek XFV. They were designed to operate exclusively in hover mode, inherently having a reduced transport efficiency.
[0006] Channel (Custer) wing type aircraft, as the CCW-5, have wings able to create lift at reduced speed, some test have shown they create an amount of lift even at zero speed. NACA tests of a channel winged aircraft shows less than 10% total thrust increase and lack of control at slow speed. It also suffers from vibration problems because the propeller blades have different loading in the proximity of the channel versus the open air.
[0007] In marine application, there are also devices augmenting propulsion system, but each of them are having certain disadvantages. Devices for increasing propeller thrust, as Kurt nozzles or accelerating ducts, are functioning optimum in certain conditions and designed speed. Major disadvantages are increased drag and cavitation as boat speed increases, and decreased efficiency. Debris and ice can be jammed between the propeller and the nozzle, and are much more difficult to clear than open propellers. Another type of devices used for augmenting propulsion are the decelerating ducts, used for reducing cavitation and noise, for high speed applications. They have certain disadvantages as well, the biggest disadvantage is efficient operation around a limited speed range, reduced thrust, increased drag and decreased efficiency. Debris and ice can be jammed between the propeller and the nozzle as well, the same as for Kurt nozzles.
[0008] There is a definite need for improvement, a need for a system that augments thrust and provides control at reduced speed, yet ensuring low drag at increased speed.
SUMMARY
[0009] It is an object of one or more aspects of the invention to provide craft directional control and propulsion augmentation arrangement and method which is effective at low and zero speed, and ensure low drag at increased speed.
[0010] It is a further object of one or more aspects of the invention to provide such an arrangement and method specifically for attitude control and thrust augmentation, in order to provide V/STOL operation capability and aircraft manoeuvrability without affecting high speed performance of the aircraft.
[0011] Another object of one or more aspects of the invention is to provide such an arrangement and method specifically for efficiently augmenting thrust, to improve control and acceleration, at slow or zero speed, and improving high speed performance of the craft, used for watercraft and aircraft.
[0012] These objects are accomplished by providing a wing, located in a propulsion system fluid intake region. The relative position between the wing and the propulsion system intake can be varied, determining how the intake fluid stream is perturbed and consequently varying direction and magnitude of a fluid-dynamic force generated by the wing, determining craft moments variation, providing directional control, and augmenting propulsion.
[0013] The wing is having a slanted trailing edge coinciding with a fraction of the propulsion system intake, so the propulsion system intake can be placed at a predetermined angle, designed so to optimize certain parameters.
[0014] The wing and the propulsion system are connected using a joint, allowing adjustment in their relative position. For varying the relative position of the lip wing and the propulsion system, a mechanical linkage or an actuator is employed, controlled manually or by a computerized system, configured to vary the relative position as function of data received from input devices, to control the craft attitude, and control the augmentation of the propulsion system.
[0015] At zero or slow speed, the wing and the propulsion system intake are placed adjacently, the intake fluid stream is accelerated creating a low pressure area, influencing the wing so it generates the fluid-dynamic force augmenting thrust and creating control moments for adjusting craft attitude.
[0016] As speed increases, the wing and the propulsion system position is varied such as the wing and the propulsion system are disturbing less the fluid stream, the wing follows the fluid stream convergence, maintaining such an angle of attack to ensure increased lift per drag ratio, varying the wing's generated fluid-dynamic force and determining changes in control moments for adjusting craft attitude.
[0017] At high speed, the wing and the propulsion system are positioned approximately parallel to the fluid stream, so as to reduce their effect on the drag of the craft. The wing as described is further referred as the lip wing.
[0018] Accordingly several advantages of one or more aspects of the invention are as follows: capability to provide efficiently high thrust, to improve acceleration, to provide increased static thrust for watercraft and aircraft, and to improve hovering efficiency for V/STOL aircraft in vertical flight regime. Other objects and advantages are to also ensure low drag at increased speed, improve transport efficiency, reduce fuel consumption and allow a smaller installed power for the craft. Other objects and advantages are the ability to provide directional and attitude craft control, reducing or eliminating need for dedicated control surfaces, and to augment and control the propulsion system generated thrust.
[0019] Other objects and advantages are: reduced cavitation and noise; the wings can act as a pair of rudders; total drag is comparable to a standard propeller and rudder combination; ability of the system to be adjustable, at slow speed creating more thrust, improving acceleration or pull, at high speed having reduced drag and cavitation; the propeller is protected and prevented to hit bottom or foreign objects; ensured ability to easily clean debris from a fouled propeller.
[0020] Further objects and advantages will become apparent from a consideration of the drawings and ensuing description.
[0000]
Drawings Reference Numerals
10 - lip wing;
10′ - blended wing
11 - propeller;
13 - intake region;
14 - articulation;
14′ - bracket;
15 - fluid stream;
16 - slanted trailing edge;
17 - inlet;
18 - propeller perimeter;
19 - wing curvature;
20 - shroud;
21 - control angle;
22 - streamlined surface;
23 - control moment;
24 - actuator;
25 - computerized system;
26 - input device;
27 - main pilot control device;
28 - fluid speed sensor;
29 - slant angle;
30 - canopy;
31 - struts;
32 - pivoting direction;
33 - reduced drag position;
34 - main assembly;
35 - conventional wing;
36 - control surfaces;
37 - fuselage;
38 - auxiliary propeller;
39 - canard wings;
40 - control slats;
41 - vertical stabilizer;
42 - engine nacelle;
43 - wing-let;
44 - fluid dynamic force;
45 - thrust;
46 - vertical axis;
47 - axial component;
48 - transversal component;
49 - yaw control moment;
50 - stabilizer;
51 - vertical component;
52 - pitch control moment;
53 - roll control moment;
56 - wing hub;
LIST AND DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a perspective view of the lip wing apparatus configured for high thrust operation;
[0022] FIG. 2 is a sectional side view of the lip wing apparatus configured for high thrust operation;
[0023] FIG. 3 is a sectional side view of the lip wing apparatus, low drag configuration;
[0024] FIG. 4 is a perspective view of a system having two lip wings, configured for high thrust operation;
[0025] FIG. 5 is a perspective sectional front view of the system having two lip wings;
[0026] FIG. 6 is a perspective view of a single lip wing system aircraft configured for V/STOL operation;
[0027] FIG. 7 is a perspective top view of the single lip wing system aircraft configured for horizontal operation;
[0028] FIG. 8 is a perspective front view of the single lip wing system aircraft configured for horizontal operation;
[0029] FIG. 9 is a block view of a system for controlling the position of an actuator;
[0030] FIG. 10 is a perspective view of an aircraft, having three lip wings, configured for V/STOL operation;
[0031] FIG. 11 is a perspective top view of the aircraft, having three lip wings, configured for horizontal operation;
[0032] FIG. 12 is a perspective side view of the aircraft, having three lip wings, configured for horizontal operation;
THEORY OF OPERATION
[0033] The phenomenon of fluid-dynamic force generation by a wing placed in the intake stream of a propulsion system, such as a propeller or fan, and the effect of the wing exerted on the propulsion thrust have several views or explanations.
[0034] A particular view regards pressure distribution around the system formed by the propeller and the wing. A propeller producing thrust can be viewed as an infinitely thin disk creating a pressure difference between it's sides. The amount of thrust created is equal to the area of the disk, multiplied by the average pressure difference. At the edge of the disk the fluid passes from the high pressure side to the low pressure side, reducing pressure difference and efficiency. The addition of the wing creates a separation between the high and low pressure areas, impeding some of the fluid passage, increasing the average pressure difference and resulting in more thrust being produced. Some of the pressure difference act on the wing as well, so it is generating a fluid-dynamic force. Modifying the relative position of the wing and the propeller, is determining changes in the direction and magnitude of the generated force, enabling directional and thrust control. The total system thrust is a resultant of vector addition between the already increased propeller thrust and the wing generated force.
[0035] Another view involves Newton's third principle; by accelerating a mass of fluid in one direction, thrust is created in the opposite direction. The amount of generated thrust is equal to fluid mass multiplied by acceleration. Although same thrust magnitude can be produced by a small acceleration of a large mass of air, or a large acceleration of a small mass of air, a small acceleration of a large mass of air is much more efficient, requiring less power, as the kinetic energy transmitted to the air is proportional to the squared speed. Most of the accelerating fluid molecules are in front of the propeller, in the intake region. Because molecules in a fluid are interacting with each other, the acceleration vector also have a side-wise component, more pregnant on molecules situated further from the propeller axis, receiving kinetic energy, but contributing less to the thrust. The molecules situated outside the propeller perimeter are even accelerated forward, diminishing produced thrust. Addition of the wing in the intake region, in certain conditions, impedes side-wise and forward acceleration of some molecules, and forcing more molecules, a larger mass of fluid, to be accelerated in the same general direction, increasing efficiency and contributing to the thrust.
[0036] Another particular view, well-known to the art, extensively used to predict and calculate fluid-dynamic forces generated by wings, is given by the mathematical model of circulation or Kutta-Joukowski theorem: generated wing lift is proportional to wing circulation multiplied by free-stream velocity. Unfortunately the Kutta-Joukowski theorem is ill suited to model the lift generated by an airfoil placed in the intake stream of a propulsion system. As defined, the theorem is valid for uniform stream condition, and needs to be amended to correctly predict the lift generated by a wing subjected to a convergent intake stream of a propulsion system.
DETAILED DESCRIPTION
[0037] A first embodiment is presented in FIG. 1 , FIG. 2 and FIG. 3 . A perspective view of the apparatus for providing craft control and augmenting propulsion, configured for providing high thrust is shown in FIG. 1 . It shows a propeller or fan 11 , mounted inside a shroud or duct 20 creating what is known in the art as a shrouded or ducted propeller or fan. The shroud 20 is having an intake region or region of disturbed aspirated fluid 13 . Awing or an airfoil shaped body 10 is located in the intake region 13 . An engine, not shown, rotates and provides power to the propeller 11 , housed in an engine nacelle 42 . Struts 31 provide support structure to the shroud 20 .
[0038] The shroud 20 is exhibiting an inlet or a leading edge 17 . The wing 10 is having a trailing edge 16 coinciding, matching a fraction of the inlet 17 . The trailing edge 16 is slanted, to allow adjacent placement of the shroud 20 , forming a certain angle. The wing 10 placed adjacently to the inlet 17 , creates a lip or a bell shaped, smooth and aerodynamic streamlined surface 22 , enlarges the surface area, and changes the geometry of the inlet 17 so to accelerate more of the fluid flow. The surface 22 is exposed to low pressure, high speed stream of fluid, the same as the top surface of any regular wing, so it have the same properties. The lip wing 10 exhibits a curvature 19 , to geometrically account for the shape of the slanted trailing edge 16 , to provide a lower front profile for the wing 10 , reducing drag at high speed, and also to form a fore and aft channel, to contain and direct, and to better capture the effect of the fluid stream accelerating towards the inlet 17 . The wing 10 as described, is further referred as the lip wing 10 .
[0039] The shroud 20 , the propeller 11 , struts 31 and engine nacelle 42 are connected together, forming a main assembly 34 . The lip wing 10 and the main assembly 34 are connected using aerodynamically shaped pivoting articulations or joints, 14 , to allow adjustment in their relative position. A mechanism for controlling the rotation of the articulations 14 , such as a mechanical linkage or an actuator, is not shown, such devices are well known to the art. Sectioning plane and viewing direction 2 is also shown.
[0040] FIG. 2 shows a sectional side view of the first embodiment, configured for high thrust. The support struts, engine and engine nacelle are not shown. At the intake region 13 , aspirated by the propeller 11 , a fluid stream or flow 15 enters the shroud 20 . The streamlined surface 22 , created by adjacently placing the slanted trailing edge 16 of the lip wing 10 to the inlet 17 fraction, is visible. The lip wing 10 and shroud 20 chords are forming a slant angle 29 . The wing 10 disturbs the fluid flow 15 and creates a fluid-dynamic force 44 .
[0041] A thrust or propulsive force 45 is generated by the propeller 11 . The fluid-dynamic force 44 is vectorially decomposed into two components, one along the thrust 45 direction, resulting in an axial component or vector 47 , and the other along a transverse direction, resulting in a transversal component or vector 48 . The axial component 47 augments the thrust 45 , the transversal component 48 could in certain conditions to create or augment a control moment 23 .
[0042] An arrow 32 shows the pivoting direction of the shroud 20 to reduce the disturbance of fluid stream 15 by the lip wing 10 , consequently reducing drag.
[0043] FIG. 3 shows a side sectional view of the first embodiment, configured for low drag. The support struts and engine are not represented. The lip wing 10 and the shroud 20 are positioned approximately parallel to the fluid stream 15 , to ensure low drag. Pivoting the shroud 20 in the direction shown by the arrow 32 modifies a control angle 21 and the direction of the thrust 45 , created by the propeller 11 , consequently modifying the control moment 23 .
[0044] Operation
[0045] FIG. 2 shows the system configured for generating high thrust, configuration obtained by controlling the control angle 21 , and pivoting the shroud 20 , and placing the inlet fraction 17 adjacently to the slanted trailing edge 16 of the lip wing 10 . This configuration is highly efficient at slow or zero speed, as the lip wing affects highly the fluid stream 15 acceleration, as explained in the theory of operation.
[0046] As speed increases, beside creating an increased drag force, not shown, it determine a reduction of thrust 45 augmentation, caused by the fluid stream 15 speed increase for which the position of the shroud 20 is no longer adequate. The shroud 20 is pivoted, by controlling the control angle 21 , in the direction shown by the arrow 32 , to maintain an adequate position, correlated to the increased fluid speed, increasing thrust augmentation, and reducing drag.
[0047] As speed is increased further, the shroud 20 is pivoted more, as previously described, until reaching the position depicted in FIG. 3 . In this position the lip wing 10 and the shroud 20 , have less influence on fluid stream 15 , having reduced angles of attack, and are generating reduced drag. By controlling the control angle 21 , and pivoting the shroud 20 , the control moment 23 is modified, capable of providing attitude control to the craft.
[0048] System Design
[0049] During design, an aircraft could be provided with one or more lip wings, either located and sharing the intake of one propulsion system, or located at the intake of separate propulsion systems. Lip wing thrust augmentation experiments are showing 65% thrust increase of a lip wing system versus a similar dimension open propeller, and 20% thrust increase of a lip wing system versus a similar dimension shrouded propeller. Depending on the location of the lip wings, in respect to the centre of gravity, or the craft's centre of dynamic pressure, the generated fluid-dynamic forces could be varied differentially, to create or augment one or more control moments, consequently to control the attitude of the craft. Further details of control dynamics are well known to the art.
[0050] Lip Wing Geometry
[0051] Increasing the chord of the lip wing is effectively increasing it's surface area, and cause it to generate an increased amount of force. Increasing the lip wing's chord is effective up to a point because the leading edge of the wing is subjected less and less to the effect of the intake fluid stream. Aircraft weight, wing loading, induced and skin drag, and other considerations could affect the lip wing dimensioning decision.
[0052] The lip wing trailing edge slant angle determines also the force generated by the lip wing. The slant angle is calculated as function of fluid convergence, fluid speed, fluid density and temperature, propeller dimensions, geometry and power applied, shroud and lip wing dimensions and airfoil geometry. The geometry of the whole assembly is calculated to increase some goal parameters, as efficiency of the craft at cruise speed correlated to hovering efficiency, or lift per drag ratio in a certain speed range. The control angle relationship to fluid speed. The intake fluid stream have a high convergence at slow speed, in other words, the side-wise speed of fluid particles located further from axis is high, converging towards the intake. The lip wing lift per drag ratio, L/D, is dependant on the angle of attack, and has an increased value for a specific angle of attack depending on the airfoil geometry. As the intake stream speed increases, the fluid stream convergence becomes lower, decreasing the angle of attack of the wing and decreasing the L/D of the wing. The control angle is changed, pivoting the wing to follow the fluid stream convergence change, to maintain an adequate angle of attack to ensure increased L/D.
[0053] Description of a System for Augmenting Propulsion and Providing Yaw Control for a Watercraft
[0054] Another particular embodiment is a system for augmenting propulsion and providing yaw control for a watercraft, air-boat, hovercraft or ship. The system can be designed for conventional boats, having water immersed propellers, the working fluid being water, or it can be designed for air-boats and hovercrafts, having air propellers. The system is presented in FIG. 4 and FIG. 5 .
[0055] FIG. 4 presents a perspective view of the system. The system is having two lip wings 10 , located in an intake region 13 of a propeller 11 . The lip wings 10 are having similar parts and properties, as defined in the first embodiment. The system have two vertical pivoting articulations or joints 14 for independently pivoting the lip wings 10 on vertical axis 46 . A bracket or similar support structure 14 ′ provide rigidity and support for connected elements. The powering method of the propeller 11 , as an engine or a shaft, is not shown. Also not shown are mechanisms for controlling the rotation of the articulations 14 , such as mechanical linkages or actuators, those devices are well known to the art.
[0056] The propeller 11 is having an outside circular perimeter or circumference 18 , delimiting the intake region 13 . Each of the lip wings are having a slanted trailing edge 16 substantially coinciding with a fraction of the perimeter 18 , and consequently having a circular arc shape. Each of the lip wings 10 are exhibiting a curvature 19 , to geometrically account for the circular arc shape of the slanted trailing edge 16 , and consequently forming a fore and aft channel.
[0057] FIG. 5 is a front perspective sectional view of the system presented in FIG. 4 . At slow speed, each of the lip wings 10 are pivoted, using articulation 14 , and positioned with the slanted trailing edge 16 adjacently to the perimeter 18 of the propeller 11 . Each of the lip wings 10 is disturbing fluid flow and generating fluid-dynamic forces 44 . The propeller 11 is generating a thrust force 45 . Each of the force generated by the lip wings 10 , is vectorially decomposed into two components, one along the thrust 45 direction, resulting in axial components 47 , and another one along a transverse direction, resulting in transversal components 48 . By asymmetrically pivoting the lip wings 10 in respect to propeller 11 , the direction and magnitude of the forces 44 are varied, so the transversal components 48 , having different magnitudes, are creating a yaw control moment 49 . When the speed is increased, the wings are pivoted as indicated by arrows 32 , until reaching a reduced drag position 33 .
[0058] Operation of the System for Augmenting Propulsion and Providing Yaw Control for a Watercraft
[0059] At zero or slow speed, the lip wings are pivoted so their slanted trailing edge 16 is positioned adjacently to the perimeter 18 of the propeller 11 , to enhance the effect of the fluid flow and increase augmentation of the thrust 45 by the fluid-dynamic forces 44 . Pivoting and positioning symmetrically each lip wing 10 , relative to the propeller 11 , determine the transversal components 48 to have the same magnitude, but opposite direction, so they cancel each other. Each of the axial components 47 are adding to the thrust 45 , augmenting it.
[0060] Steering or yaw control is accomplished by pivoting differentially the lip wings 10 in respect to the propeller 11 , differentially modifying transversal components 48 , consequently modifying the yaw control moment 49 .
[0061] As speed increases, the lip wings 10 are pivoted towards a more adequate position, increasing lift per drag ratio, as presented in the first embodiment. Reduced drag is achieved by pivoting the lip wings into positions 33 , as presented in the first embodiment. Yaw control is ensured by using lip wings 10 as rudders, modifying yaw control moment 49 .
[0062] Description of a Single Lip Wing V/STOL Aircraft
[0063] Another particular embodiment is a V/STOL aircraft, presented in FIG. 6 and FIG. 7 . FIG. 6 is showing a perspective view of the aircraft, configured for V/STOL operation.
[0064] The aircraft is having a fuselage 37 , a bow located auxiliary propeller 38 , a stern located lip wing 10 , having same parts and properties as described in the first embodiment. The lip wing is blended with the fuselage 37 , creating a lifting body, and also having a pair of conventional wings 35 , extending the wingspan of the aircraft. The conventional wings 35 are connected to the lip wing 10 , using hubs or hinges or rotary joints 56 , to allow folding for easier storage or road-ability. The conventional wings 35 extremities are ending in wing-let or wing tip devices 43 .
[0065] The aircraft is having, at the stern, a main assembly 34 , similar to the assembly described in the first embodiment, having a shroud 20 , a propeller 11 , struts 31 and an engine nacelle 42 . The main assembly 34 also includes a plurality of control surfaces 36 , rotatable on radial axes, placed in the propeller's 11 slip stream.
[0066] The main assembly 34 is connected to the lip wing 10 , using a pair of articulations 14 . Blended with the fuselage 37 , a vertical stabilizer 41 houses an actuator 24 , for controlling the pivoting of the main assembly 34 .
[0067] The auxiliary propeller 38 is covered top and bottom by a plurality of control slats 40 , exposing the auxiliary propeller 38 , and providing vectored thrust. A pair of canard wings 39 are located on front of the fuselage 37 . A canopy 30 provides visibility and access to a cockpit, not shown.
[0068] FIG. 7 shows a top view, and FIG. 8 shows a front view of the V/STOL aircraft configured for horizontal flight.
[0069] The main assembly 34 is pivoted, using articulations 14 , in a horizontal position, to generate mainly horizontal thrust, for horizontal flight. Visible components, parts of the main assembly 34 , are: the shroud 20 , the engine nacelle 42 , struts 31 , on FIG. 7 are visible control surfaces 36 , and visible on FIG. 8 is the propeller 11 .
[0070] The lip wing 10 is generating lift, as well as the conventional wings 35 , the left conventional wing, partially shown, is symmetrical to the right conventional wing 35 . The hub 56 connects the conventional wings 35 to the lip wing 10 , and during horizontal flight, keeping them in the deployed, extended position. The wing-lets 43 , visible in FIG. 8 , are reducing wing tip loses.
[0071] The control slats 40 are covering the auxiliary propeller, not shown, reducing drag. The canard wings 39 provide lift, and are augmenting pitch and roll control. Visible on the fuselage 37 are also the canopy 30 and in FIG. 7 , the blended vertical stabilizer 41 .
[0072] FIG. 9 shows a system for controlling the position of the actuator 24 , for pivoting the main assembly, not shown, to a control angle, not shown. A computerized system 25 controls the position of the actuator 24 , and is programmed to calculate the control angle, as function of data provided by input devices 26 . A fluid speed sensor 28 provides speed information, a main pilot control device 27 provides pilot control input information. Other input devices as gyro-sensors and accelerometers, are not shown.
[0073] Operation of the Single Lip Wing V/STOL Aircraft
[0074] The aircraft configured for VTOL operation, as shown in FIG. 6 , is generating vertical aerodynamic forces or lift, using the main assembly 34 , the lip wing 10 and the auxiliary propeller 38 . The main assembly 34 is pivoted to a position bringing the shroud 20 adjacently to the lip wing 10 , augmenting thrust, as described in the first embodiment. The pitch control is provided by differentially controlling the propellers 38 and 11 , and by pivoting the main assembly 34 , as described in the first embodiment. Roll and yaw control is provided by control surfaces 36 , placed in the propeller's 11 slip stream, providing control even at slow or zero speed, and the bottom control slats 40 which are vectoring auxiliary propeller thrust.
[0075] As the aircraft speed increases, the conventional wings 35 are starting to provide lift, unloading the main assembly 34 , which can be pivoted, as described in the first embodiment, and increasing horizontal thrust, that could be used to more speed increase.
[0076] Above a certain speed, the canard wings 39 , the lip wing 10 and conventional wings 35 are providing enough lift to balance the weight of the aircraft, the auxiliary propeller 38 is stopped and covered top and bottom by the control slats 40 , and the main assembly 34 is placed in a position as shown in FIG. 7 and FIG. 8 , generating mainly horizontal thrust, position ensuring reduced drag, as described in the first embodiment.
[0077] Pitch and roll control is determined by the canard wings 39 and control surfaces 36 . Yaw control is determined by the control surfaces 36 . Pivoting the main assembly 34 also could contribute to pitch control, as described in the first embodiment.
[0078] Description of a Three Lip Wing V/STOL Aircraft
[0079] Another particular embodiment is a V/STOL aircraft, having a system for augmenting thrust and providing yaw, roll, pitch and thrust control, by using three lip wings arranged around the inlet of a shrouded propeller. The aircraft is presented in FIG. 10 , FIG. 11 and FIG. 12 .
[0080] FIG. 10 shows a perspective view of the aircraft configured for VTOL operation. The aircraft is having an extended wingspan, blended wing 10 ′, a central section of the wing forming a lip wing as described in the first embodiment. At extremities, the blended wing 10 ′ is curved, forming wing tip devices or wing-lets 43 . The aircraft is having another two regular lip wings 10 . All three wings, each of the lip wing 10 and the blended wing 10 ′, are having the same elements, and having the same properties and behaviour as described in the first embodiment. They are independently pivoting on three articulations 14 , are arranged around an inlet 17 of a shroud 20 .
[0081] Each of the lip wing 10 and the blended wing 10 , are pivoted adjacent to the inlet 17 , forming a VTOL or high thrust position. Attached to the shroud 20 are control surfaces 36 , rotatable on radial axes, located in front of a propeller 11 . The control surfaces 36 also act as support elements, and are providing support structure to fuselage 37 , eliminating the need for separate struts, contributing to reduced drag. Each of the lip wing 10 and the blended wing 10 ′ are having stabilizers 50 , housing actuators 24 , for controlling independently the position of each of the lip wing 10 and blended wing 10 ′.
[0082] Each of the lip wing 10 and the blended wing 10 ′ are generating aerodynamic forces, not shown, augmenting and increasing thrust, not shown, provided by the propeller 11 , as described in the first embodiment. The vector addition of wings 10 and 10 ′ generated aerodynamic forces, and the propeller 11 generated thrust, is a resultant force, not shown, that is vectorialy decomposed on an axial component 47 , transversal component 48 , and vertical component 51 . Varying the lip wings 10 , the blended wing 10 ′, and the control surfaces 36 , in different combinations, yaw control moment 49 , pitch control moment 52 , and roll control moment 53 are created.
[0083] FIG. 11 shows a top view, and FIG. 12 shows a side view of the V/STOL aircraft configured for horizontal flight. The lip wings 10 and the blended wing 10 ′ are pivoted, using the articulations 14 , in the horizontal position, approximately parallel to the fuselage 37 , reducing drag. The duct 20 and control surfaces 36 provide attitude control and stability to the aircraft. The wing-lets 43 are reducing the blended wing 10 ′ tip loses and are increasing efficiency. The blended wing 10 ′ is swept forward to increase stability provided by the duct 20 .
[0084] Operation of the Three Lip Wing V/STOL Aircraft
[0085] FIG. 10 is presenting the aircraft configured for high thrust and VTOL operation, the lip wings 10 , and the lip wing section of the blended wing 10 ′, are pivoted adjacently to the inlet 17 of the shroud 20 , increasing the magnitude of the axial component 47 , similar as described in the first embodiment. The force components generated by the lip wings 10 , and the lip wing section of the blended wing 10 ′, along the direction of the transversal component 48 and the vertical component 51 , are cancelling each other.
[0086] By pivoting independently each of the lip wing 10 and blended wing 10 ′, the axial component 47 , transversal component 48 and the vertical component 51 are modified, generating yaw control moments 49 , pitch control moment 52 , roll control moment 53 , and thrust augmentation control. Roll control moment 53 is augmented, and propeller 11 anti-torque moment, not depicted, is generated by differentially pivoting the control surfaces 36 .
[0087] As speed increases, the blended wing 10 ′ outer region, the conventional wing section, is generating lift, and allowing the lip wings 10 and the blended wing 10 ′ to be pivoted, to improve lift per drag ratio, as described in the first embodiment. As speed increases more, the process described can be repeated, until the lip wings 10 and the blended wing 10 ′ are in a horizontal position, approximately parallel to the fuselage, as shown in FIG. 11 and FIG. 12 , ensuring reduced drag.
[0088] Attitude control is provided the same as in VTOL configuration, by pivoting independently each of the lip wing 10 and blended wing 10 ′, by differentially pivoting the control surfaces 36 , determining variation in yaw control moment 49 , pitch control moment 52 and roll control moment 53 .
CONCLUSION, RAMIFICATIONS, AND SCOPE
[0089] It will be apparent to those skilled in the art that the invention is applicable to a wide variety of craft design configurations, providing several advantages as: capability to provide efficiently high thrust, to improve acceleration, to provide increased static thrust for watercraft and aircraft, and to improve hovering efficiency for V/STOL aircraft in vertical flight regime. Other objects and advantages are to ensure low drag at increased speed, improve transport efficiency, reduce fuel consumption and allow a smaller installed power for the craft. Other objects and advantages are the ability to provide directional and attitude craft control, reducing or eliminating need for dedicated control surfaces, and to augment and control the propulsion system generated thrust. Other objects and advantages are: reduced cavitation and noise; the wings can act as a pair of rudders; total drag is comparable to a standard propeller and rudder combination; ability of the system to be adjustable, at slow speed creating more thrust, improving acceleration or pull, at high speed having reduced drag and cavitation; the propeller is protected and prevented to hit bottom or foreign objects; ensured ability to easily clean debris from a fouled propeller.
[0090] While my above description contains many specificities, these should not be construed as limitations on the scope of the invention, but rather as an exemplification of embodiments thereof. Many other variations are possible. For example an aircraft could be designed with two or more apparatus as described in the first embodiment, enhancing thrust and control, and having increased stability. A particular embodiment example could have the wing and the propulsion system connected using a sliding joint. The lip wing could enhance a variety of propulsion systems, as gas turbines, turbofans, turbojets or any other jet engines or propulsion systems designed to create propulsion force by accelerating fluid.
[0091] Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents. | The invention provides a fluid propulsion augmentation arrangement and method, capable of also generating control moments ( 23 ), providing increased thrust ( 45 ) at reduced speed, reduced drag at increased speed, under conditions in which traditional approach cannot provide sufficient performance. It consists of a wing ( 10 ) located in a propulsion system ( 11 ) fluid intake region ( 13 ), having a slanted trailing edge ( 16 ) coinciding with a fraction of the propulsion intake ( 17 ), pivotally connected ( 14 ), allowing position adjustments. At reduced speed, the wing ( 10 ) and the propulsion system intake ( 17 ) are placed adjacently, the intake low pressure determines wing ( 10 ) fluid-dynamic force ( 44 ) generation. Increasing speed, wing ( 10 ) position varies, following fluid stream ( 15 ) convergence change, maintaining an angle of attack for increased L/D, ensuring increased performance, and also varying control moments ( 23 ). | 1 |
CROSS-REFERENCES TO RELATED APPLICATION
[0001] The present invention is a continuation-in-part of patent application Ser. No. 14/042,162 filed on Sep. 30, 2013 and 14/157,302 filed on Jan. 16, 2014.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an aroma diffuser technology and more particularly, to an aroma diffuser using an aroma capsule.
[0004] 2. Description of Related Art
[0005] U.S. Pat. Nos. 8,066,420, 8,262,277 and 8,147,116 disclose an aroma diffuser, which includes a power supply, a heating source, essential oil or aroma wax, and a container for the aroma wax to be contained therein. The essential oil is likely to be leaked from the container as the container is toppled over. After the aroma wax contained in the container is evaporated completely and before a new aroma wax is placed in the container, the user needs to take aroma wax residues out from the container and then to clean the container. During the cleaning process, the user is likely to be stained by the aroma wax residues.
[0006] Further, in U.S. patent application Ser. No. 14/157,302, which was invented and filed by the present inventor, the holder member is a separated member. An external assembly step is necessary to install the holder member, increasing the cost. Further, the holder member is not orthopedically designed for finger installation. It is not convenient for the user to place the aroma capsule in the narrow inside space of the heat conduction container in the aroma diffuser with the fingers, or to take the used aroma capsule out of the aroma diffuser. This disadvantage affects the convenience and efficiency of the use of the aroma capsule in the aroma diffuser.
SUMMARY OF THE INVENTION
[0007] In view of the problems of the prior art, the present invention provides an aroma diffuser using an aroma capsule. The aroma diffuser can be simply and smoothly combined with a disposable aroma capsule. Since the aroma capsule is disposable, a new aroma capsule can replace the used aroma capsule easily.
[0008] Thus, the present invention provides an aroma diffuser using an aroma capsule, which reduces the assembly cost and errors.
[0009] In one embodiment of the present invention, the aroma diffuser using an aroma capsule comprises a hollow housing, a heat conduction device and a heating element. The hollow housing comprises a first opening, a second opening and a holder member. The first opening is located on a top side of the hollow housing. The second opening is located on an opposing bottom side of the hollow housing. The holder member is mounted in the hollow housing, defining therein a holding chamber that faces toward the first opening. The heat conduction device is mounted in the holding chamber and abutted to the bottom hole. The heating element is mounted at a bottom side of the heat conduction device, and kept in contact with the heat conduction device. Thus, the heating element is electrically connected to a power supply unit for generating heat to heat the heat conduction device.
[0010] When using the aroma diffuser using an aroma capsule, the user can place an aroma capsule in the holding chamber of the holder member through the free end of the heat conduction device, and use a power supply unit to provide electricity to the heating element for generating heat to heat the heat conduction device so that the generated heat energy can be transferred through the heat conduction device to the aroma capsule, causing the aroma capsule to release a fragrant vapor toward the outside of the aroma diffuser.
[0011] Unlike the prior art design in which the hollow housing and the holder member are made from different materials and separately mounted, the invention has the hollow housing and the holder member integrally made in one piece without any labor-consuming assembly steps, and thus, the invention saves the component cost of the holder member and enhances the structural stability. During the operation of the heating element to heat the aroma capsule, the heat energy in the holder member and the hollow housing is prohibited from being transferred to the printed circuit board and other electronic components, avoiding thermal damage to the electronic components.
[0012] In one embodiment of the present invention, the holder member further comprises an upper arched wall and a lower upright wall surrounding the holding chamber. The upper arched wall curves inwardly from the top side of the hollow housing. Further, the upper arched wall has a wide top and a narrow bottom. The lower upright wall is extended downwardly from the upper arched wall to the inside of the holder member.
[0013] The aroma diffuser further comprises an aroma capsule placed in the holding chamber of the holder member. The aroma capsule has a bottom side thereof supported on the lower upright wall and kept in contact with the heat conduction device, and an opposing top side thereof suspended in the upper arched wall and defining with the upper arched wall an arched gap therebetween. After the contained aroma in the aroma capsule is used up, the user can insert his or her plump fingers through the arched gap to pick up the used aroma capsule from the holding chamber of the holder member for replacement, and then place a new aroma capsule in the holding chamber inside the holder member of the aroma diffuser quickly. When compared to the prior art design in which the holder member and an attached external member, the holder member and the hollow housing in accordance with the present invention are integrally made in one piece, and thus, the invention greatly the assembly cost and errors. The design of the invention allows the user to replace the aroma capsule conveniently and efficiently.
BRIEF DESCRIPTION OF DRAWINGS
[0014] The invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
[0015] FIG. 1 is an oblique top elevational view of an aroma diffuser having an aroma capsule in accordance with the present invention.
[0016] FIG. 2 is an exploded view of the aroma diffuser having an aroma capsule in accordance with the present invention.
[0017] FIG. 3 is an oblique top elevational view of the hollow housing of the aroma diffuser having an aroma capsule in accordance with the present invention.
[0018] FIG. 4 is a sectional side view of the aroma diffuser having an aroma capsule in accordance with the present invention.
[0019] FIG. 5 is an exploded view of the bottom cover of the aroma diffuser having an aroma capsule in accordance with the present invention.
[0020] FIG. 6 is an oblique bottom elevational view of the aroma diffuser using an aroma capsule in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The following illustrative embodiments are provided to illustrate the disclosure of the present invention, these and other advantages and effects can be apparently understood by those in the art after reading the disclosure of this specification. The present invention can also be performed or applied by other different embodiments. The details of the specification may be on the basis of different points and applications, and numerous modifications and variations can be devised without departing from the spirit of the present invention.
[0022] Refer to FIGS. 1-4 . In an embodiment according to the present invention, an aroma diffuser 1 having an aroma capsule comprises a hollow housing 10 , a heat conduction device 11 , and a heating element 13 . The hollow housing 1 comprises a first opening 101 , a second opening 103 and a holder member 15 . The first opening 101 is defined in a top side of the hollow housing 10 . The second opening 103 is defined in an opposing bottom side of the hollow housing 10 . The holder member 15 is integrally extended from the top side of the hollow housing 10 toward the inside thereof, defining therein a holding chamber 155 that faces toward the first opening 101 . The heat conduction device 11 is mounted in the holding chamber 155 of the holder member 15 . The heating element 13 is disposed on a bottom side of the heat conduction device 11 and kept in contact with the heat conduction device 11 . The heating element 13 is connectible to a power supply unit (now shown) for generating heat energy to heat the heat conduction device 11 of the aroma diffuser 1 .
[0023] In this embodiment, an electrical wire (not shown) is inserted through a bottom hole 153 of the holder member 15 to electrically connect the heating element 13 to the power supply unit.
[0024] Thus, when using the aroma diffuser 1 , the user can put an aroma substance unit through the first opening 101 into the holding chamber 155 of the holder member 15 to keep the aroma substance unit in direct contact with the heat conduction device 11 . The power supply unit provides the necessary working power to the heating element 13 , causing the heating element 13 to generate heat for heating the heat conduction device 11 , enabling the heat energy thus produced to be transferred through the heat conduction device 11 to the aroma substance unit. In this embodiment, the aroma substance unit is an aroma capsule 12 . Thus, the aroma capsule 12 is heated to generate fragrance that is diffused upward through the free end 111 of the heat conduction device 11 .
[0025] Referring also to FIG. 3 and FIG. 4 , in this embodiment, the holder member 15 further comprises an inside flange 19 and a bottom hole 153 . The inside flange 19 extends downwardly inwards from a top side of the holder member 15 . The bottom hole 153 is defined in an opposing bottom side of the holder member 15 and surrounded by the inside flange 19 . The heat conduction device 11 is supported on a top side of the inside flange 19 . The heating element 13 is mounted in the bottom hole 153 , and kept in contact with the heat conduction device 11 .
[0026] Referring to FIGS. 1, 3 and 4 again, in this embodiment, the holder member 15 further comprises an upper arched wall 1510 and a lower upright wall 1512 . The upper arched wall 1510 and the lower upright wall 1512 surround the holding chamber 155 . The upper arched wall 1510 curves inwardly from the top side of the hollow housing 10 , exhibiting a bowl-shaped configuration that is wide at the top and narrow at the bottom. The lower upright wall 1512 extends downwardly from the upper arched wall 1510 to the inside of the holder member 15 . Thus, when placing the aroma capsule 12 in the holding chamber 155 of the holder member 15 , the bottom surface of the aroma capsule 12 is surrounded by the lower upright wall 1512 and kept in contact with the heat conduction device 11 , the opposing top surface of the aroma capsule 12 is surrounded by the upper arched wall 1510 , and an arched gap 1551 is defined between the placed aroma capsule 12 and the upper arched wall 1510 for the insertion of the user's plump fingers to put the aroma capsule 12 in the holder member 15 , or to take the aroma capsule 12 out of the holding chamber 155 of the holder member 15 for replacement. An equivalent holder member of a conventional aroma diffuser is an added external member that does not have the said upper arched wall. The design of the present invention allows the user to smoothly put the aroma capsule 12 in the holder member 15 , or to conveniently take the aroma capsule 12 out of the holder member 15 for replacement.
[0027] In this embodiment, the holder member 15 is formed integral with the hollow housing 10 and inwardly extended from the top side of the hollow housing 10 . Further, the material of the aroma diffuser 1 can be selected from the group of ceramic, metal, wood and plastics. In this embodiment, ceramic is selected for making the aroma diffuser for the advantages of electrical insulation and heat resistance characteristics and aesthetic appearance. In this embodiment, ceramic is used to make the hollow housing 10 and the holder member 15 in one piece. When compared to the conventional design in which the hollow housing and the holder member are independent members made of different materials, the invention has the hollow housing and the holder member be integrally made in one piece without further labor and time-consuming assembly steps, saving component cost and enhancing structural stability.
[0028] Referring to FIG. 5 and FIGS. 2 and 4 again, the heat conduction device 11 further comprises a mounting frame 113 on a bottom side thereof. The mounting frame 113 comprises a screw rod 30 and a bottom cover 16 . The bottom cover 16 is fastened to the second opening 103 of the hollow housing 10 . The heating element 13 is stopped against a bottom surface of the heat conduction device 11 . The screw rod 30 has one end thereof fastened to the bottom cover 16 , and an opposite end thereof inserted through the mounting hole 115 and tightly stopped at the bottom surface of the heating element 13 against the heat conduction device 11 to hold the heating element 13 and the heat conduction device 11 in positive contact with each other, maintaining the stability of heat conduction.
[0029] The heat conduction device 11 is made of a thermally conductive material. Preferably, the heat conduction device 11 is selected from the material group of metal, ceramic and glass. The heat conduction device 11 is configured to adapt the shape of the aroma capsule 12 . The aroma capsule 12 comprises a shell made in the form of a metal film container, and an aroma, such as scented wax or essential oil contained in the shell.
[0030] Further, the heating element 13 can be a metal heating element, ceramic heating element, polymer PTC heating element or composite heating element. In the present preferred embodiment, the heating element 13 is a polymer PTC (positive temperature coefficient) heating element (PTC semiconductor heating element or PTC thermistor).
[0031] Referring to FIGS. 2, 4 and 5 again, in the present preferred embodiment, the aroma diffuser 1 further comprises a DC power socket 17 and a printed circuit board 170 (PCB). The DC power socket 17 and the printed circuit board 170 are electrically coupled together and mounted in the hollow housing 10 . The printed circuit board 170 is electrically coupled with the heating element 13 to provide the heating element 13 with the necessary working power. The bottom cover 16 comprises a mount 160 located at a top side thereof. The DC power socket 17 and the printed circuit board 170 are coupled together and mounted on the mount 160 . The mount 160 comprises a first retaining groove 1601 and a second retaining groove 1602 . The first retaining groove 1601 and the second retaining groove 1602 are symmetrically upwardly extended from a top wall of the bottom cover 16 . The printed circuit board 170 is plugged into the first retaining groove 1601 and the second retaining groove 1602 .
[0032] Referring to FIG. 6 and FIGS. 1, 4 and 5 again, in the present preferred embodiment, the bottom cover 16 further comprises an upright barrel 167 , a flanged lagging sleeve 169 , a washer 162 , a screw nut 164 and an anti-tamper buckle 166 . The upright barrel 167 extends vertically upwardly from a center through hole (not shown) of the bottom cover 16 to a predetermined height. The screw rod 30 has its one end inserted into the upright barrel 167 . The flanged lagging sleeve 169 is made from silicon rubber. In installation, insert the flanged lagging sleeve 169 upwardly into the upright barrel 167 at the center of the bottom cover 16 and sleeve the flanged lagging sleeve 169 onto the screw rod 30 , and then attach the washer 162 onto the screw rod 30 , and then thread the screw nut 164 onto the screw rod 30 to stop the washer 162 against the flanged lagging sleeve 169 , and then fasten the anti-tamper buckle 166 to the screw nut 164 . Thus, the upright barrel 167 and the flanged lagging sleeve 169 prohibit transfer of heat energy from the heating element 13 through the screw rod 30 to the DC power socket and the printed circuit board 170 , avoiding electronic component damage. Further, the anti-tamper buckle 166 comprises two hooks 1621 located at a top edge thereof. The upright barrel 167 comprises two retaining grooves 1671 located on an inside wall thereof. The anti-tamper buckle 166 is attached to the periphery of the screw nut 164 to force the hooks 1621 into engagement with the respective retaining grooves 1671 of the upright barrel 167 to prevent non-professional persons or children from unwillingly dismantling the screw nut, avoiding component damage and dangers.
[0033] Referring to FIGS. 1 and 2 again, the aroma diffuser 1 has an aroma capsule 12 placed therein. The aroma capsule 12 is placed in the holder member 15 . The aroma capsule 12 further comprises a disposable container 121 and an aroma 125 . The disposable container 121 comprises an opening 1211 and a protruding edge 1213 . The protruding edge 1213 extends outward from the opening 1211 . The protruding edge 1213 allows the user to move and operate the aroma capsule 12 easily and conveniently. The aroma 125 is contained in the disposable container 121 . The aroma 125 is, for example, a scented wax, essential oil, flavor block or fragrance stone. In the present preferred embodiment, the aroma 125 is a scented wax.
[0034] Referring to FIG. 1 again, in the present preferred embodiment, the aroma capsule 12 further comprises a breathing film 123 sealed to the opening 1211 of the disposable container 121 to stop the melted scented wax or aroma from flowing out of the aroma capsule, assuring safety.
[0035] Further, the disposable container 121 to be directly manipulated by the user is an aluminum foil shell, thus, there is nothing for the user to worry about breaking the disposable container 121 or washing the disposable container 121 . Further, the user does not need to prepare an extra container for holding the aroma 125 .
[0036] The foregoing descriptions of the detailed embodiments are only illustrated to disclose the features and functions of the present invention and not restrictive of the scope of the present invention. It should be understood to those in the art that all modifications and variations according to the spirit and principle in the disclosure of the present invention should fall within the scope of the appended claims. | An aroma diffuser using an aroma capsule is disclosed to include a hollow housing including a first opening on a top side thereof, a second opening on a bottom side thereof and an integrated holder member downwardly inwardly extended from a top side thereof and defining therein a holding chamber facing toward the first opening, a heat conduction device mounted in the holding chamber, and a heating element mounted at a bottom side of the heat conduction device and kept in contact with the heat conduction device. Thus, an aroma capsule can be placed in the holding chamber and heated by the heating element to release fragrant vapor. After the aroma contained in the aroma capsule is used up, the aroma capsule can be replaced conveniently and rapidly. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns pneumatic pressure pads, or actuators, for cyclically applying pressure forces evenly over an area. The present invention particularly concerns cyclically evenly pressuring an exposed master microfiche film into contact with an unexposed sensitized photographic film at an exposure station of a microfiche duplicator equipment by cyclical application of pressure forces from a reciprocating pneumatic pressure pad.
2. Background of the Invention
Machines for the duplication of film, and particularly microfilm and microfiche, are known. Some such machines are manufactured by Anacomp, Inc.--assignee of the present invention--at its Data Systems Division, and are supported by its Micrographics Engineering Division, P.O. Box 82449 San Diego, Calif. 92138. The duplication machines are commonly used to make multitudinous copies of a single microfilm, or microfiche, master that has typically been generated by, and during, a Computer Output on Microfilm (COM) process. Distribution of the duplicated microfilm or microfiche is an efficient way of disseminating voluminous amounts of information such as, for example, banking transaction records.
The images that appear upon the master, and upon the duplicated, films are typically word and number images. These images are commonly of type fonts, typically as small as 6 points in size, which have been optically reduced at magnification ratios commonly ranging to 96×. These minutely-sized images, and certain still smaller features that result from reducing original images smaller than 6 point type and/or at magnification ratios higher than 96×, demand that the duplication process should be very exacting, and of high quality. Meanwhile, a duplication rate on the order of 2000 copies per hour per duplication machine is typically required if certain large data bases maintained on microfilm or microfiche, such as the data bases generated by large multi-branch banks, are to be replicated each business day by the use of reasonable numbers--on the order of tens--of duplication machines.
The existing duplication machines that perform quality duplication at the required rates typically use the vesicular process: a copy film that has been exposed from a master film is developed by heat alone, and without use of any chemicals or gases. The duplication process is image reversing in that a negative master will produce a positive copy.
One station within a microfilm or microfiche duplication machine is an exposure station. At this station successive unexposed copy films, or successive regions of a roll of unexposed copy film, are exposed, one copy film or copy film region at a time, from a master film. The master film is typically held in a fixture, or jig. It and the copy film must be pressed together into tight uniform contact, and then exposed to a light (or other exposing radiation) source. In order that the fine detail of the image upon the master film should expose without appreciable distortion or blurring onto the copy film, it is necessary that the copy and master films, which are each flexible, should be held together with great uniformity, and without inducing bowing or wrinkling in either film.
This required pressing of a copy film and a master film into close uniform contact at the exposure station of a film, and particularly a microfiche, duplication machine has proven to be troublesome--especially when this pressing has been attempted to be cyclically repetitively accomplished at required high rates, typically faster than one cycle every two seconds. One existing mechanism for realizing the necessary close contact of the master and copy films during an exposure of the copy from the master is based on a moving mechanical stage called an "expose activate assembly". The expose activate assembly consists of (i) a solenoid-operated hook that holds a carriage bearing the copy film to be exposed in an exposure area, which hook is mounted to (ii) a motor-driven eccentric shaft that raises and lowers a platen to force the copy film upon the carriage into pressured contact with a master film that is simultaneously held upon a jig, or fixture. After exposure of the copy film the platen retracts, relieving the contact pressure, and the solenoid is energized so as to raise the hook, and permit the carriage to return to the load position.
The particular part of this particular previous mechanism that is of most relevance to the present invention is its moving platen. It is the planar surface of this platen that is used to press the copy film (as held upon the carriage) and the master film (as held in a jig) into tight contact. Alas, the alignment of the platen, and the results of its movement, are troublesome.
First, the platen must be both horizontally and vertically adjusted, or registered, relative to the master microfiche which is being copied. The horizontal and vertical adjustments determine that the copy film, as held upon the carriage which is moved by the platen, is, as such copy film is brought into pressured contact with the master fiche, of proper position relative to the image that is within the plane of such master microfiche. In order that film should not be wasted, the required registration of the image area of the copy film to the imaged area of the master fiche is typically quite exacting, and on the order of 0.010 inches (0.25 mm). A horizontal adjustment, or registration, of this precision is realized by four detents, each providing a 0.010 inch (0.25 mm) shift in platen position. A vertical adjustment, or registration, of this precision is obtained by two screws that position and align the platen relative to the carriage. Each turn of the vertical adjusting screws normally produces 0.03 inch (0.81 mm) of relative movement.
These adjustments, although sensitive, are not unsatisfactorily troublesome in and of themselves. Unfortunately, in the previous "expose activate assembly" mechanism at least the vertical adjustment within the image plane exhibits an undesirable interplay with a remaining, "z"-axis, adjustment. The "z"-axis, or up-down, adjustment determines that the plane of the copy film as held upon the carriage which is moved by the platen is, as such copy film is brought into pressured contact with the master fiche (held stationary upon a jig), everywhere parallel to the plane of such master fiche. In the previous "expose activate assembly" this adjustment is realized by four adjusting screws, and accompanying lock nuts, that are located at the four corners of the platen. The screws must be adjusted, and locked, so as to both (i) establish proper clearance between the platen and the carriage (holding the copy film), and (ii) establish the plane of the platen to be parallel to the plane of the copy film as held upon the carriage (and also to the plane of the master fiche as held upon the jig). The adjustment of both (i) play and (ii) parallelism is desirably to an accuracy of 0.005 inch (0.10 mm).
All these adjustments are, of course, desirably made and maintained at the indicated tolerances in order to ensure a repetitively reliable and quality duplication of microfiche. They are difficult to so make, and to maintain. In particular, the carriage and the copy film held upon the carriage are reciprocated relative to the frame, and relative to the master film that is fixedly held relative to the frame, not along an axis that is orthogonal to the plane of such master film, but rather along an axis that is skewed relative to this plane. This occurs because the platen is mounted to the duplication machine frame by a "bicycle-chain-type" linkage, and is constrained by this linkage in its movement. The resultant movement of the platen in direction which is not orthogonal to the plane of the mater film causes the previously mentioned interplay between the vertical adjustment(s) and the up-down adjustment(s).
This interplay, as well as the intricacy of the numerous adjustments themselves, make maintenance of the expose activate assembly undesirably labor intensive. Moreover, even such maintenance as is painstakingly and exactingly performed is--innately because of the non-orthogonal movement of the platen and of the copy film borne thereon relative to the master film during their movement together into pressured contact--of uncertain reliability to realize the uniform pressured contact between the two films that is mandated for high-quality duplication.
Another duplication equipment of Anacomp Inc., assignee of the present invention, also pressures a master and a copy film into tight contact at an exposure station while exhibiting fewer problems in so doing. This other equipment relies on a pneumatic bladder, or membrane. The elastomeric bladder is stretched across a rectangular chamber. The films that are to be pressured together are located on one side of the chamber and its bladder. Application of pneumatic pressure within the chamber, and on the opposite side of the bladder to the films, causes the bladder to expand towards the films, pressing the films into contact.
Although this mechanism, and method, is generally more precise and reliable than a mechanism based on moving stages connected by linkages, it also has limitations. The pneumatic bladder is subject to failure, especially where it abrades and stretches against the right-angle corners of the rectangular chamber. Because, upon release of the expansion air pressure, a return of the expanded bladder to its undistended position is based on the bladder's elastomeric properties, cycle speeds are limited. The evenness at which the pressure force may be applied over the area(s) of the workpiece film(s) is limited. Precision in control of the direction at which the pressure force is applied over the area(s) of the workpiece film(s) is limited.
As regards the (i) evenness, and (ii) direction, at which a pressure force is best applied over a prescribed area, it has been found that photographic films are most satisfactorily pressured into uniform, defect-free, even contact if the moving member that contacts such films is not precisely planar, but is very slightly (on the order of a few thousandths of an inch) crowned, or domed. Such a substantially planar crowned member is desirably moved in a direction precisely orthogonal to the plane(s) of the film(s). So moved and contoured, it serves to first, and (very slightly) most tightly, pressure the films together at the center of their image areas. Then the applied pressure force is successively radiated to ever more peripheral regions about this center as the crowned member is brought into ever closer proximity, and into ever stronger pressured contact, with the films.
In summary, it would be desirable to be able to cyclically pressure two flexible planar, film, workpieces into momentary tight physical contact with a high degree of reliability, repeatability, and precision. The film workpieces must be forced, or pressured, together in a manner that preserves the registration of an image area that is to be exposed upon a copy film with a corresponding exposed image area upon a master film. Equally importantly, each of the film workpieces must be forced to lie precisely in a plane without wrinkles, bows, bulges, mounds, creases, or anything else that extends above or below the plane--even minutely and/or over but a small localized region. Finally, the planes of the two film workpieces should be very precisely parallel to each other, and should lie proximate to each other insofar as the physical thickness of the films permit.
SUMMARY OF THE INVENTION
The present invention generally contemplates a pneumatic pressure pad for cyclically producing highly even pressure forces over an area. Moreover, the pressure forces are produced in a controllably even and progressive manner, and in a highly precise direction.
The present invention particularly contemplates use of a pneumatic pressure pad within an exposure stage of a microfiche duplication equipment in order to reliably cyclically progressively evenly directionally pressure a microfiche master film into uniform, even, pressured contact with an unexposed microfiche copy film so that the unexposed copy film may subsequently be exposed from the master film without appreciable distortion.
In its preferred embodiment the pneumatic pressure pad of the present invention is used in a machine of an existing type for duplicating exposed photographic film. Such a duplicator machine has a frame upon which an exposed photographic film is held, a transport mechanism affixed to the frame for moving an unexposed photographic film to a position proximate to the held exposed film, and an light source for exposing the unexposed photographic film from the exposed photographic film. During such exposure the unexposed and exposed films must be held together in pressured contact. This function is realized by a pneumatic pressure pad that cyclically moves in position relative to the frame, and relative to the exposed and unexposed photographic films, in order to cyclically pressure the exposed and unexposed films together into close planar contact during the exposure.
In accordance with the present invention, the pneumatic pressure pad is of a new and improved type. It includes a housing defining a chamber and orifices, a flexible diaphragm dividing the housing's chamber into separate volumes, and a pneumatic source for cyclically applying through one or more orifices of the housing a differential air pressure between the housing's chamber's two volumes, and across the flexible diaphragm. Outside of the housing, a pressure pad presents a substantially planar precision surface in a direction oriented towards a plane of each of the unexposed and exposed films. A shaft connects at one of its ends to the diaphragm for movement therewith. The shaft exits the housing through one of its orifices, and connects at its remaining end to the pressure pad at a location thereon which is oppositely disposed to the pressure pad's precision surface. An optional spring force biases in position the connected pressure pad, shaft, and diaphragm in a direction away from the films.
In operation of the pneumatic pressure pad, a cyclical application of differential air pressure from the pneumatic source causes the diaphragm to expand and to contract, reciprocating the shaft along its axis. The pressure pad that is attached to the shaft accordingly likewise reciprocates relative to the frame, and relative to the exposed and unexposed photographic films. In one, extended, direction of its reciprocating movement, the precision surface of the pressure pad contacts one--normally the unexposed one--of the two films and forces the films together into contact, and against the frame. While the films are held tightly pressed together the unexposed film is exposed from the exposed master film, producing a new negative of the old image that is upon the master film. The pneumatic pressure pad in accordance with the present invention usefully cyclically produces a contact pressure in a very repeatably precise amount, very evenly over the area of contact, in a controllably progressive manner, and in a precise direction. The amount of contact pressure applied is adjustably predeterminable by the amount and pressure of the air that is pneumatically introduced into the housing, and across the diaphragm, during each cycle. These quantities are readily precisely controlled--including by use of a constant capacity pneumatic pressure pump and/or a pressure regulator--and the amount of contact pressure applied is accordingly highly uniform from cycle to cycle.
Probably more importantly, the contact pressure is always applied in a direction that is, and that is maintained to be, very precisely orthogonal to the plane of the films, and of a planar region of the frame against which region the films are held flat. A linear bearing guides the reciprocating movement of the shaft where the shaft passes through the orifice of the housing. This bearing establishes, and maintains, that the operative face of the pad that is affixed to the shaft will move into pressured contact with the films, and with the frame, without inducing any skewing, or bowing, or wrinkling of the film(s) whatsoever.
Finally, the pressure pad is preferably a laminate of (i) a steel plate, and, on the exposed surface, (ii) a plate of elastomeric material. The elastomeric face of the pressure pad preferably presents a very slight crown. Although it is previously known to crown the face of a pressure pad that is used to hold films in pressured contact during contact duplicating, such a crown was previously machined into the elastomer--an expensive and imprecise process. In accordance with the present invention the crown is instead machined into the metal backing plate. A pad of even-thickness elastomeric material is then mounted to the backing plate, and will exhibit a very uniform, durable and precise crown.
When the crowned elastomeric face of the preferred pressure pad is moved into pressured contact with the films it serves to press, and to hold, the films together, and against the frame, in a manner that, if not precisely even in pressure forces applied over the area of contact (being slightly greater at the center of the crown), serves to very smoothly, and gradually, pressure one film in contact with the other. This smoothly progressive contact permits, for example, that features considerably smaller than are presented by six point type reduced in size by 96× may reliably be duplicated over a microfiche exposure area of typically four (4) inches by six (6) inches without incurring any distortion due to imperfect film contact over the contact area. When it is considered that this contact area is cyclically established, and reestablished, at a typical rate of two (2) exposures per second, then the excellent reproduceability of contact forces, and force directions, that is accorded by the apparatus and method of present invention may be appreciated.
These and other aspects and attributes of the present invention will become increasingly clear upon reference to the following drawings and accompanying specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart of the stations and functions of an equipment for duplicating photographic film, particularly microfiche; including an exposure station and an exposure function that is supported by a pneumatic pressure pad in accordance with the present invention.
FIG. 2 is a diagrammatic representation of the same equipment for duplicating photographic film, particularly microfiche, that was previously flow charted in FIG. 1, including the exposure station and exposure function that is supported by a pneumatic pressure pad in accordance with the present invention.
FIG. 3 is an exploded perspective view of a preferred embodiment of a pneumatic pressure pad in accordance with the present invention.
FIG. 4 is a cross sectional detail plan view of a preferred embodiment of a backing plate used in the pneumatic pressure pad in accordance with the present invention previously seen in FIG. 3.
FIG. 5 is a schematic diagram of the pneumatic actuation of the pneumatic pressure pad in accordance with the present invention previously seen in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is embodied in a pneumatic pressure pad assembly, and in a film duplicating machine within which such pneumatic pressure pad assembly may advantageously be used.
A flow chart of the stations and processes of a particular film duplicating machine in which the pneumatic pressure pad assembly in accordance with the present invention is suitably usable is shown in FIG. 1. A diagrammatic representation of the same film duplicating machine is shown in FIG. 2.
The duplicating machine flow charted in FIG. 1 and represented in FIG. 2 may particularly be any of the microfiche duplicators types OP2131, OP2133, or OP2134; or any of the Model 2000 Series; each available from the Data Systems Division, or from the Micrographics Engineering Division, of Anacomp Inc. Other types and models of film duplicating equipments, including equipments for the duplication of film(s) other than cut microfiche, operate under equivalent principles, and correspondingly exhibit equivalent structure and function, to those particular machines that are shown in FIGS. 1 and 2. Accordingly, these other machines, and still other machines and applications requiring the precision pressured holding of planar workpieces, also present suitable environments for application(s) of the pneumatic pressure pad in accordance with the present invention.
Referring to FIGS. 1 and 2, an unexposed copy film, normally in the form of an UNEXPOSED COPY FILM SUPPLY ROLL 1 is fed from a reel 2 under control of a dancing arm 3 (shown in FIG. 2) and transported to an EXPOSURE STATION 4. Separately and independently a previously exposed and developed MASTER FILM 5 (shown in FIG. 1)--variously of the ROLL, CUT FICHE, OR JACKET types--is also transported to the EXPOSURE STATION 4. At this EXPOSURE STATION 4 a pneumatic pressure pad 10 (shown in FIG. 2, fully shown in FIG. 3) serves to bring successive areas of the unexposed copy film into tight physical contact, once per each successive area, with the exposed master film, normally a cut microfiche, that serves as the MASTER 6. Typically many successive exposures are made with the exposure lamp 7 (shown in FIG. 2) while one portion only of the MASTER FILM 5, normally one single cut microfiche, temporarily serves as the MASTER 6.
Each EXPOSED COPY FILM 8 is transported to a DEVELOPER STATION 9 where it is developed by application of HEAT 11 (shown in FIG. 1) in a vesicular process. The exposed and developed film passes through a CLEARING station 12 under force of capstan rollers 13 (shown in FIG. 2), and is cut into fiches by a rotary KNIFE 14. The cut film may be routed into an OUTPUT HOPPER OR OPTIONAL COLLATOR 15 (shown in FIG. 1). Additional guidance, cooling, clearing, and/or anti-static stations and/or elements (not shown) may be located where required or desired along the illustrated sequence of processing the workpiece film.
The duplication machine, and the multi-step duplication process, that is set forth in FIGS. 1 and 2 requires that a microfiche MASTER 6 should be temporarily pressured into tight, and uniform, physical contact with an unexposed region of a COPY FILM 1 during the period of the exposure of the COPY FILM 1 by the lamp 7. A pneumatic pressure pad 10 in accordance with the present invention for cyclically repetitively reliably realizing this pressured contact is shown in exploded perspective view in FIG. 3. The workpiece COPY FILM 1, and the MASTER (film) 6, are acted upon by pressure plate 101 and pad 114, and are not shown in FIG. 3.
The purpose of the pneumatic pressure pad 10 is to (i) cyclically evenly apply a pressure force over an area substantially coextensive with its pad 114, particularly by (ii) maintaining the substantially planar pad 114 (as will be more particularly seen in FIG. 4) parallel to a plane of a planar workpiece(s) against which it presses, and (iii) moving the planar pad 114 in a direction orthogonal to its own (major) plane, and orthogonal to the plane(s) of the workpiece(s) against which it presses. Simplistically expressed, the purpose of the pneumatic pressure pad 10 is to press flat against a flat workpiece by act of moving a (substantially) flat surface in a direction orthogonal to the workpiece's flat surface, and evenly into contact therewith.
There are many mechanical and optical means for precisely establishing flat surfaces, for holding flat surfaces in a precisely parallel orientation, and for moving objects having flat surfaces in precisely predetermined directions. Some of these means are directed, as is the present invention, to pressing one flat surface against other flat surfaces. However, many existing means and methods of high precision operate quite slowly--in accordance with the precision involved.
The pneumatic pressure pad 10 in accordance with the present invention shown in FIG. 3 is capable of cycling its operative surface, or pad 114, in position at rates of 0.7 seconds per cycle, and faster. The pneumatic pressure pad 10 meanwhile maintains all pertinent surfaces to be parallel at all times, and particularly during that instant of time where the pad 114 comes into pressured contact with the workpiece (film), at a tolerance of better than 0.005 inches (0.10 mm).
The pneumatic pressure pad 10 of the present invention is thus a mechanism for cyclically exerting a dry (non-hydrostatic) pressure over an area in a manner so that the applied pressure is highly even during, as well as after, its application. This point deserves repeating: the pneumatic pressure pad 10 of the present invention does not simply produce or maintain an even terminal pressure over an area of a workpiece(s), it builds to this terminal pressure very evenly both in time (i.e., the application of pressure is progressive, and normally linearly progressive) and, most importantly, in space (i.e., the pressure builds, or abates, evenly at all points within the area).
Because the pneumatic motive forces, and the alignments, involved in operation of the operation of the pneumatic pressure pad 10 shown in FIG. 3 will prove to be readily comprehensible, it is tempting to work backwards from the solution offered by the present invention, and to find that it need not be difficult to apply pressure forces with the requisite precision. Needless to say, if it was an elementary matter to spatially move, and to evenly apply even pressure to, planar workpieces so insubstantial as two overlapping pieces of film then the mechanical stage or pneumatic pressuring devices of the prior art would not suffer the performance quality, nor the reliability, problems that are discussed in the BACKGROUND OF THE INVENTION section to this specification.
Considering FIG. 3, an air cylinder is created by pressure plate 101 moving under pneumatic force within a cylindrical cavity, or chamber, formed between lower half pressure chamber member 102 and upper pressure chamber member 103. A shaft spacer 104 maintains a minimum clearance between pressure plate 101 and the underside of lower half pressure chamber member 102. A pressure chamber piston shaft 105, threaded at both ends, is screwed at its lower end into the top of metal pressure plate 101. At its other, upper, end the piston shaft 105 connects to flexible diaphragm 107, which is typically made of neoprene rubber. The diaphragm 107 is sandwiched between lower and upper diaphragm support plates 106,108, and is retained to the threaded upper end thread of piston shaft 105 by washer 115 and nut 116. A compression spring 111 acting between the lower half pressure chamber member 102 and a flat washer 110 at the underside of diaphragm 107 force biases the diaphragm 107, and the piston shaft 105 to which it is connected, upwards. The upwards excursion of the diaphragm 107, and the piston shaft 105, under the force of spring 111 is limited by the contact of elastomeric piston buffer 109, adhesively mounted in a recess machined into the underside of upper half pressure chamber member 103.
In operation of the pneumatic pressure pad 10-- which is shown in exploded perspective view in FIG. 3--the lower and upper half pressure chamber members 102,103 are sealed together airtight under force of screws 118 and washers 117. The diaphragm 107 has holes at its periphery, as illustrated, that slip certain of the screws 118. The diaphragm 107 serves as an airtight seal between upper and lower regions of the cylindrical chamber that is formed between lower and upper half pressure chamber members 102,103. The diaphragm 107, and the piston shaft 105 to which it is connected, are subject to move under a differential air pressure between the upper and lower regions of the cylindrical chamber. The lower region of the chamber is open to the atmosphere through a vent hole, and through tolerances surrounding the shaft 105. Airflow into, and out of, the upper portion of the chamber is through solenoid valve assembly 123 and nipple 119. The nipple 119 is threaded into both solenoid valve assembly 123, and a bore within the upper half pressure chamber member 103, and is secured with Teflon® pipe tape (registered trademark of E. I. DuPont de Nemours & Co., Wilmington, Del., U.S.A.).
The solenoid valve assembly 123 is supplied at its inlet fitting 121, which is also secured by pipe tape, with pressured air from an air compressor (not shown in FIG. 3, shown in FIG. 5) via a pressure hose (not shown in FIG. 3, shown in FIG. 5). A regulator (not shown in FIG. 3, shown in FIG. 5) in-line the external pressurized air supply maintains the pressure to solenoid valve assembly 123 at a predetermined constant value, typically 20 pounds per square inch (p.s.i.).
The gating by solenoid valve assembly 123 of pressurized air from its inlet fitting 121 to the chamber above diaphragm 121, or, at other times, from the chamber to the atmosphere through mufflers 122, is under control of electrical signals transmitted through wires 133 and plugjack 134. This electrical control is typically developed in response to an optical sensor (not shown) that monitors the position of a shutter to the light source 7 at exposure station 4 (shown in FIG. 2). It is obviously possible to cyclically control the operation of solenoid valve assembly 123 based on other sensed, or timed, conditions and/or signals.
Continuing in FIG. 3, a reciprocating motion of shaft 105 in response to the movement of diaphragm 107 within the chamber formed between lower and upper half pressure chamber members 102,103 is guided relative to such members 102,103 by the linear bearing 112. The linear bearing 112 is secured in position by retaining rings 113. The linear bearing 112 is of high quality in order to establish, and maintain over many millions of cycles, the precise position of reciprocating shaft 105, and of the pressure pad 114 affixed thereto. The linear bearing 112 is preferably a Super Ball Bushing® (registered trademark of Thomson Industries, Inc.) linear bearing available from Thomson Industries, Inc., Port Washington, N.Y. 11050 U.S.A.
The film anchor 129 is secured to the metal pressure plate 101 by screws 137 and washers 117. It presents a foot 130, secured by adhesive, that sets against the EXPOSED COPY FILM 8 (shown in FIGS. 1 and 2) as such FILM 8 rests on the duplicating machine frame. The film anchor thus holds the film against any unwanted lateral movement along its length as might otherwise result from pulling forces at DEVELOPER STATION 9 (shown in FIGS. 1 and 2), or further in the microfilm duplication machine.
The chamber members 102,103 (and structure affixed thereto such as solenoid valve assembly 123) are positioned relative to the frame of a microfiche duplicating machine (shown in FIGS. 1 and 2) by socket head mounting screws 138 which pass through slotted holes in the chamber members 102,103. Accordingly, the chamber members 102,103 are constantly maintained in a precise positional relationship to the workpiece film(s) (not shown in FIG. 3) by these four screws 138.
Likewise, both the shaft 105 and its affixed pressure pad 114 positionally reciprocate relative to the members 102,103, and to the workpiece film(s) (not shown in FIG. 3), along a precise, and precisely predeterminable and predetermined, path. This path is in adjustably established to be a direction precisely orthogonal to the plane(s) of the workpiece film(s). By the reciprocating movement of the pressure plate 101 and its affixed pressure pad 114 along this path the workpiece films are best uniformly pressured into uniform even contact without such skewing, warping, bowing, wrinkling, or other distortions as occasionally beset films compressed with previous mechanisms.
In addition to the precision of the reciprocating movement of the pneumatic pressure pad 10, it has been found that, similarly to certain previous microfiche duplicators of the assignee of the present invention, that the pressuring of microfiche films into contact can benefit from a slightly crowned surface to the elastomeric pressure pad 114. It is hypothesized that this slight crown--the effectiveness of which is apparently enhanced by the orthogonal movement of the pressure pad 114 relative to the workpiece films--serves to press the films together from starting from an interior region of the ultimate area of pressured contact, and preceding successively progressively outward over this area of contact.
The center point or line of the crown, its offset (if any) relative to the area compressed, and its height are all parameters that are not necessarily obvious, nor even simple of empirical derivation. However, in accordance with the present invention, it has been recognized that the dimensional parameters of the crown, howsoever established and of whatsoever value, cannot be maintained at optimum if the crown of the pressure pad 114 is not absolutely stable, on the order of thousandths of an inch, over many millions of compression cycles. In previous embodiments of the pressure pad 114 its crown was machined into the elastomeric material. This operation was not only difficult and costly, but was occasionally imprecise. Moreover, a selection of an elastomeric compound for the pressure pad 114 from among compounds that could be precision machined, or molded, placed an undue limitation on the choice of materials. The material of the pressure pad 114 must meet criteria other than acceptance of a precision shape, such as the criteria of durability from wear, insensitivity to temperature and/or environmental gases and contaminants, and long-term retention of elastomeric properties.
In accordance with the present invention, the precision in the creation, and maintenance, of a crown to an elastomeric pressure pad 114 formed from any material is promoted by shaping the metal backing plate 101 to the pressure pad 114 instead of the pressure pad itself. A preferred contour for the metal backing plate 101 is shown in FIG. 4. The nominal thickness "X" of the plate 101 is 0.300+0.003-0.000 inches. The centerline crown rises to a maximum height "Y" of 0.030+-0.003 inches above this thickness over the half the typical 4.0 inch total width of the plate 101. The centerline of the crown is accurately positioned within tolerances "Z1" equals 0.25+-0.12 inches, and "Z2" equals 0.13+-0.06 inches.
Equally, or more, important than the dimensions of the crown to backing plate 101 is that, when machined in steel, it imparts a precise, and precisely stable, crown to an adhered elastomeric pad 114 (shown in FIG. 3) of uniform thickness. The crown of the pad 114 is essentially equal to the crown of the plate 101. It is highly dimensionally stable and long-lived. It, along with the motion to which it and the entire pressure pad 101 is subjected, serves to repeatedly and reliably press film workpieces into undistorted pressured contact. When so pressured into contact, a copy film may be exposed from a master film with minimal loss, or distortion, of any images (normally alphanumeric characters) that appear upon the master film during the photographic replication of these images upon the copy film.
A schematic diagram of a pneumatic system suitable for cyclically repetitively actuating the pneumatic pressure pad in accordance with the present invention is shown in FIG. 5. Pressured air from an air compressor (not shown) is routed via a pressure hose 51 to the pneumatic pressure pad 10. This pressure hose 51 is typically flow connected to pressurized air used at other places within the microfilm duplication machine at connection point 54. A regulator 52 in-line the pressurized air supply maintains the pressure to solenoid valve assembly 123 (shown in FIG. 3) at a predetermined constant value, typically 20 pounds per square inch (p.s.i.).
In accordance with the preceding explanation, the several features of the present invention will be recognized to be susceptible of implementation in alternative forms. The pneumatic cylinder could be of a type other than a diaphragm type, such a ram type. The geometries of the surfaces for the pressuring of the copy and master films into contact are highly preferred. However, the dimensions of these surfaces are, to some degree, variable.
In accordance with these and other alterations and adaptations of the present invention, the invention should be interpreted in accordance with the following claims, only, and not solely in accordance with that preferred embodiment within which the invention has been taught. | A pneumatic pressure pad within an exposure stage of a microfiche duplication equipment cyclically reliably evenly progressively pressures a microfiche master film into uniform pressured contact with an unexposed film in order that the unexposed film may be exposed from the master film without appreciable distortion. A housing of the pneumatic pressure pad defines a chamber divided into separate volumes by a flexible diaphragm. A pneumatic source cyclically applies a differential air pressure between the chamber's two volumes and across the flexible diaphragm. Outside of the housing, an elastomeric pressure pad presents a substantially planar precision crowned surface in a direction oriented towards the planes of each of the unexposed and exposed films. A shaft connects the diaphragm to the pressure pad. Pneumatic movement of the diaphragm cycles the pressure pad in a direction orthogonal to the planes of the films, thereby to cyclically pressure the films into contact without inducing bowing, warping, wrinkles, or other distortions in either film. | 6 |
[0001] The present invention relates to azine metal phosphates, compositions containing the same, a process for preparing the same and their use as intumescent metal-containing flame retardants. Typical representatives are (A-H) (+) [MtPO 4 ] (−) .2H 2 O and (Mel-H) (+) [AlP 2 O 7 ] (−) (where A=melamine or guanidine, Mel=melamine and Mt=Mg or Zn).
BACKGROUND AND TECHNICAL OBJECT OF THE INVENTION
[0002] It is known that intumescent materials have a flame-retardant effect by foaming when strongly heated, e.g. in the presence of a fire, to form an insulating layer which does not burn lightly and in this way suppress, inter alia, the dripping of molten, possibly burning material.
[0003] Intumescent metal-containing melamine phosphates are already known from EP 2 183 314 B1. However, these have the disadvantage of a lack of thermal stability. Thus, for example, the aluminum salt [(Mel-H)] 3 (+) [Al(HPO 4 ) 3] (3−) described there gives off one mole of melamine and two moles of water under thermal treatment at 280 to 300° C., forming [(Mel-H)] 2 (+) [AlP 3 O 10 ] (2−) . A similar situation applies to [(Mel-H)] 2 (+) [MgP 2 O 7 ] (2−) . Furthermore, the products described there can be obtained only in a multistage process. These compounds also all have a disadvantageous modulus (melamine/metal ratio) of 3 or 2.
[0004] Amine metal phosphates are likewise known, as described, for example, in Inorg. Chem., 2005, 44, 658-665, and Crystal Growth and Design, 2002, 2(6), 665-673, but owing to their alkylamine content they have an unsatisfactory thermal stability and are therefore not suitable as flame retardants.
[0005] Cyanoguanidine (dicyandiamide) zinc phosphite is described in Inorg. Chem., 2001, 40, 895-899, where the modulus (cyanoguanidine/zinc ratio) is 1. Guanidine zinc phosphates are not to be found in this publication. Aminoguanidine zinc phosphite is described in Intern. J. of Inorg. Mater., 2001, 3, 1033-1038, where the modulus (aminoguanidine/zinc ratio) is 2:3. The synthesis is likewise carried out hydrothermally. Aminoguanidine zinc phosphates are not to be found in this document. A guanidine zinc phosphite is disclosed in JCS Dalton Trans. 2001, 2459-2461, where the modulus (guanidine/zinc ratio) is 2. Guanidine zinc phosphates having a modulus of 1 are not described.
[0006] Guanidine zinc phosphates are also disclosed in Chem. Mater., 1997, 9, 1837-1846. However, these are prepared hydrothermally and additionally require long reaction times. In addition, these phosphates have a modulus (guanidine/zinc ratio) of 0.5, 2 and 3 and are therefore distinctly different from the azine metal phosphates of the invention, which all have a modulus of 1.
[0007] Metal-free intumescent melamine phosphates are likewise known. Thus, a number of processes for preparing melamine polyphosphates have been described, for example in WO 00/02869, EP 1 789 475, WO 97/44377 and EP 0 974 588. However, preparation according to these processes is time-consuming and the processes are associated with a very high energy consumption because of the high reaction temperatures (340 to 400° C.). In addition, urea is used as further additive.
[0008] A melamine polyphosphate-based formulation which is already on the market is described in EP 1 537 173 B1.
[0009] In addition, there are already intumescent flame retardant systems which are based on melamine, e.g. on melamine salts of 3,9-dihydroxy-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5,5]-undecane 3,9-dioxide (MAP) and on melamine salts of bis(1-oxo-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octan-4-ylmethanol) phosphate (melabis).
[0010] Further intumescent systems are described in chapter 6, pages 129-162 “Fire Retardancy of Polymeric Materials”, 2 nd edition (2010), editors: C. Wilkie, A. B. Morgan, CRS Press, FL, USA.
[0011] Flame retardants for polyamides (PA) and thermoplastic polyesters (PET/PBT) are described in detail in chapters 5 and 6, pages 85-119, “Flame Retardants for Plastics and Textiles”, (2009), authors: E. Weil and S. Levchik, Hanser Verlag, Munich.
[0012] However, the flame retardants described in the prior art have the disadvantage that they frequently have an unsatisfactory flame retardant effect and are unsuitable, or have only limited suitability, for use in plastics, in particular thermoplastic plastics and elastomers in the electrical and electronics sector. In addition, some phosphorus-containing flame retardants influence the electrical conductivity and can thus, for example, have an adverse effect on the properties of a thermoplastic plastics provided with flame retardants in electrical components.
[0013] Despite the numerous publications known from the prior art, there continues to be a need for flame retardants having optimized properties and improved environmental compatibility.
[0014] It was therefore an object of the present invention to provide more effective flame retardants, in particular ones having improved secondary properties such as reduced acidity (higher pH values) and thereby a lower corrosivity and also lower conductivity, compared to the flame retardants known from the prior art.
[0015] In particular, it was an object of the present invention to provide flame retardants which have a high degree of intrinsic (thermal) stability and give a polymer excellent mechanical properties after incorporation of the flame retardant.
[0016] It is therefore an object of the present invention to provide such flame retardants. These should also be readily obtainable.
DESCRIPTION OF THE INVENTION
Azine Metal Phosphates
[0017] The object has surprisingly been achieved according to the present invention by the provision of azine metal phosphates of the general formula [I],
[0000] [(A-H) (+) [M m+ (PO 4 ) x (3−) (P 2 O 7 ) y (4−) ] (−) .pH 2 O] z [I]
[0000] where (A-H) (+) is selected from among melamine-H of the formula (I), melam-H of the formula (II), guanamine of the formula (III), where R is methyl or phenyl, and (amino)guanidine-H of the formula (IV), where R is hydrogen or amine,
[0000]
[0018] M is a metal or metal oxide selected from among Cu, Mg, Ca, Zn, Mn, Fe, Co, Ni, TiO, ZrO, VO, B, Si, Al, Sb, La, Ti, Zr, Ce, Bi and Sn,
[0019] m=2 or 3,
[0020] x and y are each, independently of one another, 0 or 1,
[0021] p is an integer from 0 to 4 and
[0022] z is an integer >5,
[0023] where 1+m=3x+4y.
[0024] These compounds are preferably prepared by a non-hydrothermal route and have a modulus (azine/metal ratio) of 1.
[0025] The azine metal phosphates of the present invention are typically (coordination) polymers and can, as shown by the example of melamine zinc phosphate and melamine aluminum phosphate, be formulated with alternating (phosphate) PO 4 and Zn(OP) 4 tetrahedra or (diphosphate) P 2 O 7 and Al(OP) 4 tetrahedra (structures la and Ib):
[0000]
[0026] Preferred compounds are, for example:
[0027] (A-H) (+) [MtPO 4 ] (−) .pH 2 O, where A is melamine, guanidine or aminoguanidine, Mt is Mg or Zn and p is from 0 to 4;
[0028] (A-H) (+) [AlP 2 O 7 ] (−) , where A is melamine, guanidine or aminoguanidine;
[0029] (A-H) (+) [MtPO 4 ] (−) .pH 2 O, where A is melam, acetoguanamine or benzoguanamine, Mt is Mg or Zn and p is from 0 to 4;
[0030] (A-H) (+) [AlP 2 O 7 ] (−) .pH 2 O, where A is melam, acetoguanamine or benzoguanamine and p is from 0 to 4;
[0031] (A-H) (+) [MtPO 4 ] (−) .pH 2 O, where A is melamine, guanidine or aminoguanidine, Mt is Sn, TiO or ZrO and p is from 0 to 4;
[0032] (A-H) (+) [AlP 2 O 7 ] (−) .pH 2 O, where A is melamine, guanidine or aminoguanidine, Mt is Ce, Sb or Bi and p is from 0 to 4.
[0033] It has surprisingly been able to be shown that the azine metal phosphates of the present invention are more thermally stable than conventional compounds used in flame retardants. In addition, they are simple to prepare in a single-stage process. The process for preparing them saves energy and is economical since the separate preparation of metal dihydrogenphosphates is dispensed with. This is advantageous particularly because metal dihydrogenphosphates are in the majority of cases only storage-stable when hot and tend to form a precipitate at room temperature after a certain time. However, these precipitates can be resolubilized only with difficulty.
[0034] Compositions Containing Azine Metal Phosphate
[0035] Furthermore, it has unexpectedly been found that the effect profile of the azine metal phosphates in respect of flame retardant effect and intumescence behavior can be optimized further by provision of compositions to which synergists or cocomponents have been added. These further components can be metal-containing or metal-free.
[0036] The present invention thus further provides a composition which comprises the above-described azine metal phosphates (component (i)), a further metal-containing component (ii) different from the component (i) and optionally a metal-free component (iii).
[0037] The additional metal-containing component (ii) can comprise, in particular, metal hydroxide, metal phosphate, metal pyrophosphate, hydrotalcite, hydrocalumite, cationically or anionically modified organoclay, stannate salt or molybdate salt, metal borate or metal phosphinate of the formula (V) or (VI) or metal phosphonate of the formula (VII),
[0000]
[0000] where R 1 and R 2 are each, independently of one another, hydrogen, linear or branched C 1 -C 6 -alkyl or phenyl; Mt 1 is Ca, Mg, Zn or Al, m=2 or 3 and Mt is Ca, Mg, Zn, Al, Sn, Zr, TiO, ZrO, Ce, MoO, W0 2 , VO, Mn, Bi or Sb, D=O or S and n is 2 or 3.
[0038] Hydrotalcite and hydrocalumite have, for example, the composition Mg 6 Al 2 (OH) 16 CO 3 and Ca 4 Al 2 (OH) 12 CO 3 . To a person skilled in the art, organoclays are organophile-modified clay minerals (mainly montmorillonites) based on cation exchange, e.g. triethanol tallow ammonium montmorillonite and triethanol tallow ammonium hectorite, as described in Dr. G. Beyer; Konf. Fire Resistance in Plastics, 2007. Anionic organoclays are organophile-modified hydrotalcites based on anion exchange with alkali metal rosinates, unsaturated and saturated fatty acid salts and also long-chain alkyl-substituted sulfonates and sulfates.
[0039] Metal oxides are preferably diantimony trioxide, diantimony tetroxide, diantimony pentoxide or zinc oxide.
[0040] As metal phosphate, preference is given to metal pyrophosphates. Particular preference is given to aluminum pyrophosphate and zinc pyrophosphate and also zinc triphosphate and aluminum triphosphate and likewise aluminum metaphosphate and zinc metaphosphate and also aluminum orthophosphate and zinc orthophosphate.
[0041] Among cationically or anionically modified organoclays, the hydrotalcites modified with alkylsulfate or fatty acid carboxylate or clay minerals modified with long-chain quaternary ammonium are particularly preferred.
[0042] In the case of metal hydroxides, preference is given to magnesium hydroxide (brucite), aluminum trihydroxide (ATH, gibbsite) or aluminum monohydroxide (boehmite) and also hydromagnesite and hydrozincite. Apart from gibbsite and boehmite, mention may also be made of the other modifications of aluminum hydroxides, namely bayerite, nordstrandite and diaspore.
[0043] Furthermore, preferred molybdate salts or stannate salts are ammonium heptamolybdate, ammonium octamolybdate, zinc stannate or zinc hydroxystannate or mixtures thereof.
[0044] These also act as smoke reducers and therefore have particularly advantageous properties in the flame retardants of the present invention.
[0045] From the class of metal borates, preference is given to alkali metal borates, alkaline earth metal borates or zinc borate. Mention may also be made of aluminum borate, barium borate, calcium borate, magnesium borate, manganese borate, melamine borate, potassium borate, zinc borophosphate or mixtures thereof.
[0046] Metal phosphinates are preferably salts in which Mt 1 is selected from among Ca, Mg, Zn and Al. Preferred metal phosphinates are phenylphosphinate, diethyl(methyl, ethyl)phosphinate, in particular in combination with the abovementioned metals.
[0047] Among hypophosphites, the Mg, Ca, Zn and Al salts are particularly preferred.
[0048] Preferred metal phosphinates (VI) and metal phosphonates (VII) are salts having Mt selected from among Ca, Mg, Zn and Al. Particular preference is given to using a metal phosphinate (VI) which is prepared from 6H-dibenz[c,e][1,2]oxaphosphorin 6-oxide [CAS No.: 35948-25-5) in water without use of alkali metal hydroxide. The use of metal phosphonates (VII) which are obtainable, for example, by thermal cyclization of precursors (VI) is also particularly preferred. Very particular preference is given to zinc or aluminum phosphonates and thiophosphonates (VII). The (thio)phosphonates are preferably prepared from the (thio)phosphonic acids (CAS No.: 36240-31-0 and CAS No.: 62839-09-2). All phosphorus precursors are obtainable as commercial products.
[0049] The metal-free (co)component (component (iii) of the composition of the invention) comprises, in particular, red phosphorus, oligomeric phosphate esters, oligomeric phosphonate esters, cyclic phosphonate esters, thiopyrophosphoric esters, melamine orthophosphate or melamine pyrophosphate, dimelamine phosphate, melam (polyphosphate), melem, ammonium polyphosphate, melamine phenylphosphonate and the monoester salt thereof, as described in WO 2010/063623, melamine benzenephosphinate as described in WO 2010/057851, hydroxyalkylphosphine oxides as described in WO 2009/034023, tetrakishydroxymethylphosphonium salts and phospholane (oxide) or phosphole derivatives and also bisphosphoramidates having piperazine as bridge member or a phosphinate ester, the class of NOR-HALS compounds (nonbasic amino ether hindered amine light stabilizers) and mixtures thereof.
[0050] As further additional components, preference is given to melamine polyphosphate, bismelamine zinc diphosphate, bismelamine magnesium diphosphate or bismelamine aluminum triphosphate.
[0051] Among oligomeric phosphate esters, preference is given to phosphate esters of the formula (VIII) or formula (IX),
[0000]
[0052] where each R is independently hydrogen, C 1 -C 4 -alkyl or hydroxy, n=1 to 3 and o=1 to 10. Particular preference is given to oligomers having R n =H and resorcinol or hydroquinone as constituent of the bridge member and also R n =H and bisphenol A or bisphenol F as constituent of the bridge member.
[0053] Preference is given to oligomeric phosphonate esters of the formula (X),
[0000]
[0000] where R 3 is methyl or phenyl, x=1 to 20, R is in each case independently hydrogen, C 1 -C 4 -alkyl or hydroxy, n=1 to 3 and o is from 1 to 10. Particular preference is given to oligomers having R n =H and resorcinol or hydroquinone as constituent of the bridge member.
[0054] Furthermore, preference is given to cyclic phosphonate esters of the formula (XI):
[0000]
[0000] where R 3 is methyl or phenyl, R is hydrogen or C 1 -C 4 -alkyl and y is 0 or 2. Bis[(5-ethyl-2-methyl-1,3,2-dioxaphosphorinan-5-yl)methyl]methylphosphonate P,P′-dioxide is particularly preferred.
[0055] Preference is also given to thiopyrophosphoric esters of the formula (XII)
[0000]
[0000] where each R 1 and R 2 is independently hydrogen or C 1 -C 4 -alkyl. 2,2′-Oxybis[5,5-dimethyl-1,3,2-dioxaphosphorinan]2,2′-disulfide is particularly preferred.
[0056] Among the hydroxyalkylphosphine oxides, preference is given to isobutylbishydroxy-methylphosphine oxide and its combination with epoxy resins, as described in WO-A 2009/034023.
[0057] Among the tetrakishydroxyalkylphosphonium salts, the tetrakishydroxymethyl-phosphonium salts are particularly preferred.
[0058] Among the phospholane or phosphole derivatives, dihydrophosphole (oxide) derivatives and phospholane (oxide) derivatives and also salts thereof, as described in EP 1 024 166, are particularly preferred.
[0059] Among the bisphosphoramidates, the bis-di-ortho-xylyl esters having piperazine as bridge member are particularly preferred.
[0060] Particular preference is likewise given to phosphinate esters such as benzenemonophenyl ester derivatives or 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (6H-dibenzo(c,e)(1,2)-oxaphosphorin-6-one) derivatives as shown in the following formulae:
[0000]
[0000] X=(CH 2 ) y , where y=2-18.
[0000]
[0000] where R is C 1 -C 4 -alkyl, n is from 1 to 6 and x is from 1 to 3. Particular preference is given to compounds of the formula (XIII), (XIV) or (XV) as shown below.
[0000]
[0000] bis-9,10-Dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (6H-dibenz[c,e][1,2]oxa-phosphorin 6-oxide) compounds (formula XV) and 10-benzyl-9-oxa-10-phosphaphenanthrene 10-oxide, CAS No.: 113504-81-7. The preparation of these compounds is described in Russ. J. Org. Chem. 2004, 40(12), 1831-35. Further 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (6H-dibenz[c,e][1,2]oxaphosphorin 6-oxide) derivatives suitable for the purposes of the present invention are described in U.S. Pat. No. 8,101,678 B2 and U.S. Pat. No. 8,236,881 B2.
[0061] Instead of 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (6H-dibenz[c,e][1,2]oxaphosphorin 6-oxide), it is also possible to use dihydrooxaphosphaanthracene oxid(one). An overview may be found in WO-A 2008/119693.
[0062] Among the NOR-HALS compounds, preference is given to the following compounds:
[0000]
[0000] where R′═CH 3 , n-C 4 H 9 or c-C 6 H 11
[0000]
[0000] where R′═CH 3 , n-C 4 H 9 or c-C 6 H 11
[0000]
[0000] where R′═CH 3 , n-C 4 H 9 or c-C 6 H 11
[0000]
[0000] where R′═CH 3 , n-C 4 H 9 or c-C 6 H 11
[0000]
[0000] where R′═CH 3 , n-C 4 H 9 or c-C 6 H 11
[0063] In addition, polyols, aminouracils, POSS compounds, trishydroxyethyl isocyanurate, melamine cyanurate, expandable graphite or mixtures thereof are likewise preferred. POSS compounds (polyhedral oligomeric silsesquioxanes) and derivatives thereof are described in more detail in POLYMER, vol. 46, pp. 7855-7866. POSS derivatives based on methylsiloxane are particularly preferred here.
[0064] Furthermore, trishydroxyethyl isocyanurate polyterephthalates and triazine polymers having piperazin-1,4-diyl bridge members and morpholin-1-yl end groups can also be present in the flame retardants of the present invention.
[0065] Furthermore, the following additives can be present in the flame retardants of the present invention: bisazine pentaerythritol diphosphate salts, hexaaryloxytriphosphazenes, polyaryloxyphosphazenes and siloxanes, for example of the general formula (R 2 SiO)r or (RSiO 1.5 )r.
[0066] Mixtures of two or more of the above-described compounds can in principle also be present in the compositions of the present invention.
[0067] Particular preference is given to combinations of two such as:
MZP or MAP 2 (melamine zinc phosphate/melamine aluminum diphosphate) and Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 CAS No.: [165597-56-8], Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 CAS No.: [139005-99-5], Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 CAS No.: [145826-41-1] as per formula (VI); Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 CAS No.: [147025-23-8], Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 CAS No.: [69151-14-0], Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 CAS No.: [121166-84-5], Ca (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 CAS No.: [144722-45-2] as per formula (VII);
M 2 ZP 2 or M 2 AP 3 (dimelamine zinc diphosphate/dimelamine aluminum triphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 .
[0083] Very particular preference is given to combinations of three such as:
MZP or MAP 2 (melamine zinc phosphate/melamine aluminum diphosphate) and Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and zinc borate.
M 2 ZP 2 or M 2 AP 3 (dimelamine zinc diphosphate/dimelamine aluminum triphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and zinc borate.
MZP or MAP 2 (melamine zinc phosphate/melamine aluminum diphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and zinc stannate.
M 2 ZP 2 or M 2 AP 3 (dimelamine zinc diphosphate/dimelamine aluminum triphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and zinc stannate.
MZP or MAP 2 (melamine zinc phosphate/melamine aluminum diphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and boehmite.
M 2 ZP 2 or M 2 AP 3 (dimelamine zinc diphosphate/dimelamine aluminum triphosphate) and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 ; and boehmite.
MZP+MPP and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 .
MAP 2 +MPP and
Mg (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 , Al (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 3 , Mg (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 , Zn (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 2 or Al (10-oxy-9,10-dihydro-9-oxaphosphaphenanthrene 10-oxidate) 3 .
[0140] Use of the azine metal phosphate of the invention
[0141] A particular embodiment of the invention provides for the use of the azine metal phosphate of the invention as flame retardant in a polymer or a polymer mixture. The present invention therefore further provides compositions as described above which additionally contain a polymer or a polymer mixture. The above-described composition comprising the components (i), (ii) and optionally (iii) is preferably produced first and this composition is incorporated into the polymer or the polymer mixture.
[0142] The invention also provides a process for producing flame-retarded polymer molding compositions, characterized in that the stabilized flame retardants according to the invention are homogenized with the polymer pellets and possibly additives in the polymer melt at elevated temperatures in a compounding apparatus and the homogenized polymer strand is subsequently taken off, cooled and pelletized. The pellets obtained are, for example, dried at 90° C. in a convection oven.
[0143] The compounding apparatus is preferably from the group consisting of single-screw extruders, multizone screws or twin-screw extruders. Suitable compounding apparatuses are single-screw extruders, e.g. from Berstorff GmbH, Hanover, and/or Leistritz, Nuremberg, multizone screw extruders having three-zone screws and/or short compression screws, co-kneaders, e.g. from Coperion Buss Compounding Systems, CH-Pratteln, e.g. MDK/E46-11 D, and/or laboratory kneaders (MDK 46 from Buss, Switzerland with L=11 D); twin-screw extruders, e.g. from Coperion Werner Pfleiderer GmbH & Co. KG. Stuttgart (ZSK 25, ZSK 30, ZSK 40, ZSK 58, ZSK MEGAcompounder 40, 50, 58, 70, 92, 119, 177, 250, 320, 350, 380) and/or from Berstorff GmbH, Hanover, Leistritz Extrusionstechnik GmbH, Nuremberg; ring extruders, e.g. from 3+Extruder GmbH, Laufen, having a ring of from three to twelve small screws which rotate around a static core and/or planetary gear extruders, e.g. from Entex, Bochum and/or devolatilization extruders and/or cascade extruders and/or Maillefer screws; compounders having contrarotating twin screws, e.g. Complex 37 or 70 types from Krauss-Maffei Berstorff.
[0144] The polymer is typically a thermoplastic which is preferably selected from the group consisting of polyamide, polycarbonate, polyolefin, polystyrene, polyester, polyvinyl chloride, polyvinyl alcohol, ABS and polyurethane, or a thermoset which is preferably selected from the group consisting of epoxy resin (with hardener), phenolic resin and melamine resin.
[0145] It is also possible to use mixtures of two or more polymers, in particular thermoplastics and/or thermosets, in which the azine metal phosphate of the invention is used as flame retardant.
[0146] Examples of such polymers are:
polymers of monoolefins and diolefins, e.g. polypropylene, polyisobutylene, poly-1-butene, poly-4-methyl-1-pentene, polyvinylcyclohexane, polyisoprene or polybutadiene, and polymers of cycloolefins, e.g. of cyclopentene or norbornene and polyethylene (also crosslinked), e.g. high density polyethylene (HDPE) or high molecular weight (HDPE-HMW), high density polyethylene having ultrahigh molecular weight (HDPE-UHMW), medium density polyethylene (MDPE), low density polyethylene (LDPE) and linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE) and also copolymers of ethylene and vinyl acetate (EVA); polystyrenes, poly(p-methylstyrene), poly(a-methylstyrene); copolymers and graft copolymers of polybutadiene-styrene or polybutadiene and (meth)acrylonitrile, e.g. ABS and MBS; halogen-containing polymers such as polychloroprene, polyvinyl chloride (PVC); polyvinylidene chloride (PVDC), copolymers of vinyl chloride-vinylidene chloride, vinyl chloride-vinyl acetate or vinyl chloride-vinyl acetate; poly(meth)acrylates, polymethyl methacrylates (PMMA), polyacrylamide and polyacrylonitrile (PAN); polymers of unsaturated alcohols and amines or acyl derivatives or acetals thereof, e.g. polyvinyl alcohol (PVA), polyvinyl acetates, stearates, benzoates or maleates, polyvinyl butyral, polyallyl phthalates and polyallylmelamines; homopolymers and copolymers of cyclic ethers, e.g. polyalkylene glycols, polyethylene oxides, polypropylene oxides and copolymers thereof with bisglycidyl ethers; polyacetals such as polyoxymethylenes (POM) and also polyurethane and acrylate-modified polyacetals; polyphenylene oxides and sulfides and mixtures thereof with styrene polymers or polyamides; polyamides and copolyamides derived from diamines and dicarboxylic acids and/or from aminocarboxylic acids or the corresponding lactams, e.g. polyamide 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12, 12/12, polyamide 11, polyamide 12, aromatic polyamides derived from m-xylylenediamine and adipic acid and copolyamides modified with EPDM or ABS. Examples of polyamides and copolyamides are derived from ε-caprolactam, adipic acid, sebacic acid, dodecanoic acid, isophthalic acid, terephthalic acid, hexamethylenediamine, tetramethylenediamine, 2-methylpentamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, m-xylylenediamine or bis(3-methyl-4-aminocyclohexyl)methane; polyureas, polyimides, polyamidimides, polyetherimides, polyesterimides, polyhydantoins and polybenzimidazoles; polyesters derived from dicarboxylic acids and dialcohols and/or hydroxycarboxylic acids or the corresponding lactones, e.g. polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, poly-1,4-dimethylcyclohexane terephthalate, polyalkylene naphthalate (PAN) and polyhydroxybenzoates, polylactic esters and polyglycolic esters; polycarbonates and polyester carbonates; polyketones; mixtures or alloys of polymers mentioned above, e.g. PP/EPDM, PA/EPDM or ABS, PVC/EVA, PVC/ABS, PBC/MBS, PC/ABS, PBTP/ABS, PC/AS, PC/PBT, PVC/CPE, PVC/acrylate, POM/thermoplastic PUR, PC/thermoplastic PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA6.6 and copolymers, PA/HDPE, PA/PP, PA/PPO, PBT/PC/ABS or PBT/PET/PC, and TPE-O, TPE-S and TPE-E; thermosets such as PF, MF or UF or mixtures thereof; epoxy resins—thermoplastics and thermosets; phenolic resins; wood-plastic composites (WPC) and polymers based on PLA, PHB and starch.
[0166] The concentration of the flame retardant preparations according to the invention consisting of the azine metal phosphate (component (i)) and the additional metal-containing component (ii) and optionally the metal-free component (iii) in a polymer or a polymer mixture is preferably from 0.1 to 60% by weight, based on the polymer or the polymer mixture. The component ratio of azine metal phosphate (i) to the cocomponents (ii) and optionally (iii) in the composition is preferably in the range from 1:1 to 1:4.
[0167] In a preferred embodiment of the invention, the polymer material of the invention can contain further fillers which are preferably selected from the group consisting of metal hydroxides and/or metal oxides, preferably alkaline earth metal hydroxides, for example magnesium hydroxide, and aluminum hydroxide, silicates, preferably sheet silicates such as bentonite, kaolinite, muscovite, pyrophyllite, marcasite and talc, or other minerals such as wollastonite, silicon dioxide such as quartz, mica, feldspar, and also titanium dioxide, alkaline earth metal silicates and alkali metal silicates, carbonates, preferably calcium carbonate, also talc, clay, mica, diatomaceous earth, calcium sulfate, barium sulfate, pyrite, glass fibers, glass particles, glass beads and glass spheres, wood flour, cellulose powder, carbon black, graphite, chalk and pigments.
[0168] These fillers can give the polymer material further desired properties. In particular, the mechanical stability can be increased by, for example, reinforcement with glass fibers or the polymer can be colored by addition of dyes.
[0169] In a further embodiment, the polymer materials can contain further additives such as antioxidants, light stabilizers, processing aids, nucleating agents, antistatics, lubricants such as calcium stearate and zinc stearate, viscosity improvers, impact modifiers and in particular compatibilizers and dispersants.
[0170] Furthermore, foam formers can be added to the polymer in addition to the azine metal phosphate according to the invention. Foam formers are preferably melamine, melamine-formaldehyde resins, urea derivatives such as urea, thiourea, guanamines, benzoguanamines, acetoguanamine and succinylguanamine, dicyandiamide, guanidine and guanidine sulfamate and also other guanidine salts or allantoins and glycolurils.
[0171] In addition, a polymer containing the azine metal phosphate of the invention can also contain antidripping agents, in particular ones based on polytetrafluoroethylene. The concentration of such antidripping agents is preferably from 0.01 to 15% by weight, based on the polymer to be processed.
[0172] Process for preparing azine metal phosphates according to the invention
[0173] The invention also provides a process for preparing the above-described azine metal phosphates according to the invention by reacting an azine starting material (A) with a metal oxide starting material (B) and orthophosphoric acid (C), wherein the azine starting material (A) is selected from among melamine of the formula (I-H), melam of the formula (II-H), guanamine of the formula (III-H) and guanidine (bi)carbonate of the formula (IV-H) and the metal oxide starting material (B) is selected from among metal oxides, metal hydroxides and/or metal carbonates.
[0000]
[0174] Preferred azine starting materials are melamine, guanamine and melam. Preferred metal oxides are selected from among MgO, ZnO, Al 2 O 3 and SnO, ZrO 2 , preferred metal hydroxides are selected from among Mg(OH) 2 , Zn(OH) 2 , Al(OH) 3 , Ce(OH) 3 and Bi(OH) 3 and (basic) metal carbonates are preferably selected from among CaCO 3 , MgCO 3 , basic magnesium carbonate (hydromagnesite), basic zinc carbonate and basic zirconium carbonate. Particular preference is given to Mg(OH) 2 , ZnO, Al(OH) 3 and basic zinc carbonate. In principle, mixtures of two or more of the abovementioned compounds can also be used as azine starting material (A) and/or as metal oxide starting material (B).
[0175] The process usually comprises the following steps:
[0176] (a) initial charging of an aqueous suspension of azine component (A) and metal oxide starting material (B) (i.e. metal (hydr)oxide or (basic) metal carbonate),
[0177] (b) addition of orthophosphoric acid,
[0178] (c) heating to preferably 60-80° C.,
[0179] (d) isolation of the product and
[0180] (e) optionally drying to constant weight and/or tempering at typically 250-300° C.
[0181] The process preferably comprises reaction of the components (A-1 to A-4):(B):(C) in a molar ratio of (1 to 3):(1):(1 to 3), as a result of which it is, in particular, ensured that additional melamine phosphates or (amino)guanidine phosphates are formed in-situ.
[0182] Step (a) can particularly preferably be followed by a granulation process. This can preferably be carried out as spray agglomeration in a spray dryer, spray granulator (top spray or bottom spray, countercurrent process), fluidized-bed granulator or in a paddle mixer or horizontal dryer, with the water introduced being removed until the desired residual moisture content is obtained. The granulation can take place by spray drying of an aqueous suspension of an azine metal phosphate of the formula (I) at usually 70-80° C. or alternatively as spray granulation starting out from a feed mixture of components (A) and (B) as fluidized bed and spraying of component (C) onto the fluidized bed and subsequent drying. The fluidized bed temperature is kept constant in the range from 70-80° C., with the granules drying at the same time and a free-flowing, non-dusting granular material being formed. The residual water content is about 0.5-1%.
[0183] Tempering of the reaction product typically takes place at from 220 to 350° C., preferably from 250 to 300° C.
EXAMPLES
[0184] The following examples serve to illustrate the invention, with the compounds of examples 1 to 6 describing the process of the invention and examples 1 to 4 further describing novel compounds. Example 7 is a comparative example. Example 8 describes the use of the compounds of the invention as flame retardants.
Example 1
Synthesis of melamine magnesium phosphate dihydrate (MMP) C 3 H 7 N 6 O 4 PMg.2H 2 O (MW: 282.5)
[0185] 127.4 g (1.01 mol) of melamine and 58.3 g (1.0 mol) of magnesium hydroxide are suspended in 1.5 l of water with stirring. 115.3 g (1.0 mol) of orthophosphoric acid (85% strength) are added dropwise as dilute aqueous solution to this suspension while stirring. After stirring at 60° C. for 1 hour, a voluminous precipitate is formed. The mixture is subsequently stirred for another 60 minutes, cooled to room temperature, the white precipitate formed is filtered off with suction, washed with water and dried to constant weight at 120° C.
[0186] Yield: 253.0 g corresponding to 90% of theory.
[0187] Elemental analysis:
[0000]
Found:
C:
H:
N:
Mg:
P:
12.70%;
3.67%;
29.69%;
8.47%;
10.87%
Calculated:
C:
H:
N:
Mg:
P:
(12.80%);
(3.90%);
(29.80%);
(8.60%);
(11.0%)
Example 2
Synthesis of melamine zinc phosphate dihydrate (MZP) C 3 H 7 N 6 O 4 PZn.2H 2 O (MW=323.5)
[0188] 2547 g (20.2 mol) of melamine and 1628 g (20.0 mol) of zinc oxide are suspended in 20 l of water with stirring. 2306 g (20.0 mol) of orthophosphoric acid (85% strength) are added dropwise as dilute aqueous solution to this suspension while stirring. After stirring at 60° C. for 1 hour, a voluminous precipitate is formed. The mixture is subsequently stirred for another 60 minutes, cooled to room temperature, the white precipitate formed is filtered off with suction, washed with water and dried to constant weight at 120° C. (product 2-I).
[0189] Yield: 6042.0 g corresponding to 93.4% of theory.
[0190] Elemental analysis:
[0000]
Found:
C:
H:
N:
Zn:
P:
11.6%;
2.83%;
27.20%;
19.83%;
9.45%
Calculated:
C:
H:
N:
Zn:
P:
(11.1%);
(3.4%);
(26.0%);
(20.2%);
(9.6%)
[0191] The product 2-I obtained in this way was tempered at 290° C. for 4 hours (product 2-11), weight loss: 10.4%. C 3 H 7 N 6 O 4 PZn (molecular weight: 287.5).
[0192] Elemental analysis:
[0000]
Found:
C:
H:
N:
Zn:
P:
12.37%;
2.05%;
27.48%;
21.35%;
10.28%
Calculated:
C:
H:
N:
Zn:
P:
(12.53%);
(2.45%);
(29.23%);
(22.74%);
(10.77%)
Example 3
Synthesis of guanidine magnesium phosphate hemihydrate (GMP) CH 6 N 3 O 4 PMg.0.5H 2 O (MW=188.4)
[0193] 91.0 g (0.505 mol) of bisguanidinium carbonate and 58.3 g (1.0 mol) of magnesium hydroxide are suspended in 1.5 1 of water with stirring. 115.3 g (1.0 mol) of orthophosphoric acid (85% strength) are added dropwise as dilute aqueous solution to this suspension while stirring. After stirring at 35° C. for 1 hour, a white precipitate is formed. The mixture is subsequently stirred for another 60 minutes, cooled to room temperature, the white precipitate formed is filtered off with suction, washed with water and dried to constant weight at 120° C.
[0194] Yield: 109.1 g corresponding to 58% of theory.
Example 4
Synthesis of guanidine zinc phosphate (GZP) CH 6 N 3 O 4 PZn (MW=220.4)
[0195] 91.0 g (0.505 mol) of bisguanidinium carbonate and 81.4 g (1.0 mol) of zinc oxide are suspended in 1.5 l of water with stirring. 115.3 g (1.0 mol) of orthophosphoric acid (85% strength) are added dropwise as dilute aqueous solution to this suspension while stirring. After stirring at 60° C. for 1 hour, a voluminous precipitate is formed.
[0196] The mixture is subsequently stirred for another 60 minutes, cooled to room temperature, the white precipitate formed is filtered off with suction, washed with water and dried to constant weight at 120° C.
[0197] Yield: 185.0 g corresponding to 84% of theory.
Example 5
Synthesis of dimelamine zinc bisphosphate monohydrate (M 2 ZP 2 ) C 6 H 16 N 12 O 8 P 2 Zn.H 2 O (MW=529.6)
[0198] 2547 g (20.2 mol) of melamine and 814 g (10.0 mol) of zinc oxide are suspended in 15 l of water with stirring. 2306 g (20.0 mol) of orthophosphoric acid (85% strength) are added dropwise as dilute aqueous solution to this suspension while stirring. After stirring at 60° C. for 1 hour, a voluminous precipitate is formed. The mixture is subsequently stirred for another 60 minutes, cooled to room temperature, the white precipitate formed is filtered off with suction, washed with water and dried to constant weight at 120° C. (product 5-I).
[0199] Yield: 5118 g corresponding to 96.6% of theory.
[0200] The product 5-1 obtained in this way was tempered at 290° C. for 4 hours (product 5-II). Weight loss: 7.3%, with dimelamine zinc diphosphate resulting.
[0201] Elemental analysis:
[0000]
Found:
C:
H:
N:
Zn:
P:
14.67%;
2.40%;
33.58%;
12.67%;
12.34%
Calculated:
C:
H:
N:
Zn:
P:
(14.6%);
(2.85%);
(34.05%);
(13.25%);
(12.55%)
Example 6
Synthesis of dimelamine zinc bisphosphate monohydrate (M 2 ZP 2 ) C 6 H 16 N 12 O 8 P 2 Zn.H 2 O (MW=529.6) by the spray process
[0202] 2547 g of melamine (20.2 mol) and 814 g (10.0 mol) of ZnO are placed in a GPCG 3.1 fluidized-bed granulator from GLATT GmbH. The bed of solid is continuously fluidized by means of a stream of air and a solution produced from 2306 g (20.0 mol) of orthophosphoric acid in 1000 ml of water is sprayed onto it. The fluidized-bed temperature is kept constant in the range 70-80° C., with the granules drying at the same time and a free-flowing, non-dusting granular material being formed. The main fraction (>80%) has a particle size range of 200-400 μm. The residual water content is about 0.5-1%.
[0203] Yield: quantitative.
[0204] The product 6-I obtained in this way was tempered at 290° C. for 4 hours (product 6-II). Weight loss: 8.0%, with dimelamine zinc diphosphate resulting.
[0205] Elemental analysis:
[0000]
Found:
C:
H:
N:
Zn:
P:
14.06%;
2.48%;
33.64%;
12.79%;
11.98%
Calculated:
C:
H:
N:
Zn:
P:
(14.6%);
(2.85%);
(34.05%);
(13.25%);
(12.55%)
Comparative Example 7
Synthesis of dimelamine pyrophosphatozincate [Mel-H] + 2 [ZnP 2 O 7 ] 2− (as described in EP 2 183 314 B1)
[0206] Step I: Preparation of zinc bisdihydrogenphosphate:
[0207] 81.37 g (1 mol) of ZnO are reacted with 230.6 g (2 mol) of orthophosphoric acid (85% strength) in about 500 ml of water while stirring. After stirring at 90° C. for 2 hours, the ZnO had reacted.
[0208] Step II: Reaction of zinc bisdihydrogenphosphate with melamine:
[0209] 252.2 g of melamine are suspended in about 500 ml of water. The zinc bisdihydrogen-phosphate (step I) is added while stirring and the product is filtered off and dried at 120° C.
[0210] Yield: 503.0 g corresponding to 95% of theory.
[0211] Step III: 200 g of product from step II are tempered at 300° C. for 3 hours. Weight loss: 6.5%
[0212] pH measurements and conductivity of 10% strength aqueous suspensions were, after filtration, measured at room temperature on the experimental products (examples 1 to 7). Furthermore, TGA/DSC measurements (heating rate: 10 K/min; N 2 /50) were carried out using a Netzsch STA 409 instrument (see table 1).
[0000]
TABLE 1
Property data for the experimental products
pH values
Example
Product I
Product II
1 (MMP)
6.97
—
2 (MZP)
5.2
5.6
3 (GMP)
10.1
8.48
4 (GZP)
7.48
6.57
5 (M 2 ZP 2 )
4.89
5.5
7 (comparative product*)
4.54
5.5
*prepared as described in EP 2 183 314 B1
[0213] The following zinc compounds were examined further as flame retardants: (see table 2)
[0000]
TABLE 2
Physical properties of zinc compounds
Weight loss at
Conductivity [μS/cm]
300° C. in %
Example
Product I
Product II
Product II
2 (MZP)
136
138
0.5
4 (GZP)
180
82
0.3
5 (M 2 ZP 2 )
255
209
0.3
7 (comparative product*)
490
560
0.6
[0214] The products 2, 4 and 5 according to the invention show improved conductivity values compared to the conductivity value of product 7. The weight losses at 300° C. are likewise lower than in the case of the comparative product 7.
Example 8
Use as Flame Retardant in PA
[0215] Materials: PA 6.6 (Durethan A30S; from LANXESS); glass fibers (ThermoFlow® 671; 10 μm×4 mm; from John Manville); melamine polyphosphate MPP (Melapur 200; from BASF), Zn (2′-hydroxy[1,1′-biphenyl-2-yl-2-phosphinate]) 2 (in-house product), dimelamine zinc diphosphate (example 5).
[0216] The components were compounded and pelletized on a Leistritz ZSE 27HP-44D (φ=27 mm, 44 D) twin-screw extruder. Test specimens (d=1.6 mm) conforming to the standard were made from these pellets by injection molding. The burning test was carried out in accordance with the UL-94 test. The results are shown in table 3.
[0000]
TABLE 3
Flame retardant test
Components
A
B
PA 6.6
47.5%
48.0%
Glass fibers
30.0%
30.0%
Flame retardant components:
(2′-Hydroxy[1,1′-biphenyl-2-yl-2-
12.5%
12.0%
phosphinate]) 2 Zn
MPP
—
10.0%
M 2 ZP 2
10.0%
—
UL-94 test
V-0
V-0 | The present invention relates to azine metal phosphates, compositions containing the same, a process for preparing the same and their use as flame retardants. Typical representatives are (A-H) +) [MtPO 4 ] (+) .2 H 2 O and (Mel-H) (+) [AlP 2 O 7 ] (+) (where A=melamine or guanidine, Mel=melamine and Mt=Mg or Zn). | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 14/537,900 filed on Nov. 10, 2014 by Gerald William Pirkl, titled “SLIDING SHELF CONTAINMENT SYSTEM” (which will issue as U.S. Pat. No. 9,277,819 on Mar. 8, 2016), which is incorporated herein by reference in its entirety, and which claims priority benefit of U.S. Provisional Patent Application No. 61/908,188 filed Nov. 25, 2013 by Gerald W. Pirkl, titled “SLIDING SHELF CONTAINMENT SYSTEM,” and of U.S. Provisional Patent Application No. 61/965,331 filed Jan. 29, 2014 by Gerald William Pirkl, titled “SLIDING SHELF CONTAINMENT SYSTEM.”
FIELD OF THE INVENTION
[0002] The present invention relates to shelves, and in particular to systems and methods for containing objects placed on a sliding shelf.
BACKGROUND OF THE INVENTION
[0003] There are no specifications that relate to dimensional qualities of slide out shelves. Typical sliding shelves are custom built for their needed application. When we think of slide out shelves, kitchen food storage, pots and pans, cleaning products, laundry supplies, garage storage, and other storage applications come to mind. Custom built slide out shelves for these applications are usually constructed from a wood or laminate, or combination thereof. Typical shelves sides are random heights, but the majority of products that I have researched, have what the industry refers to as the height of the width of a credit card. This translates to two and a quarter inches (5.7 cm)—plus or minus. There are custom built installations that have taller sides, and depending on the total height between the floor of the sliding shelf, in question, and the bottom of the shelf above it, may not need this invention. My research shows that the vast majority of owners of typical slide out shelves have a problem with objects falling off the shelves when in operation.
[0004] A Patent Search has been conducted by an independent patent attorney, studying items that relate to ‘Sliding Shelf and Barrier.’ The closest U.S. Pat. No. is 6,039,422. Other sliding shelf patents reviewed are: U.S. Pat. Nos. 7,942,486; 7,806,277; 6,364,136; 5,230,554; 5,037,163; and 4,901,972. His written opinion claims that he did not find any patented products that fit the description of my invention.
[0005] Two Provisional Patents 61/908,188 and 61/965,331, have been submitted for two different versions of this invention. I have included both of them in this one Non-Provisional Submittal.
BRIEF SUMMARY OF THE INVENTION
[0006] The advantages of this invention are to eliminate or greatly reduce materials falling over the edge or sides of slide out shelves.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0007] FIG. 1A is a top oblique view of a sliding shelf, shown with a rail containment system 101 according to one embodiment of the present invention.
[0008] FIG. 1B is an enlargement oblique view of the top left rear corner of the containment shelf of rail containment system 101 .
[0009] FIG. 1C is a front enlargement view of a rail standard of rail-containment system 101 .
[0010] FIG. 1D is a side enlargement view of the rail standard of FIG. 1C .
[0011] FIG. 2A is a top oblique view of a sliding shelf, with a rigid-panel containment system 201 according to one embodiment of the present invention.
[0012] FIG. 2B is an enlargement oblique view of the top right rear corner of containment system 201 , as viewed along line 2 B of FIG. 2A .
[0013] FIG. 2C is a top cross-section view of containment system 201 , as viewed along line 2 C of FIG. 2A .
[0014] FIG. 2D is a front cross-section view of containment system 201 , as viewed along line 2 D of FIG. 2A .
DETAILED DESCRIPTION OF THE INVENTION
[0015] FIGS. 1A, 1B, 1C and 1D relate to the first embodiment corresponding to Provisional Application 61/908,188.
1. The sliding shelf, front, back, sides, and bottom, are existing elements of a conventional sliding shelf unit. 2. Sliding shelves are built in random lengths and widths, and this invention will accommodate units from 12.0 inches to 22.5 inches (30.5 cm to 57.2 cm) in length and 12.0 inches to 30.0 inches (30.5 cm to 76.2 cm) in width. Standard two rail system can accommodate an 8-inch (20.3-cm) sliding-shelf space. A three rail system can accommodate up to an 11-inch (27.9-cm) space. 3. Element 115 (also referred to herein as a containment member)—telescoping rail of metal or rigid material, to accommodate shelf varying widths and lengths. 4. Drawings for this embodiment are: FIG. 1A , FIG. 1B , FIG. 1C , and FIG. 1D .
[0020] FIG. 1A is a top oblique view of a sliding shelf and a rail containment system 101 .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 111 (also referred to herein as a containment-member support)—rail standard—is attached to the shelf sides and back, every four to six inches, with screws, and holds the rails in place. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach rail standards 111 to sides and back of sliding shelf. 4. Element 115 —telescoping rail of metal or rigid material, to accommodate shelf varying widths and lengths. 5. Element 117 —rail end cap of rubberized or plastic material, to close off the ends of the rails, and eliminate sharp edges.
[0026] FIG. 1B is an enlargement oblique view of the top left rear corner of the containment shelf and rail containment system 101 .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 111 —rail standard—is attached to the shelf sides and back, every four to six inches (10 to 15 cm), with screws, and holds the rails in place. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach rail standards 111 to sides and back of sliding shelf. 4. Element 115 —telescoping rail of metal or rigid material, to accommodate shelf varying widths and lengths. 5. Element 117 —rail end cap of rubberized or plastic material, to close off the ends of the rails, and eliminate sharp edges.
[0032] FIG. 1C is a front enlargement view of a rail standard in rail containment system 101 .
[0033] FIG. 1D is a side enlargement view of the rail standard of FIG. 1C .
1. Existing sliding shelf, elements 105 bottom, 107 side, and 109 back. 2. Element 111 —rail standard is a metal or rigid material, approximately ⅛ inch in thickness, by ⅞ inch in width, by 8.0 inches in height (taller standards may hold up to three rails; for example, a first containment member, a second containment member, and a third containment member). 3. Element 113 —self tapping, #8, ½ inch lath screws, attach rail standards 111 (for example, a first containment-member support, a second containment-member support, and a third containment-member support) to sides and back of sliding shelf. 4. Element 115 —telescoping rail of metal or rigid material, to accommodate shelf varying widths and lengths. The outside diameter of these rails may be up to ½ inch in diameter. 5. Element 119 —rail cradle is a metal stamping, or molded protrusion from the rail standard 111 material, made to hold the telescoping rails. The rails can have a thin plasticized material wrapped around the rails at the location of the cradles to provide flexibility when snapping the rail into the cradle. A thicker plasticized material will be wrapped around the inner telescoping rail, to accommodate a snug fitting into the standard size cradle.
[0039] FIG. 2A , FIG. 2B , FIG. 2C , and FIG. 2D relate to the second embodiment corresponding to Provisional Application 61/965,331.
[0040] In FIG. 2A , FIG. 2B , FIG. 2C , and FIG. 2D :
1. The sliding shelf, front, back, sides, and bottom, are existing elements of a conventional sliding shelf unit. 2. Sliding shelves are built in random lengths and widths, and this invention will accommodate units from 12.0 inches to 22.5 inches in length and 12.0 inches to 30.0 inches in width. Standard system can accommodate an 8 inch high sliding shelf space. An 11.0 inch containment panel can accommodate up to a 12 inch high space. 3. Element 135 —containment panel can have elongated screw hole channels to allow panel sliding movement, to accommodate shelf varying widths and lengths. 4. Drawings for this embodiment are: FIG. 2A , FIG. 2B , FIG. 2C , and FIG. 2D .
[0045] FIG. 2A is a top oblique view of a sliding shelf and a rigid panel containment system 201 .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 135 —is a rigid material, approximately ⅛ inch in thickness that may be opaque or transparent. This material is attached to the shelf sides and back, every four to six inches (10 to 15 cm), with screws 113 , and holds the material in place. Elongated screw hole channels allow for panel sliding movement, to accommodate shelf varying widths and lengths. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach containment panels 135 to sides and back of sliding shelf. 4. Element 131 —edge cap is a rigid plasticized material forming a U channel that has an approximate inside dimension of ¼ inch in width by ½ inch legs. This cap clips together the containment panels 135 and filler strips 133 to reinforce the containment panel 135 edges, while at the same time, eliminating sharp edges. Material can accommodate cutting to various lengths with a razor knife or similar. 5. Element 133 —filler strip is an approximate ¾ inch strip of containment panel 135 material, used under the edge cap 131 , at places where overlapping panels do not occur. This strip provides a second thickness to accommodate the snap-on edge cap 131 . The filler strip 133 has an etched grove every ½ inch of its length, to accommodate selecting the approximate length by utilizing snap breaking joints. The filler strip 133 is held in place with a mastic type material of rubberized or plastic material. Filler strip 133 material is also used in 2.0 inch lengths to provide double wall thickness at screw locations, where only a single inside (closest to the center of the shelf) containment panel 135 exists.
[0051] FIG. 2B is an enlargement oblique view of the top right rear corner of the containment shelf and containment system 201 , as viewed along line 2 B of FIG. 2A .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 135 —is a rigid material, approximately ⅛ inch in thickness that may be opaque or transparent. This material is attached to the shelf sides and back, every four to six inches, with screws, and holds the material in place. Elongated screw hole channels allow for panel sliding movement, to accommodate shelf varying widths and lengths. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach containment panels 135 to sides and back of sliding shelf. 4. Element 131 —edge cap is a rigid plasticized material forming a U channel that has an approximate inside dimension of ¼ inch in width by ½ inch legs. This cap clips together the containment panels 135 and filler strips 133 to reinforce the containment panel 135 edges, while at the same time, eliminating sharp edges. Material can accommodate cutting to various lengths with a razor knife or similar. 5. Element 133 —filler strip is an approximate ¾ inch wide strip of containment panel 135 material, used under the edge cap 131 , at places where overlapping panels do not occur. This strip provides a second thickness to accommodate the snap-on edge cap 131 . The filler strip 133 has an etched groove every ½ inch of its length, to accommodate selecting the approximate length by utilizing snap breaking joints. The filler strip 133 is held in place with a mastic type material of rubberized or plastic material. Filler strip 133 material is also used in 2.0 inch lengths to provide double wall thickness at screw locations, where only a single inside (closest to the center of the shelf) containment panel 135 exists.
[0057] FIG. 2C is a top cross-section view of containment system 201 , as viewed along line 2 C of FIG. 2A .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 135 —is a rigid material, approximately ⅛ inch in thickness that may be opaque or transparent. This material is attached to the shelf sides and back, every four to six inches, with screws, and holds the material in place. Elongated screw hole channels allow for panel sliding movement, to accommodate shelf varying widths and lengths. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach containment panels 135 to sides and back of sliding shelf. 4. Element 133 —filler strip is an approximate ¾ inch wide strip of containment panel 135 material, used at places where overlapping panels do not occur. The filler strip 133 has an etched grove every ½ inch of its length, to accommodate selecting the approximate length by utilizing snap breaking joints. Filler strip 133 material is used in 2.0 inch lengths to provide double wall thickness at screw locations, where only a single inside (closest to the center of the shelf) containment panel 135 exists.
[0062] FIG. 2D is a front cross-section view of containment system 201 , as viewed along line 2 D of FIG. 2A .
1. Existing sliding shelf, elements 103 front, 105 bottom, 107 side, and 109 back. 2. Element 135 —is rigid material, approximately ⅛ inch in thickness that may be opaque or transparent. This material is attached to the shelf sides and back, every four to six inches, with screws, and holds the material in place. Elongated screw hole channels allow for panel sliding movement, to accommodate shelf varying widths and lengths. 3. Element 113 —self tapping, #8, ½ inch lath screws, attach containment panels 135 to sides and back of sliding shelf. 4. Element 131 —edge cap is a rigid plasticized material forming a U channel that has an approximate inside dimension of ¼ inch in width by ½ inch legs. This cap clips together the containment panels 135 and filler strips 133 to reinforce the containment panel 135 edges, while at the same time, eliminating sharp edges. Material can accommodate cutting to various lengths with a razor knife or similar. 5. Element 133 —filler strip is an approximate ¾ inch wide strip of containment panel 135 material, used under the edge cap 131 , at places where overlapping panels do not occur. This strip provides a second thickness to accommodate the snap-on edge cap 131 . The filler strip 133 has an etched grove every ½ inch of its length, to accommodate selecting the approximate length by utilizing snap breaking joints. The filler strip 133 is held in place with a mastic type material of rubberized or plastic material. Filler strip 133 material is also used in 2.0 inch lengths to provide double wall thickness at screw locations, where only a single inside (closest to the center of the shelf) containment panel 135 exists.
[0068] General
[0069] Sliding shelves are typically manufactured in random sizes to fit in existing cabinetry space shelf width and length measurements. Typically, the side and back heights of these sliding shelves is 2¼ inches—plus or minus. Custom manufacturers can offer increased wall heights during the initial manufacturing process. This product is produced to retro-fit existing sliding shelves that have not been manufactured with extended walls. Typical wall heights contribute to materials tipping and falling off the shelves. This invention is to solve these tipping and falling item problems. Back to dimensions—the third dimension is to measure the height of the cabinetry space to determine the height and type of products that can be placed on these shelves. If the major problem is to solve the tipping and falling condition, then the first embodiment corresponding to Provisional Application 61/908,188—the telescoping rail system solves the problem. If the shelf is to contain horizontally stacked items, and the sliding of these items causes problems—then the second embodiment corresponding to Provisional Application 61/965,331—the containment panel system works better. This application also solves the item tipping and falling problem. Both product applications have a standard height of 8 inches from shelf bottom to top of containment. Higher containment levels can be produced for both products, to bring the rail system up to 11 inches and the panel system up to 12 inches.
[0070] Materials for the first embodiment corresponding to Provisional Application 61/908,188—telescoping rail system 101 .
a. telescoping rail 115 —stainless steel, steel, other metals, fiberglass, rigid plastic and other high tensile materials. b. rail standard 111 —stainless steel, coated steel, other metals, rigid plastic and other high tensile materials. c. rail end cap 117 —stretchable vinyl material with ½ inch inside length and diameter to fit over the ends of the rail. d. screws 113 —zinc coated, 8-gauge, ½ inch length phil mod truss, lath screws.
[0075] Materials for the second embodiment corresponding to Provisional Application 61/965,331—containment panel system 201 .
a. containment panel 135 —0.125 inch thick polycarbonate, 0.125 inch thick acrylic sheet, materials in clear or colored, 8 inch high×12 inch long and 8 inch high×10 inch long typical panels, 12 inch high panels available. All panels are predrilled, and elongated screw hole channels allow for panel sliding movement, to accommodate shelf varying widths and lengths. b. edge cap 131 —c-line Slide 'N Grip Plastic Binding Bars, 11×¼ inches, cut and shaped for vertical and horizontal ells sections. c. filler strip 133 —same material as the containment panel, ¾×12 inch pieces with scoring every ½ inch to allow for break-off lengths. Filler strips at screw location, for maintaining double thickness, are ¾×2 inch dimensions with predrilled screw holes. d. screws 113 —zinc coated, 8-gauge, ½ inch length phil mod truss, lath screws.
[0080] Assembly for the first embodiment corresponding to Provisional Application 61/908,188—telescoping rail system 101 .
a. measure the inside of the existing sliding shelf. Shelf rail standards 111 , to be installed four to six inches center to center. Shorter length and width shelves will have sides and or back lengths that may have three rail standards 111 as close as four inches center to center. Using a pencil, mark rail standard 111 locations, beginning 2 ¼ inches from each inside corner, to the center of the first rail standard. Divide the remaining distance by 6, and increase to the next whole number. Divide the remaining length by this whole number, to get the spacing for the rail segment. Example for a 30 inch back width shelf—30 minus 4½ (2¼ inches from each corner), equals 25½ inches, divided by 6 is 4¼. Increase to next whole number is 5. Twenty-five and one half inches divided by 5 is a 5.1 inch spacing for this back section. Measure the shelf sides and repeat the same process to obtain spacings. Mark all spacings for rail standards 111 on the shelf bottom, immediately adjacent to the shelf sides and back sections. b. Install rail standards 111 at all spacing marks. Hold a rail standard 111 in place, lining up the space marking with the center of the rail standard 111 , and mark the bottom drill hole. Drill at the bottom hole and install the rail standard (with the rail cradle protrusion to the outside of the shelf) with a screw. Snug up the screw to hold the rail standard 111 in place. Plumb the rail standard 111 to vertical using any 90 degree angle item (like a deck of cards, credit card, note pad, small square, etc.). Mark, drill, and install screw in upper rail standard hole. Check for vertical 90 degrees, and tighten both screws. Complete this process for the remaining rail standard 111 installations. c. Lay out rails next to all three shelf walls. For side sections, partially insert a smaller diameter rail into a large one. Install rail end caps on each end (smaller end cap onto smaller rail, and larger cap onto larger rail end). Lay the side sections into the rail cradles 119 , of the shelf standards 111 , with the larger diameter rail toward the front of the shelf. Assemble the shelf back wall rails (three rail sections will have a small diameter rail on each end). Two rail sections will be the same as the side wall sections. Install rail end caps 117 as necessary, and lay the back rails into the back rail standard 111 rail cradles 119 (two section rails can have the small diameter at either end of the back section). d. Extend the telescoping rails to be flush with the back side of the pull out shelf front. Extend corner telescoping rails to meet at the corners. Pencil-mark each rail at the center of the rail cradle 119 . e. Remove one side rail assembly. Two thicknesses of cradle tape are supplied. Use the thin tape and wrap one revolution over each pencil marking on the large diameter rails. Do the same for the small diameter rails—using the thick tape. Reinstall the side rail assembly, by pressing it down to the bottom of each receiving cradle. Repeat the same process for the other side and back of the shelf.
[0086] Assembly for the second embodiment corresponding to Provisional Application 61/965,331 containment panel system.
a. measure the inside of the existing sliding shelf. Twelve inch deep shelves require only one side 8 inch×12 inch containment panel 135 . Twelve and a half to 22½ inch depth requires two containment panels 135 . Twelve inch wide shelves require only one 8 inch×12 inch containment panel. Twelve and a half to 20.0 inch require 2 containment panels 135 (1-8×12 and 1-8×10 inch). Twenty to 22 inch widths require-2 containment panels 135 (2-8×12 inch). Twenty-two to 30 inch widths require 3 containment panels 135 (2-8×12 and 1-8×10 inch). b. Measure the inside depth of sliding drawer. If the side dimension is 14½ inches or more, install 8×12 side panel at the right rear corner, using the 8 inch side as the panel height. Drill and install the upper screw hole 2¼ inches from the corner. Hold up the second panel (panel closest to the middle of the slide out shelf), against and touching the back of the pull out shelf front 103 . Pencil mark proposed screw holes, in the double thickness portion, 2 inches from the overlap, and evenly along the side panel every 4 to 6 inches. Attach glue side of 2 inch long filler strips 133 to the outside (closest to the pull out shelf side 107 ) of the panel at screw locations where the inside panel is single thickness. Drill and install one screw at a location close to the midpoint of where the panels overlap. This will hold both panels in place while you drill and install the remaining screws at marked points, using the predrilled panel holes as a guide. Repeat the same installation on the opposite pull out shelf side 107 . c. For side depths of less than 14½ inches and more than 12½ inches—temporarily install corner side panel using the top screw hole 2 inches from the corner. Hold up the second 8×12 inch panel and pencil mark screw holes and attach filler strips 133 , as described in 4.b. (above). Remove screw holding the first panel. Hold up both panels and drill and install a screw at a marked hole near the midpoint of the double thickness area. This will hold both panels in place until all screws are installed. Repeat the same installation on the opposite pull out shelf side 107 . d. For back panel installation where the back dimension is less than 14½ inches and more than 12½ inches—start the right rear corner, hold the first panel against the pull out shelf back 109 , with the end touching the installed side panel and repeat the steps contained in 4.c. above. e. For back panel installation where the dimension is less than 22 inches and more than 14½ inches—start the first 8×12 panel against the pull out shelf back 109 right rear corner. Drill and install the upper screw hole 2¼ inches from the corner. Hold up the second 8×12 panel (panel closest to the middle of the slide out shelf), against and touching the left rear corner. Pencil mark proposed screw holes at the mid point of the double thickness portion, and evenly along the back panel every 4 to 6 inches. Attach glue side of 2 inch long filler strips to the outside (closest to the pull out shelf back 109 ) of the inside panel at screw locations where the inside panel is single thickness. Drill and install one screw at a location close to the midpoint of the panel. This will hold both panels in place while you drill and install the remaining screws at marked points, using the predrilled panel holes as a guide. f. For back panel installation where the dimension is less than 30 inches or more than 24 inches—install an 8×12 panel against the pull out shelf back 109 in each corner. Drill and install the upper screw hole 2¼ inches from each corner. Center the third 8×10 panel in the gap between the first two panels. Pencil mark all screw hole locations and install filler strips as necessary in the gap between the first two panels. Attach glue side of 2 inch long filler strips to the outside (closest to the pull out shelf back 109 ) of the panel. Drill and install one screw at a marked location close to the midpoint of the panel. This will hold all panels in place while you drill and install the remaining screws at marked points, using the predrilled panel holes as a guide. g. Before you install the top and front edge cap 131 , additional filler strips must be installed to provide a gripping surface for the edge cap 131 . All areas along the edge cap 131 , must receive filler strips to make the edge a double thickness. Starting on the side panel at the right rear corner of the sliding shelf—this single section will receive a filler strip 133 , on the side closest to the sliding shelf center. Hold the break-off strip against the single panel and mark the length with a pencil. If this mark falls in between break-off points, go to the next shortest break-off point on the strip and (using two pliers) break the strip at that location. That will allow the strip to fit into the gap. Install the glue side to the inside of the corner side panel. Moving toward the front of the sliding shelf, repeat the measurement, break off, and glue attachment for the strip on the outside of the second panel. Then repeat the measurement, break-off, and glue attachment for the vertical front strip. Move to the other side and repeat the same procedure. Now move to the back right corner of the shelf, and repeat the measurement, break-off, and glue and attach the strip on the inside of the first panel attached to the back of the shelf. Then repeat the measurement, break-off, and glue attachment for the entire horizontal strip. As you move toward the shelf left back corner, alternate sides (when there are two or three back panels) when applying filler strips 133 . h. When all filler strips are installed, there should be a continuous double thickness of containment panels 135 and filler strips 133 , all along the top of the containment panels 135 , and from the top of the front two containment panels 135 , down to the top of the pull out shelf front. i. Begin installing edge caps 131 . Use the ell edge cap 131 consisting of the vertical and horizontal angle—to be applied to the front two corners of the containment panels. Measure the distance from the top of the front two containment panels 135 , down to the top of the pull out shelf front. Using a razor knife, carefully cut the ell edge cap 131 , to the measurement. Install edge cap 131 , starting at the top of the pull out shelf front. Spread the bottom corner legs of the edge cap, and insert it over the containment panel 135 , and filler strip 133 , at the bottom of the vertical section. Gently apply pressure on the back of the edge cap 131 , as you move up the edge cap. When the edge cap is fully seated on the vertical portion of the panel, gently apply pressure on the back of the edge cap 131 , as you move horizontally toward the rear corner of the shelf. When this edge cap is fully seated, install the horizontal ell edge cap 131 on the back corners, using the same procedure. There will be gaps between the ell edge caps 131 on the tops of the panels on the sides and back of the shelf. Measure the gap distance, and (using a razor knife) carefully cut and install a section of straight edge cap 131 , to the measurement. Two straight sections of edge cap 131 may be required on the back panels of wide shelves. Apply pressure to all edge cap 131 sections to complete the installation. | Mechanisms and methods to install upper restrictive barriers onto existing pull-out shelves to prevent or decrease the likelihood of the shelf contents from falling over the back or sides of the shelf. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method and a measuring device for measuring stress forces in refiners having refining discs that define a refining gap for refining material.
BACKGROUND OF THE INVENTION
[0002] Refiners are used for refining fibrous material. The refiner generally comprises refining members in the form of discs rotating in relation to each other and between which refining material passes from the inner periphery of the refining members where it is supplied, to the outer periphery of the refining members through a refining gap formed between the refining members. One of the refining discs is often stationary while the other rotates. The refining discs are generally composed of segments provided with bars. The inner segments have a coarser pattern and the outer segments have a finer pattern in order to achieve fine refining of the refining material.
[0003] To obtain high quality refining material when refining fibrous material, the disturbances in operating conditions that, for various reasons, constantly occur must be corrected by constant adjustment of the various refining parameters to optimal values. This can be achieved, for instance, by altering the supply of water to produce a greater or lesser cooling effect, by altering the flow of refining material or adjusting the distance between the refining members, or a combination of these measures. To enable the necessary adjustments and corrections to be made an accurate determination of the energy transmitted to the refining material is required, as well as of the distribution of the energy transmitted over the surface of the refining members.
[0004] To determine the energy/power transmitted to the refining material it is known to endeavour to measure the shearing forces that occur in the refining zone. What is known as a shearing force occurs when two surfaces move in relation to each other with a viscous liquid between the surfaces. Such shearing force is also created in a refiner when refining wood chips mixed with water. It can be imagined that the wood chips are both sheared and rolled between the refining discs, as well as collisions occurring between chips and bars. The shearing force depends, for instance, on the force bringing the discs together and on the friction coefficient. The normal force acting on the surface also varies with the radius.
[0005] In International Application No. WO 00/78458 a method and a measuring device are known for measuring stress forces in such refiners, the device comprising a force sensor that measures the stress force over a measuring surface constituting a part of a refining disc and in which the measuring surface comprises at least parts of more than one bar and is resiliently arranged in the surface of the refining disc. However, it has been found that this measuring device is very sensitive to temperature fluctuations, which are usual in the applications under discussion, and it therefore often gives incorrect values for the force, which thus cannot be used to control the refining process. Furthermore, a value for the force in only one direction is obtained with this measurement. Another drawback is that other forces also appear that affect the refining segments, such as the normal forces, which are not taken into account.
[0006] One object of the present invention is to solve the problems mentioned above and to thus provide a method and a measuring device that gives a more complete and correct result than previously known devices.
SUMMARY OF THE INVENTION
[0007] In accordance with the present invention, these and other objects have now been realized by the invention of a method of measuring stress forces in refiners including a pair of refining discs juxtaposed with each other and forming a refining gap for refining material therebetween, the pair of refining discs including at least one refining surface including a plurality of bars for refining the material within the refining gap, the at least one refining surface including a measuring surface comprising a predetermined portion of the at least one refining surface including at least a portion of at least a pair of the plurality of bars, the method comprising resiliently mounting the measuring surface in the at least one refining surface and simultaneously measuring both the magnitude and direction of stress forces in the plane of the measuring surface. Preferably, the simultaneously measuring comprises measuring the stress forces in a first direction by means of a first force sensor and measuring the stress forces in a second direction by means of a second force sensor, the first direction being angularly displaced with respect to the second direction, and determining the magnitude and direction of the stress forces by measuring the stress forces in the first and second directions. In a preferred embodiment, the simultaneously measuring comprises measuring the stress forces in a first direction by means of a first pair of first sensors disposed opposite each other to provide counter-directed readings and measuring the stress forces in the second direction by means of a second pair of second sensors disposed opposite each other to provide counter-directed readings, the first pair of first sensors and the second pair of second sensors being disposed perpendicularly to each other.
[0008] In accordance with one embodiment of the method of the present invention, the simultaneous measuring includes compensating for eccentric normal stress forces on the measuring surface.
[0009] In accordance with another embodiment of the method of the present invention, the method includes measuring stress forces directed perpendicularly to the measuring surface. Preferably, the measuring of the stress forces directed perpendicularly to the measuring surface includes combining the force exerted by steam pressure inside the refiner and the force exerted by fiber pressure from the refining material. In another embodiment, the measuring of the stress forces directed perpendicularly to the measuring surface includes measuring the force exerted by fiber pressure from the refining material and compensating for the force exerted by steam pressure inside the refiner.
[0010] In accordance with another embodiment of the method of the present invention, the simultaneous measuring of both the magnitude and direction of the stress forces in the plane of the measuring surface comprises calculating both the magnitude and direction from the first and second force sensors, and including controlling the refining process based thereon.
[0011] In accordance with the present invention, this and other objects have now been realized by the discovery of apparatus for measuring stress forces in refiners including a pair of refining discs juxtaposed with each other and forming a refining gap for refining material therebetween, the pair of refining discs including at least one refining surface including a plurality of bars for refining the material within the refining gap, the at least one refining surface including a stress measuring member comprising a measuring surface comprising a predetermined portion of the at least one refining surface including at least a portion of at least a pair of the plurality of bars, the stress measuring member being resiliently mounted in the at least one refining surface and comprising at least a first set of force sensors for simultaneously measuring both the magnitude and direction of stress forces in the plane of the stress measuring member. Preferably, the apparatus includes compensating means for compensating for eccentric normal forces in the plane of the stress measuring member that will effect the measuring.
[0012] In accordance with one embodiment of the apparatus of the present invention, the apparatus includes an additional stress measuring member for measuring stress forces perpendicular to the stress measuring member.
[0013] In accordance with another embodiment of the apparatus of the present invention, the first set of force sensors comprises a first force sensor for measuring the stress forces in a first direction and a second force sensor for measuring the stress forces in a second direction, the first direction being angularly displaced with respect to the second direction, whereby the magnitude and direction of the stress forces in the plane of the stress measuring member are determined from the readings of each of the first and second force sensors. In a preferred embodiment, the first set of force sensors includes a pair of said first force sensors for measuring the stress forces in the first direction and a pair of the second force sensors for measuring the stress forces in the second direction.
[0014] In accordance with another embodiment of the apparatus of the present invention, the stress measuring member comprises a first body connecting the first set of force sensors to the stress measuring member, the first body comprising a first tubular resilient member disposed around the central axis of the stress measuring member, the first set of force sensors being disposed on the first tabular resilient member. Preferably, the stress measuring member includes a second set of force sensors. In a preferred embodiment, the stress measuring member comprises a second body connecting the second set of force sensors to the stress measuring member, the second body comprising a second tubular resilient member disposed around the central axis of the stress measuring member, the second set of force sensors being disposed on the second tubular resilient member. Preferably, the second set of force sensors and the second body comprise compensating means for compensating for eccentric normal forces.
[0015] In accordance with another embodiment of the apparatus of the present invention, the apparatus includes an additional stress measuring member for measuring stress forces perpendicular to the stress measuring member, the additional stress measuring member comprising at least three force sensors disposed on the first tubular resilient member.
[0016] In accordance with another embodiment of the apparatus of the present invention, the apparatus includes an additional stress measuring member for measuring stress forces perpendicular to the stress measuring member, the additional stress measuring member comprising at least three force sensors disposed on the second tubular resilient member.
[0017] In accordance with another embodiment of the apparatus of the present invention, the additional stress measuring member comprises means for measuring the stress force exerted perpendicular to the stress measuring member.
[0018] In accordance with another embodiment of the apparatus of the present invention, the first set of force sensors comprise strain gauges.
[0019] In accordance with the method of the present invention, measuring is performed over a measuring surface that constitutes a part of a refining disc, the measuring surface comprising at least parts of more than one bar and being resiliently arranged in the surface of the refining disc, and forces in the plane of the measuring surface are measured and both the magnitude and the direction of the force are measured simultaneously. The measuring device in accordance with the present invention comprises members for measuring the stress force over the measuring surface, which in turn constitutes at least a first set of force sensors for simultaneously measuring both the direction and magnitude of forces in the plane of the measuring surface.
[0020] The measurement in accordance with the method of the present invention is preferably performed with the aid of at least two force sensors, one of which is arranged to measure in an X-direction and the other of which is arranged to measure in a Y-direction, and the magnitude and direction of the force influencing the measuring surface are determined as the resultant reading of the two force sensors. It should be pointed out that the X-direction and Y-direction, respectively, do not necessarily imply two directions forming a right angle with each other, but these directions may form any angle at all as long as they do not coincide with each other.
[0021] The present invention thus enables measurement of the shearing forces in two directions, thereby enabling both the magnitude and direction of the resultant shearing force to be determined in any direction at all, which is advantageous.
[0022] In accordance with a preferred embodiment of the present invention the measurement is performed with the aid of at least four force sensors arranged in pairs opposite each other so that the two sensors in each pair give counter-directed deflection or readings, the pairs are arranged at right angles to each other to measure in an X-direction and a Y-direction, and the magnitude and direction of the force are determined as the resultant reading, i.e. the measured stress forces of each pair of force sensors. The use of sensors arranged in pairs giving counter-directed readings offers the important advantage that a value can be obtained for the stress force that is not affected by occurring temperature fluctuations. This is achieved by utilizing the difference between the readings of the force sensors in the relevant pair, measured on each occasion, as the value of the stress force in each direction. This value can then be utilized to calculate the magnitude and distribution of the power transmitted to the refining material and these calculations can then be used to control the refining process. In this context reference is also made to Swedish Patent Application No. 0102845-5 filed by the present applicant.
[0023] Utilizing pairs of counter-directed sensors in the manner defined in the present invention offers the advantage that any measuring errors are halved for each direction.
[0024] In accordance with another advantageous feature of the present invention, the measurement of these forces in the plane of the measuring surface also includes compensation for any eccentric normal forces on the measuring surface that would affect such measurement.
[0025] In accordance with an additional advantageous feature of the method of the present invention forces directed at right angles to the measuring surface are also measured. This method preferably includes measurement of the normal force exerted by a combined pressure consisting of the steam pressure inside the refiner and the fiber pressure from the refining material. An alternative choice is to measure a normal force that is a result of only the pressure of the fiber mat.
[0026] The measuring device in accordance with the present invention comprises suitable devices for performing the method.
[0027] In accordance with a particularly advantageous embodiment of the present invention, the force sensors comprise strain gauges. A particular advantage of this is that the actual measuring device will be relatively small and low, thus allowing it to be fitted directly in the refining segment.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The present invention will now be described with reference to the following detailed description, which refers to the accompanying schematic drawings, in which:
[0029] FIG. 1 is a top perspective view of a refining segment included in a refining disc which is provided with measuring devices in accordance with the present invention,
[0030] FIG. 2 is a schematic representation of a basic layout in accordance with the present invention,
[0031] FIG. 3 is a side, elevational, cross-sectional view of a first embodiment of a measuring device in accordance with the present invention,
[0032] FIG. 4 is a schematic representation of a basic layout of the embodiment illustrated in FIG. 3 ,
[0033] FIG. 5 is a side, elevational, cross-sectional view of a second embodiment of a measuring device in accordance with the present invention,
[0034] FIG. 6 is a schematic representation of a basic layout of the embodiment illustrated in FIG. 5 , and
[0035] FIG. 7 is a top, elevational schematic cross-sectional view of the thin-walled tubular parts of the first and the second body, and the strain gauges arranged thereon.
DETAILED DESCRIPTION
[0036] Referring to the drawings, FIG. 1 shows a part of a refining disc in the form of a refining segment 1 , provided with a pattern comprising a number of bars 3 extending substantially in the radial direction. Measuring devices 4 in accordance with the present invention are also shown schematically in this figure. These measuring devices preferably have a circular measuring surface 2 with a diameter in the order of 30 mm, for example, but the measuring surface may alternatively have a different geometric shape. The measuring devices are preferably arranged at different radial distances from the center of the refining disc, and segments at different distances from the center preferably also have measuring devices. The measuring devices can also advantageously be displaced peripherally in relation to each other to enable them to better determine the power distribution in the refiner and thus better control the refining process. When a measuring device is influenced by forces, each of the force sensors will generate a signal that is proportional to the load.
[0037] The measuring device in accordance with the present invention functions in accordance with the principle illustrated in FIG. 2 . Shown thereon is a measuring surface 2 in the form of part of the surface of a refining segment, provided with a number of bars 6 , or at least parts thereof. The measuring device includes an attachment element in the form of a rod 10 , with the aid of which the various parts of the device are secured and which also joins the various parts of the measuring device to each other and to the measuring surface 2 . The rod has two fulcrums, a first, upper fulcrum 8 for a first body 5 and a second, lower fulcrum 9 for a second body 7 . Compare also FIGS. 3 and 5 . The first body 5 is provided with a first set of power sensors ( 12 in FIGS. 3 and 5 , respectively). This first body connects the measuring surface 2 with the rod 10 so that, when the refining disc is subjected to a shearing force F s , the torque M 1 in the first fulcrum 8 or torque point will be:
M 1 =F s ·I 1 (1)
where I 1 is the distance between the measuring surface 2 of the measuring device and the fulcrum 8 .
[0038] The second body 7 with a second set of force sensors ( 22 in FIGS. 3 and 5 , respectively) is arranged in conjunction with the second, lower fulcrum 9 . This second body is connected to the rod 10 so that, when the refining disc is subjected to a shearing force F s , the torque M 2 in the second fulcrum 9 or torque point, will be:
M 2 =F s ·I 2 (2)
where I 2 is the distance between the measuring surface 2 of the measuring device and the fulcrum 9 .
[0039] The torques in the fulcrums are obtained with the aid of the readings of the force sensors and, on the basis of these, the shearing force F s can be calculated.
[0040] Thanks to the arrangement with a second set of force sensors it is possible to compensate the values obtained for the shearing force F s with regard to any asymmetric or eccentric normal forces, i.e. forces in the normal direction, perpendicular to the measuring surface which, due to their point of attack not being the center of the measuring surface 2 since they are displaced from the center, influence the force sensors as if they were shearing forces. The following equations are obtained:
M 1 =F s ·I 1 +F N ·I N (3)
M 2 =F s ·I 2 +F N ·I N (4)
where F N is in this case an eccentric normal force and I N is the distance between the central axis and the point of attack of the eccentric normal force.
[0041] The equations (3) and (4) provide the following expression for the shearing force, which is utilized in the measuring device:
F s = M 2 - M 1 I 2 - I 1 ( 5 )
[0042] If no eccentric normal force occurs to influence the measuring surface, it would be sufficient with only one set of force sensors and one body.
[0043] FIG. 3 shows a preferred embodiment of a measuring device in accordance with the present invention. The measuring device 4 comprises a measuring surface 2 provided with bars 6 , or parts of bars, which measuring surface constitutes a part of a refining segment as illustrated in FIG. 1 . As is also clear in FIG. 1 , the measuring device preferably has a circular measuring surface. The measuring device and the measuring surface are movably arranged in the refining segment 1 , in all directions.
[0044] The measuring surface 2 is in direct contact with a first, upper body 5 extending inside the device. At its lower side this first body is shaped as a thin-walled tube 15 . The material is chosen to be somewhat resilient. A cross section through the thin-walled tube section can therefore be likened to a spring, as illustrated in FIG. 4 . Strain gauges are arranged on the outside of the thin-walled tube section, which form a first set of force sensors 12 . It is actually the thin-walled, somewhat resilient tube section that, together with the strain gauges, forms the force sensors, but for the sake of simplicity the term force sensor is used in this description primarily as a designation for the strain gauges or equivalent members. The strain gauges are preferably arranged axially and when the thin-walled tube is subjected to a load it is slightly deformed so that it influences the strain gauges. These are, in turn, connected to some suitable strain gauge bridge that generates a corresponding signal. The thin-walled tube section 15 is pre-stressed with a tensile force so that it does not risk collapsing when subjected to loading.
[0045] Inside the tube section extends a rod 10 with a spherical top, which rod forms the previously mentioned attachment element. The first body 5 is journalled on the spherical top which thus functions as a fulcrum for the body 5 and forms the first fulcrum 8 . This embodiment comprises four sensors arranged symmetrically in relation to a center line extending through the measuring surface 2 and through the rod 10 . The sensors 12 are preferably arranged with 90° spacing (see also FIG. 7 ). They are arranged in pairs opposite each other so that the sensors in a pair will give counter-directed deflection/reading when influenced by a force. When the pressure on the measuring surface 2 increases, the load on one of the sensors will increase while at the same time it will decrease on the other sensor in a pair. The stress force can therefore be calculated on the basis of the difference between the readings measured at any one time on respective force sensors in a pair. It would naturally be possible to arrange the sensors differently in relation to each other and still have their respective readings be counter-directed. Said pairs of sensors are also arranged perpendicular to each other for measuring in an X-direction and a Y-direction, i.e. in a plane parallel with the measuring surface 2 . This permits measurement of forces in all directions in a plane parallel with the measuring surface, the magnitude and direction of the force being determined as the resultant of the readings of respective pairs of force sensors (see also FIG. 4 ).
[0046] A second, lower body 7 is arranged below the first, upper body 5 and outside its tubular part 15 . This second body also has a thin-walled tubular part 17 , arranged outside and concentric with the tubular part 15 of the first body 5 and with the rod 10 , and functioning in a corresponding manner, i.e. as a spring. Strain gauges are also arranged on the outside of the second thin-walled tubular part 17 . These strain gauges form a second set of force sensors 22 and are preferably arranged axially. They are four in number and are arranged symmetrically in relation to a center line extending through the measuring surface 2 and through the rod 10 . In other respects they are arranged in the same way and function in the same way as the sensors 12 of the upper body 5 , i.e. they are arranged in pairs and measure forces in X- and Y-direction, see also FIG. 7 . However, in the example illustrated the fulcrum 9 for the lower body 7 is formed by the central point of a resilient plate or sheet 18 arranged below the body 7 and connected to the rod 10 so that the rod extends through the center of the plate.
[0047] The fulcrum 9 may alternatively be designed as a waist on the rod 10 , preferably arranged immediately above the point at which the plate 18 is located (see also FIG. 5 ).
[0048] The rod 10 preferably has screw threading and the first, upper body 5 is preferably screwed onto the rod. The second, lower body 7 may suitably be attached to the rod by means of a nut.
[0049] The measuring device in the example illustrated also comprises means for measuring forces directed at right angles to the measuring surface, i.e. normal forces, i.e. forces in Z-direction as illustrated in FIG. 4 . The normal force is a resultant of the steam pressure in the refiner and the pressure exerted against the measuring surface (and the refining segment) by the fiber mat formed by the refining material. For this purpose the measuring surface is resiliently arranged in a direction perpendicular to the measuring surface, also illustrated schematically in FIG. 4 . In accordance with one embodiment the normal forces can be measured with the aid of additional strain gauges forming force sensors 32 , arranged on one or other of the tubular parts, 15 or 17 , preferably axially between the already existing sensors, as illustrated schematically in FIG. 7 . To obtain a fairly correct measurement, at least three force sensors should be used for measuring the normal force, and these should be uniformly distributed. However, the use of four sensors is preferred, as shown in FIG. 7 , or possibly more.
[0050] The internal parts of the measuring device described above are arranged in a protective sensor housing 20 . This housing is provided with an opening at the top, which is adjacent to the surrounding refining segments, and which is closed off from the refining material, by the measuring surface 2 and a resilient seal 16 between the measuring surface and the side walls of the sensor housing. The housing is also closed off at the bottom, towards the stator of the refiner or segment holder if such is used, by a lid 11 . The seal 16 is of a particularly suitable, somewhat resilient material, e.g. rubber, so that it can permit the small movements that the shearing forces give rise to in the measuring surface and still provide a good seal preventing steam and pulp from penetrating into the device. The seal preferably also has a dampening effect on, inter alia, the vibrations occurring during operation. In this context it may be mentioned that the load can vary considerably over the refining zone from values in the order of 20N to in the order of 150N, for instance. In the present case, at an estimated mean value of approximately 40N, displacements of the measuring surface that can be measured in the order of hundredths of a millimeter are obtained.
[0051] FIGS. 5 and 6 illustrate a second embodiment of the present invention in which compensation can take place for the steam pressure that exists in the refiner and which constitutes a part of the normal force pressure on the measuring surface that is measured with the measuring device in accordance with the first embodiment. As mentioned earlier the normal force F N , which affects the measuring surface, comprises both the force from the fiber pressure F Fib exerted by the fiber mat formed by the refining material in the refiner, and also the force from the steam pressure F S that prevails inside the refiner. It is often of interest to obtain a measurement of the fiber pressure on its own. Parts in this figure corresponding to parts in FIGS. 3 and 4 have been given the same reference numerals. Thus, this embodiment also comprises a first body 5 and a second body 7 , each provided with thin-walled tubular parts 15 and 17 , respectively, on which a first and second set of force sensors, 12 and 22 , respectively, are arranged. The second tubular part 17 is provided with special force sensors for measuring the normal force, in the form of strain gauges 32 preferably arranged axially between the already existing sensors, as illustrated schematically in FIG. 7 . Alternatively, these sensors for measuring the normal force could be placed on the tubular part 15 of the first body 5 . It also comprises a rod 10 and a plate-like spring member 18 , preferably in the form of four crossing legs whose function here is to secure the various parts of the measuring device from below. The internal parts of the measuring device are also located in a protective sensor housing 20 . Contrary to the embodiment in FIG. 3 , however, the lid closing off the sensor housing from the stator or segment holder is designed so that a connection exists between the upper side of the measuring surface and the upper side of the surrounding refining segment by means of an open channel 13 arranged between the side walls of the sensor housing 20 and the surrounding refining segment 1 . The aim is that compensation can be achieved for the existing steam pressure when the normal force affecting the measuring surface 2 is calculated. For this purpose the existing steam pressure shall also affect the parts of the measuring device that measure the perpendicular pressure in the direction opposite to the normal pressure, i.e. from below. The lid 11 may thus be made in two parts, an outer part 23 provided with channels and an inner, movable part 24 having a gap between it and the stator/segment holder. The rod 10 is also shaped so that a gap exists between it and the stator/segment holder. Steam can thus penetrate to the gap 25 formed above the stator/segment holder and thus influence the inner part 24 , rod 10 and force sensors 32 on the part 17 , or possibly other members that have been mentioned and can form said members for measuring perpendicular forces. The steam pressure acting on the measuring surface and the steam pressure acting from below thus cancel each other out and a measurement of the actual fibre pressure can be obtained.
[0052] It should be pointed out that the method and device for measuring perpendicular forces or normal forces, with or without compensation for the steam pressure, can be used as a separate invention and possibly combined with other devices for measuring shearing forces.
[0053] It is also possible to omit the compensation for eccentric normal forces and have only one set of force sensors, one body and one fulcrum in the device.
[0054] It should also be mentioned that it is perfectly possible to use other types of force sensors than strain gauges in combination with thin-walled resilient tubes.
[0055] Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. | Methods for measuring stress formed in refiners having refining discs that between them define a refining gap for refining material between bars arranged on the refining discs are disclosed. The measuring is performed over a measuring surface that constitutes a part of a refininig disc, the measuring surface comprising at least parts of more than one bar and being resiliently arranged in the surface of the refining disc. Furthermore, forces in the plane of the measuring surface are measured and both the magnitude and the direction of the forces are measured simultaneously. The invention also relates to a device for performing the method. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims priority under 35 U.S.C. §371 from International Patent Application No. PCT/FR2006/002526, filed Nov. 15, 2006, and French Patent Application Nos. 0511567, filed Nov. 15, 2005 and 0651174, filed Apr. 3, 2006.
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to the field of magnetic rotary position sensors for angles of up to 360°, and more particularly to position sensors for measuring the angular position of a steering column for a motor vehicle, without this application being exclusive.
Sensors which detect the angle on the basis of a magnetic field have many advantages:
no mechanical contact with the moving part, and therefore no wear, insensitivity to soiling, low production cost, long life span.
There is known in the prior art the patent EP1083406 which describes a rotary sensor, having a ring magnet and two magnetosensitive elements which measure the radial component of the field generated by the magnet and which leads to two square-wave sinusoidal signals which, after decoding, serve to detect the position over 360 degrees.
The disadvantage of this solution is the presence of two probes, which may give rise to a measurement error due to the incorrect placement of one probe relative to the other. In addition, the presence of two integrated circuits which are offset spatially by 90° increases the final cost of the sensor since the printed circuit surface area may be large and the number of connections is increased.
Also known in the prior art are probes which make it possible to measure the two components of the magnetic field in one plane (Hall-effect probe, for example MLX90316 from Melexis, or magnetoresistive probes).
Also known in the prior art is the U.S. Pat. No. 6,316,935 which describes a position sensor which can rotate through 360° and which uses a magnetoresistive probe in order to determine the angular position of a disc magnet which is magnetised essentially diametrically (see FIG. 1 ). In said patent, the magnetoresistive probe which is sensitive to the direction of the magnetic field generated by the magnet is placed below the magnet and essentially on its axis of rotation. The probe measures the components Bx and By of the magnetic field on the axis of rotation of the magnet (see FIG. 2 ). Such an arrangement of the magnet and of the probe limits the use of such a sensor. This is because, in the particular case of using a rotary sensor to measure the angular position of a system with a through-shaft, such as a steering column for example, such an arrangement of the magnet and of the probe is not possible due to the fact that the size of the steering column prevents it from being possible to position the magnetosensitive element on its axis of rotation.
SUMMARY OF THE INVENTION
The present invention proposes to solve the abovementioned problems by making it possible to use two components of the magnetic field (radial and tangential or axial and tangential) which are measured simultaneously at a single point (in physical terms, it is considered that the measurements are carried out at a single point if the distance between the measurement points of the two components of the magnetic field is less than 5 mm) outside the axis of rotation of a ring magnet or disc magnet which is diametrically magnetised, so as to ascertain its angular position even though this angle does not correspond to the angle of the magnetic field (note: the direction of the magnetic field is “aligned” with the angular position of the magnet only if the measurement is carried out on the axis of this same magnet). The solution described below thus makes it possible to reduce the cost of the sensor and to increase the reliability of the measurements while advantageously adapting it to different geometric configurations, in particular in the case of a device with a through-shaft.
If we consider any point in space around a ring or disc magnet which is diametrically magnetised, the radial component and the axial component of the magnetic field generated by this magnet are two sine curves which are in phase, whereas the tangential component is a sine curve which is 90° out of phase with respect to the two other components of the magnetic field (see FIG. 3 ). It is therefore possible to use a pair of components of the magnetic field which are 90° out of phase (tangential and radial or tangential and axial) to decode the angle of the magnet, using the following formula:
α ( t ) = arctan ( V 1 ma x V 2 ma x V 2 ( t ) V 1 ( t ) )
where:
—angle of rotation
V 1 —radial or axial component of the magnetic field
V 1max —amplitude of V 1
V 2 —tangential component of the magnetic field
V 2max —amplitude of V 2
The decoding of the angular position of the magnet on the basis of these two components, the amplitudes of which are generally different, requires the standardisation of the two components used so as to be able to perform the arctangent calculation in order to deduce the angle therefrom. These decoding and standardisation functions are carried out either by a separate element ( 4 ) or directly by a probe (e.g.: MLX 90136) which integrates the measurement of the two components of the field, the decoding of the angle and the standardisation of the two components of the field.
The economic advantage is then that of using a single integrated circuit of the SMD (Surface Mount Device) type with a much smaller printed circuit surface area than when using two probes positioned 90° apart around the magnet.
In one preferred embodiment, the magnetosensitive elements consist of at least one pair of magnetosensitive sensors, the sensitivity axes of which are parallel, said sensors of one pair being magnetically coupled by a ferromagnetic yoke which is perpendicular to said sensitivity axes, said yoke being arranged in a plane perpendicular to the axis of rotation or in a plane parallel to a plane passing through the axis of rotation. By way of example, the magnetosensitive elements consist of a probe with an integrated flux concentrator MLX90136 produced by Melexis, which comprises four co-planar sensors (the sensitivity axes of which are therefore parallel). These four Hall elements are placed below the edges of a ferromagnetic disc constituting a yoke. They are spaced apart by 90°. The magnetic field bends in the vicinity of the ferromagnetic disc (which has a high relative permeability). The magnetic field lines are perpendicular to the surface of the magnetic flux concentrator and they pass through the Hall elements, thus making it possible to measure the two magnetic field components in the plane of the probe. Furthermore, the magnetic field measured by the Hall elements is amplified because the field lines are concentrated in the vicinity of the ferromagnetic disc. The Hall elements on each axis (X and Y or X and Z) are connected to a signal processing circuit which delivers the voltage difference of the two Hall elements (which eliminates the axial component of the magnetic field), which is amplified and sampled by an analogue/digital converter. The digital signal processing circuit multiplies each component by a programmable gain (which makes it possible to obtain sine curves of substantially equal magnitude) and carries out the various compensations (with regard to offset, orthogonality, variation in the parameters of the probe relating to temperature) before performing the division and the arctangent calculation. The angle obtained is available at the output of the integrated circuit, for example in the form of a voltage proportional to this angle.
This invention will advantageously use ring magnets made of plastoferrite with diametrical anisotropy, which makes it possible to obtain very good performance for the lowest possible cost. Furthermore, the use of a magnet with anisotropy facilitates the magnetisation process. This is because the performance (linearity of the output signal) of the sensor is directly dependent on obtaining a good diametrical magnetisation. The use of isotropic magnets is also possible, but the magnetisation process for obtaining a “good” diametrical magnetisation of the magnet is more complex. This is because the magnetisation field necessary for diametrically magnetising a ring magnet is easily obtained with a simple coil which is passed through by a current, but a curvature of the field lines is produced due to the difference in magnetic permeability between air and the material to be magnetised, which curvature follows the following relationship concerning refraction at the boundary between two media:
tan
(
α
1
)
tan
(
α
2
)
=
μ
r
1
μ
r
2
This curvature translates into a magnetisation of the material which is not diametrical and therefore into a distortion of the two components measured, as shown in FIG. 10 . These two signals are not two sine curves which are 90° out of phase, which during the decoding phase translates into a very considerable non-linearity as can be seen in this same FIG. 10 which shows the signal decoded on the basis of the two components of the magnetic field.
In the case of an isotropic material, in order to correct and compensate this curvature of the field lines inside the magnet which leads to a “poor” diametrical magnetisation, the external shape of the magnet, instead of being circular, will advantageously be selected to be of an essentially elliptical shape (see FIG. 11 ).
It is also possible when using the probe MLX 90316 to program this probe in such a way as to partially compensate the non-linearity error. The compensation takes place via a programming of different gains over the full course of the sensor. In the case of such programming, there is shown in FIG. 12 :
the signal decoded by a non-linear transfer function; the non-linearity of the decoded signal.
In the case of an isotropic magnet or a magnet with radial anisotropy, it is also possible to magnetise the magnet progressively with a radial magnetisation which follows a sinusoidal law at the periphery of the magnet. This manner of magnetisation makes it possible to avoid the error on the magnetisation direction due to the refraction of the magnetic field lines, which occurs in the case of a diametrical magnetisation.
In the case where the application requires a redundancy of the output signals, it is of course possible to envisage doubling the system by using a second measurement point which is offset angularly from the first with respect to the axis of rotation. Preferably, it will therefore be possible to have two similar housings which each integrate the measurement and decoding of two signals, one tangential and the other resulting from the combination of radial and axial components, with a specific gain adjustment, so as to deliver two independent angular position signals.
In the case of an application such as measuring the position of a steering column associated with a steering wheel which performs a rotation over several revolutions, it may prove necessary to measure a course greater than 360°. It is then possible to use the sensor according to the invention by associating it with a motion reducer so as to reduce the rotation over several revolutions to a rotation less than or equal to one revolution at the sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood with reference to the various figures.
FIG. 1 shows the field lines generated by a diametrically magnetised disc magnet,
FIG. 2 shows the 3 magnetic induction components at a point located on the axis of rotation of the magnet—point O shown in FIG. 1 ,
FIG. 3 shows the 3 magnetic induction components at a point located outside the axis of rotation of the magnet,
FIG. 4 shows a general view of the present invention,
FIG. 5 shows a view of a rotary sensor using the radial and tangential components of the induction,
FIG. 6 shows the 3 magnetic induction components at any point in space for the configuration described in FIG. 5 (measurement point on the median plane of the magnet),
FIG. 7 shows a view of a rotary sensor using the axial and tangential components of the induction,
FIG. 8 shows the field lines inside the magnet upon magnetisation for a material with a relative permeability (μr) equal to 1,
FIG. 9 shows the field lines inside the magnet upon magnetisation for a material with a relative permeability (μr) equal to 1.2,
FIG. 10 shows the radial and tangential components of the magnetic induction and also the non-linearity of the signal measured on a “diametrically” magnetised isotropic circular ring magnet,
FIG. 11 shows the radial and tangential components of the magnetic induction and also the non-linearity of the signal measured on a “diametrically” magnetised isotropic magnet having an essentially elliptical external shape,
FIG. 12 shows the signal obtained on an isotropic magnet and decoded with a non-linear transfer function,
FIG. 13 shows a magnet with progressive radial magnetisation,
FIG. 14 shows the 3 components of the magnetic induction at any point in space around the magnet,
FIG. 15 shows the integration of the sensor according to the present invention integrated with a reducer so as to be used for a multiple-revolution application,
FIG. 16 shows the four Hall elements placed on the edge of a magnetic flux concentrator,
FIG. 17 shows the magnetic field lines in the presence of the flux concentrator,
FIG. 18 shows a block diagram of the signal processing of a probe using four Hall elements and a magnetic flux concentrator,
FIGS. 19 and 20 show a secondary embodiment according to the invention, in which the magnet is a tile,
FIG. 21 shows a secondary embodiment according to the invention, in which the probe comprising the magnetosensitive elements is located inside the hollow cylindrical magnet,
FIGS. 22 , 23 and 26 show secondary embodiments according to the invention, in which the probe is associated with a shield for shielding against external magnetic fields,
FIGS. 24 and 25 show a secondary embodiment according to the invention, in which the sensor is associated with a bearing.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows the typical field lines obtained with a diametrically magnetised disc magnet. The field lines are shown on a plane passing through the centre of the magnet and co-linear with the magnetisation direction of the magnet. In FIG. 2 and FIG. 3 , the radial (Bx), tangential (By) and axial (Baxial) components of the magnetic induction are shown respectively for a measurement point located on the axis of rotation of the magnet and at a point located on a radius larger than the outer radius of the magnet. FIG. 2 shows that the components X and Y of the magnetic induction on a point of the axis as a function of the rotation of the magnet are of equal amplitude, and that the axial component is zero regardless of the position above the magnet. With regard to FIG. 3 , it can be seen that the 3 components of the magnetic induction are other than 0 and that the radial and axial components are in phase whereas the tangential component is 90° out of phase with respect to the two others.
FIG. 4 shows the sensor according to the present invention, which comprises an essentially radially magnetised ring-shaped permanent magnet ( 1 ); at any point in space, this magnet generates a magnetic field having radial or axial ( 3 ) and tangential ( 2 ) components which are measured by two magnetosensitive elements, the signals from which are then processed by a processing element ( 4 ) which carries out the decoding and also the standardisation of the two components in order to output an electrical signal which is proportional to the angular position of the magnet.
FIG. 5 shows the configuration of the sensor, for use as a steering column sensor, using the radial and tangential components of the magnetic field generated by the magnet ( 1 ). This configuration uses a diametrically magnetised ring magnet which is mounted directly on the axis of the steering column or of the drive shaft ( 5 ). The plane of the probe will advantageously be placed such a way that it is co-planar with the plane of symmetry of the magnet so as to limit the influence of the axial component of the magnetic field in the case of a positioning error of the probe ( 6 ). This is because, for this particular configuration, the axial component of the magnetic field is zero and therefore, even if the probe is not perfectly positioned, the projection of the axial component onto the tangential component measured by the probe will be zero. In this particular configuration, use is made of a probe which integrates the measurement of the two components of the field, the standardisation of the two components and the decoding of the angle on the basis of the two signals which are 90° out of phase. According to one preferred variant, the magnet will be directly adhesively bonded to the column.
FIG. 7 shows a sensor configuration for use as a steering column sensor, using the axial and tangential components of the magnetic induction generated by the magnet ( 1 ). For this configuration, there is no position of the probe which leads to an obvious cancellation of the radial component which in the case of poor positioning of the probe ( 4 ) causes a contribution to the tangential component which may give rise to a distortion of the output signal. For such a configuration, the position of the probe will therefore advantageously be selected so as to reduce to a minimum the radial component while retaining an optimal amplitude on the two other components. In this particular configuration, use is made of a probe which integrates the measurement of the two components of the field, the standardisation of the two components and the decoding of the angle on the basis of the two signals which are 90° out of phase.
FIG. 8 shows the field lines, upon magnetisation with a view to obtaining a diametrical magnetisation, inside and outside a ring magnet with a relative permeability equal to 1 (μr=1 such as that of air). The field lines pass through the magnet without undergoing any deformation, which allows a perfect diametrical magnetisation.
FIG. 9 shows the field lines, upon magnetisation, inside and outside a ring magnet with a relative permeability equal to 1.2. The field lines undergo a deformation as they pass through the magnet, said deformation being due to the difference in relative permeability between air (μr=1) and the magnet (μr=1.2 in the present case). This deviation of the field lines therefore translates into a poor diametrical magnetisation of the magnet. In order to solve this problem, it is of course possible to use an anisotropic magnet with a preferred magnetisation direction. In the case of an isotropic magnet, it will be difficult to obtain a good diametrical magnetisation, which will lead to the results shown in FIG. 10 . In order to correct and compensate this magnetisation error, a magnet having an essentially elliptical external shape may be used. The components of the induction which are measured or such a magnet are shown in FIG. 11 . A marked improvement can be seen in the non-linearity caused by the difference in refraction of the field lines and also the change in the measurement gap.
In the case of an isotropic ring magnet which is magnetised with a poor diametrical magnetisation due to the refraction of the field lines at the surface of the magnet during the magnetisation process, it is possible when using a programmable probe to program a non-linear transfer function which makes it possible to partially compensate the non-linearity of the signal (see FIG. 12 ).
In the case of an isotropic magnet or a magnet having radial anisotropy, FIG. 13 shows a ring magnet with a sinusoidal variation of the remnant magnetisation over 1 revolution. Such a configuration leads to the signals shown in FIG. 14 .
FIG. 15 shows the sensor according to the present invention integrated with a ring magnet integrated with the output of a reducer so as to measure a course greater than 360° of an element located at the input of the reducer. This may be used for example in the case of a steering column which requires detection of the angular position of the steering wheel over several revolutions. The example of FIG. 15 shows the sensor associated with a planetary reducer, but any other reducing system can be used provided that the integration is compatible with the application.
FIG. 16 shows the flux concentrator ( 19 ) and the four Hall elements ( 15 , 16 , 17 and 18 ) placed below the edge of the element 19 and spaced apart by 90°. Each of the Hall elements ( 15 , 16 , 17 and 18 ) has a detection axis oriented along the axis Z perpendicular to the plane XOY of the flux concentrator ( 19 ). The elements 15 and 16 measure the magnetic induction along the axis X and the elements 17 and 18 measure the magnetic induction along the axis Y. The four elements ( 15 , 16 , 17 and 18 ) and the yoke ( 19 ) of the flux concentrator ( 19 ) are mounted in a housing which encapsulates the assembly so as to form a single component.
FIG. 17 shows the magnetic field lines in the presence of a magnetic flux concentrator ( 19 ), in a vertical section along one of the axes X and Y. The field lines bend and become perpendicular to the surface of the concentrator, passing through the Hall elements ( 17 ) and ( 18 ).
FIG. 18 shows a block diagram of the signal processing. The signals V x and V y are obtained from the Hall elements 15 (which delivers the signal V z1 ), 16 (which delivers the signal V z2 ) and 17 (which delivers the signal V z3 ), 18 (which delivers the signal V z4 ). The differences are amplified by the gain ( 21 ) (including the electronic gain and the gain due to the ferromagnetic concentrator 19 ), they pass through the analogue/digital converter ( 22 ) and they arrive at the digital signal processing block ( 23 ): the correction of the measured amplitudes is carried out by this block, which delivers the output signal (V out ).
In FIGS. 19 and 20 , the magnet ( 1 ) is a cylindrical tile which has a diametrical magnetisation. This diametrical orientation can describe an infinite number of directions relative to the tile ( 1 ). FIGS. 19 and 20 are two examples of directions which this magnetisation may assume. In FIG. 19 , the magnetisation is radial to the centre of the magnet ( 1 ), whereas it is tangential in FIG. 20 . These examples are therefore not in any way limiting in nature.
FIG. 21 shows a secondary embodiment in which the probe ( 6 ) is located inside the cylindrical and hollow magnet ( 1 ) forming a ring. It may in fact be beneficial to allow the probe ( 6 ) to be placed in this way if the dimensions of the system receiving the sensor require it.
FIGS. 22 and 23 show the sensor described by the invention associated with a shield ( 81 ) for shielding against external magnetic fields. It may in fact be beneficial to ensure an insensitivity to external fields if the sensor is intended to be used in a polluted environment. In FIG. 22 , the magnet ( 1 ) is mounted on a ferromagnetic yoke ( 71 ) which is itself mounted on a shaft 5 . The probe ( 6 ) is placed in front of the magnet ( 1 ) oriented so as to measure the tangential and radial components of the magnetic field. It is surrounded by a shield ( 81 ) made of a material which is commonly used for this type of function, such as alloys with a high magnetic permeability by way of non-limiting example. Since the probe ( 6 ) is insensitive to axial magnetic fields, the shield ( 81 ) will preferably be placed around the probe ( 6 ) in the plane of the magnet. In FIG. 23 , the same shielding function associated with the same sensor is found, but here the probe ( 6 ) is placed in such a way as to measure the tangential and axial components of the magnetic field. In this embodiment, and since the probe ( 6 ) is insensitive to radial magnetic fields, the shield ( 81 ) will preferably be placed around the probe in the plane tangential to the magnet ( 11 ). Placed in this way, the shield ( 81 ) makes it possible to ensure an insensitivity to external magnetic fields during the measurement. In FIGS. 22 and 23 , this shield ( 81 ) is in the form of a folded thin plate of small dimensions.
This shield ( 81 ) shown in FIGS. 22 and 23 is an advantageous solution which allows a minimum size, but is in no way limiting. All the shielding means known to the person skilled in the art can of course be integrated with the position sensor. For instance, in FIG. 26 , the shield ( 81 ) is represented by a ring which completely surrounds the assembly consisting of the magnet ( 1 )+probe ( 6 ).
Since the sensor according to the invention is particularly suitable, in a non-limiting manner, for applications comprising a through-shaft, it may be envisaged to place the sensor in the direct vicinity of a bearing, for example a ball bearing. FIGS. 24 and 25 show two embodiments of the sensor described by the invention associated with a ball bearing ( 91 ). The probe ( 6 ) of FIG. 24 is sensitive to tangential and axial fields, whereas the probe ( 6 ) in FIG. 25 is sensitive to tangential and radial fields. In both cases, the ball bearing ( 91 ) is placed in the vicinity of the sensor so as to form a compact assembly. Ideally, the magnet ( 1 ) and the dimensions of the sensor, and also the position of the sensitive elements, should be selected as a function of the dimensions of the bearing ( 91 ) and the total size of the assembly consisting of the sensor and the bearing ( 91 ). | An angular position sensor includes a moving element consisting of at least one essentially cylindrical permanent magnet turning about it axis, at least two magnetosensitive elements and at least one processing circuit furnishing a signal dependent on the absolute position of the moving element The magnetosensitive elements are located essentially at the same point and in that they measure the tangential component of the magnetic field and the radial and/or axial component of the magnetic field for furnishing 2 sinusoidal signals that are essentially 90° out of phase. | 6 |
[0001] This application is a Continuation of PCT/EP2005/000199, filed Jan. 12, 2005, and claims the priority of DE 10 2004 008 389.4, filed Feb. 20, 2004, the disclosures of which are expressly incorporated by reference herein.
BACKGROUND AND SUMMARY OF THE INVENTION
[0002] The invention relates to a variable stroke valve drive for an internal combustion engine having an intermediate lower and a crank arm and cam arrangement for actuating the lever.
[0003] In German Unexamined Patent DE 101 23 186 A1, in which a mechanical regulating means for adjusting the lift of a gas exchange valve, a variable stroke valve drive of an internal combustion engine is described. The mechanical regulating means is characterized in that the rotational speed control and load control of the internal combustion engine are regulated not via a throttle valve but instead via the valve lift of the gas exchange intake valves. To achieve this, the mechanical regulating means has an intermediate lever which is mounted at one end so it is slidingly movable on a crank path of a crank arm and has a working cam with a null lifting cam and a lifting cam at the other end. The working cam is operatively connected here to a gas exchange valve via an intermediate element, namely a drag lever. Furthermore, the mechanical regulating means has a camshaft with which the intermediate lever is rotated against the elasticity of the restoring spring about a point near the crank arm, so that the portions between the null lifting cam and the lifting cam, which are operatively connected to the intermediate element, are shifted. Despite the rotating camshaft, the gas exchange valve remains closed as long as the contact point and/or the contact line is between the intermediate lever or the null lifting cam and a rolling element arranged on this intermediate lever. Furthermore, the mechanical regulating means has a second adjusting element, namely an eccentric shaft, which acts on the intermediate lever near the crank arm. Due to the rotation of the eccentric shaft, the intermediate lever in the crank arm is shifted parallel to the crank path so that the effective component between the lifting cam and the no-load lifting cam is altered. The portion of the lifting cam with respect to the cam elevation may thus be increased or decreased. An increase in the lifting cam portion corresponds to an increase in the gas exchange valve lift. A reduction in the lifting cam portion corresponds to a reduction in the gas exchange valve lift until as described above, only the no-load lifting cam portion is operatively connected to the intermediate lever.
[0004] One disadvantage of the embodiment described here is the relatively high wear on the intermediate lever on all contact areas with corresponding friction partners such as the restoring spring, the crank arm, and the drag lever.
[0005] The object of the present invention is to provide a generic variable stroke valve drive with minimized wear.
[0006] This object is achieved through the features in the by using instead of a camshaft, a cam plate whose radius increases or decreases steadily over the circumference with respect to the axis of rotation.
[0007] In the state of the art described above, the camshaft has a base circle, i.e., a circumferential area of the cam with a constant radius. As long as the base circle of the camshaft is operatively connected to the intermediate lever, the intermediate lever remains at rest, i.e., it is not rotated. Due to the fact that it is stationary, there is a transition from adhesion to sliding on the contact areas of the intermediate lever with a spring element, the intermediate element and the crank arm in the transition from the base circle of the cam to the cam elevation, thus resulting in heavy wear on the contact areas.
[0008] With an embodiment of the present invention, however, the intermediate lever is kept permanently in motion with rotation of the inventive cam plate. Due to the constant motion of the intermediate lever, tangential excitation of the spring element due to breakaway is prevented, while avoiding the high acceleration forces that are transmitted via the contact points, at which unfavorable lubrication conditions prevail due to a static surface pressure. In other words, through the proposed constant vibrational movement of the intermediate lever when using a cam plate in an advantageous manner is there a constant oil input between the contact areas of the contact partners, consisting of the intermediate lever, the spring element and the intermediate element. Thus the fictional losses and the component wear are greatly reduced and the lifetime of the variable stroke valve drive is greatly prolonged. Secondly, the intermediate lever rotational accelerations due to the uninterrupted rotational movement are greatly reduced, so the gas exchange valves can be opened more quickly and the charge cycle, as well as processing of the mixture, are improved. Thirdly, resonance effects of the restoring spring are ruled out due to constant active leg lengths, such as those which occur with a stationary intermediate lever in contact with the base circle, and the variable stroke valve drive is more stable mechanically, i.e., is less susceptible from the standpoint of vibration technology. Furthermore, as a result of this, the spring element may be designed with smaller dimensions, so that much higher rotational speeds can also be achieved in conjunction with the reduced acceleration forces of the intermediate lever, as described previously.
[0009] Due to the inventive use of the cam plate, the variable stroke valve drive thus becomes much more resistant to wear and more stable mechanically, i.e., there are reduced acceleration forces and vibrational forces, thereby reducing technical vibration problems and allowing the rotational speed of the internal combustion engine to be increased with no problem.
[0010] Through support of the intermediate lever on the crank path via a roller element, the internal friction in the entire variable stroke valve drive is reduced again significantly. Due to the proposed embodiment, wear is thus further reduced and the lifetime and/or service life is increased. Fuel savings due to the reduced internal friction of the variable stroke valve drive can be mentioned as another positive effect.
[0011] Further, through arrangement of the crank path as an arc of a circle, a purely rotational movement of the intermediate lever is possible in operation of the second adjusting device. The fulcrum here is the point near the crank arm and thus when using the first roller element this is the axis of rotation of the first roller element. There are no translational movements and thus sliding movements, which are associated with wear. Furthermore, spontaneous (i.e., without delay) opening and closing of the gas exchange valve are possible.
[0012] With an embodiment in which the base circle of a camshaft is simulated, a closed gas exchange valve is made possible without resulting in the aforementioned disadvantages of a traditional known camshaft.
[0013] An embodiment in which the ramp between the null lifting cam and the lifting cam is integrally molded reduces the acceleration forces that occur in the variable stroke valve drive in the transition from the no-load lifting cam to the lifting cam. The resulting constant opening and closing accelerations of the intermediate lever allow a higher rotational speed of the internal combustion engine.
[0014] With an intermediate element configured as a swing lever or a tilt lever, the variable stroke valve drive is largely free of play and maintenance. A hydraulic valve play equalizing element is preferably used.
[0015] An embodiment in which the inventive variable stroke valve drive crank arm is located in a cylinder head allows a compact and stiff design of the variable stroke valve drive.
[0016] Using a second adjusting device, the forces and/or torques to be applied in adjusting the gas exchange valve lift can be achieved with no problem. Of course the cam plate may have any technically feasible contour.
[0017] Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 shows a section through an variable stroke valve drive in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0019] The variable stroke valve drive 1 includes an intermediate lever 2 which is mounted at one end so it is slidingly movable on a crank path 3 a of a crank 3 which is arranged in a stationary mount in a cylinder head 16 . On the opposite end, the intermediate lever 2 has a working cam 4 with a null lifting cam 4 a and a lifting cam 4 b, a ramp 4 c being formed between the null lifting cam 4 a and the lifting cam 4 b. In FIG. 1 , the null lifting cam 4 a is operatively connected to a fourth roller element 15 , a roller of an intermediate element 5 , a drag lever. The operative connection is a linear contact between the roller and the working cam 4 , which is largely planar in a plane perpendicular to the plane of the drawing. The intermediate lever 5 is mounted at one end on a play equalizing element 18 , preferably a hydraulic valve play equalizing element and on a gas exchange valve 6 at the other end. The gas exchange valve 6 and the play equalizing element 18 are mounted in the cylinder head 16 . The crank path 3 a has a defined radius. An axis of rotation 15 a of the fourth roller element 15 is the center of curvature of the crank path 3 a when the null lifting cam 4 a and the fourth roller element 15 are operatively interconnected.
[0020] On the crank end, the intermediate lever 2 has a first roller element 12 with a first axis of rotation 12 a, which is also in linear contact with the crank path 3 a perpendicular to the plane of the drawing. A second roller element 13 is arranged coaxially with the first axis of rotation 12 a and is operatively connected to a second adjusting device 10 . The second adjusting device 10 in the present exemplary embodiment has a cam plate with which the crank end of the intermediate lever 2 can be shifted in parallel to the crank path 5 a in a controlled or regulated manner. For example, the cam plate may be an eccentric plate or cam but any other contours may also be used without any problem.
[0021] Approximately in the middle between the first and second roller elements ( 12 , 13 ) and the working cam 4 , the intermediate lever 2 has a third roller element 14 . A first adjusting device 7 acts on this third roller element 14 . The first adjusting device 7 includes a cam plate 11 with a circumferential surface 11 a, which rotates about an axis of rotation 11 b. The cam plate 11 has a radius that changes steadily over the circumferential surface 11 a and thus differs from a camshaft due to the lack of a base circle, i.e., a circumferential surface section 11 a having a constant radius.
[0022] The gas exchange valve 6 is opened and closed cyclically with the first adjusting device 7 , and in addition to the null lifting cam 4 a, the lifting cam 4 b is also operatively connected to the fourth roller element 15 . The absolute lift of the gas exchange valve 6 is set with the second adjusting device 10 . If the linear contact (contact area 17 a ) of the fourth roller element 15 is on the null lifting cam 4 a, then the gas exchange valve lift is zero, the linear contact over the ramp 4 c is shifted to the working cam 4 b, so the lift of the gas exchange valve 6 is increased to a maximum. To implement null lifting with the null lifting cam 4 a, its contour is largely shaped as a circular section,
[0023] This ensures that the first adjusting device 7 is always operatively connected to the intermediate element 2 via the third roller element 14 , so a spring element 9 , a leg spring, is provided and is attached in a stationary attachment to the cylinder head 16 and always presses against the intermediate lever 2 with a first contact area 17 a close to the working cam 4 . Of course other contact points may also be provided on the intermediate element 2 .
[0024] The exemplary section here through a preferred embodiment of the variable stroke valve drive 1 shows a section of a single gas exchange valve 6 of the internal combustion engine. The gas exchange valve 6 may be an intake gas exchange valve as well as an exhaust gas exchange valve. Furthermore, the internal combustion engine may have several gas exchange valves 6 for the intake and/or exhaust ends per cylinder. This means that the variable stroke valve drive may be used on both the intake end and the exhaust end. The number of cylinders of the internal combustion engine has no direct influence on the function of the variable stroke valve drive 1 . By combining multiple devices 7 , 10 , e.g., by using one shaft for several cam plates 11 , a variable stroke valve drive 1 may be provided for each intake side and/or exhaust side of a cylinder bank.
[0025] The play equalizing element 18 , which in the present exemplary embodiment is a hydraulic equalizing element, may also be implemented by other design variants, e.g., mechanical equalizing elements. Furthermore, the intermediate element 5 may be a tilt lever, for example, instead of a swing lever. The intermediate element 5 may be either in direct contact with the working cam 4 , in which case the surface near the intermediate element is to be shaped with a radius, or the contact is accomplished via the fourth roller element 15 . The second adjusting device 10 may also be a pusher rod adjustment and/or a hydraulic or electromechanical adjusting device in addition to being an eccentric adjustment. The spring element 9 , which is a leg spring in the present exemplary embodiment, may also be replaced by spring elements having a different geometric design, e.g., a plate spring. The roller elements 12 through 15 are preferably ball mounted or needle mounted and a friction bearing is also possible. The intermediate lever 2 is preferably made of sheet metal or manufactured by a casting method. The crank 3 may be detachably or nondetachably connected to the cylinder head 16 .
[0026] During operation of the internal combustion engine, the cam plate 11 of the first adjusting device 7 is rotated about the axis of rotation 11 b in largely phase-locked manner with a crankshaft. However, to be able to completely take advantage of the fuel savings of the variable stroke valve drive, a camshaft adjusting unit, for example, may be provided, varying the relative rotational position of the first adjusting device 7 in relation to the crankshaft rotational position within certain limits. Due to the rotational movement of the first adjusting device 7 , the intermediate lever 2 , which is pressed by the spring element 9 against the cam plate 11 , is rotated about the point 8 near the crank. If the first roller element 12 is omitted, the point near the crank arm then drifts. If the first roller element 12 is used, then the midpoint of rotation (point 8 near the crank) of the intermediate lever 2 is the midpoint of the first roller element 12 , which advantageously does not drift in rotation of the intermediate lever 2 . The working cam 4 here does not drift in this way. The working cam 4 here is shifted over the fourth roller element 15 in the second contact area 17 b. As long as the second contact area 17 b is in the vicinity of the null lifting cam 4 a, there is no movement of the gas exchange valve. If the second adjusting device 10 is adjusted and the first roller element 12 is shifted in the direction of the arrow, the second contact area 17 b migrates over the ramp 4 c into the vicinity of the lifting cam 4 b. In this case, the gas exchange valve 6 is opened and then closed again.
[0027] When using a camshaft for the first adjusting device 7 , as described in the state of the art, the intermediate lever 2 stands still when the base circle of the camshaft is operatively connected to the third roller element 14 . In this period of time, lubricant is forced out of the contact areas 17 a, 17 b in particular due to the static surface pressure. As the cam is raised, the intermediate lever 2 is pivoted again and in the first moment of movement there is dry friction and/or mixed friction in the contact areas 17 a, 17 b. Due to this initial dry and/or mixed lubrication, there is enormous wear, which is prevented with the present invention.
[0028] The feature essential the present invention is explained again below with its essential advantages.
[0029] Due to the use of the inventive cam plate 11 , the intermediate lever 2 is always in motion so there cannot be any static surface pressure in the contact areas 17 a, 17 b and constantly adequate lubrication of the contact areas 17 a, 17 b is ensured at all times. The inventive design thus results in much less friction and much less wear. In addition, the opening and closing accelerations of the intermediate lever are greatly reduced due to the use of the cam plate 11 , so that much higher rotational speeds of the internal combustion engine are possible. Another advantage is the possibility of smaller dimensions of the spring element 9 . Furthermore, resonance effects in the spring element 9 due to the constant movement of the intermediate lever 2 are avoided. By optimizing the spring element 9 , higher rotational speeds can again be achieved while at the same time minimizing friction and minimizing wear.
[0030] The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit arid substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
LIST OF REFERENCE NOTATION
[0000]
1 . Variable stroke valve drive
2 . Intermediate lever
3 . Crank arm
3 a. Crank path
4 . Working cam
4 a. Null lifting cam
4 b. Lifting cam
4 c. Ramp
5 . Intermediate element
6 . Gas exchange valve
7 . First adjusting device
8 . Point near crank
9 . Spring element
10 . Second adjusting device
11 . Cam plate
11 a. Circumferential surface
11 b. Axis of rotation
12 . First roller element
12 a. First axis of rotation
13 . Second roller element
14 . Third roller element
15 . Fourth roller element
15 a. Second axis of rotation
16 . Cylinder head
17 a. First contact area
17 b. Second contact area
18 . Play equalizing element | A variable stroke valve drive for an internal combustion engine, including an intermediate lever which is slidingly arranged on a crank path of a crank arm the intermediate lever has a working cam with null lifting cam and lifting cam portions. The working cam contacts a gas exchange valve via an intermediate element. A first adjustment element rotates the intermediate lever against a spring element around a point located near the crank, the intermediate lever being displaceable along the crank path by a second adjustment element. The first adjustment element is provided with a cam plate whose radius continuously increases or reduces on a circumference with respect to an axis of rotation. The inventive variable stroke valve drive substantially reduces wear in a valve drive. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a continuation patent application of U.S. patent application Ser. No. 14/062,058 filed on Oct. 24, 2013, which is a continuation patent application of U.S. patent application Ser. No. 13/595,844 filed on Aug. 27, 2012, which is a continuation patent application of U.S. patent application Ser. No. 12/837,389 filed on Jul. 15, 2010, which is a continuation patent application of U.S. patent application Ser. No. 11/724,452 filed on Mar. 15, 2007, now U.S. Pat. No. 7,781,019 issued on Aug. 24, 2010, the entire contents of which are incorporated herein by reference.
STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to cast in place concrete walls and, more particularly, to a method of forming a cast in place concrete wall wherein the resultant wall has a substantially smooth and uniform outer surface texture.
2. Description of the Related Art
As is well known in the construction industry, concrete is a commonly used material for the fabrication of walls and barriers. The desirability of the use of concrete as a construction material is attributable to certain characteristics that concrete possesses in comparison to other construction materials. More particularly, walls and barriers may be quickly and easily constructed through the use of concrete, with the concrete also imparting a high level of durability to such structures. In addition, the use of concrete for the fabrication of walls and barriers offers a high level of design flexibility since the concrete may be molded into many different shapes and arrangements. The concrete is also easily transportable to construction sites via concrete transport trucks.
Many of the concrete walls that are constructed in accordance with the current state of the art are referred to as cast in place walls. A concrete cast in place wall is typically constructed on-site rather than being manufactured at an off-site facility and subsequently transported to the construction site. The fabrication of a cast in place concrete wall typically begins with the construction of a concrete wall form. Subsequent to the construction of such form, concrete is poured thereinto and is given time to cure. Once the concrete has cured, the corresponding wall form is removed from the fully formed concrete structure. Upon the removal of the form, the exposed walls of the concrete structure may be sandblasted to apply a finishing texture thereto.
One of the deficiencies associated with the currently known cast in place wall construction methodology is that the resultant wall or other structure tends to have a roughened surface texture upon the removal of the form therefrom. In this regard, there tends to be slight inconsistencies in the overall finish of the wall or other structure, such inconsistencies being caused by any one of a number of different factors, including inconsistencies in the form work, sandblasting, finishing, concrete and/or the placing or pumping of the concrete into the form. Further, small holes or other indentations are often found throughout the exposed surfaces of the wall or other structure, such holes or other indentations being formed as a result of the entrapment of air during the forming process. These holes or other indentations are undesirable, in as much as they diminish the aesthetic appeal of the wall or other structure.
In order to avoid the surface finish inconsistencies highlighted above, there has been developed in the prior art a method of creating uniform texture concrete walls. In accordance with this methodology, the concrete wall is “pre cast,” with the cast face of the wall being side down and the wall being erected into place through the use of a crane. However, this particular process is not well suited to forming concrete structures wherein multiple faces or sides of the structure are to be provided with a substantially uniform texture. The present invention addresses this need in the art by providing a methodology for forming concrete structures such as walls or barriers having substantially smooth or uniform exterior surface textures.
BRIEF SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, there is provided a method of forming a cast in place concrete wall having a substantially uniform exterior surface texture. As indicated above, concrete is a commonly used construction material that comprises aggregate of various shapes and sizes disposed in cement. The method of the present invention includes the initial step of constructing or assembling a concrete wall form in a suitable size and shape, and thereafter pouring a first concrete mixture into the wall form. The concrete poured from such first mixture is allowed to partially cure once poured into the form. Once the concrete is at least partially cured, the wall form is removed from the resultant base structure. Subsequent to the form removal, the cured concrete structure is subjected to a procedure which creates a roughened surface texture on the exposed exterior surfaces thereof. Such roughened surface texture may be formed through the use of a form retarder, a spray on retarder, sand blasting, acid washing, and/or chemical etching.
Subsequent to the roughening of the exposed surfaces of the base structure, a finishing mixture is then applied to such roughened surfaces. In accordance with the present invention, the finishing mixture may be created by separating the aggregate from a portion of the remainder of the first mixture used to initially form the base structure. However, such finishing mixture may also be formed by separating the aggregate from a second mixture of the concrete, wherein such second mixture is a separate batch of concrete from the first mixture. The finishing mixture, however derived, is applied to the initially formed base structure to create a smooth/uniform texture over the roughened exterior surfaces thereof. As will be recognized, the fully cured finishing mixture ultimately defines the exposed exterior surfaces of the concrete structure (e.g., a wall, barrier, etc) comprising the combination of the base structure having the finishing mixture applied thereto.
As is apparent from the foregoing, the present invention provides a method of constructing a concrete structure such as a cast in place wall having substantially more uniform exterior surface textures then those which can be achieved by the formation of cast in place walls using presently known techniques. By separating at least the large aggregate from the concrete batch used to create the finishing mixture, the application of such finishing mixture to the initially formed base structure is operative to cover any inconsistencies that may otherwise have been present in such base structure. It is contemplated that the finishing mixture may be applied through the use of a float which is operative to work the finishing mixture into any holes or other detents disposed in the initially formed base structure. The surface of the finishing mixture may also be troweled to achieve a harder texture. The exposed surface of the finishing mixture itself may also be acid washed after the finishing mixture is allowed to harden to a prescribed level.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which:
FIG. 1 is a perspective view of a cast in place concrete wall constructed in accordance with techniques known in the prior art;
FIG. 2 is a perspective view of a section of concrete poured into a wall form;
FIG. 3 is a perspective view of a section of the concrete from FIG. 2 , wherein the wall form has been removed and a roughened surface has been applied to the cured concrete base structure;
FIG. 4 is a perspective view of a section of the concrete base structure from FIG. 3 , wherein a finishing mixture is being applied to the roughened surface at the base structure; and
FIG. 5 is a perspective view of a concrete wall constructed in accordance with the method of the present invention.
Common reference numerals are used throughout the drawings and detailed description to indicate like elements.
DETAILED DESCRIPTION OF THE INVENTION
The detailed description set forth below is intended as a description of the presently preferred embodiment of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the functions and sequences of steps for constructing and operating the invention. It is to be understood, however, that the same or equivalent functions and sequences may be accomplished by different embodiments and that they are also intended to be encompassed within the scope of the invention.
As indicated above, cast in place concrete walls provide numerous advantages over walls constructed from other building materials. In this regard, cast in place walls may be quickly and easily constructed, and provide substantial flexibility in the size and shape of the wall. However, as also indicated above, cast in place walls constructed in accordance with most prior art fabrication methodologies often include an undesirable rough, non-uniform exterior surface texture. In this regard, when the concrete is poured into the corresponding wall form, air may become entrapped in small pockets within the concrete. When the concrete cures and the wall form is removed, these air pockets may appear as inconsistencies on the exposed surfaces of the resultant wall. These inconsistencies in the wall surface are typically considered to be aesthetically undesirable. FIG. 1 illustrates a cast in place wall constructed through the use of known, prior art methodologies. As is shown in FIG. 1 , small holes or indentations 2 formed as a result of entrapped air in the concrete poured into wall form used to form the wall are present in various locations on the exposed, exterior surfaces thereof.
The present invention is directed toward creating a cast in place wall having a more uniform texture on its surface, thereby increasing its aesthetic appeal. Referring now to FIGS. 2-5 , there is provided a method of constructing a cast in place concrete wall 10 or other concrete structure having a substantially uniform exterior surface texture. Concrete 12 is a commonly used building material that is comprised of cement, water, aggregates, and admixtures. Admixtures are materials that are added to the concrete 12 to give it certain characteristics that it otherwise would not have, such as accelerating or retarding the stetting time, enhancing frost and sulfate resistance, improving workability, and enhancing finishinability. The aggregates may include sand, pieces of gravel and stone of various size and shape, and recycled materials including concrete.
According to one embodiment of the present invention, a wall form 14 is initially constructed in accordance with the desired shape and size of the wall or outer structure. In the preferred embodiment of the invention, the wall form 14 is constructed out of plywood, however, other materials known by those skilled in the art may also be used. After the wall form is constructed, concrete 12 is poured into the wall form 14 . In order to enhance the strength of the ultimately formed wall or other structure, re-bar may be placed within the wall form 14 before the concrete 12 is poured therein.
Once the concrete 12 is poured into the wall form 14 , it is given a prescribed period of time to cure. During the curing process, the concrete 12 acquires a certain threshold of hardness and strength. Once the concrete 12 at least partially cures, the wall form 14 is removed, thereby exposing the exterior surfaces of the base structure (e.g., a wall, barrier, etc) formed as a result of the curing of the concrete 12 . Thereafter, the exposed surfaces of the base structure formed by the cured concrete 12 are subjected to a procedure which creates a roughened surface texture 16 thereon. The roughened surface texture 16 is created to provide a base for facilitating the adhesion of a finishing mixture 18 thereto, as will be described in more detail below. The roughened surface texture 16 may be created through the use of a number of different surface roughening agents or techniques. For example, the roughened surface texture 16 may be achieved through the use of a form retarder or a spray on retarder. A retarder is the substance that slows the hydration, or hardening, of the concrete 12 . The roughened surface texture 16 may alternatively be created by sandblasting, acid watching, or chemically etching the exposed surfaces of the base structure formed by the cured concrete 12 . Other techniques known by those of skill in the art may also use to facilitate the creation of the roughened surface texture 16 .
Subsequent to the creation of the roughened surface texture upon the base structure formed by the cured concrete 12 , the finishing mixture 18 described above is applied thereto. The finishing mixture 18 may be created by separating large aggregate 20 present in the concrete 12 from the remainder thereof. Such large aggregate 20 may include large pieces of gravel or crushed stone found in the original mixture of concrete 12 poured into the wall form 14 . It is contemplated that by removing the large aggregate 20 from the concrete 12 , the resultant finishing mixture 18 will have a more uniform texture.
In accordance with one embodiment of the present invention, it is contemplated that the finishing mixture 18 may be created from the same mix or batch of the concrete 12 originally poured into the wall form 14 . The use of such original batch may beneficially allow for color consistency between the base structure formed from the cured concrete 12 and the finishing mixture 18 subsequently applied to the exposed exterior surfaces of such base structure having the roughened surface texture 16 formed thereon in the above-described manner. In accordance with another embodiment of the present invention, the finishing mixture 18 may be created from a separate mix of the concrete 12 .
As indicated above, the finishing mixture 18 is applied to the roughened surface texture 16 of the base structure formed by the cured concrete 12 , with the cured finishing mixture 18 ultimately defining the uniformly textured exterior surfaces of a final concrete structure comprising a combination of the base structure and the hardened finishing mixture 18 . The finishing mixture 18 may be applied to the roughened surface texture 16 through the use of a float. In this regard, the finishing mixture 18 is worked into the roughened surface texture 16 until the desired finished surface texture is achieved. At this point, the finishing mixture 18 may be left alone to cure. However, it is contemplated that the finishing mixture 18 may be troweled before curing to achieve a harder texture. In addition, after the finishing mixture 18 fully cures/hardens, it may be acid washed to achieve certain textured features. An exemplary wall 10 formed in accordance with the aforementioned methodology and possessing the smooth, uniformly textured exterior surfaces features highlighted above is shown in FIG. 5 . However, as also indicated above, the methodology of the present invention may also be used to form a plurality of different structures other than the wall 10 shown in FIG. 5 .
The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments. | A method of forming a concrete wall having a substantially uniform exterior surface texture. The method includes the initial step of pouring concrete into a wall form. The concrete is poured from a first mixture and is allowed to cure. After the concrete is cured, the wall form is removed from the resultant concrete base structure. A roughened texture is then created on the base structure. A finishing mixture is then applied to the roughened texture. The finishing mixture may be created by separating the aggregate from a portion of the remaining first mixture. The finishing mixture creates a smooth texture on the exterior surfaces of the initially formed base structure. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to a transmission mechanism in a manual transmission.
In a conventional transmission mechanism, a plurality of shift forks are axially movably supported by a fork shaft fixed on the transmission casing. A shift-and-select lever shaft is mounted on the transmission casing and perpendicularly to the fork shaft. Axial movement of the lever shaft permits selective engagement of the engaging member of the lever shaft with one of the shift forks to effect a select operation, and rotation of the lever shaft permits the movement of the shift fork along the fork shaft to effect a shift operation. However, in this transmission mechanism, when the shift fork is moved along the fork shaft by the rotation of the lever shaft at the shift operation, the shift fork is unable to smoothly move along the fork shaft, thereby deteriorating the feeling of the shift-and-select operation.
SUMMARY OF THE INVENTION
Accordingly, it is a primary object of the present invention to eliminate unsmooth movement of the shift fork along the fork shaft at a shift operation and to provide a transmission mechanism in a manual transmission which may improve the feeling of shift-and-select operation.
According to the present invention, the shift fork which is selected by the axial movement of the shift-and-select lever shaft is effective to move together with the fork shaft at the same speed by the rotation of the lever shaft. For this purpose, the fork shaft is axially movably mounted on the transmission casing and is connected to the lever shaft.
Various general and specific objects, advantages and aspects of the invention will become apparent when reference is made to the following detailed description of the invention considered in conjunction with the related accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a skeltonized diagram of a forward five-speed manual transmission employed in the first preferred embodiment;
FIG. 2 is a sectional front elevation of the transmission mechanism in FIG. 1 and taken along the line II--II in FIG. 3;
FIG. 3 is a sectional side elevation of the transmission mechanism in FIG. 1;
FIG. 4 is an enlarged partially sectional view of the connection between the lever shaft and the fork shaft in FIG. 3;
FIG. 5 is a cross-sectional view taken along the line V--V in FIG. 3; and
FIG. 6 is an enlarged cross-sectional view of the connection between the lever shaft and the fork shaft according to the second preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to FIG. 1 which illustrates a skeltonized diagram of a forward five-speed manual transmission employed in this embodiment, a transmission casing 1 is provided with an input shaft 2 and an output shaft 3 which are rotatably arranged in parallel relation with each other. A first speed gear 4, reverse gear 5 and second speed gear 6 are fixed to the input shaft 2 in sequence from the right-hand side as viewed in FIG. 1. A third speed gear 7, fourth speed gear 8 and fifth speed gear 9 are rotatably born by the input shaft 2 in sequence from the right-hand side as viewed in FIG. 1. A counter gear 10 for the first speed gear 4 and another counter gear 11 for the second speed gear 6 are rotatably born by the output shaft 3. The counter gears 10 and 11 can be at all times in meshing engagement with the first speed gear 4 and the second speed gear 6, respectively. Other counter gears 12 to 14 which can be at all times in meshing engagement with the third, fourth and fifth speed gears 7 to 9 are fixed to the output shaft 3. The counter gears 10 and 11 are designed to rotate together with the output shaft 3 by selective connection of such gears with a sleeve 15a of a first clutch mechanism 15. Similarly, the third speed gear 7 and the fourth speed gear 8 are designed to rotate together with the input shaft 2 by selective connection of such gears with a sleeve 16a of a second clutch mechanism 16. Similarly, the fifth speed gear 9 are designed to rotate together with the input shaft 2 by selective connection of such gear with a sleeve 17a of a third clutch mechanism 17. With this arrangement, the input shaft 2 is driven through a clutch by engine operation and the rotation of the input shaft 2 is transmitted to the output shaft 3 with the speed of rotation varied. A counter reverse gear 18 is provided on the outer circumference of the sleeve 15a of the first clutch mechanism 1. A reverse idler gear 20 is born by the reverse idler shaft 19 which is rotatably supported by the transmission casing 1 so as to rotate together with the shaft 19 and move in its axial direction. When the reverse idler gear 20 is axially moved and is synchronously meshed with the reverse gear 5 and the counter reverse gear 18, the rotation of the input shaft 2 is transmitted to the output shaft 3 under the reversed state. The rotation of the output shaft 3 is transmitted through a driving gear 21 of the shaft 3 to a differential gear 22 and is thereafter transmitted to a right and left driving shafts 23 and 24. FIG. 1 shows a neutral position of the transmission wherein the rotation of the input shaft 2 is not transmitted to the output shaft 3.
FIGS. 2 through 5 show the transmission mechanism adapted for carrying out the operation of transmitting the engine rotation and changing the engine speeds by moving the sleeves 15a to 17a of the clutch mechanisms 15 to 17. The novel feature of the preferred embodiment is the mechanism for operating the first clutch mechanism 15 and the second clutch mechanism 16. As shown in FIGS. 2 and 3, first and second shift forks 25 and 26 are engaged with the sleeve 15a of the first clutch mechanism 15 and the sleeve 16a of the second clutch mechanism 16, respectively in such a manner that both of the sleeves 15a and 16a are permitted to rotate and move in its axial direction. The first and second shift forks 25 and 26 are supported by a first fork shaft 27 and adapted to move in its axial direction. The first fork shaft 27 is axially movably born by the transmission casing 1 in parallel relation with the input shaft 2. The left end portion 28 of the first fork shaft 27 is constructed to be locked by the retainer 29 fixed to the intermediate wall 1a of the transmission casing 1 as viewed in FIG. 2. A third shift fork 30 is engaged with the third sleeve 17a of the third clutch mechanism 17 in such a manner that the sleeve 17a is permitted to rotate and move in its axial direction. The third shift fork 30 is secured by pins 103 to a second fork shaft 31. The second fork shaft 31 is axially movably born by the transmission casing 1 in such a manner that it extends through the intermediate wall 1a of the casing 1. The fork shaft 31 is situated in front of and above the first fork shaft 27 or on the left-hand side of and above the first fork shaft 27 as viewed in FIG. 3, and in parallel relation with the fork shaft 27. A reverse shift arm 32 is axially movably fitted to the right end portions of both the fork shafts 27 and 31. The shift arm 32 is connected to the reverse idler gear 20 in such a manner that the idler gear 20 is permitted to rotate and move in its axial direction. The shift arm 32 is restricted to move rightwardly by a stopper pin 33 inserted through the second fork shaft 31. A one-way pin 36 is accommodated in the shift arm 32 and is engaged with grooves 34 and 35 bored into the first and second fork shafts 27 and 31 which grooves are in opposed relation with each other. With this arrangement, when the second fork shaft 31 is moved leftwardly, and as the result, the shift arm 32 is moved leftwardly together with the second fork shaft 31 by the aid of the stopper pin 33, the one-way pin 36 is disengaged from the groove 34 of the fixed first fork shaft 27 and is moved upwardly to engage the groove 35 of the second fork shaft 31. On the other hand, when the second fork shaft 31 is moved to the original position, the shift arm 32 can be moved together with the second fork shaft 31. When the second fork shaft 31 is moved rightwardly or the first fork shaft 27 is moved rightwardly or leftwardly, the one-way pin 36 is engaged with the groove of the unmoved fork shaft and the reverse shift arm 32 remains at the fixed position.
A first shift head 37 fixedly carries the first fork shaft 27 by pin 104 between the first and second shift forks 25 and 26, and a second shift head 38 fixedly carries the second fork shaft 31 at the near position of the first shift head 37. A head portion 26a integrally formed with the second shift fork 26 is extended at the rear position of the second shift head 38, and a head portion 25a integrally formed with the first shift fork 25 is extended at the rear position of the head portion 26a of the second shift fork 26. The first and second shift heads 37 and 38 and the head portions 25a and 26a are provided with respective recesses A as shown in FIG. 4. The recesses A are arranged in alignment with each other and perpendicularly to each fork shaft 27 and 31 at the neutral position.
A shift-and-select lever shaft 39 is rotatably and axially movably born by the transmission casing 1 in a manner situating above the first and second fork shafts 27 and 31 and perpendicularly to each fork shaft 27 and 31. The lever shaft 39 is designed to axially move through a remote control mechanism (not shown) by the select operation of a shift lever (not shown) and is designed to rotate through the remote contol mechanism by the shift operation of the shift lever. A larger diametrical portion 40 is formed at the central portion of the lever shaft 39, and a first inner lever 41 and a second inner lever 42 are in sequence fixed by pins 101, 102 on the front side of the larger diametrical portion 40 or on the direct left-hand side thereof as viewed in FIG. 3. A front and rear washers 43 and 44 are axially movably inserted around the lever shaft 39 at the front and rear walls 1b and 1c of the transmission casing 1. A front return spring 45 is received between the front washer 43 and the second inner lever 42, and a rear return spring 46 is similarly received between the rear washer 44 and the larger diametrical portion 40. The washers 43 and 44 are prevented from leaving out by a front and rear snap rings 47 and 48 securely fitted around the lever shaft 39, and abut against the front and rear walls 1b and 1c of the casing 1 to maintain the lever shaft 39 at the neutral position. The first inner lever 41 has a projection B extending downwardly therefrom. The projection B is engaged with the recess A of the second shift fork 26 at the neutral position of the lever shaft 39 as shown in FIG. 4. Similarly, the second inner lever 42 has a projection C (FIGS. 2 and 3) extending downwardly therefrom. The projection C is designed to engage the recess A of the first shift head 37 only when the projection B of the first inner lever 41 is engaged with each recess A of the first shift fork 25 or the second shift fork 26. An interlocking plate 49 is fitted to the lever shaft 39 in a manner surrounding the first inner lever 41 while permitting the rotation of the lever shaft 39. A channel 50 is formed on the upper surface of the interlocking plate 49 along the axial length of the lever shaft 39. A locking bolt 51 is threaded into the upper portion of the casing 1 and the lower end of the bolt 51 is engaged with the channel 50 to prevent the rotation of the interlocking plate 49. Front and rear projections 53 and 54 are formed at the lower end of the interlocking plate 49 with the projection B of the first inner lever 41 interposed therebetween as shown in FIG. 4. The projections 53 and 54 are designed to engage the recess A with which the projections B and C of the inner levers 41 and 42 are not engaged. More specifically, when the lever shaft 39 is in the neutral position, the projections 53 and 54 serve to maintain the second shift head 38 and the first shift fork 25 at the fixed position. When the first inner lever 41 is engaged with the first shift fork 25, the projections 53 and 54 serve to maintain the second shift fork 26 and the second shift head 38 at the fixed position. When the first inner lever 41 is engaged with the second shift head 38, the projections 53 and 54 serve to maintain the first shift head 37, the first shift fork 25 and the second shift fork 26 at the fixed position. As shown in FIG. 5, a temporarily fastening mechanism 55 is fitted to the larger diametrical portion 40 of the lever shaft 39. A detent ball 56 accommodated in the mechanism 55 is designed to engage any one of three recesses 49a to 49c formed on the inner circumference of the interlocking plate 49 by a biasing force of the spring 57. With this arrangement, the lever shaft 39 can remain at the selected rotational position.
In operation, to obtain the first speed, the shift-and-select lever shaft 39 at the neutral position is moved rearwardly or rightwardly as viewed in FIG. 3 against the resilient force of the return spring 46 thereby effecting the select operation, and the projection B of the first inner lever 41 is brought into engagement with the recess A of the first shift fork 25. Then, the lever shaft 39 is rotated in the counter-clockwise direction of FIG. 2 thereby effecting the shift operation, and the first shift fork 25 is moved rightwardly to connect the sleeve 15a of the first clutch mechanism 15 with the counter gear 10 for the first speed gear. As is apparent from this arrangement, the shift operation is effected under the condition that the projection C of the second inner lever 42 is engaged with the recess A of the first shift head 37, so that the first shift fork 25 and the first fork shaft 27 are moved at the same speed in association with the rotation of the lever shaft 39. The rightward movement of lever shaft 39 brings the projection 53 of the interlocking plate 49 into engagement with the respective recesses A of the second shift fork 26 and the second shift head 38, and thus the shift fork 26 and shift head 38 are fixed so that the first shift fork 25 and the first fork shaft 27 are axially moved while the second shift fork 26 and the second shift head 38 are fixed.
To obtain the second speed, the lever shaft 39 is rotated in the opposite direction to that in the case of obtaining the first speed, thereby effecting the shift operation, and the first shift fork 25 is moved leftwardly to connect the sleeve 15a with the counter gear 11 for the second speed gear. In the similar manner as the case of obtaining the first speed, the first shift fork 25 and the first fork shaft 27 are moved at the same speed.
To obtain the third speed, the shift-and-select lever shaft 39 at the neutral position is rotated in the couter-clockwise direction as viewed in FIG. 2 to effect the shift operation, and thus the second shift fork 26 with which the projection B of the first inner lever 41 is engaged is moved rightwardly to connect the sleeve 16a of the second clutch mechanism 16 with the third speed gear 7. As is apparent from this arrangement, the shift operation is effected under the condition that the projection C of the second inner lever 42 is engaged with the recess A of the first shift head 37, so that the second shift fork 26 and the first fork shaft 27 are moved at the same speed in association with the rotation of the lever shaft 39. At this point, the projections 53 and 54 of the interlocking plate 49 are brought into engagement with the respective recesses A of the first shift fork 25 and the second shift head 38, and thus the shift fork 25 and the shift head 38 are fixed so as to move the first shift fork 25 relative to the first fork shaft 27.
To obtain the fourth speed, the lever shaft 39 is rotated in the opposite direction to that in the case of obtaining the third speed, thereby effecting the shift operation, and the second shift fork 26 is moved leftwardly to connect the sleeve 16a with the fourth speed gear 8. In the similar manner as the case of obtaining the third speed, the second shift fork 26 and the first fork shaft 27 are moved at the same speed.
To obtain the fifth speed, the shift-and-select lever shaft 39 at the neutral position is moved forwardly against the resilient force of the return spring 45 to effect the select operation, and thus the projection B of the first inner lever 41 is brought into engagement with the recess A of the second shift head 38. Then, the lever shaft 39 is rotated in the counter-clockwise direction as viewed in FIG. 2 to effect the shift operation, and thus the second fork shaft 31 and the third shift fork 30 are moved rightwardly to connect the sleeve 17a of the third clutch mechanism 17 with the fifth speed gear 9. At this point, the first shift head 37, the first shift fork 25 and the second shift fork 26 are fixed with the result that the projections 53 and 54 of the interlocking plate 49 are brought into engagement with the respective recesses A of the first shift head 37, the first shift fork 25 and the second shift fork 26. At this time, the one-way pin 36 is engaged with the groove 34 of the first fork shaft 27 which is fixed with the first shift head 37, and as the result, the reverse shift arm 32 remains at the fixed position.
In order to put each speed gear position into the neutral position, the above mentioned operation should be reversed in order.
To obtain the reverse gear, the lever shaft 39 is rotated in the opposite direction to that in the case of obtaining the fifth speed, thereby effecting the shift operation, and as the result, the second fork shaft 31 is moved leftwardly and the reverse shift arm 32 is moved together with the fork shaft 31 by the aid of the stopper pin 33 to simultaneously mesh the reverse idler gear 20 with the reverse gear 5 and the counter reverse gear 18. To put the reverse gear position into the neutral position, since the one-way pin 36 is engaged with the groove 35 of the second fork shaft 31 during the shift operation for the reverse gear, the reverse shift arm 32 is returned to the neutral position together with the second fork shaft 31.
FIG. 6 shows a second preferred embodiment of this invention in which the first shift head 37 is located between the head portion 25a of the first shift fork 25 and the head portion 26a of the second shift fork 26, and the projection B of the first inner lever 41 is effective to engage the shift head 37 and one of the shift forks 25 and 26. According to this embodiment, the second inner lever 42 employed in the first embodiment may be eliminated.
Having thus described the preferred embodiments of the invention it should be understood that numerous structural modifications and adaptations may be restored to without departing from the spirit of the invention. | Disclosed herein is a transmission mechanism in a manual transmission which may eliminate unsmooth movement of the shift fork along the fork shaft during a shift operation so as to improve the feeling of shift-and-select operation. According to the present invention, the shift fork which is selected by the axial movement of the shift-and-select lever shaft is effective to move together with the fork shaft at substantially same speed by the rotation of the lever shaft. For this purpose, the fork shaft is axially movably mounted on the transmission casing and is connected to the lever shaft. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention generally relates to the field of oil and/or gas exploration and production and more specifically relates to an apparatus and method for maintaining a wellbore.
[0003] 2. Description of the Related Art
[0004] Wells drilled for producing oil and/or gas extend from the surface through a subterranean formation where they intersect a hydrocarbon bearing strata. The wells may include one or more lateral wells that intersect a primary wellbore and extend into the formation away from the primary wellbore. The lateral wellbores typically are formed to produce from a particular hydrocarbon laden zone identified away from the primary wellbore. Additionally, utilizing lateral wellbores enables production from a much larger area while limiting drilling costs to a single primary wellbore.
[0005] From time to time, however, lateral wellbores may require inspection and/or repair. Locating and entering these lateral wellbores can sometimes be difficult due at least in part to the uncertainties inherent in defining the direction of the lateral within the main wellbore. This is especially so when disposing a downhole tool on coiled tubing or wireline. Known devices available for locating a lateral wellbore include mechanical locators provided within the well that can be identified by various means. With reference now to FIG. 1 , an example is shown in a side partial sectional view of a wellbore 2 formed through a subterranean formation 4 . In this example, the wellbore 2 comprises a primary wellbore 3 with lateral wellbores 5 , 6 , 7 intersecting the primary wellbore 3 at various locations along its length.
[0006] A wellbore operations system 10 is shown inserted into the wellbore 2 . The system includes a downhole tool 18 deployed in the primary wellbore 3 on a length of tubing 14 . The tubing 14 is provided from a reel 12 shown threaded through a wellbore tree 16 mounted on the upper end of the wellbore 2 . Further illustrated in FIG. 1 is a whipstock 20 , which is a simple example of an entry device for directing the tool 18 into the lateral wellbore 7 . Also shown in the example of FIG. 1 is water and/or gas 22 emanating from within the lateral wellbore 7 and into the primary wellbore 3 . Addressing unwanted water and/or gas production from a lateral well is one example of downhole operations that can be performed in a lateral well.
SUMMARY OF THE INVENTION
[0007] Disclosed herein is a method of maintaining a wellbore having a primary wellbore and at least one lateral wellbore intersecting the primary wellbore. The wellbore includes a wall along the inner surface of the primary and lateral wellbores. A downhole tool is put into the primary wellbore and forms an annulus between the tool and the wall in the primary wellbore. The tool may include an acoustic transducer used for generating an acoustic signal directed from the tool to the wellbore wall. When the signal reflects from the wellbore wall a reflection signal is formed and is identifiable when reflected from the lateral wellbore. This embodiment of the method may further include receiving the reflection signal, moving the transducer in an axial direction along the wellbore axis, and repeating the steps of generating, receiving, and moving to create a collection of received signals. From the collection of received signals, a reflection from the wall in the lateral wellbore can be identified to estimate where the lateral wellbore intersects with the primary wellbore. The method may further include analyzing fluid in the wellbore for the presence of water and/or gas. Using the sensed water and/or gas and lateral intersection information it can be determined whether the lateral wellbore produces water and/or gas. The tool may further include a bendable sub and the method further may further involve activating the bendable sub so that activating the bendable sub bends a lower portion of the tool into alignment for insertion into a lateral wellbore. The tool may also further include a wellbore seal and the method can further involve inserting the tool into the lateral wellbore and activating the wellbore seal thereby sealing the lateral wellbore from the primary wellbore. The portion of the tool having the wellbore seal can be separated from the remaining portion of the tool and the remaining portion of the tool can be removed from the lateral wellbore thus leaving the portion of the tool having the wellbore seal in the lateral wellbore.
[0008] Also disclosed herein is a downhole tool insertable into a wellbore, the wellbore having a primary wellbore and a lateral wellbore. Included with the tool is a water and/or gas sensor to sense the presence of any water and/or gas flowing from the lateral wellbore and to determine the intersection of the lateral wellbore to the primary. A bendable orienting sub is included with the tool, where the sub bends a lower portion of the tool relative to an upper portion to enter the lateral wellbore. Another feature includable with the tool is a wellbore seal in the lower portion of the tool, which when activated seals the lateral wellbore. The tool further includes a frangible section that releases the lower portion of the tool from the remaining portion to allow the tool to be retrievable while the wellbore seal remains in the lateral wellbore. The tool may optionally include an acoustic signal transmitting and receiving system that emits acoustical signals that are reflected from a wellbore wall to determine the location of a lateral wellbore.
[0009] The present disclosure also includes a wellbore system for investigating a wellbore, where the wellbore has a primary well, a lateral well intersecting the primary well, and a wall on the primary well inner periphery and lateral well inner periphery, the system for estimating where the lateral well intersects the primary well. In one embodiment the system has a sonde disposable into the wellbore, an acoustic array provided with the sonde, the array comprising an acoustic transmitter and a corresponding acoustic receiver, the acoustic transmitter positioned so that when it generates an acoustic signal the acoustic signal is directed away from the sonde in a plurality of lateral directions to an adjacent wellbore wall, wherein the acoustic signal contacts the wellbore wall on one of the primary well inner periphery or lateral well inner periphery and reflects from the wellbore wall to form a reflection signal receivable by the acoustic receiver; and a processor in data communication with the array, the processor configured to analyze data communicated from the array to determine if the reflection signal was by the acoustic signal reflecting from the primary wellbore or the lateral wellbore to thereby estimate the location where the lateral wellbore intersects with the primary wellbore.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] So that the manner in which the features, advantages and objects of the invention, as well as others which will become apparent, may be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof which is illustrated in the appended drawings, which form a part of this specification. It is to be noted, however, that the drawings illustrate only a preferred embodiment of the invention and is therefore not to be considered limiting of the invention's scope as it may admit to other equally effective embodiments.
[0011] FIG. 1 is a side partial sectional view of a prior art method of deploying a downhole tool into a lateral wellbore.
[0012] FIG. 2 is a side partial sectional view of an embodiment of a downhole tool described herein disposed in a wellbore.
[0013] FIGS. 3-5 illustrate the downhole tool in FIG. 2 entering and plugging a lateral wellbore.
[0014] FIG. 6 depicts a downhole tool in accordance with the present disclosure sensing within the wellbore.
[0015] FIG. 7 is an overhead view of the downhole tool of FIG. 6 in a primary wellbore.
[0016] FIG. 8 illustrates in overhead view the downhole tool of FIG. 6 adjacent a lateral wellbore.
DETAILED DESCRIPTION
[0017] Disclosed herein is a method and system for locating lateral well to primary well intersection. Also disclosed herein is a system and method for sensing water and/or gas in wellbore fluid and if the water and/or gas is introduced from a lateral wellbore to a primary wellbore, the system and method identifies the particular lateral wellbore introducing the water and/or gas into the primary wellbore. Further included is a bendable sub for a downhole tool, providing orienting for the tool to enter a lateral wellbore. Also, a seal is included for sealing and blocking a lateral wellbore.
[0018] FIG. 2 illustrates in side partial sectional view an example of a downhole system 30 for use in the wellbore 2 . The system 30 includes a downhole tool 38 shown deployed on tubing 34 within the primary wellbore 3 . The tubing 34 is supplied from a reel 32 and inserted into the wellbore 2 through a production tree 36 that is affixed on the upper end of the wellbore 2 . Optionally, the tool 38 can be lowered on wireline, slickline, or any other lowering and raising means. Downhole tool 38 includes an outer housing 40 having an outer surface defining a sonde. In the embodiment shown, included with the housing 40 are a sensor 42 for sensing water and/or gas, a lateral detector 44 , an orienting sub 42 , a plug or seal section 48 , and a guide shoe 50 .
[0019] The sensor 42 analyzes wellbore fluid adjacent the tool 38 for detecting the presence of water and/or gas 22 in the fluid. Sensor 42 results may be available real time to the surface via tubing 34 or other telemetry means. Water and/or gas downhole can be identified by neutron and/or gradiometer logging tools. Optionally, the results can be stored within the sensor 42 or other areas of the housing 40 and retrieved and analyzed at a later time. In the embodiment of FIG. 2 , the lateral sensor 44 includes an array of acoustic transducers 45 . The acoustic transducers 45 include acoustic transmitters and receivers. Optionally, transducers capable of transmitting and receiving acoustic signals may be included. As will be discussed in more detail below, acoustic signals are generated within the primary wellbore 3 and reflected from the wellbore 2 wall, where receivers within the lateral detector 44 receive the reflected acoustic signal. Signals reflecting from the wellbore wall within the primary wellbore have signatures different from the signatures of signals reflecting from the wellbore wall within the lateral wellbores 5 , 6 , 7 . Identifying the position of the lateral detector 44 when receiving acoustic reflections from the wellbore wall in one of the lateral wellbores 5 , 6 , 7 provides one method of identifying an intersection I between the lateral wellbores 5 , 6 , 7 and the primary wellbore 3 . The wellbore wall can include casing cemented within the borehole.
[0020] The orienting sub 46 bends or deflects at an angle relative to the tool axis A T . Multiple ways of incorporating a bendable sub 46 are known. Examples include asymmetric sliding sleeves, lined coiled tubing, mechanically activated bendable portion, or hydraulically activated sections. The seal or plug section 48 provides a manner of sealing within a wellbore, such as a lateral wellbore; an example includes an outwardly expanding inflatable plug that seals against a wellbore along its inner circumference.
[0021] In one example of use, the tool 38 traverses the primary wellbore 3 , while the lateral detector 44 is activated and generating acoustic signals within the wellbore 2 . Analyzing the signal reflections can locate an intersection I between the primary wellbore 3 and one of the lateral wellbores 5 , 6 , 7 . Optionally, the sensor 42 may be simultaneously sampling the wellbore fluid and identifying water and/or gas 22 content. As noted above, analysis results for water and/or gas content or a lateral intersection, can be stored within the housing 40 or directed to the surface for real time analysis. A processor 41 , such as an information handling unit, can be employed to conduct the analysis, store the analysis results, provide control commands to communicate the analysis to surface, or any other step of control.
[0022] As shown in FIG. 2 , the lateral wellbore 7 includes water and/or gas 22 flowing to the primary wellbore 3 . Correlating the intersection I location with the location where water and/or gas 22 is sensed can identify the lateral wellbore 7 producing the water and/or gas 22 . In one example of use, the tool 38 travels the primary wellbore 3 length to identify lateral to primary wellbore intersections I and water and/or gas presence. The tool 38 travel can be limited to a single in or out sensing/analysis trip, or include additional passes through the wellbore 3 for additional data collection. After identifying the water and/or gas 22 producing lateral wellbore 7 , corrective or remedial action can then be undertaken within the lateral wellbore 7 . Optionally, the sensor 42 can sense the water and/or gas percent in the wellbore fluid in addition to its presence in the wellbore fluid. Based on the mapping step, one or more lateral wellbores can be identified for corrective action.
[0023] FIG. 3 illustrates in side partial sectional view, the tool 38 of FIG. 2 being oriented for insertion into the lateral wellbore 7 . Orienting the tool 38 includes bending the tool 38 so its free end may enter the lateral wellbore 7 . The tool 38 may be bent by activating the orienting sub 46 a into a partial bending configuration, thereby orienting the lower or end of the tool 38 having the guide shoe 50 . The bending step should angle the tool 38 end so the portion below the orienting sub 46 a can enter the lateral wellbore 7 . This requires a bending angle that considers the angle between the primary wellbore 3 and the lateral wellbore 7 and proper azimuthal direction matching the lateral wellbore 7 entrance. Alignment with the proper azimuthal direction can be from a gyroscope (not shown) or real time acoustic monitoring as described herein. It should be pointed out that tool 38 operation is not limited to insertion into a single lateral wellbore 7 , but instead can be operated in any lateral wellbore.
[0024] FIG. 4 illustrates the embodiment of FIG. 3 shown with the tool 38 urged deeper into the lateral wellbore 7 . Also shown in FIG. 4 is the optional plug section 48 activation; activating the plug section 48 deploys a seal 49 extending from the plug section 48 . The seal 49 radially circumscribes the plug section 48 and projects out to the wellbore wall W I in the lateral wellbore 7 . The seal 49 is in sealing engagement with the wellbore wall W I and prevents fluid flow across the plug section 48 . Installing and activating the plug section 48 in the lateral wellbore 7 eliminates water and/or gas 22 contribution from the lateral wellbore 7 into the primary wellbore 3 .
[0025] The plug section 48 is separatable from the tool 38 by a frangible link, either within the plug section 48 or between the plug section 48 and the remaining portion of the tool 38 . Shown in FIG. 5 the plug section 48 is separated from the remaining portion of the tool 38 leaving the plug section 48 and guide shoe 50 in the lateral wellbore 7 . The remaining portion of the tool 38 is retrievable from within the primary wellbore 3 . The frangible section can be a link designed to fail under a pulling shear force. Optionally, an explosive or disintegrating device can be employed for separating the plug section 48 from the tool 38 .
[0026] FIG. 6 is a side schematic view of an embodiment of the tool 38 within the primary wellbore 3 . Signal paths 52 , 54 are provided within the wellbore 2 illustrating an example of a seismic signal direction. Path 52 represents a signal from the acoustic transducers 45 directed to the wellbore wall W P within the primary wellbore 3 . Similarly, path 54 illustrates acoustic signal propagation when directed to the wall W L within the lateral wellbore. In the example of FIG. 6 , the lateral wellbore is lateral wellbore 5 .
[0027] FIG. 7 represents an overhead cutaway view demonstrating an example of signal travel from the sensors 45 and their ensuing reflections from the wellbore wall W P . The sensors 45 are provided at multiple positions around the tool axis A T within the lateral detector 44 . Although the tool 38 is oriented having its axis A T set apart from the primary wellbore axis A W , embodiments exist wherein the axes are substantially aligned. In the embodiment of FIG. 7 , acoustic signals generated within the primary wellbore 3 are represented by arrows 56 shown directed towards the primary wellbore 3 wall W P . The acoustic signals 56 reflect from the wall W P and form a reflected signal 58 . In the embodiment shown, the acoustic signals 56 are oriented away from the tool 38 in a direction perpendicular to the axis A T . Consequently, the reflected signal 58 propagates in a direction substantially along the path of the acoustic signal 58 and towards the tool 38 . However, other embodiments are available, wherein the acoustic path 56 extends along a path generally oblique to one of the tool axis A T , the well axis A W , or both.
[0028] By estimating the fluid properties within the well 2 , the sound speed within the wellbore fluid can be estimated, thereby providing an estimated value of distance between each of the sensors 45 and the wellbore wall W P . These distances can be calculated within the processor 41 optionally provided within the tool 38 , stored within the tool 38 , or communicated to the surface for real time analysis. Subsequent cycles of acoustic signal generation and detection can be performed at different depths within the wellbore 2 . This can be an incremental or a continuous fashion. It is believed it is well within the capabilities skilled in the art to devise a suitable method of disposing the tool 38 within the wellbore while making acoustic estimations within the wellbore. Using the data collected the wellbore dimensions adjacent the tool 38 can be estimated.
[0029] FIG. 8 illustrates an overhead schematic view of the tool 38 in the wellbore, wherein the lateral detector 44 is disposed adjacent the intersection I to form the acoustic path 54 . As shown, generated signals 56 directed towards the wellbore wall W P and the primary wellbore will generate reflected signals 58 similar to those of FIG. 7 , both in direction and arrival time to the sensor 45 . However, generated signals 56 a, 56 b directed towards the intersection, are shown extending past the line representing the primary wellbore wall W P into the wellbore wall lining the lateral wellbore 5 . The reflected signals 58 a, 58 b produced by reflecting signals 56 a, 56 b on the wellbore wall W L within the lateral wellbore 5 will, according to Snell's law, have a primary component directed at an angle with respect to the sensor 45 that generated the signals 56 a, 56 b. Accordingly, magnitude and travel time detected for the reflected signals 58 a, 58 b from the lateral wellbore wall W L will differ from the travel time and signal magnitude a signal reflected from the primary wellbore wall W P . As such, the location of the intersection I between the primary wellbore 3 and any of the lateral wellbores may be identified through analyzing reflected acoustic signal data.
[0030] Optionally, a database of reflected signal data can be created empirically, through actual recording when disposing a tool downhole, as well as during the particular operation when attempting to identify a wellbore lateral. By correlating the response of acoustics within the intersection area with the measured depth of the tool 38 can provide an estimated location of the intersection I within the wellbore 2 .
[0031] Alternative embodiments include a single sensor 45 on the tool 38 , wherein the tool may be rotated during use. Optionally, in a pair of transducers, such as an acoustic transmitter and an acoustic receiver may be included on a tool at a single location. Although sensors 45 are shown in six locations around the tool 38 , multiple other embodiments exist having less or more than six locations for sensors on a tool 38 .
[0032] In an alternative embodiment, the downhole tool 38 may include a lateral detector 44 . In other embodiments one or more additional features described above, in any combination, can be included with the lateral detector 44 , such as the processor 41 , the sensor 42 , the orienting sub 46 , the plug section 48 , and the guide shoe 50 . Embodiments of the tool 38 may alternatively include wellbore exploration devices, perforating devices, and fracturing systems.
[0033] While the invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention. | A tool used for treating and/or maintaining a wellbore that includes acoustic transducers for locating a lateral wellbore that intersects a primary wellbore. The tool includes a sensor to sense water and/or gas, and if the water and/or gas enters the primary wellbore from a lateral wellbore, the lateral to primary intersection can be identified by correlating information from the sensor and acoustic transducers. If needed, the tool can be used to plug the water and/or gas supplying lateral wellbore. The tool may include a bendable sub portion for orienting a portion of the tool for insertion into the lateral wellbore and a plug section for plugging the lateral wellbore after insertion therein. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending International Application No. PCT/DE00/04564, filed Dec. 20, 2000, which designated the United States and was not published in English.
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a testing device for a semiconductor component including at least one first contact, with at least one second contact for producing an electrical connection to the first contact.
Testing devices serve for testing semiconductor components for serviceability following their fabrication. The semiconductor component—the specimen—which includes first contacts —is placed on the testing device with the first contacts in contact with second contacts of the testing device to produce an electrical connection. Some of the second contacts are charged with predetermined potentials. The signals that are sent by the semiconductor component are then tapped at other second contacts and fed to an evaluation.
The construction of the second contacts of the testing device is described in the article “Get grip on RP components” ( Test and Measurement World; May 1994:73ff). FIG. 1 of this article is a cutout of a common testing device. The second contacts, i.e., the contacts of the testing device, are connected to the testing device to be rotatable about a horizontal elastomer axis. The semiconductor component is placed on the testing device such that the first contacts (of the semiconductor component) become connected to the second contacts (of the testing device). To produce a low-impedance connection between the first and second contacts, a stamp (a contact pressure block) exerts pressure on the first contact. As a consequence of the stamp pressure, the second contacts of the testing device, which are movable, are shifted slightly out of neutral position.
Due to the slight relative movement of the second contact in relation to the first contact, the second contacts become worn over time. Such wearing roughens the surfaces of the second contacts. Thus, the contact resistance between the first and second contacts changes over time. Given the variance over time, the contact resistance can falsify the test results.
An additional disadvantage of spring-mounted second contacts is that the capacity between the first contact and the track (signal trace) changes as the spacing varies. Such variation of the parasitic capacities can also lead to falsification of the measuring results.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a testing device for a semiconductor component that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and that avoids the above described disadvantages.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a semiconductor component testing device, including at least one immobile second contact to be electrically connected to at least one first contact of a semiconductor component, the at least one second contact being immobile relative to the testing device.
Accordingly, it is inventively provided that the second contact be immobile in relation to the testing device. As a result, only small parasitic capacities arise because the spacing between a first contact of the semiconductor component and a metal in the testing device cannot vary. Furthermore, because there is no relative movement between the first contact and the second contact, hardly any abrasion events occur at the second contacts of the testing device.
In accordance with another feature of the invention, the second contacts have the shape of a lamina and/or are lamina-shaped. This means that the second contacts have a flat surface. The dimensions of the lamina are preferably selected so as to be larger than the first contacts of the semiconductor component. Such a configuration makes possible a more secure contact. On the other hand, by virtue of its flat main surface, the lamina can be effectively connected to a track of the testing device. The connection between the lamina and the track can be realized by soldering.
The second contacts advantageously are of a hard, highly conductive material. The harder the material, the less wear that occurs over time. In a preferred variant, the second contacts are of beryllium copper. The second contacts could also conceivably be made of platinum. Beryllium copper has the characteristic that it exhibits only a small mechanical expansion given temperature fluctuations. Because the expansion is small, very small parasitic electrical components emerge, which exert practically no influence on the characteristics of the semiconductor component during the test procedure. The small parasitic electrical components can represent the above mentioned parallel capacity or a series inductivity.
To achieve an optimally small contact resistance and an insensitivity to deposits or contaminants, it is advantageous to construct the surface of the second contacts so that they include peaks. The peaks can have the shape of a triangle or polygon or any other shape. If possible, the spacing of the peak of the surface of the second contact should be no greater than the width of the peak on the surface of the second contacts. Such a configuration guarantees that the peak cannot break even under large mechanical loads. The peak is disposed on the surface of the second contact that faces the first contact of the semiconductor component. For testing, the first contacts of the semiconductor component are separately pressed onto the peaks of the second contacts by a stamp. It goes without saying that the stamp for exerting the pressure is of an insulating material.
With the objects of the invention in view, there is also provided a semiconductor component testing device, including a testing base and at least one second contact to be electrically connected to at least one first contact of a semiconductor component, the at least one second contact connected to and being immobile relative to the testing base.
With the objects of the invention in view, there is also provided a semiconductor component testing device, including a carrier with a surface, an insulating substrate disposed on the surface, and at least one contact to be electrically connected to at least one component contact of the semiconductor component, the at least one contact connected to the insulating substrate, the at least one contact being immobile relative to the insulating substrate and to the carrier.
In case high temperatures arise in the semiconductor component during testing, it can be advantageous to provide a heat sink in the testing device, which is then connected to the semiconductor component.
With the objects of the invention in view, there is also provided a semiconductor component testing device, including a carrier with a surface, an insulating substrate disposed on the surface, a heat sink disposed on the surface for conveying heat from a semiconductor component to the carrier, and at least one contact to be electrically connected to at least one component contact of the semiconductor component, the at least one contact connected to the insulating substrate, the at least one contact being immobile relative to the insulating substrate and to the carrier.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a testing device for a semiconductor component, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary cross-section of an embodiment of the testing device according to the invention; and
FIG. 2 is an enlarged, fragmentary cross-section of first and second contacts of FIG. 1 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the Figures of the drawings in detail and first, particularly to FIG. 1 thereof, there is shown an exemplifying embodiment of the inventive testing device 8 . The testing device 8 includes an insulating substrate 4 , on which tracks 10 have been installed. The substrate 4 lies on a carrier 5 , which is connected to a semiconductor component 1 by way of a heat sink 6 and which produces a ground-related, highly thermally conductive contact to the semiconductor component 1 . Each track 10 is connected to a second contact 3 . The second contact 3 is constructed in the shape of a lamina, preferably, of beryllium copper. The second contact 3 is permanently connected to the track 10 , for instance, by soldering.
The second contact 3 includes a peak 7 (see FIG. 2 ) that is connected to a first contact 2 of a semiconductor component. The first contacts 2 are pressed to the second contacts 3 by a pressure. The arrows A are meant to indicate such pressure. The pressuring tool is not represented in FIG. 1 . The pressuring tool provides that the peaks 7 of the second contacts 3 press lightly into the first contacts 2 . As such, low contact resistance can be produced.
FIG. 2 represents an enlarged view of the mechanical connection between the first contact 2 and the second contact 3 with its peak 7 . The second contact 2 is in contact with the peak 7 . With the aid of the non-illustrated pressuring tool, the peak 7 presses lightly into the first contact 2 .
In the present exemplifying embodiment, the peak 7 is constructed in the shape of a triangle. The peak 7 could also be constructed in the shape of a polygon or any other shape. It is advantageous when the spacing between the peak 7 and the surface 9 of a second contact 3 is smaller than the spacing B. The peak 7 can be produced by milling the lamina, which has a cuboid cross-section, from the surface 9 . The second contact 3 preferably has a thickness D between 200 and 300 μm. Such a configuration guarantees a high durability of the second contact.
FIG. 1 represents a semiconductor component 1 in which the first contacts 2 are situated adjacent its housing. It would also be imaginable to apply the inventive testing device to semiconductor components wherein the first contacts are situated beneath the housing. It goes without saying that the second contacts 3 must be respectively adapted to the layout of the first contacts 2 of the semiconductor component. For semiconductor components in which the first contacts are situated below the housing, a tool would have to exert the pressure directly onto the housing to produce a low-resistance connection between the first and second contacts.
Compared to prior art testing devices that utilize spring contacts, substantially smaller parasitic electrical components emerge in the testing configuration according to the invention due to the immobility of the second contacts relative to the testing device. The mechanical loads on the second contacts, thus, being slight, the long-term durability of the second contacts of the testing device is guaranteed. | A testing device for a semiconductor component including at least one first contact. The testing device contains at least one second contact for producing an electrical connection to the first contact. The second contact is immobile relative to the testing device. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to a lubricating oil base oil having characteristics of low volatility and excellent low-temperature fluidity and capable of providing long-lasting lubrication property in a wide temperature range from low temperature to high temperature, and a lubricating oil composition using the same.
BACKGROUND ART
[0002] A lubricating oil base oil is required to exert its performance stably for a long period of time, i.e., to have low volatility, excellent heat and oxidation stability and low-temperature startability (low-temperature fluidity), and a high viscosity index (wide range). In particular, it is not too much to say that a lubricating oil base oil having characteristics of low viscosity and low volatility is an ultimate aim.
[0003] Along with improvements in performance of audio-visual and office automation equipment, a small spindle motor used in a rotating part in the equipment has been strongly required to be refined so as to achieve speed-up and electrical power saving. Therefore, a bearing used in a rotation-supporting part has been constantly required to achieve low torque. Meanwhile, particularly recently, the bearing has been required to have performance applicable to various environments (temperatures) in consideration of use as a mobile device. As a factor having an effect on the torque of the bearing, there are given a bearing clearance and a shaft diameter. In particular, the viscosity of a lubricating oil in a low-temperature environment is a major factor.
[0004] In general, a lubricating oil having a lower viscosity tends to easily evaporate. When an amount of the lubricating oil decreases due to evaporation, the bearing is judged to come to the end of its life because of an inappropriate oil film pressure and significantly lowered rotation accuracy. Therefore, an evaporation characteristic of the lubricating oil is an important characteristic which affects durability of the bearing. Accordingly, in lubrication of a sliding bearing such as a fluid dynamic pressure bearing, an oil-impregnated porous bearing, or a dynamic pressure-type oil-impregnated porous bearing, it is necessary to select a lubricating oil which has a low viscosity, does not cause an increase in the viscosity even in a low temperature range, and has a relatively excellent evaporation characteristic. In many cases, an ester-based lubricating oil is used.
[0005] Like other lubricating oils, an ester oil tends to have a lower evaporation characteristic as the viscosity becomes lower. Therefore, to reduce the torque of the bearing, even when an ester oil having a lower viscosity than that of a conventional one is selected, the evaporation characteristic is impaired, resulting in a reduction in durability of the bearing. In addition, even when the oil has a low viscosity at ordinary temperature, a rapid increase in torque or stopping of devices may occur when the viscosity increases drastically or the fluidity is lost in a low temperature range.
[0006] Particularly, in recent years, hard disks are often installed in home electronics and may be used at low temperature in many cases. Therefore, in order to ensure stable driving, a low viscosity in a low temperature range has been strongly required. Many lubricating oil base oils have been proposed to satisfy such properties. However, in the present circumstances, the oils do not satisfy the low viscosity and low volatility which are ultimate aims although the oils satisfy the properties to some extent.
[0007] The low viscosity and low volatility contradict each other. For example, when the viscosity is reduced without changing its structure, the molecular weight decreases, naturally resulting in an increase in volatility. As means for solving such defects, an ester-based base oil having a low viscosity and relatively excellent evaporation property is used.
[0008] Patent Literature 1 discloses a lubricating oil composition including, as a base oil, a diester obtained from a linear divalent alcohol having 6 to 12 carbon atoms and a branched saturated monovalent fatty acid having 6 to 12 carbon atoms.
[0009] However, according to the conventional technology, a lubricating oil having low-viscosity property can be obtained by appropriately selecting an alcohol and a fatty acid. However, in the case of a diester having a viscosity at 40° C. of 10 mm 2 /s or less, the evaporation amount becomes larger as its molecular weight becomes lower. Further, the evaporation occurs concurrently owing to a uniform molecular weight, and hence the durability may drastically deteriorate from a certain condition. This is because many of esters have symmetrical chemical structures. That is, the limiting point is clear because of a single composition, and the evaporation may cause sudden stopping of the motor. This is probably because, in a combination of 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol with 2-ethylhexanoic acid and 3,3,5-trimethylpentanoic acid, which is considered by the above-mentioned conventional technology to be particularly suitable, the viscosity index is small because a ratio of components having branched carbon structures is large based on the molecular weight, and the viscosity becomes particularly high at low temperature, resulting in an adverse effect on driving property of the motor under a usual environment. In addition, this is probably because, as the ratio of the branched structures in the diesters becomes larger, the evaporativity becomes larger.
[0010] Patent Literature 2 discloses a lubricating oil composition which contains: as a major component, an ester synthesized from a monovalent alcohol having 8 carbon atoms and a divalent carboxylic acid having 6 carbon atoms; and, at a concentration of 1 to 5 wt, a diester which is different from the major component, has a kinetic viscosity at 40° C. of 10 mm 2 /s or more, and has a total of 23 to 28 carbon atoms in its molecule, and a fluid bearing unit using the lubricating oil composition.
[0011] Patent Literature 3 describes a lubricating oil base oil containing, as a major component, a diester compound or a triester compound synthesized from a divalent or trivalent carboxylic acid having 9 or less carbon atoms and a monovalent glycol ether such as an alkylene glycol monoalkyl ether having 3 to 25 carbon atoms.
[0012] However, the lubricating oils or lubricating oil base oils described in the literatures do not fully satisfy the requirements of low viscosity and low volatility.
CITATION LIST
Patent Literature
[0000]
[PTL 1] JP 2008-69234 A
[PTL 2] JP 2007-39496 A
[PTL 3] WO 2007/116725 A1
SUMMARY OF INVENTION
[0016] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a lubricating oil base oil having characteristics of low volatility and excellent low-temperature fluidity and capable of providing long-lasting lubrication property in a wide temperature range from low temperature to high temperature, and a lubricating oil composition using the same.
[0017] The present invention relates to a lubricating oil base oil, including one or more kinds of diesters selected from the group consisting of diesters represented by the following formulae (1), (2), and (3), in which the total number of carbon atoms involved in methyl groups and ethyl groups present as branched structures in the diesters represented by the formulae (1), (2), and (3) is 11% or less with respect to the number of all carbon atoms, and the ratio (molar ratio) of the diesters represented by the formulae (1), (2), and (3) falls within a range of (1):(2):(3)=45 to 100:0 to 45:0 to 12:
[0000]
[0000] where C 3 H 7 and C 4 H 9 represent n-C 3 H 7 and n-C 4 H 9 , respectively.
[0018] In the lubricating oil base oil, it is preferred that the total of the diesters represented by the formulae (1), (2), and (3) be 70 wt % or more with respect to the lubricating oil base oil.
[0019] It is preferred that the lubricating oil base oil include, at a concentration of 30 wt % or less, a low-viscosity oil which includes a polyol ester having a kinetic viscosity at 40° C. of less than 9 mm 2 /s, having a viscosity index of 100 or more, and having a neopentyl glycol skeleton. It is more preferred that the low-viscosity oil include a polyol ester obtained from caprylic acid or capric acid and neopentyl glycol.
[0020] The present invention also relates to a lubricating oil composition which is obtained using the lubricating oil base oil.
DESCRIPTION OF EMBODIMENTS
[0021] Embodiments of the present invention are described below.
[0022] A lubricating oil base oil of the present invention contains one or more kinds of diesters selected from the group consisting of diesters represented by the formulae (1), (2), and (3), and the ratio (molar ratio) of the diesters represented by the formulae (1), (2), and (3) falls within a range of (1):(2):(3)=45 to 100:0 to 45:0 to 12. Further, in the diesters represented by the formulae (1), (2), and (3), the total number of carbon atoms involved in methyl groups and ethyl groups present as branched structures is 11% or less with respect to the number of all carbon atoms. The lubricating oil base oil has no excessive branched chains, and hence has a high viscosity index and a particularly low viscosity in a low temperature range. In addition, the oil is excellent in low evaporativity.
[0023] The lubricating oil base oil of the present invention is obtained by an esterification reaction of 1,12-dodecanediol with one kind or two kinds of acids selected from 2-methylpentanoic acid and 2-ethylhexanoic acid. 2-Methylpentanoic acid is essential, but 2-ethylhexanoic acid is optionally used.
[0024] When only 2-methylpentanoic acid is used as an acid, a diester represented by the formula (1) is generated. When only 2-ethylhexanoic acid is used, a diester represented by the formula (3) is generated. When both 2-methylpentanoic acid and 2-ethylhexanoic acid are used as acids, a diester including diesters represented by the formulae (1) to (3) is generated as a mixture. In this case, the ratio of the diesters varies depending on the ratio of amounts of 2-methylpentanoic acid and 2-ethylhexanoic acid used. It should be noted that when the diester represented by the formula (1) and the diester represented by the formula (3) were separately produced and mixed, a diester including the diesters represented by the formulae (1) and (3) is obtained as a mixture.
[0025] In the lubricating oil base oil of the present invention, when the ratio of the diesters represented by the formulae (1), (2), and (3) is adjusted to a certain range, the viscosity at low temperature, evaporativity, and low-temperature fluidity can be improved. The ratio of the diesters represented by the formulae (1), (2), and (3), represented by (1):(2):(3), falls within a range of 45 to 100:0 to 45:0 to 12, preferably a range of 40 to 85:10 to 45:1 to 15.
[0026] However, in the lubricating oil base oil of the present invention, it is necessary to adjust the ratio of the number of branched carbon atoms (hereinafter, referred to as “branched carbon atom ratio”) to a certain level or less. Herein, the number of branched carbon atoms is calculated from the total number of carbon atoms in the methyl groups and ethyl groups represented as side chains in the formulae (1), (2), and (3). Herein, the term “side chain” refers to an alkyl group to be substituted for a major chain including a linear carbon chain which links C 3 H 7 or C 4 H 9 moieties located at both ends in the formulae (1), (2), and (3). For example, the formula (1) is understood to represent a diester having two methyl groups in side chains and having a total of 24 carbon atoms, and in this case, the branched carbon atom ratio is 2/24. On the other hand, the formula (3) is understood to represent a diester having two ethyl groups in side chains and having a total of 28 carbon atoms, and in this case, the branched carbon atom ratio is 4/28. The formula (2) is understood to represent a diester having one methyl group and one ethyl group in side chains and having a total of 26 carbon atoms, and in this case, the branched carbon atom ratio is 3/28. In the case of a mixture of the diesters, the branched carbon atom ratio is calculated as a weighted average of the values. Therefore, the amount of the diester represented by the formula (3) is limited by this.
[0027] In the lubricating oil base oil of the present invention, the content of the diesters is preferably 50 wt % or more with respect to the base oil. When the content is 70 wt or more, the low viscosity and low evaporativity of the lubricating oil at low temperature can be improved sufficiently. As a method of mixing another base oil component by synthesis, there are given a method involving mixing a diol other than 1,12-dodecanediol and esterifying the components and a method involving mixing an acid other than 2-methylpentanoic acid and 2-ethylhexanoic acid and esterifying the components. As a method of mixing another base oil component by mixing, there is given a method of mixing base oil components with an existing base oil such as an ester or a polyalphaolefin.
[0028] In particular, a lubricating oil base oil containing a low-viscosity oil which is a polyol ester having a kinetic viscosity at 40° C. of less than 9 mm 2 /s, having a viscosity index of 100 or more, and having a neopentyl glycol skeleton has an advantage in that low-temperature fluidity can further be given while maintaining the low viscosity and low evaporativity of the lubricating oil at low temperature. The low-viscosity oil component is preferably an esterification product of neopentyl glycol and capric acid or caprylic acid. Further, in the case where the base oil contains the low-viscosity oil, the content is preferably 30 wt % or less with respect to the base oil.
[0029] The diester represented by the formula (1), (2), or (3) is prepared from the above-mentioned acid component and diol component in accordance with a conventional method preferably in an inert gas (such as nitrogen) atmosphere in the presence or absence of an esterification catalyst by stirring with heating or the like to diesterify the components. Specifically, a method of synthesizing a diester by esterification at high temperature while water generated by a condensation reaction is removed may be employed. The reaction may be performed without a catalyst or using a catalyst such as sulfuric acid, para-toluenesulfonic acid, or a tetrakis(alkoxy)titanate. The reaction may be performed further using an anhydrous solvent such as toluene, ethyl benzene, or xylene. In the esterification reaction, the acid component is used in an amount of, for example, 2.0 mol or more, preferably 2.01 to 4.5 mol with respect to 1 mol of the diol component.
[0030] The lubricating oil base oil of the present invention is used as a base oil for lubricating oil compositions such as a liquid lubricating oil and grease. The lubricating oil composition of the present invention is prepared by using the base oil blending the base oil with a component for improving the performance of the lubricating oil composition in the base oil. Examples of the component include a known additive or thickener such as an antioxidant, an oiliness improver, a wear inhibitor, an extreme pressure agent, a metal deactivator, an anti-corrosive, a viscosity index improver, a pour point depressant, or an antifoamer. One or more kinds of such additives may be appropriately blended. Such additives are added at a concentration of preferably 0.01 to 10 wt %, more preferably 0.03 to 5 wt % with respect to the lubricating oil base oil.
[0031] In the case where the lubricating oil composition of the present invention is a grease, a thickener used in the composition is not particularly limited, and a thickener used in a general grease may appropriately be used. Examples thereof include a metal soap, a complexed soap, urea, an organic bentonite, and silica. In general, the content of the thickener in the grease is suitably 3 to 30 wt %. Further, one kind or two or more kinds of additives generally blended, such as an antioxidant, an extreme pressure agent, an anti-corrosive, a metal corrosion inhibitor, an oiliness improver, a viscosity index improver, a pour point depressant, or an adhesion improver may appropriately be blended in the grease. Such additives are usually added at a concentration of preferably 0.01 to 10 wt %, more preferably 0.03 to 5 wt % with respect to a grease base oil.
[0032] The lubricating oil composition including the lubricating oil base oil of the present invention can be used in: industrial lubricants such as a hydraulic oil, a gear oil, a spindle oil, and a bearing oil; and various applications such as a dynamic pressure bearing oil, an oil-impregnated sintered bearing oil, a hinge oil, a sewing machine oil, and a sliding surface oil. The composition as a grease is applicable to various lubricating parts such as bearing parts (ball, roller, and needle), sliding parts, and gear parts. In particular, the composition is advantageously applicable to a fluid bearing unit, a fluid dynamic pressure bearing unit, an oil-impregnated porous bearing unit, and a spindle motor equipped with such units.
[0033] Examples of preferred use of the lubricating oil composition of the present invention are shown below.
[0034] 1) Fluid bearing unit: a bearing unit including a bearing part which supports a rotating shaft by an oil film pressure of a lubricating oil present in a gap between an axis outer periphery and a sleeve inner periphery, in which the lubricating oil composition of the present invention is used as a lubricant. 2) Fluid dynamic pressure bearing unit: a bearing unit including a dynamic pressure generating groove in any of the axis outer periphery and sleeve inner periphery, in which the lubricating oil composition of the present invention is used as a lubricant. 3) Oil-impregnated porous bearing unit: a unit having an oil-impregnated porous bearing impregnated with the lubricating oil composition of the present invention. 4) Oil-impregnated porous bearing: a bearing impregnated with the lubricating oil composition of the present invention. Preferred examples of the oil-impregnated porous bearing include a dynamic pressure-type oil-impregnated porous bearing. 5) Spindle motor: a spindle motor equipped with the above-mentioned bearing units.
EXAMPLES
[0035] Hereinafter, the present invention is specifically described by way of examples. However, the present invention is by no means limited to the following examples.
Example 1
[0036] 80.93 g of 1,12-dodecanediol and 185.81 g of 2-methylpentanoic acid were added to a reaction device including a 500-cc four-necked flask, a heating device, a stirring device, a thermometer, a nitrogen vent tube, a nitrogen line, a Dean-Stark tube, a cooling tube, and a cooling line, and subjected to a reaction using tetrakis (IV) (2-ethyl-1-hexyloxy)titanate as a catalyst in a nitrogen atmosphere at 170° C. for 48 hours with stirring until full esterification was achieved. Most of carboxylic acids which remained in the reaction oil were distilled off at 10 Torr and 170° C., and the catalyst was deactivated. The acids which remained in the esters were neutralized, and unreacted compounds and impurities in the esters were removed by an adsorption treatment, to thereby obtain a diester (d1). The composition of the diester was determined by a molar ratio calculated from an area ratio determined by gas chromatography. The diester represented by the formula (1) was found to occupy 99.3 wt % of the whole.
Example 2
[0037] A diester (d2) was obtained by esterification using 80.93 g of 1,12-dodecanediol, 91.97 g of 2-methylpentanoic acid, and 12.69 g of 2-ethylhexanoic acid in the same manner as in Example 1. The diester (d2) was a mixture of the diesters represented by the formulae (1), (2), and (3), and the ratio (molar ratio) of diesters represented by the formulae (1), (2), and (3) was found to be (1):(2):(3)=81.1:17.9:1.0. The diesters were found to occupy 99.0 wt % of the whole.
Example 3
[0038] A diester (d3) was obtained using 80.93 g of 1,12-dodecanediol, 89.39 g of 2-methylpentanoic acid, and 27.75 g of 2-ethylhexanoic acid in the same manner as in Example 2. The diester (d3) was found to contain the diesters at a ratio of (1):(2):(3)=63.2:32.6:4.1. The diesters were found to occupy 99.3 wt % of the whole.
Example 4
[0039] A diester (d4) was obtained using 80.93 g of 1,12-dodecanediol, 78.06 g of 2-methylpentanoic acid, and 41.54 g of 2-ethylhexanoic acid in the same manner as in Example 2. The diester (d4) was found to contain the diesters at a ratio of (1):(2):(3)=57.8:36.5:5.7. The diesters were found to occupy 99.3 wt % of the whole.
Example 5
[0040] A diester (d5) was obtained using 80.93 g of 1,12-dodecanediol, 75.00 g of 2-methylpentanoic acid, and 44.50 g of 2-ethylhexanoic acid in the same manner as in Example 2. The diester (d5) was found to contain the diesters at a ratio of (1):(2):(3)=53.9:39.1:7.0. The diesters were found to occupy 99.3 wt % of the whole.
Example 6
[0041] A diester (d6) was obtained using 80.93 g of 1,12-dodecanediol, 71.70 g of 2-methylpentanoic acid, and 50.54 g of 2-ethylhexanoic acid in the same manner as in Example 2. The diester (d6) was found to contain the diesters at a ratio of (1):(2):(3)=45.0:44.1:10.8. The diesters were found to occupy 99.3 wt % of the whole.
Example 7
[0042] A diester (d7) was obtained by mixing 90 wt % of the diester (d4) synthesized in Example 4 with 10 wt % of a diester of neopentyl glycol (H2962 manufactured by Hatco: having a branched methyl group and having a branched carbon atom ratio in the ester of 8.9%).
Example 8
[0043] A diester (d8) was obtained by mixing 72.5 wt % of the diester (d4) synthesized in Example 4 with 27.5 wt % of H2962.
Comparative Example 1
[0044] A diester (d9) was obtained by esterification using 1,8-octanediol and 2-ethylhexanoic acid as raw materials in the same manner as in Example 1.
Comparative Example 2
[0045] A diester (d10) was obtained by esterification using 2,4-diethyl-1,5-pentanediol and caprylic acid as raw materials in the same manner as in Example 1.
[0046] Table 1 shows compositions and various physical properties of the diesters (d1) to (d10) obtained in Examples and Comparative Examples.
[0000]
TABLE 1
Branched
(1) +
carbon
Kinetic
Pour
Acid
(2) +
atom
viscosity
point
number
Evaporation
(3) %
ratio %
mm 2 /s
° C.
mgKOH/g
loss %
Exam-
ple
1
99.3
8.3
66.4
−32.5
0.02
2.50
2
99.0
9.0
70.3
−37.5
0.02
2.20
3
99.3
9.6
80.5
−42.5
0.02
2.12
4
99.3
9.8
82.9
<−45
0.01
1.89
5
99.3
10.0
84.8
<−45
0.02
1.65
6
99.3
10.4
87.1
<−45
0.03
1.50
7
89.4
9.7
81.2
<−45
0.02
2.29
8
72.0
9.6
76.8
<−45
0.02
2.50
Comp.
Exam-
ple
1
—
16.7
93.8
<−45
0.03
4.20
2
—
16.0
95.3
<−45
0.03
2.89
[0047] In Table 1, the term “kinetic viscosity” refers to a value determined at −10° C. The term “evaporation loss” refers to a weight loss (%) determined after a diester has been kept at 120° C. for 8 hours in a thermobalance in a nitrogen atmosphere.
[0048] Additive and abbreviation thereof
[0000] L57: alkyldiphenylamine (IRGANOX L57 manufactured by BASF, antioxidant)
IR39: benzotriazole derivative (IRGAMET 39 manufactured by BASF, metal deactivator)
OAS1200: succinimide (OAS1200 manufactured by Chevron Chemical Company, ash-free dispersant)
Examples 11 to 14
[0049] Lubricating oil compositions were prepared by using as base oils the diesters (d1), (d4), (d7), and (d8) obtained in Examples 1, 4, 7, and 8, respectively, and blending the diesters with 0.5 wt % of 157, 0.03 wt % of IR39, and 1.5 wt % of OAS1200.
Comparative Example 3
[0050] A lubricating oil composition was prepared by using the diester (d9) obtained in Comparative Example 1 as a base oil, and blending the diester with 0.5 wt % of 157, 0.03 wt % of IR39, and 1.5 wt % of OAS1200.
[0051] Each of the above-mentioned lubricating oil compositions were subjected to an evaporation test and evaluated on its rotating viscosity at −10° C. to simulate bearing torque when used in an oil-impregnated bearing.
[0052] The evaporation test was carried out under conditions of 100° C. and 6,000 hours. It should be noted that the evaporation test was carried out using LABORAN screw tubes #3 (volume: 9 ml) including 2 g of samples. The number n of the samples was defined as 2, and the average was determined as an evaporation loss. An evaporation loss of 0.5% or less, determined under conditions of 100° C. and 6,000 hours, was defined as a standard value. According to findings, a lubricating oil having an evaporation loss of 0.5% or more tends to have an exponentially increased evaporation loss after a lapse of 6,000 hours.
[0053] The rotation property which causes a problem when the lubricating oil composition is used in an oil-impregnated bearing is low-temperature torque. In particular, when the rotating torque at −10° C. is large, the burden on a buttery increases. Therefore, the bearing torque in an actual machine was simulated by measuring the rotating viscosity at −10° C. It should be noted that a motor manufacturer requires use of a sample having a rotating viscosity at −10° C. of 100 mPa·s or less. Therefore, the standard value was defined as 100 mPa·s or less.
[0054] As a measurement device, SVM-3000 manufactured by Anton Paar was used.
[0000]
TABLE 2
Kinetic
Acid
viscosity
Pour point
number
Evaporation
Example
Base oil
mm 2 /s
° C.
mgKOH/g
loss %
11
d1
70.07
−32.5
0.05
0.45
12
d4
87.29
−42.5
0.05
0.40
13
d7
87.26
−42.5
0.03
0.45
14
d8
78.20
<−45.0
0.03
0.49
Comp.
d9
102.9
<−45.0
0.05
0.80
Example 3
[0055] Table 2 shows the results of tests for evaluating the lubricating oil compositions in almost real conditions. The kinetic viscosity was measured at −10° C. In all examples, evaporation loss levels were as low as 0.5% or less which satisfied the standard value. In addition, the rotation property was also found to be lower than the standard value, and lubricating oil compositions having low torque at low temperature and exhibiting low evaporation at high temperature, which had a trade-off relationship and were difficult to achieve simultaneously, were obtained.
[0056] According to comparison of the compositions, the composition of Example 12 was found to have a lowest evaporation loss and a rotating viscosity lower than the standard value, while the compositions of Examples 13 and 14 prepared by adding a polyol ester were found to be excellent almost without inhibiting their evaporation losses.
[0057] It should be noted that the composition of Comparative Example 3 was considered to have a best balance among existing base oils and has been adopted in many small motors. In the present invention, development of a lubricating oil which has performance higher than that of the composition of Comparative Example 3, called “best oil,” is considered to contribute to an improvement in performance of a small motor (extension of life-time and saving of energy).
INDUSTRIAL APPLICABILITY
[0058] The lubricating oil base oil according to the present invention can provide a lubricating oil composition having characteristics of low volatility and excellent low-temperature fluidity and capable of providing long-lasting lubrication property in a wide temperature range from low temperature to high temperature. In particular, when the oil is applied to a bearing for a small spindle motor related to information equipment, it is possible to achieve low torque (in particular, low-temperature driving property) without impairing durability. | Provided are a lubricating oil base oil having characteristics of low volatility and excellent low-temperature fluidity and capable of providing long-lasting lubrication property in a wide temperature range from low temperature to high temperature, and a lubricating oil composition using the same. The lubricating oil base oil includes a diester obtained through a reaction between a diol component formed of 1,12-dodecanediol and a carboxylic acid component formed of 2-methylpentanoic acid or 2-methylpentanoic acid and 2-ethylhexanoic acid. The diester is represented by R 2 COOR 1 OOCR 3 , where R 1 represents an alkylene derived from the diol component and R 2 and R 3 each represent an alkyl derived from the carboxylic acid component, and includes 45 to 100 mol % of a diester in which both of R 2 and R 3 represent C5 alkyls. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of application Ser. No. 11/221,256 filed Sep. 6, 2005, which claims benefit to U.S. Provisional Application Ser. No. 60/608,354 filed Sep. 9, 2004. The entire content of each above-mentioned application is hereby incorporated by reference in entirety.
FIELD OF THE INVENTION
The invention relates to halogenated benzamide derivatives, and more specifically, benzamide derivatives characterized by greater specificity for viral pathogens and less disruptive to beneficial gut microflora.
BACKGROUND OF THE INVENTION
Laser (2-(acetolyloxy)-N-(5-nitro-2-thiazolyl)benzamide, the compound of formula (I), also referred to as nitrothiazole, nitazoxanide, or NTZ, is known for use in the treatment and prevention of parasitic infections, bacterial infections, fungal infections, diarrhea and other intestinal troubles (U.S. Pat. Nos. 3,950,351, 4,315,018 and 5,578,621) including treatment of trematodes (U.S. Pat. No. 5,856,348). The preparation of NTZ is disclosed in U.S. Pat. No. 3,950,351. Improved pharmaceutical compositions for delivery of NTZ are disclosed U.S. Pat. Nos. 6,117,894 and 5,968,961.
It has been postulated that, in anaerobic bacteria and protozoa, NTZ exhibits a mode of action based upon reduction of its nitro group by nitroreductases, and particularly pyruvate ferredoxin oxidoreductase (PFOR) dependent electron transfer reactions that are essential for anaerobic energy metabolism. Nothing is currently known regarding the possible mode of action of NTZ for helminthes, however, the enzymes of anaerobic electron transport are considered as potential targets, with the 5-nitro group implicated in this mechanism.
Compounds according to formula (II), in which one of R 1-5 is —OH and the remainder of R 1-5 being H, are known to exhibit antiviral activity, and are known for treatment of human viral diseases such as those caused by human cytomegalovirus, varicella zoster, Epstein Barr virus, HSV-I and HSV-II (U.S. Pat. Nos. 5,886,013 and 6,020,353).
While potent, these compounds are not selective for only viral pathogens. They are described as having excellent efficacy against parasites, bacteria and fungus. In practice, this is associated with a problem. Namely, in humans and many animals, the gut contains beneficial populations of microflora, principally comprised of anaerobic bacteria. Oral administration of broad spectrum compounds such as those of Formula (II) kills the bacterial gut flora, which may lead to secondary complications including diarrhea requiring further treatment.
Accordingly, there is a need for therapeutic compounds that are more selective for viral pathogens. Most preferably, these compounds should possess antiviral activity, but be substantially devoid of antibacterial and antiparasite activity, at least to the extent of avoiding deleterious effects upon the beneficial gut microflora when administered orally.
This need, and more, is achieved by the present invention, as will become clear to one of ordinary skill upon reading the following disclosure and examples.
SUMMARY OF THE INVENTION
The present invention relates to antiviral benzamide derivatives that are more selective for viral pathogens, and accordingly cause reduced deleterious effects upon beneficial gut microflora when administered orally.
In a first aspect, the invention is surprisingly made by replacing the nitro substituent, which has until now been believed to be the key to the activity of NTZ, with a halogen atom. This substitution may be made in any of the known therapeutically effective 2-benzamido-5-nitro-thizaoles (wherein the benzene ring may be variously substituted). Surprisingly, the novel halogenated compounds retain their antiviral properties, but they lack activity against the bacterial gut microflora when administered orally.
Examples of these known 2-benzamido-5-nitro-thizaoles, which are analogues of the compounds of the present invention differing only in that in accordance with the present invention the nitro group is removed and replaced with a halogen atom, are extensively set forth in the above referenced U.S. Patents, and U.S. Pat. No. 5,886,013 in particular, their disclosure being incorporated herein by reference.
The present invention further provides (5-halo-2-thiazolyl)benzamide compounds according to formula (III):
in which
R 1 is a halogen atom, preferably F, Cl, Br, or I, more preferably Br or Cl, most preferably Br, and
R 2 -R 6 are independently hydrogen, hydroxyl, C 1 -C 4 alkyl, —C 1 -C 4 alkoxy, acyloxy (preferably acetoxy or propionoxy), nitro, halogen, —C(O)R 7 where R 7 is —C 1 -C 4 alkyl, or, aromatic (preferably unsubstituted or substituted phenyl or benzyl), including salts and hydrates of these compounds.
Preferably, one of R 2 -R 6 is hydroxyl.
Preferably at least one of R 2 -R 6 are other than hydrogen, and more preferably at least two of R 2 -R 6 are other than hydrogen.
Two adjacent R 2 -R 6 may together form a benzyl ring.
Preferably, R 2 -R 6 include no more than one acyloxy and no more than one halogen.
The present invention further provides antiviral compounds according to formula (IV):
in which R 1 is a halogen atom, R 8 is —C(O)R 10 , where R 10 is —C 1 -C 4 alkyl, and R 9 is —C 1 -C 4 alkyl or —C 1 -C 4 alkoxy, including salts and hydrates of these compounds.
The invention further provides antiviral pharmaceutical compositions comprising a compound of Formula (III) or (IV) and a pharmaceutically acceptable carrier.
Finally, the invention provides a method of treating or preventing a viral infection in an animal or human subject, the method comprising administering to said subject at least one dose of the pharmaceutical composition comprising an effective amount of the antiviral compound according to Formula (III) or (IV) and a pharmaceutically acceptable carrier.
DETAILED DESCRIPTION
In Compounds of the present invention include those according to formula (III):
in which
R 1 is a halogen atom, preferably F, Cl, Br, or I, more preferably Br or Cl, most preferably Br, and
R 2 -R 6 are independently hydrogen, hydroxyl, C 1 -C 4 alkyl, —C 1 -C 4 alkoxy, acyloxy (preferably acetoxy or propionoxy), nitro, halogen, —C(O)R 7 where R 7 is —C 1 -C 4 alkyl, or, aromatic (preferably phenyl or benzyl, which may be further substituted), including salts and hydrates of these compounds.
Preferably, one of R 2 -R 6 is hydroxyl.
Preferably at least one of R 2 -R 6 are other than hydrogen, and more preferably at least two of R 2 -R 6 are other than hydrogen.
Two adjacent R 2 -R 6 may together form a benzyl ring.
Preferably, R 2 -R 6 include no more than one acyloxy and no more than one halogen. Compounds according to the present invention are illustrated by the following non-limiting list:
Code
Molecular
Molecular
Number
Structure
Weight
Formula
RM-4803
355.21
C 13 H 11 BrN 2 O 3 S
RM-4804
310.75
C 13 H 11 ClN 2 O 3 S
RM-4806
371.21
C 13 H 11 BrN 2 O 4 S
RM-4819
313.17
C 11 H 9 BrN 2 O 2 S
RM-4820
341.18
C 12 H 9 BrN 2 O 3 S
RM-4821
355.21
C 13 H 11 BrN 2 O 3 S
RM-4822
355.21
C 13 H 11 BrN 2 O 3 S
RM-4826
313.17
C 11 H 9 BrN 2 O 2 S
RM-4827
333.59
C 10 H 6 BrClN 2 O 2 S
RM-4831
317.13
C 10 H 6 BrFN 2 O 2 S
RM-4832
299.14
C 10 H 7 BrN 2 O 2 S
RM-4833
329.17
C 11 H 9 BrN 2 O 3 S
RM-4834
329.17
C 11 H 9 BrN 2 O 3 S
RM-4835
284.72
C 11 H 9 ClN 2 O 3 S
RM-4836
284.72
C 11 H 9 ClN 2 O 3 S
RM-4838
333.59
C 10 H 6 BrClN 2 O 2 S
RM-4839
333.59
C 10 H 6 BrClN 2 O 2 S
RM-4840
378.04
C 10 H 6 Br 2 N 2 O 2 S
Preferred examples of compounds within Formula (III) include:
2-(acetolyloxy)-3-methyl-N-(5-bromo-2-thiazolyl)benzamide (RM4803); 2-(hydroxy)-3-methyl-N-(5-bromo-2-thiazolyl)benzamide (RM4819); 2-(acetolyloxy)-N-(5-bromo-2-thiazolyl)benzamide (RM4820); 2-(acetolyloxy)-5-methoxy-N-(5-bromo-2-thiazolyl)benzamide (RM4821); and 2-(acetolyloxy)-5-methoxy-N-(5-bromo-2-thiazolyl)benzamide (RM4822).
It has further been discovered that compounds with a hydroxyl substitutent in the ortho position of the benzene ring have good efficacy. Thus, from among the above illustrative compounds, the following compounds are preferred: RM-4819, RM-4826, RM-4827, RM-4831, RM-4832, RM-4833, RM-4834, RM-4835, RM-4836, RM-4838, RM-4839, RM-4840.
Compounds according to the invention preferably include those of formula (IV):
wherein:
R 1 is halogen, preferably F, Cl, Br, or I, more preferably Br or Cl, most preferably Br,
R 8 is —C(O)R 10 , in which R 10 is —C 1 -C 4 arkyl. R 10 includes methyl, ethyl, propyl and butyl, including isomers thereof. Methyl is preferred, whereby the benzamide substituent is acetolyloxy, and
R 9 is —C 1 -C 4 alkyl or —C 1 -C 4 alkoxy. Methyl and methoxy are preferred. Methyl is most preferred.
Examples of compounds within Formula (IV) include:
2-(acetolyloxy)-3-methyl-N-(5-bromo-2-thiazolyl)benzamide (RM4803); 2-(acetolyloxy)-3-methyl-N-(5-chloro-2-thiazolyl)benzamide (RM4804); and 2-(acetolyloxy)-3-methoxy-N-(5-bromo-2-thiazolyl)benzamide (RM4806).
The compositions of the present invention may be formulated as solid or liquid dosage forms, or as pastes or ointments, and may optionally contain further active ingredients.
The pharmaceutical compositions of the present invention comprise a pharmaceutically acceptable carrier, which is not particularly limited, and includes a wide range of carriers known to those of ordinary skill in the art, and including wetting or dispersing agents (U.S. Pat. No. 5,578,621), starch derivatives (U.S. Pat. No. 5,578,621), excipients, and the like. Tablet embodiments may optionally comprise a coating of a substance that constitutes an enteric coating, i.e. a coating that substantially insoluble in gastric secretion but substantially soluble in intestinal fluids.
Pharmaceutical compositions comprising compounds according to Formula (III) or (IV) are preferably formulated for oral administration and are optionally in the form of a liquid, for example an emulsion or a solution or a suspension in water or oil such as arachis oil, or other liquid. Formulations of non-aqueous micellar solutions may be prepared according to the method disclosed in U.S. Pat. No. 5,169,846. Alternatively, tablets can be manufactured, for example, by performing the following steps: wet granulation; drying; and compression. Film coating is generally performed with organic solvents.
The term “selective antiviral” as used herein means that, at dosages effective for the prevention or treatment of a viral disease, the activity is more antiviral than antibacterial, antifangal, or antiparasite, and gut flora of the subject is not disrupted to levels expected with broad spectrum antibiotics.
The preferred antiviral treatment or prophylactic dosages of the compounds of the present invention may depend upon the weight of the subject, and may be inferred by one of ordinary skill without undue experimentation by reference to the following examples, which are set forth for purposes of illustration and are not intended to be limiting.
EXAMPLE 1
Testing Against Viruses
Methods
Non-Hepatic Viruses
Cell cultures and Treatments. HEp-2 laryngeal carcinoma cells, monkey kidney 37RC, MA104 and VERO cells, canine Madin-Darby kidney (MDCK) and mammary adenocarcinoma (A72) cells, were grown at 37° C. in a 5% CO 2 atmosphere in RPMI medium (Gibco-Invitrogen, Carlsbad, Calif.), supplemented with 10% fetal calf serum (FCS), 2 mM glutamine and antibiotics. Compounds dissolved in DMSO stock solution (50 mg/ml) were diluted in culture medium and added to infected cells immediately after the 1 hour adsorption period. Compounds were maintained in the medium for the duration of the experiment. Controls received equal amounts of DMSO diluent. Each concentration of each compound was tested in duplicate and each experiment was repeated twice.
Virus infection and titration. The following viruses were utilized: Influenza A: strain Puertorico (PR8); Paramyxovirus (Parainfluenza): Sendai virus (SV); Rhabdovirus: Vesicular Stomatitis Virus (VSV); Rotavirus: Simian Rotavirus SA-11 (SA-11); Herpes Simplex virus type 1: strain F1 (HSV-1); Coronavirus: canine coronavirus strain S-378 (CCoV). Confluent cell monolayers were infected with Influenza A virus (MDCK cells) or parainfluenza SV (37RC cells) for 1 h at 37° C. at a multiplicity of infection (m.o.i.) of 5 HAU (Hemagglutinating Units)/10.sup.5 cells. Alternatively, confluent cell monolayers were infected with HSV-1 (HEp-2 cells), VSV (MA104 cells), CCoV (A72 cells) or Rotavirus SA-11 (MA104 cells) for 1 h at 37° C. at a m.o.i. of 5 PFU (Plaque Forming Units)/10 5 cells for HSV-1, VSV and CCoV and 1 PFU/10 5 cells for SA-11. After the adsorption period, the viral inoculum was removed and cell monolayers were washed three times with phosphate-buffer saline (PBS). Cells were maintained at 37° C. in appropriate culture medium containing 2% FCS in the presence of the test compound or control diluent. Virus yield was determined 24 hours post infection (p.i.) by hemagglutinin titration (WSN, PR8, SV and SA-11) or CPE50% assay (VSV, HSV-1, and CCoV), according to standard procedures (Amici, C., Belardo, G., Rossi, A. & Santoro, M. G. Activation of IκB kinase by Herpes Simplex virus type 1 . A novel target for anti - herpetic therapy. J. Biol. Chem. 276, 28759-28766 (2001) and Bemasconi, D., Amici, C., La Frazia, S., Ianaro, A. & Santoro, M. G. The IκB kinase is a key factor in triggering Influenza A virus—induced inflammatory cytochine production in airway epithelial cells. J. Biol. Chem. 280, 24127-24134 (2005)).
Cell toxicity. Cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to MTT formazan conversion assay (Sigma-Aldrich, St Louis, Mo.). For MTT assay, reduced MTT (formazan) was extracted from cells by adding 100.mu.l of acidic isopropanol containing 10% Triton X-100, and formazan absorbance was measured in an ELISA microplate reader at two different wavelengths (540 and 690 nm).
Hepatitis B Virus
Anti-Hepatitis B Virus (HBV) analyses and an assessment of cytotoxicity were performed in a 9-day assay in the chronically-producing HBV human hepatoblastoma cell line, 2.2.15, as previously described (Korba, B. E. & Gerin, J. L. Use of a standardized cell culture assay to assess activities of nucleosides analogues against hepatitis B virus replication. Antivir. Res. 19, 55-70 (1992)).
Hepatitis C Virus
Anti-Hepatitis C Virus (HCV) analyses and an assessment of cytotoxicity were performed in a 3-day assay in the HCV replicon-containing human hepatoblastoma cell line, AVA5 (Okuse, C., Rinaudo, J. A., Farrar, K., Wells, F. & Korba, B. E. Enhancement of antiviral activity against hepatitis C virus in vitro by interferon combination therapy. Antivir. Res. 65, 23-34 (2005)) as previously described (Blight, K. J., Kolykhalov, A. A. & Rice, C. M. Efficient initiation of HCV RNA replication in cell culture. Science 290, 1972-1974 (2000)).
Results of Testing Against Viruses
TABLE 2
Activity of other compounds against paramyxovirus:
sendai virus in cell culture.
Paramyxovirus: Sendai virus
Compound
EC 50 (μM)
SI
RM-4820
0.34
35
RM-4821
0.36
>50
RM-4822
0.36
7
EC 50 = drug concentration at which a 2-fold depression of viral RNA (relative to the average levels in untreated cultures) was observed. CC 50 = drug concentration at which a 2-fold depression of reduced MTT was observed relative to average levels in untreated cultures. SI (selectivity index) = CC 50 /EC 50 .
TABLE 1
Activity of RM-4803 and RM-4819 against viruses in cell culture.
EC 50 (μM)/SI
Virus
RM4819
RM4803
Cell Culture
Rotavirus: Simian rotavirus
0.3/>500
0.06/>2500
MA104
SA-11
Influenza A: PR8 strain
9.6/>17
2.8/>50
MDCK
Paramyxovirus: Sendai virus
1.3/>125
1.1/>125
37RC
Coronavirus: canine
4.9/>33
4.2/13
A72
coronavirus strain S-378
Rhabdovirus: Vesicular
1.6/>100
2.8/>50
MA104
stomatitis virus
Herpes Simplex type 1:
0.6/>250
5.6/3
HEp-2
strain F1
EC 50 = drug concentration at which a 2-fold depression of viral DNA or RNA (relative to the average levels in untreated cultures) was observed. CC 50 = drug concentration at which a 2-fold depression of reduced MTT was observed relative to average levels in untreated cultures. SI (selectivity index) = CC 50 /EC 50 .
TABLE 3
Activity of compounds against HBV replication in 2.2.15 cell culture.
Extracellular
Intracellular
Selectivity
Virion DNA
HBV R.I.
Index
Compound
EC 50 (μM)
EC 90 (μM)
EC 50 (μM)
EC 90 (μM)
CC 50 (μM)
Virion
R.I.
Lamivudine
0.058 ± 0.006
0.164 ± 0.015
0.172 ± 0.020
0.660 ± 0.068
2229 ± 76
12959
3377
RM4803
6.3 ± 0.7
15 ± 1.1
12 ± 1.5
50 ± 5.5
>1000 §
>67
>20
RM4819
3.5 ± 0.5
9.0 ± 0.8
7.6 ± 0.9
22 ± 2.6
>1000 §
>111
>46
§ No significant cytotoxic effects were observed up to the highest indicated concentration.
Values presented (±standard deviations [S.D.]) were calculated by linear regression analysis using data combined from all treated cultures. S.D. were calculated using the standard error of regression generated from linear regression analyses (QuattroPro.™). EC 50 , EC 90 32 drug concentration at which a 2-fold, or a 10-fold depression of HBV DNA (relative to the average levels in untreated cultures), respectively, was observed, CC 50 =drug concentration at which a 2-fold depression of neutral red dye uptake (relative to the average levels in untreated cultures) was observed, The EC 90 values were used for the calculation of the Selectivity Indexes [S.I.] since at least a 3-fold depression of HBV levels is typically required to achieve statistical significance in this assay system. HBV R.I.=intracellular HBV DNA replication intermediate.
TABLE 4
Activity of compounds against hepatitis C
virus replication in AVA5 cell culture.
Selectivity
Compound
CC 50 (μM)
EC 50 (μM)
EC 90 (μM)
Index
∝ -
>10,000* §
2.2 ± 0.2*
8. ± 0.6*
>4,545
Interferon
Ribavirin
61 ± 2.9
94 ± 10
>100 §
0.6
RM4803
282 ± 21
37 ± 2.7
98 ± 9.3
7.6
RM4819
164 ± 18
8.9 ± 0.7
79 ± 8.2
18
*Values for interferon are expressed as “IU/ml.”
§ No significant cytotoxic or antiviral effects were observed up to the highest indicated concentration.
Values presented (±standard deviations [S.D.]) were calculated by linear regression analysis using data combined from all treated cultures. S.D. were calculated using the standard error of regression generated from the linear regression analyses (QuattroPro.™). EC 50 , EC 90 =drug concentration at which a 2-fold, or a 10-fold depression of HCV RNA (relative to the average levels in untreated cultures), respectively, was observed. CC 50 =drug concentration at which a 2-fold depression of neutral red dye uptake was observed relative to the average levels in untreated cultures. Selectivity index=CC 50 /EC 50 .
EXAMPLE 2
Testing Against Anaerobic Bacteria
Methods. Recent clinical anaerobic isolates (2000 to date) comprised 40 B. fragilis group, 26 Prevotella/Porphyromonas, 28 fusobacteria, 16 anaerobic Gram positive cocci, 14 anaerobic Gram-positive non-sporeforming rods and 18 clostridia. CLSI agar dilution MIC methodology with enriched Brucella blood agar and inocula of 1.times.10.sup.5 cfi/spot was used. Plates were incubated in an anaerobic glove box at 35° C. for 48 h.
Results. MIC 50 /MIC 90 values (μg/ml) were as follows:
B. fragilis
Gram +
Gram +
gp
Prev/Porphy
Fusobacteria
cocci
rods
Clostridia
All
Drag
(40)
(26)
(28)
(16)
(14)
(18)
(142)
Nitazoxanide
2/4
4/8
1/4
0.5/2
16/>32
0.5/4
2/4
Tizoxanide
2/4
2/16
0.5/2
0.5/1
8/>32
0.25/2
2/4
RM 4803
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
RM 4819
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
>32/>32
Amoxicillin-
1/4
0.06/0.5
0.5/4
0.125/0.5
0.25/1.0
0.125/1.0
0.5/2.0
clavulanic
acid
Clindamycin
2/>32
<0.015/<0.015
0.06/0.125
0.125/0.5
0.125/4
l/>32
0.125/8.0
Metronidazole
1/2
0.5/2
0.25/0.25
0.5/1.0
>16/>16
0.25/2
1.0/2.0
Results showed that nitazoxanide, tizoxanide, potent against all anaerobic bacteria groups except for Gram-positive anaerobic rods including lactobacilli (which are in reality mostly microaerophils). By contrast, RM 4803 and RM 4819 were without significant activity.
EXAMPLE 3
Antiviral Activity
Compounds within Formula (IV) of the present invention exhibit potent antiviral activity, as shown in Table 5.
Activity of RM-4803, RM-4804 and RM-4806
against viruses in cell monolayer
Human Rhinovirus Type 39
Influenza A Virus
OH-Hela
MDCK
2% McCoys + Hepes
0% EMEM +
Buffer
Hepes + Trypsin
Microscopic
Microscopic
Compound
Spectrophotometer
Spectrophotometer
R 1 = Br
0.06
0.03
0.45
0.18
R 2 = acetolyloxy
R 3 = methyl
(RM 4803)
R 1 = Cl
0.57
0.32
0.93
0.57
R 2 = acetolyloxy
R 3 = methyl
(RM 4804)
R 1 = Br
5.0
4.0
0.46
0.57
R 2 = acetolyloxy
R 3 = methoxy
(RM 4806)
Pirodavir
0.007
0.004
NA
NA
Oseltamivir
NA
NA
0.13-0.17
0.08-0.36
EC 50 (.mu.g/mL) values for 2-(acetolyloxy)-3-methyl-N-(5-bromo-2-thiazolyl)benzamide (RM4803), 2-(acetolyloxy)-3-methyl-N-(5-chloro-2-thiazolyl)benzamide (RM4804), and 2-(acetolyloxy)-3-methoxy-N-(5-bromo-2-thiazolyl)benzamide (RM4806), on Human Rhinovirus Type 39 (HRV-39), and H 3 N 2 influenza virus, type A, using a multiple cycle CPE inhibition assay on OH—I Hela and Madin Darby Canine Kidney (MDCK) cell monolayers, respectively, were measured by microscopic and spectrophotometric methods. Pirodavir and Oseltamivir were included as positive controls.
EXAMPLE 4
Selective Anti-Viral Activity
The above identified compounds according to Formula (IV) were tested by conventional means against Trichomis vaginalis, Giardia Intestinalis , and Trypanosoma brucei. 2-(acetolyloxy)-3-methyl-N-(5-bromo-2-thiazolyl)benzamide (RM4803), 2-(acetolyloxy)-3-methyl-N-(5-chloro-2-thiazolyl)benzamide (RM4804), and 2-(acetolyloxy)-3-methoxy-N-(5-bromo-2-thiazolyl)benzamide (RM4806) each failed to exhibit antiparasite activity against Trichomonas vaginalis, Giardia intestinalis , or Trypanosoma brucei at concentrations of at least 50 μg/mL.
Accordingly, it has been demonstrated that in accordance with the present invention, novel compounds can be provided which are generally characterized by selective antiviral activity.
As an additional benefit, it has been discovered that the above halogen-substituted benzamide compounds are effective against intracellular protozoa including Cryptosporidium spp., Neospora spp. and Sarcocystis neurona (RM-4820, RM-4821 and RM-4822).
With respect to the above description, it is to be realized that the optimum formulations and methods of the invention are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
Certain references, patents and other printed publications have been referred to herein: the teachings and scope of each of said publications are hereby incorporated in their respect entireties by reference.
Now that the invention has been described: | A halogenated benzamide derivative characterized by greater specificity for viral pathogens and less disruptive to beneficial gut microflora, according to formula (III): in which R 1 is a halogen atom, and R 2 -R 6 are independently hydrogen, hydroxyl, C 1 -C 4 alkyl, —C 1 -C 4 alkoxy, acyloxy, nitro, halogen, —C(O)R 7 where R 7 is —C 1 -C 4 alkyl, or, aromatic including salts and hydrates of these compounds and where at least two of R 2 -R 6 are not hydrogen and where at least one of R 2 -R 6 are hydroxy or acyloxy. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to and is a continuation in part of U.S. application Ser. No. 14/077,714 filed Nov. 12, 2013, entitled Healthcare Data Management System, which claims priority to Provisional patent applications: Application No. 61/725,709 filed Nov. 13, 2012; Application No. 61/781,125 filed Mar. 14, 2013; Application No. 61/826,677 filed May 23, 2013 and Application No. 61/841,977 filed Jul. 2, 2013; all of the above-referenced application having inventors: Nicholas G. Anderson, John S. Pollack and David F. Williams
FIELD
[0002] This invention relates to the field of computer generation of medical records for customers and particularly relates to computer generation and modification of medical records for customers that are subject to specific rules or restrictions on the content of medical records.
BACKGROUND
[0003] Medical records are created and reviewed for a variety of purposes. For example, universities and other research facilities obtain and modify medical records for pure research purposes. Medical records include records from patient charts, electronic health records, medical billing records, drug-inventory system records, and any other health record. Also, companies that produce medicines or medical products study medical records to judge and improve the effectiveness, efficiency and acceptance of their products. Because of government laws, rules and regulations, some companies are careful to avoid some type of information about their own products. For example, medical products are often used by doctors for purposes and treatments that are not approved by the FDA. These uses are sometimes called off-label uses. A company is not allowed to promote off-label uses of its products and therefore some companies avoid any research that might include a review of medical records depicting off-label use of their products. Such research might be construed as an attempt to promote the off-label use. This self-imposed or government imposed handicap reduces the ability of companies and other researchers to fully and completely research medical records with respect to certain drugs and other medical products.
[0004] In accordance with the present invention, medical records are created and modified based upon the needs of the user, also called a customer. In addition to selecting information needed by a user from a database, the present invention identifies and eliminates information from the medical records that is not needed or wanted. For example, a particular customer may be interested in researching actual medical records concerning the use of a drug, but it may be inappropriate for the company to study medical records related to off-label use of the drug. Government rules might actually forbid a drug manufacturer from studying such off-label uses in some circumstances. So to comply with applicable laws and rules, a drug manufacturer may avoid particular types of medical records related to off-label use. However, even medical records relating to off-label uses may be useful in particular research related to particular drugs. The present invention has recognized a need to provide a special form of medical records in which certain types of medical information is removed from the medical report so that the medical records may be considered, but the records will not include information that a customer does not wish to see for whatever reason.
[0005] In accordance with one embodiment of the present invention, a method is disclosed for computer creating a desired report from a computer database of health information. The desired report is prepared for a customer who provides input data indicating the type of report desired. A computer database is created by receiving from healthcare providers a plurality of electronic encounter records. Each encounter record includes medical information. The computer further receives input data relating to the medical information that the customer wishes to include in the desired report. The input data may include items to be included in the report or items to be excluded from the report. The computer analyzes the patient encounter records in the database to identify and select a subset of patient encounter records based on the input data. The computer analyzes the subset of patient encounter records to identify and remove medical information to thereby create a sub-subset of medical information again based on the input data provided by the customer. A desired report is computer generated from the patient encounter records based on the sub-subset of medical information.
[0006] The input data controls what medical information is included and excluded in a desired report, but it does not necessarily do so directly. The meaning of the input data may be controlled by internal rules. For example, if a customer identifies codes that should be included in the desired report, an internal rule may provide that all other codes should be redacted from the report. Thus, by identifying included codes, the customer has indirectly identified excluded codes as well. Likewise, the customer may identify excluded codes, and the program may have an internal rule that will redact all of the excluded codes, but all of the remaining medical information including other codes will be included in the desired report. Thus, by identifying excluded codes, the customer has also identified what information should be included in the report. The internal rules are crafted based on government regulations that sometimes forbid the company to view certain types of data. For example, a drug manufacturer may be forbidden from investigating unapproved uses of a particular drug. In such case, if a customer identifies a particular drug as included data, an internal rule may provide that all codes and words relating to known unapproved uses of that drug should be redacted from the report.
[0007] The input data may include one or more desired codes or words that the customer wishes to include in the report. In such case the computer may identify and select the subset of encounter records to include encounter records with the desired codes or words or both. Other codes may be included in this subset as well. The computer may then analyze the subset to remove (redact) the other codes (not the desired codes). The computer then generates the desired report to include the desired codes or words and other medical information but not including the other codes or words. In addition, words or other information related to the other codes or words may be similarly redacted from the final report to the customer.
[0008] In another embodiment the customer may identify one or more excluded codes and/or words that the customer wishes to exclude from the report. Based on the excluded codes or words or both, the computer creates the subset and sub-subset. The sub-subset may include medical records that originally contained the excluded codes or words, but such excluded codes and/or words are now redacted. Alternatively, records containing the excluded codes or words may be removed entirely.
[0009] In accordance with a more particular embodiment, the computer may identify first and second groups of diagnosis codes based on the input data. Then, patient encounter records that include the first group are included in the subset. The sub-subset is created by excluding information from the subset based on the second group. Entire records may be excluded or portions of records excluded based on the second group of diagnosis codes.
[0010] The program may further identify additional included or excluded items based on either included or excluded items. For example, if a particular diagnosis code is indicated as an included item, then the words used to identify the diagnosis would be generated as additional included items. However, excluded items may also be generated based on the included diagnosis code. For example, if the diagnosis code indicates a particular disease, and it is known that a particular drug is sometimes used by doctors to treat that particular disease, but it is not an FDA approved treatment, the medicine code and name of the particular drug may be identified as an excluded item. This input of information may be provided internally through lookup tables or externally by a user answering questions.
[0011] In accordance with yet another variation, the input data may include particular codes and particular words. The computer creates a subset and then analyzes the subset of data removing the particular words from each patient encounter record in the subset if said each patient encounter record does not include at least one of the particular codes. Thus, the subset will include patient encounter records with the particular words removed and will also include patient encounter records with the particular words included and with at least one of the particular codes included.
[0012] In yet another embodiment, the input data includes particular diagnosis identifiers and particular medicine identifiers. When creating the subset, the computer removes at least one of:
[0013] (1) all of the particular diagnosis identifiers, and/or
[0014] (2) all of the particular medicine identifiers,
[0000] from each patient encounter record in the subset. The decision as to what should be removed is based upon the presence or absence of the particular diagnosis identifiers in each patient encounter record and based upon the presence or absence medicine identifiers in each patient encounter record. For example, the particular medicine identifiers may be removed from each patient encounter that does not include at least one of the particular diagnosis codes. Alternatively, the particular medicine identifiers may be removed from each patient encounter that includes at least one of the particular diagnosis codes. When information is removed from an encounter record it may be replaced with nothing as if it never existed, or it may be replaced with a placeholder such as “XXXXXXXX”.
[0015] In accordance with yet another embodiment a desired report is created from a computer database for a customer where the database includes a plurality of electronic encounter records with medical information within each encounter record. A set of exclusion data is provided to the computer. The exclusion data is related to medical information that the customer wishes to be excluded from the desired report. Based on the exclusion data, the computer analyzes the electronic patient encounter records to identify a subset of patient encounter records that should be excluded. The computer generates the desired report by including all patient encounter records except for the excluded sub-subset of the patient encounters.
[0016] In a variation of this embodiment, based on the particular set of exclusion data, the computer may identify additional exclusion data. Then, based on the original exclusion data and the additional exclusion data, the computer generates the desired report excluding a second subset of patient encounters from the desired report (or excluding a second subset of patient information within the patient encounters).
[0017] As a particular example of the above method the exclusion data may comprise particular diagnosis identifiers and particular medicine identifiers. The computer may create a subset that includes patient encounter records based on the presence or absence of at least one of the particular diagnosis identifiers and further based on the presence or absence of at least one of the particular medicine identifiers. For example, a patient encounter record may be excluded from the report if one of the diagnosis identifiers is present in the encounter record and one of the medicine identifiers is also identified in the encounter record. As another example a patient encounter record may be excluded from the report if one of the diagnosis identifiers is not present in the encounter record and one of the medicine identifiers is present in the encounter record.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Further advantages of the invention are apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein:
[0019] FIG. 1 illustrates diagnosis records for four patients showing diagnoses for each of five different encounters (Patient Encounter IDs 2886 and 4001 correspond to patient with Patient ID 1764; Patient Encounter IDs 2887, 2888, and 2891 correspond to patients with Patient IDs 1765, 1766, and 1767, respectively);
[0020] FIG. 2 is patient information record for four different patients showing a unique Patient ID for each patient;
[0021] FIG. 3 is a patient encounter record showing five different encounters with four patients identified in FIG. 2 ;
[0022] FIG. 4 . is a patient procedure record for each of the five encounters of FIG. 3 ;
[0023] FIG. 5 is a patient procedure medications record for each of the five encounters of FIG. 3 showing a medication name, procedure notes, and a medication code; and
[0024] FIGS. 6A-6E are patient finding records showing numerous findings for each of the encounters of FIG. 3 .
DETAILED DESCRIPTION
Diagnosis Record Example
[0025] The methods of the present invention are implemented on computer systems that store medical records and may include computers owned by physicians, hospitals, other health care providers, outside vendors supplying computer record services to health care providers, a database owner, and customers interested in purchasing medical information. These computers are typically in different locations but are connected by intranet or internet connections. Referring to FIG. 1 , there is shown in abbreviated exemplary subset of a medical record for purposes of explaining various embodiments of the invention. FIG. 1 shows only a few medical diagnosis records for only four patients and it represents the medical records that were pulled from a larger database based on a request from a customer.
[0026] To begin the preparation of a report in accordance with this embodiment, a database of medical records stored on a computer is first searched for terms of interest. Any patient encounter record that satisfies terms of interest will be returned as “hits”. Then the hits are analyzed to determine whether any information should be excluded based on the customer search request and various internal and external rules. Alternatively, all records in the database may be analyzed.
[0027] Referring to FIG. 1 , a simple subset of a medical database is shown. The patients are identified only by a code and thus these medical records have been de-identified in accordance with U.S. patent application Ser. No. 14/077,714, filed Nov. 12, 2013, entitled Healthcare Data Management System, which is incorporated herein by reference. In this case, in FIG. 1 five patient encounters are listed in the first column, numbered 2886, 2887, 2888, 2891, and 4001. In the second column the patient identification numbers are shown as follows 1764, 1765, 1766 and 1767. In the fourth column a diagnosis code is provided. In this hypothetical, the subset shown in FIG. 1 was generated by searching a database for Lucentis or Eylea or Vancomycin. Elsewhere in the medical records these search words appeared.
[0028] As used in the figures, the ICD9 codes of interest are as follows:
[0029] 362.52 is exudative AMD (macular degeneration)
[0030] V43.1 is pseudophakia (ie a patient who has had cataract surgery)
[0031] 360.00 is endophthalmitis, an infection of the eye
[0032] 362.07 is diabetic macular edema (diabetic eye disease)
[0033] 250.5 is systemic diabetes with ocular complications
[0034] 436 is stroke
[0000] The following abbreviations are used in the Figures:
[0035] OD is right eye
[0036] OS is left eye
[0037] OU is both eyes
[0038] Assume that the customer had further requested that off-label uses for these drugs not be reported. The program would then analyze and further modify the report. As shown in FIG. 1 , column four, Patient 1765 has macular degeneration (code 362.52) in both eyes and has had cataract surgery (code v43.1). To determine whether any information should be deleted with respect to this patient, a lookup table is consulted. The table includes entries for each of the drugs mentioned above and those entries are correlated to inclusion data and exclusion data. In this case, the macular degeneration code 362.52 and the cataract surgery code v43.1 is found in the inclusion data for Lucentis and Eylea. Thus, for patient 1765, the computer selects the diagnosis records for patient encounter record 2887 related to patient 1765 for inclusion in the final report that is ultimately transmitted to the customer.
[0039] Patient 1764 has macular degeneration in both eyes and has had cataract surgery. However, the patient also has a diagnosis endophthalmitis in encounter 4001. The computer again checks the lookup table and discovers that the code 360.00 and/or the word “endophthalmitis” is found in the exclusion data correlated with Lucentis and Eylea. Thus, the customer would not want to see code 360.00, so the computer program removes the code 360.00 from the medical record when it generates the report that is sent to the customer. The customer still wants the other information on that patient. So the program selects everything else in that encounter record except that one code (embodiment 1) and includes the other information in the final report. The decision to include the other information was made by the customer before the report was generated.
[0040] Alternatively, the customer could provide input data requesting that the program delete an encounter altogether if any of the exclusion data is located in the encounter. So, in this case, in this alternate embodiment, all data on patient 1764 related to encounter 4001 (listing code 360.00) would be eliminated. However, all data on patient 1764 related to encounter 2886, prior to the development of endophthalmitis, would be included.
[0041] Patient 1766 has diabetic macular edema in both eyes and systemic diabetes. Elsewhere in the encounter records for this patient, it is shown that the patient an Eylea injection. However, Eylea is not approved for diabetic macular edema. So the Eylea manufacturer does not want to see where their medication was used off-label. Since these encounters all included the word Eylea and/or a code for that medication, the lookup table is consulted for Eylea and the table indicates that code 362.07 is an excluded code. So, again, the program may either remove these encounters altogether, or it could only remove the diagnosis code elements, or it could remove the name and code of the drug. All of the other elements (clinical findings, visual acuity, etc) may be included in the final report because that is still valuable information. Again, the program decides what information to remove based on initial customer instructions or, in the absences of customer instructions, based on internal rules. As before, the customer may instruct the program to remove an entire encounter record if it includes any of the exclusion data.
[0042] Customer Input
[0043] To begin the search process, the computer program must receive information from the customer as to what search is needed. Preferably, this information is provided directly by the customer through a customer portal, such as a computer, tablet or smart phone. The process begins by asking questions that will dictate the type of search that is performed and the type of report provided. Below is an exemplary set of questions and answers using fictitious codes and random diseases or drugs.
Question: What drug or product are you interested in? Answer: lucentis Question: What codes and words do you want to see? Answer:
diagnosis codes: 123 medication codes: 345, 678 treatment codes: 910 words: macular degeneration, lucentis
Question: If a patient encounter record includes extra codes that you have not chosen above, which of the below options should be applied? (Check one box.) Answer: ______A. The entire patient encounter record with extra codes should be excluded from the report. XX B. The patient encounter record with extra codes should be included in the report, and the extra codes should be removed. ______C. The patient encounter record should be included in the report and the extra codes should also be included in the report. Question: What diagnosis code and words do you NOT want to see? Answer:
diagnosis codes: 234 medication codes: 689 treatment codes: none words: colorectal cancer
Question: If a patient encounter record includes codes or names that you have chosen NOT to see, which of the below options should be applied? XX A. The entire patient encounter should be excluded from the report. ______B. The patient encounter record should be included in the report, and the excluded codes and excluded names should be removed. ______C. The patient encounter record should be included in the report and the excluded codes and the excluded names should be shown as redacted from the report.
[0067] In response to the answers to the questions above, the computer program will first conduct a search of the de-identified medical records looking for the codes 123, 345, 678 and 910. It will also search for the words macular, degeneration and Lucentis. If any of those codes or words are found in a patient encounter record, the patient encounter record is included in a subset of the de-identified medical records. The subset of medical records is then processed in accordance with the answer to question C. In this particular case, the subset will be searched for any codes other than the above listed codes. If such other codes are found in the patient encounter records, such other codes are removed or deleted leaving behind only empty space. Had the user checked box A, the entire patient encounter record with extra codes would have been deleted. If box C had been checked, the patient record would be included in the report and the extra codes would also be shown in the report.
[0068] After the above analysis, the computer program continues to analyze the subset. In response to questions D and E, the program will recognize that there is a conflict between the instructions provided in response to question C and in response to question E. With respect to the excluded codes and words, identified in response to question D, the customer has requested that the entire patient encounter record be excluded from the report. Such excluded codes would also be “extra codes” that were identified in response to question B. For those extra codes, the customer has requested that the extra codes be removed, but the patient encounter record should be included in the report. The program will take the more exclusive approach, meaning that it will analyze the original subset and it will exclude patient records that include the excluded codes and words identified in response to question D. Then, after such patient records have been excluded, the program will remove the “extra codes” from the subset which creates a sub-subset in which some of the encounter records have been removed and some codes and words have been removed from the remaining encounter records. A report is generated for the customer based on the information in the sub-subset.
[0069] In the above embodiments, the customer is prompted by the computer to make a series of decisions that may be confusing to some customers. In an alternate embodiment, the customer is asked to describe the information to be included in the report. The customer may respond by describing information to be included or excluded or both. The program then responds to the description based on a set of internal rules to develop a search strategy. In general, the program searches for words and codes that are mentioned positively by a customer. If the customer mentions words or codes in a negative context, those words and codes are redacted from the records and replaced with “XXX” or the like. For example, if the customer said: “I want to see things on Lucentis but don't include off-label uses.” The program interprets this sentence as requesting a report on Lucentis because is follows a positive verb. It interprets off-label uses as exclusion data because it follows a negative verb structure (don't). In this case, since the customer provided exclusion data, information is redacted from the report based on the exclusion data, and no other information is redacted or omitted.
[0070] In another simplified embodiment, the search strategy is heavily biased to exclude certain types of data that most customers do not want to see. For example, if a customer just requested a report on “Lucentis” and provided no negative input, this embodiment will automatically assume that the customer does not want to see off-label uses or possible adverse side effects of Lucentis. Thus, by default the computer will redact information from the report that indicates off-label uses or possible adverse side effects based on a look up table for Lucentis that identifies the things that should not be reported if the customer requests only a Lucentis report and provides no other information. Alternatively, the computer will not report an encounter in which off-label uses or possible adverse side effects are found. In this embodiment, a customer can request to see the search strategy and it will be provided, but the default report would not include the search strategy.
[0071] Exemplary Data
[0072] The data shown in FIGS. 1-6 represent a more complex example than those discussed above but the data is still simplified for ease of discussion. The data includes five encounters (encounter numbers 2886, 2887, 2888, 2891, and 4001) from four patients (patients 1764, 1765, 1766, and 1767). The basic patient data is shown in FIG. 2 , and the encounter records are shown in FIG. 3 .
[0073] As shown in FIGS. 1 , 3 and 4 , Encounter 2886 is for Patient 1764. Patient 1764 has bilateral (OU) wet AMD (macular degeneration) and at encounter 2886 received bilateral injections of Eylea. Wet AMD is an on-label indication for Eylea.
[0074] Encounter 2887 is for Patient 1765. Patient 1765 has wet AMD in the OS and at encounter 2887 received a Lucentis 0.5 mg injection OS. Wet AMD is an on-label indication for Lucentis 0.5 mg.
[0075] Encounter 2888 is for Patient 1766. Patient 1766 has Diabetic Macular Edema (DME) in the both eyes (OU) and at encounter 2888 received an Eylea injection OU. DME is off-label (unapproved) for Eylea.
[0076] Encounter 2891 is for Patient 1767. Patient 1767 has Diabetic Macular Edema (DME) in both eyes (OU) and at encounter 2891 received Lucentis 0.3 mg injection OU. DME is an on-label indication for Lucentis 0.3 mg. Note also, however, that this patient also received a diagnosis of acute stroke (ICD9 code 436) at this visit which would be considered an adverse event.
[0077] Encounter 4001 is again for Patient 1764, but this is a follow-up visit from encounter 2886. This time the patient presents with a complication (endophthalmitis, aka infection in the eye, ICD9 360) in the OD potentially due to an Eylea injection they received at encounter 2886. At encounter 4001 they receive an intravitreal injection of vancomycin in the right eye to treat that infection.
[0078] FIG. 2 is a worksheet called “Patients” and provides the Patient IDs and some information on each patient. Each patient has a unique numerical PatientID that is the same for each office visit.
[0079] The third worksheet, FIG. 3 , “Encounters” ties each patient to a specific encounter. Each encounter receives a numerical ID. It is this “PatientEncounterID” that ties all the worksheets together.
[0080] Each worksheet is for a different element of the patient encounter (diagnoses at that encounter, medications at that encounter, etc). Each worksheet includes the PatientEncounterID and the clinical elements associated with that encounter. So for each worksheet we have information from several encounters.
[0081] So, for each worksheet ( FIGS. 1-6 ), it is the PatientEncounterID that ties the findings to each patient. The PatientID is not needed on each worksheet as the PatientEncounterID indirectly provides the PatientID by cross-referencing the Encounters worksheet.
[0082] The worksheets of interest for this example are “patients” ( FIG. 2 ), “encounters” ( FIG. 3 ), “procedures” ( FIG. 4 ), “procedure medications” ( FIG. 5 ), “patient encounter findings” ( FIGS. 6A-6E ) and “diagnosis” ( FIG. 1 ). Procedure Medications” is essentially the same as “Procedures” with additional information such as medication CPT code.
[0083] Below are some representative examples of how the embodiments in the application would be applied to the medical data to create a customer report. First, the customer inputs the following:
Question: What medicine or product are you interested in? Answer: Lucentis, Eylea Question: If an encounter indicates an off-label use of a medicine, what should be included in the report? Select only one answer. Answer: ______Include all information about off-label use. ______delete the entire encounter from the report, XX delete the medicine name and medicine code, but report the rest of the encounter record, or ______delete all information about off-label use, but report the rest of the encounter record. Question: If an encounter indicates an adverse event that may be related to the medicine or product of interest, what should be included in the report? Select only one answer. Answer: ______Include all information about off-label use. XX delete the entire encounter from the report, ______delete the name and medicine code, but report the rest of the encounter record, or ______delete all information about off-label use, but report the rest of the encounter record.
[0098] In this case the customer is interested in Lucentis and Eylea, and the customer wants the medicine name and code deleted if off-label use is indicated.
[0099] The program first analyzes encounter 2886. It searches the encounter for Lucentis or Eylea. It finds Lucentis, which is a medicine of interest. The program then determines the patient ID is 1764 based on the encounter records at FIG. 3 and it finds and retrieves all encounter records for patient 1764, which are records 2886 and 4001. The program then consults the lookup table which includes the following entry:
[0000]
Excluded
Excluded
Med
Off-Label
Adverse
Medicine
Code
Inclusion
Use
Event
Eylea
j3490
Wet AMD, 362.52
DME,
stroke, 436, 360,
362.07,
Endophtalmitis
Lucentis
j2778
Wet AMD, 362.52,
stroke, 436, 360,
DME, 362.07
Endophtalmitis
[0100] Based on the lookup table, the program determines that Wet AMD and code 362.52 are included terms for Lucentis and both terms are found in the encounter records 2886. Thus the program initially includes both records 2886 and 4001. However, the program also determines that “Stroke” and “Endophthalmitis” are found in encounter 4001 and both are excluded adverse events. Based on the instructions provided by the customer, encounter record 4001 is entirely excluded from the report to the customer.
[0101] The program continues its analysis by moving to the next patient encounter that has not yet been analyzed, which is encounter 2887. Checking FIG. 3 , it is determined that the patient ID is 1765 and all encounter records for patient 1765 are pulled. In this case there is only one. Patient 1765 has wet AMD in the OS and at encounter 2887 received a Lucentis 0.5 mg injection OS. Referring to the lookup table above, the program determines that Wet AMD is an on-label indication for Lucentis 0.5 mg. None of the excluded terms are found for this patient, so the report will include all information for this patient.
[0102] The program then moves to Encounter 2888. Here we have an off-label utilization of a medication. Based on the instructions, the program deletes “Eylea” and “J3490” from the entire encounter 2888, but includes other information related to the encounter in the report less the excluded items.
[0103] The program then moves to the next unexamined encounter, and it finds encounter 2891. This encounter is initially included because it has some of the included items based on the customer instruction. However, it also includes an adverse event and code, Stroke and 436, and thus, the entire encounter record 2891 is excluded from the report.
[0104] The program may be set up to exclude or include data according to a variety of rules internal to the program and rules based on different instructions provided by the customer. As an example of an internal rule, assume the customer had only identified Excluded Off-Label uses. The program may have an internal rule to exclude any encounter that includes such Off-Label uses, but include every other encounter in the database. In an alternate embodiment, the internal rule for the same instructions may be to remove the name and code of the excluded off-label use, and include the encounter in the report.
[0105] As an example of changing rules based on customer instructions, the same situation above may be controlled by questions to the customer. For example, assume the customer has provided only excluded off-label uses. In this case, the program may respond with the question and answers shown below:
Question: You have provided only excluded off-label uses. What do you want in the report: ______All encounters in the database except the excluded off-label uses. ______All encounters in the database, including encounters that contain the off-label uses, with the off-label words and off-label codes redacted from the report. ______Only encounters in the database that include the off-label uses, with the off-label words and off-label codes redacted from the report.
[0110] Whether the program is responding to internal rules (which are typically provided in a lookup table) or external rules provided by the customer in response to questions or other input, the rules govern what data is excluded and how data is excluded. If included items and excluded items are provided by the customer, the excluded instructions will always take precedence over the included instructions. Also, the program must make a decision as to encounter records that do not include either the included items or the excluded items. The most obvious solution would be to exclude such records, but alternatively such records could be entirely included, or, alternatively such records could be included with diagnosis words and codes redacted and/or with medicine words and codes redacted.
[0111] Continuing with the example above, consider encounter 2891. Depending upon internal and external rules, the following embodiments could emerge:
a) One embodiment would be to remove the procedure name/drug name (Eylea) and the drug code (j3490) from the report in worksheets Procedures and Procedure Medications but leave all of the other information in the report. b) Another embodiment would be to remove the diagnosis name (DME) and diagnosis code (362.07) from the report in the Diagnosis worksheet, but leave all the other information in the report. c) Another embodiment would be the remove Encounter 2888 from the report altogether, but leave all other encounters.
[0115] Consider Encounter 2891. Here we have an encounter with a potential adverse (stroke) event associated with a medication.
a) One embodiment would be to remove the diagnosis name (stroke) and diagnosis code (436) from the report in the Diagnosis worksheet, but leave all the other information in the report. b) Another embodiment would be to remove Encounter 2891 from the report altogether, but leave all other encounters. c) Another embodiment would be to remove all medicine names and codes, such as Lucentis and J2778.
[0119] Consider Encounter 4001. Here we have an encounter with a potential adverse event (endophthalmitis) associated with an injection, and also a procedure (intravitreal vancomycin injection) that would reasonably imply that endophthalmitis was present. The following different embodiments could be implemented based on internal or external rules.
a) One embodiment would be to remove the diagnosis (endophthalmitis) and diagnosis code (360) from the report in the Diagnosis worksheet, but leave all the other information in the report. Here we would presume that the presence of the procedure Vancomycin and drug code j3370 would not necessarily signify endophthalmitis was present. This presumption would be implemented by internal or external rules as discussed above. b) Another embodiment would be to remove the procedure name/drug name Vancomycin and drug code j3370 as well as the diagnosis name and diagnosis code from the report, but leave all the other information in the report. c) Another embodiment would be to remove Encounter 4001 from the worksheet altogether and leave the remainder of the encounters in the report. d) Another embodiment would be to remove clinical exam findings from the worksheet PatientEncounterFindings that would indicate an adverse event like endophthalmitis. For example, we might remove the word “hypopyon” in the Anteror Segment/Anterior Chamber OD findings for encounter 4001.
[0124] In considering the inclusion and exclusion rules discussed above, it is important to observe that the presence of exclusion data may cause the exclusion of something other than the exclusion data. For example, a rule may provide that if exclusion data is present, then the inclusion data must be excluded. For example, assume that the inclusion data is a list of medicine identifiers (names and codes) and the exclusion data is a list of diagnosis identifiers (names and codes). The rule may provide that if a particular encounter includes an excluded diagnosis identifiers, then the medicine identifiers are excluded. That is, the medicine identifiers may be redacted or the entire encounter record could be excluded.
[0125] Likewise, rules may exclude data based on two sets of inclusion data. For example, first and second sets of inclusion data may be provided. A rule may provide that if an encounter included data from the first set of inclusion data is present, but did not include data from the second set of exclusion data, then something must be excluded. For example, assume that the first set of inclusion data is a list of medicine identifiers (names and codes) and the second set of inclusion data is a list of diagnosis identifiers (names and codes). The rule may provide that if a particular encounter includes one of the medicine identifiers from the first set but does not include one of diagnosis identifiers from the second set, then the medicine identifiers are excluded. That is, the medicine identifiers may be redacted or the entire encounter record could be excluded.
[0126] As will be appreciated from the discussion above, the various embodiments of the present invention are primarily concerned with the exclusion of data rather than the inclusion of data. By excluding data the customer is protected from data that he should not view. The exclusion of data can be accomplished automatically with little or no input from the customer, or the customer can participate in the exclusion of data by answering either general questions or detailed questions depending on the customer's preference. Although various embodiments have been disclosed above as examples, it is understood that the embodiments are not intended as limitations on the invention. It is understood that the invention is capable of numerous rearrangements, modifications and substitutions of steps without departing from the spirit of the invention as set forth in the appended claims. | Medical records are created and modified based upon the needs of the user. In addition to selecting information needed by a user from a database, the present invention identifies and eliminates information from the medical records that is not needed or wanted. A computer database is created by receiving from healthcare providers a plurality of electronic encounter records. The computer further receives input data relating to the medical information that the customer wishes to include in the desired report. The input data may include items to be included in the report or items to be excluded from the report. The computer analyzes the patient encounter records in the database to identify and select a subset of patient encounter records based on the input data. The computer analyzes the subset of patient encounter records to identify and remove medical information to thereby create a sub-subset of medical information again based on the input data provided by the customer. A desired report is computer generated from the patient encounter records based on the sub-subset of medical information. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an apparatus and process for the manufacture of dimensionally accurate die-formed parts.
2. Background Information
U.S. Pat. No. 4,270,890 corresponding to German Patent No. 29 24 704 discloses a device for controlling the height of die-formed parts made from powder material by measuring the distances between the moving die parts and parts or elements fixed to the press frame. In this manner, the thickness of the pressings is measured and compared with the desired size to assume uniformity in dimension of the die formed parts. It is well known in die-forming of parts that the pressures generated create deformation in the press frame, altering the relative distances between the die parts. When the measuring elements are fixed to the press frame, then deformations of the press frame during the pressing will effect the readings produced by the measuring resulting in deviations in the desired height of the die-formed parts. In U.S. Pat. No. 4,270,890, it is disclosed that the measuring elements are fixed in relation to the press and, therefore, are not subject to the effects of any stretching of the press frame produced by high pressing forces.
The more stringent the requirements for precision geometry on a die-formed part, the smaller the tolerances. Consequently, any disruption caused by the elastic deformation of the pressure rams during the pressing process will effect the readings produced by the measuring and accuracy of the die-formed part. For simple die-formed parts (e.g. a cylindrical shape), this effect is insignificant, since the die tools are so rigidly constructed that no significant elastic deformations occur in the range of the pressing force encountered. On more complicated parts with several offsets, as utilized in multi-plate adaptor dies disclosed in German Patent No. 31 42 126 C2, the elastic deformation of the rams can not be ignored. Such die tools have a relatively thin-walled, long and slender shape and not a substantially rigid construction. This type of die tool configuration is subject to significant elastic deformation due to stretching of the press frame, under the action of the pressing force.
OBJECT OF THE INVENTION
An object of the invention is to provide a process and apparatus for improving the precision in the geometry of die-formed parts and, particularly, die-formed parts having offsets on several different levels.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a process for manufacturing die-formed parts by compressing powder material between pressing faces of rams of a press that includes the steps of positioning a powder material between oppositely positioned pressing faces of the rams. The rams are supported for longitudinal movement toward and away from each other. Pressure is applied to the rams to advance the rams to a preselected die-forming position where the pressing faces are positioned a preselected distance apart to achieve a desired configuration for the die-formed part. Each ram is monitored for a change in the shape in the ram due to elastic deformation incurred in the pressing operation. The position of the pressing face of each ram is compared with a predetermined position for desired configuration of the die-formed part after each pressing cycle. The pressure applied to each ram is adjusted in response to the detection of elastic deformation in the ram to advance the ram pressing face to a position required to achieve the desired configuration for the die-formed part.
In addition, the present invention is directed to apparatus for making die-formed parts from powder material that includes a press frame having a plurality of movable press components each having a pressing surface. A first press component and a second press component are supported in the press frame for movement toward and away from each other. Power means advances the first and second press components to a limit position spaced a preselected distance apart for compressing powder material positioned therebetween into a preselected configuration for a die-formed part. Means is provided for recording the relative distance between the pressing surfaces of the first and second press components in the limit position. Transducer means on the first and second press components detect elastic deformation in the press components. Controller means connected to the transducer means and the power means receives an input signal from the transducer means to detect elastic deformation and transmit an output signal to actuate the power means to advance the press components. The power means in response to the output signal advances a selected one of the press components a distance proportional to the magnitude of the elastic deformation to compensate for a change in the distance between the pressing components and form the die-formed part having the desired configuration.
Further, in accordance with the present invention there is provided a process for the manufacture of dimensionally accurate die-formed parts from powder compounds on a press in a die that includes a top ram and a bottom ram supported by components in the press. The position of the components supporting the rams is measured relative to a fixed point. The components supporting the rams are moved to a specified position in relationship to one another. The relative positions of the top and bottom rams in the press limit position are measured. The position of at least one of the rams is corrected by movement of the component supporting the ram in the pressing direction to a distance corresponding to a change in the dimension in the ram as a result of elastic deformation experienced by the ram.
The present invention, in overcoming the problem unresolved by the above-described prior art device, provides in a die-forming process a distance measurement system for determinating the position of a pressure ram installed in the immediate vicinity of the pressing surface of the ram. With this arrangement, measurements are taken at the pressing surface to provide a more accurate reading of the distance between the moving and fixed die parts than available when the measuring system is supported by the press frame which is subject to deformation. Consequently, elastic ram deformations do not effect the measuring system of the present invention. For structural reasons, however, it is generally impossible to fasten the distance measurement system in this manner.
In accordance with the present invention, the elastic deformation of the pressure rams are detected by direct or indirect measurement of the pressing force. The relative position of the opposite pressure ram in the pressing limit position is corrected as a function of the deformation values determined. The specified positions of the components supporting the rams, to which the moving parts of the length measurement system are fastened, are preliminary values. The values are based on the geometry of the die-formed part to be produced, taking into consideration the length of each individual ram. The specified positions of the components are corrected such as by moving the pressing surfaces of the top and bottom rams closer together or farther apart approximately by the amount of the stronger or weaker elastic deflection of the pressure rams caused by the pressing force. The correction values are calculated, for example, on the basis of the spring characteristic of the pressure rams as determined in preliminary tests and the pressing force measured during the pressing. It is not absolutely necessary to perform this correction for all rams. For example, on a multi-ram tool, the rams are relatively short and/or thick-walled and remain in their original specified position because the rams experience negligible elastic deformation. Consequently, only a ram with a less-rigid spring characteristic requires a correction in its relative specified position.
Another feature of the present invention includes production of die-formed parts in accordance with precise tolerances even when the die parts are subject to severe fluctuations in the pressing forces which generate elastic deformation of the pressure rams during the production, such fluctuations being caused, for example, by changes in the pressability of the powder used.
The invention is explained in greater detail below with reference to the simple embodiment illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary sectional view in side elevation of a press for making die-formed parts.
FIG. 2 is a diagrammatic illustration of an electronic control system for measuring deformation of the press parts and correcting the positions of the press parts in response to deformation.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings and, particularly to FIGS. 1 and 2, there is illustrated a press tool of a press used in the manufacture of die-formed parts from steel powder, such as a ring-shaped, die-formed part 1. The die-formed part 1 is surrounded by a jacket-shaped die 2. The die-formed part 1, for example, has elevations 1A, 1B, and 1C as seen in cross-section in FIG. 1. The press includes a plurality of rams 3, 4, 5 corresponding to the elevations formed on the die-formed part 1. The rams 3, 4, 5 are independently movable relative to one another. The rams 3, 4, 5 are co-axially guided for movement toward and away from ram 6 which receives the powder material forming part 1. The surfaces of the rams 3, 4, 5 opposite the powder material are positioned at different elevations to form the stepped underside of the die-formed part 1. The opposite or smooth upper surface of the die-formed part 1 is formed by the top ram 6.
To achieve a precise geometry or configuration, the die-formed part 1, in the limit position of the press as shown in FIG. 1, the distances between the pressing surfaces 6A of ram 6 and the pressing surfaces 3A, 4A, 5A of rams 3, 4, 5 must be precisely set to form the corresponding elevations of the die-formed part having the preselected heights 1A, 1B, and 1C. The relative distances between the pressing surface 6A and pressing surfaces 3A, 4A, 5A are measured after each pressing operation or cycle. The relative positions of the rams 3, 4, 5, and 6 are indicated by a distance measurement system shown in FIG. 1. The measurement system includes a measuring grid 7 and indicators or reference points 8, 9, 10 which are movable on the grid 7 with respect to a fixed datum or zero point P. The measuring grid 7 is rigidly connected to the press component 11 which supports the press ram 5. The indicators 8, 9, 10 are connected to press components 12, 13, 14 which support ram 6 and rams 3 and 4, respectively of the press. The press components 12, 13, 14 advance and retract the support rams 6, 3, and 4 by operation of the press drive mechanism. The indicators 8, 9, 10 move with the rams 6, 3, 4.
The distances of the pressing surface 6A from the pressing surfaces 3A, 4A, and 5A are initially determined for the desired geometry of die part 1. Also the distances of the movable reference points 8, 9, and 10 from the pressing surfaces 6A, 3A, and 4A respectively are known. In addition, the distance of the ram pressing surface 5A from the datum point P is initially known for the desired die-part configuration. With this arrangement, the desired positions of the indicators 8, 9 and 10 from datum point P for a preselected configuration of die-part 1 as determined by the distances of ram pressing surfaces 3A, 4A, 5A from ram pressing surface 6A are selected.
The relative positions of the rams 3, 4, 5 to ram 6 set the elevations 1A, 1B, and 1C of the die-formed part 1 or configuration of the die-formed part 1. However, these measurements are only a preliminary indication of the relative positions of rams 3, 4, 5 and 6 prior to being subjected to elastic deformation as a result of the die-forming operation. While the rams 3, 4, 5 and 6 are rigid members, they possess spring characteristics resulting in elastic deformation of the rams as a result of the pressure forces applied thereto during the die-forming operation. Elastic deformation of the rams changes the relative positioning of the rams which in turn changes the configuration of the die-part. Consequently, the relative positioning of the rams must be continuously monitored. Adjustments must be made in the position of the rams to maintain uniformity in the shape of the die-part for each pressing cycle. The adjustments made are based on the recorded elastic deformation of the rams.
In one example of the present invention, as seen in FIG. 1, the ram 6 is relatively short in length with a substantial body mass. Consequently, ram 6 experiences little or no elastic deformation. On the other hand, rams 3, 4, 5 having an elongated body mass and comparatively thin walls are subject to the effects of elastic deformation. In particular, the ram 5 which surrounds a mandrel 15 is an elongated, thin-walled structure, making the ram 5 readily susceptible to elastic deformation.
The detection of elastic deformation, such as a change in length of the rams 3, 4, 5, is accomplished with the above-described measurement system and an electric control system 16 shown in FIG. 2. The control system 16 includes a plurality of force transducers 17, 18, 19 of a transducer control 20. Transducers 17, 18, 19 are connected to the rams 3, 4, 5 respectively as shown in FIG. 1. The transducers 17, 18, 19 are operable to detect displacement of the rams due to elastic deformation in response to the forces applied to the rams in the pressing operation. Force transducers suitable for use in the present invention, include piezoelectric sensors, strain gauges and the like.
Transducers or strain gauges 17, 18, 19 are electrically connected as illustrated in FIG. 2 through transducer control 20 to a power source 21 and a controller 22, such as a microprocessor. The controller 22 is, in turn, connected to a readout device 23 that provides a quantitative measurement of the change in the dimension, such as length, of each ram subjected to elastic deformation.
In operation, when the strain gauges 17, 18, or 19 record strain applied to the respective rams 3, 4, 5 resulting in elastic deformation of the ram during the pressing cycle, an output signal is transmitted to the transducer control 20. A responsive signal for the respective strain gauge/ram is supplied to controller 22. The controller 22 being programmed with the specification of each ram calculates in accordance with known formulas the amount of deformation corresponding to the strain gauge reading. This can also be accomplished by reference to tables that convert strain gauge readings to deformation measurements. Accordingly, controller 22 actuates readout device 23 to provide a numerical indication of the deformation for each strain gauge reading as a result of the elastic deformation experienced by each ram.
In one example, in the event the readout device 23 indicates a deformation of 0.25 mm for ram 3 in a pressing cycle. The press component 13 is advanced an additional increment of 0.25 mm as indicated by indicator 9 on measuring grid 7. Thus, the ram 3 is advanced from its initial position shown in FIG. 1 a distance of 0.25 mm toward ram 6. The ram advancement is accomplished by actuation of press component 13. Similar adjustments are made in the positioning of rams 4 and 5 based on the deformation amount recorded by the strain gauges 18 and 19, calculated by controller 22, and recorded by readout device 23.
It should be understood that in accordance with the present invention the electronic control 16 may be connected in an integrated circuit with the press components 12, 13, and 14 to automatically adjust the position of the rams in response to recorded deformation. A feedback circuit can be employed in the integrated circuit to continuously adjust the ram positions to achieve the desired configuration of the die-formed part.
Once the magnitude of deformation or change in length of rams 3, 4, 6 is determined, the press components associated with the rams are actuated to move the rams to a desired limit position where the powder material is compressed into the desired shape for forming the die-formed part 1 having a graduated surface structure. The rams 3, 4, and 5 are thus advanced to the required limit positions shown in FIG. 1 during each pressing cycle to form the part having the desired configuration which configuration is precisely repeated after each pressing operation by virtue of the process for monitoring ram elastic deformation and making the necessary adjustments in the positioning of the rams.
The predetermined or limit position of the rams to achieve the desired shape of the die-formed part 1 is shown in FIG. 1. The relative position of each ram must be precisely controlled to assure uniformity in the shape of the die-formed part after each pressing operation. However, elastic deformation in the rams as a result of the forces encountered in the pressing operation distorts the rams. The present invention overcomes the errors which would occur in the die-forming process if the ram elastic deformation were not taken into consideration.
With the present invention, distortion of the rams due to elastic deformation encountered during the pressing operation is detected by the individual transducers 17, 18, 19. Distortion of the rams alters the limit position of the rams pressing surface, i.e. the relative distances of the surfaces 3A, 4A, 5A from surface 6A differ from the desired distance. Each transducer 17, 18, 19 detects the strain associated with the elastic deformation which occurs in the ram. Based on the magnitude of the elastic deformation that occurs in any one of the rams 3, 4, 5, the press is actuated to adjust the pressure applied to the respective ram and change its relative position in the final or limit position. For example, elastic deformation of the rams 3, 4, 5 requires an advance of the ram pressing surfaces 3A, 4A, 5A to a new position as indicated by the measuring grid 7. The pressing surfaces 3A, 4A, 5A are advanced to a position relative to the pressing surface 6A to form the die part having a configuration corresponding exactly to the required configuration of the part as illustrated in FIG. 1 having elevations at a required height.
The force transducers 17, 18, 19 are responsive to elastic deformation experienced by each ram. Accordingly, each ram position is continuously monitored during each cycle of the pressing operation. Thus, in the even of elastic deformation occurring in any one of the rams, the relative position of the distorted ram to achieve the desired part shape is altered by the degree of the elastic deformation.
Generally, corrections required to be made to the relative positioning of the rams are made in the next successive pressing cycle. As a rule this provides satisfactory adjustment to the ram position to assure precise geometry of the die-formed part where a variation of the shape of the ram may be very slight. In this manner, minimal adjustments are made without requiring a substantial adjustment to be made from one pressing cycle to another. By constantly monitoring the effect of the pressing forces on the rams to compensate for elastic deformations a uniformity in the configuration of the die-formed part is obtained for each successive cycle.
In summary, one feature of the invention resides broadly in a process for the manufacture of dimensionally-accurate die-formed parts from powder compounds, in particular from metal compounds, on a press in a die, under the action of at least one bottom ram and one top ram, whereby the position of the components supporting the ram(s) and/or the die is measured relative to a fixed point, and the components supporting the ram are moved into a specified position in relation to one another which, taking the ram lengths into considerations, corresponds to the specified dimensions of the die-formed part in the pressing direction, characterized by the fact that in the press limit position, the specified position of at least one of the components supporting the rams is corrected in the pressing direction by an amount which corresponds to the elastic deformation of the ram or rams as a result of the action of the pressing force.
Another feature of the invention resides broadly in a process characterized by the fact that the pressing force is measured on at least one of the rams during the pressing cycle, and is used to calculate the corrected specified position in the same pressing cycle.
Yet another feature of the invention resides broadly in a press for the performance of the process with a die 2 with a least one top ram 6 and bottom rams 3, 4, 5 which can be moved relative to one another, with measurement equipment 7, 8, 9, 10 for the determination of the position of components 11, 12, 13, 14 supporting the rams 3, 4, 5, 6 which can be moved by force devices, and with an electronic regulation and control system connected to it to move the components 11, 12, 13, 14 supporting the ram 3, 4, 5, 6, and with at least one measurement apparatus connected to the electronic control for the direct or indirect measurement of the pressing force on at least one of the rams 3, 4, 5, 6, characterized by the fact that correction values for the elastic deformation of the ram or rams 3, 4, 5, 6 caused by the pressing force can be called up, or can be calculated on the basis of the spring characteristic of the ram 3, 4, 5, 6 in question.
A further feature of the invention resides broadly in a press characterized by the fact that the measurement apparatus is a piezoelectric sensor or a strain.
All, or substantially all, of the components and methods of the various embodiments may be used with at least one embodiment or all of the embodiments, if any, described herein.
All of the patents, patent applications, and publications recited herein, if any, are hereby incorporated by reference as if set forth in their entirety herein.
The details in the patents, patent applications, and publications may be considered to be incorporable, at applicant's option, into the claims during prosecution as further limitations in the claims to patentably distinguish any amended claims from any applied prior art.
The invention as described hereinabove in the context of the preferred embodiments is not to be taken as limited to all of the provided details thereof, since modifications and variations thereof may be made without departing from the spirit and scope of the invention. | A plurality of rams in a pressing machine are movable into and out of a predetermined position to compress power material and shape a die-formed part. The rams are advanced to a pre-selected spaced relationship to form a desired configuration of the die-formed part. Strain gauges are mounted on each ram to detect during the pressing operation elastic deformation, altering the dimension of the ram and the shape of the die-formed part. In response to detected elastic deformation, the strain gauges transmit a signal through a controller to a readout device for recording the magnitude of ram deformation. Thereafter, the press drive mechanism is actuated to move the rams to compensate for the change in dimension of the rams so that the rams are repositioned to maintain the desired spaced relationship for a predetermined configuration of the die-formed part. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a level control of a road vehicle, in particular, to the adjustment of a vehicle level within a given range by detecting the relative height between the axle and the frame of a carrosserie by means of a level detector and controlling a hydraulic pressure supplied to a suspension system in accordance with the detected height.
An example of the level adjustment of the kind described is disclosed in U.S. Pat. No. 4,105,216 (issued Aug. 8, 1978, Class 280), for example, in which a level detector detects a range of vehicle level, and the detected signal is processed in a signal processing circuit to derive a signal which energizes a levelling drive system. The signal is applied to a level control circuit which causes a hydraulic pressure supplied to a suspension system to be reduced if the vehicle level is determined to be "high" and causes the hydraulic pressure to be increased if the vehicle level is determined to be "low". In order to prevent a repetitive operation to reduce or increase the hydraulic pressure which would occur as the detected vehicle level oscillates adjacent to the boundary between "medium" and "high" or between "medium" and "low" region, the level control circuit includes a set of leading end delay circuits in each of "high" and "low" level signal processing loops.
The levelling drive system is energized to lower or raise the vehicle height at a given time interval after the detection of the vehicle height in either high or low region, respectively. If the vehicle level is determined to be in the medium region, the levelling drive system is immediately deenergized. Therefore, there is a tendency for the vehicle level to be settled in the medium region adjacent to the boundary with the high or the low region, resulting in a large deviation which is obtained in the settled level of the vehicle. In addition, the frequency of the energization or deenergization of the levelling drive system increases.
SUMMARY OF THE INVENTION
It is a first object of the invention to lessen the repetition of the energization or deenergization of the vehicle level adjustment, and a second object is to reduce a deviation between the levels where the vehicle height is settled.
The above objects are accomplished in accordance with the invention by providing a vehicle level detector which is capable of producing a signal which distinguishes between vehicle levels in at least "high", "medium high", "medium low" and "low" regions. In response to the level detection signal, which indicates a vehicle level in the "high" region, a level lowering command signal is produced and is maintained until a vehicle in the "medium low" region is reached. The lowering command signal causes a drive system associated with a suspension system to be energized to lower the vehicle level. On the contrary, if the signal indicates a vehicle level in the "low" region, a level raising command signal is produced and is maintained until a vehicle level in the "medium high" region is reached. The raising command signal energizes the drive system to lower the vehicle level. In this manner, the energization to lower or raise the vehicle level is initiated in response to the detection of a vehicle level in either the "high" or the "low" region, and the deenergization occurs at a target which is defined by the boundary between the "medium low" and the "medium high" region of the vehicle level. In this manner, a level lowering and raising operation involves a hysteresis. Accordingly, the operation can be summarized as aiming at a single point, which is the boundary between the "medium low" and the "medium high" region, minimizing a deviation in the vehicle level achieved. Nevertheless, the frequency of energization and deenergization is reduced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1a is a schematic side elevation of a vehicle level detector used in an embodiment of the invention;
FIG. 1b is a cross section of the detector;
FIGS. 1c, 1d, 1e and 1f are cross sections taken along the line I--I shown in FIG. 1b, illustrating different operative conditions;
FIG. 2a is a block diagram of an embodiment of the invention;
FIG. 2b is a chart illustrating various conditions of signals appearing in various parts of the embodiment;
FIG. 3a is a block diagram of another embodiment of the invention; and
FIG. 3b is a flow chart illustrating a sequence of operations of the embodiment shown in FIG. 3a.
DESCRIPTION OF EMBODIMENTS
Referring to FIG. 1a, there is shown a vehicle level detector 100 used in an embodiment of the invention, illustrating the manner of mounting the detector on a road vehicle. Specifically, the detector 100 is fixedly connected to the frame 10 of a carroserie and includes a rotary shaft to which one end of a link 20 is coupled. The other end of the link 20 is coupled to an outer casing of a differential gear 30. An axle is shown at 40. The level detector 100 is shown in section in FIG. 1b. The level detector 100 includes a rotary shaft 103, on the free end of which is fixedly mounted a light shield 105 formed with a pair of turnbacks 104a, 104b which are in the form of arcuate segments. The link 20 is fixedly connected to the other end of the shaft 103. The detector includes a base 106 on which is fixedly mounted a printed wiring board 107 which in turn fixedly carries a pair of photosensors 101, 102. FIGS. 1c to 1f show cross sections taken along the line I--I shown in FIG. 1b. FIG. 1c corresponds to a "low" region vehicle level, FIG. 1d to a "medium high" region, FIG. 1e to a "medium low" region and FIG. 1f to a "low" region, respectively. Each of the photosensors 101 and 102 comprises a combination of a light emitting diode and a phototransistor as shown in FIG. 2, which are arranged such that light emitted by the light emitting diode and directed toward the phototransistor is adapted to be intercepted by selected turnbacks 104a, 104b of the light shield 105. The outputs a, b (see FIG. 2a) from the photosensors 101, 102 which depend on the vehicle level is illustrated in a chart shown in FIG. 2b.
Referring to FIG. 2a, which shows an embodiment of the invention, the photosensors 101, 102 of the level detector 100 are connected to a vehicle level adjuster 120 through connectors. The adjuster 120 comprises a signal processor 130 and a level control circuit 140.
The signal processor 130 includes a pair of inverting and amplifying transistors Tr1, Tr2, an inverter IN1, NAND gages NAD1 to NAD3, first and second flipflops FF1, FF2 and NOR gate NOR1. The levels of signals A to F appearing at various points in the circuit arrangement of FIG. 2a which are designated by corresponding letters are indicated in the chart of FIG. 2b in relation to the levels of the inputs a and b. Referring to FIG. 2b for subsequent description, it is initially assumed that the vehicle level has now changed from the "medium high" to the "high" region. Considering the first flipflop FF1, it will be seen that there is no change in the set (S) input D and reset (R) input C, so that this flipflop remains reset. In the second flipflop FF2, the set (S) input E=L and the reset (R) input F=H, so that this flipflop is set to provide a Q output of H level (a level lowering command signal), which causes the output of NOR gate NOR1 to change from its H to its L level, instructing an adjustment of the vehicle level. If the vehicle level subsequently enters the "medium high" region, the set input E=H and the reset input F=H in the second flipflop FF2, which therefore maintains its status unchanged, thus continuing to output the level lowering command signal. However, when the vehicle level enters the "medium low" region, the set input E=H and the reset input F=L in the second flipflop FF2, which therefore reset to change its Q output from the H level (the level lowering command signal) to the L level (interruption of lowering the vehicle level). Thus, the output from NOR gate NOR1 changes from its L to its H level (interruption of adjusting the vehicle level). The flipflop FF1 continues to maintain its reset status. When the vehicle level enters the "low" region, the flipflop FF2 remains reset while the flipflop FF1 is set since the set input D=L and the reset input C=H. Accordingly, its Q output changes to the H level (a level raising command signal), whereby the output from gate NOR1 changes from its H to its L level, instructing an adjustment of the vehicle level. If the vehicle level returns to the "medium low" region subsequently, both the first and the second flipflop FF1, FF2 maintain their previous status (FF1 set and FF2 reset). If the vehicle level then changes to the "medium high" region, the first flipflop FF1 becomes reset since the set input D=H and the reset input C=L. Accordingly, its Q output changes from its H level (level raising command signal) to its L level (interruption of raising the vehicle level), and the output from gate NOR1 changes from its L level (instructing an adjustment of the vehicle level) to its H level (interruption of adjusting the vehicle level).
The level control circuit 140 includes a pulse generator PGE, a counter CO1 acting as a frequency divider, a counter CO2 for introducing a time delay in the energization which is used for adjusting the vehicle level, a third counter CO3 which determines a time limit of energization, AND gates AN1 to AN3, inverters IN2 to IN4 and NOR gate NOR2. The counters CO2 and CO3 assume a cleared condition as long as their CLR inputs remain at the H level, and count up during the time their CLR inputs remain at the L level and CE inputs remain at the H level. When the output from gate NOR1 assumes its L level (instructing an adjustment of the vehicle level), the counter CO2 begins up-counting until a given number of timing pulses, which are Q 10 bit outputs from the counter CO1, have been counted, whereupon its Q 3 bit output assumes an H level. When Q 3 =H, this is inverted by the inverter IN2 before the L level is applied to the terminal CE to interrupt the up-counting operation by the counter CO2. Conversely, in response to the application of Q 3 =H to its CE input terminal, the counter CO3 initiates an up-counting operation and continues it until a given number of timing pulses, which are Q 14 bit outputs from the counter CO1, have been counted, whereupon its Q.sub. 3 bit output assumes an H level. The gate NOR2 receives the output from the inverter IN2 and the Q 3 bit output from the counter CO3, and therefore produces an H output from the time the Q 3 bit output from the counter CO2 assumes an H level until the Q 3 bit output from the counter CO3 assumes an H level. When the Q 3 bit output from the counter CO3 assumes an H level, the output of the gate NOR2 changes to its L level, thereby disabling AND gate AN1 to cease the up-counting operation by the counter CO3. The output from the gate NOR2 is also applied to AND gates AN2 and AN3. The other input of the gate AN2 receives the level raising command signal produced by the signal processor 130 (or the high level Q output of the flipflop FF1) while the other input of the gate AN3 receives the level lowering command signal or the high level Q output from the flipflop FF2. The outputs of the gates AN2 and AN3 are fed through inverters IN3 and IN4, respectively, to an amplifier P-AM of a drive system associated with a suspension system, which comprises the amplifier P-AM, a relief valve 300, a relay 201, a motor 202 and an air compressor 203.
When the vehicle level enters the "high" region, the flipflop FF2 is set in the manner mentioned previously, applying the level lowering command signal H to the gates AN3 and NOR1, allowing the counter CO2 to initiate the up-counting operation. When the count in this counter reaches a given value corresponding to Q 3 , the output of the gate NOR2 changes to an H level which enables an energization. Thereupon the output of the gate AN3 assumes an H level allowing the relief valve 300 to open at a preselected rate to withdraw the air from an air chamber of the suspension system 400. If the vehicle level returns to the "medium low" region before the counter CO2 counts up to the given count corresponding to Q 3 (or a time delay t s of the leading end), the flipflop FF2 is reset to cause the output of the gate NOR1 to resume the H level, whereby the counter CO2 is cleared, thus preventing the output from the gate NOR2 from assuming an H level. Accordingly, if the vehicle level temporarily changes to the "high" region and immediately returns to the "medium low" region as may be caused by oscillations, the relief valve 300 cannot be opened. At a time interval after the output of the gate NOR2 has changed to its H level (which allows the relief valve 300 to open), corresponding to the Q 3 count of the counter CO3, the output of NOR2 changes to the L level to cause the relief valve 300 to be closed if the level lowering command signal continues to be present. Thus, this time interval determines the maximum length of time during which the relief valve 300 is allowed to be opened. The purpose of such an arrangement is to prevent an excessive withdrawal of the air in the event the withdrawal of the air fails to achieve a reduction in the vehicle level due to failure of certain parts or under a very light loading of the vehicle. However, in normal instances, the vehicle level begins to be lowered as the relief valve 300 is opened, and the vehicle level will reach the "medium low" region by the time the counter CO3 completes its up-counting operation to the given number. In this manner, the flipflop FF2 is reset to change the output of the gate AN3 to its L level, thus causing the relief valve 300 to be closed.
When the vehicle level enters the "low" region, the flipflop FF1 is set in the manner mentioned previously, applying the level raising command signal H to both the gate AN2 and the gate NOR1, allowing the counter CO2 to initiate its up-counting operation. When this counter has counted up to a given count corresponding to the Q 3 count, the output of the gate NOR2 assumes the H level which enables an energization. Accordingly, the output of the gate AN2 changes to the H level, closing the relay 201 to energize the motor 202, thus driving the compressor 203. In this manner, a pressurized air is supplied to the air chamber of the suspension system 400. If the vehicle level returns to the "medium high" region by the time the counter CO2 completes its up-counting operation to the Q 3 count or the time delay t s , the flipflop FF1 is reset to change the output of the gate NOR1 to its H level, whereby the counter CO2 is cleared, preventing the output from the gate NOR2 from assuming the H level. In this manner, the compressor 203 cannot be driven if the vehicle level temporarily changes to the "low" region and immediately turns to the "medium high" region as may be caused by oscillations. At a time interval after the output of the gate NOR2 has changed to the H level (which enables the compressor 203 to be driven), the output of the gate NOR2 changes to its L level, interrupting the drive of the compressor 203 if the level raising command signal continues to be present. Thus, this time interval corresponds to the Q 3 count of the counter CO3 and defines the maximum drive time interval for the compressor 203. The purpose of such an arrangement is to prevent the supply of an excessively high air pressure and an overloading of the motor and the compressor in the event an increase in the air pressure fails to increase the vehicle level due to the failure of certain parts or under an excessively high loading of the vehicle. However, in normal instances, the vehicle level will be raised as the compressor 203 is driven, and the vehicle level will enter the "medium high" region by the time the counter CO3 reaches the given count. Thus, the flipflop FF1 is reset to change the output of the gate AN2 to its L level, thus ceasing to drive the compressor 203.
FIG. 3a shows another embodiment of the invention in which the vehicle level adjuster 120 is formed by one chip microcomputer MPU. The MPU includes an ROM (read only memory) which stores programs for controlling the opening/closing of the relief valve 300 and the energization/deenergization of the motor 202 in accordance with the outputs a and b from the level detector 100. A sequence of control operations performed by the MPU based on such program is illustrated by a flow chart in FIG. 3b. In this flow chart, the term "register" and the term "flag" each represent a single memory location of an RAM (rangom access memory) of the MPU. The term "flag set" refer to the storage of a status data while the term "timer" refers to the execution of a programmed timer which counts a preset number of clock pulses or timing pulses.
A control operation by the MPU will be described below with reference to FIG. 3b. Initially the MPU reads input ports 601, 602 (or signals a, b). If these signals indicate a vehicle level in the "high" region, 1 is added to the content of an H register which contains a duration over which the vehicle remains in the "high" region, and the sum is used to update the content of the H register. An output port 612 is cleared for purpose of assurance, and a programmed timer t 0 is executed, and upon time-out, a reference is made to the content of the H register, and if it is equal to or greater than a given value l, an H level is applied to an output port 611 to allow a relief valve 300 to be opened. Also a level lower flag is set, and a level lower limit timer t MH is turned on or set. The H level at the output port 611 and the level lower flag are both cleared or returned to the L level when the vehicle level enters the "medium low" region or upon the time-out of the timer t MH , whichever occurs first. If the content of the H register is less than the value l, the microcomputer returns to reading the input ports. As a result, if the vehicle level changes from the "medium high" to the "high" region, the relief valve 300 is not opened immediately, but is opened only after a vehicle level in the "high" region continues over a period corresponding to lt 0 . The duration lt 0 corresponds to the time interval required for the counter CO2 of the previous embodiment to count up to a given count corresponding to the Q 3 count. Also, t MH corresponds to the time interval required for the counter CO3 to count up to the given count corresponding to the Q 3 count.
If the signals a and b at the input ports 601, 602 indicate a vehicle level in the "low" region, 1 is added to the content of an L register which contains a duration over which the vehicle level remains in the "low" region, and the sum is used to update the L register. The output port 611 is cleared for purpose of assurance, and the programmed timer t 0 is executed. Upon time-out, a reference is made to the content of the L register, and if it is equal to or greater than a given value m, an H level is applied to an output port 612 to allow the compressor 203 to be driven, and also a level raise flag is set. The H level at the output port 612 is cleared or returned to the L level when the vehicle level enters the "medium high" region or upon the time-out of the timer t ML , whichever occurs first. If the content of the L register is less than the given value m, the microcomputer returns to reading the input ports. As a result, if the vehicle level changes from the "medium low" to the "low" region, the compressor 203 is not driven immediately, but is driven only after the vehicle level in the "low" region continues over a time interval of mt 0 . | A vehicle level controller produces a level lowering command signal whenever the sprung mass of a road vehicle is higher than a given trim band and produces a level raising command signal when the sprung mass is below the trim band. The command signal is applied to a levelling system. The trim band is divided into a high (medium high) and low (medium low) regions. A vehicle level detector produces a signal which distinguishes a vehicle level in four different zones including a range higher than the trim band, a medium high region within the trim band, a medium low region within the trim band and a range lower than the trim band. The level lowering and the level raising command signal are withdrawn whenever a signal from the level detector indicates the medium low and high region within the trim band, respectively. | 1 |
FIELD OF THE INVENTION
This invention is related to sand consolidation methods in which wells are treated to bind unconsolidated matter together in the portions of the formation immediately adjacent to the perforations of the well to form a stable, yet fluid permeable barrier around the wellbore and to facilitate production of fluids from the formation, while restraining the movement of sand into the well. Still more particularly, this invention relates to a method of treating particulate matter, such as sand or gravel, to increase the area of coverage to as close to 100% of the surface area of the particles as possible. Currently, in sand consolidation, improved resin systems are available which can better withstand chemicals used in treating wells, however it has been very difficult to achieve complete coverage of the surface area of the sand or other particulates. Any surface area which is not covered detracts from the integrity of the system, because the untreated area constitutes a weak point where the barrier might be more easily compromised.
BACKGROUND OF THE INVENTION
Sand consolidation is a well known term which applies to procedures routinely practiced in the commercial production of petroleum, where wells are treated in order to reduce a problem generally referred to as unconsolidated sand production. When wells are completed in petroleum-containing formations which also contain unconsolidated granular mineral material such as sand or gravel, production of fluids from the formation causes the flow of the particulate matter into the wellbore, which often leads to any of several difficult and expensive problems. Sometimes a well is said to "sand up", meaning the lower portion of the production well becomes filled with sand, after which further production of fluid from the formation becomes difficult or impossible. In other instances, sand production along with the fluid results in passage of granular mineral material into the pump and associated hardware of the producing well, which causes accelerated wear of the mechanical components of the producing oil well. Sustained production of sand sometimes forms a cavity in the formation which destroys the well by causing its collapse. All of these problems are known to exist and many methods have been disclosed in the art and applied in oil fields in order to reduce or eliminate production of unconsolidated sand from a petroleum formation during the course of oil production.
The above-described problems and potential solutions to the problems have been the subject of extensive research by the petroleum industry in the hope of developing techniques which minimize or eliminate the movement of sand particles into the producing well and associated equipment during the course of producing fluids from the formation. One such general approach suggested in the art involves treating the porous, unconsolidated mass sand around the wellbore in order to cement the loose sand grains together, thereby forming a permeable consolidated sand mass which will allow production of fluids but which will restrain the movement of sand particles into the wellbore. The objective of such procedures is to create a permeable barrier or sieve adjacent to the perforations or other openings in the well casing which establish communication between the production formation and the production tubing, which restrains the flow of loose particulate mineral matter such as sand. Another approach involves removing a portion of the formation around the well and packing specially prepared resin-coated granular material into the formation around the wellbore and subsequently causing it to be cemented together.
It is a primary objective of any operable sand consolidation method that a barrier be formed around the wellbore which restrains the movement of sand particles into the well while offering little or no restriction to the flow of fluids, particularly oil, from the formation into the wellbore where it can be pumped to the surface of the earth.
In-situ chemical sand consolidation operations are typically comprised of three basic steps: a preflush, the treatment, and a postflush.
Many materials have been utilized in treatments for consolidating sand in formations adjacent to production of wellbores. One of the more successful agents utilized for this purpose is fluid comprising monomers or oligomers of furfuryl alcohol which can be polymerized in situ to form a solid matrix which binds the sand grains together, while, at the same time, offering superior resistance to high temperatures and to caustic substances which may be encountered in steam flood operations.
A very important aspect of a satisfactory sand consolidation method, which is the focus of the work described in the present invention, is stability of the permeable barrier. The stability would depend to a large extent on how well the sand grains are actually coated with the resin. Once the barrier is formed and the well is placed on production, there will be a substantial continuing flow of fluids through the flow channels within the permeable barrier, and it is important that the barrier last for a significant period of time, e.g. several months and preferably years, without excessive abrasive wear or other deterioration of the consolidation matrix which would allow the particulate matter to once again flow into the wellbore. This is a particularly difficult objective to accomplish in the instance of sand consolidation procedures applied to wells completed in formations subjected to steam flooding or other thermal recovery methods. The production of fluids in steam flooding operations involve higher temperatures and higher pH fluids than are normally encountered in ordinary primary production, and this greatly aggravates the stability problem of sand consolidation procedures.
Several references in the art disclose resin systems with improvements which are targeted to improve the coating of sand grains by the consolidation resin.
In U.S. Pat. No. 4,427,069 there is disclosed a procedure for consolidating sand in a formation adjacent to a wellbore using an oligomer of furfuryl alcohol, in which the catalyst used is a water soluble acidic salt, preferably zirconyl chloride, which is injected in an aqueous solution into the formation prior to the resin containing fluid injection. The salt absorbs on sand grains, and sufficient acidic salt remains adsorbed on the sand grain during the subsequent resin fluid injection stage that adequate polymerization occurs. Although this has been very effective in most difficult situations where sand consolidation procedures are utilized, particularly in connection with thermal flooding such as steam injection procedures, the procedure nevertheless requires a multi-fluid injection procedure which requires more time and is more expensive than would be desirable. Usually a preliminary sand cleaning step is required before injecting the aqueous-catalyst solution in order to remove the naturally-occurring oil film from the sand grains to ensure good catalyst adsorption on the sand. Also, although catalyst mixes with the subsequently injected polymer to a limited degree, usually sufficient to cause polymerization, it is believed that superior performance would result if the catalyst resin mixture could be made more homogenous prior to polymerization, in order to achieve a dense, strong, durable consolidation mass.
In U.S. Pat. No. 4,938,287, incorporated by reference herein in its entirety, there is disclosed a method for consolidating unconsolidated mineral particles including sand in a subterranean petroleum formation penetrated by a well in fluid communication with at least a portion of the formation, comprising introducing an effective amount of preflush into the formation sufficient to invade substantially all of the pore space of the portion of the formation to be consolidated, said preflush fluid comprising an ester which is a solvent for oil residue on the sand grains and also removes at least a portion of water present in the pore spaces of the formation.
There remains in the art a need for a method to promote more complete coverage of the sand grains by the resin compositions. Currently such chemicals as diesel, esters, alcohols and many other organic materials are used in a preflush step preparation for the resin. While these materials do a good job of cleaning the "face" of the sand, they do very little to promote complete coverage of the chemical upon the sand face. In fact, a typical sand grain that has been exposed to an in-situ treatment is only covered over approximately 40% of its surface. The fact that large portions of the grain are uncoated promotes degradation of the consolidation via fluid getting under the resin and "flicking" it off the sand grain. Furthermore, if the resin was applied to provide the sand grain with some protection against alkaline dissolution, it is obvious that any uncoated surface area on the sand grain is still subject to attack.
SUMMARY OF THE INVENTION
This invention concerns an improvement in a method for consolidating sand in subterranean formations penetrated by wells. The sand consolidation methods utilized in my invention include those which employ a monomer or oligomer which undergoes a condensation polymerization in the formation where the sand consolidation is to be achieved. The improvement comprises introducing an effective amount of preflush into the formation comprising 80-20% of a monomer from which the resin is made, or resin, 20-80% ester, and 1-2% coupling agent, and subsequently introducing a sand consolidating fluid into substantially the same portion of the formation as the preflush fluid, said sand consolidating fluid containing a polymerizable compound, a diluent for the polymerizable compound and an acid catalyst capable of causing condensation polymerization of the compound at fluid injection temperatures; and allowing the injected fluid to remain in the formation for a period of time sufficient to accomplish at least partial polymerization of the monomer, forming a permeable consolidated mass.
DETAILED DESCRIPTION OF THE INVENTION
The present invention concerns improvements in sand consolidation methods of the type disclosed in U.S. Pat. Nos. 4,938,287 supra; and 5,010,953; 5,199,490; and 5,199,492, incorporated herein by reference in their entirety, employing a polymerizable monomer or oligomer, a catalyst for the polymerization of the monomer or oligomer, an organic diluent and, in some embodiments an ester such as ethyl or butyl acetate. In the present invention a preflush is introduced which functions to dissolve undesirable oil and residue from the particles while, at the same time, preparing the surface of the particles to accept more consolidating resin.
In the present invention I have found the preflush should preferably comprise a monomer or oligomer from which the resin to be used in the coating stage is made, an ester, and a coupling agent.
In a less preferred embodiment the preflush can comprise solely the monomer or oligomer of the compound from which the resin to be used in the coating step was made.
The preflush contains 20 to 80% ester, preferably 60 to 80%, say about 80%; 80 to 20 % furan, preferably 40 to 20%, say about 20%; and 1 to 5% coupling agent, preferably 1 to 2%, say about 1%.
Monomer
The monomer from which the resin is made which I have found to be preferred in the invention is furfuryl alcohol. Any monomer which will polymerize upon exposure to heat and contact with an acid catalyst can be used in this process; however, furfuryl alcohol (C 4 H 3 OCH 2 O) is the particularly preferred polymerizable monomer. This material has the advantage of being relatively inexpensive and having the characteristics of autopolymerizing on exposure to acid catalyst and forming a thermal setting resin which cures to an insoluble mass which is highly resistant to chemical attack as well as to thermal degradation.
The monomer can also comprise furfural. The choice of monomer, furfuryl alcohol or furfural, may depend upon whether there is a reason to accelerate the polymerization reaction at the sand grain surface. Furfuryl alcohol will accelerate the polymerization reaction because it is much more reactive than the resin. This is because it has approximately 14 times the reactive sites on a mole basis as does the resin. On the other hand, furfural will not accelerate the reaction, because it is not acid catalyzed. One reason why one might want an accelerated set time(use furfuryl alcohol) is when one is working in a high pressure environment and the resin could flow back if it is not rapidly set downhole. One case where one would not wish to accelerate the reaction(use furfural) would be where a proper postflush to restore permeability could not be accomplished if the reaction was accelerated.
Ester
Any low molecular weight hydrocarbon ester may be used in the preflush mixture of the present process. Alkyl acetates having up to six carbons work well. Particularly preferred species are ethyl acetate or butyl acetate, because of their effectiveness, low cost, and wide-spread availability.
Coupling Agents
Coupling agents are discussed in U.S. Pat. Nos. 2,873,181; 3,041,156; 3,098,730; 4,473,671; and 4,539,048, all incorporated herein by reference. There are three major types of coupling agents of particular interest herein: silanes, titanates, and zircoaluminates. Silanes are by far the most readily available and widely studied. Useable silane coupling agents generally correspond to the formula: X 3 SiR 1 Y, wherein:
R 1 is an alkyl group,
Y is an organofunctional group; and
X is a hydrolyzable group.
Silane coupling agents are discussed in U.S. Pat. No. 3,079,361; incorporated herein by reference. The organofunctional group (Y) may be any of the variety of groups which can react with the resinous adhesive during curing, or which are otherwise sufficiently compatible with the resinous adhesive to form an bonding-like association therewith. Organofunctional groups which function as Y include: amino-, epoxy-, vinyl-, methacryloxy-, mercapto-, ureido- and methacrylate-groups. Examples of silane coupling agents are described in Plueddmann, Silane Coupling Agents, Plemum Press, New York (1982), incorporated herein by reference.
The exact nature of the bonding or association between the hydrolyzable group (X) and the inorganic filler is not fully understood, and may differ for various fillers. For fillers that contain silica, it may be theorized that an Si--O--Si linkage occurs, via reaction of the hydrolyzable group from the coupling agent with a hydroxyl group on the inorganic filler surface. It will be understood that the particular nature of the associative interaction is not critical, to the invention, and it is not intended that the present invention be limited to any particular theory, or type, of interaction. It is noted, however, that the nature of the associative interaction will tend to affect performance and processing.
The hydrolyzable group(s) on the silane can be any of a variety of hydrolyzable groups. The term "hydrolyzable group" and variants thereof, is meant to refer, for example, to any moiety which may be bonded to silicon through a silicon-halogen bond, a silicon-oxygen bond, a silicon-nitrogen bond or a silicon-sulfur bond. Specific examples of hydrolyzable silanes are those in which X is: a halogen, such as chlorine, bromine, or iodine; --OR, where R is a monovalent hydrocarbon or a monovalent halohydrocarbon radical such as a methyl-, ethyl-, octadecyl-, vinyl-, allyl-, hexenyl-, cyclohexyl-, cyclopentyl-, phenyl-, tolyl-, xylyl-, benzyl-, chloroethyl-, trifluoropropyl-, chlorophenyl-, bromocyclohexyl-, iodonaphthyl-, or chlorovinyl-group; --OR where R is a hydroxyhydrocarbon radical such as betahydroxyethyl-, beta-hydroxylpropyl-, omega-hydroxyoctandecyl-, para-hydroxypyhenyl-, hydroxycyclohexyl or beta-gamma dihydroxypropyl-; --OR where R is an etherated hydrocarbon or halohydrocarbon radical having the formula OR 2 ) z OW, where R 2 is hydrocarbon or halohydrocarbon and W is hydrocarbon or H, such as those derived from polyethylene glycols or polypropylene glycols and their monohydrocarbon ethers, and in which z is an integer such as 2, 5, 8 or 10 or, those derived from halogenated glycols such as chloropropylene glycol; or, amino radicals in which the nitrogen is bonded to the silicon, for example as dimethylamino-, methylamino- compounds; and sulfonated radicals containing the Si--S bond such as --SH or --SR compounds, where R is a monovalent organic radical such as a methyl-, ethyl-, or chlorobutyl-group, etc.
There is no requirement that all groups X in X 3 SiR 1 Y compounds be the same. Further, mixtures of coupling agents may be used. The silane can be monomeric material, that is a silane in which all groups X are monovalent radicals; or the silane may be a polymeric material, that is a silane in which at least one group X is a polyvalent radical. Thus, for example, the silane can be in form of a silazane in which the silicons are bonded through nitrogen atoms and each silicon has one beta-(vinylphenyl)ethyl group attached thereto. The silanes can also be polysilthienes in which the silicons are bonded through sulfur atoms and each silicon has a beta-(vinylphenyl) ethyl radical attached thereto.
A second class of coupling agents which can be used in the present invention comprises titanates, which are described generally by the formula:
(RO)m--Ti--(OXR.sup.1 Y)n
Generally, an RO group will couple to the filler, and an (OXR 1 Y) group couples to the organic resin. For typical applications: R is a hydrocarbyl radical or a hydrocarbyl radical substituted with inert substituents such as a halogen, oxygen, sulfur, and phosphorous. Preferably R is a C1- to C10-hydrocarbyl radical, preferably an alkyl- or alkenyl-radical, and most preferably R is a C1 to C4 alkyl-radical such as methyl- or isopropyl-radical; X is an organic binder function group and is selected such that it becomes a permanent part of the polymer network after the resinous adhesive is set. For example, X is preferably a divalent phosphato-, pyrophosphato-, or sulfyl-group; R 1 is a thermoplastic functional group selected such that it is compatible with thermoplastic resins or thermosetting resins. R 1 typically includes a long carbon chain which provides for Van der Waals entanglements. Preferably R 1 is a hydrocarbyl radical or a hydrocarbyl radical substituted with an inert substituent such as those listed above as inert substituents, e.g., a C1 l to C100 alkylene radical; Y is a thermoset functional group selected such that it becomes a permanent part of the polymer network after the resinous adhesive polymerizes. Y typically contains methacrylate or amine and m+n</=7.
Preferably m is 1 and n is 5. It is also noted that R, R 1 , Y and X can each represent a plurality of different radicals in the same titanate coupling agent. The above coupling agents may terminate at the end of the R or R<1> groups with a reactive radical such as an acrylate, methacrylate or vinyl radical.
Usable titanate coupling agents are identified in U.S. Pat. No. 4,473,671, incorporated herein by reference. Specific examples include: isopropyl triisostearoyl titanate, isopropyl tri(lauryl-myristyl) titanate, isopropyl isostearoyl dimethylacryl titanate; isopropyl tri(dodecyl-benzenesulfonyl) titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(diisooctyl phosphate) tri(dioctypyrophosphato) titanate; and isopropyl triacroyl titanate.
A third class of coupling agents which can be employed in the present invention comprises zircoaluminates, which are described generally by the formula:
Al.sub.2 (OR.sup.1 0)aAbBc!x OC(R.sup.2)O!y ZrAdBe!z
Such compounds are discussed in U.S. Pat. No. 4,539,048; incorporated herein by reference. In general: the Al 2 (OR 1 O)a A b B c! groups are chelated aluminum moieties, the OC(R 2 )O! group is an organofunctional ligand, and the ZrA d B e! groups are zirconium oxyhalide moieties. Typically, the organofunctional ligand is complexed with, and is chemically bound to, the chelated aluminum moiety and the zirconium moiety.
For the aluminum moiety,
A and B are preferably independently: hydroxy groups or a halogen, a, b, and c are preferably numerical values such that 2a+b+c=6, (OR 1 0) is an alpha, beta- or alpha, gamma-glycol group in which R 1 is an alkyl-, alkenyl-, or alkynyl-group having one to six carbon atoms, preferably having 2-3 carbon atoms, or (OR 1 0) is an alpha-hydroxy carboxylic acid residue according to the formula:
OCH(R.sup.3)COOH
Wherein R 3 is H or an alkyl group having from 1 to 4 carbon atoms; R 3 preferably being --H or --CH3.
For the organofunctional moieties, --OC(R 2 )O --, each R 2 is preferably: an alkyl-, alkenyl-, alkynyl- or arylalkyl-carboxylic acid having from 2 to 18 carbon atoms, and preferably from 2 to 6 carbon atoms; an amino functional carboxylic acid having from 2 to 18, and preferably from 2 to 6 carbon atoms; a dibasic carboxylic acid having from 2 to 18, and more preferably from 2 to 6 carbon atoms; an acid anhydride of a dibasic acid having from 2 to 6 carbon atoms, most preferably where both carboxy groups are terminal; a mercapto functional carboxylic acid having from 2 to 18 carbon atoms, and preferably from 2 to 6 carbon atoms; an epoxy functional carboxylic acid having from 2 to 18 and preferably 2 to 6 carbon atoms; or, an acid anhydride of a dibasic acid having from 2 to 18, and preferably 2 to 6 carbon atoms.
An extensive variety of --OC(R 2 )O-- anionic ligands are known and can be used. Examples of specific dibasic anions are: oxalic, malonic, succinic, glutonic, adipic, tartaric, itaconic, maleic, fumaric, phthalic and terphthalic anions. Examples of specific aminofunctional carboxylate anions include the anions of: glycine, alanine, beta-alanine, valine, leucine, isoleucine, phenylalanine, tyrosine, serine, threonine, methionine, cysteine, cystine, proline, hydroxyproline, and, aspartic and glutaric acids. Examples of specific useful monobasic carboxylic acid moieties include the anions of the following carboxylic acids: acetic, propionic, butyric, pentanoic, hexanoic, heptanoic, octanoic, dodecanoic, myristic, palmitic, stearic, isostearic, propenoic, 2-methylpropenoic, butenoic, hexenoic, benzoic, and cinnamic.
For the zirconium oxyhalide moiety preferably:
A and B are hydroxy groups or halogens; d and e are numerical values such that d+e=4; the molar ratio of chelated aluminum moiety to zirconium oxyhalide moiety is from about 1.5 to 10; the molar ratio of organofunctional ligand to total metal is from about 0.05 to 2, and preferably about 0.1 to 0.5; and x, y, and z are each at least one.
Application
In applying the process of the present invention, it is desired to inject sufficient preflush material to invade the formation and essentially fill the pore space of the formation from the wellbore extending into the formation for a distance of from 1 to 12 inches.
The quantity of the preflush injected into the formation varies depending on the thickness and porosity of the formation to which the sand consolidation process is to be applied, as well as the diameter of the well and the desired thickness of the permeable barrier in the formation. The thickness and porosity of the formation and the diameter of the well will always be known.
As a general guideline it is sufficient if from 1/8 to 1/2 and preferably from 1/5 to 1/3 gallons of preflush is injected prior to the polymerization chemical, per foot of formation interval being treated with the sand consolidation procedure.
If, for example, it is desire to treat a formation where the thickness is 18 feet and porosity 35% to form a permeable barrier just outside the wellbore which is 8 inches thick, and the well being treated is 10 inches in diameter, then the volume necessary is calculated according to the sample below. It is desired to inject sufficient preflush to fill the pore to the wellbore face and extend twelve inches into the formation. ##EQU1## equals 3.985 cubic feet=29.6 gallons of the consolidating fluid comprising monomer, diluent and acid.
After injection of the preflush the particulates which are sought to be consolidated are cleaned and primed for maximum coverage. Next the resin system is injected. Resin systems or consolidating fluids have been discussed, for example, in U.S. Pat. Nos. 5,010,953; 5,199,492; 4,427,069; 4,938,287; and 5,199,490, all incorporated herein by reference in their entirety.
The resin system preferably comprises 60.0 to 90.0 percent by weight resin in its commercial form, 15 to 30 percent by weight ester, such as butyl acetate, and from 0.01 to 5.0 percent by weight of any acid catalyst, e.g., o-nitrobenzoic acid or toluene sulfonic acid. A preferred method of formulating this solution is to mix the acid with the ester and then mix four parts of the resin emulsion with one part of the mixture of ester and acid.
Any acid known in the art can be used as the catalyst. The preferred internal acid catalyst used to catalyze polymerization of the resin is an oil soluble, very slightly water soluble organic acid. The most preferred acids are o-nitrobenzoic acid or toluene sulfonic acid. From 0.05 to 5.0 and preferably from 1.0 to 4.0 percent by weight of the slightly water soluble organic acid catalyst is incorporated in the resin solution used to coat the particles.
The resin solution and the sand or gravel are mixed together. It is preferred that the volume ratio of sand or gravel to resin solution is from 10 to 30, preferably 15.0 to 25.0. The sand or gravel and resin emulsion are mixed until the particles are thoroughly coated. The appearance and texture of the material produced by the procedure is a wet, tacky mass of coated particles.
A solution is prepared that contains about 80 percent resin and about 19 percent butyl acetate and from 0.8 to 1.2 percent acid catalyst such as o-nitrobenzoic acid or toluene sulfonic acid. Such a solution is used to coat the sand at the surface or in the well. The oil soluble internal catalyst can be mixed with the resin. The catalyst activity is highly dependent on temperature.
Any acid-catalyzed, polymerizable, resinous material which can be used to coat the particles, and then be suspended in the carrier fluid for placement in the formation cavity can be used in the invention. A particularly preferred resin is the furfuryl alcohol oligomer (C 4 H 3 OCH 2 )xH, which is a relatively inexpensive polymerizable resin which autopolymerizes upon exposure to acid catalyst, forming a thermosetting resin, which cures to an insoluble mass highly resistant to chemical attack and thermal degradation. Specifically it is recommended that the resin used be Quacor 1300 Furan Resin marketed by Q. O. Chemical.
It may be desirable to dilute the furfuryl alcohol oligomer with an appropriate solvent such as butyl acetate to decrease viscosity of the fluid such that it can more easily coat the particles.
As the furfuryl alcohol oligomer comes into contact with the acidic catalyst, the action of the heat in the formation and catalyst drives the autopolymerization reaction forward. Thus, the alcohol oligomer polymerizes to a solid mass.
As the polymerization reaction proceeds, water is produced as a by-product. If this water production is allowed to go unchecked, the polymerization reaction will soon equilibrate:
By providing an ester of a weak organic acid in the reaction mixture, the by-product water is consumed in a hydrolysis reaction of the ester to its corresponding alcohol and carboxylic acid. For example, the inclusion of an ester of a weak organic acid, widely available as inexpensive organic solvents, with the polymerizable resin composition serves both as the solvating agent for the polymerizable resin and as an ester to check water production. Accordingly, the polymerization reaction is driven to the desired degree of completion by the uptake of water in the ester hydrolysis reaction.
The amount of resin coated on the sand or gravel particles as a percent of the weight of particulate and resin is from 2 to 10 percent and the catalyst content as a percent of resin is from 1.0 to 5.0 percent. These concentrations can of course be varied depending on individual characteristics of the selected resin and catalyst as well as conditions encountered in the particular application.
The resin, butyl acetate and nitrobenzoic acid, mixture is used to accomplish a thorough coating of the sand grains.
Next, an aqueous saline solution which is from 70% to 100% saturated with inorganic salt, preferably sodium chloride, is injected into the resin saturated zone of the formation. This injection step accomplishes an opening of flow channels within the void spaces in the formation into which the resin catalyst mixture and is injected without removing the polymerizable resin. This would occur with >70% salt solution, which is important to ensure that the resulting polymerized resin bonded sand matrix is sufficiently permeable to permit flow of formation fluids from the formation after the sand consolidation process is completed. The salt water also modifies the resin coating on the sand, and removes water which increases the strength and durability of the polymerized resin matrix.
The well is then shut in for a period of from 1 to 10 days, preferably at least one week. The preferred shut-in period is a function of the formation temperature. This procedure results in the formation of a permeable, durable, consolidated sand mass around the perforations of the wellbore which restrains the movement of sand into the wellbore during production operations, while permitting relatively free flow of formation fluids, particularly formation petroleum, into the wellbore. The thickness of the permeable mass formed around the perforations of the production well casing is determined by the volume of the fluid comprising the polymerizing resin and catalyst injected into the formation.
The following examples are given as specific illustrations of the invention. It should be understood, however, that the invention is not limited to the specific details set forth in the examples.
Experimental Section
To demonstrate the invention a preflush using just butyl acetate was applied. When the butyl acetate preflush was employed, microscopic examination of grains after consolidation revealed the sand grains were approximately 35 to 40% coated. The sand grains were tested by Compressive Strength Testing which is a standard test known to those of ordinary skill in the art.
When a preflush fitting the description of this invention was used the sand grains were approximately 80% coated.
The preflush which was employed comprised 80% butyl acetate, 19% furan resin and 1% silane. This composition did two things. The solvent properties dissolved oil and undesirable materials from the sand grains and the furan resin and coupling agent made it possible for more resin to adhere to the sand grains.
Field Experiment
A producing well is completed in a subterranean petroleum containing formation, the formation being from 2,540 to 2,588 feet. Considerable sand production has been experienced in other wells completed in this formation in the past, and so it is contemplated that some treatment must be applied in order to permit oil production from this formation without experiencing the various problems of unconsolidated and production. This particular well has not been used for oil production, and so little sand has been produced from the formation. It is known that the sand is coated with viscous formation crude, but is otherwise of a reasonable particle size to accommodate sand consolidation process using the natural sand present in the formation. Because of the viscous oil residue on the sand grains, and a significant water saturation in the formation where the consolidation is to be conducted, it is felt that satisfactory sand consolidation results can only be achieved if a preflush is applied to the formation prior to the injection of the polymerizable alcohol.
It is desired to inject sufficient preflush to fill the pore space of a cylindrical portion of the formation adjacent to the wellbore face and extending twelve inches into the formation. The wellbore diameter is ten inches and the porosity is 40 percent. The volume of preflush required is: ##EQU2##
For this purpose about 660 (80%) gallons of butyl acetate, 159 gallons of furan resin and 8.3 gallons of silane were employed.
The sand consolidation fluid is injected into the formation at a rate of 1440 gallons/hour. After the preflush and all of the treating fluid has been injected into the formation, the well is shut in for 6 hours to ensure complete polymerization. At the conclusion of this shut-in period, the well is placed on production and essentially sand-free oil production is obtained.
Although the invention has been described in terms of a series of specific preferred embodiments and illustrative examples which applicants believe to include the best mode known for applying the invention at the time of this application, it will be recognized to those skilled in the art that various modifications may be made to the composition and methods described herein without departing from the true spirit and scope of our invention which is defined more precisely in the claims appended hereinafter below. | A method for consolidating unconsolidated mineral particles in a subterranean petroleum formation penetrated by a well in fluid communication with at least a portion of the formation, including:
a) introducing an effective amount of preflush into the formation sufficient to invade substantially all of the pore spaces of a portion of the formation to be consolidated, said preflush including an ester, and an oligomer or monomer of the compound from which the resin to be used in the consolidation is obtained, an ester, and an effective amount of a coupling agent;
b) introducing a sand consolidating fluid into substantially the same portion of the formation as the preflush fluid, the sand consolidating fluid containing a polymerizable compound, a diluent for the polymerizable compound and an acid catalyst capable of causing condensation polymerization of the compound at fluid injection temperatures; and
c) allowing the injected fluid to remain in the formation for a period of time sufficient to accomplish at least partial polymerization of the monomer, forming a permeable consolidated mass around the wellbore. | 2 |
This is a continuation, of application Ser. No. 08/590,998, filed Jan. 24, 1996, now abandoned.
BACKGROUND OF THE INVENTION
1. Technical Field
The invention is related to plasma reactors for processing semiconductor wafers, and in particular confinement of the processing plasma in the reactor within a limited processing zone.
2. Background Art
Plasma reactors, particularly radio frequency (RF) plasma reactors of the type employed in semiconductor wafer plasma processing in the manufacturing of microelectronic integrated circuits, confine a plasma over a semiconductor wafer in the processing chamber by walls defining a processing chamber. Such an approach for plasma confinement has several inherent problems where employed in plasma reactors for processing semiconductor wafers.
First, the walls confining the plasma are subject to attack from ions in the plasma, typically, for example, by ion bombardment. Such attack can consume the material in the walls or introduce incompatible material from the chamber walls into the plasma process carried out on the wafer, thereby contaminating the process. Such incompatible material may be either the material of the chamber wall itself or may be material (e.g., polymer) previously deposited on the chamber walls during plasma processing, which can flake off or be sputtered off. As one example, if the chamber walls are aluminum and the plasma process to be performed is plasma etching of silicon dioxide, then the material of the chamber wall itself, if sputtered into the plasma, is incompatible with the process and can destroy the integrity of the process.
Second, it is necessary to provide certain openings in the chamber walls and, unfortunately, plasma tends to leak or flow from the chamber through these openings. Such leakage can reduce plasma density near the openings, thereby upsetting the plasma process carried out on the wafer. Also, such leakage can permit the plasma to attack surfaces outside of the chamber interior. As one example of an opening through which plasma can leak from the chamber, a wafer slit valve is conventionally provided in the chamber side wall for inserting the wafer into the chamber and withdrawing the wafer from the chamber. The slit valve must be unobstructed to permit efficient wafer ingress and egress. As another example, a pumping annulus is typically provided, the pumping annulus being an annular volume below the wafer pedestal coupled to a vacuum pump for maintaining a desired chamber pressure. The chamber is coupled to the pumping annulus through a gap between the wafer pedestal periphery and the chamber side wall. The flow of plasma into the pumping annulus permits the plasma to attack the interior surfaces or walls of the pumping annulus. This flow must be unobstructed in order for the vacuum pump to efficiently control the chamber pressure, and therefore the pedestal-to-side wall gap must be free of obstructions.
It is an object of the invention to confine the plasma within the chamber without relying entirely on the chamber walls and in fact to confine the plasma in areas where the chamber walls to not confine the plasma. It is a related object of the invention to prevent plasma from leaking or flowing through openings necessarily provided the chamber walls. It is an auxiliary object to so prevent such plasma leakage without perturbing the plasma processing of the semiconductor wafer.
It is a general object of the invention to shield selected surfaces of the reactor chamber interior from the plasma.
It is a specific object of one embodiment of the invention to shield the interior surface of the reactor pumping annulus from the plasma by preventing plasma from flowing through the gap between the wafer pedestal and the chamber side wall without obstructing free flow of charge-neutral gas through the gap.
It is a specific object of another embodiment of the invention to prevent plasma from flowing through the wafer slit valve in the chamber side wall without obstructing the ingress and egress of the wafer through the wafer slit valve.
SUMMARY OF THE DISCLOSURE
The invention confines the plasma within the chamber without relying entirely on the chamber walls by introducing a magnetic field across an area or plane through which plasma flow is to be stopped. For example, in order to prevent plasma from leaking or flowing through openings necessarily provided the chamber walls, a magnetic field is established at the entrance of the reactor chamber to such an opening, by placing a pair of opposing magnetic poles across the opening, for example. The magnetic field is sufficiently strong to reduce the leakage of plasma to the wall.
In order to prevent the magnetic poles perturbing the plasma processing of the semiconductor wafer, it is preferred that the opposing magnetic poles be part of a closed magnetic circuit. In one embodiment, the poles are opposite ends of a magnet facing each other across the opening. In a preferred embodiment, the opposing poles are on two different magnets, the poles of each magnetic facing the opposing poles of the other magnet, one pair of opposing poles of the two magnets facing each other across the opening through which plasma flow is to be stopped.
In general, the invention can shield a selected surface of the reactor chamber interior from the plasma by imposing a magnetic field across a path travelled by the plasma in reaching that surface.
One embodiment of the invention shields the interior surface of the reactor pumping annulus from the plasma by preventing plasma from flowing through the gap between the wafer pedestal and the chamber side wall without obstructing free flow of charge-neutral gas through the gap by imposing a magnetic field across the gap. In accordance with a first implementation, this field is produced by a pair of ring magnets having juxtaposed opposing circular poles, a pair of which face each other across the pedestal-to-sidewall gap and the other pair of which face each other across the pumping annulus. In accordance with a second implementation, there is only one pair of poles and the two ring magnets are joined as one by a core extending across the pumping annulus. Plural gas passages are provided through the core to permit gas flow through the pumping annulus.
Another embodiment of the invention prevents plasma from flowing through the wafer slit valve in the chamber side wall without obstructing the ingress or egress of the wafer through the valve by imposing a magnetic field across the slit opening of the valve. In accordance with one implementation, this is accomplished by a pair of horseshoe magnets having juxtaposed opposing poles, a pair of which face each other across the slit opening of the valve.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cut-away side view of a plasma reactor in accordance with a first embodiment of the invention employing open magnetic circuits.
FIG. 2 is an enlarged view of the magnetic confinement apparatus near the pedestal-to-side wall gap.
FIG. 3 is an enlarged view of the magnetic confinement apparatus near the wafer slit valve.
FIGS. 4A and 4B correspond to a side view of a plasma reactor in accordance with a preferred embodiment of the invention employing closed magnetic circuits having pairs of opposed magnets.
FIG. 5 is a perspective view of a pair of opposing ring magnets juxtaposed across the pedestal-to-side wall gap.
FIG. 6 is a perspective view of a pair of opposing magnets juxtaposed across the wafer slit valve.
FIG. 7 is a cut-away side view of a plasma reactor in which the closed magnetic circuit is a single magnet whose opposing poles are juxtaposed across the pedestal-to-side wall gap and which are joined by a core extending across the pumping annulus.
FIG. 8 is a top view of the single magnet of FIG. 7 and showing the gas flow holes through the core joining the opposite poles of the magnet.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Conventional Reactor Elements
Referring to FIG. 1, an RF plasma reactor for processing a semiconductor wafer has a vacuum chamber 10 enclosed by a cylindrical side wall 12, a ceiling 14 and a floor 16. A wafer pedestal 18 supports a semiconductor wafer 20 which is to be processed. A plasma precursor gas is injected into the chamber 10 through a gas injector 22 from a gas supply 24. Plasma source power is coupled into the chamber 10 in any one of several ways. For example, the reactor may be a "diode" configuration, in which case RF power is applied across a ceiling electrode 26 and the wafer pedestal 18. This is accomplished by connecting the pedestal 18 and the ceiling electrode 26 to either one of two RF power sources 28, 30. Alternatively, a cylindrical side coil 32 wound around the chamber side wall 12 is connected to an RF power source 34. Alternatively to the foregoing, or in addition thereto, a top coil 36 is connected to an RF power supply. As is conventional, the wafer pedestal 18 may have its own independently controllable RF power supply 28 so that ion bombardment energy at the wafer surface can be controlled independently of plasma density, determined by the RF power applied to the coil 32 or the coil 36.
A vacuum pump 40 is coupled to the chamber 10 through a passage 42 in the floor 16. The annular space between the periphery of the wafer pedestal 18 and the floor 16 forms a pumping annulus 44 through which the vacuum pump 40 evacuates gas from the chamber 10 to maintain a desired processing pressure in the chamber 10. The pumping annulus 44 is coupled to the interior of the chamber 10 through an annular gap 46 between the periphery of the wafer pedestal 18 and the chamber side wall 14. In order for the pump 40 to perform efficiently, the gap 46 is preferably free of obstructions.
A conventional slit valve opening 50 of the type well-known in the art having a long thin opening in the chamber side wall 14 provides ingress and egress for a semiconductor wafer 52 to be placed upon and withdrawn from the wafer pedestal 18.
The walls 12, 14 confining the plasma within the chamber 10 are subject to attack from plasma ions and charged radicals, typically, for example, by ion bombardment. Such attack can consume the material in the walls 12, 14 or introduce incompatible material from the chamber walls 12, 14 into the plasma process carried out on the wafer 52, thereby contaminating the process. Such incompatible material may be either the material of the chamber wall itself or may be material (e.g., polymer) previously deposited on the chamber walls during plasma processing, which can flake off or be sputtered off. Plasma reaching the chamber walls can cause polymer deposition thereon.
The openings from the interior portion of the chamber 10, including the pedestal-to-side wall gap 46 and the slit valve opening 50, permit the plasma to leak or flow from the chamber 10. Such leakage can reduce plasma density near the openings 46, 50, thereby upsetting the plasma process carried out on the wafer 52. Also, such leakage can permit the plasma to attack surfaces outside of the chamber interior. The flow of plasma into the pumping annulus 44 through the gap 46 permits the plasma to attack the interior surfaces or walls of the pumping annulus 44. Thus, the designer must typically take into account not only the materials forming the chamber ceiling 12 and side wall 14, but in addition must also take into account the materials forming the pumping annulus, including the lower portion 56 of the side wall 14, the floor 16 and the bottom peripheral surface 58 of the wafer pedestal 18, which complicates the design. Such a loss of plasma from the chamber 10 also reduces plasma density or requires more plasma source power to maintain a desired plasma density over the wafer 52.
Magnetic Confinement
In order to prevent plasma from flowing from the chamber 10 into the pumping annulus, a magnetic field perpendicular to the plane of the gap 46 and perpendicular to the direction of gas flow through the gap 46 is provided across the gap 46. This is preferably accomplished by providing an opposing pair of magnetic poles 60, 62 juxtaposed in facing relationship across the gap 46. In the embodiment according to FIG. 2, the magnetic pole 60 is the north pole of a magnet 64 located at the periphery of the wafer pedestal 18 while the magnetic pole 62 is the south pole of a magnet 66 next to the inner surface of the side wall 14. The embodiment of FIG. 2 may be regarded as an open magnetic circuit because the returning magnetic field lines of flux 68 in FIG. 2 radiate outwardly as shown in the drawing.
In order to prevent plasma from flowing from the chamber 10 through the slit valve opening 50, a magnetic field perpendicular to the plane of the slit valve opening 50 and perpendicular to the direction of gas flow through the slit valve opening 50 is provided across the slit valve opening 50. This is preferably accomplished by providing an opposing pair of magnetic poles 70, 72 juxtaposed in facing relationship across the slit valve opening 50. In the embodiment according to FIG. 3, the magnetic pole 70 is the north pole of a magnet 74 extending across the bottom edge of the slit valve opening 50 while the magnetic pole 72 is the south pole of a magnet 76 extending along the top edge of the slit valve opening 50. The embodiment of FIG. 3 may also be regarded as an open magnetic circuit because the returning magnetic field lines of flux 78 in FIG. 3 radiate outwardly as shown in the drawing.
One potential problem with the returning lines of magnetic flux 68 (FIG. 2) and 78 (FIG. 3) is that some returning flux lines extend near the wafer 52 and may therefore distort or perturb plasma processing of the wafer 52. In order to minimize or eliminate such a problem, a closed magnetic circuit (one in which returning magnetic lines of flux do not extend into the chamber) is employed to provide the opposing magnetic pole pairs 60, 62 and 70, 72. For example, in the embodiment of FIGS. 4 and 5, the opposing magnetic poles 60, 62 across the gap 44 are each a pole of a respective horseshoe ring magnet 80, 82 concentric with the wafer pedestal 18. The horseshoe ring magnet 80 has the north pole 60 and a south pole 81 while the horseshoe ring magnet has the south pole 62 and a north pole 83. The poles 60, 81 of the inner horseshoe ring magnet 80 are annuli connected at their inner radii by a magnetic cylindrical core annulus 85. Similarly, the poles 62, 83 of the outer horseshoe ring magnet 82 are annuli connected at their outer radii by a magnetic cylindrical core annulus 86. The magnetic circuit consisting of the inner and outer horseshoe ring magnets 80, 82 is a closed circuit because the lines of magnetic flux between the opposing pole pairs 60, 62 and 81, 83 extend straight between the poles and, generally, do not curve outwardly, at least not to the extent of the outwardly curving returning lines of flux 68, 78 of FIGS. 2 and 3.
In the embodiment of FIGS. 4A, 4B and 6, the opposing magnetic poles 70, 72 across the slit valve opening 50 are each a pole of a respective long horseshoe magnet 90, 92 extending along the length of the slit valve opening 50, the long horseshoe magnet 90 extends along the top boundary of the slit valve opening 50 while the other horseshoe magnet extends along bottom edge of the slit valve opening 50.
The advantage of the closed magnetic circuit embodiment of FIG. 4 is that the magnetic field confining the plasma does not tend to interfere with plasma processing on the wafer surface.
In the embodiment of FIGS. 7 and 8, the lower annuli 81, 83 of the two horseshoe ring magnets 80, 82 are joined together as a single annulus by a magnetic core annulus 96, so that the horseshoe ring magnets 80, 82 constitute a single horseshoe ring magnet 94 having a north pole 60 and a south pole 62. The core annulus 96 extends across the pumping annulus 44 and can be protected by a protective coating 98 such as silicon nitride. In order to allow gas to pass through the pumping annulus 44, the core annulus 96 has plural holes 100 extending therethrough.
One advantage of the invention is that plasma ions are excluded from the pumping annulus 44. This is advantageous because the pumping annulus interior surfaces can be formed of any convenient material without regard to its susceptibility to attack by plasma ions or compatibility of its sputter by-products with the plasma process carried out on the wafer. This also eliminates reduction in plasma density due to loss of plasma ions through the pumping annulus. Another advantage is that gas flow through the pedestal-to-side wall gap 46 is not obstructed even though plasma is confined to the interior chamber 10 over the wafer. Furthermore, by so confining the plasma to a smaller volume (i.e., in the portion of the chamber 10 directly overlying the wafer 52), the plasma density over the wafer 52 is enhanced. A further advantage is that stopping plasma ions from exiting through the slit valve opening 50 eliminates loss of plasma density over portions of the wafer 52 adjacent the slit valve opening 50.
In one example, each of the magnetic pole pair 60, 62 has a strength of 20 Gauss for a distance across the gap 46 of 5 cm, while each of the magnetic pole pair 70, 72 has a strength of 20 Gauss for a width of the slit valve opening 50 of 2 cm.
While the invention has been described with reference to preferred embodiments in which the plasma confining magnets are protected from attack from plasma ions and processing gases by being at least partially encapsulated in the chamber walls or within the wafer pedestal or within a protective layer, in some embodiments (as for example, the embodiment of FIG. 6) the magnets may be protected by being located entirely outside of the chamber walls. Alternatively, if the reactor designer is willing to permit some plasma interaction with the magnets, magnets may be located inside the chamber in direct contact with the plasma, although this would not be preferred.
While the invention has been described in detail by specific reference to preferred embodiments, it is understood that variations and modifications thereof may be made without departing from the true spirit and scope of the invention. | The invention confines the plasma within the chamber without relying entirely on the chamber walls by introducing a magnetic field across an area or plane through which plasma flow is to be stopped. For example, in order to prevent plasma from leaking or flowing through openings necessarily provided the chamber walls, a magnetic field is established at the entrance of the reactor chamber to such an opening, by placing a pair of opposing magnetic poles across the opening, for example. The magnetic field is sufficiently strong to prevent plasma leaking through the opening. | 7 |
[0001] This application is a continuation of U.S. application Ser. No. 12/267,068 filed Nov. 7, 2008, which claims the priority under 35 U.S.C. §119 of provisional application No. 60/996,262 filed Nov. 8, 2007, the disclosure of both of which are hereby incorporated herein by reference.
FIELD OF THE INVENTION
[0002] This invention relates in general to techniques for shopper checkout and, more particularly, to techniques that facilitate efficient checkout of a shopper. cl BACKGROUND
[0003] Shopper checkout is the process of identifying all of the products selected by a shopper, and then obtaining payment from the shopper for those products. Retail stores typically use two different techniques for shopper checkout. First, in the most common approach, a clerk employed by the store manually passes each product selected by the shopper past a universal product code (UPC) scanner, and the scanner reads the UPC code on each product. The UPC scanner is coupled to a computer, and the computer uses the scanned UPC code from each product to retrieve from a stored product list an identification of the product, and also the price of the product. The computer sums the individual prices of all products scanned in order to obtain a subtotal, and then adds any applicable taxes or other charges to the subtotal, thereby obtaining the total amount owed by the shopper. The clerk then obtains payment of that total amount from the shopper in order to complete the checkout process.
[0004] The other common approach is self-service checkout. During self-service checkout, it is the shopper rather than a store clerk who manually scans the UPC code on each product. A single clerk is typically present to monitor four or more self-service checkout stations, and to deal with any questions or problems encountered by shoppers operating the self-service checkout stations. The self-service approach is significantly less expensive for the store, because the store pays wages and benefits only for the single clerk who monitors several self-service checkout stations, instead of paying wages and benefits for several clerks who are each located at a respective different checkout station. On the other hand, the self-service approach has some drawbacks. For example, a shopper may inadvertently or intentionally fail to scan the UPC code on one or more products, such that the computer calculating the total amount due is not aware of those products and thus omits their prices from the total. As a result, the shopper ends up taking home one or more products that the shopper did not pay for.
[0005] While these traditional approaches have each been generally adequate for their intended purposes, they each have some drawbacks, and neither has been entirely satisfactory in all respects.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] A better understanding of the present invention will be realized from the detailed description that follows, taken in conjunction with the accompanying drawings, in which:
[0007] FIG. 1 is a diagrammatic fragmentary sectional top view of a portion of a retail store, and in particular shows a portion of the store where shoppers check out and pay for their purchases.
[0008] FIG. 2 is a diagrammatic fragmentary side view showing in an enlarged scale an interrogation zone present in the portion of the store depicted in FIG. 1 , and also showing a shopper and a shopping cart that are in the interrogation zone.
[0009] FIG. 3 is a block diagram of a control system that includes several electronic components shown in FIGS. 1 and 2 , as well as a central computer system that is operatively coupled to each of these electronic components.
[0010] FIG. 4 is a diagrammatic view of a master product list that is stored in a memory of the computer system of FIG. 3 .
[0011] FIGS. 5A and 5B are a flowchart showing a procedure that is part of the processing carried out by the computer system of FIG. 3 .
[0012] FIGS. 6 and 7 show respective tables of information that are each stored in the memory of the computer system of FIG. 3 , and that are used by the procedure of FIGS. 5A and 5B .
[0013] FIG. 8 is a flowchart showing a procedure that is an alternative embodiment of the procedure shown in FIGS. 5A and 5B .
[0014] FIGS. 9 and 10 show respective tables of information that can be substituted for the table of FIG. 6 , and used by the procedure of FIG. 8 .
DETAILED DESCRIPTION
[0015] FIG. 1 is a diagrammatic fragmentary sectional top view of a portion 10 of a retail store, and in particular shows the portion of the store where shopper checkout occurs. Shopper checkout is the process of identifying all of the products selected by a shopper, and then obtaining payment from the shopper for those products.
[0016] The portion 10 of the store includes a corridor or passage 12 that splits into two corridors or passages 13 and 14 , each of which leads to a respective one of two checkout areas 17 and 18 that are partially separated by a wall 21 . The corridors 13 and 14 each open into the associated checkout area 17 or 18 on one side thereof, and a single exit door 22 is provided on the opposite side thereof to permit shoppers to exit the store after completing the checkout process.
[0017] The checkout area 17 has three checkout stations 31 , 32 and 33 , and the checkout area 18 has three checkout stations 34 , 35 and 36 . Each of the checkout stations 31 - 36 includes a respective point-of-sale (POS) terminal 41 - 46 that is an electronic cash register of a known type. In FIG. 1 , the checkout stations 31 - 36 are each manned by a respective person 51 - 56 who is a store clerk. In an alternative configuration, the three POS terminals 41 - 43 in the checkout area 17 could be replaced with self-service POS terminals of a type well known in the art. In the case of self-service POS terminals, a single store clerk might be stationed nearby to monitor all three checkout stations 41 - 43 , or the store might elect to provide no store clerk in the checkout area 17 .
[0018] Shoppers who are waiting to check out proceed in single file down the corridor 12 . For example, FIG. 1 shows three shoppers 61 - 63 in the corridor 12 , each with a respective shopping cart 64 , 65 or 66 . An interrogation zone 68 is provided at the end of corridor 12 nearest the corridors 13 and 14 . The interrogation zone is discussed in more detail later. In FIG. 1 the shopper 63 with the cart 66 is currently located in the interrogation zone 68 .
[0019] In FIG. 1 , an electronic display 69 is provided at the intersection of the corridors 13 and 14 . Depending on what happens in the interrogation zone 68 , the display 69 will illuminate either an arrow pointing to the left or an arrow pointing to the right, in order to indicate to the shopper in the interrogation zone that he or she should proceed down either the corridor 13 or the corridor 14 . FIG. 1 shows two shoppers 71 and 72 with respective carts 73 and 74 who were directed to proceed down the corridor 13 to the checkout area 17 , and who are currently in the process of checking out. FIG. 1 also shows a shopper 77 with a cart 78 who was directed to proceed down the corridor 14 to the checkout area 18 , and who is currently in the process of checking out.
[0020] FIG. 2 is a diagrammatic fragmentary side view showing in an enlarged scale the interrogation zone 68 of FIG. 1 , and also showing the shopper 63 and shopping cart 66 in the interrogation zone. The shopping cart 66 contains several products 101 - 104 that the shopper 63 selected and intends to purchase. Although FIG. 2 shows four products 101 - 104 , the cart 66 could alternatively include a larger or smaller number of products. Each of the products 101 - 104 has a respective radio frequency identification (RFID) tag 106 - 109 mounted thereon. The tags 106 - 109 are each a type of device well known in the art, and are therefore not illustrated and described here in detail. A child 113 is sitting in the shopping cart. The shopper 63 may also have one or more personal effects in the cart, such as a purse.
[0021] In FIG. 2 , the shopping cart 66 is resting on a scale 116 of a known type, which weighs the cart 66 and everything in the cart, and then outputs an electrical signal representing the total measured weight. A digital camera 118 of a known type is stationarily supported above the scale 116 . Although FIG. 2 shows only one camera 118 , it would alternatively be possible to have two or more cameras that view the cart and its contents from different angles. The camera 118 records one or more images of the cart and its contents as the cart passes below the camera. The camera 118 then outputs these images in the form of electrical signals. The images from the camera 118 are then processed with image processing software in an effort to identify items present in the shopping cart 66 , including the number of products 101 - 104 , any child 113 , and any personal effects such as a purse. The camera 118 in FIG. 2 is responsive to visual light, and the recorded images are digital photographs. Alternatively, however, the camera 118 could be responsive to radiation in a waveband other than visible light, such as infrared radiation, or low-level x-ray radiation.
[0022] As the shopper 63 continues to push the cart 66 in a forward direction, the cart 66 will pass between two RFID readers 121 and 122 . The readers 121 and 122 are each a device of a well-known type, and are therefore not illustrated and described here in detail. The reader 121 is stationarily supported above the cart's path of travel, and the reader 122 is embedded in the floor below the cart's path of travel. Although FIG. 2 shows two readers 121 and 122 , it would alternatively be possible to have a larger or smaller number of readers. Also, FIG. 2 shows the readers 121 and 122 located respectively above and below the path of travel of the cart, but it would alternatively be possible to provide the readers 121 and 122 in other locations. For example, the readers 121 and 122 could be provided on opposite sides of the path of travel of the shopping cart 66 .
[0023] The readers 121 and 122 in FIG. 2 emit RFID signals of a known type. As the shopping cart 66 passes between the readers 121 and 122 , the signals emitted by the readers will reach most or all of the tags 106 - 109 . Each tag that receives a signal from either reader will produce in reply an RFID signal containing an identification code. The signal emitted by each tag will then be received by one or both of the readers 121 and 122 . The identification code in each received signal can be used to identify the tag that emitted the signal, and thus identify the particular product associated with that tag.
[0024] In theory, all of the tags will receive the interrogation signals from the readers, such that all of the tags will produce a signal in reply, and all of the signals from the tags will be received by the readers. But as a practical matter, some types of products make it more difficult to scan tags than other types of products. For example, if a product includes a significant amount of metal, the metal can provide a degree of electromagnetic shielding that interferes with attempts to communicate with the tag on that metal product, and/or with tags on other products located near the metal product. Similarly, if a product contains a significant amount of water, that may make it more difficult to communicate with the tag on that product, and/or with tags on other nearby products. As a result, the readers 121 and 122 may not always be able to accurately identify each and every product present in the shopping cart 66 . A further consideration is that the readers 121 and 122 cannot identify items in the shopping cart that do not have RFID tags, such as the child 113 , or personal effects of the shopper, such as a purse.
[0025] FIG. 3 is a block diagram of a control system 151 that includes several electronic components discussed above in association with FIGS. 1 and 2 , as well as a central computer system 152 that is operatively coupled to each of these electronic components. More specifically, FIG. 3 shows the POS terminals 41 - 46 and the display 69 of FIG. 1 , each of which is electrically coupled to the central computer system 152 . In addition, FIG. 3 shows the scale 116 , camera 118 and readers 121 - 122 of FIG. 2 , each of which is electrically coupled to the central computer system 152 . FIG. 3 does not show everything in the control system 151 or in the computer system 152 , but instead only shows selected portions thereof that facilitate an understanding of the present invention.
[0026] FIG. 3 shows a master terminal 156 that is electrically coupled to the central computer system 152 . The master terminal 156 and the central computer system 152 are not visible in FIGS. 1 and 2 , because they are located in the business office of the illustrated store, where they can be accessed by store management but not shoppers. Store management can provide the master terminal 156 with a password, and then use the master terminal to adjust data within the central computer system 152 . In the disclosed embodiment, the central computer system 152 includes computer hardware in the form of a conventional, commercially-available computer of the type commonly known as a personal computer. For example, the hardware of the computer system 152 could be a standard personal computer obtained commercially from Dell, Inc. of Round Rock, Tex. Alternatively, however, the hardware of the computer system 152 could be any other suitable computer hardware.
[0027] The computer system 152 includes a processor 161 and a memory 162 . The processor 161 is a microprocessor of a known type, and is therefore not described here in detail. The memory 162 is a diagrammatic representation of the storage available within the central computer system 152 , and may include more one than one type of memory. For example, the memory 162 may include one or more of a read only memory (ROM), a random access memory (RAM), a flash memory, a hard disc drive, or any other suitable type of memory.
[0028] FIG. 3 diagrammatically shows some of the information that is maintained within the memory 162 . More specifically, the memory 162 stores a software program 166 that is executed by the processor 161 . A portion of the program 166 is image processing software 167 . As mentioned earlier, the image processing software 167 accepts digital images produced by the camera 118 , and analyzes these images in an effort to identify the cart and items disposed in the cart, such as the products 101 - 104 ( FIG. 2 ), any child 113 , and/or any personal effects such as a purse.
[0029] The memory 162 also stores several segments of cart data, three of which are shown at 171 , 172 and 173 . Each segment of cart data 171 - 173 is created as a respective shopping cart passes through the interrogation zone 68 , contains information derived from that cart in the interrogation zone 68 , and is maintained in the memory 162 until checkout of that particular cart has been completed. The segments of cart data 171 , 172 and 173 are all similar, and therefore only the segment 171 is shown and described in detail.
[0030] More specifically, the segment of cart data 171 includes a measured cart weight 176 , which is the total weight of the particular cart and its contents, as measured by the scale 116 in the interrogation zone. The cart data segment 171 also includes an RFID tag count 177 , which is the number of RFID tags detected in that cart by the readers 121 and 122 . The cart data 171 further includes an RFID product list 178 . As discussed above, the RFID tag on each product produces a wireless signal containing a code that is used to identify the particular product on which that tag is mounted. The RFID product list 178 is a list of all products identified in the cart through communication with RFID tags on the products. The cart data segment 171 also includes an actual product count 179 , which is the number of separate products detected by the image processing software 167 , based on the images produced by the camera 118 .
[0031] The memory 162 stores a cart tare weight value 182 , which is the predetermined weight of the shopping cart 66 when it is empty.
[0032] As discussed above, some products make it more difficult to read RFID tags than other products. Consequently, it is possible for the RFID readers 121 and 122 to miss one or more products in a cart. Similarly, the camera 118 produces images that are analyzed in an effort to identify each of the products in the cart. However, the image processing software 167 may not be able to accurately identify each and every product in the cart. For example, a small product may be located beneath some larger products in the cart, and thus may not be visible in any of the images from the camera 118 . Consequently, for any given shopping cart, product lists generated from information obtained in the interrogation zone 68 using RFID technology or imaging technology may or may not include all of the products actually present in the cart.
[0033] The store may elect to permit a shopper to check out based solely on a product list generated from information obtained in the interrogation zone 68 . However, if that list is incomplete, the shopper would take home one or more products that the shopper did not pay for. This is commonly referred to as shrinkage of the store's inventory.
[0034] On any given day (or during certain periods of the day), a store may not be very busy, and this or other circumstances may make the store unwilling to accept much shrinkage. Accordingly, instead of checking out all carts based on product list(s) generated from information obtained in the interrogation zone 68 , the store may prefer to select a subset of the carts that are checking out, and perform a double-check or audit of the products actually present in each of those carts, in order to generate a very accurate product list for each such cart that is then used for checkout. On the other hand, on any given day (or during certain periods of the day), the store may be very busy and may have a long line of shoppers waiting to check out, and this or other circumstances may make the store more willing to accept a higher risk of shrinkage, in order to keep shoppers happy by checking them out more rapidly. Accordingly, the store may subject fewer carts (or no carts) to a double-check or audit.
[0035] In FIG. 3 , the memory 162 of the computer system 152 stores a business value 183 . The business value 183 can be set by store management using the master terminal 156 , and specifies the store's current willingness to tolerate shrinkage. More specifically, the business value 183 is an integer number between 1 and 10, inclusive. The values of 1 to 10 represent a sliding scale of tolerance for shrinkage, where 1 represents the maximum tolerance for shrinkage with the smallest percentage of carts being double-checked or audited, and 10 represents the least tolerance for shrinkage with a substantially higher percentage of carts being double-checked or audited.
[0036] The business value 183 influences the determination of whether each shopper in the corridor 12 ( FIG. 1 ) will be directed to proceed down the corridor 13 or down the corridor 14 , in a manner discussed in more detail later. Carts that are directed down the corridor 13 end up in the checkout area 17 , where checkout is completed using the RFID product list 177 generated from information obtained using RFID technology in the interrogation zone 68 . In contrast, carts that are directed to proceed down the corridor 14 end up in the checkout area 18 , where a double-check or audit is carried out on each such cart, and then checkout is completed based on the results of the double-check or audit. For example, in the checkout area 18 , one of the clerks 54 - 56 may use a standard UPC scanner to manually scan the universal product code (UPC) on each product in a cart, in order to generate a highly accurate product list that is then used for checkout.
[0037] The memory 162 stores a set of weighting values 184 . In the disclosed embodiment, there are six weighting values W 1 , W 2 , W 3 , W 4 , W 5 and W 6 , each of which is an integer value between 1 and 5 inclusive, where 5 represents the greatest weight, and 1 represents the least weight. The weighting values 184 can each be adjusted by store management through the master terminal 156 . The memory 162 also stores a default threshold 186 . In the disclosed embodiment, the default threshold is a single integer between 0 and 100 inclusive, and represents a percentage, such as 65%. The default threshold 186 can be adjusted by store management through the master terminal 156 .
[0038] The memory 162 also stores a master product list 188 . FIG. 4 is a diagrammatic view of the master product list 188 . The master product list 188 is shown in FIG. 4 as a table, with a separate row for each type of product carried by the store. Each row has the same set of fields, and some of these fields are depicted in the first row in FIG. 4 . In particular, for each product or row, there is a field 191 setting forth the name of the product, a field 192 setting forth the industry-standard UPC code for that product, a field 193 setting forth the price charged by the store for that product, a field 194 setting forth the weight of the product, and a field 195 setting forth a difficulty rating.
[0039] Each difficulty rating 195 is an integer number between 1 and 10, inclusive. As discussed above, some types of products (such as those that contain metal or water) are more likely to interfere with the scanning of RFID tags than other types of products. The numerical difficulty rating in the field 195 is an indication of the extent to which the associated product is likely to interfere with scanning of the RFID tag mounted on that product, or RFID tags on other nearby products. A value of 1 represents the least degree of interference or difficulty, and a value of 10 represents the greatest degree of interference or difficulty. Store management can use the master terminal 156 to change the information in the master product list 188 , including the difficulty ratings 195 . For simplicity, FIG. 4 shows the difficulty ratings 195 as an integral portion of the master product list 188 . However, the difficulty ratings 195 could alternatively be maintained in a separate list.
[0040] Referring again to FIG. 3 , the memory 162 in the central computer system 152 also stores several tables 197 , each of which is discussed in more detail later.
[0041] FIGS. 5A and 5B are a flowchart showing a procedure that is a portion of the processing carried out by the processor 161 under control of the program 166 . The flowchart of FIGS. 5A and 5B shows how the processor 161 decides whether to direct a shopper along either the corridor 13 or the corridor 14 . More specifically, as soon as a given shopping cart has been interrogated in the interrogation zone 68 ( FIGS. 1 and 2 ), the processor 161 carries out an evaluation that is based primarily on data collected during the interrogation. Then, the processor makes a decision about whether to direct the cart along the corridor 13 to the checkout area 17 , or along the corridor 14 to the checkout area 18 . As discussed above, in the checkout area 17 shoppers check out and pay based on the product list compiled using RFID technology. In contrast, in the checkout area 18 , the products in each cart are audited (for example by scanning UPC codes), in order to generate a new and accurate product list that is then used for checkout.
[0042] As discussed in more detail below, the procedure of FIGS. 5A and 5B involves successive evaluation of six different criteria. Each criteria looks for a respective different condition that suggests a likelihood the RFID product list 178 might not be fully accurate. If the cart fails to meet any one of these six criteria, then the contents of the cart are audited in the checkout area 18 . On the other hand, if the cart meets all six criteria, then the cart is sent to checkout area 17 , and is not audited.
[0043] In more detail, the routine of FIGS. 5A and 5B is entered at block 211 , and then control proceeds to block 212 . In block 212 , the processor 161 prepares a filtered product list. In this regard, FIG. 6 shows a table that is one of the tables stored at 197 ( FIG. 3 ) in the memory 162 , and that has six columns 216 - 221 . The left column 216 sets forth each possible value of the business value stored at 183 in the memory 162 ( FIG. 3 ), and the adjacent column 217 shows a corresponding difficulty threshold. In the disclosed embodiment, the difficulty threshold happens to be the same as the business value. For example, if the business value is currently 1 then the difficulty threshold is 1, and if the business value is 5 then the difficulty threshold is 5. The processor uses columns 216 and 217 to identify the difficulty threshold associated with the current value of the business value 183 .
[0044] The processor then identifies each product from the master product list 188 that currently has a difficulty rating ( 195 in FIG. 4 ) exceeding the current difficulty threshold obtained from column 217 . These products collectively constitute the filtered product list. The processor then compares this filtered product list to the RFID product list 178 ( FIG. 3 ) for the shopping cart that has just been interrogated. Basically, the processor is looking for products (if any) that are on both lists. Any product present on both lists will have a difficulty rating that suggests the product might have blocked access to one or more RFID tags, such that one or more products actually present within the cart may not appear on the RFID product list. In FIG. 5A , control proceeds to block 226 , where the processor checks to see whether the comparison yielded any matches, or in other words whether any product was on both lists. If any product is on both lists, then the RFID product list may not be accurate, and control proceeds to block 227 .
[0045] In block 227 , the processor causes the display 69 in FIG. 1 to illuminate an arrow pointing to the right, indicating to the shopper in the interrogation zone 68 that he or she should proceed down the corridor 14 to the checkout area 18 . In the checkout area 18 , the products in the cart will be carefully audited (for example by having a store clerk manually scan the UPC code on each product). Checkout will then be completed using the product list from the audit. From block 227 , the processor proceeds to block 228 , and exits the routine of FIG. 5B .
[0046] Referring back to block 226 , if it was determined that that there was no match, or in other words that no product on the RFID product list was also on the filtered product list, then control proceeds to block 231 . In block 231 , the processor 161 takes the RFID tag count 177 ( FIG. 3 ), and compares it to a tag count threshold. More specifically, with reference to FIG. 6 , the processor locates the current business value in column 216 , and then selects a corresponding tag count threshold from column 218 . In essence, as the number of products in the shopping cart increases (such that the number of RFID tags also increases), it becomes more difficult to accurately identify each and every tag with RFID technology. Stated differently, as the number of products and tags increases, there is a progressively increasing chance that the RFID identification process may have missed one or more of the products in a cart. In block 231 , the processor compares the RFID tag count 177 to the tag count threshold obtained from column 218 . If the tag count exceeds the threshold, then control proceeds to block 227 for an audit of the products in the cart. It will be noted from FIG. 6 , that, as the business value progressively increases, representing a progressively increasing preference for accuracy at checkout, the tag count threshold in column 218 progressively decreases, meaning that progressively smaller product counts will trigger an audit.
[0047] In block 231 , if the RFID tag count does not exceed the tag count threshold, then control proceeds to block 232 . In block 232 , the processor takes the measured cart weight 176 ( FIG. 3 ), and subtracts the cart tare weight 182 in order to determine the measured product weight, or in other words the total weight of all contents of the cart. Note that this measured product weight will include not only products in the cart, but also anything else in the cart, such as a child 113 ( FIG. 2 ) or personal effects such as a purse. However, to the extent that the image processing software 167 can identify a child and/or personal effects in the cart, it would optionally be possible to subtract a predetermined weight value from the measured product weight calculated in block 232 , in order to at least partially compensate for the child and/or the personal effect.
[0048] From block 232 , control proceeds to block 233 , where the measured product weight calculated in block 232 is compared to a weight threshold. With reference to FIG. 6 , the processor locates the current value of the business value in column 216 , and then selects a corresponding weight threshold from column 219 . If the measured product weight exceeds this weight threshold, then control proceeds from block 233 to block 227 for an audit of the contents of the cart. In essence, as the weight of products in the cart increases, either the total number of products is increasing, and/or the shopper is purchasing one or more heavier and potentially more valuable products, such as a television. It will be noted from FIG. 6 that, as the value of the business value in column 16 progressively increases, representing a progressively greater desire for an accurate product list at checkout, the weight threshold in column 219 progressively decreases, meaning that progressively fewer and/or lighter products will trigger an audit.
[0049] If it is determined in block 233 that the measured product weight does not exceed the weight threshold, then control proceeds from block 233 to block 236 . In block 236 , the processor takes the measured product weight determined in block 232 , and checks to see whether this measured product weight and the RFID tag count 177 both fall within a specified window width. In this regard, with reference to FIG. 6 , the processor locates the current value of the business value in column 216 , and then selects a corresponding window width from column 220 . FIG. 7 shows a table that is one of the tables stored at 197 ( FIG. 3 ) in the memory 162 , and that has 10 columns or “buckets” each relating a respective range of RFID tag counts to a respective weight range. The window width obtained from column 220 in FIG. 6 represents a number of adjacent columns in the table of FIG. 7 . For example, if the window width is 1, then that represents one column in the table of FIG. 7 , and the tag count and the measured weight should both be within the same column. Reference numeral 241 represents a window width of 1 column in FIG. 7 . If the RFID tag count is in the range of 21 to 25, then the measured product weight should be in the range of 81 to 100 pounds. The window 241 is a sliding window, and could be associated with any single column in the table of FIG. 7 , but the tag count and weight both need to be in that same column.
[0050] Alternatively, assume that the window width is 2 columns. Reference numerals 242 and 243 show two different possible positions of a sliding window having a width of two columns. Taking both of the window positions 242 and 243 into account, it will be noted that if the RFID tag count is in the range of 21 to 25, then the measured weight needs to be somewhere within the three columns spanned by the two window positions 242 and 243 , or in other words in the range of 61 to 120 pounds. As still another example, reference numerals 244 , 245 and 246 show three different positions of a sliding window having a width of 3 columns. Taking all three window positions 244 , 245 and 246 into account, it will be noted that if the RFID tag count is in the range of 21 to 25, then the measured weight would need to be in the range of 41 to 140 pounds.
[0051] These are examples of how the processor 161 determines in block 236 ( FIG. 5A ) whether the measured product weight and the RFID tag count are both within the current window width. If they are not both within the window width, then control proceeds to block 227 for an audit of the contents of the cart. In essence, most shopping carts will exhibit a relatively close correlation between the number of tags read and the measured weight of the products. But if there is a differential that exceeds a specified tolerance (the current window width), then it raises a question as to whether the RFID product was accurate, and thus an audit is appropriate.
[0052] If it is determined in block 236 that the measured product weight and the RFID tag count are both within the appropriate window width, then control proceeds to block 251 . In block 251 , the processor takes the RFID product list 178 , and looks up each listed product in the master product list 188 , in order to determine the actual weight 194 ( FIG. 4 ) of that particular product. The processor then adds up all of these weights in order to calculate the total weight of the products in the cart (as based on the information obtained using RFID technology). Then, the processor subtracts from the calculated product weight determined in block 251 the measured product weight determined in block 232 (which is based on the measurement made with scale 116 ). The processor takes the absolute value of the difference, in order to obtain a weight differential that is a positive number.
[0053] The measured product weight and the calculated product weight should usually be approximately the same. In other words, the calculated weight differential should usually be relatively small. The larger the weight differential, the greater the likelihood that the RFID product list may not include all of the products actually present in the cart, and thus the greater the justification for auditing the products in the cart. Accordingly, in block 252 , the weight differential calculated in block 251 is compared to a differential threshold. In this regard, with reference to FIG. 6 , the processor locates the current value of the business value 183 in column 216 , and then selects a corresponding differential threshold from column 221 . It will noted that, as the business value progressively increases, representing a progressively greater desire for accuracy in the product list used for checkout, the differential threshold in column 221 progressively decreases, such that progressively smaller weight differentials will trigger an audit of the contents of the cart. In block 252 , if the calculated weight differential exceeds the differential threshold obtained from column 221 , control proceeds to block 227 for an audit of the contents of the cart.
[0054] If it is determined in block 252 that the calculated weight differential does not exceed the specified differential threshold, then control proceeds to block 253 . In block 253 , the actual product count obtained by analyzing images from the cameral 118 is compared to the RFID product count obtained by interrogating RFID tags on products in the cart (or in other words the total number of products in the RFID product list 178 in FIG. 3 ). If these two product counts do not match exactly, then it suggests the RFID product list might not be entirely accurate, and so control proceeds to block 227 in order to carry out an audit of the contents of the cart. Otherwise, control proceeds from block 253 to block 254 .
[0055] In block 254 , the processor causes the display 69 in FIG. 1 to illuminate an arrow pointing to the left, indicating that the shopper in the interrogation zone 68 should proceed down the corridor 13 to the checkout area 17 , where checkout and payment will be carried out using the RFID product list 178 . Control then proceeds to block 228 , for an exit from the routine of FIG. 5B .
[0056] FIG. 8 is a flowchart showing a procedure that is an alternative embodiment of the procedure shown in FIGS. 5A and 5B . In FIGS. 5A and 5B , the procedure is influenced by the current state of the business value 183 ( FIG. 3 ), as explained in more detail above. In contrast, FIG. 8 takes a different approach that does not involve use of the business value 183 . In particular, as discussed in more detail below, the procedure of FIG. 8 successively evaluates six different criteria that are similar to the six criteria used in the procedure of FIGS. 5A and 5B . The check of each criteria results in the determination of a respective confidence level for that criteria, where the confidence level is expressed as a percentage. The six confidence levels are then weighted, and combined to arrive at an overall confidence level. If the overall confidence level is above a threshold, then the cart is directed to checkout area 17 , where checkout is carried out using the RFID product list 178 . On the other hand, if the overall confidence level is below the threshold, then the cart is directed to checkout area 18 , where an audit is performed, and checkout is carried out using the product list from the audit.
[0057] Turning now in more detail to FIG. 8 , processing begins at 301 , and proceeds to block 302 . In block 302 , the processor 161 takes the RFID product list 178 ( FIG. 3 ), and looks each listed product up in the master product list 188 ( FIGS. 3 and 4 ), in order to obtain the current difficulty rating 195 for that product. The processor then adds up all these difficulty ratings, and divides the sum by the number of products in the RFID product list, in order to obtain an average of the difficulty ratings for all products in the RFID product list 178 . The average will necessarily be a number between 1 and 10. The processor multiplies this average by 10, in order obtain a percentage, and then subtracts this percentage from 100% in order to obtain a first percentage “%1”.
[0058] Control then proceeds from block 302 to block 303 . In block 303 , the processor uses the RFID tag count 177 to determine a second percentage “%2”. More specifically, FIG. 9 is a table that is one of the tables stored at 197 ( FIG. 3 ) in the memory 162 , and that has four columns 306 , 307 , 308 and 309 . The left column 306 lists different possible values for the RFID tag count, and the right column 309 gives corresponding confidence levels, each expressed as a respective different percentage. The processor looks the RFID tag count 177 up in the left column 306 , and then selects the associated percentage from column 309 , for use as the second percentage “%2”.
[0059] The processor then proceeds from block 303 to block 311 . In block 311 , the processor calculates a measured product weight in the same manner already discussed above in association with block 232 in FIG. 5A . The processor looks this measured product weight up in column 307 of the table in FIG. 9 , and then selects the corresponding percentage from the right column 309 for use as a third percentage “%3”.
[0060] The processor then proceeds from block 311 to block 312 . In block 312 , the processor determines a forth percentage “%4” based on the RFID tag count 177 ( FIG. 3 ), and the measured product weight calculated in block 311 . More specifically, with reference to FIG. 7 , the processor identifies the column in FIG. 7 that corresponds to the RFID tag count 177 , and also identifies the column that contains the measured product weight. If they are both in the same column, then the number of columns spanned is 1. If they are not in the same column but are in adjacent columns, then the number of columns spanned is 2. Similarly, if they are in different columns that have a single further column between them, then the number of column spanned is three. In this manner, the processor thus determines the number of columns in FIG. 3 that are spanned by the RFID tag count and the measured product weight.
[0061] FIG. 10 is a table that is one of the tables stored at 197 ( FIG. 3 ) in the memory 162 . The left column 316 contains possible values for the number of columns spanned in FIG. 7 , and the right column 317 contains respective confidence levels, each expressed as a percentage. After determining the number of columns spanned in FIG. 7 , the processor looks this number up in the left column 316 of the table in FIG. 10 , and then selects the corresponding percentage from column 317 to serve as the fourth percentage “%4”.
[0062] The processor then proceeds from block 312 to block 321 . In block 321 , the processor uses the RFID product list 178 and the master product list 188 ( FIG. 3 ) to calculate a weight differential, in the same manner discussed above in association with block 251 of FIG. 5B . The processor looks this weight differential up in column 308 of the table in FIG. 9 , and then selects the corresponding percentage from column 309 for use as a fifth percentage “%5”.
[0063] The processor then proceeds to block 322 , where it compares the actual product count 179 ( FIG. 3 ) to the RFID product count, which is the number of products present in the RFID product list 178 . This is equivalent to the comparison that was already discussed above in association with block 253 of FIG. 5B . If the actual product count is exactly the same as the RFID product count, then the processor proceeds to block 323 , where it sets a sixth percentage “%6” to be 100%. Alternatively, if the actual product count and RFID product count are found to be different in block 322 , then the processor proceeds to block 324 , where it sets the sixth percentage “%6” to be 0%. From either of blocks 323 or 324 , the processor proceeds to block 326 .
[0064] As discussed above in association with FIG. 3 , the memory 162 contains weighting values 184 , and in particular six weighting values W 1 , W 2 , W 3 , W 4 , W 5 and W 6 that are each an integer between 1 and 5, inclusive. As shown in block 326 , the processor calculates for the cart of interest an overall confidence level “% C”, in particular by multiplying each of the percentages %1, %2, %3, %4, %5 and %6 by a respective weighting value W 1 , W 2 , W 3 , W 4 , W 5 or W 6 , by then summing the products of these multiplications, and by then dividing the sum of the products by the sum of the weighting values.
[0065] The processor then proceeds to block 327 , where it compares the calculated overall confidence level % C to the default threshold 186 ( FIG. 3 ). As discussed earlier, the default threshold 186 is a percentage specified by store management, such as 65%. If the calculated confidence level % C is greater than the default threshold, then the processor proceeds from block 327 to block 238 , where the cart of interest is sent for an audit, and then checkout is performed using the product list from the audit. In other words, in FIG. 1 , the display 69 is used to direct the shopper in the interrogation zone 68 to proceed down the corridor 14 to the checkout area 18 . In contrast, if it is determined in block 327 that the overall confidence level % C does not exceed the default threshold, then the processor proceeds from block 327 to block 239 , where the cart of interest is sent to have checkout completed using the RFID product list 178 ( FIG. 3 ). More specifically, with reference to FIG. 1 , the display 69 is used to direct the shopper in the interrogation zone 68 to proceed down the corridor 13 to the checkout area 17 . From either of blocks 328 and 329 , the processor proceeds to block 332 , for an exit from the routine of FIG. 8 .
[0066] The embodiment that is shown in the drawings and described above is configured with a single interrogation zone 68 , through which all shoppers must pass on their way to any of the checkout stations 31 - 36 . Further, the checkout stations are organized into two groups, where checkout stations 31 - 33 in checkout area 17 are used for RFID checkout, and checkout stations 34 - 36 in checkout area 18 are used to audit carts. Alternatively, however, the central interrogation zone 68 could be eliminated, and a single group of checkout stations could be provided, where the checkout stations are all identical. A shopper could freely go to any of the checkout stations. Each checkout station would have its own dedicated interrogation zone. Each checkout station would be capable of checking out a shopper based on either the RFID product list or a cart audit, depending on the result of the interrogation performed in that checkout station's dedicated interrogation zone.
[0067] The embodiment shown in the drawings is capable of accommodating the presence in a shopping cart 66 of a child 133 , or personal effects. Alternatively, however, in order to simplify the processing task carried out by the image processing software 167 , it would be possible to require each shopper to remove any child and/or personal effects from a shopping cart before the cart enters the interrogation zone 68 . Still another alternative would be to provide shopping carts that lack a child seat, in order to significantly reduce the likelihood that a child may be sitting in the cart when the cart reaches the interrogation zone.
[0068] For simplicity in disclosing the embodiment that is shown in the drawings, it has been assumed that all shopping carts in the store are identical, and thus have the same tare weight. However, some stores have two or more different types of shopping carts, such as traditional shopping carts and flatbed carts. Where there are two or more different types of carts, each type of cart will typically have a respective different tare weight. In that type of situation, each shopping cart would have an RFID tag mounted thereon. As a cart is passing through the interrogation zone 68 and the tags on products in the cart are being interrogated using RFID technology, the tag on that shopping cart would also be interrogated. Based on the information obtained from the cart's tag, the central computer system 152 would know the particular type of cart that is currently in the interrogation zone 68 , and thus the appropriate tare weight to use in carrying out calculations relating to the weight of that cart.
[0069] Although a selected embodiment has been illustrated and described in detail, it should be understood that a variety of substitutions and alterations are possible without departing from the spirit and scope of the present invention, as defined by the claims that follow. | A method and apparatus involve: providing a plurality of products that are each associated with a respective radio frequency identification tag; using radio frequency identification technology to automatically identify specific products in a group of products collected by a shopper; and evaluating whether or not to obtain payment from the shopper based on the radio frequency identification of products in the group. Based on the result of the evaluation, either payment is obtained from the shopper on the basis of the radio frequency identification of products in the group, or else the products in the group are audited, and then payment is obtained on the basis of the products identified by the audit. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates generally to an armored booth and more particularly to a protective enclosure that permits the occupants to approach armed individuals with reduced risk of harm to the occupants.
[0003] 2. Description of the Relevant Art
[0004] In recent years, there have been frequent situations in which a school, place of business, home or residence is occupied or taken over by an armed individual or individuals, such as, a deranged student, disgruntled employee or unhappy lover. In many cases there are hostages involved. The police authorities are faced with a difficult problem. In order to obtain access to the premises and arrest the perpetrators, they must risk personal injury or death. Frequently the result is a standoff with the hope that the perpetrators will come to their senses and surrender and that any hostages will not be injured or killed. The desired outcome does not always happen, however, and it is therefore desirable that improved means be provided for aiding the police authorities in overcoming such perpetrators and rescuing any hostages.
[0005] There are available in the prior art various devices which might be used in such situations. For example, the U.S. Pat. No. 4,781,101 to Zevuluni discloses a mobile maneuverable crowd control shield within which a policeman can be protected and can move from place to place. The U.S. Pat. No. 4,245,546 to Chaves discloses a bulletproof or armored shield that protects the occupant and allows the occupant to move from place to place. The U.S. Pat. No. 1,253,964 to Hack discloses a guardhouse that is movable from place to place by the person inside the guardhouse who is protected by the guardhouse. These devices, however, are not completely satisfactory, in that they do not, for example, deal with the problem of the policeman entering a building or with the perpetrator shooting at the feet of the policeman as the policeman moves toward the perpetrator.
SUMMARY OF THE INVENTION
[0006] One embodiment of the armored booth of the present invention might involve a housing formed of armored material. The housing has walls having gun ports therein adapted to permit gun shooting through the gun ports from the interior of the housing. There are also provided windows formed of transparent armored material mounted in the walls. Wheels are mounted on the housing and are adapted to support the housing above a ground or floor surface. A flange is mounted on the housing so as to extend inwardly above at least a portion of the wheels whereby a person inside of the housing can stand on the flange to prevent gun shots from harming the feet of the person.
[0007] Another embodiment of the armored booth of the invention includes a housing formed of armored material. Wheels are mounted on the housing and are adapted to support the housing in spaced relation above a ground or floor surface. The housing has a transverse dimension that is less than 36 inches. The housing and wheels have a vertical dimension which is less than 82 inches whereby the housing is capable of passing through a rectangular building door opening of a dimension 36×82 inches or greater. The housing has walls having windows formed of armored glass the walls having gun ports therein adapted to permit gun shooting through the gun ports from the interior of the housing.
[0008] Still another embodiment of the invention is an armored booth including a housing formed of armored material. The housing includes walls which have gun ports therein adapted to permit gun shooting through the gun ports from the interior of the housing. Windows formed of transparent armored material are mounted in the walls. The walls include a rectangular front wall, a rectangular rear wall and two rectangular side walls. Wheels are mounted on the housing and are adapted to support the housing in spaced relation above a ground or floor surface. The front wall and housing have a horizontal dimension that is less than 36 inches. The housing and wheels have a vertical dimension that is less than 82 inches whereby the housing is capable of passing through a rectangular building door opening of dimensions 36×82 inches or greater. The front wall has a pair of arm openings therein. There is also provided a pair of armored closure members each having an upper edge that is pivotally attached to the front wall above a respective opening of said pair of arm openings. Each of the closure members is hung over a respective one of the arm openings and closes the respective arm opening but is pivotal outwardly away from the front wall to permit a person inside of the housing reaching his arm through a respective arm opening to open a door handle of a door in a building door opening whereby the armored booth may be moved through the building door opening.
[0009] Still a further embodiment of the armored booth involves a housing formed of armored material. The housing includes walls having gun ports therein adapted to permit gun shooting through the gun ports from the interior of the housing. Windows formed of transparent armored material are mounted in the walls. The walls include a rectangular front wall, a rectangular rear wall and two rectangular side walls. A first pair of wheels is mounted on the front wall and a second pair of wheels is mounted on the rear wall. The wheels are adapted to support the housing in spaced relation above a ground or floor surface. The first set of wheels is swivel mounted whereby the wheels can turn in multiple directions. The second pair of wheels is swivel mounted whereby the wheels can turn in multiple directions but also are restrainable so that they can turn only in a plane extending front to rear of said housing. Bearings are mounted on the rear wall and are movable to restrain the second pair of wheels to turn in only a front to rear extending plane relative to said housing.
[0010] Still a further embodiment of the invention is an armored booth comprising a housing formed of armored material. The housing includes walls having gun ports therein adapted to permit gun shooting through the gun ports from the interior of the housing. Windows formed of transparent armored material are mounted in the walls and wheels are mounted on the housing and adapted to support the housing above a ground or floor surface. The walls include a rear wall that has a door opening in the rear wall. A door formed of armored material is hung on the rear wall and is pivotal in a horizontal direction between a first position closing the door opening and a second position opening the door opening. Posts are mounted on the rear wall. The door is hung on the posts and is liftable off of the posts to serve as an armored shield.
[0011] Another embodiment of the invention is an armored booth comprising a housing formed of armored material. The housing has a wall with a window formed of transparent armored material mounted in the wall. The wall has a pair of arm openings therein. There is provided a pair of armored closure members each having an upper edge pivotally attached to the wall above a respective one of the arm openings and closing the respective arm opening but pivotal outwardly away from the front wall to permit a person inside the housing reaching his arm through the respective arm opening to open a door handle or a door in a building door opening whereby the armored booth may be moved through the building door opening.
[0012] Still a further embodiment of the invention involves providing a leveraged lift for lifting an armored housing over obstacles when the housing wheels are impeded.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] [0013]FIG. 1 is a perspective view of the armored booth of the present invention showing in dotted lines the booth entering a door opening in a building.
[0014] [0014]FIG. 2 is a perspective view of the armored booth looking toward the rear of the booth.
[0015] [0015]FIG. 3 is a view similar to FIG. 2 showing the rear door of the armored booth removed.
[0016] [0016]FIG. 4 is a perspective view of the front of the armored booth of FIG. 1 showing one of the steps in opening the door of a building.
[0017] [0017]FIG. 5 is a fragmentary perspective view similar to FIG. 1 of an alternative embodiment of the armored booth of the present invention.
[0018] [0018]FIG. 6 is a fragmentary view of an alternative wheel arrangement of the present invention.
[0019] [0019]FIG. 7 is a fragmentary view of an alternative armored booth of the present invention.
[0020] [0020]FIG. 8 is a fragmentary view of an alternative wheel arrangement of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
[0022] Referring to FIG. 1, there is illustrated a preferred embodiment of an armored booth 20 which includes a housing 21 including a front wall 22 , rear wall 25 and side walls 26 . Each of the walls 22 , 25 and 26 has a window 27 that is located at the normal height of the eyes of a person so that the occupant of the booth can see to shoot a gun through the gun port 30 located in each of the front and side walls of the armored booth. In the case of the front wall 22 there is an additional window 31 provided which allows the occupant of the armored booth to see what sort of obstacles might be in front of the armored booth as it is moved along the ground or floor. The windows 27 and 31 are formed of armored transparent material such as armored glass or the like. Also the walls 22 , 25 and 26 are formed of armored material. One example of an appropriate material for the walls is ⅛” thick aluminum and Level 3 or 4 Kevlar fabricated by Supreme Corporation of Goshen, Ind. Level 3 or 4 refers to the commercial bullet resistant rating system known as ______ .
[0023] The Kevlar fabric armored material may also be obtained commercially under the trade name Yellow Jacket. The armored glass is also available commercially from Protective Armored Systems of 140 Crystal Street, Lenox Dale, Mass. 01242. The gun ports may be merely openings or may be commercially available gun ports available, for example, from Supreme Corporation of P.O. Box 483, Goshen, Ind. 46627. Such gun ports can be closed with an armored closure so as to obstruct a bullet from coming into the booth from outside of the booth.
[0024] The housing also includes an armored top 35 that is rectangular and has a rectangular ventilation opening 36 in the center of the top. Mounted directly above and completely covering the ventilation opening 36 is an armored member 37 secured to the top 35 by four spacers 40 located at the corners of the member 37 . The top 35 and member 37 are formed of the same armored material as the walls 22 , 25 and 26 .
[0025] The armored booth has a first pair of wheels 45 mounted on the front of the booth and a second pair of wheels 46 mounted on the rear of the booth. The wheels in a preferred embodiment of the invention have a diameter of eight inches which allows them to roll over bumps in the ground or floor surface. The wheels 45 and 46 are swivel mounted by mounting members 47 and 50 . The wheels 45 and 46 support the housing in spaced relation above the ground or floor surface. It is preferred that this spacing be approximately two inches although the booth is usable with spacings less than and greater than two inches. The housing 21 has a flange 50 mounted on the housing and specifically on the rear, front and side walls of the housing. The flange extends inwardly above the wheels and allows a person inside the housing to stand on the flange so as to prevent gun shots from harming the feet of the person.
[0026] [0026]FIG. 1 also shows in dotted lines the entryway or door opening 55 of a building. The armored booth of the present invention is intended to be able to go through a door opening of a building. Typical door openings have dimensions that are 36×82 inches. Therefore the vertical height of the housing 21 and the wheels which support the housing off the ground or floor surface should be less than 82 inches. Also the transverse dimension of the housing is less than 36 inches, which is the typical transverse dimension of a door opening in a building.
[0027] Referring to FIG. 2 the rear of the armored booth is illustrated in more detail and includes the rear wall 26 . The housing has a door opening 60 in the rear wall 26 . The door opening 60 is closed by the housing door 61 which is formed of armored material and is hung on the rear wall and is pivotal in a horizontal direction between a first position closing the housing door opening and a second position illustrated in FIG. 2 opening the housing door opening 60 . The door 61 has a latch 64 . FIG. 2 also shows handles 62 , 63 and 65 . The handles 62 and 63 are mounted on the housing door 61 and used to lift the door 61 off of the posts 66 shown in FIG. 3. The posts 66 are mounted on the rear wall 26 and project upwardly and are normally received within the sockets 70 mounted on the rear door 61 . When the rear door 61 is removed as in FIG. 3 it can be used as an armored shield. Also as illustrated the rear door 61 has an armored transparent window 27 and gun port 30 that is available to the user of the shield and door 61 . The door 61 may be formed of the same armored material used for the walls 22 , 25 and 26 .
[0028] As described above the rear wheels 46 are swivel mounted by mounting members 50 . The rear wheels 46 however may be restrained in a plane extending front to rear of the housing by means of bearings 71 which are mounted on shafts 72 . The shafts 72 are fixed in and project from a bar 75 . The bar may be latched in an upward position which causes the bearings to be moved away from the wheels 46 so that they are free to swivel. When the bar 75 is not latched in the upward position it may be moved down to the illustrated position of FIG. 2 whereby the wheels 46 are restrained by the bearings 71 so that they can only turn in a plane front to rear of the housing. It is normally easier to move the housing from place to place with the rear wheels 46 restrained in the front to rear plane and with the front wheels in a swiveling condition. However, if it is desired to rotate the armored booth in place it is preferred to allow the rear wheels to swivel.
[0029] Referring to FIG. 6 an alternative embodiment of the invention includes having a peripheral slot 80 surrounding each rear wheel 46 and the projection 72 ′ being only a single projection instead of a projection on either side of the wheel so that the projection 72 ′ has a bearing 71 ′ on its distal end. The arrangement illustrated in FIG. 6 operates in the same fashion as the embodiment illustrated in FIG. 2 to restrain the wheels 46 ′ in a plane extending front to rear of the housing. Still another alternative embodiment is shown in FIG. 8 wherein the wheel 46 ″ may be restrained in a plane extending front to rear of the housing by projecting flat members 72 ″ which are mounted on a plate 125 that is horizontally slidably mounted on the rear wall 26 ″ of an armored booth.
[0030] Referring to FIG. 5, there is shown an alternative embodiment wherein the front wheels 45 ′ are mounted on a plate 85 ′ pivotally mounted at the center 86 ′ of the plate to the front wall 22 ′. The wheel mounting members 90 ′ to which the wheels 45 ′ are swivel mounted by the swivel members 47 ′ are secured to the opposite ends 87 of the plate 85 ′. Thus if the housing encounters a bump that raises one of the wheels 45 ′ relative to the other wheel 45 ′, the plate 85 ′ pivots about the axis of mounting 86 ′ so that it is easier to move the housing from place to place.
[0031] Referring to FIGS. 1 and 4, the front wall 22 has a pair of arm openings 99 therein each of which is covered by a respective armored closure member 100 . Each of the closure members 100 has an upper edge which is pivotally attached to the front wall 22 above a respective one of the openings. Each of the closure members can be swung away from the front wall to permit a person inside the housing reaching his arm through a respective opening to open a door handle 101 of a door 102 in a building door opening such as the door opening 55 of FIG. 1. Two arm openings 99 are provided one on each side of the armored booth 20 so that a door handle on either side of the building door can be opened.
[0032] When in use the armored booth may be impeded by a large bump, step up or other variation from flat surface over which the armored booth is moved. A leveraged lift 110 is provided to clear such obstacles. The leveraged lift is pivotally mounted on the housing and the lever arms 111 and 112 are suitably proportioned to ease lifting the housing over the obstacle. This feature may or may not be provided in the embodiment of FIGS. 1 - 7 . Also this feature may be provided in wheeled armored booths having housing of other shapes and sizes than described in connection with FIGS. 1 - 6 . Alternatively two of the leveraged lifts 110 may be provided, one on each of the two sides of the housing. The two leveraged lifts may be used independently or both may be used at the same time to lift the front two wheels 45 over an obstacle blocking both wheels.
[0033] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only some of the preferred embodiments have been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.
[0034] As examples of some of the other embodiments of the invention that are desired to be protected, the armored booth might have an outside housing configuration other than the rectangular configuration of FIGS. 1 - 3 and might have the configuration for example as shown in the Zevaluni U.S. Pat. No. 4,781,101. Alternatively, the outside housing configuration might be as shown in the Chaves U.S. Pat. No. 4,245,546 but with the modification that wheels such as 45 or 45 ′ and 46 would be provided and mounted on the housing or shield of the Chaves patent to support the housing in spaced relation to the ground or floor as described and shown above in connection with the preferred embodiment of FIGS. 1 - 3 . Each of these other embodiments of this paragraph would be provided with the flange 50 mounted on the housing at the lower edge thereof so as to allow the person inside the housing to stand on the flange so as to prevent gun shots from harming the feet of the person.
[0035] Still other embodiments of the invention desired to be protected involve use of an outside housing configuration other than the rectangular configuration of FIGS. 1 - 3 and also eliminating the wheels 45 and 46 . Such an alternative embodiment is shown fragmentarily in FIG. 7 as having the doors 100 ′, arm openings 99 ′ and armored windows 27 ′ and 31 ′ in the wall 22 ′.
[0036] Still further embodiments of the invention include providing an armored housing of any configuration and dimensions for the housing but having the above-described wheel system. Specifically the housing is provided with front wheels 45 which are swivel mounted. The housing also has rear wheels 46 which are also swivel mounted but are also restrainable so that they turn only in a plane extending front to rear of the housing. These embodiments are also provided with bearings mounted on the housing and movable to restrain the rear wheels to turn only in a front to rear extending plane relative to said housing. | An armored booth that functions as a protective enclosure permitting the occupants to approach armed individuals with reduced risk of harm to the occupants. The booth includes a housing formed of armored material and proportioned to be able to enter the doorway of a building. The housing has armored windows and gun ports. The housing has wheels and may be moved from place to place by the occupant walking inside of the housing. | 5 |
BACKGROUND Or THE INVENTION
[0001] A. Field of the Invention
[0002] The present invention relates to bases or supports for vertically extending or elevating structures, and, in particular, to portable or temporary footings or bases for the same.
[0003] B. Problems in the Art
[0004] A wide variety of ways to support vertically extending structures have been developed over time. Special considerations come into play for structures that extend substantial distances vertically, and further, when the structures may experience forces that tend to tip the structures, such as wind.
[0005] Structure and stability issues become even more acute in situations where support for the vertical structure is desired to be portable or temporary. If the foundation or base cannot utilize any permanent footings in the ground, a primary source for providing stability to a vertical structure does not exist.
[0006] A few specific examples will illustrate this point. Situations exist where it would be desirous to have high-powered, wide area lighting, but on a temporary basis. The practical problems are, first, how does one transport such a system, especially when it is desirable to have the lights elevated to substantial distances vertically in the air; and second, how does one support and keep stable such elevated lighting fixtures through a variety of environmental conditions such as winds?
[0007] One situation where wide-area portable lighting is desired is with regard to construction sites. There are existing systems for temporary construction site lighting which tend to be on portable trailers or trucks. Lighting fixtures can be installed on foldable or extendible booms or frames. These types of conventional portable lighting units generally each require a separate vehicle to transport them from location to location. Also, they tend to be able to elevate the lights no more than perhaps 15′ to 35′. This does not allow for large area lighting. Additionally, because the lights are relatively close to the ground, glare problems can exist for workers and for traffic. Still further, many of these lighting systems are limited in height and number of lights, because of limitations of the base. Basically, existing systems tend to be no more than just a few light fixtures on a scaffold or foldable tower that does not extend very far into the air.
[0008] Some truck-based systems with larger, extendible booms exist. For example, U.S. Pat. Nos. 4,423,471, 4,712,167, 5,207,747, and 5,313,378 disclose high-powered lighting fixtures which can be extended much higher in the air (much over 30′) and are portable because they are mounted to trucks. However, such systems are expensive, both in original cost and operation, especially for areas such as constructions sites. Also, the trucks on which the fixtures are mounted would be out of use during the time the portable lighting was in use.
[0009] Therefore, a system has been developed which essentially consists of a transportable base that can be transported on conventional over-the-road trucks such as semi-trailers, can be manipulated by forklifts, and which can support a substantial sized light pole and array of light fixtures. Such a system is disclosed in commonly owned and co-pending U.S. Ser. No. 08/853,173. This system is relatively low-cost, can support a very tall vertical structure, and is portable. However, it is not adjustable in a variety of situations.
[0010] For example, such a base is pre-manufactured and fixed in perimeter size and in weight. It is also fixed in all dimensions and characteristics. If selected for a certain use, it may not be functional for another use. It may support a 50′ pole with five (5) 30″ diameter light fixtures in low-wind or no-wind conditions, but not be able to support the same in substantial winds.
[0011] Therefore, with regard to temporary lighting, there is a real need in the art for an improved system which provides more flexibility and adjustability over a wide variety of situations.
[0012] Similar problems exist with regard to supporting or elevating other types of structures. For example, there is a need for a more versatile and flexible footing or base-support for vertical towers, scaffolds, and trusses that are not needed on a permanent basis.
[0013] It is therefore a principal objective of the present invention to provide an apparatus and method for a temporary spread footing that solves or overcomes the problems or deficiencies in the art. Other objects, features, and advantaged of the present invention include an apparatus and method for temporary spread footing that:
[0014] 1. Have a known resistance to overturning moment, but which are adjustable for variable attachments and conditions.
[0015] 2. Have expandable dimensions and weight as compared to when configured for transport.
[0016] 3. Allow interchangeable devices and add-on devices to be utilized.
[0017] 4. Provide for a more efficient use of space and strength for a supporting base or footing.
[0018] 5. Are adaptable and flexible for many situations and for moving, both at a location or site and to a different location or site.
[0019] 6. Can be utilized with a variety of different vertical or elevated structures.
[0020] 7. Are economical, efficient, and durable.
[0021] These and other objects, features, and advantages of the present invention will become more apparent with reference to the accompanying specification and claims.
SUMMARY OF THE INVENTION
[0022] The present invention includes an apparatus and method for a portable base or spread footing. The apparatus includes a frame-work that further includes a mount for a weight. The top of the frame-work includes a connection to which a structure can be removably attached. The top and bottom of the frame-work are spaced apart. A space or open area can be intentionally defined by the frame-work between the top and bottom into which can be placed one or more removable devices. The frame-work can also support a plurality of outriggers extendible from the base.
[0023] The method of the invention includes constructing a base frame with a substantial opening between top and bottom. The size of the base-frame is such that it can be transported in conventional, over-the-road vehicles. The structure to be elevated and supported is pre-evaluated. From the pre-evaluation, an appropriate amount of weight is added to the base frame-work and outriggers can be utilized to provide needed stability and resistance to overturning moment for the particular structure.
[0024] A variety of configurations can be created with the frame-work by interchangeable devices such as weights, on-board power generators, and other equipment. A variety of different structures can be supported and elevated to withstand various environmental factors such as wind.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] [0025]FIG. 1 is a perspective view of a preferred embodiment of the invention supporting a vertical pole (partially shown).
[0026] [0026]FIG. 2 is similar to FIG. 1, but shows in an exploded view weights that can be removably attached to the base frame-work and, with broken lines, shows the maneuverability and adjustability of the outriggers.
[0027] [0027]FIG. 3 is a top plan view of FIG. 1.
[0028] [0028]FIG. 4 is a side, elevational view of the base of FIG. 1 positioned on a generally flat ground area.
[0029] [0029]FIG. 5 is similar to FIG. 4, but shows the base located on uneven ground.
[0030] [0030]FIG. 6 is a reduced perspective view of the embodiment of FIG. 1 used in conjunction with a light pole and an array of light fixtures.
[0031] [0031]FIGS. 7 and 8 are similar to FIG. 6, but show in more detail a hollow pole positioned over an upward extending stub (FIG. 7) and the slip-fit of the hollow pole over the stub (FIG. 8) as a means of attaching a pole to the base.
[0032] [0032]FIGS. 9 and 10 are similar to FIG. 6, but show a pole hingeable along its length which can be pivoted down for access to the top of the pole.
[0033] [0033]FIG. 11 is a reduced perspective view of a plurality of bases similar to FIG. 1 used to support the four lower ends of a vertical tower.
[0034] [0034]FIG. 12 is a perspective view of the use of a plurality of the portable bases of FIG. 1 to support a plurality of legs of a scaffold and truss arrangement.
[0035] [0035]FIG. 13 is an enlarged perspective view of an outrigger of FIG. 1.
[0036] [0036]FIG. 14 is a still further enlarged partial top plan view of FIG. 13.
[0037] [0037]FIG. 15 is an elevational sectional view taken along line 15 - 15 of FIG. 14 showing the outrigger extended. FIG. 15A is identical, but showing the outrigger retracted.
[0038] [0038]FIG. 16 is a depiction of a placard or chart useable by an operator of the invention to determine outrigger length and total weight of the system for varying wind speeds to resist overturning.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0039] A. Overview
[0040] For a better understanding of the invention, a preferred embodiment will now be described in detail. Frequent reference will be taken to the drawings. References numerals or letters will be used to indicate certain parts or locations in the drawings. The same reference numerals or letters will be used to indicate the same parts and locations throughout the drawings unless otherwise indicated.
[0041] B. Environment of the Preferred Embodiment
[0042] The preferred embodiment will be discussed in the context of a portable, temporary base or spread footing to support a substantial length, vertically positioned pole, that supports a plurality of high-intensity, wide-area lighting fixtures. By substantial, it is meant that the poles are much longer than 20′ to 30′. The light fixtures are high-intensity arc lamps placed in bowl-shaped reflectors of approximately 2′ to 3′ in diameter. These types of fixtures are the same or similar to those that are conventionally used for outdoor sports lighting. An example of these lights are Musco Sports Lighting Model Sports Cluster II, Level VIII, or TLC available from Musco Sports Lighting, Inc., Oskaloosa, Iowa.
[0043] The environment and context of the preferred embodiment will also be with respect to the use of such lights for a construction site or similar lighting. The lights will therefore be outdoors and subject to the range of environmental conditions that may exist at any location, including winds of substantial velocity and varying ground and terrain topography and make-up.
[0044] It is to be understood that other analogous uses of lights of this nature are possible. It is also to be understood that other uses for supporting structures are possible with the base.
[0045] C. Apparatus Of The Preferred Embodiment
[0046] [0046]FIG. 1 illustrates a base 10 according to the present invention. Base 10 includes a bottom (indicated generally at 12 ), a top (indicated generally at 14 ), outriggers 16 and a connection member (indicated generally at 18 ), on top 14 for connection to a vertical pole 20 . As can be seen by FIG. 1, bottom 12 consists of parallel tubes 26 and 28 . Top 14 comprises parallel tubes 30 and 32 (turned 90° from tubes 26 and 28 ) with cross-members 34 and 36 . Corner tubes 40 , 42 (see FIG. 3), 44 , and 46 extend between top 14 and bottom 12 . Cumulatively, corner tubes 40 , 42 , 44 , 46 , top 14 and bottom 12 define a box-type frame-work.
[0047] Completing base 10 are two tubes 48 and two tubes 50 (in a cross shape) and side tubes 52 and 54 . Each of the foregoing components of frame or base 10 can be welded or otherwise rigidly connected. Pieces 34 and 36 may or may not be tubular and are welded or otherwise attached into cut-out recesses in the tops of tubes 30 and 32 . Similarly, cross-shaped tubes 48 and 50 can be welded into position in cut-outs in corner tubes 40 , 42 , 44 , and 46 , and converge to a central area at their opposite ends.
[0048] Vertical tubes 40 , 42 , 44 , and 46 could be 6″ by 6″ steel tubing or 5″ by 5″. FIG. 1 illustrates the four outriggers 16 . Each outrigger 16 comprises a telescoping arm (here made up of first telescoping section 56 and a second telescoping section 58 ) each of which telescopes out of an open end (at each corner tube 40 , 42 , 44 , and 46 ) of one of tubes 48 or 50 . A jack 60 at or near the distal end of section 58 of outriggers 16 includes a ground contacting foot 64 at the end of an extendible leg 62 . Foot 64 can be adjusted along the axis of leg 62 by a manually operated handle 66 .
[0049] The frame 10 therefore has outer dimensions that basically define a box. It is primarily made of tubing and has substantial open space between top 14 and bottom 12 . Frame 10 is therefore strong but comparatively light. It cam be moved and transported relatively easily. The feet 64 at the ends of outriggers 16 can be positioned substantially away from the frame to greatly increase the overall “foot print” or lateral spread of base 10 on the ground and thus the resistance to overturning moment.
[0050] As illustrated in FIG. 1, a weight 22 (for example, concrete) is mountable to bottom 12 of base 10 by mounts 24 (only two shown). Weight 22 could include slots or openings 25 configured to receive the forks of a forklift that could grab weight 22 and maneuver it into position relative to frame or base 10 to then allow attachment of mounts 24 to frame or base 10 . It would also allow the forklift to grab the combined weight 22 and base 10 (and/or pole 20 and anything suspended by pole 20 ) to move the combination.
[0051] [0051]FIG. 1 further illustrates that pole 20 could be attached at its lower end to a plate 68 . Plate 68 in turn could be positioned between tubes 34 and 36 and include some type of releasable locking mechanism (not shown) to hold plate 68 in place and yet allow releasable attachment and detachment from base 10 .
[0052] Pole 20 could have a lower flange 82 which could be bolted to plate 18 by bolts 150 to form a 16″ bolt circle with 8 ¾″ bolts (See FIG. 1).
[0053] In the preferred embodiment the following is a table of cross-sectional dimensions and thickness of certain of the parts:
REF. # HEIGHT WIDTH THICKNESS 22 48″ 48″ 10″ (approx. 3,000 lbs.) 26/28 6″ 12″ ¼″ w 30/32 6″ 12″ ¼″ w 34/36 3″ 8″ ⅜″ w 40/42/ 6″ 6″ ⅜″ w 44/46 48 5″ 9″ {fraction (5/16)}″ w (36-7/8″ long) 50 6″ 10″ ¼″ w (× 33-15/16″ long) 52/54 6″ 9″ ¼″ w 56 5″ 9″ ¼″ w (× 33-15/16″ long) 58 4″ 8″ ¼″ w (× 33-15/16″ long) 68 24″ 36″ 1″
[0054] Each of the tubing members of base 10 can be ASTM A500 Grade B steel structural tubing.
[0055] following is a table of some other dimensions as indicated by the corresponding reference letters in the drawings (see particularly FIGS. 2, 3, and 4 ):
REF. LETTER INCHES A 10″ B 10″ C 24″ D 10″ E 48″ F 48″ G 60″ H 48″ I 10″ J 60″ K 24″ L 108″ M 54″ radius N 54″ O 36″ (min) P 12″ Q 108″ square
[0056] Therefore FIGS. 1 and 2 illustrate the basic structure of the apparatus according to the preferred embodiment of the invention. Base 10 comprises a box-like tubular frame having a substantially open space between the top 14 and bottom 12 . An open space between tubes 26 and 28 of bottom 12 allow a heavy (in the preferred embodiment around 2,000 lbs.) concrete block to be moved therebetween and removably mounted. This weight, therefore, would exist at the lower-most or in or near the bottom-most plane of base 10 .
[0057] The space in base 10 could be used for storage. Examples are tool box(es), job box(es), parts, tools, generators, electrical components, or other components associated with what might be elevated on the pole.
[0058] On the other hand, top 14 of base 10 extends a substantial distance above the bottom of base 10 and provides, in perimeter dimensions, a fairly large platform area upon which a structure can be mounted.
[0059] Outriggers 16 allow the diameter of base 10 to be almost doubled in size with a corresponding substantial increase in the resistance to overturning moment, as opposed to just base 10 itself. Jacks 60 can be any of a wide variety of devices, but in the preferred embodiment can be trailer jacks manually operated. An example of jack 60 is Bulldog 10,000-lb capacity Top Wind Heavy Duty Trailer Jack. Other types are possible.
[0060] [0060]FIG. 2 is similar to FIG. 1, but shows in exploded form the detachment of a concrete weight 22 (by disconnecting brackets 24 from frame 10 held in place by bolts). Additionally, FIG. 2 illustrates that one or more further weights, such as indicated at 70 , could be placed into base 10 , if desired. Weight 70 has a triangular end which would mate in between crossed-tubes 48 and 50 above the location of weight 22 when mounted to base 10 . Therefore, several additional weights 70 , configured to mate into or attach to base 10 could be also be utilized to add additional weight to base 10 .
[0061] [0061]FIG. 2 also shows mounting straps 72 and 74 which extend between pieces 34 and 36 of base 10 and can lock down plate 68 to base 10 . Removable straps 72 and 74 allow plate 68 and pole 20 (attached to plate 68 by bolting of pole flange 82 to plate 68 or otherwise) to be removed from base 10 .
[0062] [0062]FIG. 2 also shows in ghost lines the extendibility and retractability of outriggers 16 , as well as the adjustability of foot 64 transversely to the longitudinal axis of the outriggers 16 .
[0063] [0063]FIG. 3 illustrates the substantial increase in resistance to overturning moment made possible by outriggers 16 versus just the outer dimensions of base 10 . Circle M (54″ radius) indicates the basic resistance to overturning moment presented by the outriggers 16 . Circle M is inscribed within a box Q which is 108″ square and is defined by the outer ends of outriggers 16 . The “foot print”, so to speak, of base 10 (108″×108″) and the 54″ moment arm, along with the substantial weight that can be added to base 10 , provides a substantial footing that resists overturning moment for a substantial load and any expected forces against that load. The tubular members and other structural members of base 10 are selected to be of enough strength to support any weight added thereto, as well as any stresses caused by the load and forces against, on or against it. On the other hand, FIGS. 2 and 3 illustrate that when outriggers 16 are retracted back into base 10 and weights 22 and 70 are removed, the perimeter dimensions are approximately 5′ by 5′. FIG. 2 shows that the height of base 10 , with pole 20 removed, is around 5′ tall. This structure would therefore easily fit within conventional over-the-road transportation such as semi-trailer trucks. Removability of weights 22 and 70 and the size of base 10 would allow even several of bases 10 to be transported in conventional semi-trailer trucks.
[0064] [0064]FIG. 4 also illustrates the height of base 10 . Reference letter N indicates the height between the bottom plane of bottom 12 and the top plane of top 14 to be 60″. Reference letter O indicates the distance between the top of outrigger 16 and just below the top plane of top 14 to be 36″ minimum. This could be extended upwardly if desired.
[0065] [0065]FIG. 4 also shows that outrigger jacks 60 extend so that feet 64 extend below the plane defining the bottom of bottom 12 of base 10 . It is preferable that when installed, no part of base 10 contact the ground and that it be entirely supported by feet 60 of outrigger 16 to get maximum stability and resistance to overturning moment.
[0066] [0066]FIG. 4 shows base 10 on a generally flat surface 76 , such as the ground. In comparison FIG. 5 illustrates uneven ground 78 . Jacks 60 can be operated to keep base 10 level even if ground 78 is not.
[0067] [0067]FIG. 6 illustrates base 10 of FIGS. 1 - 5 in combination with a pole 20 which suspends an array 80 of light fixtures. Array 80 comprises a set of cross-arms which are attached to the upper end of pole 20 by a means known within the art. In this embodiment pole 20 is hollow and made of tubular steel. It is attached to flange 82 at its bottom which is in turn fixed to plate 68 which is removably attachable to base 10 .
[0068] Pole 20 can be of various lengths. One possible range of lengths would be 40′ to 80′. The number of fixtures of the array 80 can vary, but usually would be anywhere from one (1) to twelve (12) fixtures. The object depicted in ghost lines by reference numeral 84 , is intended to represent a device that can be placed into the space between top 14 and bottom 12 of base 10 . In this example, device 84 could be an electrical power generator (self-contained, diesel powered) that could be removably positioned into base 10 and serve to operate lighting fixture array 80 . Ghost lines 86 are intended to represent another device that could be placed into base 10 such as ballasts for the light fixtures or other electronic or electrical components used in the operation of array 80 . It is to be noted and understood that such things as an electrical power generator is of substantial weight and could also act as an additional weight to assist in resistance of overturning moment and stability of base 10 .
[0069] In operation the invention works as follows. Base 10 would be pre-constructed. As mentioned, it is of a size that could be transported to a site by convention over-the-road transportation. Prior consideration would be made of the specific structure with which base 10 will be used. Sufficient weight in the form of, for example, of concrete 22 , additional weight 70 , or devices 84 and 86 would be sent along with base 10 , or available at the site.
[0070] Once at the site, base 10 could be manipulated by forklifts and other equipment to be placed in position on the ground or whatever other supporting surface is desired. Pre-determined add-ons such as weight or other devices or components would then be added to and attached to base 10 . Outriggers 16 would then be extended and feet 64 brought into contact with the ground. The jacks 60 would be adjusted to bring base 10 off the ground, usually to a level orientation. The base would then finally be configured appropriately based on the device to be supported, and then the device to be supported would be mounted onto the top of base 10 . In the foregoing example, a crane or some sort of a lifter device would raise pole 20 and array 80 vertically, move it over to above base 10 , and then bring it down and mount it to the top of base 10 . Any fine-tuning adjustment could be made, even after the structure to be supported (here pole 20 and array 80 ) is attached to base 10 .
[0071] In this example, a generator 84 is added into base 10 . The appropriate electric wires (in this example, pre-wired from array 80 down to the bottom of pole 20 ) could simply be electrically connected accordingly and the lighting array 80 could then be operated. It would be a self-contained lighting unit. The outriggers and weight in base 10 would have a pre-determined level of overturning moment resistance to handle whatever environmental standards exist for the site. This would include for certain configurations, winds on the order of 60 mph, or greater.
[0072] The apparatus operates on the physical principle that
Σμ=0 or(static equilibrium)= FL - WX
[0073] where μ is the sum of the moments, F represents the forces acting on the pole in a direction, L is the vertical distance from the top of the structure being supported to the ground, W is the total weight of the system, and X is the radius of Circle M, pictured in FIG. 3 (or the length of outriggers 16 ). From this equation, one could either determine how far apart the outriggers would be placed and then add weight to the system accordingly. Alternatively, one could determine the weight of the system, and then vary the distance of the outriggers. Both of these calculations would be made to withstand the maximum anticipated wind force. Static equilibrium is the condition where any more load to base 10 starts to heel it up.
[0074] The main variable is F, which is primarily wind loading. One can solve for any of the variables. Therefore, for any assumed wind load F, and any assumed outrigger extension X, the weight W needed to prevent overturning can be determined. Or for a given total weight, the length of outrigger can be determined.
[0075] The wind moment number is calculated based on standard building and structural codes for a particular configuration. Dividing the wind moment by the base moment arm results in the weight of the unit required to resist overturning. Since the operator or technician knows (a) the weight of his unit, (b) the fixture mounting height, (c) the number of fixtures, and (d) the EPA of the fixtures, he can determine from the charts what wind speed can be sustained based on his minimum moment arm (or outrigger) setting.
[0076] A booklet of charts can be produced which provides an operator with the information needed to set up the configuration to withstand certain winds. The charts would allow the operator to set the extension lengths of the outriggers and/or the amount of weight of the whole combination to meet the selected overturning resistance. The total weight would include the weight of everything associated with the base 10 , including the pole, the fixtures, the mounts for the fixtures, the fixture control mechanisms, electrical and electronic components, as well as the base 10 itself and anything inserted into the base 10 . For example, a 60′ tall pole can weigh 720 lbs., six (6) fixtures can weigh 150 lbs., controls and electrical components add 420 lbs. Base 10 can weigh on the order of 2,000-3,000 lbs. An electrical generator placed in base 10 could weigh on the order of 1,600 lbs. If outriggers are added, they could add 600 lbs. Then, if concrete add-on weights are added, they could add 7,200 lbs. to the total weight. See FIG. 16 for an example of the type of chart that could be prepared for a 60′ tall pole, withsix (6) fixtures.
[0077] The included preferred embodiment is given by way of example only and not limitation. Variations obvious to those skilled in the art are included within the invention which is solely described by the claims herein.
[0078] D. Options, Features And Alternatives
[0079] [0079]FIGS. 7 and 8 illustrate an alternative method of attaching a pole 20 to base 10 . In this example pole 20 is a hollow, tapered, steel pole. Tapered stub 90 can be concrete, steel, or other material. Stub 90 can be attached via a flange 98 to a plate similar to plate 68 previously described and fixed to base 10 . As illustrated in FIG. 7, pole 20 can be attached or detached from stub 90 simply by slip-fitting it over stub 90 or removing it therefrom. The weight of pole 20 and any attachments would keep it in place so no locking mechanisms are needed. Such an arrangement would be similar to that disclosed in U.S. Pat. No. 5,398,478 which is incorporated by reference hereto.
[0080] [0080]FIG. 8 shows pole 20 seated down on stub 90 . One advantage of this arrangement is that prior to seating onto stub 90 , pole 20 can be rotated around stub 90 to orient any elevated structure in a specific direction. This is especially valuable when aiming an array of lights in a certain direction.
[0081] [0081]FIGS. 9 and 10 illustrate another embodiment of a pole 20 . Pole 20 could be attached to base 10 by a number of different ways. In this embodiment pole 20 includes a lower section 92 attached to base 10 and an upper section 94 . Sections 92 and 94 are interconnected by a hinge 96 . Upper section 94 includes a tail 98 which at its very bottom further includes a weight 99 . As indicated by the arrow in FIG. 9, weight 99 helps upper section 94 pivot to a vertical position in normal use. Some sort of locking mechanism (not shown) could lock pole 20 in its normal vertical position (FIG. 10). However, if servicing or access to the top of pole 20 is desired, tail 98 could be released and the top of upper section 94 pivoted downwardly. This could be accomplished in a number of ways including some sort of a cable system. The use of weight 99 would allow for smooth, controlled pivoting.
[0082] Another method of use of bases 10 would be a plurality of bases 10 to support a larger structure such as shown in FIGS. 11 and 12. Each base 10 would support a corner of a vertical tower 106 (FIG. 11) or a scaffold 102 (FIG. 12). The scaffolds 102 in FIG. 12 in turn would support trusses 104 . Therefore, multiple bases 10 could provide temporary spread footings for a large super-structure.
[0083] As has previously been discussed, the intentional creation of openings or space between the top and bottom of the base 10 allows for any variety of interchangeable and removable inserts. They can be functioning components or simply weight.
[0084] With regard to weights 22 and 70 , it has been shown that a concrete block having steel facings on edges could be used. Alternatively, concrete with internal steel reinforcement like re-bar or re-rod could be used.
[0085] It could also be appreciated that weights such as weight 22 and weight 70 are inserted or recessed inside the perimeter of frame 10 so that they are inside the boundary of the overturning moment resistance. It also makes the weight closer to the center of the structure to make it easier for a forklift to lift and move the entire unit. This could occur with weights 22 and 70 attached to base 10 and even when a structure, such as a pole and light arrays is attached to base 10 .
[0086] Another option would be to add a running gear to base 10 so that it could be pulled like a trailer. On the other hand, as discussed, bases 10 can be placed in conventional over-the-road transportation and could even be stacked on one another or nested somehow. Slots such as slots 25 or hooks (see 71 in FIG. 2) could be built into weights 22 and 70 to make them easier to manipulate and move by forklifts and other equipment.
[0087] [0087]FIGS. 13, 14, 15 and 15 A illustrate an optional feature for outriggers 16 . Tubes 56 and 58 can telescopically extend from an end of base cross tubes 48 or 50 by nesting within one another as shown. A pivoting member or dog 160 is pivotable around pin 162 which is secured transversely across the proximal end of a longitudinal slot 164 in arm 56 . A similar slot 166 exits in arm 58 but without a dog. Pivot pin 162 can be held in place by a thin cover plate 163 (welded or otherwise connected to the exterior of tube 56 ).
[0088] Dog 160 and slots 164 and 166 cooperate to require that arm 56 be pulled out into and inserted from tube 48 or 50 first, that is relative to arm 58 . When arms 56 and 58 are fully extended, as shown in FIG. 13, dog 160 is pivoted up so that its edge 168 rides on top of the top outer side of arm 58 . Edge 170 of dog 160 therefore creates a stop disallowing arm 56 from being pushed into tube 48 . Arm 58 is free to be pushed into arm 56 . Therefore, when it is desired to retract arms 58 and 56 , dog 160 allows arm 58 to be retracted first until slot 166 of arm 58 aligns directly below slot 164 in arm 56 . When so aligned, the free end of dog 160 by gravity pivots down (see ghost lines 160 in FIG. 15) and dog 160 no longer blocks arm 56 from retracting into tube 48 .
[0089] Conversely, when arms 56 and 58 are retracted into tube 48 , because dog 160 extends through slots 164 and 166 , it requires that both arms 58 and 56 move out from tube 48 if either are pulled in that direction, until dog 160 clears tube 48 , at which point dog 160 would pivot up and allow arm 58 to retract from arm 56 .
[0090] Set-screws 172 and 174 in the side of arm 56 mate into cut-outs 176 and 178 in tube 48 when arm 56 is fully retracted into tube 48 and serve to disallow further inward movement of arm 56 . Set-screws 176 and 178 are also used to deter rattles between tubes 48 / 50 and arms 56 and 58 once positioned in place. Set-screws 180 and 182 in tube 48 also serve to deter arms 56 or 58 from moving once positioned. Arms 56 and 58 are disallowed from being completely pulled out and separating from its succeeding part by set-screws, but can be pulled completely out if needed for maintenance or replacement.
[0091] Further, a pre-determined system for installing base 10 relative to different structures it supports and environmental conditions could optionally be created. For example, through empirical testing, a chart could be created for poles of varying heights with varying numbers of light fixtures. The chart would indicate how much weight should be contained on base 10 and how far outriggers 16 should be extended to provide the appropriate resistance to overturning moment. It would also include the amount of necessary resistance to overturning moment based on an anticipated range of wind velocities. With this chart it would allow the installer and user of the system to configure base 10 to meet or exceed the needs for a particular use without having to do independent testing and without substantial over-compensating with regard to weight and extension of outriggers.
[0092] A leveling device or devices could be added to base 10 . In one simplistic form, level bubbles such as are used with carpenters' levels could be placed around the perimeter of base 10 . The operator could visually see when base 10 is leveled.
[0093] Operation of adjustable jacks 59 could enable the leveling. Note that jacks 59 could be manually vertically adjustable. Alternatively, as shown in FIG. 1, jacks 59 could have a hex nut (1½″) 140 over which fits a mating air wrench socket 142 . Operation of air wrench 144 would allow the operator to turn nut 140 which would raise or lower foot 64 of jack 59 . Still further, it is possible to have portable gear motors directly on jacks 59 which could be powered electrically to raise or lower jacks 59 .
[0094] Foot 64 could be 2′ by 2′ to diminish soil compaction.
[0095] For example, a chart (e.g. FIG. 16) would begin with certain assumptions, including, the type, configuration and height of pole, the number of light fixtures suspending at the mounting height of the pole, and the EPA (equivalent pressure area) of such the pole and fixtures when erected. Then, through testing or modeling, the wind load could be calculated for different extensions of the outriggers versus different total weight of the configuration. Appropriately graphed, the operator would be able to survey nearly any site for erection of the invention, and select the outrigger extension length and weight to resist overturning of the configuration for a given wind speed. Alternatively, the outrigger extension and amount of weight needed to be transported to the site of erection of the configuration could be pre-calculated at the storage location of the device. The necessary components could then be loaded on a truck, transported to the erection site, and then erected according to the predetermined settings.
[0096] There are times when the desired placement of the invention does not allow full extension of the outriggers. An example would be if the invention needed to be positioned next to a fence or building. Even if only one outrigger can not be extended to the length of the others, the resistance to overturning is decreased to that of the shortest extended outrigger. In this situation, more weight could be added to the invention to compensate for the restriction on outrigger extension.
[0097] On the other hand, the more the outriggers can be extended, the less total weight is needed. Therefore, there are times when less weight needs to be transported and manipulated to achieve the desired resistance to overturning.
[0098] Different charts can be created for different configurations (e.g. for different pole type/heights, difference fixture types/numbers, different EPAS, etc.).
[0099] Markings could be placed on the outrigger arms 56 , and 58 (see FIG. 1), which could match up with the charts. The operator would only have to look up the desired overturning resistance and extend the outriggers to the corresponding marking. For example, the markings could letters and/or numbers.
[0100] [0100]FIG. 16 is a depiction of such a chart 190 showing how heavy the total assembled base, pole, and elevated structure must be and how far the outriggers must be extended to support a 60′ light pole, withsix (6) fixtures attached to the pole, each fixture having an EPA of 4.0 at varying wind speeds. This example 190 shows that the indicia 192 (the data on the client) can quickly and easily be referred to by the used on-site and can therefore eliminate certain testing or experimentation that might otherwise be required. FIG. 16 illustrates generally a few different outrigger arm lengths and total system weight that could be used for a certain pole height, fixture type, fixture EPA, etc. Charts could be created for smaller increments and for different pole heights, number of fixtures, EPAs, etc. | An apparatus and method for providing a temporary spread footing for suppporting a variety of different vertically extending structures. The apparatus includes a frame with a top and bottom. The frame can have a substantial space or void in between the top and bottom into which weights or devices can be placed. A connection on top of the base removably connects to the structure to be supported. Outriggers could also be used to substantially increase the overturning moment resistance of the base. The outriggers can be removable or retractable so that for transportation, the base has minimum dimensions. The method includes pre-determining the needed weight and overturning moment resistance for a particular application and transporting the base to the site and thereafter adding weight and adjusting outriggers to match the pre-determined needed overturning moment resistance. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 61/116,957, filed Nov. 21, 2008, the entire contents of which are hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates to in-place soil stabilization. Specifically, the present invention relates a method and device for measuring the increase in subsurface earth pressure during the injection of a stabilizing agent into the soil. The rise in sensor pressure indicates an increase in soil strength and bearing capacity.
BACKGROUND OF THE INVENTION
[0003] The present invention relates a method and system for measuring the increase in compressive strength/bearing capacity for the soil which serves as a foundation for earth-supported structures such as buildings, roadways, pavements, and airport facilities.
[0004] Such earth-supported structures require that the underlying soil have sufficient bearing capacity to support the weight of the structure as well as the additional weight exerted onto the structures during usage (live loads). In order to design a stable and durable structure, an accurate assessment of bearing capacity is required.
[0005] The bearing capacity of the underlying soil is not always sufficient for the intended structure's design and use. Therefore, remedial measures to increase the strength/bearing capacity of the soil system is required. The resulting increase in bearing capacity due to the remedial method of injecting a stabilizing agent into the underlying soil mass may be determined using this invention.
[0006] Existing structures may also experience differential deflection or settlement due to unconsolidated soil strata, water infiltration, decomposition of organic materials, void conditions, poorly executed site preparation during original construction, additional live loads, soils consolidation from on-site vibration caused by equipment or traffic operations, et cetera. Such problems can be corrected by increasing the compressive strength of compromised soils. Until the present invention, there was no way to efficiently and accurately monitor the increase in soil strength/bearing capacity during remediation by soil injection.
[0007] Various conventional systems for remedial stabilization and/or lifting to correct structural settlement (including driven piles, piers, segmented cylinder piles, micro-piles, and other systems) rely on transfer of structural weight to deeper, more solid soils or rely on the skin friction between soils and the exterior surface of the pile itself to increase load-bearing capability. Such construction systems are invasive, disruptive, time consuming, and often unsuitable for pavements, lightweight slab, and other applications.
[0008] Conventional stabilization and/or lifting systems also include the method originally described in U.S. Pat. No. 4,567,708, which entails the injection of a polymeric material beneath a built structure to fill voids and to create a expansive force from the increase in volume caused by the chemical reaction of the polymeric substance. This system did not address the need for soil remediation as indicated by measurement of increased confined soil strength at depth.
[0009] Conventional stabilization systems also include the method described in U.S. Pat. No. 6,634,831, which is incorporated by reference herein in its entirety, and which entails the injection of a material through holes or tubes into the soil to produce compaction of the contiguous soil. This method requires constant surface monitoring to detect the exact moment at which the soil or the structure begins to lift upward. This system does not address the need to continuously measure and monitor, at depth, the amount of improved compaction of the targeted soil. This system does not monitor unknown and unexpected migration of the injectable material away from the injection site creating unexpected surface lifting some distance away from the desired location.
[0010] The “Method for Reducing the Liquefaction Potential of Foundation Soils” (PCT Application TR2003/000083 dated Nov. 5, 2003) also teaches the strengthening of soils using expansive polymers as indicated only by surface testing of the project's structural slab, using “laser beams,” which are presumed to be laser leveling systems. Such measurement fails to monitor and measure the precise confined soil strength at depth.
[0011] According to the Geotechnical Policy and Procedure manual produced by the Nebraska Department of Roads, a pressuremeter test may be used to determine the pressure at which the soil fails for a given depth. However, this test fails to be useful in determining the confined soil strength at a particular depth, and fails to provide a way to document evidence of confined soil pressures gained from the injection process.
[0012] The previously discussed patents teach only to monitor the surface for evidence of movement to indicate a sufficiency of injection material and soil strength. The previous systems fail to provide a system of monitoring and control in situ at depth and do not measure the differential, real-time increase in confined soil strength as the expanding polymer is introduced. The previous systems do not provide a means to document the strength gained from the injection process. Rather, the previous systems rely on monitoring for movement at the surface as a sort of proxy for what is occurring in the soil.
[0013] Previous methods have not met the need of providing in situ real-time soil strength data at various soil depths. Thus, previous methods also fail to indicate when geotechnical engineering specifications have been met or exceeded.
BRIEF SUMMARY OF THE INVENTION
[0014] The present invention solves the above problems by providing a method and device which permits real-time in situ measurement of soil strength at various depths. Consequently, the increase in soil strength can be monitored during the injection of the stabilizing agent into the soil.
[0015] In one embodiment, the present invention provides ongoing differential pressure change data taken from selected soil zone(s) both during the injection process and after completion of the process. Through the injection and monitoring of various substances, such as but not limited to expanding polymers, confined soil strength specifications can be achieved and assured. The invention can work with a variety of injectable substances, including but not limited to polymers, hydraulic systems, grout, cement, concrete, and chemicals.
[0016] While the present invention can work with a variety of systems, including hydraulic pressure systems, expanding polymer systems are preferred, in part because hydraulic pressure systems may sometimes cause the injected material to flow away from the targeted site.
[0017] The system disclosed herein provides engineers with a simple method to monitor and to document improvements in soil strength. This capability accommodates any desired safety margin for soil strength necessary to support present and future dead load and live load requirements.
[0018] The present invention uses small in situ pressure monitoring devices. Such devices can be hydraulic, pneumatic, or electric contact sensors. The pressure monitoring devices are placed in the soil near the injection site(s) to monitor the pressure at that location. One skilled in the art can select the location for strategic placement of such devices through tubes or drilled holes in the soil location chosen to monitor and achieve the desired soil strength improvement. The pressure monitoring device(s) may be placed above, below, or level with the injection site and may be laterally displaced from the injection site. Where more than one injection site is used, the device(s) may be placed between the sites, directly above or below each site, or any combination of the foregoing. The present invention is not limited to any particular location for the devices. However, such devices must be near enough to the injection site to measure pressure changes in the soil mass being stabilized.
[0019] Either before or after the pressure devices are in place, the stabilizing agent can be injected through small tubes or holes drilled from the surface and placed at desired depths and locations.
[0020] In some embodiments, the pressure sensor device is placed 20 feet, 10 feet, six feet, or three feet from the injection site. Other distances may be used, and the distances will depend on the particular job.
[0021] In weak soil, the injectable material (e.g., polymer) may move from the injection site and come into direct contact with the sensor. If this happens, the pressure sensor may give a false reading, thus preventing accurate measuring of the soil pressure. Therefore, in some embodiments, a thermocouple (temperature sensing probe) is provided at or near the pressure bulb to indicate if the injected substance has migrated onto the pressure sensor. In embodiments where the injected substance generates heat (e.g., expandable polymers), the thermocouple will quickly demonstrate through a temperature reading that the injected substance has contacted the thermocouple (and thus the device). Should this occur, injection of further material at that location is preferably stopped. The sensor is repositioned nearby (for example, approximately two feet away in any convenient direction), new injection tubes can be inserted, and injection of polymer is resumed.
[0022] As mentioned, it is within the scope of the present invention to monitor an increase in soil strength gain using any injectable substance known in the art. However, expandable polymers are preferred. Therefore, the remainder of this specification will generally refer to an embodiment with an expandable polymer, but the invention should not be limited to such.
[0023] Presently, the preferred reaction time for expansion of the polymer from liquid state to the expanded condition is less than one minute (30 to 45 seconds), though other reaction times may be used. In one embodiment, the short expansion time permits control of the injection process by allowing the injection technician periodically (typically every 5-20 seconds) to add more polymer into the soil strata to achieve greater expansive force and higher confined soil strength. When the desired confined soil strength is reached, as indicated by the pressure sensor, further injection is stopped and the material will cure and harden in place thus maintaining the new soil strength.
[0024] Where multiple injection sites are desired, an injection technician will then move to an adjacent site location and repeat the process of drilling holes, placing tubes, inserting a sensor, injecting polymer and monitoring the increased pressure results.
[0025] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] For a more complete understanding of the present invention, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
[0027] FIG. 1 is a profile view depicting holes drilled into soil according to one aspect of the present invention;
[0028] FIG. 2 is a is a profile view illustrating a pressure sensor tube and device lowered into a hole according to one aspect of the present invention;
[0029] FIG. 3 is a profile view depicting an advancer rod being used to push the pressure sensor device into the soil according to one aspect of the present invention;
[0030] FIG. 4 is a profile view illustrating a pressure sensor device in the soil and expanding polymer injected nearby, and includes an enlarged view of the device, according to one aspect of the present invention;
[0031] FIG. 5 is a schematic of a control box that can be used according to one aspect of the present invention;
[0032] FIG. 6 is a schematic of a pressure sensor device according to one aspect of the present invention;
[0033] FIG. 7 is a schematic of a soil density improvement system according to one aspect of the present invention;
[0034] FIG. 8 is a profile view illustrating a soil density improvement system according to one aspect of the present invention; and
[0035] FIG. 9 shows the geometrical arrangement of the injection tubes with respect to the tube containing the pressure and temperature sensor.
DETAILED DESCRIPTION OF THE INVENTION
[0036] The present invention can be used with one injection site or multiple injection sites. As an example of multiple injection sites, see U.S. Pat. No. 6,634,831, which has already been incorporated by reference in its entirety.
[0037] One or more holes are created by drilling, pressing, or vibration intrusion into compromised soil strata (less than desirable confined soil strength) subsurface locations. (See FIG. 1 ). As shown in FIG. 1 , polymer injection holes, 101 and 103 , and the sensor hole, 102 , are drilled into the weak soil zone. In some embodiments, the holes are ⅝″ in diameter. In other embodiments, the holes are spaced three to six feet apart.
[0038] Optionally, a tube may be placed in the one or more holes. Optionally, the lower tip of the tube is closed over with any device suitable for keeping soil from entering the tube. Non-limiting examples of such a device are tape or a small conical insert tip (i.e., made of metal or hard plastic). FIG. 2 shows a conical tip, 201 , inserted into the sensor hole, 202 . In some embodiments, the tube plus any optional tip is placed directly into the soil without a previous step of drilling a hole (i.e., the tube plus tip makes the hole).
[0039] Optionally, an advancer rod, 301 , (at least two inches longer than the tube, 302 ) is pushed into the tube to puncture or move the tape, 303 , or other device at the lower tip of the tube and create additional space in the soil for the sensor (i.e., an additional two inches is cleared beneath the tube). See FIG. 3 .
[0040] As shown in FIG. 6 , the pressure sensor assembly includes a sensor bulb, 601 , connected to a thermocouple wire, 602 , and flexible tubing lines, 603 . As shown in FIG. 4 , the pressure assembly, 402 , is inserted down the tube, 406 , or hole to position the sensor bulb beneath the bottom of the tube. In other embodiments, the pressure sensor is lowered simultaneously with the tube and optional tip, 405 . FIG. 4 also shows the control system, 401 , that monitors the expansive force of the polymer being injected through holes 404 and 403 . In other embodiments, the pressure sensor is lowered simultaneously with the advancer rod.
[0041] The upper ends of the thermocouple wire, 501 , and both tubing lines, 502 , are connected to the “Pump/Reservoir/Control Box” using “quick connect” insertion connections. The control box comprises a fill shut-off valve, 503 , an overfill vent, 504 , a vent shut-off valve, 505 , a temperature gauge, 506 , a pressure gauge, 507 , an air pump, 508 , and a liquid container, 509 .
[0042] In one embodiment, both the fill valve, 702 , and vent valve, 703 , of the control box, 704 , are opened and the air pump, 701 , is activated until the overfill vent line, 705 , flows with water (or any selected hydraulic fluid). Both the fill valve and vent valve are then closed. See FIG. 5 and FIG. 7 . Thus, the pressure sensing bulb, 706 , and flexible tubing, 708 , are filled with liquid. The thermocouple wire, 707 , is connected to the temperature gauge, 709 .
[0043] Continuous or timed intermittent injection of expanding polymer is then started at one or more locations, 801 and 802 , preferably adjacent tubes on opposite sides of the sensor tube location, 803 . Injection of the material continues until the pressure gauge on the control system, 804 , indicates the specified soil pressure has been achieved. See FIG. 8 .
[0044] In places having multiple injection sites, it may be desirous to arrange the tubes for injecting the expandable polymer in a geometrical configuration. For example, FIG. 9 shows injection tubes 906 , 907 , 908 and 909 arranged as a square. The injection holes will define the vertices or corners ( 901 , 902 , 903 and 904 ) of the geometrical shape. Tube 911 which contains a pressure sensor is located at the center ( 905 ) of the geometrical shape formed by the injection tubes. The geometrical shape may be any geometrical shape with an even number of vertices or any arrangement allowing the formation of one opposing pair. In this arrangement, each injection hole will have an opposing injection hole, forming opposing pairs of injection holes with a pressure hole in the middle. In FIG. 9 , injection tubes 906 and 908 form opposing pairs, and injection tubes 907 and 909 form opposing pairs. In some situations, the injection tubes are arranged in a linear formation forming a set of one opposing pair. A square arrangement has two sets of opposing pairs, and a hexagon arrangement has three sets of opposing pairs.
[0045] By placing the pressure sensor at various depths and in the middle of the opposing pairs of injection holes, an injection technician can monitor and adjust the amount of polymer being added to each injection hole to ensure soil stabilization within the entire volume of the geometrical shape. It may not be necessary or desirable to add the same amount of expandable polymer to each injection tube. For example, in FIG. 9 , it may be necessary to add more expandable polymer to injection tubes 903 and 902 than injection tubes 901 and 904 . The placement of the pressure sensor allows the injection technician to easily monitor and adjust the amount of polymer being added to stabilize an asymmetrical weak zone in the soil. In general, this type of soil stabilization does not produce a visual effect at the surface that indicates complete stabilization of the asymmetric weak zone. Therefore, it is necessary to monitor the soil stabilization in situ.
[0046] Injection of the polymer is stopped and the process is continued at nearby locations following the same procedure outlined above until the targeted soil strata have been sufficiently strengthened.
[0047] In other embodiments, the pressure sensor is not filled with liquid, but instead is filled with gas. In other embodiments, the pressure sensor is an electric contact device with pressure sensitive outer edges. When pressure pushes the edges inward to a pre-determined setting, an electrical circuit is completed that activates a signal on the surface (i.e., a light, bell, etc.).
[0048] The examples disclosed herein are included to demonstrate preferred embodiments of the invention. It should be appreciated by those of skill in the art that the techniques disclosed herein represent techniques discovered by the inventor to function well in the practice of the invention, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.
[0049] For example, a stabilization scenario where the present invention would be beneficial includes the stabilization of pavement on top of a base course made of uniformly-graded granular soil with poor compaction. In a specific embodiment, the pavement is Portland Cement Concrete (PCC) with a minimum slab thickness of six inches. The sub-grade underneath the base course is weak, fine-grained soil. The sub-grade is further divided into two distinct zones with the top zone being the soil that was compacted during construction and the bottom zone having weak, fine-grained soil with little to no compaction. The target zone for stabilization is the base course. Holes are drilled through the pavement and into the base course (the target stabilization zone). Injection tubes are placed in the injection holes with a tube comprising a pressure sensor located between the injection tubes. The stabilization agent is injected through the injection tubes into the base course thereby increasing the compaction of the uniformly-graded granular soil. In some embodiments, the stabilization agent is an injectable, two-component, expandable, high-density polyurethane foam (HDPF). In other embodiments, the HDPF is a free-rise material. In particular embodiments, the temperature of the HDPF coming out of the injection gun is between 100° F. and 130° F., 110° F. and 125° F., or 115° F. and 120° F. The density of the stabilization agent is between land 5 pounds/cubic foot, 1 and 4 pounds/cubic foot, 1 and 3 pounds/cubic foot, 1 and 2 pounds/cubic foot, 2 and 5 pounds/cubic foot, 3 and 5 pounds/cubic foot, 4 and 5 pounds/cubic foot, 3 and 5 pounds/cubic foot, or 3 and 4 pounds/cubic foot.
[0050] In some examples, increasing the density of the soil causes movement in the upper strata of the soil and this motion may damage the structural component supported by the soil if this motion is excessive. However, the excessive motion is also used to indicate that the soil has been sufficiently solidified by monitoring movement at the surface. Since this excessive motion at the surface may cause damage to structural components supported by the soil, it is desirous to monitor the movement of the upper strata of the soil at depth before causing any motion at the surface.
[0051] In some alternate and additional examples, the densification of the soil may be monitored using means in addition to the in-situ pressure sensor. For example, the densification of the soil may also be monitored in the upper strata using a vertical scale with an soil spike attached to the bottom of the vertical scale that is capable of penetrating the structural component and entering the soil at a depth of six to twelve inches. As the soil is being solidified, the technician can monitor the movement of the vertical scale to determine when the sub-surface soil has been solidified without causing movement of the surface and/or without causing unnecessary damage to structural components. In some examples, the soil spike attached to the vertical scale is made of a rigid material. The rigid material may be ceramic or metal. In specific examples, the object attached to the vertical scale is a nail. In particular examples, the nail is between six inches and three feet long or of a sufficient length to penetrate into the soil via a drilled hole through the built structure. If no structure is present on a soil site, the soil spike or nail attached to the bottom of the vertical scale can simply be inserted into the soil for monitoring at depth.
[0052] Thus, the invention can relate to any of the following:
A method of monitoring the remediation of weak soils from injection of expansive polymer by using a pressure sensitive bulb device placed at targeted subsurface soil strata to monitor the increase in confined soil strength at the selected location. A hydraulic pressure sensing device capable of being placed through drilled holes to any selected soil strata and depth, typically 50 feet or less. A miniature hydraulic pressure sensing device may be used at depths of 100 feet or more, depending on hole drilling and polymer injection systems. In this case, the length of the bulb itself would be increased to accommodate more hydraulic liquid and the flexible tube size would be increased to lower the inherent friction losses within the tubing which increases the accuracy of the pressure gauge to reflect the confined soil pressure at depth.
[0056] Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps. | The present invention relates to in-place soil stabilization. Specifically, the present invention relates a method and device for measuring the increase in subsurface earth pressure during the injection of a stabilizing agent into the soil. The rise in sensor pressure indicates an increase in soil strength and bearing capacity. Therefore, real-time monitoring of these pressures may serve as a guide during the injection process. | 4 |
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 14/548,211, filed Nov. 19, 2014, which is a continuation of U.S. patent application Ser. No. 14/069,256, filed Oct. 31, 2013, which is a continuation of U.S. patent application Ser. No. 13/611,188, filed Sep. 12, 2012, which is related to U.S. Provisional Application No. 61/533,936, filed Sep. 13, 2011, which is hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The field of the invention relates to systems and methods for data mining and processing, and more particularly to systems and methods for automating content from performance assessment data.
BACKGROUND OF THE INVENTION
[0003] Performance assessment data is an important aspect of the business, analysis, and appreciation of professional/fantasy sports, stock markets, mutual funds, personal fitness, student education, video gaming, consumer sales, and so on. Athletic teams, coaches, scouts, agents, and fans evaluate performance data and statistics for comparing the performance of teams and individual athletes. Game strategy and player potential are often based on predictive models using this data. Similarly, organizations and individuals evaluate corporate performance data to rank performance, reward good performance, and provide development assistance. Student test scores are also used to evaluate educational strategy; fitness and health statistics are monitored for efficient personal training; and financial charts are analyzed to alleviate stock risks. The advantages of data processing and analysis are well understood and appreciated. However, data processing and analysis is not always user friendly as understanding a large amount of structured data is a daunting task.
[0004] One approach for making sense of raw performance data relies on human expertise. For example, in the area of athletics, domain experts (e.g., coaches, scouts, managers, analysts, statisticians etc.) are typically relied on to effectively convert raw data into human readable/useful knowledge. Batting averages, field goal percentages, successive streaks are considered, inter alia, to determine success against certain players or potential against future opponents. Human domain experts can “humanize” this raw data and convert numbers and statistics into insightful prose/narrative. But, effectively analyzing performance data requires consideration of incredible amounts of information to reduce variable uncertainty. Bulk number crunching becomes a difficult task when the valuable insight is drowned in a sea of numbers and statistics. Therefore, this manual based approach to identifying performance metrics consumes both time and resources.
[0005] In another example, the popularity of fantasy sports has converted millions of fans into expert statisticians for scrutinizing a professional athlete's performance data. Fantasy leagues allow the virtual assembly of teams comprising actual athletes to compete with other virtual teams based upon those players' real-life performance. The sports and players represented through fantasy games are widespread. The number of applications providing fantasy leagues, often over the Internet, is similarly extensive. However, each may provide a unique way of scoring and rewarding player performance. Accordingly, the value of each player's performance data may vary across different leagues and sports.
[0006] Advancements in technology and computerized data processing have made a wealth of performance statistics readily available for coaches and fantasy owners alike to review. Individual player statistics may give insight to an athlete's speed, movement, skills, and agility against one or more opponents. However, processing this data and placing value on relevant statistics varies between managers, leagues, and sports. Manually digesting performance data can be cumbersome in light of the current number of statistical categories monitored. As the type and number of data collected increased, more practical methods were developed for useful volumetric data processing.
[0007] In one approach for volumetric processing of raw performance statistics, predictive modeling systems are used. Using a more automated approach to analyze a large quantity of data, an example modeling system associated with fantasy sports leagues is disclosed in U.S. patent application Ser. No. 12/111,054, U.S. Publication No. 2008/0281444 A1, filed Apr. 28, 2008, to Krieger et al. for a “Predictive Modeling System and Method for Fantasy Sports,” which is hereby incorporated by reference in its entirety. This system contemplates a predictive modeling engine for generating relationships among player data and provides projections based on the relationships.
[0008] However, current systems for predictive analytics typically generalize known patterns to new data for projecting player performances. Additionally, these predictive modeling systems rarely consider the unique priority various users place on certain data sets. The predictive results are typically as hard to digest and read as the raw data itself to the average human user.
[0009] In contrast to generalizing known patterns to new data, data mining emphasizes discovering previously unknown patterns in new data sets. Data mining has recently experienced growth in the area of performance assessment. Performance assessment benefits from discovering unknown strengths and weaknesses as opposed to assessing patterns of current performance. The advantages of domain experts (e.g., coaches, teachers, interactive gamers, and the like) in analyzing performance metrics are based on the inherent expertise of these individuals to detect unknown patterns through subjective approaches. Therefore, an effective method of automatically analyzing performance assessment data enhances alternative statistical evaluation with data mining to discover patterns that are systematically difficult to detect, especially when dealing with dynamic data sets.
[0010] Additionally, current systems modeling performance assessment may not provide results in a user-friendly manner, as discussed above. Supplemental tables and graphs are often created to reflect the results of predictive modeling and still require additional processing and analysis. Subjective priority is neither accounted for nor presented and additional steps of manual data processing required. Accordingly, an improved system and method for automated processing, categorizing, and presenting performance assessment data is desirable.
SUMMARY OF THE INVENTION
[0011] The field of the invention relates to systems and methods for data mining and processing, and more particularly to systems and methods for automating performance content from performance assessment data. In one embodiment, an automated notes and categorization system may include a primary database comprising performance assessment data. The primary database is operatively coupled to a computer program product having a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to execute a process that analyzes and converts raw performance data. The system further includes a processed database for storing the processed data operatively coupled to the computer program product for use with various user applications.
[0012] The process includes the steps of data mining said performance assessment data to obtain summarized data; prioritizing summarized data based on user-defined weight values for a plurality of classification categories; and converting results of the prioritization into plain language notes. The automated plain language notes will facilitate human understanding by presenting the data in narrative fashion.
[0013] Other systems, methods, features and advantages of the invention will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to better appreciate how the above-recited and other advantages and objects of the inventions are obtained, a more particular description of the embodiments briefly described above will be rendered by reference to specific embodiments thereof, which are illustrated in the accompanying drawings. It should be noted that the components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views. However, like parts do not always have like reference numerals. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated schematically rather than literally or precisely.
[0015] FIG. 1 is a schematic diagram of a data processing system for use with performance assessment data according to one embedment of the present invention.
[0016] FIG. 2 is a flowchart of an electronic process in accordance with a preferred embodiment of the present invention.
[0017] FIG. 3 is a flowchart further detailing the electronic process shown in FIG. 2 in accordance with a preferred embodiment of the present invention.
[0018] FIG. 4 is another flowchart further detailing the electronic process shown in FIG. 2 in accordance with a preferred embodiment of the present invention;
[0019] FIG. 5 a is an example of a user interface for a football application of the performance assessment application;
[0020] FIG. 5 b is another example of a user interface for a football application of the performance assessment application;
[0021] FIG. 6 is another flowchart detailing another electronic process in accordance with a preferred embodiment of the present invention;
[0022] FIGS. 7 a - g are other examples of user interfaces of the performance assessment application; and
[0023] FIG. 8 is another example of a user interface of the performance assessment application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] As described above, an incredible amount of performance assessment data exists across a number of domains of athletics, interactive gaming, physical fitness, finance, and so on. Evaluating this performance data for decision-making criteria is an integral part for seeking a competitive edge in each of these domains. Turning to FIG. 1 , an exemplary system 100 is illustrated to make sense of raw performance data and convert said data into actionable knowledge, according to one embodiment of the present invention. The system 100 has a processing application 101 that is communicatively coupled to primary data source 102 . As is known in the art, processing application 101 may represent a computer, which includes a computer-usable storage medium, such as in a server, having sequence of instructions which, when executed by a processor, causes said processor to execute a process that converts raw performance data into information that is both digestible and prioritized.
[0025] The processing application 101 may further include a user interface console, such as a touch screen monitor (not shown), to allow the user/operator to preset various system parameters. User defined system parameters may include, but are not limited to, assigning categorical priorities, assigning priority weights, adjusting time-frame analysis, and setting split variables.
[0026] In one embodiment, primary data source 102 is used for the storage of primary performance assessment data. For example, National Football League (NFL) statistics, Major League Baseball (MLB) statistics, stock market data, personal fitness goals, and other performance data may be stored within data source 102 . The data may be historical or live (real-time) data. In an alternative embodiment of the present disclosure, an optional secondary data source 103 is communicatively coupled to processing application 101 . Accordingly, the performance data provided to application 101 is not limited to primary performance data and may optionally include user-generated (or secondary) data, which is generally defined as performance data that is based on the primary performance information. An example of secondary data includes the performance of a fantasy football or baseball team. As fantasy participants claim players off of waivers, alter lineups, make draft decisions, and watch their fantasy teams perform, user-generated/secondary data is produced to assess the performance of the fantasy team and players based on the primary performance data reflecting the actual player statistics. Another example user generated performance data includes stock market simulation games, where users play with pretend investment dollars.
[0027] As those of ordinary skill in the art would appreciate, primary data source 102 as well as secondary data source 103 may be any type of storage device or storage medium such as hard disks, cloud storage, CD-ROMs, flash memory and DRAM. In other embodiments, it should be understood that processing application 101 , primary data source 102 , and secondary data source 103 could reside on the same computing device or on different computing devices. Similarly, the performance data of primary data source 102 and/or secondary data source 103 could be stored within the processing application 101 or some other accessible server or data storage device.
[0028] The system 100 further includes a processed database 104 coupled to the processing application 101 for storing processed data results of the application 101 . Similar to data sources 102 / 103 as discussed above, database 104 may be any type of storage device or storage medium such as hard disks, cloud storage, CD-ROMs, flash memory and DRAM. The database 104 can also reside on the same computing device as data sources 102 / 103 , processing application 101 , or some other accessible server or data storage device. Both processing application 101 and database 104 are accessible over data network 105 . Data network 105 can pertain to a global data network (e.g., the Internet), a regional data network, or a local area network. Furthermore, the network 105 can also include one or more wired or wireless networks.
[0029] User platform 106 accesses the services provided by processing application 101 as well as the processed performance data stored in database 104 via network 105 . Platform 106 represents a variety of local or online applications where performance assessment is involved. Some examples include, but are not limited to, professional sports, fantasy sports, interactive gaming, physical fitness, social networking, stock markets, mutual funds, educational evaluation, and consumer sales.
[0030] A user, or plurality of users, 107 of user platform 106 accesses the performance assessment data using client devices, for example 107 A, 107 B, 107 C and 107 N, over data network 105 . These client devices may be computing devices such as laptops, desktops, cellular phones, personal digital assistants (PDA), set top boxes, and so on. Communication with the data network 105 can occur through a network data link, which can be a wired link and/or a wireless link. As is well known in the art, one or more of the users 107 may also communicate with the processing application 101 or processed database 104 directly.
[0031] Data sources 102 / 103 are configured to store one or more elements of raw performance data. However, as discussed above, as the number of statistical data stored increases, converting the data to useable knowledge can be time consuming and resource inefficient. Predictive models based on raw data must still be evaluated and, often, are not easily understood.
[0032] One approach to address this issue is shown in FIG. 2 , which illustrates a process 2000 that may be executed by system 100 . Process 2000 begins with raw performance data (starting block 2010 ), such as the data maintained in data sources 102 / 103 .
[0033] This raw data subsequently undergoes three major processing steps: (1) data mining (action block 2020 ); (2) category prioritization (action block 2030 ); and (3) nuggetization (action block 2040 ). As a result of process 2000 , automated notes are created from the raw data that facilitates performance assessment in a user-friendly approach.
[0034] In order to harness a wealth of raw performance information, process 2000 uses data mining techniques to process and summarize raw data (action block 2020 ). With reference now to FIG. 3 , start block 3010 begins by collecting raw data associated with performance assessment and populating the Primary Data Source 102 (action block 3020 ). Current systems and methods exist for acquiring, collecting, exporting and delivering performance assessment data. Furthermore, real-time performance data can be delivered, for example, using real-time locating systems (RTLS) and real-time sensing systems (RTSS) with RF technology. Local data can be acquired using sensors to measure physiological parameters as well as other empirical data. Additional information on data acquisition/collection methods and techniques can be found, for example, in U.S. Pat. No. 7,689,437 to Teller et al., filed Jun. 16, 2000 for a “System for Monitoring Health, Wellness and Fitness,” and U.S. patent application Ser. No. 12/772,599, U.S. Publication No. 2010/0283630, filed May 3, 2010, for “Sports Telemetry System for Collecting Performance Metrics and Data,” both of which are incorporated by reference herewith in their entirety. Although other methods for collecting data are available, existing databases compiled with performance assessment data may also be used from known services, such as, the Associated Press (AP), ESPN, Stats, Inc., Sports Data, Google Finance and Yahoo Finance, etc.
[0035] Once the raw data is available for processing, process 2000 subsequently summarizes the raw data into predefined categories for further processing (action block 3030 ). Using the sport of football as an example, this raw data is summarized into two categories: (i) Statistics (e.g., pass attempts, completions, touchdowns, etc.) for players and teams; and (ii) Splits (e.g., by time-frame, opponent, side of field, time of game). Table 1 illustrates another example using baseball where raw data from Data Source 102 may include information about a single player's at-bat:
[0000]
TABLE 1
Primary-
GameID
PlayerID
BSCount
PitchType
PitchResult
Event
Etc.
22232
99921
0-0
1
Missed
22232
99921
0-1
1
Ball
22232
99921
101
2
Well-Hit
GO
[0036] Each pitch of a single at-bat in Game 22232 for Player ID 99921 is shown in Table 1. Summarizing this raw data in action block 3030 , Table 2 illustrates an example of summarized data for three players over one game whose raw data is similar to that shown in Table 1:
[0000]
TABLE 2
Date
PlayerID
Hits
At-Bats
Walks
RBI
E
Jun. 11, 2011
99921
1
4
1
1
Jun. 11, 2011
99923
0
3
0
0
Jun. 11, 2011
99926
2
3
1
2
[0037] This summarized data is stored in processed database 104 (action block 3040 ). Once the processed database is populated with summarized data, the data is then filtered and prioritized (action block 3050 ). Irrelevant or least relevant data is removed and relevant data is flagged and assigned priority values (i.e., weight values) within defined categories. Turning to FIG. 6 , an illustration of a process 5000 for filtering and prioritizing the data is shown. First, for each category, the sample size is assessed to determine whether the sample size is sufficiently large to provide meaningful analysis, e.g., if the sample size meets a pre-defined threshold (Action Block 5010 ). For instance, in the case of batting averages, players are grouped based on number of at-bat attempts in top, middle, and bottom tiers:
Bucket 1=subjects ranking in the 60 th percentile or higher attempts Bucket 2=subjects ranking in the 16 th -59 th percentile in attempts Bucket 3=subjects ranking in the bottom 15 th percentile in attempts
[0041] In this example, the players in “Bucket 3” are excluded from further analysis due to insufficient sample size. The data within each bucket is then ranked (Action Block 5020 ). An illustration of filtering and ranking is shown below:
[0000]
Player
BAVG
AB
BAVG Rk
Bucket
Bucket Pcntl
McCutchen, Andrew
.362
417
1
1
100
Kemp, Matt
.358
240
2
1
99.5
Smoak, Justin
.189
344
232
1
0.4
Buck, John
.184
277
233
1
0
Ciriaco, Pedro
.337
89
1
2
100
Dirks, Andy
.333
168
2
2
99.4
Coghlan, Chris
.140
93
172
2
0.5
Conrad, Brooks
.133
98
173
2
0
Perez, Hernan
.500
2
1
3
100
Carrera, Ezequiel
.414
29
2
3
99.4
Bianchi, Jeff
.000
13
161
3
0
Vogt, Stephen
.000
17
161
3
0
[0042] Another example of ranking data, using the examples provided in Tables 1 and 2 above, is presented in Table 3:
[0000]
TABLE 3
Ovrl At-
Ovrl
Hits-
AB-
BAVG-
PlyerID
StrtDate
EndDate
OvrlHits
Bats
Hits Rk
fastball
fastball
FB Rk
99921
Jun. 1, 2011
Jun. 11, 2011
6
18
190
6
12
10
99923
Jun. 1, 2011
Jun. 11, 2011
11
35
3
8
29
36
99926
Jun. 1, 2011
Jun. 11, 2011
2
21
281
1
15
265
99935
Jun. 1, 2011
Jun. 11, 2011
0
1
450
0
1
450
[0043] In this example, the players are ranked according to both their overall batting average (i.e., the ratio of total hits versus total at-bats) as well as their fastball batting average (i.e., the ratio of hits versus fastballs at-bats). As Table 3 also illustrates, the data is not only summarized using statistics (e.g., at-bats and hits), but also using splits (e.g., time-frame split reflecting only games between Jun. 6, 2011 to Jun. 11, 2011). A plurality of ranked tables covering various timeframes and splits for the summarized data is created (not shown) similar to Table 3. This plurality of ranked data is then stored in Processed Database 104 (action block 3060 ) for use with category prioritization (end block 3070 ). As will be demonstrated below, this information will enable the system 100 to generate noteworthy data and trends not provided by previous systems known in the art.
[0044] Turning back to FIG. 2 , category prioritization (action block 2030 ) classifies performance data using application specific schemes. Generally, in one embodiment, the standard classification schemes include seven categories: (1) granularity; (2) sample size significance; (3) performance extremes; (4) positive/negative impact; (5) circumstantial significance; (6) performance or tendency; and (7) comparison between timeframes. This classification scheme can also vary based on user input to processing application 101 .
[0045] Applying this standard scheme to baseball, for example, (1) granularity indicates the level of detail for a specific statistic. For instance, the more splits, the more granular. Further, the lower average denominator for a category, the more granular the category tends to be. Some categories may be granular by nature, e.g., miss percentage of swings may be more granular than overall batting average. Further, overall batting average would not be as granular as fastball batting average in the example above. (2) Sample size significance determines the relevance of each category based on the sample size (“attempts”), such that 250 overall at-bats are more significant than 120 overall at-bats. For instance, in the “Bucket” example above, sample size significance is illustrated below:
[0000]
Bucket 1 Minimum
Bucket 1 Max
STAT (Category)
Denominator
Denominator
Overall Batting Average
240
488
Fastball Slugging Percentage
160
320
Breaking Ball Miss Percentage
223
465
Changeup Batting Average
87
125
[0046] Sorting the list above by column 2 (the minimum denominator to qualify as Bucket 1 as described previously) would effectively provide the sample size significance value. If the user chose to only view data with high sample size, then likely the categories Fastball Slugging Percentage and Changeup Batting Average in the table above would be excluded from the search results.
[0047] (3) Performance extremes identifies the statistically best and worst for each category (e.g., league leaders in batting average and the league worst in batting average have higher performance extreme values compared to those in the league in or around the average (50th percentile)). (4) Positive/negative impact reveals the influence of data to the performer (e.g., a 0.500 batting average against fastballs is positive to the player whereas a 0.100 batting average against fastballs is negative). Two factors will determine this in baseball statistics: whether a high number is good and what percentile the player falls into for that category. (5) Circumstantial significance reveals the influence of data in relation to circumstantial variables (e.g., notes and data regarding an upcoming opponent). This considers both the current state and the history state, such as opponent strength, weather, and whether a team is home or away.
[0048] (6) Performance or Tendency: this category makes a distinction between whether the Stat (Category) is performance based or technique/strategy based. For example, batting average is performance measure, but Curveball Usage for a pitcher or Pass Attempt % of Plays for a football team are more tendency or technique based.
[0049] (7) Comparison Between Timeframes: with this category, data between different time frames may be compared. Under this category, the prioritization may be based, at least in part, on the differences between those time frames. For example, for Albert Pujols, if 2011 and 2012 are selected as compared ranges, under other prioritization schemes, priority of data may be based on comparison against league normal data. However, under this scheme, higher priority may be given to stats/data where Pujols 2012 is significantly different from Pujols 2011.
[0050] Category prioritization determines which information from the database 104 is relevant to a certain category and is then assigned a priority value within that category. For instance, from Table 3 above, Player 99921 is ranked 10th in the league in batting average versus fastballs since Jun. 1, 2011. This relevant data is flagged and assigned a note strength value for this category as shown in the table below:
[0000]
Player 9921 (BAVG-“Batting Average”)
Beginning
Size
Note
Size
Percentile
Strength
Split
Bucket
Strength
Stat-Split Category
Timeframe
Bucket
Rank
Value
Adjust.
Adjust.
Value
BAVG High Pitches
1
1
10
80
x
1
x
1
80
BAVG Fastball
1
1
90
80
x
1
x
1
80
SLG High Pitches
1
1
12
78
x
0.1
x
1
7.6
BAVG Pitcher Ahead
3
1
30
40
x
1
x
1
40
BAVG LHP
1
2
44
12
x
1
x
0.5
6
Miss% Fastball
4
1
52
4
x
1
x
1
4
GB% Overall
1
1
88
73
x
1
x
1
76
Etc. . .,
[0051] Note Strength Value is determined by a formula that considers the following three factors: 1) Percentile ranking for that stat category; 2) Sample size Bucket; and 3) the type of Split.
[0052] Beginning Strength Value=ABS(50−Percentile Ranking)*2. The highest possible strength value=100.
[0053] Split adjustment becomes 0.1 (or other value) multiplier through code that knows whether a stat category with the same split has already been given a higher Note Strength Value. For example, in the above table, this hitter ranks poorly (10th and 12th percentile, respectively) in two very similar Stat-Split categories: BAVG and SLG vs. “High Pitches”. The program would apply a Split Adjustment to the SLG vs High Pitches to reduce its Note Strength Value because BAVG vs High Pitches already has a high Note Strength attached to it (80).
[0054] Size Bucket Adjustment can be used to reduce the Note Strength for stat categories where the subject falls into Size Bucket 2 or 3, meaning they do not have a significant sample size as those who were in Bucket 1 did.
[0055] Thus, in summarizing the table above, the two stat-split combinations with the highest Note Strength Values are: Batting Average against High Pitches and Groundball Percentage Overall. SLG vs. high pitches is a significant weakness for this player, but it's note value drops because his BAVG on high pitches is already higher in note priority. Categories such as BAVG LHP and Miss % of Fastball have low Note Strengths because the player was near the league average (near 50th percentile) in those areas.
[0056] Once the remaining flagged items are assigned categorical priorities, process 2000 then converts (a.k.a., nuggetizes) the remaining filtered/prioritized data to text strings (action block 2040 ). With reference to FIG. 4 , the data remaining in processed database 104 is obtained, each flagged data entry having a categorical priority value (start block 4010 and action block 4020 ). This data is converted to phrases (action block 4030 ) and these phrases are then processed into sentences (action block 4040 ), which can also be referred to as AutoNotes. These automated sentences are much more readable than the summarized data. The sentences are based on predefined strings. For example, for the metric, fastball first pitch taken percentage, the string would read as follows:
“Has taken your first pitch FB <Notable Zone><Numerator Notable Zone> of <Denominator Notable Zone> times”. Thus, for notable data in this category, the output would be generated as follows: “Has taken your first pitch FB Down/Away 31 of 31 times.”
[0058] Below are some additional examples using Joe Mauer v. Right Handed Pitchers:
Strength—Fastball (0.374) especially on first pitch (0.538). Changeup (0.288) especially when he's ahead (0.333). Best 2-strike pitch is CH/OT Middle/Down (0 well-hit out of 10 strikes) Has taken first-pitch FB Down/Away 31 of 34 times Has not chased FB when thrown Middle/In (only 3 chased of 25 out-of-zone pitches) Weakness—CH/OT has been effective when Middle/Middle (0 well-hit of 8 strikes)
[0064] Other examples using the data above produces sentences for player 99921 and player 99926:
“Nationals outfielder Joe Smith is 6-for-18 (0.333 batting average) since June 1.” “Joe Smith of the Nationals is batting 0.500 (6-for-12) against fastballs since June 1.”
[0067] “Bob Jones of the White Sox has only 2 hits in his last 21 at-bats.” As aggregate data (e.g., league average, national average, etc.) is also available, additional information may also supplement the sentence created in action block 4040 (action block 4050). For example, appending related batting average assessment for the league produces: “Joe Smith of the Nationals is batting 0.500 (6-for-12) against fastballs since June 1; the league average against fastballs is 0.282.”
[0068] Each of these text strings and their associated priority values for each category are then stored in a separate database (not shown) (action block 4060 ). Alternatively, the text strings and their priority values may also be generated as needed. An example of stored text strings is illustrated in Table 5:
[0000]
TABLE 5
Sample
Perf.
Special
+/− to
Subject
Note
Granularity
Size
Extreme
Signif.
subject
Joe
Joe Smith is 6-for-18 (0.333
1
7
7
0
9
Smith
batting average) since June
1.
Joe
Joe Smith is batting 0.500
7
8
9
0
10
Smith
(6-for-12) against fastballs
since June 1.
Joe
Joe Smith is batting just
6
9
10
10
1
Smith
0.100 (2-for-20) against
tonight's opposing starter.
[0069] The presentation of such data can be configured in a variety of ways. For instance, an AutoNote can be generated for an individual as part of a specific group. For example, an AutoNote can be generated for his performance on his particular team: “Joe Smith leads all Twin hitters with 20 HRs.”
[0070] The AutoNote may also reflect personal and/or team improvements. For example: Student X is averaging 90% on his geometry tests since December 1, when he was averaging 69% on his previous tests.” Or “the Angels are batting 0.320 against breaking pitches in 2012 whereas they were batting 0.200 against breaking pitches in 2011.”
[0071] Trends and tendencies may also be presented in AutoNotes. For example, in the education setting, the system 100 can generate the following AutoNote: “Student X earned a score of 90% or better in 8 straight test grades.” In football, an AutoNote may generate: “Running Back Frank Gore has run over 100 yards in 7 straight games.” A trend may also be presented in the negative based on the noteworthy data above: “Derek Jeter has not hit a fastball in the last 10 games.” Further, the dates of these trends and tendencies may be configured. For example, a user may select 2011 and 2012 such that the AutoNote generates: “Derek Jeter batted 0.160 versus right-handed breaking pitches in 2011 and batted 0.270 against right handed pitches in 2012.” Moreover, the data generated from these two different timeframes may be compared and the data may be presented based at least in part on the “Comparison Between Timeframes” category prioritization scheme described above.
[0072] This data can then be used with a variety of user platforms 106 (end block 4070 ). For example, AutoNotes can be utilized with Twitter, Facebook messaging, or other social media and messaging platforms. AutoNotes enables the system 100 to discover and present note-worthy pieces of information about a performer, such as a player, a student, a company, or team, using user friendly language.
[0073] Referring to FIGS. 5 a - b , additional sample user interfaces demonstrate the use of processing application 101 . As illustrated, user platforms may be interactive such that users may search and research rather than viewing summaries and recaps. Searching for automated notes in a single player is illustrated in FIG. 5 a , while searching for automated notes reflecting an entire team/league is illustrated in FIG. 5 b.
[0074] Turning to FIGS. 7 a -7 g , exemplary applications of AutoNotes are shown. AutoNotes may be particularly suitable for popular fantasy sports leagues, where stats are crucial to users of the leagues. AutoNotes can be used to critique user actions in the form of Auto Smacks, shown in FIG. 7 a or High-5s in FIG. 7 b or Triumphs and Failures in FIG. 7 e , or as general notes, as shown in FIG. 7 c or as trade suggestions in FIG. 7 d . AutoNotes can also be used for Report Cards, as shown in FIG. 7 f or team ratings, as shown in FIG. 7 g.
[0075] Turning to FIG. 8 , a “drill down” feature may be added to an AutoNote application, which enables a user to drill down on a particular AutoNote for additional information. For example, for the AutoNote, “Tom Brady has completed 80% of his passes in the last 3 games,” a button or click event can trigger either more notes related to that, or a table of information. For example: In the last 3 games: 90% completions to running backs; 71% to Tight Ends; 64% to Wide Receivers; 88% to left side; 77% to middle of field; 59% to right side, etc . . .
[0076] Although the previous embodiments were discussed primarily using athletic performance assessment data, those skilled in the art would appreciate that alternative platforms 106 may benefit from processing application 101 . This may be shown in the following examples:
EXAMPLE 1
[0077] Using weight loss/physical fitness, category prioritization (action block 2030 ) may apply the standard classification scheme to physical fitness assessment data. Granularity places priority on notes according level of detail: high granularity (e.g., routine workouts to generate “Susan has burned an average of 200 calories while bike riding on Sundays in the past 10 weeks.”); medium granularity (e.g., time-frame split diet to generate “Susan had 8 servings of vegetables since last Tuesday.”); and low granularity (e.g., single performances to generate “Susan ran 2 miles today.”).
[0078] Sample size significance classifies notes as follows: highly significant sample size (e.g., with a sample size of one year, “Susan has lost 30 pounds (25 percent of her starting weight) in the last 365 days.”); medium sample size significance (e.g., with a sample size of a month, “Susan's weight has decreased from 140 pounds to 135 pounds this month.”); and low sample size significance (e.g., single day to generate “Susan did not exercise today.”).
[0079] Performance extremes classifies notes as follows: highly extreme (e.g., superlative ranking, “Susan ranks 1st among her friends in percentage pounds lost in October (2% loss).”); medium extreme (e.g., “Susan's ranks 7th among her 15 friends in percentage weight lost since September (0.8% loss).”); and low extreme (e.g., average performance, “Susan ranks in the 50 th percentile among users of this application with an average of 1 serving of fruits per day this week.”).
[0080] Using a time-based circumstance, an example of highly circumstantial significance to a single day: “Susan's toughest day for exercise is Wednesday. Try to get out there today (Wednesday) Susan!” Classifying notes having a positive/negative impact includes: positive impact to fitness (e.g., “Susan lost 30 pounds (25 percent of her starting weight) in the last calendar year. Way to go Susan!”); and negative impact (e.g., “Susan has not exercised in the past 3 days.”).
EXAMPLE 2
[0081] Using interactive gaming (e.g., online video poker), category prioritization (action block 2030 ) may apply the standard classification scheme to gaming assessment data. Granularity places priority on notes according level of detail: high granularity (e.g., specific event to generate “You have averaged +20 credits when being dealt a pair of sevens or lower this month. The average player is even.” or “User has hit the green 18 of 20 times with his drive on the par-three 18th hole at Sawgrass in Tiger Woods Golf.”); medium granularity (e.g., less detailed event to generate “You have been dealt a pair 30 percent of the time this week. The average player is dealt a pair 20 percent of the time.” or “You have won the last 4 times you played John Smith and used Roy Halladay as your starting pitched in MLB The Show.”); and low granularity (e.g., general detail to generate “You averaged −25 credits this week.” or “You have won the last 4 times you played John Smith in Modern Warfare II.”).
[0082] Sample size significance classifies notes as follows: highly significant sample size (e.g., multiple attempts, “You won 295 hands and lost 304 hands since June 1. That 49.2% winning hand percentage ranks in the 10th percentile among players of this game.” or “Your overall record is 43 wins and 20 losses in Madden Football over the past calendar year.”); medium sample size significance (e.g., mid-size sample, “You won 10 of 20 times today when being dealt an Ace with no pair.” or “Your defense is allowing just 2.2 yards per carry in Madden Football in the past 15 games.”); and low sample size significance (e.g., a few events “You have only 1 win in the last 10 hands.” or “Your team has averaged 360 yards passing in the last 3 games of Madden Football.”).
[0083] Performance extremes classifies notes as follows: highly extreme (e.g., superlative ranking, “Between June 1 and June 15, your total winnings are +3000.” or “Your record is 0 wins and 20 losses in Grand Theft Auto.”); medium extreme (e.g., “You received a 3-of-a-kind 12 times in 65 hands (18%) when being dealt a pair. The average player gets 3-of-a-kind 14% of the time.” or “Your record is 12 wins and 8 losses in Grand Theft Auto.”); and low extreme (e.g., average performance, “Your record is 10 wins and 10 losses in Grand Theft Auto.”).
[0084] Classifying notes having a positive/negative impact includes: positive impact to game strategy (e.g., “You were dealt a Big Hand (straight or better) 10 times in the last 125 deals for a gain of 1250.” or “Your pitchers are averaging 11 strikeouts per game (normal average is 6 per game) since Jun. 1, 2011 in MLB the Show.”); and negative impact (e.g., “You have a current streak of 7 straight days with negative earnings, totaling −950.” or “Your pitchers are averaging 3 strikeouts per game (normal average is 6 per game) since Jun. 1, 2011 in MLB the Show.”).
EXAMPLE 3
[0085] Using finance, category prioritization (action block 2030 ) may apply the standard classification scheme to stock market assessment data. Granularity places priority on notes according level of detail: high granularity (e.g., specific stock event “The most volatile stock in the S&P 500 in the past 60 days has been Netflix (NFLX), with a high of 242 and a low of 129 in that timeframe.”); medium granularity (e.g., smaller time split “Citigroup (C) stock has risen 2.9% in the last 30 days; the rest of the banking sector is down −12.3%.”); and low granularity (e.g., general stock trend “Shares of Verizon (VZ) are down 9 percent since May 1.”).
[0086] Sample size significance classifies notes as follows: highly significant sample size (e.g., “Southwest Airlines (LUV) stock has been positive 210 days and negative 103 days in the last calendar year”); medium sample size significance (e.g., “The biggest large-cap gainer in tech stocks in the past 120 days has been Cypress Semiconductor (CY) with a 25.6% increase.”); and low sample size significance (e.g., “Shares of Bank of America (BAC) have risen 10 percent in the last three days.”).
[0087] Performance extremes classifies notes as follows: highly extreme (e.g., superlative ranking, “If you purchased 100 shares of Apple (AAPL) on Jan. 1, 2011, you have made $1,000 profit (+69%) as of today.”); medium extreme (e.g., “If you purchased 100 shares of PepsiCo (PEP) on Jan. 1, 2011, you have made $20 profit as of today (+0.02%).”); and low extreme (e.g., average performance, “If you purchased 100 shares of Nokia (NOK) on Mar. 1, 2011, you've lost $1,605 (−105%) as of today.”).
[0088] Using a time-based circumstance, an example of highly circumstantial significance to a single day: “Following a 4% or more price decrease such as yesterday's, General Electric (GE) tends to rise 3.2 percent the following day (9 such occurrences).” Classifying notes having a positive/negative impact includes: positive impact to investment strategy (e.g., “Wal-Mart (WMT) has gained 20.2 percent in the past six weeks.”); and negative impact (e.g., “Home Depot (HD) is down 18 percent in the past six weeks.”).
[0089] In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. For example, the reader is to understand that the specific ordering and combination of process actions described herein is merely illustrative, and the invention may appropriately be performed using different or additional process actions, or a different combination or ordering of process actions. For example, this invention is particularly suited for athletic-based performance assessment data, such as fantasy sports; however, the invention can be used for any performance assessment data. Additionally and obviously, features may be added or subtracted as desired. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. | The field of the invention relates to systems and methods for data mining and processing, and more particularly to systems and methods for automating content from performance assessment data. In one embodiment, an automated notes and categorization system may include a primary database comprising performance assessment data. The primary database is operatively coupled to a computer program product having a computer-usable medium having a sequence of instructions which, when executed by a processor, causes said processor to execute a process that analyzes and converts raw performance data into automated content that presents data in readable user friendly form to facilitate human understanding. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a twisting apparatus for ultrafine rectangular bar whose cross section is formed in a rectangular shape such as a triangle or square to be formed in a spiral shape upon twisting the ultrafine rectangular bar.
[0003] 2. Description of Related Art
[0004] In dental treatments, while a surface of a calcified root canal wall is cut, cutting debris or contents filled in the root canal are removed to expose a new surface of the root canal wall and to form the root canal. Endodontic devices including files and reamers having different diameter sizes are provided as instruments for forming such root canals. Some of those files and reamers are provided in having a rectangular cross-sectional shape and different diameter sizes, which are selectable according to the procedure of the treatment.
[0005] For example, a K-file is provided in having a cross section in a triangle or square shape, having a work portion formed in a spiral shape with a relatively narrow pitch made by a twisting process, and having a function to shave the root canal wall mainly upon pushing and pulling manipulations and to remove the shaved debris and contents. A reamer is provided in having a cross section in a square shape, having a work portion formed in a spiral shape with a relatively wide pitch made by a twisting process, and having a function to shave the root canal wall mainly upon rotational manipulations and to remove the shaved debris and contents.
[0006] Such K-files and reamers are standardized having diameters at a distal end of 0.02 pitch between 0.06 mm and 0.10 mm, 0.05 pitch between 0.10 mm and 0.60 mm, and 0.10 pitch at 0.60 mm or higher but up to 1.40 mm. Accordingly, the materials are formed as square bars having the same cross section as the targeted products.
[0007] The apparatus for twisting ultrafine rectangular bars having such diameters and cross-sectional shapes includes a chuck for holding the ultrafine rectangular bar as a material, and a plurality of vise clamps for restricting the ultrafine rectangular bar in contact with the side surface of the bar. After the ultrafine rectangular bar having the same cross-sectional shape and diameter as the targeted products is held by the chuck, the ultrafine rectangular bar is made in contact with the vise clamps, and then, the bar can be twisted by rotating correlatively the chuck and the vise clamps and isolating the chuck and the vise clamps from each other as restricting the ultrafine rectangular bar with the vise clamps (see, e.g., Japanese Patent Publication Nos. JB-61-53059, JB-62-22733).
[0008] With the above twisting apparatus, however, the positional relation between the corner portion of the ultrafine rectangular bar held by the chuck and the vise clamp is not controlled at all. That is, when the vise clamp is made coming closely to the ultrafine rectangular bar, what portion of the ultrafine rectangular bar comes in contact with the vise clamp is not managed. Therefore, when the twisting work for the ultrafine rectangular bar is started, the twisting starting position may be deviated in the axial direction between starting where the vise clamp contacts with a plane and starting where the vise clamp contacts with a corner portion, so that there arises a problem that the length of the twisting portion become not unified.
SUMMARY OF THE INVENTION
[0009] It is an object of the invention to provide an ultrafine rectangular bar twisting apparatus making stable the twisting start position at each ultrafine rectangular bar and realizing unified lengths of the twisting portion.
[0010] A twisting apparatus for an ultrafine rectangular bar to solve the above problems according to the invention includes: a chuck for holding a proximal end of the ultrafine rectangular bar; chuck driving means for holding or releasing the proximal end of the ultrafine rectangular bar by driving the chuck; at least two vise clamps structured to contact with and isolated from the ultrafine rectangular bar held by the chuck, each of the vise clamps having a pressing surface capable of contacting to a side surface of the ultrafine rectangular bar; vise clamp driving means for driving the vise clamps to move the vise clamps to contact with and isolated from the ultrafine rectangular bar; moving means for correlatively moving the chuck and the vise clamps along the axial center of the ultrafine rectangular bar held by the chuck; and rotating means for correlatively rotating the chuck and the vise clamps around the axial center of the ultrafine rectangular bar held by the chuck, wherein the chuck driving means and the vise clamp driving means are so controlled that, after the proximal end of the ultrafine rectangular bar is held by the chuck where the vise clamps are placed closely to the ultrafine rectangular bar, the chuck disengages ultrafine rectangular bar when the vise clamps contact to the ultrafine rectangular bar and then engages again the ultrafine rectangular bar, in a case where the vise clamps are approached closely to the ultrafine rectangular bar held by the chuck to twist the ultrafine rectangular bar upon isolating, as rotated correlatively, the chuck and the vise clamps from each other.
[0011] With the above twisting apparatus for the ultrafine rectangular bar (hereinafter, simply referred to as “twisting apparatus”), the shape of the holding portion of the chuck is circle, and a corner of the ultrafine rectangular bar can correspond to a corner of the vise clamps when the vise clamps are made come closer and in contact with the ultrafine rectangular bar. That is, in a case where the corner of the ultrafine rectangular bar held by the chuck does not correspond to the corner of the vise clamps, the ultrafine rectangular bar rotates according to the shape of the vise clamps without disengaging from the chuck to render the corners of the vise clamps and the ultrafine rectangular bar face to each other upon disengaging the ultrafine rectangular bar from the chuck when the vise clamps come in contact with the ultrafine rectangular bar.
[0012] Accordingly, after the vise clamps contact to the ultrafine rectangular bar, the chuck is made closed again to hold the ultrafine rectangular bar, thereby rendering the ultrafine rectangular bar face to the vise clamps as facing to each other at the corners. Therefore, where the chuck and the vise clamps are isolated from each other at a prescribed rate as rotated correlatively, the ultrafine rectangular bar can be twisted with a prescribed pitch.
[0013] With the twisting apparatus thus described, it is preferable to provide a stopper contacting to the distal end of the ultrafine rectangular bar at a prescribed position on the axial center of the ultrafine rectangular bar held by the chuck, wherein the moving means, the chuck driving means, and the vise clamp driving means are so controlled that, where the vise clamp approaches closely and contacts to the ultrafine rectangular bar after the chuck holds the proximal end of the ultrafine rectangular bar, the chuck disengages from the ultrafine rectangular bar, and the distal end of the ultrafine rectangular bar is made in contact with the stopper upon moving correlatively the chuck and the stopper.
[0014] In the twisting apparatus, the length of the ultrafine rectangular bar, held by the chuck, from the chuck to the distal end is prescribed, and a corner of the ultrafine rectangular bar can correspond to a corner of the vise clamps. That is, where the chuck disengages from the ultrafine rectangular bar when the vise clamps approach to and come in contact with the ultrafine rectangular bar held by the chuck, and where the distal end of the ultrafine rectangular bar is made in contact with the stopper by correlatively moving the chuck and the stopper with respect to each other, the correlative position of the ultrafine rectangular bar with respect to the chuck is changed, where the chuck and the stopper are moving, according to the movements when the distal end of the ultrafine rectangular bar contacts to the stopper.
[0015] When the distance between the chuck and the stopper reaches a prescribed value, the ultrafine rectangular bar can be corresponded to the shape of the vise clamps, and the prescribed length can be held by stopping movements of the chuck and the stopper and by holding the ultrafine rectangular bar upon closing the chuck. Therefore, the position of starting the twisting process at the ultrafine rectangular bar can be regulated, so that the apparatus can treat good twisting products with unified lengths of the twisted portions.
[0016] With the above twisting apparatus, the vise clamp is preferably disposed at a position such that a portion of a clamp surface for clamping a side surface of the ultrafine rectangular bar can be in contact with a portion of the adjacent vise clamp.
[0017] Respective positions of the clamps can be adjusted along the exterior shape of the ultrafine rectangular bar when the vise clamps approach and come in contact with the ultrafine rectangular bar.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The above and other objects, features and advantages of the present invention will become more apparent from the following description of the presently preferred exemplary embodiments of the invention taken in conjunction with the accompanying drawings, in which:
[0019] [0019]FIG. 1 is a schematic view showing the entire structure of a twisting apparatus according to the invention;
[0020] [0020]FIG. 2( a ), 2 ( b ) are illustrations describing a relation between a holding portion of a chuck and a cross-sectional shape of an ultrafine rectangular bar;
[0021] [0021]FIG. 3 is an illustration showing a structure of a vise clamp;
[0022] [0022]FIG. 4 is a timing chart for illustrating drive timings of essential portions in the twisting apparatus;
[0023] [0023]FIG. 5( a ) through FIG. 5( f ) are process diagrams showing a twisting process sequence for the ultrafine rectangular bar with the twisting apparatus; and
[0024] [0024]FIG. 6( a ), 6 ( b ) are illustrations showing maintenance work of the ultrafine rectangular bar with the vise clamps.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0025] Hereinafter, referring to the drawings, preferred embodiments of the invented twisting apparatus are described. FIG. 1 is a schematic view showing the entire structure of a twisting apparatus according to the invention; FIG. 2( a ), 2 ( b ) are illustrations describing a relation between a holding portion of a chuck and a cross-sectional shape of an ultrafine rectangular bar; FIG. 3 is an illustration showing a structure of a vise clamp; FIG. 4 is a timing chart for illustrating drive timings of essential portions in the twisting apparatus; and FIG. 5( a ) through FIG. 5( f ) are process diagrams showing a twisting process sequence for the ultrafine rectangular bar with the twisting apparatus.
[0026] The twisting apparatus according to the invention is for twisting ultrafine rectangular bars formed in having very fine diameters and cross sections in triangle or square, and is allowing desirable manufacturing of reamers and files used as an endodontic instruments in dental treatments.
[0027] Particularly, the ultrafine rectangular bar is extended along the vise clamp by loosening the chuck's holding of the ultrafine rectangular bar in association with the contact of the vise clamp to the ultrafine rectangular bar where the chuck's holding position of the ultrafine rectangular bar is different from the disposed direction of the vise clamp. With this operation, the holding position of the ultrafine rectangular bar is made corresponding to the vise clamps, and the ultrafine rectangular bars, even where supplied in any orientation, can take the same orientation at a starting time of the twisting process with the vise clamps, where the chuck re-holds the ultrafine rectangular bar, so that the distances between the chuck and twisting starting position can be set equally.
[0028] By providing the vise clamps and the stopper to render the chuck holding the ultrafine rectangular bar correlatively approach to the stopper, by loosening the chuck's holding of the ultrafine rectangular bar when the distal end of the ultrafine rectangular bar contacts to the stopper, and by holding again the ultrafine rectangular bar with the chuck when the distance between the stopper and the chuck coincides to a prescribed amount, the length from the distal end of the ultrafine rectangular bar to the chuck can be maintained at a prescribed amount. Therefore, the portion at which the twisting process is made on the ultrafine rectangular bar can be set as having the same length.
[0029] The twisting apparatus shown in the drawings is constituted of a chuck portion A having a chuck 2 for holding the ultrafine rectangular bar 1 , a vise clamp portion B for rendering a twisting process in contact with the ultrafine rectangular bar 1 , and a stopper portion C. The ultrafine rectangular bar 1 held by the chuck portion A is positioned by the stopper portion C, and as the side surface of the ultrafine rectangular bar 1 is restricted by the vise clamp portion B and rotated, the chuck portion A and the vise clamp portion B are isolated correlatively, thereby allowing the process for twisting the ultrafine rectangular bars 1 having a prescribed length scope.
[0030] As described above, the chuck portion A and the stopper C are mutually come closely and isolated from each other, and the chuck portion A and the vise clamp portion B approach to and isolated from each other as rotated mutually. Accordingly, with the chuck portion A, the vise clamp portion B, and the stopper portion C, any one of those mechanisms is immovable whereas the others are movable. Which mechanism is immovable or movable is not particularly limited, but it is better off that those mechanisms are mutually, organically structured as movable and immovable.
[0031] In this embodiment, therefore, the chuck portion A is rotatable and can approach to and isolate from the vise clamp portion B, as well as the stopper portion C. The vise clamp portion B and the stopper portion C can be formed as entirely different structures, and the position of the stopper portion C is adjustable with respect to the vise clamp portion B upon assembling both on the same frame.
[0032] For what the ultrafine rectangular bar 1 is used is not specifically limited, but in this embodiment, the ultrafine rectangular bar 1 is targeting to be K-files and reamers used for endodontic treatment. These K-files and reamers are formed in having cross sections in an equilateral triangle or square and in respective sizes having diameters at the distal end of 0.02 pitch, 0.05 pitch, and 0.10 pitch between 0.06 mm and 1.40 mm. The ultrafine rectangular bar 1 is formed with a tapered shape having {fraction (2/100)} gradient in a range of length at least 16 mm from the distal end 1 b to the proximal end 1 a.
[0033] The material of the ultrafine rectangular bar 1 is not specifically limited, and carbon steel or stainless steel can desirably be used. Particularly, as in this embodiment, when used for medical purposes, the tool inevitably has a proper flexibility and strength, so that materials such as annealed carbon steel or marten site based stainless steel, or austenite based stainless steel drawn in cooling, etc. can be selectively used.
[0034] The chuck portion A includes the chuck 2 for holding the proximal end of the ultrafine rectangular bar 1 , a chuck drive means 3 for engaging and disengaging the ultrafine rectangular bar 1 by opening and closing the chuck 2 , and a rotary means 4 for rotating the chuck 2 . The chuck portion A is structured to approach to and isolate from the vise clamp portion B and the stopper portion C by a drive means 5 .
[0035] The chuck 2 is formed as a collet chuck having plural nails 2 a, and holding surfaces 2 b as inner surfaces of the nails 2 a are formed to be a circle. The chuck drive means 3 has functions to hold or loosen the proximal end 1 a of the ultrafine rectangular bar 1 upon moving the nails 2 a along an axial center 6 , and can use a linear drive member such as an air cylinder or solenoid.
[0036] Accordingly, even where the cross-sectional shape of the ultrafine rectangular bar 1 is in a triangle or square and where the bar is supplied in any position, the chuck 2 can hold the bar in a stable state. By loosening the chuck 2 , the held ultrafine rectangular bar 1 can be rotated freely and moved in a direction of the axial center 6 .
[0037] The rotary means 4 has a function to rotate the chuck 2 around the axial center 6 as a center at a preset rotation number, and any thing can be used as far as having this function. There are motors (electric motors, air motors, etc.) having a deceleration function as such a rotary means 4 .
[0038] The moving means 5 is for reciprocally moving the chuck portion A along axial center 6 , and any thing can be used as far as having this function. In this embodiment, the means 5 is constituted of a screw bar 5 a disposed along the axial center, a motor 5 b for driving the screw bar 5 a, a nut member 5 c secured to the chuck portion A in mesh with the screw bar 5 a. It is to be noted that it is preferable to guarantee reciprocal movements with high accuracy by attaching the chuck portion A to a linear guide member available commercially.
[0039] The vise clamp portion B is structured at a frame 7 in a plate shape. The vise clamp portion B has a plurality of clamps 8 in a number corresponding to the cross-sectional shape of the ultrafine rectangular bar 1 , and each clamp 8 is secured to a tip portion of an arm 9 and is arranged in a staggered manner as to contact to a side surface of another adjacent vise clamp 8 . The arm 9 is attached pivotally around a pivot center 10 as a center to an arm 11 , and the arm 11 is structured as pivotally movable around a pivot center 12 as a center. An air cylinder 13 serving as a drive means for vise clamp is attached to a free end side of the arm 12 . A spring 14 is attached to the arm 9 , and one vise clamp 8 is structured to be pushed to another adjacent vise clamp 8 by the urging force of the spring 14 . It is to be noted that as shown in FIG. 6, the tip of the vise clamp 8 is a clamping surface 8 a in a plane shape, and the clamp surface 8 a comes in facial contact with a flat surface portion 1 a of the ultrafine rectangular bar 1 when the vise clamp 8 approaches to the side surface of the ultrafine rectangular bar 1 and holds the ultrafine rectangular bar 1 .
[0040] With the vise clamp portion B thus structured, the vise clamps 8 adjacent to each other contact to each other due to the urging force of the spring 14 when the vise clamps 8 are made closer to each other by drive of the air cylinder 13 , and can be brought closely to the axial center 6 of the twisting apparatus surely as rendering the contact portions as a guide. While the twisting processing is made on the ultrafine rectangular bar 1 , the vise clamp can follow the change of the diameter of the ultrafine rectangular bar 1 by continuously supplying compressed air to the air cylinder 13 . Accordingly, the ultrafine rectangular bar 1 can be restricted always with an approximately constant force even where the ultrafine rectangular bar 1 is formed in a tapered shape with a diameter becoming smaller as goes from the proximal end 1 a to the distal end 1 b.
[0041] The stopper portion C is for limiting a protruding length of the ultrafine rectangular bar 1 from the chuck portion A to the distal end 1 b by contacting to the distal end 1 b of the ultrafine rectangular bar 1 , and any thing can be used as far as having this function.
[0042] The chuck portion A, the vise clamp portion B, and the stopper portion C thus structured are disposed at respective positions on a frame 15 . That is, the vise clamp portion B is disposed immovably at a prescribed position on the frame 15 ; the stopper portion C is arranged in a manner that the attached position is adjustable with respect to the frame 15 with the vise clamp portion B as a reference; the chuck portion A is arranged movably with respect to the frame 1115 .
[0043] Particularly, the stopper portion C has a set position from the vise clamp 8 of the vise clamp portion B in corresponding to the preset length of the twisting portion, and at this position, the vise clamp portion B and the stopper portion C are secured as not to shift the length between the vise clamp portion B and the stopper portion C. The immovable system is not specifically limited, and for example, the apparatus may use a system such that the stopper portion C can be secured to the frame 15 , or that a screw bar, not shown, is attached to a frame 7 structuring the vise clamp portion B and is secured to the stopper C.
[0044] The distance between the vise clamp portion B and the stopper portion C corresponds to the distance between the distal end 1 b of the ultrafine rectangular bar 1 and the twisting start position. The K-files and reamers as the dental treatment instruments are defined, under the ISO standard, to have a length of the twisting portion from the distal end of 16 mm or more, and therefore, in this embodiment, the interval between the vise clamp portion B and the stopper portion C is set 16 mm whereas the vise clamp portion B and the stopper portion C are respectively secured.
[0045] Control for holding and loosening operation of the ultrafine rectangular bar 1 by the chuck 2 at the chuck portion A, rotary control, moving control of the chuck portion A in a direction along the axial center 6 , and operational control of the air cylinder 13 at the vise clamp portion B can be done with a microcomputer, sequencer, or timing cams.
[0046] In this embodiment, a sequencer is used as the controller, and operation sequence, and operation times, and the like of the respective operational portions are memorized in the sequencer. A sensor 16 is provided at a prescribed position of the frame 15 to detect the reference position of the chuck portion A, and the ultrafine rectangular bar 1 can be twisted by a series of operations with triggering upon a detected signal of the chuck portion A from the sensor 16 .
[0047] Next, the twisting steps of the ultrafine rectangular bar 1 by the twisting apparatus thus structured are described in reference with FIG. 4, FIG. 5, and FIG. 6. It is to be noted that (a) through (f) in FIG. 4, FIG. 5 are shown as mutually related states.
[0048] The ultrafine rectangular bar 1 is supplied in an unmanaged manner to the chuck 2 structuring the chuck portion A, and the chuck 2 is driven by the chuck drive means 3 to render the ultrafine rectangular bar 1 in a held state. As shown in FIG. 4, FIG. 5( a ), the chuck portion A is moved to the reference position detected by the sensor 16 , and a series of operations begins upon the signal from the sensor 16 .
[0049] Where the chuck 2 holds the ultrafine rectangular bar 1 , the motor 5 b structuring the moving means 5 drives, and according to this operation, as shown in FIG. 4, FIG. 5( b ), the chuck portion A moves in a direction of arrow a in FIG. 1. The moving amount of the chuck portion A, or rotational amount of the motor 5 b, is controlled by a timer signal from the sequencer. In a case where, e.g., a pulse motor is used as the motor 5 b, the amount is controlled by the total number of the pulses transmitted to the motor 5 b.
[0050] When the moving amount of the chuck portion A in the direction of arrow a reaches a prescribed length (timer signal, number of pulse signal, sensor, etc. may be arranged), as shown in FIG. 4, FIG. 5( c ), the chuck 2 is so loosened by drive of the chuck driving means 3 as not to drop off the ultrafine rectangular bar 1 . At that time, because the movement of the chuck portion A in the direction of arrow a is continued, the distal end of the ultrafine rectangular bar 1 comes in contact with the stopper portion C according to the continuation of the movement of the chuck portion A in the direction of arrow a and is prevented from further moving.
[0051] When the movement of the chuck portion A in the direction of arrow a ends, the protruding length of the ultrafine rectangular bar 1 held by the chuck 2 protruding from the chuck 2 is set uniformly by the position at which the chuck 2 stops and by the distance to the stopper portion C, so that the protruding length is hardly deviated, and so that stable protruding lengths can be realized.
[0052] In keeping the above state, as shown in FIG. 4 and FIG. 5( d ), the air cylinder 13 is driven to render the vise clamps 8 structuring the vise clamp portion B approach to and come in contact with the ultrafine rectangular bar 1 . FIG. 6 shows this situation. As shown in FIG. 6, the vise clamp 8 approaches to the ultrafine rectangular bar 1 , and when the corner 1 b of the ultrafine rectangular bar 1 contacts to the clamping surface 8 a of the vise clamp 8 , rotational force exerts to the ultrafine rectangular bar 1 according to the contact angle of the corner 1 b of the ultrafine rectangular bar 1 with respect to the clamping surface 8 a. Because the proximal end of the ultrafine rectangular bar 1 is disengaged from the chuck 2 , the ultrafine rectangular bar 1 rotates according to this rotational force. As shown in FIG. 6( b ), when the clamping surface 8 a of the vise clamp 8 comes in facial contact with the flat surface 1 a of the side surface of the ultrafine rectangular bar 1 , the ultrafine rectangular bar 1 stops rotating and keeps the stable position as pushed in a facial fashion from four directions by the vise clamps 8 .
[0053] When a prescribe time passes after the vise clamp portion B begins its operation, as shown in FIG. 4, FIG. 5( e ), the chuck driving means 3 operates to drive the chuck 2 , thereby holding the ultrafine rectangular bar 1 again. The interval between the drive timing of the air cylinder 13 of the vise clamp portion B and the drive timing of the chuck driving means 3 can be a very short time, and from an external viewpoint, closing of the vise clamps 8 according to the drive of the air cylinder 13 is done nearly at the same time as holding of the ultrafine rectangular bar 1 by the chuck 2 .
[0054] As shown in FIG. 4, FIG. 5( f ), then, the motor 4 structuring the rotating means and the motor 5 b structuring the moving means 5 rotate at prescribed rotational numbers, respectively, and therefore, the chuck 2 rotates in a prescribed direction whereas the chuck portion A moves in a direction of arrow b.
[0055] According to rotations of the motors 4 , 5 b as described above, the ultrafine rectangular bar 1 is subject to the twisting processing with a prescribed pitch. The rotation number of the chuck 2 done by the motor 4 and the moving speed of the chuck portion A in the direction of arrow b done by the motor 5 b are synchronized corresponding to the specification of the twisting process. The speed of the twisting process is set according to material and diameter of the ultrafine rectangular bar 1 .
[0056] As described above, by moving the chuck 2 holding the ultrafine rectangular bar 1 in the direction of arrow a, by loosening the chuck 2 when the distal end 1 b approaches to the stopper portion C, by contacting the distal end 1 b of the ultrafine rectangular bar 1 to the stopper portion C where the chuck 2 continuously moves under this state, and by stopping the chuck 2 when the chuck 2 ends the prescribed movement, the protruding length of the ultrafine rectangular bar 1 from the chuck 2 can be regulated.
[0057] The ultrafine rectangular bar 1 can be rotated by the rotation force operating to the ultrafine rectangular bar when the vise clamps 8 contact to the corner of the ultrafine rectangular bar 1 upon approaching and contacting the vise clamps 8 of the vise clamp portion B to the ultrafine rectangular bar 1 in keeping the above state.
[0058] When the ultrafine rectangular bar 1 held by the vise clamps 8 of the vise clamp portion B is clamped again by the chuck 2 , therefore, the protruding length of the ultrafine rectangular bar 1 from the chuck 2 and the held position are always substantially constant, and when the ultrafine rectangular bar 1 is subject to the twisting process after this operation, the position of the twisting start portion and the twisting length are not deviated at all.
[0059] As described above in detail, with the twisting apparatus according to this invention, the ultrafine rectangular bar can be held always with the same position and direction according to the vise clamp's contact to the ultrafine rectangular bar even where the ultrafine rectangular bar supplied from the exterior is held in any position and direction. Therefore, the twisting start positions of the ultrafine rectangular bars become substantially unified, and the products can be manufactured with stable quality.
[0060] By contacting the distal end of the ultrafine rectangular bar held by chuck to the stopper, the protruding length can be set substantially the same amount even where the ultrafine rectangular bar supplied from the exterior is protruded by a certain length or more.
[0061] The vise clamp can be smoothly and surely approached to the ultrafine rectangular bar by contacting a portion of the clamping surface of the vise clamp to the side surface of the adjacent vise clamp.
[0062] The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description, and is not intended to be exhaustive or to limit the invention to the precise form disclosed. The description was selected to best explain the principles of the invention and their practical application to enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention not be limited by the specification, but be defined by the claims set forth below. | The present invention relates to a twisting apparatus for an ultrafine rectangular bar, comprising: a chuck for holding a proximal end of the ultrafine rectangular bar; chuck driving means for holding or releasing the proximal end of the ultrafine rectangular bar by driving the chuck; at least two vise clamps structured to contact with and isolated from the ultrafine rectangular bar held by the chuck, each of the vise clamps having a pressing surface capable of contacting to a side surface of the ultrafine rectangular bar; vise clamp driving means for driving the vise clamps to move the vise clamps to contact with and isolated from the ultrafine rectangular bar; moving means for correlatively moving the chuck and the vise clamps along the axial center of the ultrafine rectangular bar held by the chuck; and rotating means for correlatively rotating the chuck and the vise clamps around the axial center of the ultrafine rectangular bar held by the chuck. The chuck driving means and the vise clamp driving means are so controlled that, after the proximal end of the ultrafine rectangular bar is held by the chuck where the vise clamps are placed closely to the ultrafine rectangular bar, the chuck disengages ultrafine rectangular bar when the vise clamps contact to the ultrafine rectangular bar and then engages again the ultrafine rectangular bar, in a case where the vise clamps are approached closely to the ultrafine rectangular bar held by the chuck to twist the ultrafine rectangular bar upon isolating, as rotated correlatively, the chuck and the vise clamps from each other. | 0 |
BACKGROUND OF THE INVENTION
The invention is in the field of measuring devices, such as for measuring temperature or other parameters. A specific embodiment of the invention relates to a digital thermometer.
Prior art devices of this type typically rely on a temperature responsive element incorporated in a bridge circuit connected to a high precision voltage source. The bridge imbalance due to the temperature responsive arm is converted to a digital number by a suitable analog-to-digital converter. One disadvantage with devices of this type is that their accuracy depends on that of a high precision voltage source, which makes such devices expensive to make and difficult to maintain.
This invention is directed to an improvement in such devices which eliminates the need for a high precision voltage source. In accordance with the invention, dual slope analog-to-digital converter techniques are used in a novel way which provides an accurate measure of temperature or similar parameters without using the previously indispensable high precision voltage source.
In a specific embodiment of the invention, the input capacitor, integrator and detector of the prior art analog-to-digital converter in an autozeroing configuration is combined with a resistance bridge having a temperature responsive arm and a temperature insensitive arm. The bridge is powered by a low precision voltage source. The free side of the input capacitor is connected to the temperature insensitive bridge arm through a first switch, to the temperature responsive bridge arm through a second switch, and to the voltage source through a third switch. The other side of the input capacitor, i.e., the side which is normally connected to the integrator input, is connected to the detector output through a fourth switch in the common autozeroing configuration. By opening and closing the four switches in a sequence which reflects the invented technique, the undesirable effects of long-term changes in the voltage source level and in the offset and drift of the integrator and detector amplifiers are eliminated, and the difference between the two arms of the bridge is measured accurately, thus obtaining an accurate measure of the effect of temperature on the temperature responsive bridge arm.
Specifically, only the second and fourth switches are initially in a closed state, to thereby place on the input capacitor an initial charge which reflects: (a) the voltage level of the voltage source, (b) the resistance of the temperature responsive bridge arm, and (c) the offset and drift of the integrator and detector amplifiers. Then, a dual slope measurement cycle is started comprising a fixed time interval and a variable time interval. During the fixed time interval, only the first switch is maintained in a closed state, all other switches being open, to thereby apply to the integrator a measurement voltage which reflects: (a) the initial charge on the input capacitor, (b) the voltage level of the voltage source, and (c) the resistance of the temperature insensitive bridge arm. During the variable time interval, only the third switch is maintained in a closed state, all other switches being open, to thereby apply to the integrator a reference voltage whose polarity is opposite that of the measurement voltage and whose magnitude reflects the voltage level of the voltage source. The variable time interval ends when the output of the integrator crosses the reference voltage. The duration of this variable time interval is a measure of the difference between the resistances of the two bridge arms, and is therefore a measure of the temperature of interest. If the levels of the voltage source and of the drift and offset of the integrator and detector amplifiers remain reasonably constant during the dual slope measurement cycle, the absolute values of these levels or changes in these levels as between successive measurement cycles have no effect on accuracy. Since each measurement cycle is of the order of milliseconds, it is unlikely that the level of the voltage source or the level of the drift and offset of the amplifiers would change during a measurement cycle. The longer term changes, as between measurement cycles, do not affect accuracy.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic showing of a measuring device incorporating the invention.
FIG. 2 is a timing chart of the voltage signals at certain points in the device shown in FIG. 1.
DETAILED DESCRIPTION
The device shown in FIG. 1 includes an integrator, a detector and an input capacitor which are in the configuration of a prior art dual slope analog-to-digital converter having autozeroing. Specifically, the integrator comprises an integrator amplifier A1, an integrating capacitor C connected between the output of the integrating amplifier and its inverting input, and an integrating resistor R through which the inverting input of the integrator amplifier is grounded. The detector comprises a detector amplifier A2 whose inputs are connected across the integrating capacitor C, with the inverting input of the detector amplifier being connected to the side of the capacitor C which is connected to the output of the integrator amplifier. The right side of an input capacitor C1 is connected to the noninverting input of the integrator amplifier and is connected through a normally closed switch S4 to the output of the detector amplifier A2. The basic operating principles of such converters are discussed, for example, in Hoeschele, D.F., Analog-to-Digital/Digital-to-Analog Conversion Techniques, Whiley, 1968, pp. 381-384, and a converter of this type is the Digital Panel Meter 1230 made by Weston Instruments, Inc.
In accordance with the invention, the left side of the input capacitor C1 is connected to a resistance bridge and a low precision voltage source through suitable switches, and a control network is provided for opening and closing the switches so that long term changes in the voltage source level and in the amplifier drift and offset are eliminated.
The resistance bridge has a temperature responsive arm comprising the series combination of a fixed resistor R1 and a temperature responsive resistor Rt, and a temperature insensitive arm comprising the series combination of fixed resistors R2 and R3. The two bridge arms are connected between a low precision voltage source Ea and ground. The junction between the two resistors of the temperature insensitive arm is connected to the left side of the input capacitor C1 through a normally open switch S1, the junction between the two resistors of the temperature responsive arm is connected to the same left side of the input capacitor C1 through a normally closed switch S2, and the voltage source Ea is connected to the same left side of the input capacitor C1 through a normally open switch S3. The right side of the input capacitor C1 is connected to the output of the detector amplifier A2 through a normally closed switch S4.
In operation, switches S2 and S4 are in a closed state during an initial time interval, with switches S1 and S3 being open during this initial time interval, whereby the input capacitor C1 stores during this initial time interval an initial charge which is the difference between the voltage at the junction of the two resistors forming the temperature responsive bridge arm and the offset and drift of the integrator and detector amplifiers. More precisely, during this initial time interval the left side of the input capacitor C1 is brought to a voltage level equal to the voltage level of the source Ea as reduced by the voltage divider formed by the series combination of the resistors R1 and Tt, while the right side of the input capacitor is brought to a voltage representing the offset and drift of the amplifiers A1 and A2. The initial time interval is followed by a dual slope measurement cycle comprising a fixed time interval followed by a variable time interval.
At the start of the fixed time interval, switches S2 and S4 open and remain open through the end of the variable time interval. Switch S1, which was open during the initial time interval, closes at the start of the fixed time interval and remains closed through the end of the fixed time interval. Switch S3, which was open during the initial time interval, remains open through the end of the fixed time interval. Thus, during the fixed time interval, the integrator amplifier A1 receives a measurement voltage which is the difference between the voltage of the source Ea, as reduced by the voltage divider formed by resistors R2 and R3, and the initial charge on the input capacitor C1.
At the end of the fixed time interval and the start of the variable time interval, switch S1 opens and remains open through the end of the variable time interval, and switch S3 closes and remains closed through the end of the variable time interval. During the variable time interval, the integrator amplifier A1 receives a reference signal whose polarity is opposite that of the measurement signal and whose magnitude is the difference between the voltage level of the source Ea and the initial charge on the input capacitor C1. The variable time interval ends when the output of the integrator amplifier A1 crosses the level of this reference signal. The duration of the measurement cycle is short as compared to the duration of the initial time interval, so that the initial charge on the input capacitor C1 does not appreciable change during a single measurement cycle, but may change as between measurement cycles, to reflect long-term changes in the voltage level of the source Ea and in the level of the offset and drift of the amplifiers A1 and A2.
The control network necessary to open and close the switches at the appropriate times and the digital network necessary to measure the duration of the fixed and of the variable time intervals operates as follows. Prior to a dual slope measurement cycle, switches S2 and S4 are in their normal closed state, whereby the input capacitor C1 stores the initial charge discussed above. A dual slope measurement cycle starts in response to a reset pulse provided either by momentarily closing a suitably powered switch 10 or by suitably time-dividing the powerline frequency by a sync divider 12. The reset pulse, from either the switch 10 or the divider 12 is passed by an OR-gate 14 and is applied to the reset input of a four-stage decimal counter 16 to reset the counter to 9000. The same reset pulse from the OR-gate 14 is applied, through an OR-gate 17 to an AND-gate 18 to enable the gate 18 so that the clock pulses from a clock oscillator 20 are applied to the counter 16. Thus, at the start of the fixed time interval at time T1, the counter 16 starts counting up from the reset count of 9000. At the same time T1, the normally closed switches S2 and S4 are opened by the reset pulse at the output of OR-gate 17, while switch S1 is closed by the logical high signal at the decimal 9 output of the highest order stage in the counter 16. Until time T1 the two inputs of the detector amplifier A2 are at the same level and the output of the detector amplifier A2 is therefore at a logical low state. However, since switches S1, S2 and S4 change state at time T1, the output of the detector amplifier A2 changes at time T1 to a logical high state, thereby maintaining, through OR-gate 17, the open state of switches S2 and S4 even after the reset pulse has ended.
The fixed time interval ends 1000 clock pulses after time T1. At the 1000-th clock pulse from the oscillator 20, the decimal 9 output of the highest order stage in the counter 16 changes from logical high to logical low. This logical low signal returns switch S1 to its normally open state, and the inverse of it, as provided by an inverter 22 is and-ed with the output of OR-gate 17 (which at this time is high) by an AND-gate 24 whose high output closes switch S3. Thus, the variable time interval starts at time T2, and the counter 16 starts counting up from a zero count. The variable time interval ends when the integrating capacitor C discharges at time T3, thereby changing the output of the detector amplifier A2 from a logical high to a logical low. This change closes AND-gate 18, to thereby disconnect the clock oscillator 20 from the input of the counter 16, and the counter 16 stops at a count proportional to the duration of the variable time interval. This count can be displayed at a display 26 which is driven by a suitable driver-decoder network (not shown). The display 26 can be connected to the output of the OR-gate 17 through a suitable controller (not shown) so that the display 26 can be blanked out during the dual slope measurement cycle, so as to prevent flicker and to display only the steady state of the counter 16.
FIG. 2 illustrates the states of the switches and the voltage levels at certain points of the device shown in FIG. 2 prior to and during a dual slope measurement cycle. Assume as an example that the voltage level of the source Ea is 1 volt and the resistances of the two-bridge arms are such that the voltage at the junction between the two resistors of the temperature responsive bridge arm is 0.8 volts and the voltage at the junction between the two resistors of the temperature insensitive bridge arm is 0.5 volts. Assume further that the offset and drift of the amplifiers is 2 millivolts. During the initial time interval, from time T0 to time T1, only switches S2 and S4 are in their closed state, the potential at the left side of the input capacitor C1 is 0.8 volts. The potential at the right side of the input capacitor C1 is 2 millivolts and the charge across the capacitor is the difference between 0.8 volts and 2 millivolts. At time T1, when the fixed time interval starts, switches S2 and S4 change to an open state and switch S1 closes, whereby the potentials at each side of the input capacitor C1 go down by 0.3 volts, which is the difference between the voltage levels of the midpoints of the two-bridge arm. Since a negative measurement voltage is applied to the input of the integrator amplifier A1, the output of the integrator amplifier ramps down. At time T2, when the fixed time interval ends and the variable time interval begins, the input of the integrator amplifier A1 goes up by 0.5 volts, which is the difference between the voltage level of the source Ea and the voltage level at the junction between the two resistors of the temperature insensitive bridge arm. Since a positive reference voltage is now applied to the integrator amplifier A1, the output of the integrator amplifier ramps up until it crosses the level of the reference signal. At that time, the variable time interval ends, switches S2 and S4 close and switch S3 opens. Note that the output of the detector amplifier is at a logical low during the initial time interval, changes to a logical high at the start of the fixed time interval and remains at this logical high until the end of the variable time interval, when it returns to a logical low. The decimal 9 output of the highest order stage in the counter 16 is at a logical high during the fixed time interval, and at a logical low at all other times. The counter 16 receives clock pulses only from the start of the fixed time interval through the end of the variable time interval.
At the end of the variable time interval, the counter 16 has a count which represents only the difference between the resistances of the two bridge arms, provided that the voltage levels of the source Ea and of the offset and drift of the amplifiers A1 and A2 have remained constant during the measurement cycle. Since the measurement cycle is short (e.g. on the order of milliseconds) it is likely that these voltage levels would remain the same within a measurement cycle, although they may have long term changes, as between successive measurement cycles.
The relevant parameters of the resistance bridge may be selected to accommodate a particular situation. For example, the four resistors of the bridge may have the same values at a nominal temperature, whereby the departure from this nominal temperature would be the measured value. The magnitude and polarity of the measurement and reference voltages applied to the integrator amplifier may be different from those described above, and may be selected to accommodate any specific situation. For example, the relevant polarities may be reversed such that the integrator ramps up during the fixed time interval and ramps down during the variable time interval. It should be clear that the switches S1 through S4 should be fast acting switches, such as fast transistor switches, and that a succession of measurement cycles may be carried out by the divider 12 providing reset pulses at a selected interval, e.g. every half second, and that alternately measurement cycles may be initiated by an external control device (not shown) which applies a reset pulse to the OR-gate 14 in response to the occurrence of some external event. | A measuring device such as a digital thermometer uses dual slope analog-to-digital converter techniques but elminates the usual need for a high precision voltage source. An input capacitor is connected through novel switching to the temperature responsive arm and the temperature insensitive arm of a resistance bridge, to the low precision voltage source and to the output of the integrator and detector amplifiers. The switching sequence is such that long term changes in the voltage source and in the amplifier offset and drift are cancelled out during measurement cycles, thereby providing highly accurate measurements without the usual need for an expensive high precision voltage source. | 7 |
[0001] This application claims the benefit of U.S. Provisional Application No. 60/296,666, filed on Jun. 7, 2001.
FIELD OF THE INVENTION
[0002] The field of this invention is packers or plugs which undergo large expansions to set, such as through tubing, followed by setting in casing or open hole.
BACKGROUND OF THE INVENTION
[0003] In through tubing and open hole applications, annular seals are required which have large radial expansion capabilities. For mechanically set elements, the larger the required radial expansion, the more serious the problem of element extrusion under high differential pressure loads. Extrusion would occur beyond the end rings placed there to control that condition. Various designs for backup rings have been tried with only limited success with the exception being where the extrusion gap around such rings is kept to a minimum. This situation usually involved a traditional casing packer application. Prior designs, in large expansion applications have allowed a gap to exist, which has been sufficiently large to allow extrusion to occur.
[0004] Another problem plaguing prior designs of mechanically set packers has been the inability to get a proper set over the length of the element. This happened because element would be pushed from a first end and start to set from that end. If the end near where the setting force was being applied engaged the casing or the open hole, further pushing would not allow the balance of the element to be firmly pressed against the casing or borehole.
[0005] The preferred embodiment of the present invention addresses these shortcomings of the past designs. It has a mechanism for setting from the end opposite of where the pushing force is being applied. Because of this, very long elements can be reliably mechanically set. The sealing element assembly includes a composite structure, which effectively closes the extrusion gap regardless of the large expansion. While the preferred embodiment accomplishes these objectives, the scope of the invention is far broader as will be explained in detail below and illustrated in the claims.
[0006] Of interest with regard to prior designs are U.S. Pat. Nos. 2,132,723; 2.254,060; 2,660,247; 2,699214; 2,738,013; 2,738,014; 2,738,015; 3,392,785; 3,784,214; 4,258,926; 5,775,429; 5,904,354; and 5,941,313. Of more interest among this group of patents is U.S. Pat. No. 5,941,313. It discloses using deformable sheaths surrounding a material placed therein. This structure is taught for service as a main seal or a backup member to the seal but not both. The sheath is a thin walled tubular member formed from a metallic or other material having sufficient strength and elasticity to bend without fracturing. In some embodiments, a resilient material is overlaid on the sheath but no provisions are made to keep this layer from extruding upon set. In another embodiment, exterior deformation surfaces interact with the sheath to redirect its deformation. No explanation is offered as to how pushing on the sheath at a second end results in initial deformation of the sheath against the exterior deformation surface adjacent the first end.
[0007] Testing by applicants has shown that one major concern with pressure set elements is that the element portions closer to where the element is being pushed expand first. This has the potential of weakening the grip of the remaining portions of the element. The present invention overcomes this problem by temporarily stiffening the end being pushed on to allow the remainder of the sealing element to contact the casing or the well bore. Thereafter, with the remote part of the element against a firm support, the proximate portion of the element is forced into sealing contact, overcoming the temporary stiffening. The invention encompasses a variety of ways to accomplish this objective and to prevent or minimize extrusion after the set.
SUMMARY OF THE INVENTION
[0008] A packing element, which is a composite structure, is disclosed. Components contain the sealing portion to minimize extrusion. The element is retained in tension when running in to minimize damage. In the preferred embodiment, a collapsing sleeve transfers setting force applied at one end, to the opposite end to avoid the problem of bunching up the element adjacent to where it is being compressed which could, if not addressed, result in insufficiently low sealing contact pressure in regions remote from where the pushing force is applied.
DETAILED DESCRIPTION OF THE DRAWINGS
[0009] [0009]FIG. 1 is an outer view, partly in section, showing the innermost components adjacent to the mandrel;
[0010] [0010]FIG. 2 is the view of FIG. 1 showing the internal sealing element:
[0011] [0011]FIG. 3 is the view of FIG. 2 showing the layers above the internal sealing element:
[0012] [0012]FIG. 4 is the view of FIG. 3 showing the outer sealing element that makes contact with the casing, tubular or borehole.
[0013] [0013]FIG. 5 is a run in view of the assembly in part section;
[0014] [0014]FIG. 6 is the view of FIG. 5 in the set position;
[0015] [0015]FIG. 7 is a section view along lines 7 - 7 of FIG. 5;
[0016] [0016]FIG. 8 is a section view along lines 8 - 8 of FIG. 5;
[0017] [0017]FIG. 9 is a section view along lines 9 - 9 of FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0018] Referring to FIGS. 1 and 2 the mandrel 10 has a top thread 12 and a bottom thread 14 to allow running into a well. It further comprises a stationary sleeve 16 and a movable sleeve 18 . Sleeve 18 may be actuated in an up-hole direction by known techniques such as use of wellbore hydrostatic pressure against an atmospheric chamber or applied mechanical or hydraulic pressure or combinations of the above. On top of the mandrel 10 are a pair of collapsing sleeves 20 which preferably have openings 22 to selectively weaken them. In between the sleeves 20 is a spacer 24 , which preferably distributes what would be essentially a line contact between ends of sleeves 20 if they were stacked end to end. The spacer 24 can have opposing female receptacles to allow ends of adjacent sleeves 20 to be inserted so they can be guided and held in alignment as a force is applied to movable sleeve 18 . The reasons for using sleeves 20 can be better understood by examining FIGS. 1 and 2 together. As shown in FIG. 2, the internal sealing element 26 spans over sleeves 20 and spacer 24 as it extends between stationary sleeve 16 and movable sleeve 18 . It also covers a seal ring 28 , which has an internal o-ring 30 for the purpose of internal sealing along the mandrel 10 . The problem addressed by sleeves 20 is that when movable sleeve 18 is set in up-hole motion, the element 26 , in the absence of sleeves 20 will tend to bunch up and contact the casing or wellbore at end 32 rather than uniformly along its length or more preferably from the up-hole end 34 . Expansion initially at end 32 is not desirable because it can prevent sufficient contact pressure from reaching the up-hole end 34 for a proper seal.
[0019] The present invention seeks to direct the pushing force from movable sleeve 18 through a mechanism other than the seal 26 for a predetermined portion of its length. Sleeves 20 have sufficient structural rigidity to redirect the pushing force from movable sleeve 18 to the up-hole segment 34 of the sealing element 26 such that the up-hole segment expands first into contact with the casing, tubular or wellbore. After sufficient contact pressure develops, further pushing by movable sleeve 18 collapses one or both sleeves 20 to allow the pushing force from movable sleeve 18 to go into the lower end 32 of the seal 26 and push it out into sealing contact in the manner just accomplished for up-hole segment 34 . The openings 22 are designed to allow sleeves 20 to buckle after up-hole segment 34 is in sealing contact, at which point, in the preferred embodiment they serve no further significant structural purpose. Sealing force on the lower segment 32 of the seal 26 is principally determined by the pushing force into the resilient lower segment 32 after the upper segment has set. Those skilled in the art can appreciate that one or more sleeves can be uses and that each sleeve can be in round or other cross-sectional shape. The column strength of multiple sleeves or even of a single sleeve 20 can vary along its length, by a variety of techniques. The opening, pattern, number, or size can be varied and/or the wall thickness can change along the length. Different materials can be used along the length. The objective of the various combinations described is to have sufficient aggregate column strength to transfer initial expansion by compression of seal 26 to its upper segment 34 first, through the sleeve or sleeves 20 . It is then preferred that after buckling. The sleeves 20 play a minimal part in the compression of the remainder of seal 26 , while recognizing that the mere presence of the collapsed sleeve 20 in the lower end 32 will, by its mere presence distribute some pushing force from movable sleeve 18 to lower end 32 . It should also be noted that sleeve or sleeves 20 could be complete cylinders, with or without a seam or sheet turned into a cylindrical shape or other shape by scrolling. Sleeves 20 can have longitudinal corrugations as another technique for adjusting their column strength. Instead of sleeves, other structures that have column strength to a point and then will buckle can be used to get the desired movement of seal 26 as described above. Some examples are stacked beveled washers, springs, rods and similar elongated structures that ultimately collapse, bend or deform under load. Also envisioned are materials whose properties can change in response to various fields or currents applied to them. Also envisioned is a variability on the hardness of seal 26 acting in conjunction with sleeves 20 to allow for segment 34 being less resistant to expansion so it will make sealing contact first and the balance getting progressively or suddenly stiffer or harder to promote the desired direction of expansion from up-hole segment 34 to downhole segment 32 of seal 26 .
[0020] Apart from the problem of not getting enough contact pressure for a good seal, there is another potential problem that is addressed by the present invention. That problem is element extrusion through end gaps after setting. The solution of the preferred embodiment is shown in FIGS. 3 and 4. FIG. 3 illustrates the use of tubes 36 and 38 , which extend respectively from sleeves 16 and 18 and can be seen in the section view at the top of FIG. 3. Tubes 36 and 38 preferably do not cover the length of seal 26 leaving a gap 40 in between. The preferred material is a continuous-aramid, Kevlar or carbon fiber, tube that is mechanically secured at sleeves 16 and 18 . Tubes 36 and 38 are preferably constructed of braided fibers to facilitate radial expansion of not only seal 26 but also of outer seal 42 (FIG. 4), which is mounted in a recess 44 (FIG. 2) of seal 26 . In the preferred embodiment, the recess 44 is centrally mounted but offset locations can also be used. The recess 44 is optional but its use facilitates the resistance to extrusion after set, as will be explained below. The seal 26 can preferably be a solid rubber mass or segments or a particle material. A particle material offers an added advantage of being able to move freely during the setting operation and a greater ability to conform to irregularities in the shape of the wellbore. The use of tubes 36 and 38 further makes particle materials such as rubber useful because the rubber is elastic and can store energy, which is contained by tubes 36 and 38 . These strong tubes are a significant element in keeping the seal 26 from extruding past sleeves 16 or 18 . Tubes 36 and 38 can be used alone or can be reinforced with overlaying tube segments 37 (see FIG. 7), secured to sleeves 16 and 18 . Such reinforcing tubes can be of the same material or fiberglass matte or woven metal mesh. They would provide additional resistance to extrusion in an area where the mechanical stresses are the greatest.
[0021] Another feature is the use of a tube 46 , which extends from sleeve 16 to sleeve 18 and is securely attached to both. It is preferably a reinforced steel mesh sleeve which provides support for the element 42 when set because it expands into contact with the casing, tubular or wellbore above and below element 42 , thus acting as an extrusion barrier for it. The actual main sealing occurs along the length of element 42 in contact with the wellbore, tubular, or casing. During run in, tube 46 keeps seal 26 in tension to reduce its profile and protects it from abrasion as it is run into the well. Additionally, as the depth increases the additional hydrostatic force applied to an unbalanced piston area in a hydrostatic setting mechanism, helps to keep the seal 26 taut. The use of a recess 44 to mount the seal 42 insures that portions of the tube 46 expand into contact with the wellbore, casing or tubular both above and below seal 42 and preferably in contact with it on both ends to prevent extrusion and, to a lesser extent, apply an additional sealing force.
[0022] Optionally, a barrier material 48 having some lubricity can be applied over tube 46 but under seal 42 . The preferred material is PTFE and its presence keeps the seal 42 from bonding to seal 26 through tube 46 . Other materials such as a mold release can also be used. The objective is to keep adjacent seal components from bonding to each other. If the material further promotes sliding, due to its lubricating qualities, then its performance is even better. As previously stated, tubes 36 and 38 leave a gap 40 in between and the barrier material, preferably in the form of tape can span that gap 40 , thus keeping rubber from seal 42 from bonding to seal 26 at gap 40 . The presence of the barrier material 48 allows seal 46 to move into uniform contact with the surrounding environment without kinking or binding.
[0023] Those skilled in the art will appreciate that the packing element described above insures proper expansion of the underlying or fill material of seal 26 beginning at the end furthest from where the expansion force is being applied. This is accomplished by channeling the applied force to the remote end by a force transfer mechanism such as sleeves 20 . The force transfer mechanism, by design, is overcome after the upper segment 34 is firmly against a surrounding surface to allow the balance of the seal 26 at its lower segment 32 to complete the expansion. While that is going on tubes 36 and 38 and any backup tubes guard against extrusion. The outer seal 42 can expand against the surrounding surface and be surrounded above and below by portions of the mesh tube 46 . For additional protection against extrusion, the ends of the sleeves 16 and 18 can have longitudinal splits giving the effect of long fingers. These fingers 50 are spread against the surrounding space to give an added extrusion barrier. They can be held together initially for run in so as to keep them out of the way. Additionally, tube 46 keeps the run in profile low as well as serving as an extrusion barrier to both seal 26 and outer seal 42 .
[0024] The above description is representative of the preferred embodiment and the various modifications and alterations that can be made within the scope of the invention are clearly defined below in the appended claims: | A packing element, which is a composite structure, is disclosed. Components contain the sealing portion to minimize extrusion. The element is retained in tension when running in to minimize damage. In the preferred embodiment, a collapsing sleeve transfers setting force applied at one end, to the opposite end to avoid the problem of bunching up the element adjacent to where it is being compressed which could, if not addressed, result in insufficiently low sealing contact pressure in regions remote from where the pushing force is applied. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
Reference should also be made to a copending application for "METHOD AND APPARATUS FOR MONITORING TEMPERATURES DURING CATALYTIC REGENERATION FROM A CONTINUOUSLY MOVING INFRARED SCANNING AND DETECTION UNIT FIXEDLY MOUNTED ABOARD AN AIRCRAFT," filed concurrently with the present application on Mar. 15, 1973, Ser. No. 341,649, in the name of Armand C. Comfort, assigned to the assignee of the present application.
FIELD OF THE INVENTION
This invention relates to a method and apparatus for improving the efficiency of catalyst regeneration associated with the refining of hydrocarbons such as occur in catalyst-aided hydrocracking and catalyst-aided reforming processes. More particularly, this invention relates to an infrared scanning method and apparatus for improving catalytic regeneration in such refining operations through careful monitoring of temperatures within vessels associated with the regeneration process.
SUMMARY OF THE INVENTION
In accordance with method aspects of the present invention, accurate indication of regeneration temperatures of catalysts--in real time--instantaneously occurs by monitoring the infrared energy, say in a frequency range greater than 300 × 10 9 , but not more than 10 15 Hz, emitted from a plurality of distributed metallic studs mounted as by welding to the exterior surface of the sidewall of a vessel undergoing catalytic regeneration. The dynamic temperature variations of such energy rays readily indicate regeneration temperatures of the catalyst interior of the vessel. The studs extend through the insulation of the vessel, but do not penetrate its interior. Where the regeneration process is cyclically occurring, not only is there a marked decrease in the time required for regeneration, but there is also better statistical certainty that full regeneration of the catalyst has occurred. Further, real-time thermograms have been found to have surprising value as histograms for prognosticating optimum regeneration conditions.
In accordance with apparatus aspects of the present invention, real-time thermograms of the regeneration cycle are provided by an infrared scanning and detection unit mounted to the bed of a pickup truck positioned adjacent to the vessel associated with the regeneration process. The scanning and detection unit includes a camera unit for detecting infrared energy emitted from studs welded to the vessel. As infrared radiation is emitted from the studs, the camera unit detects the energy by means of an infrared detector. The detector converts the infrared signal to electrical signals. The latter, after amplification, can be used to control the beam of the cathode-ray tube mounted within a console also carried on the pickup bed. The sweep of the cathode-ray tube is matched to that of the camera, so that the resulting image is readily structured to yield both temperature and locational information related to the regeneration process. A recording camera attached adjacent to the screen of the cathode-ray tube photographs the image of the screen. In this way, important regeneration parameters, viz. temperatures, are recorded for future study. Also, by adjusting the temperature sensitivity of the infrared camera unit, wave-front catalyst temperature differences can be indicated over a rather wide range of operating temperatures, say from 1° to 1,360°F.
Still further in accordance with apparatus aspects of the present invention, one or more infrared scanning units can also be mounted to a vertically extending support rail permanently located adjacent to, but horizontally spaced from, a vessel associated with a continuously occurring regeneration process. A column of studs welded to the vessel defines a vertical plane passing through the rail and scanning unit. The camera unit is mounted on an H-frame support which, in turn, is movably mounted to the rail. A drive unit is electrically connected to a control and detection circuit permanently affixed at the base of the rail, the circuit automatically monitoring and initiating operations through a series of switches and other circuit elements, so as to control rectilinear movement of the scanning unit along the rail as a function of time. As a result, a series of thermograms can be generated from different viewing stations adjacent to the vessel undergoing regeneration.
BACKGROUND OF THE INVENTION
Catalytic processes play a heavy role in refining carbonaceous materials. Likewise, regeneration of the involved catalyst logically occupies a correspondingly large amount of a process engineer's time and efforts. For example, in the conversion of high-boiling, nongasoline hydrocarbons into lower-boiling gasoline components, the catalyst-aided process steps of treating, decomposition, fractionation, gasoline stabilization and absorption polymerization requires, for the most part, cyclic or occasional regeneration of the involved catalysts. See for example, Kirk-Othmer, Encyclopedia of Chemical Technology, 2nd Edition, Vol. 15, "Petroleum (Refinery Processes)," page 15 et seq.
Catalysts are usually classified by function--fixed bed, movable bed, or fluid bed--and by process conditions, three typical process examples being set forth below to better illustrate the nature of atalyst-aided processes in general and regeneration techniques in particular:
1. Early catalytic crackers were usually of the fixed-bed type, but today most catalytic cracking is carried out in moving or fluid beds. Regeneration temperatures and pressures in moving and fluid beds are usually in the ranges of 1,000°-1,210°F. and 8-30 psig, respectively;
2. Modern hydrocrackers employed in hydrocracking (an efficient, low-temperature catalytic method for converting refractory middle-boiling or residue streams to high-octane gasoline or jet fuel, etc.) use fixed-bed processing for the most part. After hydrogen has been mixed with the feed, the mixture is heated and contacted with a catalyst in a separate fixed-bed reactor at specified hydrogen partial pressures. Regeneration pressures and temperatures of the catalysts are usually within the ranges of 400°-800°F. and 10-2000 psig, respectively; and
3. Modern catalytic reformers associated with catalytic reforming (upgrading naphthas into high-grade components for fuel blending or petroleum usage in which molecules are rearranged to give a higher antiknock quality at the expense of yield) also employ fixed beds in the main, i.e., it is estimated that less than 5% of U.S. reforming capacity utilizes fluid- or moving-bed processes. Temperatures and pressures for regeneration of catalysts involved in reforming are in the ranges of 800°-1500°F. and 200-400 psig, respectively.
In controlling regeneration temperature and pressure conditions within the above processes, it has been found that the aforementioned variables are usually not monitorable in a direct fashion. Safe engineering practices dictate against the use of internal sensors, for the most part, because associated control and energization elements must in some manner penetrate the sidewalls of the vessels undergoing regeneration. Instead, temperatures and pressures of associated regeneration fluids flowing relative to the vessel are monitored, and temperatures of the catalytic regeneration process are inferred from temperature and pressure values measured at external sensing locations.
Although infrared scanning techniques have been used in many refinery applications, such applications of which I am aware have been limited in scope and function. Moreover, such techniques were thought not to have the capability of monitoring regeneration processes to which the present invention is directed to the extent of detecting and differentiating adjacent temperature stations within catalyst beds of vessels undergoing regeneration, since such vessels are for the most part heavily clad with insulation, so that metallic sidewalls (which could be associated with interim regeneration temperature characteristics) are almost totally hidden from camera view.
OBJECT OF THE INVENTION
An object of the present invention is the provision of a novel method and apparatus for improving efficiency of regeneration of catalysts employed in catalytic processes in general and catalytic hydrocracking and reforming processes in particular, through the careful infrared monitoring of temperatures associated with catalytic regeneration within reactors or within separate regeneration facilities of vessels associated with the regeneration process.
Further objects and features of the present invention will become more apparent to those skilled in the art in the following detailed description of preferred embodiments, wherein:
FIG. 1 is a perspective view of a vessel undergoing catalytic regeneration, such vessel being monitored by means of an infrared scanning and detection unit mounted on a pickup truck bed, such unit detecting infrared energy emitted from a plurality of metallic studs mounted to the sidewall of the vessel extending through the insulation thereof;
FIGS. 1A and 1B are detailed drawings of alternate metallic stud patterns positioned on the side wall of the vessel of FIG. 1;
FIG. 2 is a schematic diagram of the infrared scanning and detection unit of FIG. 1;
FIG. 3 is a thermogram produced by the infrared scanning and detection unit of FIG. 2, in which temperatures associated with the plurality of studs in FIG. 1 are indicated;
FIG. 4 is a side elevation of another vessel undergoing catalytic regeneration in which fixed-catalyst-bed temperatures are automatically monitored by means of a cyclically repeating infrared scanning and detection unit, such unit including a vertical traveling infrared camera unit, movable along an upright support rail extending parallel to the vessel to be monitored;
FIG. 5 is a schematic diagram of the scanning and detection unit of FIG. 4;
FIG. 6 is a side elevation, slightly enlarged of the scanning unit of FIG. 4;
FIG. 7 is a sectional view of the scanning unit of FIG. , taken along line 7--7 of FIG. 6;
FIGS. 8 and 9 are sections taken along 8--8 and 9--9, respectively, of FIG. 6; and
FIG. 10 is yet another section, taken along line 10--10 of FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, temperatures interior of vessel 10 undergoing catalytic regeneration are quickly and easily indicated by infrared scanning and detection unit 11. Vessel 10 is associated with the refining of hydrocarbons in general, and in hydrocracking and reforming processes in particular. Since the temperatures interior of vessel 10 are indicative of the catalytic regeneration process and such temperatures dynamically vary the function of catalyst position within the vessel, scanning and detection unit 11 must be able to dynamically detect slight temperature variations from position to position along the vertical extent of vessel 10.
In accordance with the present invention, scanning and detection unit 11 provides the required temperature resolution in the vertical plane of vessel 10, and includes control console 12. Console 12 comprises cathode-ray tube display unit 13 and recording camera 14. Briefly, in operation, images at cathode-ray tube display unit 13 are produced at a stationary viewing station by infrared camera 16 mounted on pedestal 17, journaled in turn at bed 18 of truck 19 in position adjacent to console 12. The vertical extent of camera image, and hence to available vessel scanning region, is variable by movement of truck 19 so as to allow infrared camera 16 to scan the entire vessel, say when vessel 10 is used as a separate regeneration facility in a fluid-bed or moving-bed regeneration process, or scan only a section of vessel 10, say when the vessel is associated with a fixed-bed process.
The temperatures interior of the vessel are indicated by series of studs 20. The shape of studs 20 can vary, but are preferably of a circular cross-section for ease of manufacture. In accordance with the present invention, studs 20 are mounted as by welding to the exterior of sidewall 21 of vessel 10, and protrude through insulation 22 so that ends 20a are visible to the naked eyes of the human operators of scanning and detection unit 11.
Orientation of studs 20 varies in a preselected manner --say along a vertical, discontinuous column coextensive with insulation 22, having one "edge" thereof defined by a straight vertical line intersecting unattached ends 20a of studs 20, but terminating at ends coincident with base stud 20b and overhead stud 20c. Thus, it is apparent that the studs themselves define a series of exterior, equidistant locations coincident with a common vertical plane passing through both stud ends 20a and axis of symmetry A--A of vessel 10.
Associated with the aforementioned series of exterior locations is a set of imaginary, equidistant temperature stations interior of vessel 10, not shown. Such set of imaginary stations also lies in the aforementioned vertical plane and intersects that plane along a vertical line that is tangent to the interior surface of sidewall 21. The interior stations of each set are also laterally offset from corresponding exterior locations by a distance equal to at least the thickness of sidewall 21 and the thickness of insulation 22. In addition, if the length of each stud is above the exterior surface of insulation 22, such incremental length must also be added to obtain the aforementioned lateral offset distance. But if the stud height is coincidental with the outer surface of insulation 22, it is apparent that the previously mentioned plane of reference will intersect stud ends 20a along a vertical line that also would be tangent to the outer surface of insulation 22.
Study patterns other than the aforementioned discontinuous column arrangement of FIG. 1 could also be used. For example, studs 20 can be oriented in a series of vertically extending, cyclically repeating 5-spot patterns. See FIG. 1A. Each 5-spot pattern would be positioned on an imaginary curve section, such sections intersecting outer end surfaces 20a of studs 20 and having an axis of formation coincident with the axis of symmetry A--A of vessel 10. As a still further modification of the stud pattern of FIG. 1, it is also contemplated that studs 20 could be oriented in a series of sinusoidal patterns having as a principal reference axis a vertical line tangent with the outer surface of insulation 22 of vessel 10. See FIG. 1B. Note that in the aforementioned sinusoidal pattern, remote ends 20a of the studs would be positioned in imaginary curve section having an axis of formation also oincident with the axis of symmetry A--A of vessel 10.
It should be apparent that in all of the examles of possible stud patterns described above, studs 20 do not extend interior of sidewall 21 of vessel 10. However, because of the solid heat transfer characteristics of the metal of the studs, there is still sufficient proximity of location adjacent to temperature stations interior of the vessel during regeneration that catalyst temperature can be clearly indicated by the surface temperatures of remote ends 20a of each stud 20. Moreover, since the temperatures can be most easily detected if remote ends 20a of the studs are visible to the human eye, as previously mentioned, the length of each stud is accordingly preferably at least equal to the thickness of insulation 22.
While the spacing and number of studs 20 are dependent upon stud pattern, as described above, other factors of interest should be mentioned, including bed length and heat transfer characteristics of sidewall 21 and studs 20. As a minimum, the stud number per unit length of vessel must be sufficient to insure full top-to-bottom temperature information of each catalyst bed during each regeneration cycle. I.e., the vertical extent of the image of infrared camera unit 16, say as indicated by phantom lines 23, must be sufficient to indicate full top-to-bottom regeneration temperature variations as a function of time.
The process of mounting studs 20 to vessel 10 is straightforward: after each stud has been correctly positioned in any of the aforementioned patterns, welding of the studs is carried out using conventional welding techniques. Vessel 10 can then be stress-relieved.
FIG. 2 illustrates operation of scanning and detection unit 11 of the present invention in more detail.
As indicated, infrared camera unit 16 includes focusing spherical mirror 25. Mirror 25 is seen to be centrally disposed within housing 26. Infrared radiation enters through optic window 27 and is focused by mirror 25. The camera scans the total viewable space in two ways: vertically with oscillating mirror 28, and horizontally with multisided prism 29. The resulting scan radiation then propagates through lens system 30 to infrared detector 31. Infrared detector 31 converts the radiation signals to electrical video signals using a photovoltaic effect, as provided by, say, an indium antimonide photovoltaic detector. Liquid nitrogen housed within cooling system 33 provides required cooling of detector 31.
After amplification by amplifier 32, the signals from detector 31 enter console 12 and are again amplified, say by amplifier 34. The amplified signal is then used as a modulating signal for cathode-ray tube display unit 13. Cathode-ray tube display unit 13 is seen to have cathode-ray-tube screen 36. The intensity of the image provided at screen 36 is, of course, a function of the variation in modulating signal provided by amplifier 34. The resulting flickering image (intensity modulation) is photographed by recording camera 14 (see FIG. 1) in time and geometric synchronism with the raster sweep of camera unit 16 over the viewable space of interest. Control circuit 38 connected between cathode-ray tube display unit 13 and infrared camera unit 16 controls the entire infrared scanning and detection operations, as explained in detail below.
The principle of operation of scanning and detection unit 11 is relatively simple. Hot objects, such as studs 20 mounted to vessel 10 of FIG. 1, give off higher frequencies of infrared rays than do other objects. In detecting the rays, say in an infrared frequency range greater than 300 × 10 9 , but not more than 10 15 Hz, primary optics window 27 and spherical mirror 25 form an image of the object at prism 29. With regard to horizontal resolution of the object, assume prism 29 is an 8-sided prism, and is rotating at about 200 revolutions per second. Accordingly, it follows that 1600 horizontal lines of identifying information could be scanned each second of operation of camera unit 16. Likewise, if each scan frame on screen 36 contains 100 vertical lines, then 16 frames of information are produced each second of camera operation. With regard to temperature resolution, such values are usually determined by comparing the object's infrared radiation to that of its surrounding background radiation or to that of a reference source, as expressed in the following equation:
P = εσT.sup.4 /π (1)
wherein:
T is the absolute temperature in degrees Kelvin;
ε is the emissivity of the surface of the plane; and
σ is the Stefan Boltzmann constant of 5.6697 × 10 - 8 watts/M 2 °K - 4 .
The video signal derived from a scene based on the difference in power being radiated from different areas of the scene may be expressed by taking the partial derivative of equation (1) above with respect to temperature, T, and emissivity, ε. ##EQU1## Emissivity of the object may be considered to be a constant equal to unity, with equation (2) becoming: ##EQU2## with
ΔT = (T.sub.2 - T.sub.1)
in which the power change (ΔP) from one object has an emissivity of unity (ε = 1) and a temperature T 1 , as compared to that of a second object with an emissivity of 1 (ε = 1) and a temperature of T 2 .
Of course, the ratio of horizontal and vertical scanning frequencies of the final image of the objects can be altered, if desired. I.e., the line raster can move slowly in a vertical direction, if need be. Thus, the photograph of screen 36, taken with an exposure time of 0.5 seconds or longer, will have superimposed upon itself several frames of the same viewable space, so that line pattern of the moving images on the screen is not noticeable. The resulting multiframe photograph is referred to as a histogram. It should be apparent that the number of superimposed frames per histogram can be varied. By increasing the number, for example, a degree of noise immunity may also be achieved. In this regard, it should be noted that sophistocated statistical techniques may also be used in determining the threshold number. Furthermore, techniques related to the classical problem of image enhancement and image detection are, of course, also available for inclusion with the apparatus of the present invention. Of particular interest in this regard are techniques using the ditigal computer, many of which are detailed in the book "Computer Techniques in Image Processing," Harry C. Andrews, Academic Press (1970).
Timing synchronization between control circuit 38, cathode-ray tube display unit 13 and camera unit 16 can be critical. Not only must control circuit 38 provide for control of the contrast and brightness of cathode-ray tube display unit 13 (contrast being variable as a function of temperature range; brightness being variable as a function of temperature level), but it also must coordinate the sweep of camera unit 16 to that of the display unit. In this regard, as indicated in FIG. 2, drive means 41 is mechanically attached to both mirror 28 and prism 29. Note also that synchronization sweep signals are generated by the interaction of driver means 41 with photocell circuits 42 and 43 and pass through circuit 38 to control operation of cathode-ray tube display unit 13.
Within each field of view of camera 16, the intensity of images (detected frequency) can also be compared, visually, with thermograms of objects of known temperatures, so as to predict the temperature of the images at screen 36. However, with regard to the use of camera 16 to measure the temperatures interior of vessel 10 of FIG. 1, it should be recalled that the heat transfer characteristics of each catalyst bed of the vessel vary rapidly with time and location. Hence, the frequencies of scan of camera 16 must be high enough to provide for such indications as a function of time throughout each regeneration cycle. In this regard, it has been found that thermograms 40 can be generated rapidly enough to provide the required information to optimize the regeneration process, if camera 16 is provided with the aforementioned horizontal and vertical scanning characteristics.
FIG. 3 illustrates a typical thermogram 40 in more detail. As indicated, the temperature differences between the images of the studs attached to the vessel undergoing regeneration appear--in real time--as a black-and-white image. These images appear as flickering lines upon screen 36 of cathode-ray tube display unit 13 of FIG. 2 in time and geometric synchronism with the sweep of camera unit 16. In that way, the resulting images effectively depict the studs in this true geographic perspective with respect to the scanning station. Sensitivity of each resulting thermogram 40 is indicated by scales 44 and 45 placed to the left and right sides of the thermogram as viewed in FIG. 3 (gradation: 1-1000). A gray scale is presented at the bottom of the thermogram at 46 and represents a scale in which a shade of grey equals √2 times the intensity of the next preceding level. Not only are visual methods available to determine temperature levels of each thermogram 40, but also automatic machine comparison techniques can be used to analyze the informational content of each thermogram 40. For example, a digital comparison circuit (not shown), say located internally of control circuit 38, could be used to automatically analyze a series of thermograms without need for human intervention, such circuit using a binary scale (ONE and ZERO) in which the ONE state is a black dot and the ZERO state is a white dot after analog-to-digital conversion of the signals from detector 31 has occurred. Each ONE or ZERO state can be determined over a selected range of temperatures. Shades between the ZERO and ONE states reflect gradations of temperature levels within the selected range. Also, the resulting thermograms can be compared--line by line--with previously obtained thermograms which represent instances in the regeneration cycle in which exceptional response levels occur. In that way, optimization of the currently occurring regeneration process can be obtained.
Modification
FIG. 4 illustrates a modification of scanning and detection unit 11 of FIG. 1 for viewing vessel 10 from a series of cyclically repeating view stations, i.e., say from view stations A and B of FIG. 4.
As shown, reference numeral 50 indicates the modified scanning and detection unit in detail, scanning and detection unit 50 being seen to include camera unit 51 movable along support rail 53 and detection and control circuit 52 fixed in position at the base of rail 53. Rail 53 is parallel but laterally offset from a plurality of metallic studs 54 of vessel 10 and is held at its ends by catwalk 55 and by base plate 56. Movement of the camera unit along rail 53 is provided by a drive unit, generally indicated 57.
In operation, as set point conditions occur, as indicated by control unit 52 as explained hereinafter, camera unit 51--on command--moves in a vertical direction along rail 53. When camera unit 51 is at scan station A or B, however, movement of the camera unit ceases and the camera is activated to detect the emission of infrared energy from studs 54. In that way, temperatures within associated sets of locations within fixed catalyst bed 58 interior of vessel 10 can be determined in the fashion as previously described with reference to FIG. 1. Note that each scanning station is fixed at a selected but different height above base 56. Thus, at each of stations A or B, the focal lengths of camera unit 51 can be accurately controlled so that the total field of view (as defined by phantom lines 59 of camera 51) is equal to at least the vertical extent of each catalyst bed 58. In that way, temperature rises occurring within each catalyst bed 58 can be easily indicated and recorded as a function of time.
FIG. 5 schematically illustrates operation of modified scanning and detection unit 50 in more detail. As schematically illustrated, camera unit 51 and junction box 60 move along rail 53 by operation of driving unit 57. Driving unit 57 includes motor 61. Motor 61 has a shaft connected through pinion gear 62 to rack 63 mounted to rail 53. Windings 68 and 69 of motor 61 are selectively activated to control rectilinear movement of camera unit 16 in the manner described below. Support for camera unit 51 and junction box 60 is also described in detail below.
Motor 61 can be appropriately connected to a source of energy through operation of timing wheel 66 in conjunction with double-elemented control switch 67 forming elements of control unit 52. Briefly, in the ON state, double -elemented switch 67 allows current flow to either winding 68 or 69 of motor 61. Rotation of the shaft of motor 61 is either in a clockwise or a counterclockwise direction, such rotation being converted through pinion gear 62 to rectilinear movement of camera unit 51. Rectilinear movement is either in an upward direction from station A to station B or in a downward direction from station B to station A, depending on which switch element 93a or 93b of switch 67 is connected, as explained below.
Control unit 52 also is seen to include recorder 70 alternatively connected to camera unit 51 through cooperation of a second double-elemented infrared control switch 71. Infrared control switch 71 is placed in cooperative contact with timing wheel 66 at a peripheral location adjacent to that of double-elemented switch 67. Briefly, in operation, timing wheel 66 is seen to be connected to drive motor 72 through gear reducer 73. Cooperative rotation of timing wheel 66 and switches 67 and 71 changes the switching status of the latter so as to provide selected control of drive unit 57 and camera unit 51 as follows:
i. drive unit 57 and camera unit 51 stationary at station A, camera unit 51 is in an ON state;
ii. drive unit 57 and camera unit 51 in rectilinear motion in a first direction traveling from station A to station B, camera unit 51 is an OFF state;
iii. drive unit 57 and camera unit 51 stationary at station B, camera unit 51 is in an ON state;
iv. drive unit 57 and camera unit 51 in reverse rectilinear movement between station B and station A, camera unit 51 is an OFF state.
Operative steps i-iv will now be described in more detail with reference to FIG. 5.
Step (i): Assume switches 64 and 65 have been activated. Timing wheel 66 is in rotation in the direction of arrow C through operation of drive motor 72 and gear reducer 73. Roller 75 of double-elemented infrared switch 71 is placed in rolling contact with node 76 a of timing rack 76 of timing wheel 66. Under such conditions, electrical signals provided by camera unit 51 can be applied, after amplification by amplifier 74 into measuring unit 77 of recording unit 70. Signals from measuring circuit 77 are converted through balancing motor 78 to rotational movement of shaft 78a connected to pen 79 of recording unit 70. Pen 79 moves laterally across chart 80 as a function of signal intensity from camera unit 51. When activated, chart motor 81 is seen to advance chart 80 in direction D. However, chart motor 81 is not initially activated. Only when limit switch 82 is tripped (through interaction of bar 79a of pin 79 and lever arm 84 of mechanical limiter 83) does chart motor 81 become operative. Chart motor 81 continues to operate, once activated.
It should be noted that mechanical limiter 83 is also provided with second lever arm 86. When activated by lever arm 86, contact switch 85 is seen to be tripped, which in turn activates relay 89. Relay 89 includes plunger contact 87, which, when activated, connects horn 88 with source of energy (not shown). It should be apparent that relay 89 allows horn 88 to sound a warning to alert operators within the area that a maximum set point temperature of regeneration has been reached interior of vessel 10. Simultaneously, as relay 89 is operative, there is deactivation of the following: motor 72, connected to timing wheel 66 and chart motor 81. It should also be apparent that when horn 88 is activated, camera unit 51 remains fixed at either station A or B so that the overheated catalytic bed of the vessel can be readily identified.
Step (ii): As infrared controls switch 71 is opened by its roller 75 entering dwell regions 76b of track 76 of timing wheel 66, control switch 67 is activated: roller 90 contacts node 91a of track 91. When this occurs, switch element 93a is placed across contact points 94a. Thus, travel motor 61 becomes energized.
As motor 61 rotates, pinion gear 62 likewise rotates and is caused to travel with respect to rack 63. Since pinion gear 62 and motor 61 are mechancically linked to camera unit 51, the latter is caused to travel from station A to station B.
Since infrared switch 71 is inactive during this time, pen 79 of recording unit 70 falls to a level which places switch 82, controlled by mechanical limiter 83, in an inactive state. Such inactive state in turn deactivates chart motor 81.
Step (iii): With drive unit 57 positioned at station B, camera unit 51 operates in the same manner as previously described with reference to step (i) above. That is, camera unit 51 is operative to provide infrared signals at recording unit 70 through closure of infrared switch 71, i.e., by placement of its roller 75 in rolling contact with node 76c of timing track 76 of timing motor 66.
Step (iv): As infrared control switch 71 is again opened, i.e., opened by its roller 75 entering a second dwell region 76d, roller 90 of control switch 67 enters reversing dwell section 91b on timing track 91. It is apparent that as a result of roller 90 entering reversing dwell section 91b, switch element 93b of switch 67 is placed across contact points 94b. Travel motor 61 becomes energized; however, such energization is in a reverse mode to that previously described, since the direction of current flow relative to windings 68 and 69 is reversed. This causes, in turn, reverse rotation of pinion gear 62 relative to rack 63, which causes travel of camera unit 51 from station B to station A. Camera unit 51 and drive unit 57 return to station A, at which time a second scanning cycle can be initiated, if desired.
FIG. 6, along with detail drawings FIGS. 7, 8, 9 and 10, illustrates the manner in which drive unit 57 and camera unit 51 are supported relative to rail 53.
As indicated in FIGS. 6 and 7, camera unit 51 and drive unit 57 are supported by H-frame support 95, having upright sides 96a and 96b. Upright sides 96a and 96b slideably connect to rail 53 and include a cantilevered section (FIG. 6) which extends away from rail 53 so as to form a support region for camera unit 51. At a more central region of H-frame 95, side 96a is also seen in FIG. 7 to provide support for junction box 60 and travel motor 61. Electrical energy is provided to camera unit 51 and to travel motor 61 through cooperative connection of electrical connector 98 to a source of electrical energy within control circuit 52 at the base of support rail 53 (see FIG. 4). Sides 96a and 96b of H-frame 95 also support, at its interior, a series of balance rollers which provide a balance roller unit, generally indicated at 97 in FIG. 6. The purpose of balance roller unit 97 is to prevent rotation of H-frame support 95 relative to rail 53 about axis C--C (FIG. 6) and axis D-- D (FIG. 8) while still allowing rectilinear movement of H-frame 95 along axis B--B (FIG. 6).
FIG. 8 illustrates balance roller unit 97 in more detail. In this regard, note that the structure of rail 53 is designed to snuggly accommodate roller unit 97 for the previously expressed purpose of preventing rotation about axes C--C and D--D, but allowing rectilinear movement along axis B--B. In more detail, rail 53 is seen to be a conventional I-beam design such that web section 53a is snuggly positioned between rollers 97a-97d of roller unit 97. While rectilinear travel of H-frame support 95 along the rail is permitted, note that rotation about web section 53a is not allowed. Remaining rollers comprising roller unit 97 prevent rotation about the remaining principal rotation axis C--C of FIG. 6 in the following manner: rollers 97e-97h of FIG. 8 prevent movement of H-frame 95 in the direction of end section 53b of rail 53, while similarly positioned rollers of roller unit 97 (two of which being indicated at 97i and 97j of FIG. 6) prevent movement in the opposite direction, i.e., toward section 53c of rail 53.
FIGS. 9 and 10 illustrate the operation of travel motor 61, pinion gear 62 and rack 63 in more detail. As shown in FIG. 9, travel motor 61 includes shaft 61a journaled at sidewall 96b by bearing 98. At a central region of shaft 61a, pinion gear 62 is affixed. Gear teeth are seen to be in mating contact with rack 63 attached to rail 53. Thus, rotation of motor 61 relative to gear 62 is directly converted into rectilinear travel of H-frame 95 in the direction of axis B--B of FIG. 10. Of course the gear ratio of the rack and pinion gear must be designed such that movement along axis B--B is smooth but stable.
Since it is also desirable in some circumstances to remove camera unit 51 from H-frame 95 so as to effect repair, support frame 99 of FIG. 10 is arranged to have aperture 99a open at one end, through which camera unit 51 can be loaded. Snug contact of camera unit 51 and interior of H-frame 99 is provided by having its sidewalls 99b in snug contact with similarly oriented walls of camera unit 51. A lock (not shown) is used to releasably connect camera unit 51 relative to frame 99.
Although certain embodiments of the present invention have been illustrated and described, the invention is not meant to be limited by those embodiments, but by the scope of the following claims. E.g.: (1 ) rather than use internal-combustion-engine-power truck 19 in the embodiment of FIG. 1, a nonpolluting mode of transportation could be substituted, if desired; and (2) rather than using only two viewing stations, as depicted in the embodiment of FIG. 4, a greater number may be employed in some applications. With regard to (2) above, note that in such multistation viewing there must be sufficient reversing time of drive unit 57 to allow camera unit 51 to move from its position at the last-of-cycle scanning station back to its original position at the first-of-cycle scanning station before the cycle is repeated. | Careful and accurate indication of regeneration temperatures of catalysts associated with the refining of hydrocarbons such as occur in catalyst-aided hydrocracking and catalyst-aided reforming processes--in real time--occurs by monitoring the infrared energy, say in a frequency range greater than 300 × 10 9 , but not more than 10 15 Hz, emitted from a plurality of distributed metallic studs mounted as by welding to the exterior surface of the sidewall of a vessel undergoing catalytic regeneration. The dynamic temperature variation of such energy rays readily indicate regeneration temperatures of the catalyst interior of the vessel. The studs extend through the insulation of the vessel, but do not penetrate its interior. Where the regeneration process is cyclically occurring, not only is there a marked decrease in the time required for regeneration, but there is also better statistical certainty that full regeneration of the catalyst has occurred. Further, real-time thermograms have been found to have surprising value as histograms for prognosticating optimum regeneration conditions. | 6 |
The present invention relates to the generation of steam and, more particularly, to a small, compact, quickly responding steam generating device. Small steam generators are utilized in many manually intensive operations such as in a dentist office, dental laboratory or jewelry manufacturer to clean parts, prepare surfaces for casting, molding or coating or to remove wax, polishing compounds, temporary cement, etc.
The small-scale steam generation units presently on the market are complex, expensive; require a large amount of space both on top of and under a bench and consume excessive energy if they are kept on constantly in order to provide quick steam response when intermittently needed during the course of a manufacturing operation.
STATEMENT OF INVENTION
A small, compact, efficient and low cost vapor generating unit is provided in accordance with this invention. The unit provides rapid warmup, instant response, is simple and economical to operate and uses line power and tap water.
The steam generator of the present invention simply comprises a closed, cylindrical metal helix formed from a continuous small diameter tube. The inlet end of the helix contains flow control means and the outlet end contains a nozzle. Heating means such as a cartridge heater is provided for vaporizing liquid within the helix controlled by at least two thermostats provided at the cold and hot ends of the helix. This provides rapid response at startup, prevents burnup at low rates and permits idling of the device with low power demand.
These and many other features and attendant advantages of the invention will become readily apparent as the invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic view of an embodiment of a steam generation unit in accordance with this invention;
FIG. 2 is a view in section taken along line 2--2 of FIG. 1; and
FIG. 3 is an enlarged section taken along line 3 of FIG. 2.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to FIGS. 1-3, the steam generator of the invention includes a heat exchanger 10 in the form of a continuous helix having an inlet end 12 containing an adjustable valve 14, an on-off valve 15 and an outlet end containing a nozzle 16. Each revolution 18 of the helix is in tangential contact with the next revolution 20 and the revolutions are joined by brazing, welding or soldering 22 or other fusion process to provide a structurally rigid, fluid tight, closed cylindrical member having improved thermal conductivity.
A heat source may be provided internally or externally to the surface of the helical tube carrying water to generate steam such as by means of a heat exchange fluid such as liquid metal or by means of combustion gases. A preferred, heating means for a compact table top unit is a cartridge heater 30 having a diameter equal to the internal diameter of the helix 10 and inserted into the helix. The cartridge heater 30 is recessed 3-7 coils from the cold end of the helix. Since the heater is only in point contact with the inner surface 32 of the coils, thermal efficiency is improved by increasing the heat transfer surface by applying a coating 34 of a heat conductive paste to the inner surface 32 of the helix. Thermal efficiency is further improved by applying to the outside surface of the helix a thin coating 35 of a heat resistant, reflective paint such as aluminum automotive manifold paint.
The power and control circuit for the generators comprises an unmodulated power supply 42 suitably line AC (110 V, 1000 watts), connected in series with a switch 40, a cold end thermostat 46, a hot end thermostat 44 and the cartridge heater 30. The thermostats 44, 46 are mounted on metal plates 50, 52 respectively attached to the coils. The thermostats are set in a disable mode and are set at a positive differential of from 10° to 40° F. The cold end thermostat is typically set at a temperature of at least 385° F.
For effective heat transfer, the ratio of the area, A, of the heated surface to the volume, V, of a contained fluid, A/V, should be a maximum. For a cylindrical container (the small diameter tubing) with hot walls, A/V=2/r where r is the radius of the cylindrical container. From this it is evident that the tubing of the helix should be made as small as is practical. In areas having hard water a helix formed of copper tubing having 1/8 inch outside diameter tended to clog. Units having outside diameters of 3/16 inch provided continuous trouble-free operation. The wall thickness of copper tubing in this outside diameter (O.D.) range is typically about 0.030 inch.
An embodiment of a steam generator in accordance with the invention was assembled by forming 3/16 inch O.D. copper tubing into a cylindrical helix having an internal diameter of about 5/8 inch. The helix was brazed continuously to seal the space between the coils. Copper thermostat mounting plates were brazed to the outside surface and the outside surface coated with an aluminum manifold paint. The interior surface was then coated with a water-based curable clay-filled putty thermal bonding material and an electric resistance cartridge heater was inserted into the helix. The thermostats were mounted and connected to a switch. A needle valve and toggle shut-off valve were connected to the inlet end of the helix and an output nozzle to the outlet end thereof. The helix was then mounted in an insulated housing and the water inlet end of the coil connected to line water and the electrical lead connected to line power.
The power switch 40 and on-off water toggle valve 14 are then operated and needle valve 15 adjusted to provide a desired flow rate and quality of steam. The cold end thermostat will demand power and the cartridge heater will heat the coil to 385° F. to provide superheated wet steam having up to 125° F. superheat at a rate up to 4 pounds per hour. The unit operates with nozzle inlet steam pressure about 10 psi below a typical line pressure of about 70 psi. The unit typically operates with a constant mass flow rate. The pressure gradient for steam is approximately 400 times the pressure gradient for water. Flow instability in the coil requires flow rate control at the liquid entrance, hence the needle valve 15.
The hot end thermostat set at approximately 410° F. prevent burn-up at low flow rates. In fact, the needle valve can be set at an idle position at which little or no steam is generated but the unit is ready to generate steam in a very short time interval after increasing the flow rate. By recessing the heater, the cold end thermostat immediately senses the flow of cold water and turns on the heater quickly. If only the hot end thermostat was used, it would take too long for radial thermal gradients to be established and the unit would flood and never recover. If only the cold end thermostat is utilized, the upper end can melt and destroy the unit. The toggle valve permits memory control of a desired flow rate. When the unit is turned off or idling with only power on, a desired flow rate of steam can be achieved by operating only the water toggle valve.
The steam generator unit of this invention is capable of delivering a fully modulated flow of superheated vapor, various degrees of saturated vapor, and heated liquid. The unit idles (zero flow rate) at an elevated temperature, drawing only sufficient energy to make up losses through the unit's insulation. As cool liquid is admitted, its presence must be promptly detected so that the energy source may be activated promptly to reestablish the temperature gradients required to sustain steady state heat transfer to the vaporizing fluid. In the case of an unmodulated energy source (on-off control) this is achieved by mounting a temperature sensor (thermostat) at the inlet end of the helix. Since the unmodulated energy source will provide the same energy input at all flow rates, low flow rates will result in increased temperatures of the output vapor. Since the heat capacity of the vapor is grossly less than the heat capacity of the boiling liquid, the output end of the helix will experience a continuing increase of temperature until destruction occurs. A second temperature sensor (thermostat) mounted at the output end of the helix senses this increased temperature and acts to arrest the energy input. In cases where the energy source is electric resistance heating at a constant power level along the entire length of the helix, the two thermostats need only be connected in series with the resistance heater, and the inlet thermostat be set to actuate at a temperature slightly below the set temperature of the outlet thermostat. This assures that the inlet thermostat is controlling during periods when the unit is idling and has come to a common temperature throughout, and it, the inlet thermostat, will then most quickly sense the presence of cool liquid.
The steam generator unit of the invention is simple, compact and can be reasonably priced. The unit requires only a small amount of bench space, e.g., 5×6 inches, and no under-bench space. Rapid warmup of from cold start to usable steam in less than 5 minutes is possible and then instantly any time thereafter. Once the unit is at temperature, one need just flip the water toggle valve handle on and steam emerges instantly and continously. Operation is economical since electrical energy is only consumed during warmup and while generating steam. The unit uses regular electric outlet 110 V AC and any tap water. As with any device in which water is evaporated, the dissolved minerals remain to ultimately choke shut the water/steam passage. In areas of hard water, the incoming water is passed through a bed of ion exchange resin which substitutes sodium ions for calcium, magnesium, etc., so that the salts that accumulate within the coil tubing are all sodium based salts which are water soluble. A periodic water flush through the coil effectively removes them. The resin, along with a plastic foam filter element, can be contained in a conditioner unit in the water line and the resin quantity is sized to last about six months, at which time the conditioning unit is discarded and replaced. Demineralized water greatly extends the usable life of the coil assembly.
The unit is especially useful in manual manufacturing operations such as jewelry manufacture to remove wax from castings or impressions, to clean jewelry and to remove polishing compounds from intricate networks. Dental offices and laboratories are another and principal market for the unit in which it will be used for removal of polishing compounds from crowns, bridges, dies; cleaning of models, removal of stickly wax from articulations; removal of temporary cement from crowns; removing wax from denture teeth; cleaning of ceramic frames prior to porcelain application; cleaning of porcelain prior to staining and glazing; and cleaning impression trays.
The unit is generally useful for providing superheated vapors from liquids and could be sealed up for generation of mercury vapors, halohydrocarbon vapors (Freons) for uses from nuclear power generation to a steam generator for an automobile.
It is to be realized that only preferred embodiments of the invention have been described and that numerous substitutions, modifications and alterations are permissible without departing from the spirit and scope of the invention as defined in the following claims. | A heat exchanger for an instant steam generator is disclosed comprising a small diameter, continuous metal tube formed into a closed, cylindrical helix. A heat source in contact with either surface of the helix such as a cartridge heater inserted into the helix generates steam in the water flowing in the tube. A set of thermostats in contact with each end of the helix permits fast turn on of the heater but prevents overheating and fusion of the output end of the helix. | 5 |
FIELD OF THE INVENTION
[0001] The present invention relates to a carrier coupled with a stroller to carry goods or support standing of a child.
BACKGROUND OF THE INVENTION
[0002] Children's goods are numerous and often bulky in size. When taking children outdoors, parents have to prepare and carry a lot of goods such as foods, drinks, clothes, toys and sanitary articles. It often happens that one parent has to take care of children while another parent has to carry all the prepared goods in a backpack or bags. This creates heavy burdens to the shoulder and arms of the parents without much chance for rest. It heavily taxes the physical strength and comfort of the parents.
[0003] It also frequently happens that when the parents take a bigger child to shopping malls, they would put the child on the shopping cart to reduce the carrying burden. But the shopping cart is not designed for this purpose, and toppling or colliding of the shopping cart could happen if not maneuvering properly, and could result in hurting the child. Moreover, the shopping cart is commonly made of steel racks which are easily contaminated with all kinds of microbes and bacteria. The child sitting on the cart could be infected by those bacteria when his/her hands touch the mouth and nose after having in contact with the steel racks.
SUMMARY OF THE INVENTION
[0004] In view of the conventional stroller often is foldable to facilitate carrying and storing, and does not provide much room for holding goods, hence parents usually have to carry a backpack or bags to hold the goods when they take children outdoors. In the event that two children are presented or a small child needs constant care, the parents often are overwhelmed. Therefore, it is an object of the present invention to provide a child trailer that can be fastened to the chassis such as a wheel axle, frame or handle of a stroller or hand-moving cart to allow a child to stand thereon or hold goods to alleviate the burden of parents and make moving and taking care of the child easier.
[0005] The child trailer according to the invention includes: a body which has a latch on a rear side with a through hole formed thereon threaded by a strap for storing and also to hook on a handle or other fastening portion of a stroller, and two wheel assemblies at the rear bottom of two sides thereof equipped with shock-absorbing function;
[0006] a joint assembly which is located in front of the body and has a movable joint adjustable to a desired angle before being latched on a fixed condition, hence can be flexibly adjusted according to the height of the transverse chassis such as the wheel axle, frame or handle of the stroller or the body portion to be fastened; and
[0007] a coupler which is fastened to the front side of the joint assembly and includes a seat which has a slide track at each of two sides at the front side thereof, a set of symmetrical first adjustment arm and second adjustment arm slidable on two slide tracks at two sides thereof, and a clamp means located at a lower outer side in front of the first and second adjustment arms.
[0008] The coupler can be adjusted at a desired width. In the event that the width of the transverse chassis such as the wheel axle, frame or handle of the stroller or hand-moving cart for fastening is wider than that of the clamp means at two sides, the first and second adjustment arms can be extended outwards to increase the width of the two clamp means to enhance hitching steadiness. On the other hand, if the width for fastening of the transverse chassis is narrower than that of the interval between the two clamp means, the first and second adjustment arms can be disassembled and exchanged sides left and right to position the two clamp means close to the center and flexibly adjust the distance thereof. In addition, the first and second adjustment arms also can be flipped and installed upside down to dodge the transverse chassis if it is needed to position the two clamp means below the transverse chassis. The first and second adjustment arms also can be disassembled and flipped upside down and exchanged sides left and right to mate the transverse chassis of different strollers or hand-moving carts.
[0009] The invention provides features as follow: the joint assembly is adjustable in angle and the two clamp means is adjustable in width and direction so that the clamp means can be latched with the chassis or other fastenable portion of various types of the strollers or hand-moving carts to fasten the child trailer at the rear side thereof to provide an additional platform for supporting standing of the child or holding goods, thereby can alleviate the burden of the parents when taking the children outdoors.
[0010] In an embodiment of the invention, the child trailer is fastened to the chassis such as the wheel axle, frame or handle of the stroller or hand-moving cart by means of a strap. This embodiment includes a coupler fastened to the front end of the joint assembly and includes a set of fan-shaped and engaged gears hinged on the front end of a coupling duct of the seat. The fan-shaped gears are extendable or retractable synchronously towards or from two sides. Each fan-shaped gear has a telescopic tube assembly at the front end with an adjustable length. The telescopic tube assembly has a latch ring at the front end to latch a strap holder. The strap holder has a strap and an engagement means at the front side that are engageable with each other.
[0011] When the coupler of the invention is in use, fasten the child trailer to the chassis such as the wheel axle, frame or handle of the stroller or hand-moving cart through the strap; through the latch ring at the front end of the telescopic tube assembly, the angle of the strap holder and the stroller or hand-moving cart can be adjusted, and the extended width at two sides and length can be adjusted respectively through the fan-shaped gears and telescopic tube assembly to mate various types of the strollers or hand-moving carts.
[0012] In short, by fastening the coupler to the rear side of any type of the stroller or hand-moving cart, the present invention provides many advantages, notably:
[0013] 1. The joint assembly is adjustable in angle to allow the child trailer to be latched on the chassis of varying strollers or hand-moving carts according to different purposes such as carrying a child or holding goods.
[0014] 2. The coupler is adjustable to a wider range in width to be latched on the chassis of the strollers and hand-moving carts in varying sizes.
[0015] The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a perspective view of the child trailer of the invention.
[0017] FIG. 2 is a schematic view of the invention for clamping a wheel assembly through an elastic element.
[0018] FIG. 3 is a sectional view of a wheel assembly of the invention.
[0019] FIG. 4 is an exploded view of the invention.
[0020] FIG. 5 is a perspective view of the invention in use condition- 1 .
[0021] FIG. 6 is a perspective view of the invention in use condition- 2 .
[0022] FIG. 7 is a perspective view of the invention in use condition- 3 .
[0023] FIG. 8 is a perspective view of the invention in use condition- 4 .
[0024] FIG. 9 is an exploded view of an embodiment of the invention with a strap as a coupler.
[0025] FIG. 10 is a perspective view of an embodiment of the invention with a strap as a coupler.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] Please refer to FIGS. 1 through 4 , the present invention aims to provide a child trailer 1 which comprises a body 2 , a joint assembly 3 and a coupler 4 .
[0027] The body 2 has a holder 21 on a rear side. The holder 21 has an upper side and a lower side formed respectively with a trench 211 and 212 , and a rear side engaged with a latch 22 . The latch 22 has a front side with latch hooks 221 and 222 located respectively on an upper side and lower side corresponding to the trenches 211 and 212 , and a through hole 223 on a lower side at the rear end. The rear bottom of the body 2 has a wheel hub 23 at each of two sides thereof. The wheel hub 23 has an axle hole 231 in the center and a horizontal insertion hole 232 close to the bottom. The insertion hole 232 has a fastening hole 233 corresponding to the axle hole 231 . The fastening hole 233 is hollow and communicates with the axle hole 231 and the insertion hole 232 . The insertion hole 232 holds an elastic element 24 which has two sides indented inwards in the middle to form a set of latch flanges 241 spaced from each other at a distance smaller than the diameter of the axle hole 231 . When the elastic element 24 is held in the fastening hole 233 , the latch flanges 241 are slid and latched in the fastening hole 233 communicating with the axle hole 231 so that the latch flanges 241 are exposed out of the fastening hole 233 . The wheel hub 23 holds axially a wheel assembly 25 . The wheel assembly 25 has a wheel axle 251 at the upper side and an annular groove 252 in the middle portion corresponding to the latch flanges 241 formed at a smaller diameter. When the wheel axle 251 stretches into the axle hole 231 of the wheel hub 23 , the annular groove 252 slides into the latch flanges 241 so that the wheel hub 23 can clamp the wheel assembly 25 . There is a wheel holder 253 located below the wheel axle 251 that is a clip with an opening hinged and openable up and down. The wheel holder 253 has an elastic bracing element 254 close to the opening. The bracing element 254 has two ends butting two corresponding end surfaces of the wheel holder 253 close to the clip opening. There is a wheel 255 axially mounted at a lower side of the wheel holder 253 .
[0028] The joint assembly 3 is located in front of the body 2 , and includes a pair of holding ducts 31 coaxially located at the front end of the body 2 close to two outer sides. Each holding duct 31 has a plurality of splines 311 on the inner rim. There is a coupling duct 32 interposed coaxially between the holding ducts 31 . The coupling duct 32 has inner threads (not shown in the drawings) formed on the inner wall in the center and a plurality of slots 321 formed on the inner wall close to two outer sides corresponding to the splines 311 . The holding ducts 31 and coupling duct 32 are run through by a telescopic sleeve 33 inside. The telescopic sleeve 33 holds a pin 331 corresponding to the axis of the coupling duct 32 . The pin 331 has a smooth portion 3311 close to each distal end at two outer sides. The smooth portion 3311 has two latch means 3312 respectively on an inner and outer end. The pin 331 is coupled with two screws 332 on the smooth portions 3311 close to two distal ends. The screw 332 is slidable on the smooth portion 3311 between the latch means 3312 along the pin 331 to allow the telescopic sleeve 33 to extend or retract. The screw 332 has threads 3321 in the center mating the inner threads of the coupling duct 32 , and is slidably coupled with a tooth duct 333 close to an outer end thereof. The tooth duct 333 has a tooth portion 3331 on the outer wall to latch the splines 311 of the holding ducts 31 and slots 321 of the coupling duct 32 . The tooth duct 333 also has a spring washer 334 close to the center to serve as buffer during screwing.
[0029] The coupler 4 is fastened to the front end of the joint assembly 3 , and includes a seat 41 and a pair of symmetrical first adjustment arm 42 and second adjustment arm 42 a . The seat 41 is fastened to the front end of the coupling duct 32 , and has two slide tracks 411 at two sides of the front side extended outwards from the center, two safety latches 412 close to two outer edges, and a slide rail 413 in the center of the front end. The first and second adjustment arms 42 and 42 a are coupled on the slide rail 413 from two outer sides, and have respectively a penetrating passage 421 and 421 a mating the slide rail 413 . The penetrating passages 421 and 421 a respectively have an opening at each of two sides with a mating latch portion 422 and 422 a located thereon, and an ornamental plate 423 and 423 a latched on the latch portions 422 and 422 a at two outer sides. The penetrating passages 421 and 421 a are coupled on the slide rail 413 from the two outer sides. The first and second adjustment arms 42 and 42 a have respectively a slide flute 424 and 424 a on the rear edge corresponding to and latching on the slide rail 411 so that they can slide on the slide track 411 and slide rail 413 . The first and second adjustment arms 42 and 42 a also have respectively a plurality of notches 425 and 425 a at the upper and lower sides of the slide flutes 424 and 424 a corresponding to the safety latches 412 , hence can be latched and anchored by the safety latches 412 close to the outer edges of the seat 41 . The first and second adjustment arms 42 and 42 a further have respectively a clamp means 426 and 426 a located below an outer side thereof. The clamp means 426 and 426 a include respectively a pair of engaged first clamps 4261 and 4261 a and second clamps 4262 and 4262 a . The first clamps 4261 and 4261 a are located respectively on an outer side of the first and second adjustment arms 42 and 42 a and have respectively an arched surface on the front side indented inwards and have respectively an upper side coupled with an elastic fastener 4263 and 4263 a and have respectively a lower side equipped with a turnable shaft 4264 and 4264 a engaged with the second clamps 4262 and 4262 a . The second clamps 4262 and 4262 a have respectively a rear side formed an arched surface indented inwards, and have respectively a latch portion 4265 and 4265 a formed thereon to latch the fasteners 4263 and 4263 a of the first clamps 4261 and 4261 a.
[0030] Referring to FIGS. 4 and 5 , when the invention is in use, depress the safety latches 412 to extend the first and second adjustment arms 42 and 42 a outwards toward the two outer sides to adjust the clamp means 426 and 426 a at a desired width to mate the transverse chassis of the stroller; then release the safety latches 412 to latch on the corresponding notches 425 and 425 a of the first and second adjustment arms 42 and 42 a to maintain the width of the clamp means 426 and 426 a ; next, unfasten the screws 332 at two sides of the joint assembly 3 , and withdraw the two tooth ducts 333 through the two outer sides with the tooth portion 3331 separated from the slots 321 of the coupling duct 32 ; adjust the holding ducts 31 and the coupling duct 32 to a desired angle, push the two tooth ducts 333 inwards from the two outer sides to latch the tooth portion 3331 on the splines 311 of the holding ducts 31 and slots 321 of the coupling duct 32 , then fasten the screws 332 ; finally, depress the fasteners 4263 and 4263 a to release the second clamps 4262 and 4262 a , so that the transverse chassis of the stroller is located on the indented arched surfaces at the front sides of the first clamps 4261 and 4261 a and the indented arched surfaces at the rear sides of the second clamps 4262 and 4262 a to hitch the clamp means 426 and 426 a on the transverse chassis with the first and second adjustment arms 42 and 42 a positioned above the transverse chassis; then depress and latch the second clamps 4262 and 4262 a on the fasteners 4263 and 4263 a.
[0031] Referring to FIGS. 4 and 6 , in the event that the transverse chassis of the stroller is coupled with a bracing structure, goods holding rack and the like, and the child trailer of the invention cannot be hitched by the clamp means 426 and 426 a of the first and second adjustment arms 42 and 42 a , or the width of the transverse chassis for hitching is shorter than the interval between the clamp means 426 and 426 a , the first and second adjustment arms 42 and 42 a can be disassembled, and the ornamental plates 423 and 423 a also are disassembled from the latch portions 422 and 422 a , exchange the first and second adjustment arms 42 and 42 a left and right so that the clamp means 426 a and 426 are positioned symmetrically on inner sides to couple on the slide rail 413 in a reverse manner; then latch the ornamental plates 423 and 423 a on the penetrating passages 421 a and 421 through latch portions 422 a and 422 , thereby can dodge the structure or fasten on the narrower transverse chassis. Referring to FIGS. 4 and 7 , in the event that the transverse chassis of the stroller has to be latched above the first and second adjustment arms 42 and 42 a , the first and second adjustment arms 42 and 42 a also can be disassembled, exchanged left and right and flipped upside down to couple on the slide rail 413 from two sides thereof so that the clamp means 426 a and 426 are positioned symmetrically on the outer sides; then the clamp means 426 a and 426 can be adjusted to a desired width to be hitched on the transverse chassis of the stroller above the second and first adjustment arms 42 a and 42 . Referring to FIGS. 4 and 8 , in the event that the transverse chassis of the stroller is hitched above the first and second adjustment arms 42 and 42 a , and the transverse chassis also is coupled with a bracing structure, goods holding rack and the like, or the transverse chassis is formed in a narrower width, disassemble the first and second adjustment arms 42 and 42 a , and also the ornamental plates 423 and 423 a at two sides, flip the first and second adjustment arms 42 and 42 a upside down to couple them on the slide rail 413 to position the clamp means 426 a and 426 symmetrically on an inner side; then latch the ornamental plates 423 a and 423 on the outer sides of the two penetrating passages 421 a and 421 , thus the transverse chassis of the stroller can be positioned above the second and first adjustment arms 42 a and 42 with the clamp means 426 a and 426 located on the inner side.
[0032] Referring to FIGS. 3 and 4 , the wheel holder 253 hinged under the body 2 is a clip with an openable opening. The bracing element 254 has two ends butting the end surfaces close to the opening of the wheel holder 253 to provide shock absorbing effect for the wheel holder 253 , hence steadiness and safety improve during moving. Also referring to FIGS. 5 through 8 , the symmetrical first and second adjustment arms 42 and 42 a can be exchanged left and right and flipped upside down to easily couple with various types of strollers or hand-moving carts.
[0033] Refer to FIGS. 9 and 10 for an embodiment of the invention. There is another extensible and retractable coupler 5 fastened to the front end of the joint assembly 3 . The coupler 5 has a strap holder 54 at a front end to fasten the child trailer of the invention to the chassis of a stroller. In this embodiment, the coupler 5 includes an extension means which is a pair of engaged fan-shaped gears 51 hinged on the front end of the coupling duct 32 of the joint assembly 3 . Each fan-shaped gear 51 has a telescopic tube assembly 52 at the front end. The telescopic tube assembly 52 includes an outer tube holder 521 which has a rear end fastened to the fan-shaped gear 51 and a front side coupled with an outer tube 522 . The tubular wall of the outer tube 522 has a plurality of anchor holes 5221 . The outer tube 522 further is coupled with an inner tube 523 at the front side. The inner tube 523 has a rear end coupled with an elastic latch member 5231 which elastically latches on the anchor holes 5221 so that the length of the telescopic tube assembly 52 is adjustable. The telescopic tube assembly 52 has a front end fastened to a latch ring 53 which has a front end hinged a hook 531 at an upper side. The hook 531 has a distal end bent downwards to form a latch portion 5311 . The latch ring 53 further has an elastic latch element 532 at the front end at a lower side corresponding to and latching the latch portion 5311 of the hook 531 . The latch ring 53 latches on a strap holder 54 at the front side. The strap holder 54 has a rear side coupled with a turnable ring 541 run through and latched by the hook 531 of the latch ring 53 . The strap holder 54 further has a strap 542 extended forwards from an inner side of the front end that has constant traces on one surface. The strap holder 54 also has an engaging means 543 on an outer side of the front end with a hole 5431 formed thereon. The engaging means 543 has a safety latch 544 at the rear side butting thereon to prevent loosening thereof.
[0034] When this embodiment is in use, first, extend the hinged fan-shaped gears 51 towards two sides in an isogonal manner, and adjust the length of the telescopic tube assembly 52 so that the coupler 5 is formed in a desired width and length to mate the chassis of a stroller or hand-moving cart; latch the hook 531 of the latch ring 53 on the ring 541 of the strap holder 54 ; adjust the angle between the latch ring 53 and strap holder 54 ; thread the strap 542 through the chassis of the stroller and turn back to thread through the hole 5431 of the engaging means 543 of the same of the strap 542 to be engaged; then latch the safety latch 544 on the engaging means 543 to prevent loosening, thus the child trailer 1 a can be fastened securely on the chassis of the stroller or hand-moving cart. Through the engaged strap 542 and engaging means 543 of the strap holder 54 , the child trailer 1 a can be fastened on the rear side of the stroller. | A child trailer includes a body which includes a plurality of wheel assemblies at the bottom and a joint assembly at the front side to adjust the angle relative to the body. Hence the child trailer can be maintained at a desired angle to support standing of a child or holding of goods. The joint assembly includes a coupler at the front side to fasten the child trailer to the chassis such as a wheel axle, frame or handle of a stroller, thereby can facilitate standing of the child or holding of goods. | 1 |
BACKGROUND OF THE INVENTION
This invention comprises improvements in known types of steel plate lifting clamps and in particular is an improvement over the steel lifting clamps of U.S. Pat. Nos. 3,441,308, 2,852,300 and 3,857,600.
THE PRIOR ART
In U.S. Pat. No. 3,441,308 a steel plate lifting clamp is disclosed in which the cam bears against a plate to be lifted and grips the same between the cam and a facing pad on a facing jaw. The cam is operated by means of a bell crank pivoted at the juncture of the two arms thereof to a radius link and also pivoted at the end of one of its arms to the gripping cam. The other and shorter arm of the bell crank is also pivoted to a special spring mechanism which in turn is pivoted at its other end to an operating lever. The operating lever is pivoted to the clamp body. The aforementioned spring mechanism is quite complicated and incorporates a pair of expander links arranged in juxtaposed and sliding relationship with the upper end of one of said links being pivoted to the short arm of the bell crank and the lower end of the other of said links being pivoted to the operating lever. A spring surrounds the two expander links and operates through shoulders surrounding the links to bring pressure against the links in varying degrees, depending upon the position of the operating lever and the position of the cam as determined by the thickness of the steel plate to be lifted.
Because of this special spring mechanism, the cam may be locked in the clamping position or it may be locked in the open position. The position of the cam in these instances being determined by the position of the operating lever. Additionally, the operating lever may be placed in a neutral or "stabilized" position in which the cam is on but not locked in on position and is, therefore, susceptable to being closed tightly against a plate by operation of the lifting link.
In later commerical embodiments of this clamp, the mechanism was somewhat modified and such clamp is shown in U.S. Pat. No. 3,507,534. Instead of two expander links the spring mechanism of this commerical clamp utilizes a casing pivoted at its upper end to the radius link and an internal rod pivoted at its lower end to the operating lever. A spring within the casing surrounds the rod and bears at its bottom end against the casing bottom and at its upper end against an abutment threaded onto the internal rod. The spring, therefore, tends to urge the outer casing downward into engagement with a cam surface integral with the operating lever.
In the above mentioned mechanisms, it is possible for the cam to jam in its clamped position against a steel plate after having lifted the same. This particularly occurs after having lifted plates of a thickness at or near the maximum thickness capacity for the particular clamp. This occurs even after the weight has been removed from the clamp and the lifting cable slackens. When so jammed, the cam cannot be released by the operating lever as intended, but first a light or moderate blow must be struck on the end of the lifting or "G" link in order to first free the cam from its jammed condition. Frequently, operators of the clamps will attempt to open such a jammed clamp by striking the operating lever with a hammer or other implement in an effort to move the operating lever to its open position. Such results in damage to either or both of the operating lever or the spring mechanism. This occurs due to the fact that the operating lever in its locked and clamped position or locked on position has passed over center and the additional fact that when lifting plates at and near the maximum thickness capacity for the clamp, the spring is under its maximum compression. Even at the greatest thickness which the clamp can accommodate, there is some compressibility still left in the spring and thus the operating lever may pass over center into its locked on position. When passing over center, the spring is further compressed and then a small amount of the compression is released once the operating lever is in its locked on position. When the crane then lifts the clamp and the plate, the weight of the plate further pivots the gripping cam into still a tighter gripping position; however, this movement compresses the spring still further. When then the plate is set down and the weight removed from the clamp, there is not sufficient compressibility remaining in the spring to permit the operating lever to compress it even the slight amount necessary to pass back over center to the open position. In these clamps the spring is always under some compression, even in its least compressed state. The compression of the spring holds the operating lever in both its locked on and locked open positions.
SUMMARY OF THE INVENTION
The present invention retains the safety features of the prior art clamp while overcoming the possibility of the clamp becoming jammed in its locked on position in such a manner as to prevent the operating lever from being moved to its open position. The present invention also simplifies the prior art devices by using fewer parts of unique design.
To accomplish these ends, the device of the present invention replaces the former spring mechanism with a combination link-spring of novel design. The combination link-spring is pivoted at one end to the radius link and at the other end to the operating lever. Since this combination link-spring is pivoted as mentioned, movement of either the operating lever or the radius link will be transmitted to the spring which, in turn, will either move the other member or absorb the movement within the spring itself or a combination of both, depending upon the relative positions of the parts when the movement is initiated and during such movements.
In particular, the combination link-spring is comprised of two pieces of spring steel ribbon each of which is bent to form a loop at either end and with at least two oppositely directed intermediate bends. These two pieces are then nested together to provide the link-spring which receives a pivot pin on the radius link at one end thereof and a pin on the operating lever at the other end. Intermediate its ends, this composite spring has at least two opposite bends therein to give it a generally "Z" shape. In the preferred embodiment, there are two pairs of oppositely directed intermediate bends giving the preferred spring the appearance of a double "Z".
Because the combination link-spring is pivoted at one end to the radius link and at the other end to the operating lever, the movement of either the radius link or the operating lever will be imparted to the link-spring. The combination link-spring will, in turn, impart none, part, or all of such received movement to the other element. To the extent that the movement of one or the other of the radius link and the operating lever is not wholly imparted to the other thereof, the movement is absorbed by the link-spring, either by compression of the spring or extension and tensioning thereof. Whether none, part, or all of the movement of the radius link or the operating lever is imparted to the other thereof depends upon the relative position of the members at the time of such movement and their design relationship.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation of the clamp of this invention with portions of the housing plate broken away to show the operating mechanism which in this view is in its locked open position;
FIG. 2 is a view similar to FIG. 1 with the device in its locked on position shown in solid lines and its on but not locked position in broken lines;
FIG. 3 is an end elevation taken in the direction of the arrow A of FIG. 2;
FIG. 4 shows the two parts of the combination link-spring used in the device of FIGS. 1-3 removed from the device and positioned beside each other in unnested condition;
FIG. 5 shows the two parts of the link-spring and how they are nested together;
FIG. 6 is a modification of the spring of FIGS. 1-5;
FIG. 7 is a modification of the clamp of FIGS. 1-3 using the novel spring of this invention and shown in locked on position; and
FIG. 8 is the clamp of FIG. 7 shown in locked open position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the figures, FIG. 1 shows a lifting clamp generally indicated at 10 comprised of a two part housing, the two parts of which are facing and matching plates 12 and 14. As shown in FIG. 1, the plate 12 has been broken away to show the operating elements of the device. The two plates 12 and 14 are held in spaced apart condition by means of embossments 16 on each plate extending half way to the other plate and there bearing against a mating embossment as perhaps best shown in FIG. 3. Rivets 18 pass through these embossments 16 and hold the two plates 12, 14 in fixed spaced apart relationship to form a housing. It will be appreciated that the rivets have enlarged ends and the preferred type of securement is a conventional button head rivet although bolts or the like could also be used.
Fixed pivot shafts 20 and 22 also pass through the plates 12 and 14 of the housing and have enlarged heads 24 and 26 respectively bearing against the outside surface of the plate 14 as best shown in FIG. 3 and have cotter pins 28 and 30 respectively passing through said shafts 20 and 22 and bearing against the outside face of the plate 14. Thus the shafts 20 and 22 also aid in maintaining the plates 12 and 14 secured together.
The lifting clamp has the shape generally of an inverted "U" when in use and as shown in FIGS. 1 and 2. The shorter arm of the "U" has mounted therein a pad 32 of known type mounted somewhat loosely in the opening 34 of the shorter arm or jaw in known manner. It will be appreciated that one half of the opening 34 is formed in each of the facing plates 12 and 14 thus completing a generally cylindrical opening when the two plates are matched together. The pad 32 has ridges 36 on its face as is also known.
Pivotally mounted on the shaft 22 in the space between the facing plates 12 and 14 is a gripping cam 40 having a serrated cam shaped face 42 of generally conventional shape. Pivoted on either side of the cam 40 at 38 are a pair of connecting links 50 which are pivoted at their other ends at 44 on either side of a radius link 60 which in turn is pivotally mounted between the facing plates 12 and 14 on the fixed pivot shaft 20 for pivotal movement thereabout. Also pivoted on either side of the radius link 60 at 46 are the legs 47 of a bifurcated lifting link 48. As shown, the lifting link 48 is a chain connector having an opening 52 therein through which a pin (not shown) may be passed for connecting the chain connector 48 to the end of a length of chain suspended from above as from a crane. However, the lifting link 48 may be a shackle with an eye to receive a hoist hook or any other suitable connecting means.
An operating lever 70 is also mounted between the plates 12 and 14 on a fixed pivot 58 which may be a rivet or, as shown, a bolt 58 passing through an opening in the lever 70 and also through an opening in the wall 14 of the housing and having a nut 62 thereon.
THE SPRING
A double link-spring 80 is pivotally mounted at 56 to the lever 70 and at its other end at 54, to the radius link 60. As shown, the spring 80 comprises two nested parts 82 and 84 which are identical pieces of flat ribbon spring steel bent to the shape shown. When nested as shown in FIGS. 1 and 2, the two springs have two bends 64 and 66 opening generally to the left in the figures and two bends 74 and 76 opening generally to the right. The elements 82 and 84 of the combined link-spring 80 each have a small loop 68 at one end and a larger loop 78 at their other end. It will be noted that the larger loop 78 does not quite close, since it must receive the thickness of the other half of the spring.
The spring details are perhaps best shown in FIGS. 4 and 5. As shown in FIG. 4, the spring 80 comprises two identical parts 82 and 84 which are not nested together in the figure. As shown in the figure, the two halves 82 and 84, rest beside each other in the same orientation, i.e., both have their small loop 68 at the top and facing to the left. It is apparent from the figure that both members, 82 and 84, are identical in shape and size. As will also be seen from the figure, the small loop 68 is substantially closed, although it need not be. The large loop 78; however, must be spaced with the gap 86 in order to receive the thickness of the other spring. In the orientation shown in FIG. 4, the springs will not nest. However, if one of them (say the one on the right) is rotated 180° in the plane of the drawing to bring its small loop to the bottom and its large to the top, then one of them may be lifted and placed on top of the other one and the two pieces nested as shown in FIG. 5. For convenience in visualizing this nesting in FIGS. 4 and 5 the spring 84 is shown cross-hatched while the spring 82 is not. It will also be seen from FIG. 5 that the springs comprise a generally double "Z" in shape with the upper bar of the lower "Z" being the bottom bar of the upper "Z". It will also be appreciated that the spring 80 may be longer or shorter by addition of additional bends or the use of fewer thereof. While the spring of FIGS. 1-5 has two bends opening in one direction and two bends opening in the opposite direction, the spring of FIG. 6 has only two bends with one opening in each of two opposite directions.
OPERATION
Having reference to FIGS. 1 and 2, FIG. 1 shows the clamp in its "locked open" position, i.e., in this position, it will not clamp anything placed in the slot between and pad 32 and the gripper cam 40 even if the weight of the clamp is on the chain connector 48 as when hanging from a crane's cable or chain. As shown, the operating lever 70 has been moved to "over center". That is that a line a--a drawn between the axis of the pivot 54 and the axis of the pivot 56 falls to one side (the right in FIG. 1) of the axis of the bolt 58 about which the lever 70 pivots. In the position shown in FIG. 1, the pivot points 54 and 56 are closer together than at any other time during normal operation (except when passing "over center" to the position shown) and the spring 80 is, accordingly, under compression. This compression tends to try to rotate the lever 70 in the clockwise direction as shown in FIG. 1 due to the position of line a--a with respect to the axis of pivot 58, but further movement clockwise is prevented by the abutment of the end of the lever 70 against a stop which, as shown, is one of the embossments 16 of the housing. In the opposite direction, the spring 80 tends to try to rotate the radius link 60 clockwise about the pivot 20, but it is prevented from doing so due to the fact that the axis of the pivots 54 and 20 are close together and as such the mechanical advantage is slight. Of course, alignment of the pivots 44, 38 and 22 represents the apparent theoretical geometric limit of clockwise rotation of the radius link 60. However, such condition is to be avoided lest upon release from the locked open position the link turn the cam the wrong way. A stop 41 is provided to insure against such happening, but in the embodiment shown the moment of force exerted by spring 80 to move radius link 60 clockwise, while sufficient to move the several parts to or close to the position shown, is not normally sufficient to move them the last small increment necessary to bring the back of gripper cam 40 up against stop 41.
In the broken line position shown in FIG. 2, the lever is in its on or closed position, but it is not locked on. There are two safety features to this position. In this position, the operating lever 70 extends noticeably from the clamp and can be spotted even by a crane operator some distance away. He then knows that the clamp is not properly locked on. To aid in such observance, the end of the lever may be large and painted a bright color such as red or orange. A second safety feature of this position is that while the clamp is not locked on, it can still safely lift a plate since upward movement on the lifting link 48 rotates the radius link counterclockwise and the cam 40 clockwise into tight engagement with a plate between it and the pad 32. This occasionally happens when a plate is being lifted from the horizontal position if the operator of the clamp is careless and does not properly lock the clamp in its locked position as shown in solid lines in FIG. 2.
As shown in FIG. 2, the lever 70 has been moved counterclockwise from its position of FIG. 1 through the broken line position shown in FIG. 2 to the solid line position of FIG. 2 where it bears against a stop 72 extending inwardly from the housing plate 14. Again, the lever 70 has moved "over center" in which a line b--b drawn between the axes of pivots 54 and 56 lies to the right of the axis of bolt 58. In this position, however, the spring is in tension and tends to try to move the lever 70 counterclockwise due to the position of line b--b with respect to the axis of bolt 58, thus holding it against the stop 72. This tension also tends to try to rotate the radius link 60 in a counterclockwise direction, thus imparting through the connecting link 50 a clockwise movement to the cam 40 thus tending to make it bear against any plate P positioned between the cam 40 and the pad 32. Accordingly, when the clamp and operating lever are in their locked open position as in FIG. 1, the spring 80 is under compression, when the parts are in their on but not locked condition shown in broken lines in FIG. 2 the spring is under neither compression nor tension and when the parts are in their locked on position as shown in solid lines in FIG. 2 the spring is under tension. It should also be noted that lifting through the lifting link 48 upwardly even with a maximum load, (i.e., a plate of maximum thickness), tends to slightly reduce the tension in the spring 80 and, accordingly, after such a lifting the slight additional tension created when moving the lever 70 clockwise out of its locked on position is readily achieved as it passes over center (the axis of the bolt 58) to release the gripper cam and the plate which had been lifted. Accordlingly, while it is possible when lifting a plate of maximum thickness for the gripper cam 40 to be tightened to such an extent that the operating lever 70 cannot release the cam 40 from the plate P, the operating lever 70, in such a situation, can nevertheless be easily moved out of the locked on position to the neutral position and to the locked open position. Thus the operator will not be tempted to strike on the operating lever to vainly try to release it as was priviously the case.
Also, when the gripper cam does tighten up as just described the operating lever 70 can be moved to the locked open position in which the link-spring 80 will then be severly compressed. In this position the link-spring 80 is exerting a force counterclockwise (in FIGS. 1 and 2) in an effort to open the gripper cam 40. The clamp 10 need then be merely shaken or jiggled or the casing struck a light blot to release the cam's bite on the plate. Previously, when this occurred the operating lever was jammed as well and the spring mechanism exerted pressure tending to hold the gripper cam against the plate.
When in the present device such jamming occurs and the operating lever is moved to the locked open position the link-spring 80 is, as mentioned, severely compressed. When then the clamp is jiggled to break the bite of cam 40 on a Plate P, then the spring returns the linkage and cam to locked open position with considerable force. If the parts are worn there is danger that the parts will "overtoggle" i.e. move to a position where the axis of pivot 38 is on the other side (to the left in FIG. 1) of a line drawn between the axes of pivots 22 and 44. To prevent this from occurring the stop 41 is provided.
CLAMP MODIFICATION
In FIG. 7 is shown a modified clamp similar to that of FIGS. 1-3 which utilizes a cam arrangement to hold the gripper cam in engagement with a steel plate being lifted and against possible opening when the weight of the plate is removed from the clamp as when the plate is set down upon the floor or other support. While the preferred embodiment of FIGS. 1-3 accomplishes the same purpose in its locked on position due to the tension of the link-spring 80, the invention is also applicable to clamps disclosed in the prior art which use a cam arrangement for this purpose. U.S. Pat. Nos. 2,852,300 and 3,857,600 disclose clamps which use cams to lock the gripper cam in contact with a plate.
In FIG. 7, parts which are substantially identical to or are analagous to like parts in the embodiment of FIGS. 1-3 are numbered with the same numerals with the prefix 1. That is to say by adding 100 thereto. The link-spring 180, for example, is like the link-spring 80 of FIGS. 1-3 excepting that it has 3 pairs of bends with one bend of each pair facing in one direction and the other bend of each pair facing in the opposite direction. Accordingly, there are six bends with three facing to the left in FIG. 7 and three facing to the right.
The structure of the modified clamp of FIG. 7 is much like that of the FIGS. 1-3 embodiment excepting that in the FIG. 7 clamp there is a cam means arranged between the operating lever 170 and the gripping cam 140. The gripping cam 140 has on a hub thereof a cam surface 190 that is circular and concentric to the axis of the shaft 122 about which the gripper cam 140 pivots. Cooperating with the cam surface 190 is an arcuate cam surface 192 on a pivoted cam 194 pivoted at 196 on a suitable fixed pivot such as a bolt passing through the faceplate 114 (the broken away faceplate closest to the viewer in FIG. 7). Adjacent its other end cam 194 is pivoted at 159 to operating lever 170 by any suitable means such as the bolt and nut shown. This pivot 159 serves as a "floating pivot" in that it can move about the axis of pivot 196. As shown in FIG. 7, the operating lever 170 is against a stop 172 and is held in that position by virtue of the fact that the link spring 180 is tensioned and a line c--c drawn between the pivot points 154 and 156 lies to one side (to the left as viewed in FIG. 7) of the floating pivot 159. Thus, the operating lever 170 is being held against the stop 172 by the tension in the spring 180. The link-spring 180 is also applying a force to cam 194 in a counterclockwise direction but the cam cannot rotate due to engagement of cam surface 192 with cam 190. The clamp is in its locked on position.
In this position of the parts, the point 200 where the cam surfaces 190 and 192 contact, is above a line e--e drawn between the axes of the pivots 122 and 196. The arcuate surface of the cam 192 is chosen to ensure that the point 200 where the two cam surfaces 190 and 192 are in contact is always above the line e--e regardless of the thickness of the plate P being gripped. Because of this position, any attempted clockwise rotation of the gripper cam 140 about its pivot shaft 122 is prevented even when the plate is set down. Accordingly, the gripper cam 140 is fixed against the plate in gripping fashion until such time as the operating lever 170 is rotated counterclockwise about its pivot 159. When this occurs there is a force applied both by spring link 180 and the operator to rotate the cam 194 counterclockwise as well, but since the cam surface 192 is bearing on cam surface 190 the rotation of cam 194 is prevented. As such, the only motion possible is for operating lever 170 to rotate counterclockwise about its pivot 159 which is for the time being essentially fixed. As this movement continues, however, a point is reached where the axes of pivots 196, 159, and 156 all lie on the same line and at about this point or soon thereafter the link-spring 180 is in a neutral position being neither compressed nor tensioned. Further counterclockwise movement of operating lever 170 by the operator soon brings the pivot 156 to a point where a line drawn between its axis and the axis of pivot 196 lies above pivot 159 at about this point or soon thereafter the link-spring 180 begins to resist further counterclockwise movement of the operating lever 170. At this point the pivot 156 serves substantially as a fixed pivot and counterclockwise movement of the operating lever 170 imparts a downward movement to pivot 159 and a clockwise rotation to the cam 194. This rotation causes cam 194 to release the gripper cam 140 and come up against the stop 198 and thus the pivot 159 is again temporarily fixed but this time in the position of FIG. 8. The continued counterclockwise rotational movement of operating lever 170 by the operator compresses the link-spring 180 thus applying a counterclockwise rotation to the radius link 160 and through it and links 150 a clockwise force to the gripper cam 140 moving it out of engagement with a plate positioned in the clamp. The final movement of lever 170 counterclockwise brings the lever 170 against the stop 116 and so positions the pivot 156 that the line d--d drawn through it and pivot 154 lies to the left of the axis of pivot 159. This position is shown in FIG. 8. In this position the link-spring is applying a force to lever 170 counterclockwise about pivot 159 but movement is prevented by stop 116. The link-spring is also applying a force clockwise to the cam 194 but movement is prevented by stop 198. The compression force in the link-spring 180 is also trying to rotate the radius link 160 counterclockwise and the gripper cam 140 clockwise but these have either reached the limit normally obtainable or the back of cam 140 has come up against stop 141. The clamp is in its locked open position.
When the operator moves the operating lever 170 clockwise to apply the clamp to a plate the lever 170 initially pivots about the temporarily fixed pivot 159. This moves pivot 156 clockwise about pivot 159 and thus moves line d--d to the right to a point where the lever 170 has again moved over center and the line d--d lies to the upper right of pivot 159. Further clockwise rotation of lever 170 decreases the compression in the link-spring steadily until it is under neither compression nor tension. Shortly thereafter the link-spring 180 begins to resist further rotation of the operating lever 170. As this resistance begins further rotation of operating lever 170 does two things. First, it applies an upward force on pivot 159 and thus a rotational force is applied to cam 194 tending to rotate cam 194 counterclockwise. Second, the tension applied through link-spring 180 tends to rotate radius link 160 clockwise and thus through links 150 a counterclockwise force is applied to gripper cam 140. Both of these two sets of motions begin substantially simultaneously, but very little movement of cam 194 is required and very little force is necessary to complete its rotation. As such the cam 194 will complete its rotation very quickly thus bringing cam surface 192 into engagement with cam surface 190 well before gripper cam 140 has completed its rotation into engagement with a plate.
Once cam 194 has moved to engage cam surface 190 the pivot 159 is again temporarily fixed in the position of FIG. 7. Continued clockwise movement of operating lever 170 by the operator then continues to move radius link 160 clockwise and through links 150 the gripper cam 140 continues to move counterclockwise until it engages a plate. Further clockwise rotation of lever 170 by the operator applies tension to link-spring 180 which in turn applies clockwise rotational force to radius link 160 and thus applying force to hold gripper cam 140 tightly against the plate. The final movement brings all of the parts to the position shown in FIG. 7 with the link-spring 180 in tension and the pivot 159 lying to the right of line c--c and lever 170 up against stop 172 as above described. The clamp is in its locked on position.
It will be appreciated by those skilled in the art that in the embodiment of FIGS. 7 and 8 the gripper cam 140 is held in engagement with a plate not only by the tension in link-spring 180 as in the case with the embodiment of FIGS. 1-3, but also is locked in place by the cam 194. Any action tending to rotate gripper cam 140 clockwise out of engagement with a plate such as when the plate is set down will try to rotate cam 194 counterclockwise but due to the arcuate shape of cam surface 192 such a force only causes cam 194 to bear even harder against cam surface 190. The force is transmitted to and resisted by the fixed pivots 122 and 196.
It will be understood by those skilled in the art that the modification shown in FIGS. 7 and 8 is particularly useful for clamps designed for lifting very heavy plates of, say, 2 to 5 tons or more. In such cases it may prove difficult to design a Z spring that would have enough force in tension to adequately hold the gripper cam in engagement with a plate while still being capable of manual operation by the operator to move the operating lever to and from the locked on and locked open positions. In such event the modification of FIGS. 7 and 8 provides the added holding strength of the cam 194 to insure a tight grip without requiring an excessively powerful spring. | A locking type of lifting clamp for lifting steel plates is disclosed in which there is provided the usual clamp body with a pivoted gripping cam pivotally mounted to extend across a slot into and out of engagement with a steel plate to be lifted. This cam is operated by a connecting link pivoted at one end to the cam and at the other end to a radius link which is itself pivoted to the clamp body. Pivoted to one end of the radius link is the lifting link which connects the same with the lifting shackles of a crane or the like. An operating lever is also pivoted to the clamp body and connected to the radius link by means of a combination link - spring pivoted at one end to the operating lever and at the other end to the radius link. The combination link - spring comprises a two part member made from spring steel bent into a generally double "Z" shape and in which the two parts are identical and nested together. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates generally to a method and apparatus for monitoring fuel cell voltages in a fuel cell stack, and more particularly to making connector and component failures in the monitoring circuitry transparent to the user without losing the information that the failed connector or component was designed to provide. Furthermore, the method and apparatus provide for a redundant power supply and ground connection for the monitoring circuitry measurements.
Fuel cells produce energy by the electrochemical processing of reactants and the subsequent generation of electric current. A typical fuel cell configuration includes a polymer membrane (e.g., a proton exchange membrane (PEM)) with catalyst layers on both sides to promote the respective oxidation and reduction of hydrogen and oxygen. Additional components, including a pair of gas diffusion media layers disposed against the respective catalyst layers and cathode and anode bipolar plates placed outside the gas diffusion media layers; these bipolar plates define flow channels therein to facilitate the introduction of the externally-provided reactants to the catalyst-coated PEM. The various components are compressed together to form the fuel cell. To increase the power output, numerous fuel cells are arranged together to form a fuel cell stack.
Fuel cell stacks are monitored for their electrical viability through a set of diagnostic connectors which are attached to the bipolar plates of each fuel cell within the fuel cell stack. An embedded measurement module (EMM), via the diagnostic connectors, monitors the voltage of each fuel cell and reports that health to the vehicle electronic control unit (ECU).
A problem with this approach is that the EMM is unable to address any failure modes that may arise, making the system vulnerable to diagnostic connector and component failures. Furthermore, if the diagnostic connector that powers the EMM fails, the EMM will not provide any information on any of the fuel cells to the vehicle ECU. A way is needed to circumvent those failures to get the needed data to monitor the health of the fuel stack.
SUMMARY OF THE INVENTION
In view of the above and other problems, the present disclosure modifies the end of frame sequence of the pulse width modulation (PWM) signal to provide a new data set to be used in calculating the voltage of each fuel cell connected to the EMM in the event of a connection or component failure. The role of the end of frame sequence is to provide a calibration signal and to indicate the beginning of a data stream. In the preferred embodiment, the end of frame sequence is modified to add a total voltage value of all the fuel cells connected to the EMM. In the event of a connection or component failure, the sum of all the fuel cell voltages reported are subtracted from the total voltage value to find the missing fuel cell voltage due to the failure. Furthermore, a redundant or alternate power and ground connection are added to the current EMM architecture to overcome a failure in the primary power or ground connection.
According to a first aspect of the present invention, a redundant health monitoring system is disclosed. The system uses an EMM with a cell voltage monitoring circuit and a plurality of diagnostic connectors. The plurality of diagnostic connectors are coupled to a substrate and electrically connected with a plurality of fuel cells in the fuel cell stack. The cell voltage monitoring circuit is configured to send a plurality of pulses and an end of frame sequence to a receiver circuit. Each pulse in the plurality of pulses corresponds to an individual voltage for an individual fuel cell in a plurality of fuel cells in the fuel cell stack. The end of frame sequence indicates the beginning of the plurality of pulses as well as a total voltage for the plurality of fuel cells connected to the EMM. A central processing unit with an algorithm programmed therein sums up the individual voltages and the sum is subtracted from the total voltage to determine a missing voltage of at least one fuel cell.
According to a second aspect of the present invention, a method of redundant health monitoring of a fuel cell stack is disclosed. The method entails providing an EMM that is electrically connected to a plurality of fuel cells in the fuel cell stack. The EMM sends out a plurality of pulses wherein each pulse in the plurality of pulses indicates an individual voltage for an individual fuel cell in a plurality of fuel cells in the fuel cell stack. An end of frame sequence is defined that indicates the beginning of the plurality of pulses, and a total voltage for the plurality of fuel cells connected to the embedded measurement module. A missing voltage value is calculated corresponding to at least one of the fuel cells in the fuel cell stack using an algorithm. The individual voltages for each fuel cell are added up to a sum of the individual voltages and the sum is subtracted from the total voltage to determine the missing voltage value.
According to a third aspect of the present invention, a redundant health monitoring system for a fuel cell stack is disclosed. The system uses an EMM with a cell voltage monitoring circuit and a plurality of diagnostic connectors. The plurality of diagnostic connectors are coupled to a substrate and electrically connected with a plurality of fuel cells in the fuel cell stack. The cell voltage monitoring circuit is configured to optically send a plurality of pulses and an end of frame sequence to a receiver circuit. Each pulse in the plurality of pulses corresponds to an individual voltage for an individual fuel cell in a plurality of fuel cells in the fuel cell stack. The end of frame sequence indicates the beginning of the plurality of pulses as well as a total voltage for the plurality of fuel cells connected to the EMM. A central processing unit with an algorithm programmed therein sums up the individual voltages and the sum is subtracted from the total voltage to determine a missing voltage of at least one fuel cell. The EMM has a primary power source and a redundant or alternate power source. The redundant power source is configured to use at least one diode electrically connected to an individual diagnostic connector from the plurality of diagnostic connectors to provide the alternate power source for the EMM. The embedded measurement module also has a primary ground connection and a redundant or alternate ground connection. The redundant ground connection is electrically connected to at least one individual diagnostic connector from the plurality of diagnostic connectors to provide the alternate ground source for the EMM.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is a schematic block diagram of a fuel cell system with health monitoring apparatus according to an aspect of the disclosure;
FIG. 2 depicts a PWM signal that includes an index synchronization sequence and cell voltage pulses; and
FIG. 3 depicts a comparison between a cell voltage measurement signal including an index synchronization sequence, a saw tooth comparison signal and an output signal.
DETAILED DESCRIPTION
Referring first to FIG. 1 , a schematic block diagram of a fuel cell system 10 is shown. The fuel cell system 10 has a fuel cell stack 12 , an embedded measurement module (EMM) 26 and a receiver circuit 30 . In this non-limiting embodiment, fuel cell stack 12 has a plurality of stacked fuel cells 14 . The EMM 26 comprises a stack interconnect 16 having a plurality of diagnostic connectors 18 and a cell voltage monitoring circuit 28 . The diagnostic connectors 18 are mounted to a substrate and are in electrical contact with a plurality of bipolar plates 20 that separate the fuel cells 14 in the fuel cell stack 12 . In one non-limiting embodiment, the stack interconnect 16 includes twenty diagnostic connectors 18 . All twenty diagnostic connectors 18 are in contact with seventeen bipolar plates 20 which define sixteen fuel cells 14 . This enables the EMM 26 to monitor the voltage of sixteen fuel cells 14 . Those sixteen fuel cells are represented in FIG. 1 as 14 A- 14 P and define a cell group 15 . Seventeen of the diagnostic connectors 18 are in contact with seventeen bipolar plates 20 . The remaining three diagnostic connectors 18 make redundant connections to three of the seventeen bipolar plates 20 . In one embodiment, the stack interconnect 16 is an embedded interconnect that is part of the fuel cell stack 12 , although other types of interconnects may be equally applicable.
The EMM 26 is created with a standard twenty diagnostic connectors 18 . The architecture of the fuel cell stack 12 encompasses three hundred and twenty fuel cells 14 . Using an even twenty EMMs 26 to monitor the fuel cell stack 12 , each EMM 26 will monitor sixteen fuel cells 14 , leaving three diagnostic connectors 18 on each EMM 26 free for other purposes.
The cell voltage monitoring circuit 28 comprises a communication module 44 , a power supply 48 , and a pulse generator (discussed in more detail below). The communication module 44 in this non-limited example uses a LED to communicate optically. The communication module 44 may also use electrical or radio frequency to communicate as well.
A power supply 48 provides the electricity needed for the EMM 26 to operate. The EMM 26 derives its power directly from the fuel cell stack 12 through two dedicated connections in the diagnostic connector 18 . One connection is for power and the second is for ground. In the preferred embodiment, an alternate power source 58 provides power directly from the fuel cell stack 12 in the event of a connection or component failure. The alternate power source 58 is provided from a redundant diagnostic connector via one of the plurality of leads 32 . At least one diode 59 is connected to an individual diagnostic connector from the plurality of diagnostic connectors 18 and at least one diode 59 is connected from one of the plurality of leads 32 to the power supply 48 to create the alternate power source 58 . As used throughout this application, the alternate power source 58 is also a redundant power source.
In the preferred embodiment, an alternate ground connection 53 is provided to ensure the EMM 26 has a connection to ground in the event of a connection or component failure. The alternate ground connection 53 is directly connected from the fuel cells 14 via one of the plurality of leads 32 . The alternate ground connection is provided from the redundant diagnostic connector and connects directly to the power supply 48 . As used throughout this application, the alternate ground connection 53 is also a redundant ground connection.
Another component of the cell voltage monitoring circuit 28 is the pulse generator. The pulse generator comprises a multiplexer 34 , an instrumentation amplifier 38 , a saw tooth wave generator 42 , a counter circuit 36 , a comparator 40 , and a reference circuit 50 . The components of the pulse generator are described in greater detail below.
In the cell voltage monitoring circuit 28 , the plurality of leads 32 is electrically coupled to each diagnostic connector 18 in the stack interconnect 16 . An opposite end of each lead 32 is electrically coupled to the multiplexer 34 that selectively provides two voltage potential signals from the diagnostic connectors 18 to the instrumentation amplifier 38 at any given point in time. The counter circuit 36 provides sequence signals to the multiplexer 34 to cause the multiplexer 34 to selectively and sequentially switch from one of the leads 32 to a next one of the leads 32 . The output of the multiplexer 34 is amplified in the instrumentation amplifier 38 such that the signal has a magnitude that identifies the voltage of the particular fuel cell 14 being measured. The amplified cell voltage signal is provided to the comparator 40 that compares the signal to an inverted saw tooth wave provided by the saw tooth wave generator 42 , where the output of the comparator 40 is a PWM signal. The PWM signal is shown in FIG. 2 . The PWM signal has two parts; a series of end of frame synchronization pulses and a data stream. The width of the pulses in the data stream define a cell voltage as will be discussed in detail below. The PWM signal is provided to the communication module 44 that generates a communication signal 46 having an on/off time determined by the pulses.
The data stream is a sequence of pulses wherein each pulse corresponds to a voltage measurement of each fuel cell 14 in the cell group 15 . The end of frame sequence is introduced into the PWM signal after a last fuel cell 14 P voltage measurement pulse so that it provides an indication that the next pulse after the end of frame sequence is the voltage measurement pulse for a first fuel cell 14 A in the cell group 15 . The cell voltage monitoring circuit 28 of the type being discussed sequentially measures the voltage of the plurality of fuel cells 14 in order in a cell group 15 . When the voltage of the last fuel cell 14 P in the cell group 15 is measured, the sequence returns to the first fuel cell 14 A in the cell group 15 and begins to measure the voltage, sequencing through the cell group 15 in this manner at the rate set by the saw tooth wave generator 42 .
FIG. 2 is a graph with time on the horizontal axis and magnitude on the vertical axis showing the PWM signal 60 of the type that is output from the comparator 40 . The end of frame synchronization pulses 64 provide a reference pattern that when decoded provides an indication that the data stream 190 is next. The first cell in the cell group (refer to FIG. 1 ) will be the first signal 194 in the data stream 190 after the end of frame synchronization pulses 64 and the last signal 196 corresponding to the last cell in the cell group with end of the data stream 190 . The format or pattern of the frame synchronization pulses 64 in this embodiment is a high pulse 66 followed by a low pulse 68 , followed by a high pulse 66 and then followed by a last pulse 198 (H-L-H-L). This pattern is specifically selected to provide a defined sequence of the end of frame synchronization pulses 64 that is very unlikely to occur in the actual voltage measurements of the fuel cells shown in FIG. 1 , thus providing a good indication that the pulses are the end of frame synchronization pulses 64 . In the preferred embodiment, the pulse width of the first three end of frame synchronization pulses 64 (H-L-H) may always be the same for the high pulses 66 and the low pulses 68 . The pulse width of the last pulse 198 of the end of frame synchronization pulses 64 may be used to indicate the total voltage of the cell group. The last pulse 198 may not have the same pulse width as the first three pulses 66 and 68 . The pulse width of the pulses 62 of the data stream 190 is created by the actual voltage of the fuel cells in the cell group, as will be discussed in detail below.
The width of the end of frame synchronization pulses 64 may be chosen so that the magnitude of the pulse width is known, consistent and outside of any possible pulse width of the data stream 190 . In one non-limiting example, the width of the high pulses 66 represents 1.235V and the width of the low pulse 68 represents −1.235V. The modulation provided by the saw tooth wave ( FIG. 3 ) creates the PWM signal 60 so that the high voltage has a narrow pulse width and the low voltage has a wide pulse width.
In the present disclosure, the pulse width of the last pulse 198 of the end of frame synchronization pulses 64 is modified to indicate a total voltage measurement of all the fuel cells in the cell group in FIG. 1 . The total voltage measurement is larger in magnitude than any single voltage measurement of the cell group in the data stream 190 . The magnitude of a total voltage measurement serves two functions. The first is the traditional function of indicating the end of the data stream 190 . The second is an actual, useable total voltage measurement that can be interpreted and used by the electronic control unit (ECU).
The end of frame synchronization pulses 64 can be injected into the PWM signal 60 in any suitable matter. In the fuel cell system 10 , the reference circuit 50 generates the sequenced values that become the end of frame synchronization pulses 64 . The counter circuit 36 sequences the signals from the reference circuit 50 into the PWM signal 60 after the last fuel cell 14 P in the cell group 15 is measured. The total voltage measurement is provided to a series of pins on line 52 to the multiplexer 34 which presents the voltage values in sequence to the instrumentation amplifier 38 and then to the comparator 40 . The differentiation between the high pulses 66 , the low pulse 68 and the last pulse 198 end of frame synchronization pulses is provided by the modulation using the saw tooth wave 70 shown in FIG. 3 and discussed in more detail below.
The end of frame synchronization pulses 64 allow the voltage measurements to be calibrated, in this non-limiting example, 250 times per second. In other words, the amount of time that the pulse is high is compared to the high pulse 66 to give the voltage measurement that will be less than that value. Because the sequence of the end of frame synchronization pulses 64 represents a start for the data stream 190 , and those measurements are taken in the order of the fuel cells 14 in the fuel cell stack 12 , each pulse 62 specifically identifies which fuel cell 14 in the cell group 15 being monitored is associated with that pulse 62 .
FIG. 3 is a graph with time on the horizontal axis and magnitude on the vertical axis showing a relationship between the inputs to the comparator 40 to provide the modulation of the cell voltage measurement signals and the communication signal 46 that is output from the communication module 44 . At the top of FIG. 3 , the saw tooth wave 70 from the saw tooth wave generator 42 is shown super-imposed over a voltage signal 72 from the instrumentation amplifier 38 . Section 74 of the voltage signal 72 includes four square wave pulses that are the end of frame synchronization pulses provided by the reference circuit 50 . When those four square wave pulses are modulated by the saw tooth wave 70 , the end of frame synchronization pulses are produced as shown in FIG. 2 . The positive portion 76 of the voltage signal 72 will become the narrow width pulses 80 of the communication signal 46 and the negative portion 78 of the voltage signal 72 will become the wide width pulses 82 of the communication signal 46 .
In the preferred embodiment, if the saw tooth wave 70 is greater in magnitude than the voltage signal 72 , then the comparator outputs a pulse 62 , which causes a LED in the communication module to conduct and generate the optical signal. This is shown by the bottom of the graph on FIG. 3 where “1” represents the LED being on and “0” represents the LED being off. Particularly, the angle provided by the saw tooth wave 70 creates the modulation for the width of the pulse being relative to the magnitude of the voltage measurement signal. Therefore, the pulses of the optical signal are narrower for the high voltage than they are for the low voltage. As the magnitude of the voltage pulse 84 goes up, it is covered by a narrower part of the saw tooth wave 70 , which creates a narrower pulse in the optical signal. Thus, the greater the magnitude of the voltage pulse 84 represented by a higher voltage of the particular fuel cell being measured, the narrower the pulse for that voltage measurement, which represents a higher voltage.
Referring back to FIG. 1 , in the preferred embodiment using optical communication, the receiver circuit 30 includes a series of receiver channels where there is a single channel 90 for each of the EMMs 26 . Each channel 90 includes a photodiode 92 that receives the communication signal 46 and a trans-impedance amplifier 94 that converts the diode current to a representative voltage. The voltage signal from the trans-impedance amplifier 94 is then sent to a comparator 96 to make sure it is within a desired range, and if so, is then sent to a master central processing unit (CPU) 98 , which receives the signals from all of the channels 90 . The CPU 98 decodes the on/off sequence of the voltage signal to identify the end of frame synchronization pulses 64 so that each new group of actual voltage measurement signals are recalibrated to the startup calibration sequence at each measurement. The CPU 98 uses the width of the voltage pulses that have been decoded to identify a minimum cell voltage, a maximum cell voltage, an average cell voltage, and the actual voltage of each cell. This information is provided to a dual controller area network (CAN) 100 that provides the information to a vehicle bus through a serial interface circuit (SIU) 102 and then to a vehicle ECU (not shown) that controls the fuel cell system 10 , such as controlling reactant flow rates, stack relative humidity, etc. The edge-to-edge time of the PWM signal 60 does not exceed the capability of the timer capture unit in the CPU 98 .
While certain representative embodiments and details have been shown for purposes of illustrating the invention, it will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention, which is defined in the appended claims. For example the communication between the EMM 26 and the receiver circuit 30 could be done electrically via wires, radio waves or optically as illustrated. Furthermore the substrate can be a printed circuit board. | A health monitoring system for a fuel cell stack using current fuel cell architecture to enable the electronic control unit (ECU) to continue to monitor the health of the fuel cell stack despite a component failure. The system uses an embedded measurement module (EMM) connected to a group of fuel cells in the fuel cell stack to monitor the health of that group of fuel cells. The EMM produces a pulse width modulation signal that is sent to the ECU. A total voltage value for the group of fuel cells is embedded into the calibration signal or end of frame sequence. The ECU uses an algorithm to determine a missing voltage of at least one fuel cell in the event of the component failure of that fuel cell by adding up the cumulative value for each fuel cell reporting their voltage and subtracting that value from the total voltage value found in the end of frame sequence. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to the field of shingle removing apparatus in general, and in particular to a powered shingle removing machine, which is pushed across a shingled roof, and which uses a powered, oscillating blade mechanism to lift and remove previously installed shingles.
Residential and commercial building constructions generally have roof decks which are covered with a protective layer of shingles. Shingles are generally placed in overlapping, aligned rows and the shingles are secured in place by a combination of nails, staples or other fasteners and adhesive.
Any shingle, regardless of type, will eventually deteriorate due to exposure to ultraviolet light from the sun, moisture from precipitation, etc. While it is common to install a second layer of new shingles over a single existing layer, eventually the older shingles must be removed for roof refurbishing. Building codes will typically limit the permissible number of shingle layers. This is a physically demanding task when performed by hand without the use of power machinery. Generally, various manually operated scraping tools, such as modified flat shovels, are used to wedge between the shingles and the underlying roofing paper or sheathing, with the front edge of the shovel shearing or pulling the roofing nails which held the shingles in place and breaking adhesive bonds between shingles. The physical effort involved, particularly when performed on a steep sloping roof, is taxing.
As any roofer is all too well aware, mechanical shingle removing devices substantially reduce the amount of physical exertion that is required to strip shingles from a roof. However, they are also difficult to maneuver on a roof surface due to the fast and continuous oscillating movement of the blade. Thus, the workman must stop the motor to push the machine forward for removing additional shingles, which slows the removal process and increases the cost of removal.
It is therefore desirable to provide a shingle removing apparatus which improves the driving mechanism and improves the time efficiency and workman efficiency for removing shingles.
Accordingly, the present invention is directed to a shingle removing apparatus which overcomes one or more of the problems as set forth above.
BRIEF SUMMARY OF THE INVENTION
The present invention overcomes many of the shortcomings and limitations of the prior art devices discussed above and teaches the construction and operation of several embodiments of a shingle removing apparatus adapted for continuously removing the shingles without having to stop the motor to move removal apparatus. The present apparatus can improve the overall efficiency of the entire shingle removing process as compared to the prior art with respect to work efficiency.
In one aspect of the present invention, the present shingle removing apparatus includes a handle, a stripper member, a drive assembly and a drive linkage assembly with lost motion mechanism. The handle has a proximal end and a distal end. The stripper member is adapted for inserting under a shingle and has a first end portion and a second end portion. The first end portion of the stripper member is operatively coupled to the proximal end of the handle such that the second end portion of the stripper member is reciprocally moveable up and down. The drive assembly drives at least a portion of the stripper member and the drive linkage assembly causes at least a portion at a free end of the stripper member through a lost motion mechanism to reciprocally move up and down to thereby remove shingles. The drive assembly is operatively connected to the stripper member to selectively effect pivoting movement of the stripper member relative to the handle. The lost motion mechanism allows the stripper member to intermittently not be driven. The drive linkage assembly in one embodiment comprises a crank arm, a first link and a second link to provide lost motion connection. The crank is coupled to the drive assembly for rotation thereby.
In another aspect of the present invention, the drive linkage assembly provides a lost motion connection between a crank arm and a link arm. The crank arm is pivotally coupled to the drive assembly. The link arm has first and second end portions, and includes an elongated slot spaced from the second end portion. The crank arm is pivotally associated with the slot so as to provide lost motion connection. The second end portion of the link arm is operatively engaged with the stripper member.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a side view of a first embodiment of the present shingle removing apparatus constructed in accordance with the teachings of the present invention.
FIG. 2 is a perspective side view of the shingle removing apparatus of FIG. 1 .
FIG. 3 is a side view of the shingle removing apparatus of FIG. 1 .
FIG. 4 is an exploded perspective view of the drive link assembly in accordance with the teachings of the present invention.
FIG. 5 is a side view of the gear assembly of one housing portion of the shingle removing apparatus of FIG. 1 with portions broken away to show internal detail.
FIG. 6 is a perspective view of another embodiment of the stripper removing apparatus.
FIG. 7 is an exploded perspective view of a drive link assembly.
It should be understood that the drawings are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In certain instances, details which are not necessary for an understanding of the present invention or which render other details difficult to perceive may have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. Like numbers utilized throughout the various Figures designate like or similar parts or structure.
DETAILED DESCRIPTION OF THE INVENTION
The present invention involves the provisions of a shingle removing apparatus wherein the drive linkage assembly includes a lost motion mechanism that effects intermittent movement of the stripper member during continuous rotation of a crank arm so that an operator does not need to stop a motor to go forward for removing more shingles. The present shingle removing apparatus improves the overall efficiency of the shingle removing job as compared to the prior art apparatus with respect to time efficiency and worker efficiency in removing the shingles.
As best shown in FIGS. 2-4 , the shingle removing apparatus 10 comprises a drive system including a drive assembly 80 and a drive linkage assembly 40 . The apparatus 10 includes a stripper member 50 , such as a stripping blade, preferably having a toothed free end portion 52 for inserting under shingles. The shingle removing apparatus 10 is generally operated by using the drive assembly 80 , whereby the stripper member 50 lift nails out of a roofing substrate. As illustrated in FIG. 1 , the shingle removing apparatus 10 of the present invention is positioned on the surface from which material is to be removed such as a shingled roof. The operator positions himself or herself behind the shingle removing apparatus 10 . The operator grips the handle 20 and may advance the shingle removing apparatus 10 on wheels 53 . The shingle removing apparatus 10 is actuated by depressing a trigger 62 which will energize a motor 60 causing a drive shaft 25 to rotate. The drive assembly 80 will effect an oscillatory and reciprocal motion to the stripper member 50 through the drive linkage assembly 40 . The operator, by use of the grip 23 and/or handle 20 , advances the leading edge 51 of the stripper member 50 beneath the roofing material to be removed. As the leading edge 51 contacts the underside of the shingles 1 , the shingles 1 and any fasteners are lifted upwardly along with the fastener such as staples or nails. After the leading edge has lifted a section of shingles 1 from the surface, the operator proceeds forward so that the stripper member 50 is positioned between the next remaining layer of shingles 1 and removal is accomplished in a similar manner.
Referring to the drawings more particularly by reference numbers, the numeral 10 in FIGS. 1-3 identifies one embodiment of a shingle removing apparatus.
In one aspect of the present invention, the shingle removing apparatus 10 includes a handle 20 , a drive assembly 80 , a drive linkage assembly 40 and a stripper member 50 for forcibly removing shingles 1 as illustrated in FIGS. 1-7 . The handle 20 comprises an elongated tubular housing 22 , an on/off switch such as a trigger 62 disposed adjacent its distal end portion 24 , a transversely extending secondary handle 23 disposed on its intermediate portion and a mount member 54 disposed on its proximal end portion 26 . The handle 20 is hollow and can have an internal bearing (not shown) for supporting a drive shaft 25 . The stripper member 50 can be a shingle removing blade, which is operatively coupled to the drive assembly 80 for effecting movement of the stripper member 50 relative to the handle 20 through the drive linkage assembly 40 . The stripper member 50 is in the form of a plate with teeth 52 on the leading edge 51 . The stripper member 50 has a leading edge 51 which engages the shingles and fasteners to be removed. A stripper member 50 has a trailing edge portion and the beveled free end 51 .
The shingle removing apparatus 10 is powered by the motor 60 which may be hydraulic, pneumatic or electric with controls suitably located on the handle 20 . The motor 60 can be secured to the free end portion 24 of the handle 20 by a bolt 65 and a bracket 63 . Alternatively, the motor 60 can be bolted onto suitable motor mount in a motor casing with its controls preferably on the distal end portion of the handle 20 . (not shown)
Turning now to FIGS. 2-4 , it can be seen that rearwardly extending mounting brackets 57 are provided with an aperture disposed proximate the lower end of the trailing edge of the mounting bracket 57 . The mounting brackets 57 are positioned in spaced apart relationship and the proximal end portion 26 of the handle 20 is inserted between the two mounting brackets 57 . The mounting brackets 57 are secured to the proximal end portion 26 of the handle 20 by means of latch pins 58 , each extending through respective holes 59 . A plurality of holes 59 on each mounting bracket 57 permits adjustment of the vertical angular orientation of the handle 20 . The mounting brackets 57 include a plurality of aligned holes 59 which allow the operator to adjust angular relationship between the handle 20 and the mount member 54 . In one embodiment, the shingle removing apparatus 10 includes an optional wheel unit 53 positioned adjacent the proximal end portion 26 of the handle 20 . The wheel unit 53 can include a pair of wheels 53 mounted on an axle which extends through the apertures in the mounting bracket 57 for moving the apparatus 10 about a roof surface. The rearwardly tapered mount member 54 is attached to the mounting bracket 57 . In another embodiment, the mount member 54 can be directly connected to the handle 20 . The stripper member 50 is pivotally connected to the mount member 54 by means of outer and inner hinge sockets 55 respectively, mounted on a hinge pin 56 .
The stripper member 50 is driven by the motor 60 mounted to the handle 20 . The drive assembly 80 comprises the motor 60 operatively connected to the drive shaft 25 that can be enclosed by a tubular housing portion 22 of the handle 20 and which extends from the motor 60 to a worm gear 32 , as illustrated in FIG. 5 . The lower end of the drive shaft 25 connected to a gear assembly 30 including a ring gear 34 and worm gear 32 . Preferably, at least the lower portion of the drive shaft 25 is flexible to accommodate the angular adjustment between the handle 20 and the mount member 54 , for convenience of construction, the drive shaft 25 can be a flexible drive cable. The drive shaft 25 is operatively coupled to the worm gear 32 in a conventional manner as illustrated in FIG. 5 . The worm gear 32 is suitably mounted in a housing 31 and is operatively engaged with a ring gear 34 . The motor 60 is actuated by means of the trigger 62 . Preferably the motor 60 is a variable speed motor with speed being selected by the trigger 62 . In a preferred embodiment the motor 60 is a variable speed drill motor with a chuck coupling the motor 60 to the drive shaft 25 .
The drive assembly 80 includes a gear assembly 30 for coupling the drive shaft 25 to drive linkage assembly 40 , 70 to effect reciprocative movement of the stripper member 50 . The shingle removing apparatus 10 of the present invention includes a drive linkage assembly 40 that provides lost motion oscillating driving of the stripper member 50 . The motor 60 drives the drive shaft 25 to ultimately rotate a crank arm 42 as illustrated in FIGS. 4 and 7 . It will be understood that the driving mechanism used to translate rotational motion of the drive shaft 25 into rotating motion of the crank arm 42 is not critical, and any driving mechanism known in the art may be used to translate rotational rotation of the drive shaft 25 into rotating motion of the crank arm 42 or the crank arm 72 .
The present shingle removing apparatus 10 includes the drive linkage assembly 40 providing preferred lost motion mechanism as illustrated in FIGS. 2-4 . In one embodiment, the drive linkage assembly 40 includes the crank arm 42 , a first link 44 and a second link 48 . The crank arm 42 is positioned on the exterior of the housing 33 and is rotated by the drive assembly 80 . The crank arm 42 is adapted for moving the first link 44 which is pivotally connected to the crank arm 42 by means of a pivot pin 49 . The first link 44 includes an elongated slot 45 spaced apart from the pivotal connection of the crank arm 42 and the first link 44 . The second link 48 includes a follower 47 which is movably received in the elongate slot 45 to form a lost motion pivotal connection. The slot 45 receives the follower 47 for free movement of the follower 47 along the elongated slot 45 . The elongated slot 45 has a length sufficient to effect intermittent movement of the stripper member 50 during continuous rotation of the crank arm 42 . As a result, the lost motion mechanism delays movement of the stripper member 50 during a predetermined portion of the rotation of the crank arm 42 . In this regard, an operator can move the shingle removing apparatus 10 forward without manually stopping the motor due to effect a time delay in the movement of the stripper member to insert it under more shingles 1 . When the crank arm 42 is initially rotated by a gear assembly 30 , the stripper member 50 is permitted to rotate through a predetermined “lost motion” connection before establishing a direct-drive driving connection therewith to delay lifting or lowering the leading edge 51 of the stripper member 50 . Once the direct-drive driving connection is established, further rotation of the crank arm 42 will cause the stripper member 50 to lift or lower. This “lost motion” feature advantageously aids in going forward for removing next shingles. The operator can proceed rapidly and safely as slow return of the stripper member 50 to the set up position is accomplished by the lost motion mechanism. It is preferred that the drive assembly be constructed so that the direct drive portion of a crank arm rotation is preferably adjacent 3 o'clock and 9 o'clock portion of the crank arm 42 to provide mechanical advantage during the lifting movement of the stripper member 50 and less impact from the follower 47 following out at the each of the slot 45 .
An alternate embodiment of the shingle removing apparatus 10 of the present invention is shown in FIGS. 6 and 7 . The drive linkage assembly 70 includes a crank arm 72 and a link arm 76 . The crank arm 72 is pivotally connected to the gear assembly 30 and is rotated by the gear assembly 30 . The link arm 76 is pivotally coupled to the eccentric portion 71 of the crank arm 72 by means of a follower 79 . The link arm 76 has first end and second end portions, the second end portion being operatively engaged with a second link 77 , the first end portion being pivotally connected to the eccentric portion of the crank arm 72 . The second link is secured to the upper surface of the stripper member 50 . The link arm 76 includes an elongated slot 73 spaced apart from the pivotal connection of the link arm 76 to the second link 77 . The crank arm 72 includes the follower 79 which is mounted to and pivotally engaged with the elongated slot 73 through the lost motion connection. The elongated slot 73 receives the follower 79 for free movement of the follower 79 along the elongated slot 73 . The elongated slot 73 has a length sufficient to effect intermittent movement of the stripper member 50 during continuous rotation of the crank arm 72 . As a result, the lost motion mechanism delays movement of the stripper member 50 . The drive linkage assembly 70 further comprises two discs 78 which are positioned in spaced apart relationship with the lost motion connection between the discs to shield a pinch point.
In conclusion, the shingle removing machine greatly facilitates the removal of shingles from a roof. The time delay of the drive arm actuation oscillates and reciprocates the shingle removing blades in an efficient pattern.
Moreover, it will be understood that although the terms first, second and third are used herein to describe various features, elements, regions, layers and/or sections, these features, elements, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one feature, element, region, layer or section from another feature, element, region, layer or section. Thus, a first feature, element, region, layer or section discussed below could be termed a second feature, element, region, layer or section, without departing from the teachings of the present invention.
Thus, there has been shown and described several embodiments of a novel invention. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art.
Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow. The scope of the disclosure is not intended to be limited to the embodiments shown herein, but is to be accorded the full scope consistent with the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” All structural and functional equivalents to the elements of the various embodiments described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. | The present invention discloses a shingle removing apparatus which includes a handle, a stripper member, a drive assembly and a drive linkage assembly with lost motion mechanism. The stripper member is adapted for inserting under a shingle has a first end portion and a second end portion. The drive assembly drives at least a portion of the stripper member and the drive linkage assembly causes at least portion of the stripper member to reciprocally move up and down to thereby remove the shingle. The drive linkage assembly provides a lost motion mechanism which allows the stripper member to intermittently not be driven. | 4 |
CLAIM OF PRIORITY
[0001] The present application claims priority from Japanese application serial no. 2005-195243, filed on Jul. 4, 2005, the content of which is hereby incorporated by reference into this application.
FIELD OF THE INVENTION
[0002] The present invention relates to a fuel injection valve used for an internal combustion engine, especially, to a fuel injection valve using a magnetostrictive element as an actuator of the injection valve.
BACKGROUND OF THE INVENTION
[0003] Fuel injection valves used for internal combustion engines of using a magnetostrictive element as an actuator for the injection valve, have been suggested. For example, in a fuel injector disclosed in Japanese Patent Application Laid-Open JP-A No. 2001-234830, a pilot valve is used as the actuator, and a magnetostrictive element is used for controlling pressure oil of driving the valve rod. In this related technique, the following structure has been suggested. The magnetostrictive element comprises plural magnetostrictive rods (a first magnetostrictive rod and a second magnetostrictive rod). The magnetostrictive rods are arranged in parallel to each other (tandem arrangement), and coupled to each other via a coupling member. A fuel injection nozzle disclosed in this prior art controls an injection rate pattern variably in a wide range from the low injection pressure to high injection pressure. The magnetostrictive element is disposed in parallel to an axis of the pilot valve. A lift amount of the pilot valve is determined by the sum of extension (deformation) amounts of the first and second magnetostrictive rods, so that the lift amount can be increased.
[0004] In Japanese Patent Application Laid-Open JP-A No. is 2000-262076, a super magnetostrictive actuator is used as a driving device of a fuel injection valve. This actuator uses at least two super magnetostrictive members in combination with each other. In this fuel injection valve, a first and second magnetostrictive members disposed coaxially are coupled to each other via a coupling member. Both magnetostrictive members are coupled to each other to generate an extension corresponding to the sum of extension amounts of both magnetostrictive members when a magnetic field is produced. The lift amount of the valve rod is determined by this extension.
[0005] In a fuel injection valve operated high-responsively by use of a magnetostrictive element, a wide range of a flow rate (maximum flow rate, minimum flow rate) needs to be controlled accurately. Therefore, it is very important to determine a lift amount of an injection nozzle valve rod of the fuel injection valve, to increase the lift amount, and to decrease variations of the lift amount.
[0006] The fuel injection valve with the magnetostrictive element as the actuator has the following unevennesses per product: unevenness of magnetostrictive amount, unevenness of positional adjustment between the valve rod and magnetostrictive element, and unevenness due to the thermal expansion with variations in temperature. The lift amount of the valve rod varies due to such evennesses, so that unevenesses of the flow rates of the fuel injection valves are responsible very large.
[0007] Recently, as an engine aiming for high fuel-efficiency and high power, in-cylinder direct injection type gasoline engines (hereinafter called direct injection engines) are in practical use. As the direct injection engine, there are an engine having a fuel injection valve disposed to a side surface of a combustion chamber of the engine as shown in FIG. 7A , an engine having a fuel injection valve disposed just above a combustion chamber of the engine as shown in FIG. 7B , and the like. In the direct injection engines shown in FIGS. 7A and 7B , a suitable form of fuel injection and an optimum flow rate are required in accordance with the combustion method, a shape of the combustion chamber, a scale of the combustion chamber, and the like.
[0008] On the other hand, in the direct injection engine, the time from the fuel injection to the ignition is short, and the time until the fuel injected to the inside of the cylinder is vaporized is short. Therefore, to encourage the vaporization of fuel, the fuel needs to be atomized. The form of the fuel injection, the atomization of fuel, and the optimum flow rate influence concerning an amount of unburned-fuel components in the engine exhaust (hereinafter called HC), an amount of nitrogen oxides (hereinafter called NO x ), and fuel efficiency.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a fuel injection valve using a magnetostrictive element, in which an optimum fuel flow rate can be obtained by opening and closing an injection nozzle orifice more accurately.
[0010] The fuel injection valve of the present invention is basically structured as follows.
[0011] The fuel injection valve comprises: a fuel nozzle orifice; a valve seat provided upstream from the fuel nozzle orifice; a first valve rod for opening and closing the fuel nozzle orifice with axial movements relative to the valve seat; a spring for exerting the first valve rod away from the valve seat; the stopper for restricting a lift amount of the first valve rod lifted with a force of said spring; a solenoid for producing a magnetic field; a magnetostrictive element of extending when current passes through the solenoid and of shrinking when no current passes through the solenoid, and having a hysteresis in an axial deformation amount on extending and in an axial deformation amount on shrinking; and a second valve rod for pressing the first valve rod onto the valve seat against the force of the spring when the solenoid is not is energized, and for allowing the first valve rod to move away from the valve-seat with exertions of an extension of the magnetostrictive element and the force of the spring when the solenoid is energized. The extension amount of the magnetostrictive element when the first valve rod is fully open is set greater than a full stroke of the first valve rod from the valve seat to the stopper.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross sectional view showing a structure of a first embodiment of a fuel injection valve of the present invention;
[0013] FIGS. 2-3 are partial enlarged view of FIG. 1 ;
[0014] FIG. 4 is a graph showing a hysteresis characteristic of the fuel injection valve shown in FIG. 1 ;
[0015] FIG. 5 is a chart of a hysteresis characteristic of the fuel injection valve shown in FIG. 2 ;
[0016] FIG. 6 is a graph showing a hysteresis characteristic of the fuel injection valve of a second embodiment of the fuel injection valve of the present invention;
[0017] FIG. 7 is a chart of the hysteresis characteristic of the fuel injection valve shown in FIG. 4 ;
[0018] FIG. 8 is a cross sectional view showing a structure of a third embodiment of the fuel injection valve of the present invention; and
[0019] FIGS. 9A, 9B are diagrams showing examples in which the fuel injection valve is mounted to a cylinder fuel injection internal combustion engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiment 1
[0020] FIG. 1 is a cross sectional view of a first embodiment of a fuel injection valve 100 of the present invention. FIGS. 2-3 are partial enlarged view of FIG. 1 . Here, a nozzle 1 -side is called as a lower side, and a core 19 -side is called as an upper side.
[0021] In FIGS. 1-3 , a first valve rod 2 for opening and closing a fuel injection opening (orifice) is axially slidably inserted into the nozzle 1 . The nozzle 1 has a cylindrical shape. The first valve rod 2 has a rod shape. An orifice plate 3 is provided at the lower end portion of the nozzle 1 . One end of the first valve rod 2 is set into a tapered hole of the orifice plate 3 , the hole being upstream of the injection opening. A spring 4 is provided at the upper portion of the nozzle 1 . The spring 4 always presses the first valve rod 2 upward (valve opening direction). The upper portion of the nozzle 1 is set in a housing 5 and supported by the housing 5 . A stopper 6 is provided above the first valve rod 2 . When the first valve rod 2 is lifted by a predetermined amount, a flange portion provided at the first valve rod 2 comes into contact with the stopper 6 to regulate a lift amount of the first valve rod 2 . The stopper 6 is fixed by a base 7 attached to the upper end portion of the housing 5 . The stopper 6 has a donut shape.
[0022] More specifically, around the nozzle, a body of the fuel injection valve 100 is an assembly comprising the nozzle 1 , the housing 5 , a first yoke 11 , a second yoke 12 , an upper core 19 , and the like. The nozzle 1 comprises a valve guide 1 a having an elongated cylindrical shape and an upper cylindrical portion 1 b having a greater diameter than that of the valve guide 1 a. The cylindrical portion 1 b is inserted into the lower end inner circumference of the housing 5 , and secured by, for example, welding.
[0023] Inside the nozzle 1 and housing 5 coupled to each other as described above, the first valve rod 2 for opening and closing a fuel injection opening 32 , the spring 4 , the stopper 6 , and a spring bearing 40 are installed. An orifice 32 to be the fuel injection hole is provided at a center of the orifice plate 3 placed at the lower end portion of the nozzle 1 . A tapered hole 31 with a valve seat is provided upstream of the orifice 32 .
[0024] The first valve rod 2 is located between the orifice plate 3 and stopper 6 through the spring bearing 40 . A flange 20 is provided at the upper portion of the first valve rod 2 . The spring 4 is interposed between the flange 20 and spring bearing 40 .
[0025] An end (lower end) of the first valve rod 2 can come into contact with and come off from the seat on the tapered hole 31 of the orifice plate 3 when the first valve rod 2 axially reciprocates. Accordingly, the nozzle can be opened and closed. The spring 4 is placed from the upper portion of the nozzle 1 to the inside of the housing 5 . The spring 4 always provides the first valve rod 2 with spring force for pressing the first valve rod 2 in the upward direction in FIG. 1 (valve opening direction: away from the seat of the orifice plate 3 ). The upper cylindrical portion 1 b of the nozzle 1 is inserted into the housing 5 , and supported by the housing 5 . The stopper 6 for regulating a lift amount of the first valve rod 2 is fixed by the base 7 attached to the upper end portion of the housing 5 . The base 7 is secured to the upper end of the housing 5 by, for example, welding. The base 7 and stopper 6 have a donut shape. One end (lower end) of an after-mentioned second valve rod 8 is in contact with a head portion of the first valve rod 2 through the center hole portions of the base 7 and stopper 6 . The hole portion of the base 7 serves as a guide hole for guiding axial movement of the second valve rod 8 .
[0026] The upper portion of the housing 5 is coupled to the lower end portion of the cylindrical first yoke 11 . The upper portion of the yoke 11 is coupled to the lower end portion of the second yoke 12 . The second valve rod 8 is located at the center of the yoke 11 . The end of the second valve rod 8 is in contact with the upper end of the first valve rod 2 , and the first valve rod 2 and second valve rod 8 are disposed on the same axial line of them. A guide pipe 25 for guiding axial movement of the second valve rod 8 is placed to the outer circumference of the second valve rod 8 . The guide pipe 25 is supported by the base 7 . The guide pipe 25 is formed of a non-magnetic member. Outside the guide pipe 25 , a cylindrical magnetostrictive element 9 such as a super magnetostrictive is disposed. Outside the magnetostrictive element 9 , a cylindrical non-magnetic protection case 26 for protecting the magnetostrictive element 9 is disposed. An electromagnetic coil 10 for applying a magnetic field to the magnetostrictive element 9 is disposed outside the magnetostrictive element 9 . The yoke 11 is disposed outside the coil 10 .
[0027] Namely, the second valve rod 8 , guide pipe 25 , magnetostrictive element 9 , protection pipe 26 , coil 10 , and yoke 11 are disposed concentrically.
[0028] The magnetostrictive element extends and contracts under the influence of an external magnetic field, and has a positive magnetostrictive characteristic of extending in proportional to the magnetic field. For example, the magnetostrictive element is formed of ferroalloy including terbium (Tb) and dysprosium (Dy), which are rare earth elements. This magnetostrictive material extends and shrinks in extremely rapid response to a variation of the external magnetic field.
[0029] A cover 13 for covering the upper end of the magnetostrictive element 9 is provided on the upper end of the magnetostrictive element 9 . An element retaining member 14 for the magnetostrictive element is disposed on the cover 13 . A gap ring 15 for adjusting a gap is disposed on the element pressing member 14 . Namely, the element cover 13 , element retaining member 14 , and gap ring 15 are superimposed on the upper end of the magnetostrictive element 9 . A flange portion 27 a of the second valve rod 8 is located above the gap ring 15 . A spring 16 for providing preload to the magnetostrictive element 9 is provided above the element retaining member 14 . By providing axial preload to the magnetostrictive element, the magnetostrictive element has a characteristic showing a great magnetostrictive constant. A spring 17 is provided above the flange portion 27 a of the second valve rod 8 .
[0030] The upper end of the flange portion 27 a receives spring force of the spring 17 . By means of the spring 17 , the second valve rod 8 is always pressed in the valve closing direction (downward). The springs 16 , 17 are housed in the core 19 attached to the upper end portion of the yoke 12 . One end of the spring 16 is supported by a step portion (spring bearing portion) formed in the core 19 . The other end is supported by the upper surface of a flange portion 14 a of the element retaining member 14 . One end of the spring 17 is supported by an adjuster pin 18 provided to the core 19 . The other end is supported by an upper end flange 14 a of the second valve rod.
[0031] More specifically, an upper flange 27 a of the second valve rod 8 is formed in one piece with a cylindrical body 27 secured to the upper end of the valve rod 8 . The cylindrical body 27 has a fuel path in itself. Multiple fuel guide holes 28 guiding fuel to the outer circumference of the cylindrical body 27 , are arranged to a wall on the path. The most part of the cylindrical body 27 , other than the flange 27 a, is inserted into the inner circumference of the element retaining member 14 .
[0032] When no magnetic field is applied to the magnetostrictive element 9 , the second valve rod 8 receives spring force of the spring 17 to press the first valve rod 2 onto the seat (initial state). In this initial state, the valve is closed. A gap (for example, about 20 to 40 μm) for keeping a stroke range (lift range) of the first valve rod 2 is ensured between the upper end flange 20 and the stopper 6 . A gap (for example, about 5 μm) for absorbing axial thermal expansion of the magnetostrictive element 9 is provided between the upper flange 27 a and gap ring 15 . This thermal expansion absorbing gap is smaller than the gap for the lift of the valve.
[0033] An overall length of the second valve rod 8 is longer than that of the magnetostrictive element 9 . This is because the material of the magnetostrictive element 9 is different from that of the second valve rod 8 , and each linear expansion coefficient is different from each other. Namely, in general, a linear expansion coefficient of the magnetostrictive element 14 is greater than that of the second valve rod 8 . Even in such a situation, to keep the thermal expansion absorbing gap almost constant, it is necessary that a length of the second valve rod 8 is properly made longer than that of the magnetostrictive element 9 to almost match both expansions due to the thermal expansion to each other. A ratio between the lengths of both members is determined by each thermal expansion ratio and length, and by thermal expansion ratios and lengths of the related members such as the first valve rod 2 , cylindrical body 27 , and element pressing member 14 . For example, the magnetostrictive element 9 is made of ferroalloy containing Tb and Dy as described above, valve rods 2 and 8 is made of stainless(SUS420J). The stainless(SUS420J) has wear resistance and corrosion protection, and its linear expansion coefficient is comparatively close to that of the magnetostrictive. The length of the second valve rod 2 is 1.2 times as long as the magnetostrictive element.
[0034] In the fuel injection valve 100 structured as described above, a magnetic circuit including the housing 5 , base 7 , magnetostrictive element 9 , element cover 13 , element retaining member 14 , and yokes 11 , 12 is structured around the coil 10 .
[0035] In the fuel injection valve 100 structured as described above, when an injection pulse is “off”, and no current passes through the coil 10 , a force of the spring 4 exerts upward pressure on the first valve rod, and a force of the spring 17 exerts downward pressure on the second valve rod. As the force of the spring 17 is larger than that of the spring 4 , the upper surface of the flange portion of the first valve rod 2 is pressed by the second valve rod 8 , and valve rod 2 keeps in contact with the valve seat in a valve closing state. In this state, a gap corresponding to the lift amount of the first valve rod 2 is provided between the first valve rod 2 and stopper 6 .
[0036] When the injection pulse is “on”, the current passes through the coil 10 to form a magnetic field. Then, the magnetostrictive element 9 extends upward. An amount of extension of the magnetostrictive element 9 is greater than the thermal expansion absorbing gap. Therefore, when the second valve rod extends upward, the element cover 13 , element pressing member 14 , and gap ring 15 are pressed upward against exertion force of the springs 16 , 17 . At last, the gap ring 15 lifts the second valve rod 8 upward. Accordingly, the first valve rod 2 is lifted up by force of the spring 4 until the first valve rod 2 comes in contact with the stopper 6 . Then, the valve opens. The lift amount of the first valve rod 2 is regulated by the stopper 6 . The lift amount of the first valve rod 2 is set smaller than a extension amount of the magnetostrictive element 9 .
[0037] When the injection pulse becomes “off”, no current passes through the coil 10 , and the magnetostrictive element 9 returns to its original form with shrinking. By use of the spring force, the second valve rod 8 and first valve rod 2 return to the valve closed state. Then, the fuel injection is finished.
[0038] FIG. 4 shows the hysteresis characteristic of the magnetostrictive element 9 and the valve lift setting method of the stopper 6 . When a magnetostriction amount of the magnetostrictive element 9 changes, the second valve rod 8 is lifted upward or downward.
[0039] In FIG. 4 , the magnetostriction amount of the magnetostrictive element 9 is in proportion to a magnetic field intensity. On a magnetizing route side of a hysteresis, when the magnetic field intensity is increased from a zero point (ppm) to C (k0e), the magnetostriction amount increases from zero (ppm) to F (ppm). On the magnetizing route side of the hysteresis, when the magnetic field intensity is increased from C (k0e) to A (k0e), the magnetostriction amount increases from F (ppm) to E (ppm). When the magnetic field intensity is increased from A (k0e) to B (k0e), the magnetostriction amount increases from E (ppm) to D (ppm) as the maximum magnetostriction amount.
[0040] On the other hand, on a demagnetizing route side of the hysteresis, when the magnetic field intensity is decreased from B (k0e) of showing the maximum magnetostriction amount D to C (k0e) smaller than B(k0e), the magnetostriction amount decreases from D (ppm) to E (ppm). The magnetostriction amount E (ppm) corresponds to the magnetic field intensity A (A0e) on the magnetizing route side of the hysteresis. Therefore, even when the same magnetostriction E (ppm) is obtained, the magnetic field intensity applied on the magnetizing route side of the hysteresis is different from that on the demagnetizing route side of the hysteresis (A (k0e) on the magnetizing route side corresponds to C (k0e) on the demagnetizing route side).
[0041] Relationship between a current (A) to be applied to the coil 10 and the valve lift amount (μm) is the same as the relationship between the magnetostriction amount and the magnetic field intensity. On the magnetizing route side of the hysteresis, when a supplied current (A) is increased from zero (A) to I (A), the lift amount increases from zero (μm) to M (μm). On the magnetizing route side of the hysteresis, when the supplied current (A) is increased from I (A) to G (A), the lift amount increases from M (μm) to K (μm). When the supplied current (A) is increased from G (A) to H (A), the lift amount increases from K (μm) to J (μm) as the maximum lift amount.
[0042] On the other hand, on the demagnetizing route side of the hysteresis, when the supplied current (A) is decreased from H (A) showing the maximum lift amount J (μm) to the current I (A) smaller than the current H (A), the lift amount decreases from J (μm) as the maximum lift amount to K (μm). The lift amount K (μm) corresponds to the current G (A) on the magnetizing route side of the hysteresis. Therefore, when the same lift amount K (μm) is obtained, the supplied current (A) on the magnetizing route side of the hysteresis is different from that on the demagnetizing route side of the hysteresis (G (A) on the magnetizing route side corresponds to I (A) on the demagnetizing route side).
[0043] When the lift amount needs to be increased, the demagnetizing route side of the hysteresis of the magnetostrictive element 9 is preferably used to reduce the current (A) for obtaining the same lift amount. In the embodiment shown in FIG. 1 , when the current is I (A) on the hysteresis demagnetizing route side, the lift amount of the second valve rod 8 above the first valve rod 2 is K (μm). On the other hand, the lift amount of the first valve rod 2 is L (μm), the definition line by the stopper 6 , because the stopper 6 restricts the lift amount.
[0044] FIG. 5 is a characteristic graph of the state shown in FIG. 4 . In FIG. 5 , the horizontal axis shows a time (ms), and the vertical axis shows a voltage (V), a current (A), a magnetostriction amount (ppm), a lift amount of the second valve rod (μm), and a lift amount of the first valve rod (μm). Symbols in FIG. 5 correspond to the positions of the symbols shown in FIG. 4 , in consideration of the magnetizing route side and demagnetizing route sides of the hysteresis.
[0045] In FIG. 5 , as explained in FIG. 4 , even when the same lift amount K (μm) is obtained, the supplied current on the magnetizing route side of the hysteresis is different from that on the demagnetizing route side of the hysteresis. When the lift amount needs to be increased (from M (μm) to K (μm)), the demagnetizing route side of the hysteresis is preferably used. On the demagnetizing route side of the hysteresis, when the current is I (A), the lift amount of the second valve rod 8 above the first valve rod 2 is k (μm). On the other hand, since the stopper 6 restricts (defines) the lift amount of the first valve rod 2 , the lift amount is L (μm) to be the valve stroke restriction line (stopper position line) determined by the stopper 6 . Therefore, variations of the magnetostriction amount of the magnetostrictive element 9 itself, and variations of positional adjustment between the second valve rod 8 and magnetostrictive element 9 , can be reduced. Variation of a flow rate of the fuel injection valve 100 can be reduced. As a result, the injection amount can be controlled accurately in a wide range.
Embodiment 2
[0046] FIG. 6 shows a second embodiment of the hysteresis characteristic of the magnetostrictive element of the fuel injection valve 100 of the present invention, and of the valve stroke restriction method with the stopper.
[0047] In FIG. 6 , the magnetostriction amount of the magnetostrictive element 9 is in proportion to the magnetic field intensity, as well as in FIG. 2 . On the magnetizing route side of the hysteresis, when the magnetic field intensity is increased from zero (k0e) to C (k0e), the magnetostriction amount increases from zero (ppm) to F (ppm). On the magnetizing route side of the hysteresis, when the magnetic field intensity is increased from C (k0e) to A′ (k0e), the magnetostriction amount increases from F (ppm) to E′ (ppm). When the magnetic field intensity is increased from A′ (k0e) to A (k0e), the magnetostriction amount increases from E′ (ppm) to E (ppm). When the magnetic field intensity is increased from A (k0e) to B (k0e), the magnetostriction amount increases from E′ (ppm) to D (ppm) as the maximum magnetostriction amount.
[0048] On the other hand, on the demagnetizing route side of the hysteresis, when the magnetic field intensity is decreased from B (k0e) showing the maximum magnetostriction amount D (ppm) to C (k0e) smaller than the magnetic field intensity B (k0e), the magnetostriction amount decreases from D (ppm) to E (ppm). The magnetostriction amount E (ppm) corresponds to the magnetic field intensity A (k0e) on the magnetizing route side of the hysteresis. Therefore, when the same magnetostrictive amount E (ppm) is obtained, the magnetic field intensity on the magnetizing route side of the hysteresis is different from that on the demagnetizing route side of the hysteresis (A (k0e) on the magnetizing route side corresponds to C (k0e) on the demagnetizing route side). When the magnetic field intensity is decreased from C (k0e) to C′ (k0e) smaller than the magnetic field intensity C (k0e), the magnetostriction amount decreases from E (ppm) to E″ (ppm).
[0049] Relationship between the current (A) and lift amount (μm) is the same as the relationship between the magnetostriction amount and the magnetic field intensity. Namely, on the magnetizing route side of the hysteresis, when the supplied current (A) is increased from zero (A) to I (A), the lift amount increases from zero (μm) to M (μm). On the magnetizing route side of the hysteresis, when the supplied current (A) is increased from I (A) to G′ (A), the lift amount increases from M (μm) to L′ (μm). On the magnetizing route side of the hysteresis, when the supplied current (A) is increased from G′ (A) to G (A), the lift amount increases from L′ (μm) to K (μm). When the supplied current (A) is increased from G (A) to H (A), the lift amount increases from K (μm) to J (μm).
[0050] On the other hand, on the demagnetizing route side of the hysteresis, when the supplied current (A) is decreased from H (A) showing the maximum lift amount J (μm) to I (A) smaller than H (A), the lift amount decreases from J (μm) as the maximum lift amount to K (μm). The lift amount K (μm) corresponds to the current G (A) on the magnetizing route side of the hysteresis. Therefore, even when the same lift amount K (μm) is obtained, the supplied current (A) on the magnetizing route side of the hysteresis is different from that on the demagnetizing route side of the hysteresis (G (A) on the magnetizing route side, I (A) on the demagnetizing route side). When the supplied current (A) is decreased from I (A) to I′ (A), the lift amount decreases from K (μm) to L (μm).
[0051] In the embodiment shown in FIG. 1 , when the current is I (A) on the demagnetizing route side of the hysteresis., the lift amount of the second valve rod 8 above the first valve rod 2 is K (μm). The lift amount of the first valve rod 2 is L (μm), which is the valve stroke restriction line (stopper position line) with the stopper 6 , because the stopper 6 regulates the lift amount.
[0052] In this embodiment, the lifting action is controlled so as to be momentarily stopped at a position to just moments before reaching the lift amount L (μm) which is the valve stroke restriction line with the stopper 6 , on both the magnetizing and demagnetizing route sides of the hysteresis. The positions to be momentarily stopped are the lift amount L′ (μm) on the magnetizing route side and the lift K (μm) on the demagnetizing route side). On the magnetizing route side of the hysteresis, a speed of the first valve rod 2 is decreased just moments before the first valve rod 2 collides with the stopper 6 (the point of the lift amount L′ (μm)), so that the bound after the first valve rod 2 collides with the stopper 6 is effectively reduced. On the demagnetizing route side of the hysteresis, a speed of the second valve rod 8 is decreased just moments before the second valve rod 8 collides with the first valve rod 2 (a point of the lift K (μm)) when the second valve rod 8 operates on the valve closing side, so that the bound after the second valve rod 8 collides with the first valve rod 2 is effectively reduced.
[0053] FIG. 7 shows a characteristic graph of the state shown in FIG. 6 . In the characteristic graph, the horizontal axis shows a time (ms), and the vertical axis shows a voltage (V), current (A), magnetostriction amount (ppm), lift amount of the second valve rod (μm), and lift amount of the first valve rod (μm). The symbols in FIG. 7 correspond to the positions of the symbols shown in FIG. 6 , in consideration of the magnetizing route side and demagnetizing route side of the hysteresis.
[0054] In FIG. 7 , as shown in FIG. 6 , the lifting action is stopped momentarily just moments before the definition line (lift amount K (μm)) of the stopper 6 on the magnetizing and demagnetizing route sides of the hysteresis. The momentarily positions are a point of the lift amount L′ (μm) on the magnetizing route side of the hysteresis, and a point of the lift amount K (μm) on the demagnetizing route side of the hysteresis.
[0055] In this embodiment, the variations of the magnetostriction amount of the magnetostrictive element 9 itself and the variations of the positional adjustment between the second valve rod 8 and magnetostrictive element 9 are effectively reduced. In addition, on the magnetizing route side of the hysteresis, a speed of the first valve rod 2 is decreased just moments before the first valve rod 2 collides with the stopper 6 (a point of the lift amount L′ (μm)), so that the bound after the first valve rod 2 collides with the stopper 6 is effectively reduced. The bound after the first valve rod 2 collides with the stopper 6 can be reduced, so that the variation of a flow rate of the fuel injection valve 100 can be reduced. As a result, the injection amount can be controlled accurately in the wide range.
Embodiment 3
[0056] FIG. 8 shows a cross sectional view showing a third embodiment of the fuel injection valve 100 of the present invention. In FIG. 8 , reference symbols same as that of FIG. 1 show the same parts as parts of FIG. 1 .
[0057] In FIG. 8 , this embodiment is different from the embodiment shown in FIG. 1 in that the first valve rod 2 and second valve rod 8 moving to open and close the fuel injection opening of the orifice 30 shown in FIG. 1 are integrated into a single valve rod 30 . The valve rod 30 is provided penetrating the yokes 12 , 11 and injection nozzle 1 .
[0058] In FIG. 8 , the spring 4 used in FIG. 1 is omitted. When the current doesn't pass through the coil 10 , the valve rod 30 comes into contact with the valve seat of the orifice plate 3 by the spring 30 -force exertion. When the current passes through the coil 10 , the magnetostrictive element extends in an upward direction, and thereby the valve rod 30 is lifted away from the valve seat against the force of the spring 17 until a part of the rod comes into contact with the stopper. In this case, the rod 30 is provided so as to be allowed to pass through the annular base 7 , a step part 33 of the rod 30 may come into contact with the base 7 as the stopper.
[0059] In the other points, this embodiment is the same as the embodiment shown in FIG. 1 .
[0060] In such a structure, the bound generated from the collision between the second valve rod 8 and first valve rod 2 in the embodiment shown in FIG. 1 can be effectively reduced.
[0061] A piezo element may be used as the magnetostrictive element in the above-mentioned embodiments 1-3 in addition to the above mentioned super magnetostrictive element.
[0062] According to the present invention, an optimum fuel flow rate determined by opening and closing the an injection nozzle can be controlled accurately. | A valve seat is provided upstream from said fuel nozzle orifice. A first valve rod opens and closes the fuel nozzle orifice with axial movements relative to the valve seat. A spring exerts the first valve rod away from the valve seat. A stopper restricts a lift amount of the first valve rod lifted with a force of the spring. A solenoid produces a magnetic field. A magnetostrictive element extends when current passes through the solenoid and shrinks when no current passes through said solenoid, and having a hysteresis in an axial deformation amount on extending and in an axial deformation amount on shrinking. A second valve rod presses the first valve rod onto the valve seat against the force of the spring when the solenoid is not energized, and for allows the first valve rod to move away from the valve seat with exertions of an extension of the magnetostrictive element and the force of said spring when said solenoid is energized. Wherein the extension amount of the magnetostrictive element when the first valve rod is fully open is set greater than a full stroke of the first valve rod from the valve seat to the stopper. | 5 |
RELATED APPLICATIONS
[0001] This application is a divisional application of U.S. patent application Ser. No. 13/391,910, filed Mar. 9, 2012, which is a 35 U.S.C. §371 U.S. National Phase Entry of International Application No. PCT/US2010/046773 filed Aug. 26, 2010, which claims the benefit of U.S. provisional application Ser. No. 61/237,592, filed Aug. 27, 2009, the entirety of which is incorporated herein by reference.
REFERENCE TO SEQUENCES
[0002] The present application is being filed along with a Sequence Listing in electronic format. The Sequence Listing file, entitled 20151010USDIVSEQLST.txt, was created on Dec. 3, 2013 and is 1,600 bytes in size. The information in electronic format of the Sequence Listing is incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0003] The present invention relates to antibodies and related molecules that immunospecifically bind to fatty acid synthase and related pathway proteins, and their use in immunoassays for fatty acid synthase activity. The invention relates to methods and assays for detecting, screening, diagnosing or determining the progression of a proliferative disease or pre-cancerous condition using the present antibodies and assays.
BACKGROUND ART
[0004] Fatty acid synthase (FAS) is a 270 kDa cytosolic protein that functions as a homodimer. (1) FAS is expressed in low to undetectable levels in most normal human tissues. (2) In contrast, FAS is overexpressed in a large number of human cancers, including prostate cancer, despite high levels of ambient fatty acids, and its overexpression has been associated with poor prognosis. (3-6) In prostate cancer, FAS is overexpressed throughout the natural history of a majority of tumors beginning with prostatic intraepithelial neoplasia (PIN). (3) Although the biochemical and metabolic basis for FAS overexpression in tumor cells in not well understood, it appears that FAS overexpression confers a selective growth advantage to tumor cells. Prostate tumors expressing high FAS levels display aggressive biologic behavior. (7) (8)
[0005] Prostate-specific antigen (PSA) is used as a biological or tumor marker to detect prostate disease. PSA is a protein produced by cells of the prostate gland. The PSA test measures the level of PSA in the blood; but PSA alone is not a reliable indicator of the presence of prostate disease.
[0006] It is normal for men to have a low level of PSA in their blood. The reference range of PSA is between 0-4.0 ng/mL, based on a study that found 99% of a cohort of apparently healthy men had a total PSA level below 4 ng/mL; the upper limit of normal is much less than 4 ng/mL. (9)(10) Increased levels of PSA may suggest the presence of prostate cancer; however, prostate cancer can also be present in the complete absence of an elevated PSA level, in which case the test result would be a false negative. (9)
[0007] As men age, both benign prostate conditions and prostate cancer become more common, resulting in an increase in PSA levels. PSA levels can be increased by conditions including prostate infection, irritation or benign prostatic hyperplasia (BPH). (11)(12) According to the National Cancer Institute, PSA levels alone do not give doctors enough information to distinguish between benign prostate conditions and cancer. Treatment needs to be individualized based on the individual's risk of progression as well as the likelihood of success and the risks of the treatment. (13)
SUMMARY OF THE INVENTION
[0008] The invention comprises methods, compositions and kits for the rapid and accurate identification of fatty acid synthase (FAS) expression in patients having or suspected of having a proliferative disorder or pre-cancerous condition characterized by FAS overexpression. The present method comprises determining the level of expression of the FAS gene or protein in biological sample of a patient having or suspected of having prostate cancer, prostatic intraepithelial neoplasia (PIN), or another proliferative disorder or pre-cancerous condition using monoclonal or polyclonal antibodies that are highly specific for FAS.
[0009] The present method generally comprises the following steps: (a) obtaining a biological sample containing cancer cells from a patient; (b) contacting the sample with antibodies specific for FAS; (c) detecting the presence and amount of FAS conjugated with the antibodies; and (d) correlating the amount of FAS with the presence or aggressiveness of the cancer or pre-cancerous condition, the likelihood that the cancer will recur, and/or the likelihood that the cancer will respond to therapeutic treatment.
[0010] The assay of the present invention utilizes novel antibodies that are highly specific for human FAS. The antibodies may be polyclonal or monoclonal, and may be used as capture and/or detection antibodies in an immunoassay. In a currently preferred embodiment, the antibodies are monoclonal antibodies raised against FAS peptides derived from sections of human FAS protein having the least homology with non-human FAS.
[0011] Any type of immunoassay format may be employed, including enzyme-linked immunoassays (EIA, ELISA), Western blot, Dot blot, radioimmunoassay (RIA), agglutination, flow cytometry, or other formats. In a preferred embodiment, the present assay employs a sandwich-ELISA technique to measure the level of FAS in cells circulating in a bodily fluid, such as human serum or plasma. In this embodiment, the anti-FAS antibodies of the invention are used as capture antibodies.
[0012] The kit of the invention comprises, at a minimum, (a) a substrate having anti-FAS antibodies immobilized thereon; and (b) detection antibodies tagged with a detectable moiety. The kit may further comprise contain reagents, e.g., for cell lysis and/or washing.
[0013] The present invention can be used for monitoring of disease progression for proliferative disorders characterized by the overexpression of FAS, especially prostate cancer, and for predicting the efficacy of certain therapeutic agents for treating such disorders. The present method and assay provides a more sensitive and more accurate prognostic tool than PSA for monitoring prostate cancer, and may be used in place of or in conjunction with PSA tests to monitor prostate cancer. In one aspect, the present method and kit can be used to predict the efficacy of therapeutic approaches, such as androgen ablation.
BRIEF DESCRIPTION OF THE FIGURES
[0014] FIG. 1 is a graph showing the results of an ELISA assay using monoclonal antibodies of the present invention raised against the peptide of SEQ. ID NOs. 1 and 2 as the capture antibody. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs.
[0015] FIG. 2 is a graph showing the results of an ELISA assay using a monoclonal antibody of the present invention raised against the peptide of SEQ. ID NO. 4 as the capture antibody. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs.
[0016] FIG. 3 is a graph showing the results of an ELISA assay using a monoclonal antibody of the present invention raised against the peptide of SEQ. ID NO. 5 as the capture antibody. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs.
[0017] FIG. 4 is a graph showing the results of an ELISA assay using polyclonal antisera of the present invention raised against the peptide of SEQ. ID NO. 3 as the capture antibody. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The present invention comprises methods, compositions and kits for the rapid and accurate identification of FAS expression in cells. FAS is overexpressed in a number of proliferative disorders, including prostate cancer, and pre-cancerous conditions, such as PIN.
[0019] The present method generally comprises the following steps: (a) obtaining a biological sample containing cancer cells from a patient; (b) contacting the sample with antibodies specific for FAS; (c) detecting the presence and amount of FAS conjugated with the antibodies; and (d) correlating the amount of FAS with the presence of PIN, the aggressiveness of prostate cancer, the likelihood that the cancer will recur, and/or the likelihood that the cancer will respond to therapeutic treatment. The biological sample may be cells or tissue, and preferably is serum or plasma containing cells. However, the cells also may be obtained from tissue samples or cell cultures.
[0020] FAS from cancer cells can be detected in circulating cancer cells in a blood sample. In a preferred embodiment, the present invention provides a method of detecting the expression of FAS from cancer cells in a blood sample comprising removing the red blood cells from the blood sample thereby localizing the cancer cells in the blood serum, lysing the cancer cells in the serum, followed by performing on the serum containing the lysed cells an immunoassay capable of detecting FAS.
[0021] The present assays and methods are sensitive enough for quantifying the levels of FAS in circulating cancer cells in blood samples. The present invention provides methods for identifying those cancer patients who are likely to benefit from certain anticancer therapies (including, but not limited to, FAS-targeted therapies). A convenient, highly sensitive and rapid means to test blood samples to identify additional patients who would benefit from such therapies would be an important advance in the cancer treatment field. As indicated below, a rapid and highly sensitive immunological assay to detect FAS proteins in circulating cancer cells.
[0022] This invention is based on combining the high specificity of procedures used to isolate circulating cancer cells from blood with the high sensitivity of certain immunologically based assays. Circulating cancer cells preferably are first concentrated in the serum or plasma by treating the blood sample to remove red cells. One preferred method uses centrifugation to remove red cells, thereby isolating the circulating cancer cells in the blood serum or plasma. Another preferred method of enrichment of cancer cells consists of collecting a whole blood sample followed by the lysis of red blood cells. The currently preferred method comprises collecting a whole blood sample in a cell preparation tube (such as the BD VACUTAINER®CPT, Becton Dickinson) and obtaining by centrifugation a peripheral blood mononuclear fraction that contains enriched cancer cells.
[0023] The antibodies used in the present invention for detection or capture of FAS are novel anti-FAS antibodies that are highly specific for human FAS. In a preferred embodiment, the present antibodies are monoclonal antibodies specific for a human FAS sequence selected from SEQ ID NOs. 1-5. In a preferred embodiment, the present antibodies are used as capture antibodies in a sandwich ELISA assay.
Anti-FAS Antibodies
[0024] The assays of the present invention utilizes novel antibodies that are highly specific for human FAS. The antibodies may be polyclonal or monoclonal, and may be used as capture and/or detection antibodies in an immunoassay. In a currently preferred embodiment, the antibodies are monoclonal antibodies raised against FAS peptides derived from sections of human FAS protein having the least homology with non-human FAS.
[0025] The present antibodies comprise polyclonal or monoclonal antibodies, or antibody fragments, that immunospecifically bind to a FAS protein, fragment or a variant of FAS, as well as certain FAS related pathway proteins. In particular, the invention encompasses antibodies or fragments thereof that immunospecifically bind to a FAS protein comprising at least about six consecutive amino acids up to the full length of any of the polypeptides of SEQ ID NOs. 1-5.
[0026] The antibodies of the present invention also comprise non-human monoclonal antibodies (e.g., murine, rabbit or goat) and polyclonal antisera that bind to FAS or variants thereof comprising at least a portion of the sequence of a peptide of SEQ ID NO. 1-5. In preferred aspect, the antibodies are human or humanized monoclonal antibodies. The antibodies of the present invention further encompass fragments or variants of these antibodies (e.g., VH domains, VH CDRs, VL domains, or VL CDRs), that immunospecifically bind to FAS or variants thereof comprising at least a portion of the sequence of a peptide of SEQ ID NO. 1-5. The present antibodies or fragments thereof also may bind to certain FAS-related proteins that contain at least a portion of the sequence of a peptide of SEQ ID NO. 1-5.
[0027] The antibodies of the present invention can be produced by using well-established techniques for producing monoclonal and polyclonal antibodies, using the FAS peptides of SEQ ID NO. 1-5 as immunogens. In a preferred embodiment, the FAS peptide contains an amino acid sequence that is identical with or homologous to all or a portion containing at least about six consecutive amino acids of a sequence represented by any one of SEQ ID NOs. 1-5. A homologous sequence is at least about 70%, 75%, 80%, 85%, 90% or 95% identical to the peptide represented by any one of SEQ ID NOs. 1-5, wherein X represents any naturally occurring amino acid.
[0000]
FAS Peptides:
SEQ ID NO. 1
VAQGQWEPSGXAP
SEQ ID NO. 2
PSGPAPTNXGALE
SEQ ID NO. 3
TLEQQHXVAQGQW
SEQ ID NO. 4
EVDPGSAELQKVLQGD
SEQ ID NO. 5
ELSSKADEASELAC
[0028] FAS peptides can be synthesized by methods well known in the art. Synthetic methods that can be used include, for example, ribosomally-directed fermentation methods, as well as non-ribosomal strategies and chemical synthesis methods. Methods for making the peptides are described in co-pending PCT application no. PCT/US10/30545, filed Apr. 9, 2010, the entirety of which is hereby incorporated herein by reference.
[0029] As used herein, the term “antibody” refers to an immunoglobulin specifically immunoreactive to a given antigen (e.g., a FAS peptide of the invention). The term “antibody” as used herein is intended to include whole antibodies of any isotype (IgG, IgA, IgM, IgE, etc), and fragments thereof. An “antibody” of the invention also includes an antibody preparation, e.g., a serum (antiserum). Antibodies can be fragmented using conventional techniques and the fragments screened for utility in the same manner as whole antibodies. Thus, the term includes segments of proteolytically-cleaved or recombinantly-prepared portions of an antibody molecule that selectively reacts with a certain protein or peptide. Non-limiting examples of such proteolytic and/or recombinant fragments include Fab, F(ab′)2, Fab′, Fv, and single chain antibodies (scFv) containing a V[L] and/or V[H] domain joined by a peptide linker. The scFv's may be covalently or non-covalently linked to form antibodies having two or more binding sites. Antibodies may be labeled with detectable labels by one of skill in the art. The label can be a radioisotope, fluorescent compound, chemiluminescent compound, enzyme, or enzyme co-factor, or any other labels known in the art. In some aspects, the antibody that binds to an entity one wishes to measure (the primary antibody) is not labeled, but is instead detected by binding of a labeled secondary antibody that specifically binds to the primary antibody.
[0030] Antibodies of the invention include, but are not limited to, polyclonal, monoclonal, multispecific, human, humanized or chimeric antibodies, single chain antibodies, Fab fragments, F(ab′) fragments, fragments produced by a Fab expression library, anti-idiotypic (anti-Id) antibodies (including, e.g., anti-Id antibodies to antibodies of the invention), intracellularly made antibodies (i.e., intrabodies), and epitope-binding fragments of any of the above. The antibodies of the invention can be from any animal origin including birds and mammals. Preferably, the antibodies are of human, murine (e.g., mouse and rat), donkey, sheep, rabbit, goat, guinea pig, camel, horse, or chicken origin.
[0031] As used herein, a “monoclonal antibody” refers to an antibody that recognizes only one type of antigen. This type of antibodies is produced by the daughter cells of a single antibody-producing hybridoma. A monoclonal antibody typically displays a single binding affinity for any epitope with which it immunoreacts. A monoclonal antibody may contain an antibody molecule having a plurality of antibody combining sites, each immunospecific for a different epitope, e.g., a bispecific monoclonal antibody. Monoclonal antibodies may be obtained by methods known to those skilled in the art. Kohler and Milstein (1975), Nature, 256:495-497; U.S. Pat. No. 4,376,110; Ausubel et al. (1987, 1992), eds., Current Protocols in Molecular Biology, Greene Publishing Assoc. and Wiley Interscience, N.Y.; Harlow and Lane (1988), Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory; Colligan et al. (1992, 1993), eds., Current Protocols in Immunology, Greene Publishing Assoc. and Wiley Interscience, N.Y.; Iyer et al., Ind. J. Med. Res., (2000), 123:561-564.
[0032] The antibodies of the present invention can be monospecific or multispecific (e.g., bispecific, trispecific, or of greater multispecificity). Multispecific antibodies can be specific for different epitopes of a peptide of the present invention, or can be specific for both a peptide of the present invention, and a heterologous epitope, such as a heterologous peptide or solid support material. See, e.g., WO 93/17715; WO 92/08802; WO 91/00360; WO 92/05793; Tutt et al., 1991 , J. Immunol., 147:60-69; U.S. Pat. Nos. 4,474,893; 4,714,681; 4,925,648; 5,573,920; 5,601,819; and Kostelny et al., 1992 , J. Immunol., 148:1547-1553. For example, the antibodies may be produced against a peptide containing repeated units of a FAS peptide sequence of the invention, or they may be produced against a peptide containing two or more FAS peptide sequences of the invention, or the combination thereof.
[0033] Moreover, antibodies can also be prepared from any region of the FAS peptides of the invention. In addition, if a polypeptide is a receptor protein, antibodies can be developed against an entire receptor or portions of the receptor, for example, an intracellular domain, an extracellular domain, the entire transmembrane domain, specific transmembrane segments, any of the intracellular or extracellular loops, or any portions of these regions. Antibodies can also be developed against specific functional sites, such as the site of ligand binding, or sites that are glycosylated, phosphorylated, myristylated, or amidated, for example.
[0034] In the present invention, the FAS peptides for generating antibodies preferably contain a sequence of at least about 6, at least about 7, more preferably at least about 8, at least about 9, at least about 10, at least about 11, at least about 12, at least about 13, and preferably, between about 5 to about 50 amino acids in length, more preferably between about 8 to about 15 amino acids in length. The preferred FAS peptides are those having an amino acid sequence the same as or homologous to all or a portion of the sequence of the peptides of SEQ ID NOs. 1-5.
[0035] The human, humanized or non-human monoclonal antibodies of the present invention can be prepared using well-established methods. In one embodiment, the monoclonal antibodies are prepared using hybridoma technology, such as those described by Kohler and Milstein (1975), Nature, 256:495. In a hybridoma method, a mouse, hamster, or other appropriate host animal, is typically immunized with an immunizing agent (e.g., a FAS peptide of the invention) to elicit lymphocytes that produce or are capable of producing antibodies that will specifically bind to the immunizing agent. Alternatively, the lymphocytes may be immunized in vitro. The lymphocytes are then fused with an immortalized cell line using a suitable fusing agent, such as polyethylene glycol, to form a hybridoma cell. Goding, Monoclonal Antibodies: Principles and Practice, Academic Press, (1986) pp. 59-1031 Immortalized cell lines are usually transformed mammalian cells, particularly myeloma cells of rodent, rabbit, bovine and human origin. Usually, rat or mouse myeloma cell lines are employed. The hybridoma cells may be cultured in a suitable culture medium that preferably contains one or more substances that inhibit the growth or survival of the unfused, immortalized cells. For example, if the parental cells lack the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT or HPRT), the culture medium for the hybridomas typically will include hypoxanthine, aminopterin, and thymidine (“HAT medium”), which substances prevent the growth of HGPRT-deficient cells. Preferred immortalized cell lines are those that fuse efficiently, support stable high level expression of antibody by the selected antibody-producing cells, and are sensitive to a medium such as HAT medium. More preferred immortalized cell lines are murine myeloma lines, which can be obtained, for instance, from the Salk Institute Cell Distribution Center, San Diego, Calif. and the American Type Culture Collection, Manassas, Va. Human myeloma and mouse-human heteromyeloma cell lines also have been described for the production of human monoclonal antibodies. Kozbor, J. Immunol. (1984), 133:3001; Brodeur et al., Monoclonal Antibody Production Techniques and Applications, Marcel Dekker, Inc., New York, (1987) pp. 51-63; Fukuma et al., Autoimmunity, 10(4):291-195 (1991).
[0036] The culture medium in which the hybridoma cells are cultured can then be assayed for the presence of monoclonal antibodies. Preferably, the binding specificity (i.e., specific immunoreactivity) of monoclonal antibodies produced by the hybridoma cells is determined by immunoprecipitation or by an in vitro binding assay, such as radioimmunoassay (RIA) or enzyme-linked immunosorbent assay (ELISA). Such techniques and assays are known in the art. The binding specificity of the monoclonal antibody can, for example, be determined by the Scatchard analysis of Munson and Pollard (1980), Anal. Biochem., 107:220.
[0037] After the desired hybridoma cells are identified, the clones may be subcloned by limiting dilution procedures and grown by standard methods (Goding, supra). Suitable culture media for this purpose include, for example, Dulbecco's Modified Eagle's Medium or RPMI-1640 medium. Alternatively, the hybridoma cells may be grown in vivo as ascites in a mammal
[0038] The monoclonal antibodies secreted by the subclones may be isolated or purified from the culture medium or ascites fluid by conventional immunoglobulin purification procedures such as, for example, protein A-Sepharose, hydroxylapatite chromatography, gel electrophoresis, dialysis, or affinity chromatography.
[0039] The monoclonal antibodies can also be made by recombinant DNA methods, such as those described in U.S. Pat. No. 4,816,567, which is hereby incorporated by reference in its entirety. DNA encoding the monoclonal antibodies of the invention can be readily isolated and sequenced using conventional procedures (e.g., by using olignucleotide probes that are capable of binding specifically to genes encoding the heavy and light chains of murine antibodies). The hybridoma cells of the invention serve as a preferred source of such DNA. Once isolated, the DNA can be placed into expression vectors, which are then transfected into host cells such as simian COS cells, Chinese hamster ovary (CHO) cells, or myeloma cells that do not otherwise produce immunoglobulin protein, to obtain the synthesis of monoclonal antibodies in the recombinant host cells. The DNA also can be modified, for example, by substituting the coding sequence for human heavy and light chain constant domains in place of the homologous murine sequences (see, U.S. Pat. No. 4,816,567) or by covalently joining to the immunoglobulin coding sequence all or part of the coding sequence for a non-immunoglobulin polypeptide. Such a non-immunoglobulin polypeptide can be substituted for the constant domains of an antibody of the invention, or can be substituted for the variable domains of one antigen-combining site of an antibody of the invention to create a chimeric bivalent antibody.
[0040] Polyclonal antibodies of the invention can also be produced by various procedures well known in the art. For the production of polyclonal antibodies in vivo, host animals, such as rabbits, rats, mice, sheep, or goats, are immunized with either free or carrier-coupled peptides, for example, by intraperitoneal and/or intradermal injection. Injection material is typically an emulsion containing about 100 μg of peptide or carrier protein. Various adjuvants can also be used to increase the immunological response, depending on the host species. Adjuvants include, but are not limited to, Freund's (complete and incomplete), mineral gels such as aluminum hydroxide, surface active substances such as lysolecithin, pluronic polyols, polyanions, peptides, oil emulsions, keyhole limpet hemocyanins, dinitrophenol, and potentially useful human adjuvants such as BCG (bacille Calmette-Guerin) and corynebacterium parvum . Such adjuvants are also well known in the art. Several booster injections may be needed, for instance, at intervals of about two weeks, to provide a useful titer of antibody which can be detected, for example, by ELISA assay using free peptide adsorbed to a solid surface. The titer of antibodies in serum from an immunized animal can be increased by selection of antibodies, e.g., by adsorption of the peptide onto a solid support and elution of the selected antibodies according to methods well known in the art.
[0041] Antibodies encompassed by the present invention can also be generated using various phage display methods known in the art. In phage display methods, functional antibody domains are displayed on the surface of phage particles which carry the polynucleotide sequences encoding them. In a particular embodiment, such phage can be utilized to display antigen binding domains expressed from a repertoire or combinatorial antibody library (e.g., human or murine). Phage expressing an antigen binding domain that binds to the antigen of interest can be selected or identified with antigen, e.g., using labeled antigen or antigen bound or captured onto a solid surface or bead. Phage used in these methods are typically filamentous phage including fd and M13 binding domains expressed from phage with Fab, Fv, or disulfide stabilized antibody domains recombinantly fused to either the phage polynucleotide III or polynucleotide VIII protein. Examples of phage display methods that can be used to make the antibodies of the present invention include those disclosed in Brinkman et al. (1995) J. Immunol. Methods, 182:41-50; Ames et al. (1995) J. Immunol. Methods, 184:177-186; Kettleborough et al. (1994) Eur. J. Immunol., 24:952-958; Persic et al. (1997) Gene, 187:9-18; Burton et al. (1994) Advances in Immunology, 57:191-280; PCT application No. PCT/GB91/01134; PCT publications WO 90/02809; WO 91/10737; WO 92/01047; WO 92/18619; WO 93/11236; WO 95/15982; WO 95/20401; and U.S. Pat. Nos. 5,698,426; 5,223,409; 5,403,484; 5,580,717; 5,427,908; 5,750,753; 5,821,047; 5,571,698; 5,427,908; 5,516,637; 5,780,225; 5,658,727; 5,733,743 and 5,969,108, each of which is incorporated herein by reference in its entirety.
[0042] As described in the above references, after phage selection, the antibody coding regions from the phage can be isolated and used to generate whole antibodies, including human antibodies, or any other desired antigen binding fragment, and expressed in any desired host, including mammalian cells, insect cells, plant cells, yeast, and bacteria, e.g., as described in detail below.
[0043] Examples of techniques that can be used to produce antibody fragments such as single-chain Fvs and antibodies include those described in U.S. Pat. Nos. 4,946,778 and 5,258, 498; Huston et al. (1991) Methods in Enzymology, 203:46-88; Shu et al. (1993) Proc. Natl. Acad. Sci. USA, 90:7995-7999; and Skerra et al. (1988) Science, 240:1038-1040, each of which is incorporated herein by reference in its entirety.
[0044] For some uses, including the in vivo use of antibodies in humans and in vitro detection assays, it is preferable to use chimeric, humanized, or human antibodies. A chimeric antibody is a molecule in which different portions of the antibody are derived from different animal species, such as antibodies having a variable region derived from a murine monoclonal immunoglobulin and a human immunoglobulin constant region. Methods for producing chimeric antibodies are known in the art. See, e.g., Morrison (1985), Science, 229:1202; Oi et al. (1986), BioTechniques, 4:214; Gillies et al. (1989), J. Immunol. Methods, 125:191-202; and U.S. Pat. Nos. 5,807,715; 4,816,567; and 4,816,397, which are incorporated herein by reference in their entirety.
[0045] Humanized antibodies are antibody molecules from non-human species that bind to the desired antigen and have one or more complementarity determining regions (CDRs) from the nonhuman species and framework regions from a human immunoglobulin molecule. Often, framework residues in the human framework regions are substituted with corresponding residues from the CDR and framework regions of the donor antibody to alter, preferably improve, antigen binding. These framework substitutions are identified by methods well known in the art, e.g., by modeling of the interactions of the CDR and framework residues to identify framework residues important for antigen binding, and by sequence comparison to identify unusual framework residues at particular positions. See, e.g., Queen et al., U.S. Pat. Nos. 5,693,762 and 5,585,089; and Riechmann et al. (1988) Nature, 332:323, which are incorporated herein by reference in their entireties. Antibodies can be humanized using a variety of techniques known in the art, including, for example, CDR-grafting (EP 239, 400; PCT publication WO 91/09967; U.S. Pat. Nos. 5,225,539; 5,530,101; and 5,585,089); veneering or resurfacing (EP 592,106; EP 519,596; Padlan (1991), Molecular Immunology, 28(4/5):489-498; Studnicka et al. (1994) Protein Engineering, 7(6):805-814; Roguska et al. (1994) Proc. Natl. Acad. Sci. USA, 91:969-973; and chain shuffling (U.S. Pat. No. 5,565,332). A currently preferred method for making humanized monoclonal antibodies of the present invention are the methods described by Le et al., Cell Cycle, 4(1):87-95 (2005) and Carter et al., Proc. Natl. Acad. Sci. USA, 89:4285-89 (1992), which are incorporated herein by reference.
[0046] Human antibodies can also be produced using transgenic mice which are incapable of expressing functional endogenous immunoglobulins, but which can express human immunoglobulin polynucleotides. For example, the human heavy and light chain immunoglobulin polynucleotide complexes can be introduced randomly, or by homologous recombination, into mouse embryonic stem cells. Alternatively, the human variable region, constant region, and diversity region may be introduced into mouse embryonic stem cells, in addition to the human heavy and light chain polynucleotides. The mouse heavy and light chain immunoglobulin polynucleotides can be rendered nonfunctional separately or simultaneously with the introduction of human immunoglobulin loci by homologous recombination. In particular, homozygous deletion of the JH region prevents endogenous antibody production. The modified embryonic stem cells are expanded and microinjected into blastocysts to produce chimeric mice. The chimeric mice are then bred to produce homozygous offspring which express human antibodies. The transgenic mice are immunized in the normal fashion with a selected antigen, e.g., all or a portion of a polypeptide of the invention.
[0047] Thus, using such a technique, it is possible to produce useful human IgG, IgA, IgM, IgD and IgE antibodies. For an overview of the technology for producing human antibodies, see Lonberg and Huszar (1995) Intl. Rev. Immunol., 13:65-93. For a detailed discussion of the technology for producing human antibodies and human monoclonal antibodies and protocols for producing such antibodies, see, e.g., PCT publications WO 98/24893; WO 92/01047; WO 96/34096; WO 96/33735; European Patent No. 0598 877; U.S. Pat. Nos. 5,413,923; 5,625,126; 5,633,425; 5,569,825; 5,661,016; 5,545,806; 5,814,318; 5,885,793; 5,916,771; 5,939,598; 6,075,181; and 6,114,598, which are incorporated by reference herein in their entirety. In addition, companies such as Abgenix, Inc. (Fremont, Calif.), Protein Design Labs, Inc. (Mountain View, Calif.) and Genpharm (San Jose, Calif.) can be engaged to provide human antibodies directed against a selected antigen using technology similar to the above described technologies. Preferred methods for producing human monoclonal antibodies of the present invention are those described in Nash et al., Immunology, 68:332-340 (1989) and Fukuma et al., Autoimmunity, 10(4):291-195 (1991).
[0048] Once an antibody molecule of the invention has been produced by an animal, a cell line, chemically synthesized, or recombinantly expressed, it can be purified (i.e., isolated) by any method known in the art for the purification of an immunoglobulin or polypeptide molecule, for example, by chromatography (e.g., ion exchange, affinity, particularly by affinity for the specific antigen, Protein A, and sizing column chromatography), centrifugation, differential solubility, or by any other standard technique for the purification of proteins. In addition, the antibodies of the present invention or fragments thereof can be fused to heterologous polypeptide sequences described herein or otherwise known in the art, to facilitate purification.
[0049] In one embodiment, the present invention provides human or humanized monoclonal antibodies that specifically immuoreact to a FAS protein, or fragment or variant thereof. In a preferred embodiment, the invention provides a novel monoclonal antibody that specifically recognizes a sequence comprising at least about 6 up to the entire sequence of a peptide selected from the group consisting of SEQ ID NOs. 1-5.
Assays
[0050] The term “immunoassay” refers to a test that uses the binding of antibodies to antigens to identify and measure certain substances. Immunoassays often are used to diagnose disease, and test results can provide information about a disease that may help in planning treatment (for example, when estrogen receptors are measured in breast cancer). An immunoassay takes advantage of the specific binding of an antibody to its antigen. Monoclonal antibodies are often used as they usually bind only to one site of a particular molecule, and therefore provide a more specific and accurate test, which is less easily confused by the presence of other molecules. The antibodies used must have a high affinity for the antigen of interest, because a very high proportion of the antigen must bind to the antibody in order to ensure that the assay has adequate sensitivity.
[0051] The immunoassays of the present invention utilize the ant-FAS polyclonal or monoclonal antibodies described herein to specifically bind to FAS in a biological sample. Any type of immunoassay format may be used, including, without limitation, enzyme immunoassays (EIA, ELISA), radioimmunoassay (RIA), fluoroimmunoassay (FIA), chemiluminescent immunoassay (CLIA), counting immunoassay (CIA), immunohistochemistry (IHC), agglutination, nephelometry, turbidimetry or Western Blot. These and other types of immunoassays are well-known and are described in the literature, for example, in Immunochemistry, Van Oss and Van Regenmortel (Eds), CRC Press, 1994; The Immunoassay Handbook, D. Wild (Ed.), Elsevier Ltd., 2005; and the references disclosed therein.
[0052] The preferred assay format for the present invention is the enzyme-linked immunosorbent assay (ELISA) format. ELISA is a highly sensitive technique for detecting and measuring antigens or antibodies in a solution in which the solution is run over a surface to which immobilized antibodies specific to the substance have been attached, and if the substance is present, it will bind to the antibody layer, and its presence is verified and visualized with an application of antibodies that have been tagged or labeled so as to permit detection. ELISAs combine the high specificity of antibodies with the high sensitivity of enzyme assays by using antibodies or antigens coupled to an easily assayed enzyme that possesses a high turnover number such as alkaline phosphatase (AP) or horseradish peroxidase (HRP), and are very useful tools both for determining antibody concentrations (antibody titer) in sera as well as for detecting the presence of antigen.
[0053] There are many different types of ELISAs; the most common types include “direct ELISA,” “indirect ELISA,” “sandwich ELISA” and cell-based ELISA (C-ELISA). Performing an ELISA involves at least one antibody with specificity for a particular antigen. The sample with an unknown amount of antigen is immobilized on a solid support (usually a polystyrene microtiter plate) either non-specifically (via adsorption to the surface) or specifically (via capture by another antibody specific to the same antigen, in a “sandwich” ELISA). After the antigen is immobilized the detection antibody is added, forming a complex with the antigen. The detection antibody can be covalently linked to an enzyme, or can itself be detected by a secondary antibody which is linked to an enzyme through bioconjugation. Between each step the plate typically is washed with a mild detergent solution to remove any proteins or antibodies that are not specifically bound. After the final wash step the plate is developed by adding an enzymatic substrate tagged with a detectable label to produce a visible signal, which indicates the quantity of antigen in the sample.
[0054] In a typical microtiter plate sandwich immunoassay, an antibody (“capture antibody”) is adsorbed or immobilized onto a substrate, such as a microtiter plate. Monoclonal antibodies are preferred as capture antibodies due to their greater specificity, but polyclonal antibodies also may be used. When the test sample is added to the plate, the antibody on the plate will bind the target antigen from the sample, and retain it in the plate. When a second antibody (“detection antibody”) or antibody pair is added in the next step, it also binds to the target antigen (already bound to the monoclonal antibody on the plate), thereby forming an antigen ‘sandwich’ between the two different antibodies.
[0055] This binding reaction can then be measured by radio-isotopes, as in a radio-immunoassay format (RIA); by enzymes, as in an enzyme immunoassay format (EIA or ELISA); or other detectable label, attached to the detection antibody. The label generates a color signal proportional to the amount of target antigen present in the original sample added to the plate. Depending on the immunoassay format, the degree of color can be detected and measured with the naked eye (as with a home pregnancy test), a scintillation counter (for an RIA), or with a spectrophotometric plate reader (for an EIA or ELISA).
[0056] The assay then is carried out according to the following general steps:
[0057] Step 1: Capture antibodies are adsorbed onto the well of a plastic microtiter plate (no sample added);
[0058] Step 2: A test sample (such as human serum) is added to the well of the plate, under conditions sufficient to permit binding of the target antigen to the capture antibody already bound to the plate, thereby retaining the antigen in the well;
[0059] Step 3: Binding of a detection antibody or antibody pair (with enzyme or other detectable moiety attached) to the target antigen (already bound to the capture antibody on the plate), thereby forming an antigen “sandwich” between the two different antibodies. The detectable label on the detection antibodies will generate a color signal proportional to the amount of target antigen present in the original sample added to the plate.
[0060] In an alternative embodiment, sometimes referred to as an antigen-down immunoassay, the analyte (rather than an antibody) is coated onto a substrate, such as a microtiter plate, and used to bind antibodies found in a sample. When the sample is added (such as human serum), the antigen on the plate is bound by antibodies (IgE for example) from the sample, which are then retained in the well. A species-specific antibody (anti-human IgE for example) labeled with an enzyme such as horse radish peroxidase (HRP) is added next, which, binds to the antibody bound to the antigen on the plate. The higher the signal, the more antibodies there are in the sample.
[0061] In another embodiment, an immunoassay may be structured in a competitive inhibition format. Competitive inhibition assays are often used to measure small analytes because competitive inhibition assays only require the binding of one antibody rather than two as is used in standard ELISA formats. In a sequential competitive inhibition assay, the sample and conjugated analyte are added in steps similar to a sandwich assay, while in a classic competitive inhibition assay, these reagents are incubated together at the same time.
[0062] In a typical sequential competitive inhibition assay format, a capture antibody is coated onto a substrate, such as a microtiter plate. When the sample is added, the capture antibody captures free analyte out of the sample. In the next step, a known amount of analyte labeled with a detectable label, such as an enzyme or enzyme substrate, added. The labeled analyte also attempts to bind to the capture antibody adsorbed onto the plate, however, the labeled analyte is inhibited from binding to the capture antibody by the presence of previously bound analyte from the sample. This means that the labeled analyte will not be bound by the monoclonal on the plate if the monoclonal has already bound unlabeled analyte from the sample. The amount of unlabeled analyte in the sample is inversely proportional to the signal generated by the labeled analyte. The lower the signal, the more unlabeled analyte there is in the sample. A standard curve can be constructed using serial dilutions of an unlabeled analyte standard. Subsequent sample values can then be read off the standard curve as is done in the sandwich ELISA formats. The classic competitive inhibition assay format requires the simultaneous addition of labeled (conjugated analyte) and unlabeled analyte (from the sample). Both labeled and unlabeled analyte then compete simultaneously for the binding site on the monoclonal capture antibody on the plate. Like the sequential competitive inhibition format, the colored signal is inversely proportional to the concentration of unlabeled target analyte in the sample. Detection of labeled analyte can be read on a microtiter plate reader.
[0063] In addition to microtiter plates, immunoassays are also may be configured as rapid tests, such as a home pregnancy test. Like microtiter plate assays, rapid tests use antibodies to react with antigens and can be developed as sandwich formats, competitive inhibition formats, and antigen-down formats. With a rapid test, the antibody and antigen reagents are bound to porous membranes, which react with positive samples while channeling excess fluids to a non-reactive part of the membrane. Rapid immunoassays commonly come in two configurations: a lateral flow test where the sample is simply placed in a well and the results are read immediately; and a flow through system, which requires placing the sample in a well, washing the well, and then finally adding an analyte-detectable label conjugate and the result is read after a few minutes. One sample is tested per strip or cassette. Rapid tests are faster than microtiter plate assays, require little sample processing, are often cheaper, and generate yes/no answers without using an instrument. However, rapid immunoassays are not as sensitive as plate-based immunoassays, nor can they be used to accurately quantitate an analyte.
[0064] The preferred technique for use in the present invention to detect the amount of FAS in circulating cells is the sandwich ELISA, in which highly specific monoclonal antibodies are used to detect sample antigen. The sandwich ELISA method comprises the following general steps:
[0065] 1. Prepare a surface to which a known quantity of capture antibody is bound;
[0066] 2. (Optionally) block any non specific binding sites on the surface;
[0067] 3. Apply the antigen-containing sample to the surface;
[0068] 4. Wash the surface, so that unbound antigen is removed;
[0069] 5. Apply primary (detection) antibodies that bind specifically to the bound antigen;
[0070] 6. Apply enzyme-linked secondary antibodies which are specific to the primary antibodies;
[0071] 7. Wash the plate, so that the unbound antibody-enzyme conjugates are removed;
[0072] 8. Apply a chemical which is converted by the enzyme into a detectable (e.g., color or fluorescent or electrochemical) signal; and
[0073] 9. Measure the absorbance or fluorescence or electrochemical signal to determine the presence and quantity of antigen.
[0074] In an alternate embodiment, the primary antibody (step 5) is linked to an enzyme; in this embodiment, the use of a secondary antibody conjugated to an enzyme (step 6) is not necessary if the primary antibody is conjugated to an enzyme. However, use of a secondary-antibody conjugate avoids the expensive process of creating enzyme-linked antibodies for every antigen one might want to detect. By using an enzyme-linked antibody that binds the Fc region of other antibodies, this same enzyme-linked antibody can be used in a variety of situations. The major advantage of a sandwich ELISA is the ability to use crude or impure samples and still selectively bind any antigen that may be present. Without the first layer of “capture” antibody, any proteins in the sample (including serum proteins) may competitively adsorb to the plate surface, lowering the quantity of antigen immobilized.
[0075] In a currently preferred embodiment of the present invention, a solid phase substrate, such as a microtiter plate or strip, is treated in order to fix or immobilize a capture antibody to the surface of the substrate. The material of the solid phase is not particularly limited as long as it is a material of a usual solid phase used in immunoassays. Examples of such material include polymer materials such as latex, rubber, polyethylene, polypropylene, polystyrene, a styrene-butadiene copolymer, polyvinyl chloride, polyvinyl acetate, polyacrylamide, polymethacrylate, a styrene-methacrylate copolymer, polyglycidyl methacrylate, an acrolein-ethyleneglycol dimethacrylate copolymer, polyvinylidene difluoride (PVDF), and silicone; agarose; gelatin; red blood cells; and inorganic materials such as silica gel, glass, inert alumina, and magnetic substances. These materials may be used singly or in combination of two or more thereof.
[0076] The form of the solid phase is not particularly limited insofar as the solid phase is in the form of a usual solid phase used in immunoassays, for example in the form of a microtiter plate, a test tube, beads, particles, and nanoparticles. The particles include magnetic particles, hydrophobic particles such as polystyrene latex, copolymer latex particles having hydrophilic groups such as an amino group and a carboxyl group on the surfaces of the particles, red blood cells and gelatin particles. The solid phase is preferably a microtiter plate or strip, such as those available from Cell Signalling Technology, Inc.
[0077] The capture antibody preferably is one or more monoclonal anti-FAS antibodies described herein that specifically bind to at least a portion of one or more of the peptide sequences of SEQ ID NO. 1-5. Where microtiter plates or strips are used, the capture antibody is immobilized within the wells. Techniques for coating and/or immobilizing proteins to solid phase substrates are known in the art, and can be achieved, for example, by a physical adsorption method, a covalent bonding method, an ionic bonding method, or a combination thereof. See, e.g., W. Luttmann et al., Immunology, Ch. 4.3.1 (pp. 92-94), Elsevier, Inc. (2006) and the references cited therein. For example, when the binding substance is avidin or streptavidin, a solid phase to which biotin was bound can be used to fix avidin or streptavidin to the solid phase. The amounts of the capture antibody, the detection antibody and the solid phase to be used can also be suitably established depending on the antigen to be measured, the antibody to be used, and the type of the solid phase or the like. Protocols for coating microtiter plates with capture antibodies, including tools and methods for calculating the quantity of capture antibody, are described for example, on the websites for Immunochemistry Technologies, LLC (Bloomington, Minn.) and Meso Scale Diagnostics, LLC (Gaithersburg, Md.).
[0078] The detection antibody can be any anti-FAS antibody. Anti-FAS antibodies are commercially available, for example, from Cell Signalling Technologies, Inc., Santa Cruz Biotechnology, EMD Biosciences, and others. The detection antibody also may be an anti-FAS antibody as disclosed herein that is specific for one or more of SEQ ID NOs. 1-5. In one embodiment, the detection antibody may be directly conjugated with a detectable label, or an enzyme. If the detection antibody is not conjugated with a detectable label or an enzyme, then a labeled secondary antibody that specifically binds to the detection antibody is included. Such detection antibody “pairs” are commercially available, for example, from Cell Signaling Technologies, Inc.
[0079] Techniques for labeling antibodies with detectable labels are well-established in the art. As used herein, the term “detectable label” refers to a composition detectable by spectroscopic, photochemical, biochemical, immunochemical, or chemical means. The detectable label can be selected, e.g., from a group consisting of radioisotopes, fluorescent compounds, chemiluminescent compounds, enzymes, and enzyme co-factors, or any other labels known in the art. See, e.g., Zola, Monoclonal Antibodies: A Manual of Techniques, pp. 147-158 (CRC Press, Inc. 1987). A detectable label can be attached to the subject antibodies and is selected so as to meet the needs of various uses of the method which are often dictated by the availability of assay equipment and compatible immunoassay procedures. Appropriate labels include, without limitation, radionuclides, enzymes (e.g., alkaline phosphatase, horseradish peroxidase, luciferase, or β-galactosidase), fluorescent moieties or proteins (e.g., fluorescein, rhodamine, phycoerythrin, GFP, or BFP), or luminescent moieties (e.g., Evidot® quantum dots supplied by Evident Technologies, Troy, N.Y., or Qdot™ nanoparticles supplied by the Quantum Dot Corporation, Palo Alto, Calif.).
[0080] Preferably, the sandwich immunoassay of the present invention comprises the step of measuring the labeled secondary antibody, which is bound to the detection antibody, after formation of the capture antibody-antigen-detection antibody complex on the solid phase. The method of measuring the labeling substance can be appropriately selected depending on the type of the labeling substance. For example, when the labeling substance is a radioisotope, a method of measuring radioactivity by using a conventionally known apparatus such as a scintillation counter can be used. When the labeling substance is a fluorescent substance, a method of measuring fluorescence by using a conventionally known apparatus such as a luminometer can be used.
[0081] When the labeling substance is an enzyme, a method of measuring luminescence or coloration by reacting an enzyme substrate with the enzyme can be used. The substrate that can be used for the enzyme includes a conventionally known luminescent substrate, calorimetric substrate, or the like. When an alkaline phosphatase is used as the enzyme, its substrate includes chemilumigenic substrates such as CDP-star® (4-chloro-3-(methoxyspiro(1,2-dioxetane-3,2′-(5′-chloro)tricyclo[3.3.1.1.-sup.3.7]decane)-4-yl)disodium phenylphosphate) and CSPD® (3-(4-methoxyspiro(1,2-dioxetane-3,2-(5′-chloro)tricyclo[3.3.1.1.sup.3.7]-decane)-4-yl)disodium phenylphosphate) and colorimetric substrates such as p-nitrophenyl phosphate, 5-bromo-4-chloro-3-indolyl-phosphoric acid (BCIP), 4-nitro blue tetrazolium chloride (NBT), and iodonitro tetrazolium (INT). These luminescent or calorimetric substrates can be detected by a conventionally known spectrophotometer, luminometer, or the like.
[0082] In a currently preferred embodiment, the detectable labels comprise quantum dots (e.g., Evidot® quantum dots supplied by Evident Technologies, Troy, N.Y., or Qdot™ nanoparticles supplied by the Quantum Dot Corporation, Palo Alto, Calif.). Techniques for labeling proteins, including antibodies, with quantum dots are known. See, e.g., Goldman et al., Phys. Stat. Sol., 229(1): 407-414 (2002); Zdobnova et al., J. Biomed. Opt., 14(2):021004 (2009); Lao et al., JACS, 128(46):14756-14757 (2006); Mattoussi et al., JACS, 122(49):12142-12150 (2000); and Mason et al., Methods in Molecular Biology: NanoBiotechnology Protocols, 303:35-50 (Springer Protocols, 2005). Quantum-dot antibody labeling kits are commercially available, e.g., from Invitrogen (Carlsbad, Calif.) and Millipore (Billerica, Mass.).
[0083] The sandwich immunoassay of the present invention may comprise one or more washing steps. By washing, the unreacted reagents can be removed. For example, when the solid phase comprises a strip of microtiter wells, a washing substance or buffer is contacted with the wells after each step. Examples of the washing substance that can be used include 2-[N-morpholino]ethanesulfonate buffer (MES), or phosphate buffered saline (PBS), etc. The pH of the buffer is preferably from about pH 6.0 to about pH 10.0. The buffer may contain a detergent or surfactant, such as Tween 20.
[0084] The sandwich immunoassay can be carried out under typical conditions for immunoassays. The typical conditions for immunoassays comprise those conditions under which the pH is about 6.0 to 10.0 and the temperature is about 30 to 45° C. The pH can be regulated with a buffer, such as phosphate buffered saline (PBS), a triethanolamine hydrochloride buffer (TEA), a Tris-HCl buffer or the like. The buffer may contain components used in usual immunoassays, such as a surfactant, a preservative and serum proteins. The time of contacting the respective components in each of the respective steps can be suitably established depending on the antigen to be measured, the antibody to be used, and the type of the solid phase or the like.
Kits
[0085] The invention further provides kits for performing an immunoassay using the antibodies of the present invention. The kits comprise, at a minimum, one or more of the present antibodies fur use as capture or detection agents for determining the presence and amount of FAS in a biological sample. The kit optionally may include reagents useful in performing the assay, additional antibodies for use in capture/detection of FAS, detection reagents, blocking reagents, or washing reagents. The kits may include instructions for performing an immunoassay using the antibodies and reagents.
Utility
[0086] The present invention provides antibodies that are specific for and highly reactive with human FAS. Monoclonal antibodies according to the present invention are particularly useful as capture or detection agents in immunoassays for determining FAS expression. Immunoassays utilizing the present antibodies can be used to determine FAS expression from human tissue, cells or sera.
[0087] Immunoassays according to the present invention are especially useful for detecting and/or quantifying FAS expression in prostate cancer. It has been shown that FAS overexpression correlates with recurrence of prostate cancer and/or poor responsiveness to certain cancer therapies. Immunoassays of the present invention can be used in lieu of or in addition to standard PSA tests for determining the likelihood that a patient's prostate cancer will recur, and/or if a patient is likely to benefit from certain therapies, e.g., androgen ablation.
[0088] The invention is further illustrated by the following non-limiting examples.
EXAMPLES
Example 1
Preparation of Anti-FAS Monoclonal Antibodies
[0089] Four murine monoclonal antibodies were prepared by immunizing SCID mice with synthetic FAS peptides, and establishing hybridomas according to the general procedure described by Iyer et al., Ind. J. Med. Res., 123:651-564 (2006). Each mouse was immunized with one peptide as follows:
[0000]
Mouse/
Hybridoma
Peptide
A
SEQ ID NO. 1 VAQGQWEPSGXAP
B
SEQ ID NO. 2 PSGPAPTNXGALE
D
SEQ ID NO. 4 EVDPGSAELQKVLQGD
E
SEQ ID NO. 5 ELSSKADEASELAC
[0090] Humanized monoclonal antibodies were prepared as described by Carter et al., Proc. Natl. Acad. Sci. USA, 89:4285-89 (1992) from monoclonal antibodies A, B, D and E. The humanized monoclonal antibodies (MAbs) are referred to hereinafter as FAS 1, FAS 2, FAS 4 and FAS 5.
[0000]
Mouse/Hybridoma
Humanized MAb
A
FAS 1
B
FAS 2
D
FAS 4
E
FAS 5
[0091] FAS 4 humanized monoclonal antibody has been deposited with the American Type Culture Collection, ATCC Designation No. PTA-10801.
Example 2
Reactivity of Anti-FAS HuMAbs
[0092] The humanized FAS monoclonal antibodies prepared as described in Example 1 were screened against human sera using an ELISA assay according to the following protocol.
[0093] Microwell strips (12 8-well strips, Cell Signalling Technology, Inc.) were brought to room temperature. Wash buffer was prepared by diluting 20× wash buffer (Cell Lysis Buffer, CST#9803, Cell Signalling Technology, Inc.) with purified water to make 1× buffer.
[0094] Monoclonal antibodies FAS 1, FAS 2, FAS 4 and FAS 5 (Example 1) were used as capture antibodies. The capture antibodies were immobilized in the microwells as described below.
Preparation of Solutions
[0095] Capture Antibody Coating Solution: Antibodies to be used as capture antibodies are combined with 50 mM sodium carbonate (pH 9.6), 20 mM Tris HCl (pH 8.5) or 10 mM PBS (pH 7.2), to a protein concentration of between 1-10 μg/ml.
[0096] Blocking Solution: Blocking agent (BSA, FBS, nonfat dry milk, casein, or gelatin) is diluted with buffer to a concentration of approximately 1% for BSA, and approximately 5% (or greater) of FBS, nonfat dry milk, casein, or gelatin. Sodium azide is added to a concentration of approximately 0.05%.
[0097] Primary/Secondary Detection Antibody Solution: Primary (and secondary, if appropriate) detection antibodies are diluted in 1× blocking solution (to minimize nonspecific binding) to a concentration of 0.1-1.0 μg/ml.
[0098] Wash solution: 0.1M PBS or Tris-buffered saline (pH 7.4) is combined with Tween 20 (0.02%-0.05% v/v).
[0000] Coating of Microwell Plates with Capture Antibody
[0099] Add 100 μl of capture antibody coating solution to each well of a microwell plate or strip, and incubate for 1 hour at room temperature. Empty plate and tap out residual liquid. Block plate by adding 300 μl of blocking solution to the wells, incubating for 5 minutes, and tapping out residual liquid. The plates are ready to be used.
Preparing Cell Lysates
[0100] To prepare the sample, the pooled serum was centrifuged to separate cells, which then were lysed using sonication. The media was removed, and cold PBS was added. The PBS was removed and 0.5 mL of cold 1× Cell Lysis buffer plus 1 mM phenylmethylsulfonyl fluoride (PMSF) was added to each plate (10 cm in diameter) and incubated on ice for 5 minutes. The cells were carefully scraped off the plate, and transferred to an appropriate tube, kept on ice. The tubes of cell lysates were sonicated on ice, then microcentrifuged for 10 minutes at 4° C., after which the supernatant containing the cell lysate was transferred to a new tube. The supernatant is the cell lysate. The cell lysate was stored at −80° C. in single-use aliquots until needed.
Test Procedure
[0101] Bring microwell plates coated with capture antibody to room temperature. Add 100 μl of sample diluent (Cell Signalling Technology, Inc.) to a microcentrifuge tube, transfer 100 μl of cell lysate into the tube and vortex for a few seconds. 100 μl of each diluted cell lysate were added to the appropriate well, and sealed with tape. The plates were incubated for 2 hours at 37° C. (Alternatively, the plate may be incubated overnight at 4° C.).
[0102] The tape was removed and the plate contents decanted into a receptacle. The plates then were washed 4 times with 1× wash solution, 200 μl each time for each well. For each wash, the residual solution in each well was removed, but the wells were not allowed to become completely dry at any time. 100 μl of a solution containing the detection antibody (Cell Signaling Technology, Inc.) to each well. The plates were sealed with tape and incubated for 1 hour at 37° C.
[0103] The wash procedure described above then was repeated. 100 μl of HRP-Linked secondary antibody (red color) to each well. The plates were sealed with tape and incubated for 30 minutes at 37° C.
[0104] The wash procedure described above was again repeated. 100 μl of TMB Substrate (Cell Signaling Technology, Inc.) was added to each well. The plates were sealed with tape and incubated for 10 minutes at 37° C. or 30 minutes at 25° C. 100 μl of STOP Solution (Cell Signalling Technology, Inc.) was added to each well, and the plates were shaken gently for a few seconds. The initial color of positive reaction is blue, which changes to yellow upon addition of STOP Solution.
[0105] For visual determination, the plates must be read within 30 minutes after adding STOP Solution. For spectrophotometric determination, the absorbance must be read at 450 nm within 30 minutes after adding STOP Solution. For this Example, the absorbance was read using a fluorescence plate reader (Thermo Fisher Scientific, Inc.).
[0106] ELISA assays were performed to determine FAS expression in cells derived from the pooled sera of two prostate cancer patients. To prepare the sample, the pooled serum was centrifuged to separate cells, which then were lysed using sonication as described above.
[0107] The assay parameters were as follows:
[0108] Assay Parameters:
[0000]
Serial
Dilution
Volume/
Step
Reagent
dilution
buffer
Concentration
vile
Incubation
Ag
FAS 1, 2, 4
—
0.15M PBS
2 μg/mL
50 μL
1 hr @ 37 C.
coating
or 5
Blocking
SeaBlock*
—
—
NEAT
300 μL
30 min. @
37 C.
Sample
see below
5X
0.15M PBS
starting @
80 μ.L
30 min. @
Dilution
1:50
R.T.
Secondary
anti-Rb
—
15M PBS w
1:10000
50 μ.L
30 min. @
Ab
HRP**
0.05%
R.T.
Tween20
*Supplied by East Coat Biologics, North Berwick, ME
**Supplied by Cell Signaling Technology, Inc.
[0109] Absorbance was measured at 450 nm using a Thermo Shandon plate reader.
[0110] The data obtained for the ELISA using FAS 1, 2, 5 and 5 are shown in the tables below. In the tables, the term “pre-purification” refers to the murine monoclonal antibody prior to humanization and affinity purification, and “post-purification” refers to the monoclonal antibody after humanization and affinity purification. Data for pre-purified and post-purified antibodies are included for comparison.
[0111] The data for FAS 1 and 2 are shown in Table 2-1:
[0000]
TABLE 2-1
ELISA Results for FAS 1 and 2
Plate Design:
Sample Dilution
1:50
1:250
1:1250
1:6250
1:31250
1:156000
1
2
3
4
5
6
7
8
9
10
11
12
Pre-
0.03
0.02
0.014
0.01
0.01
0.01
0.008
0.005
0.01
0
0.01
0
purification
FAS 1
Pre-
0.07
0.06
0.022
0.04
0.01
0.02
0.01
0.007
0
0
0.01
0.01
purification
FAS 2
Post-
0.67
0.02
0.766
0.02
0.96
0.01
0.598
0.18
0.176
0.01
0.05
0
purification
FAS 1
Post-
0.59
0.02
0.659
0.03
0.78
0.02
0.439
0.12
0.12
0
0.03
0.02
purification
FAS 2
[0112] FIG. 1 shows the data in Table 1 in graphical form. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs. The graph shows that the FAS 1 and 2 antibodies were able to detect significant levels of FAS in the patient sera even at very high dilutions.
[0113] The data obtained for the ELISA using FAS 4 are shown in Table 2-2:
[0000]
TABLE 2-2
ELISA Results for FAS 4
Plate Design:
Sample Dilution
1:50
1:250
1:1250
1:6250
1:31250
1:156000
1
2
3
4
5
6
7
8
9
10
11
12
Pre-
0.03
0.02
0.014
0.01
0.01
0.01
0.008
0.005
0.01
0
0.01
0
purification
FAS 4
Pre-
0.07
0.06
0.022
0.04
0.01
0.02
0.01
0.007
0
0
0.01
0.01
purification
FAS 4a
Post-
0.67
0.02
0.766
0.02
0.96
0.01
0.598
0.007
0.18
0.01
0.05
0
purification
FAS 4
Post-
0.59
0.02
0.659
0.03
0.78
0.02
0.439
0.009
0.12
0
0.03
0.02
purification
FAS 4a
[0114] FAS 4 and FAS 4a represent two separate batches of FAS 4. FIG. 2 shows the data in graphical form. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs. The graph shows that the FAS 4 antibody was able to detect significant levels of FAS in the patient sera even at very high dilutions.
[0115] The data obtained for the ELISA using FAS 5 are shown in Table 2-3:
[0000]
TABLE 2-3
ELISA Results for FAS 5
PlateDesign:
Sample Dilution
1:50
1:250
1:1250
1:6250
1:31250
1:156000
1
2
3
4
5
6
7
8
9
10
11
12
Pre-
0.02
0
0.02
0.01
0.03
0.02
0.01
0.013
0.02
0.01
0.02
0.02
purification
FAS 5
Pre-
0
0.02
0.03
0.02
0.05
0.02
0.02
0
0.01
0.01
0.03
0.09
purification
FAS 5a
Post-
0.59
0.06
1.434
0.08
1.15
0.04
1.484
−0.15
1.07
0.03
0.27
0.01
purification
FAS 5
Post-
0.46
0.3
0.441
0.01
0.41
0
0.234
0.018
0.09
0.2
0.09
0.08
purification
FAS 5a
[0116] FAS 5 and FAS 5a represent two separate batches of FAS 5. FIG. 3 shows the data in graphical form. For each dilution, the two left columns represent the pre-purification MAbs, and the two right columns represent the post-purification MAbs. The graph shows that the FAS 5 antibody was able to detect significant levels of FAS in the patient sera even at very high dilutions.
Example 3
Comparison of FAS and PSA as Prognostic Indicators in Prostate Cancer
[0117] Biopsy specimens from ninety patients diagnosed with prostate cancer (PCa) were prepared and analyzed as described below. All patients had been treated by androgen ablation.
[0118] Tissue microarrays (TMAs) were prepared as described in US 2008/0206777 A1. In addition to the 90 prostate cancer specimens, TMAs containing normal prostate tissue, benign prostatic hyperplasia (BPH) and normal (non-cancerous) tissues were prepared and analyzed.
[0000]
TABLE A
Tissue Micro Arrays
Prostate
This array contained the patient samples obtained from
Cancer
patients afflicted with recurrent/metastatic and non-
Progression
recurrent prostate cancer. The characteristics of these 90
Array
samples are shown in Table C.
Normal
This array contained samples of normal (non-cancerous)
Prostate/
prostate tissue, and benign prostatic hyperplasia (BPH)
BPH
tissue. This array was included as a negative control to
Screening
confirm that FAS overexpression does not occur in non-
Array
cancerous prostate tissue.
Test Array
This array contained samples of the following normal
(TE-30 Array)
(non-cancerous) tissues: colon, liver, lung, prostate and
breast. This array is included for antibody dilution and
as a negative control to confirm that FAS overexpression
does not occur in any of these normal tissues.
[0000]
TABLE B
The 90 prostate cancer samples had the following characteristics:
Number
Number
Primary Tumor Stage
of Patients
of Patients with Recurrence of PCa
2a
13
2
2b
4
2
2c
27
9
3a
25
8
3b
19
11
3c
0
0
4
2
2
Total
90
34
[0119] FAS expression was determined by immunohistochemistry (IHC) according to the method described in US 2008/0206777 A1, using MAb D (Example 1) as the detection (primary) antibody. The detection antibody was visualized using a biotinylated link antibody and streptavidin-HRP as described in US 2008/0206777 A1. The results for the 90 prostate cancer samples are shown in Table C below; in Table C, FAS overexpression (at least 2-fold compared to expression levels in normal tissue or cells) is indicated by a + sign.
[0120] The results for the TE-30 array and the Normal Prostate/BPH Screening Array were negative for FAS expression.
[0000]
TABLE C
Clinical and pathological data on 90 cases of treated (androgen ablated) prostate cancer
Degree of
Biopsy
Months
regression
Patient
Age
Gleason
Pre-therapy PSA
of
(3 grade
TNM
No.
(years)
score
(ng/ml)
FAS
therapy
system)
2002
1
69
3 + 4 = 7
8.7
+
3
Poor
pT3aN0R0
2
70
3 + 3 = 6
7.0
+
1
Poor
pT3aNXR0
3
72
2 + 3 = 5
21.0
−
6
Excellent
pT2cN0R0
4
68
2 + 2 = 4
14.0
+
7
Poor
pT2cNXR0
5
60
2 + 3 = 5
24.0
−
3
Good
pT2cNXR0
6
68
3 + 3 = 6
+
+
3
Poor
pT3bN0R1
7
58
3 + 3 = 6
10.2
+
3
Poor
pT3aNXR1
8
57
3 + 3 = 6
9.8
+
3
Poor
pT3aNXR0
9
70
3 + 3 = 6
5.2
+
2
Poor
pT2cN0R1
10
64
3 + 3 = 6
2.6
−
3
Good
pT2cNXR1
11
65
3 + 3 = 6
5.0
+
5
Poor
pT3aN0R0
12
66
4 + 3 = 7
6.0
+
5
Poor
pT3aN0R1
13
61
3 + 3 = 6
7.6
−
6
Good
pT3aN0R0
14
68
3 + 4 = 7
9.7
−
3
Good
pT2cN0R1
15
67
3 + 3 = 6
9.4
+
6
Poor
pT3bN0R0
16
57
2 + 3 = 5
19.0
+
2
Good
pT2cN0R0
17
67
3 + 3 = 6
9.5
+
7
Poor
pT3bN1R0
18
57
3 + 4 = 7
34.0
+
4
Poor
pT3bNXR1
19
58
3 + 3 = 6
18.0
−
11
Excellent
pT3aN0R0
20
72
3 + 3 = 6
6.5
+
2
Poor
pT3aN0R0
21
70
3 + 3 = 6
8.7
+
3
Poor
pT3aN0R1
22
65
4 + 3 = 7
16.3
+
5
Poor
pT2cN0R1
23
68
3 + 4 = 7
41.7
−
6
Excellent
pT4N0R1
24
62
3 + 3 = 6
13.0
+
3
Poor
pT3aN0R0
25
64
2 + 3 = 5
2.4
+
1
Poor
pT2bN0R0
26
78
3 + 4 = 7
13.4
−
2
Excellent
pT2cN0R0
27
56
3 + 4 = 7
17.1
−
24
Good
pT3bN0R1
28
65
3 + 3 = 6
16.0
+
4
Poor
pT3bN0R0
29
72
3 + 3 = 6
19.0
+
2
Poor
pT3aN0R0
30
68
3 + 5 = 8
2.15
+
1
Poor
pT3aN0R0
31
66
4 + 3 = 7
12.0
+
12
Poor
pT3bN1R0
32
65
3 + 3 = 6
2.4
+
4
Poor
pT3bN0R1
33
69
3 + 3 = 6
7.0
+
1
Poor
pT2aNXR0
34
68
3 + 3 = 6
17.5
−
5
Good
pT2cN0R1
35
67
3 + 4 = 7
7.3
+
6
Poor
pT3aNXR1
36
53
2 + 2 = 4
3.7
−
3
Good
pT2cN0R0
37
66
3 + 3 = 6
10.6
−
2
Poor
pT2cN0R0
38
74
3 + 3 = 6
15.9
−
2
Poor
pT2cN0R0
39
69
4 + 4 = 8
31.0
−
6
Good
pT2cN0R0
40
70
3 + 3 = 6
7.3
+
3
Poor
pT3bN0R1
41
59
4 + 4 = 8
27.0
+
2
Poor
pT3aN0R0
42
67
3 + 4 = 7
16.5
+
1
Poor
PT2cNXR0
43
62
3 + 3 = 6
5.4
−
2
Good
pT3aNXR1
44
69
4 + 4 = 8
8.2
+
5
Poor
PT2cN0R1
45
73
3 + 3 = 6
1.8
+
2
Poor
pT3aNXR0
46
59
3 + 4 = 7
9.3
+
6
Poor
pT2aN0R0
47
69
3 + 3 = 6
12.6
+
3
Poor
pT2cN0R0
48
66
4 + 3 = 7
13.5
+
6
Poor
pT2aN0R0
49
50
4 + 3 = 7
101.0
+
4
Poor
pT4N1R1
50
53
3 + 3 = 6
10.0
+
1
Poor
pT2aN0R1
51
70
4 + 4 = 8
10.9
+
3
Poor
pT2aN0R0
52
55
3 + 3 = 6
9.7
+
4
Good
pT2cN0R0
53
61
3 + 3 = 6
6.4
+
3
Poor
pT3bN1R1
54
74
3 + 3 = 6
28.0
−
6
Excellent
pT3bN0R0
55
71
3 + 4 = 7
8.3
+
3
Good
pT3aN0R0
56
71
3 + 3 = 6
17.0
+
1
Poor
pT2cN0R1
57
67
3 + 3 = 6
2.0
−
5
Excellent
pT2aN0R0
58
62
3 + 3 = 6
16.6
−
3
Good
pT2cN0R0
59
69
3 + 3 = 6
6.31
+
1
Poor
pT2cNXR0
60
72
3 + 3 = 6
11.8
+
2
Poor
pT2cN0R0
61
65
3 + 3 = 6
5.2
+
2
Poor
pT2cN0R0
62
66
3 + 4 = 7
7.4
+
1
Poor
pT3bN0R1
63
66
4 + 3 = 7
13.5
−
3
Good
pT3bN0R0
64
74
3 + 3 = 6
12.8
−
4
Excellent
pT2aNXR0
65
66
3 + 3 = 6
9.8
+
2
Poor
pT3bN0R0
66
66
3 + 3 = 6
8.1
−
2
Good
pT2cNXR1
67
64
3 + 3 = 6
1.7
−
7
Excellent
pT2aNXR0
68
69
3 + 4 = 7
5.0
−
3
Good
pT2cN0R0
69
54
3 + 3 = 6
11.8
+
3
Good
PT3bNXR1
70
69
3 + 3 = 6
6.2
+
3
Good
PT3aN0R0
71
63
3 + 4 = 7
8.6
+
3
Good
pT2cNXR0
72
59
3 + 4 = 7
12.2
+
3
Poor
pT2aN0R1
73
65
4 + 3 = 7
4.8
+
2
Good
pT2aN0R0
74
64
3 + 3 = 6
7.6
+
1
Poor
pT2aN0R0
75
72
3 + 3 = 6
8.4
+
2
Poor
pT2cN0R1
76
68
3 + 4 = 7
7.8
+
3
Poor
pT2bN1R0
77
65
3 + 3 = 6
24.0
+
5
Good
pT2bN0R0
78
65
3 + 3 = 6
6.4
+
6
Poor
pT3aNXR0
79
71
3 + 4 = 7
9.6
−
2
Poor
pT3aN0R1
80
62
4 + 5 = 9
27.0
−
4
Excellent
pT2aN0R0
81
71
3 + 3 = 6
11.6
+
3
Good
pT2aN0R0
82
67
4 + 3 = 7
25.0
+
1
Poor
pT3bNXR1
83
67
3 + 3 = 6
22.9
+
9
Poor
pT3bN1R1
84
72
3 + 4 = 7
7.4
−
3
Excellent
pT2bN0R0
85
71
4 + 3 = 7
1.3
−
4
Excellent
PT3bN0R1
86
69
4 + 3 = 7
4.8
+
3
Poor
pT3aN0R1
87
68
4 + 3 = 7
9.0
+
1
Poor
pT3bN0R0
88
70
3 + 3 = 6
6.1
−
3
Good
pT3aN0R0
89
71
4 + 3 = 7
20.4
+
1
Poor
pT3aN0R0
90
65
3 + 3 = 6
5.8
+
3
Poor
pT3aNXR1
[0121] The results in Table C show that:
Significant FAS overexpression (e.g., 2-fold or higher) was detected in 62 of the patient biopsy samples; FAS overexpression correlates with recurrence of Pca and/or poor responsiveness to androgen ablation therapy in all but 8 of these patients (a positive correlation of 87%); In patients not exhibiting FAS overexpression (28 patients), the lack of FAS overexpression correlated with good or excellent tumor regression after treatment with androgen ablation in all but three patients (a positive correlation of 89%).
[0125] However, the correlation between the absence of FAS overexpression and recurrence of PCa was lower: 9 patients out of 28 (32%) whose tumors showed no FAS overexpression experienced recurrence of their cancer.
[0126] In contrast, PSA was a much poorer prognostic indicator. Of the 90 patients in the study, 39 had pre-therapy PSA levels above 10 ng/ml. Of these, only 17 evidenced good or excellent tumor regression after androgen ablation therapy (a positive correlation of only 44%). PSA levels also showed a low correlation with recurrence: of the 39 patients having a pre-therapy PSA levels above 10 ng/ml, only 12 experienced tumor recurrence (a positive correlation of about 31%).
[0127] The pathological samples and clinical data for the patients listed in Table C were further analyzed using the Applied Imaging Ariol® platform (Genetix Corp., San Jose, Calif.) as well as the TMAJ software (Johns Hopkins University TMA Core Facility, Baltimore, Md.). The data analyzed included the PSA serum levels, FAS expression levels, recurrence of cancer, metastasis of cancer, and the length of time until recurrence or metastasis. The results showed a strong correlation between FAS expression and recurrence: patients whose disease is characterized by a high level of FAS expression experienced higher levels of recurrence and shorter times until recurrence of their disease. The results are summarized below:
[0000]
Correlation of FAS Expression with Recurrence
Univariate Analysis
Multivariate Analysis
Hazard Ratio (95% CI)
P-value
Hazard Ratio (95% CI)
P-value
1.69 (1.41-2.04)
<0.0001
1.48 (1.21-1.80)
0.0001
[0128] In contrast, the same analysis showed a poor correlation between PSA levels and recurrence of disease. In many cases, the presence of high levels of PSA was not predictive of recurrence of a patient's disease.
[0129] The results further showed a strong correlation between FAS expression and metastasis: patients whose disease is characterized by a high level of FAS expression experienced higher levels of metastasis and shorter times until metastasis of their disease. These results are summarized below:
[0000]
Correlation of FAS Expression with Metastasis
Univariate Analysis
Hazard Ratio (95% CI)
P-value
1.32 (1.04-1.68)
0.02
[0130] The results of this study indicate that FAS expression is a promising prognostic indicator for prostate cancer.
Example 4
ELISA Assay for FAS Expression in DU-145 PCa Cells
[0131] Microwell strips (12 8-well strips, Cell Signalling Technology, Inc.) were brought to room temperature. Wash buffer was prepared by diluting 20× wash buffer (Cell Lysis Buffer, CST# 9803, Cell Signalling Technology, Inc.) with purified water to make 1× buffer.
[0132] Two monoclonal antibodies (MAbs D and E, Example 1) were used as capture antibodies. The capture antibodies were immobilized in the microwells according to the following procedure:
Preparation of Solutions
[0133] Capture Antibody Coating Solution: Antibodies to be used as capture antibodies are combined with 50 mM sodium carbonate (pH 9.6), 20 mM Tris HCl (pH 8.5) or 10 mM PBS (pH 7.2), to a protein concentration of between 1-10 μg/ml.
[0134] Blocking Solution: Blocking agent (BSA, FBS, nonfat dry milk, casein, or gelatin) is diluted with buffer to a concentration of approximately 1% for BSA, and approximately 5% (or greater) of FBS, nonfat dry milk, casein, or gelatin. Sodium azide is added to a concentration of approximately 0.05%.
[0135] Primary/Secondary Detection Antibody Solution: Primary (and secondary, if appropriate) detection antibodies are diluted in 1× blocking solution (to minimize nonspecific binding) to a concentration of 0.1-1.0 μg/ml.
[0136] Wash solution: 0.1M PBS or Tris-buffered saline (pH 7.4) is combined with Tween 20 (0.02%-0.05% v/v).
[0000] Coating of Microwell Plates with Capture Antibody
[0137] Add 100 μl of capture antibody coating solution to each well of a microwell plate or strip, and incubate for 1 hour at room temperature. Empty plate and tap out residual liquid. Block plate by adding 300 μl of blocking solution to the wells, incubating for 5 minutes, and tapping out residual liquid. The plates are ready to be used.
Preparing Cell Lysates
[0138] The media was aspirated from cultures of DU-145 prostate cancer cells (obtained from the National Cancer Institute), and fresh media was added. The cells were harvested under non-denaturing conditions according to the following protocol. The media was removed, and cold PBS was added. The PBS was removed and 0.5 mL of cold 1× Cell Lysis buffer plus 1 mM phenylmethylsulfonyl fluoride (PMSF) was added to each plate (10 cm in diameter) and incubated on ice for 5 minutes. The cells were carefully scraped off the plate, and transferred to an appropriate tube, kept on ice. The tubes of cell lysates were sonicated on ice, then microcentrifuge d for 10 minutes at 4° C., after which the supernatant containing the cell lysate was transferred to a new tube. The supernatant is the cell lysate. The cell lysate was stored at −80° C. in single-use aliquots until needed.
Test Procedure
[0139] Bring microwell plates coated with capture antibody to room temperature. Add 100 μl of sample diluent (Cell Signalling Technology, Inc.) to a microcentrifuge tube, transfer 100 μl of cell lysate into the tube and vortex for a few seconds. 100 μl of each diluted cell lysate were added to the appropriate well, and sealed with tape. The plates were incubated for 2 hours at 37° C. (Alternatively, the plate may be incubated overnight at 4° C.).
[0140] The tape was removed and the plate contents decanted into a receptacle. The plates then were washed 4 times with 1× wash solution, 200 μl each time for each well. For each wash, the residual solution in each well was removed, but the wells were not allowed to become completely dry at any time. 100 μl of a solution containing the detection antibody (Cell Signaling Technology, Inc.) to each well. The plates were sealed with tape and incubated for 1 hour at 37° C.
[0141] The wash procedure described above then was repeated. 100 μl of HRP-Linked secondary antibody (red color) to each well. The plates were sealed with tape and incubated for 30 minutes at 37° C.
[0142] The wash procedure described above was again repeated. 100 μl of TMB Substrate (Cell Signaling Technology, Inc.) was added to each well. The plates were sealed with tape and incubated for 10 minutes at 37° C. or 30 minutes at 25° C. 100 μl of STOP Solution (Cell Signalling Technology, Inc.) was added to each well, and the plates were shaken gently for a few seconds. The initial color of positive reaction is blue, which changes to yellow upon addition of STOP Solution.
Results
[0143] For visual determination, the plates must be read within 30 minutes after adding STOP Solution. For spectrophotometric determination, the absorbance must be read at 450 nm within 30 minutes after adding STOP Solution. For this Example, the absorbance was read using a fluorescence plate reader (Thermo Fisher Scientific, Inc.).
[0144] Significant levels of FAS expression were observed from the cells, indicating that the assay is effective.
Example 5
ELISA Assay for FAS Expression in Sera from PCa Patients
[0145] ELISA assays were performed to determine FAS expression in cells derived from the sera of two prostate cancer patients (Patients 30 and 87 from Table C). To prepare the sample, the sera were centrifuged to separate cells, which then were lysed using sonication.
[0146] Anti-FAS MAbs D and E were used as capture antibodies. In addition, two rabbits (New Zealand White Rabbits, Maine Biotechnology Services, Inc.) were injected with peptides D and E (SEQ. ID. NOs. 4 and 5), and antisera from the rabbits were used to titrate the MAbs. The assay was performed according to the procedure set forth in Example 4; the assay parameters were as follows:
[0000]
Assay parameters:
Serial
Step
Reagent
dilution
Dilution buffer
Concentration
Vol/well
Incubation
Ab
MAb D or E
—
0.15M PBS
2 μg/ml
50 μl
1 hr@37° C.
coating
Blocking
Sea Block*
—
—
NEAT
300 μl
30 min
@37° C.
Sample
1:50-1:156000
5X
0.15M PBS
Starting at 1:50
80 μl
30 min
dilution
@RT
Secondary
Anti-Rb
—
0.15M PBS w/
1:10000
50 μl
30 min
(detection)
HRP**
0.05%
@RT
Ab
Tween20
*Supplied by East Coat Biologics, North Berwick, ME
**Supplied by Cell Signaling Technology, Inc.
[0147] Absorbance was measured at 450 nm using a Thermo Shandon plate reader. MAb D is referred to in the charts below as “FAS 4” and MAb E is referred to as “FAS 5.”
[0148] The data obtained for the ELISA using MAb D are shown in Table 5-1:
[0000]
TABLE 5-1
Results for FAS 4 ELISA
Dilution:
1:50
1:250
1:1250
1:6250
1:31250
1:156000
Pre-bleed
0.100
−0.048
−0.030
−0.430
−0.040
−0.001
Rb 1
Pre-bleed
0.000
0.006
−0.010
−0.006
−0.900
−0.007
Rb 2
FAS1
1.000
1.250
1.310
1.010
0.221
0.168
FAS1
0.040
0.790
0.380
0.329
0.613
0.145
Pre-bleed
0.100
0.000
0.000
0.000
0.000
0.000
Rb 1
Pre-bleed
0.000
0.006
0.000
0.000
0.000
0.000
Rb 2
FAS1
1.000
1.250
1.310
1.010
0.221
0.168
FAS1
0.040
0.790
0.380
0.329
0.613
0.145
[0149] Reliable absorbance readings could not be obtained for the rabbit antisera under these conditions; it is believed that that concentration of fluorescent label was too dense, thereby masking the signal. The results show that the assay was able to detect significant levels of FAS in the patient sera even at very high dilutions.
[0150] The data obtained for the ELISA using MAb E are shown in Table 5-2:
[0000]
TABLE 5-2
Results for FAS 5 ELISA
Dilution:
1:50
1:250
1:1250
1:6250
1:31250
1:156000
Pre-bleed
0.360
0.660
0.156
−0.003
0.960
−0.001
Rb 1
Pre-bleed
−0.022
0.006
0.031
0.020
0.001
−0.064
Rb 2
FAS2
0.786
1.356
1.113
1.631
1.033
0.258
FAS2
0.690
0.580
0.850
0.630
0.950
0.530
Pre-bleed
0.330
0.869
0.523
0.330
0.200
1.200
Rb 1
Pre-bleed b 2
0.000
0.006
0.031
0.020
0.001
0.123
FAS2
0.786
1.960
1.520
1.520
1.430
1.630
FAS2
0.870
0.580
0.850
0.630
0.950
0.530
[0151] As with the FAS1 antibody, reliable absorbance readings could not be obtained for the rabbit antisera under these conditions. The results show that the assay was able to detect significant levels of FAS in the patient sera even at very high dilutions.
[0152] These data indicate that the MAbs are highly reactive, resulting in a sensitive and accurate assay for the presence of FAS in circulating cells obtained from patient sera.
REFERENCES
[0000]
1. Chirala et al., Proc. Natl. Acad. Sci. USA , (May 27, 1997) 94(11):5588-93.
2. Kuhajda et al., Proc. Natl. Acad. Sci. USA , (Mar. 28, 2000) 97(7):3450-4.
3. Rossi et al., Mol. Cancer. Res ., (August 2003), 1(10):707-15.
4. Visca et al., Anticancer Res ., (November-December 2004), 24(6):4169-73.
5. Takahiro et al., Clin. Cancer Res ., (June 2003), 9(6):2204-12
6. Shurbaji et al., Hum. Pathol ., (September 1996), 27(9):917-21.
7. Alo et al, Cancer , (February 1996), 77(3):474-82.
8. Baron et al., J. Cell Biochem ., (January 2004), 19(1):47-53.
9. Thompson et al., CA (May 2004), N Engl. J. Med., 350 (22): 2239-46.
10. Carter H B (May 2004), N. Engl. J. Med., 350 (22): 2292-4.
11. Herschman et al., (August 1997), Urology, 50 (2): 239-43.
12. Nadler et al., (August 1995), J. Urol., 154 (2 Pt 1): 407-13.
13. Catalona et al., (1997), JAMA, 277 (18): 1452-5. | Methods and immunoassays for the determination of fatty acid synthase (FAS) expression in patients having or suspected of having a proliferative disorder, especially prostate cancer, are disclosed. The sensitive method and assay detect the level of expression of FAS in a biological sample using antibodies that are highly specific for FAS. The method and assay can be used to monitor the progression of cancer, and/or to predict the efficacy of certain treatments or the likelihood of recurrence of the cancer. | 6 |
This application is a continuation of application Ser. No. 08/334,474, filed Nov. 4, 1994, now abandoned.
BACKGROUND OF THE INVENTION
The invention relates to the use of devices having information or patterns carried in or on some storage media, examples of which include photographic patterns, keys or the magnetic strip on credit cards. The invention provides for an apparatus and method allowing more than one pattern or set of information to be used with a given type of medium to facilitate use by the holder thereof with a pattern reading device and to reduce the numbers of separate information or pattern media carrying devices which must be used. Other uses and purposes for the present invention will also become known to one skilled in the art from the teachings herein.
1. Field of the Invention
The field of the invention includes the storage and use of information or patterns on or in operator usable medium, examples including credit cards, keys, holograms, photographs and the like, by use of various magnetic, electronic, optical and mechanical devices. Such information or patterns may be known, unknown, ordered or random, coherent or incoherent, there being no restriction on the types or nature of information or patterns with which the invention may be used. The operators may be human, animal or otherwise, and may involve different operators of different persons or types at various times.
2. Description of the Prior Art
It is well known to store particular information or patterns such as account numbers, bar codes, security codes, etc. on magnetic and optical storage medium embedded in small, sturdy and relatively inexpensive carriers such as credit cards. FIG. 1 shows for example a prior art credit card diagram having a strip of magnetic material 2 which is embedded in a plastic substrate 1 which magnetic strip carries a pattern of magnetization which is a magnetic representation of information or patterns relating to the credit card. FIG. 1 is shown in graphical form with the top and front edge view of the magnetic strip with a representation of the magnetic flux pattern recorded therein.
OBJECTS AND DISCLOSURE OF THE INVENTION
The invention described herein provides for a method and apparatus whereby a plurality of sets of patterns or information may be stored and utilized by a user. The invention allows access to numerous accounts, services, features, etc. with just one storage device, thereby eliminating the need to carry, store, remember or retain numerous data storage devices, data sets or patterns. Examples of applications for the present invention include the magnetic pattern information of a plurality of credit cards which may be stored in a single convenient card which a user may carry in order to replace a plurality of individual credit cards, programmable optical patterns such as bar codes or photographic patterns utilized for security applications and programmable key patterns which may be changed to accommodate different locks of mechanical, optical or electronic type.
The invention is useful with any sort of storage medium related to pluralities of sets of information, data or patterns which are desired to be used by a user. For example the invention may be used with mechanical, magnetic, electrical, optical, film, holographic or other recording or storage of information or patterns as will become apparent to one skilled in the art from the teachings given herein. The invention thus provides simulation of multiple sets of data, information or patterns stored in a spatial pattern by providing a memory or storage device for storing data from which the spatial patterns may be reconstructed. Also included is a programmable spatial device capable of reconstructing the spatial patterns under control of a circuit responsive to an external inputs which cause the programmable spatial device to be programmed to reconstruct the spatial patterns from the data stored in the memory. The spatial patterns may take on multiple dimensions and may be time varying and the memory may be electronic, mechanical, optical or other type as will be apparent to one of ordinary skill in the art from the teachings herein.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a drawing demonstrating a prior art credit card with a magnetic stripe.
FIG. 2 is a drawing demonstrating the preferred embodiment of the present invention.
FIG. 3 is a drawing explaining the operation of the preferred embodiment of the invention.
FIG. 4 is a drawing showing details of the programmable magnetic strip of the preferred embodiment of the invention.
FIG. 5 is a drawing showing a cross sectional view corresponding to FIG. 4.
FIG. 6 is a drawing showing the invention as used with a key.
FIG. 7 is a drawing showing another mechanical configuration of the preferred embodiment of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a drawing demonstrating a prior art credit card in diagram form, having a strip of magnetic material 2 which is embedded in a plastic substrate 1 which magnetic strip carries a pattern of magnetization which is a magnetic representation of information or patterns relating to the credit card. FIG. 1 shown in graphical form the top and front edge view of the magnetic strip with a representation of the magnetic flux recorded therein.
FIG. 2 shows a diagram of the preferred embodiment of the present invention, dubbed a multi-card by the inventor, having a plastic substrate 3, on which is suitably mounted a programmable magnetic strip 4, an LCD display 5, a solar cell power source 6, including an electricity storage cell (not shown), an infrared emitter 7, and infrared sensor 8, and a key pad 9 consisting of 14 operator actuated switches. It will be appreciated that these switches may be capacitive type touch sensitive sensors or other types. It will be understood that the programmable magnetic strip 4 may also be of a type which may sense magnetic information or patterns, and thus may be used as an input or output device.
Programmable magnetic strip 4 is preferred to be operated to approximate, duplicate or replicate a magnetic pattern matching the particular need of the operator in response to the operator's commands or inputs to the card as will be described in more detail below.
In operation, the multi-card has stored in it several sets of data corresponding to account related information or patterns for different credit cards, identification cards and the like. Power for the operation of the device is provided by a solar cell, which power is stored in a storage battery. The battery is preferred to be replaceable with a charged battery for those applications where the solar cell does not receive enough light to operate the multi-card, however it is preferred that devices which make use of the multi-card provide sufficient illumination to the solar cell to power the device.
To operate the multi-card, the operator simply presses a given key, which may be a touch sensitive pad, which causes multi-card to activate and the display 5 to display which account is associated with that key. If the operator forgets which key is associated with a wanted account, he may simply operate all keys in sequence until the correct account is selected. It will be understood that it is also possible to provide only one key, with a different account called up for each press.
When each account is called, the magnetic data for that account is loaded into the magnetic strip 4, causing the magnetic strip to simulate the magnetic strip on the prior art type card by emulating, approximating, replicating or duplicating the magnetic pattern, depending on the accuracy required by the device reading the pattern. The control of the accuracy provided may be provided by the operator, or may be automatic in response to feedback (or lack thereof) by the device using the card. In this fashion, the multi-card may then be placed into a card reader or other device which reads the magnetic pattern from the magnetic strip to allow the holder access to the account, services or features associated with the stored data or pattern.
It will be recognized by one of ordinary skill in the art from the teachings herein that the invention allows access to numerous accounts, services, features, etc. with just one card, thereby eliminating the need to carry, store or retain numerous cards. Other features may be combined with the invention as well, or as the case may be the invention may be combined with other functions, examples including personal reminder and memory capability, calculator and clock or even telephone and television functions.
Other sequences of operation of the invention may be utilized as well. For example, the key pad may be used to enter a convenient select designator, for example a BC representing bank card or a PBC indicating personal bank card, or any other convenient select designator. The select designator will then cause the account identifier to be displayed on 5 and the proper pattern loaded into 4. In addition, the loading of pattern into 4 may be caused to occur only when another command is generated by the operator, or only upon or after insertion of the card in a device which uses it. These operations are considered to be novel features of the invention.
It will be understood by one of ordinary skill in the art that elements 3 and 5-9 are well known and commonly found and utilized in the industry and may be controlled by a microprocessor with their application and use in the preferred embodiment of the invention being within the capability of one of ordinary skill in the art.
FIG. 7 shows an top and side views of an alternate mechanical embodiment similar to FIG. 2. The mechanical embodiment of FIG. 7 has the advantage of allowing a larger space for the electronics while maintaining a thin cross section in the "card" area, thus allowing easier fabrication.
FIG. 3 shows a diagram of the multi-card and a supporting console which may be used to store information or patterns in the multi-card or recover information or patterns from the multicard, or another card. A control circuit 11, which is preferred to be a microprocessor such as an Intel 80C31 or which may have internal ROM, ram and nonvolatile ram as is known in the industry, is utilized to control and operate the various elements of the multi-card.
As an example the Intel 80C31 series microcontroller is well suited to the control task. When the 80C31 is coupled with a nonvolatile ram such as the Xicor X2444 available from Xicor, Inc. 1511 Buckeye Drive, Milpitas, Calif., a keypad such as can be easily constructed with the ITT Schadow KSA1M211 switch available from ITT Schadow Inc. 8081 Wallace Rd., Eden Prairie, Minn., and an LCD display such as the Optrex DMC20261NY-LY-B, available from 44160 Plymouth Oaks Blvd., Plymouth, Mich., the invention components may be readily constructed. A 16 keypad matrix in 4×4 form (not all 16 need be used) is preferably configured on the 8 P1 port connections, the LCD is preferably configured on the P0 data port under write control as addressed by the P2 data port and controlled by the /WR control. The input/output interface 14 is preferably provided via the TXD/RXD serial ports (alternate functions provided on the P3 port), and the nonvolatile ram is preferably configured directly to the /INT0, /INT1 and T0 pins of the P3 port. The program instructions to run the processor are preferably stored in an EPROM having data pins coupled to the P0 port and addressed by the P2 port under /RD read control as is commonly known in the industry. Intel provides a wealth of information on configuring, programming and operating this and many other processors, which information is available from Intel Corporation, 3065 Bowers Ave., Santa Clara, Calif.
The programmable magnetic strip 10 is preferred to contain multiple inductive coils to generate magnetic fields in response to current flowing therein, as will be described in more detail below. The connection of the processor of 11, be it an 80C31 or other type may be made directly via matrixing of the two connections of the individual coils in 10, for example as is commonly done to write (and read from) core type magnetic memory in the computer industry. Alternately, a large serial shift register array may be loaded with serial binary data under control of 11 with the array's output being enabled to a low impedance state from a high impedance state after loading. The binary data may thus cause the many parallel outputs, each of which is coupled to a coil, to source electrons into the coil, or sink electrons from the coil, providing that the other end of each coil is connected to a voltage source which is midway between the output's high and low logic level states. To achieve control over the current flow through the coils, multiple serial shift registers may be utilized, with several outputs being coupled to each coil through resistors or other current controlling circuits, the pattern of data in the several outputs controlling the current flow.
Several variations of the suggested elements of the preferred embodiment may be utilized as will be convenient to implement particular embodiments of the invention which may be configured to specific needs and applications, as will be apparent to one of ordinary skill in the art from the teachings herein.
The substrate 3 may be of any material on or to which the other elements may be suitably secured or attached, examples including the preferred PVC plastic, ceramic, metal and others. Display 5 which is used to provide messages to the user of the device may be of any electro optical type such as LCD, LED, CRT, incandescent, fluorescent, flip dot, etc. or may be of electro mechanical type such as beeper, buzzer, vibrator, etc., or may be eliminated in applications where it is not desired to convey messages to the user, or where messages are conveyed via other means. Such other means for example include via the device which reads the magnetic strip 4.
Power source 6 may be any well known power source, such as solar cell, battery, electric generator operating to convert motion to electricity, fuel cell, electromagnetic or electric field receiver, piezoelectric generator, etc. or any combination thereof.
Emitter 7 may be the preferred infrared LED, antenna, coil, transducer, or any other device capable of conveying information or patterns from the invention to outside devices, and receiver 8 is preferred to be a photo transistor but may also be any such apparatus or device capable of receiving information or patterns from outside devices to be used by the invention. Either or both of the emitter and receiver may be eliminated if the capability provided is not desired, or is otherwise provided for. For example, the sensing capability of 10 or the input capability of 13 may be utilized to provide the receiver 8 function and the display 12 may be utilized to provide the emitter function.
Touch sensitive key pad 9 may be capacitive, heat sensing, optical or mechanical switches, etc. or any device capable of receiving and coupling operator input to the invention. The operator interface 13 and its key pad 9 may also be eliminated if no operator interface is desired.
The control circuit operates with the programmable magnetic strip 10, examples include those corresponding to 4 of FIG. 2, to create a predetermined magnetic pattern which may be read by compatible reading devices, and may also operate in conjunction with 10 to sense magnetic patterns. Control circuit 11 also drives the LCD display 12, examples including associated with 5 of FIG. 2, to display messages to the operator and as signified by the dotted arrow on the control circuit 11 may also operate interactively with 12. Control circuit 14 operates interactively with the input/output interface 14, examples including those associated with 7 and 8 of FIG. 2, to communicate with the console. Control circuit 11 also operates interactively with operator interface 13, examples including those corresponding to 9 of FIG. 2, to allow operator input to the control circuit. Also shown in FIG. 3 is a power source 15, examples including those associated with 6 of FIG. 2, and which provides power for the operation of the multi-card. In the preferred embodiment, 15 includes a replaceable nickel cadmium battery and solar cell allowing the battery to be replaced and/or recharged. It is of course possible to use either replaceable or rechargeable power sources.
FIG. 3 includes a console comprised of programming circuitry 16 and card reader 17. In operation, the card reader may be operated to read information or patterns from a particular data storage medium, examples including the magnetic strip on a credit card. The information or patterns may be read as the actual data represented in any of its various forms, or may be read simply as the representation. With respect to reading a magnetic stripe, the reader may simply read the magnetic pattern without concern as to the data represented thereby, or may decode the magnetic pattern into the encoded (that is represented) data, or may decode the data to the unencoded (that is unprotected by security scrambling and the like) data as is convenient. In the preferred embodiment, the magnetic pattern is simply sensed at a high resolution by moving the magnetic strip over a magnetic sensor and generating a binary representation of the polarity of the magnetic field in response thereto. The resulting binary pattern corresponds to the magnetic polarity field, in the preferred embodiment at 0.001 inch increments, giving a linear "snapshot" of the magnetic pattern.
The binary representation is then coupled to the programming circuitry 16 (via 14) where an account identifier is associated therewith to later be displayed on the display 12 when the wanted corresponding magnetic pattern is recalled from the memory in the control circuit 11. While called an account identifier, there is no need that the pattern correspond in any way to an account, and may well correspond to anything. The account identifier may be thought up by the operator, may be chosen by the operator from a list or other source, or may be assigned without operator intervention, for example preprogrammed in the card which is read or in the control circuit 11. The input of the account identifier may be via 13 or 16 as is desired. It is however preferred that the operator may have some choice in the matter in order that an account identifier which is either convenient to or associated by the operator is used, and thus it is preferred that 16 contain a keyboard with which the operator may type in his desired identifier, and the desired key, key sequence or location associated therewith.
It is also preferred to associate a select designator with the binary representation, in order to allow the operator to utilize the select designator to call up a particular magnetic pattern. The select designator may be thought up by the operator, may be chosen by the operator from a list or other source, or may be assigned without operator intervention, for example preprogrammed in the card which is read or preprogrammed in the control circuit 11 at the time of manufacture or other time.
In operation, it is preferred that there be more than one method for the operator to call up a wanted pattern. One preferred way is for the operator to enter the select designator. This causes the account identifier to be displayed in 12. Alternatively, the operator may scroll through all the possible sets of data, viewing each account identifier as it appears until the desired one is called up, or may key in a more detailed pattern, to call up the desired account.
The magnetic pattern (or data represented thereby in some form) is then caused to be stored in the memory of 11 in a form which allows it to be associated with the identifier, and preferably also with some known input terminal or sequence of terminals of 9. In the preferred embodiment, the operator chooses an available key of 9 (for example the upper right) or other select designator, provides an account identifier, (for example BANK CARD) and the operator choices and data are stored in 11 in a fashion which associates them all. It is preferred that the data be stored in nonvolatile memory in order that it will be retained in the event that the power storage device of 15 is fully discharged or the control circuit is turned off, for example to save power.
It is preferred that by utilizing the foregoing programming procedure, the operator stores the magnetic pattern, account identifier and desired associated select designator in 11. Upon subsequent entry of the associated select designator, the control circuit 11 recalls the associated data corresponding to the magnetic pattern and the account identifier from memory. The account identifier is loaded in the display 12 to remind the operator what the data is associated with, and the magnetic pattern is caused to be replicated in 10 from the stored data. The replicated magnetic pattern in 10 may then be utilized to operate a card reading device to provide the operator access to the account, services, features or other conveniences associated therewith, and hence associated with the card which was read by 17.
It is of course desired to provide the capability of storing several such sets of associated data, identifier and key in the memory of 11, and it is further desirable to provide for the association of multiple select identifiers with a given set of data. By way of example, in this fashion, a set of data for generating a magnetic pattern for a company issued bank card may be called up by use of any of the select identifiers CC, or COCARD or COMPANY CARD, etc. and another set of data for a personal bank card may be called up by use of any of the select identifiers PC, PBC, etc.
FIG. 4 shows a diagram of the details of the magnetic strip 10 and control circuit 11, including individual electromagnet coils, one of which is shown as 21 and having electric circuit connections 22 and 23, and magnetic flux conducting material 20. It will be recognized that by passing an electric current through a given coil that a magnetic flux will be created across the associated gap in the magnetic flux conducting material 20 above the coil, such as is represented by 24. Furthermore, the flux for each coil will be largely contained in the gap corresponding to that coil by the magnetic flux conducting material. The polarity of the flux may of course be changed by changing the direction of current flow through the coil, and the intensity of the magnetic flux may be varied by varying the electric current through the coil. In this fashion, the original magnetic pattern which was read by reader 17 may be approximated, duplicated or replicated as required. While it may be desirable to cause the control circuit 11 to have the ability to vary the accuracy with which it stores the magnetic data or programs the magnetic strip, it will be recognized that this is not a requirement, and 11 may simply operate to a single given accuracy. It may also be noted that the material used for 20 may be of a type having a large magnetic memory or hysteresis so that once a magnetic pattern is generated in the material, the electric current through the coils may be turned off or reduced and the magnetic field will remain. Techniques which are used to write and read magnetic core type memory, as well as the materials used therefore, will be applicable to the generation of magnetic patterns for 10, and the technology used in the core industry may be easily adapted to be used in fabricating 10. It will also be recognized that other methods of creating magnetic patterns may be utilized as well, such as various chemical, thermal and optical methods which may be utilized to create magnetic flux patterns, or to alter existing flux patterns.
FIG. 5 shows a sectional diagram A--A of elements 20-23 of FIG. 4 and the preferred method of construction thereof. This method of construction is readily implemented with either photographic lithography and lamination techniques or with chemical vapor etching and deposition as are commonly utilized to fabricate miniature electronic circuits. Other construction methods may be utilized as well.
Element 18 is a substrate material, examples including plastic or ceramic, on which the magnetic coils 21 may be built. A conductive layer 19 is formed on the substrate in a predetermined pattern to make up the bottom half of the coils 21. This layer may be created by depositing or printing a continuous metallic film and then etching away all but the desired conductive paths, or by photographically printing the conductive paths. Next, the magnetic material 20 is formed on top of the bottom conductive paths. Preferable the magnetic material is an electrically non-conductive or low conductive material, but if it is conductive, an insulating layer may first be deposited to prevent it from shorting out the top and bottom conductive paths. After the magnetic material is formed the top electrically conductive layer is formed thereover using the same process as for the bottom, thus completing the coils 21. Finally, conductive wires or circuits 22 and 23 are bonded to the coils for connection to 11, and the entire magnetic strip is provided with an environmentally insulating covering if desired to shield from moisture, corrosion, etc. By utilization of this method, it will be seen that very low manufacturing cost and small size may be obtained.
It will also be understood that the linear array of coils is given by way of example with respect to the preferred embodiment and may be arranged in other than a linear fashion, for example in circular or three dimensional patterns. It will also be understood that the magnetic coils may be replaced with LEDs to create emitted light patterns, or by LCD elements to create reflected or transmitted light patterns, or by any other type of energy radiator, absorber or deflector in order that the invention may be practiced with virtually any sort of emitted, absorbed or deflected pattern.
It will be recognized that while the coils may be utilized to generate a magnetic pattern, they may also be utilized to sense a magnetic pattern. While some motion is required to generate an electric current in the coils, this motion may be supplied by the user. In addition, magneto restrictive materials may also be adopted to allow sensing of magnetic patterns without motion. One of ordinary skill in the art will be able to construct such a device and practice the invention from the teachings of the preferred embodiment given herein without undue experimentation or further invention. It will also be recognized that it will be possible to have magnetic strip 10 sense the magnetic pattern on another magnetic strip directly, removing the need for card reader 17. It would also be possible to incorporate the programming circuitry 16 in the control circuit 11, thus completely eliminating the need for the console of FIG. 3. Once the console is eliminated, the input/output interface 14 may also be eliminated.
One skilled in the art will also recognize that an inexpensive version of the invention may be constructed of simply a programmable magnetic strip 10 which can both read and simulate a magnetic pattern, a control circuit 11, an elementary operator interface 13 and a power source 15.
Alternatively, instead of a magnetic strip 10 capable of reading, several preprogrammed magnetic patterns may be programmed in control circuit 11 upon manufacture, either by storage of the magnetic patterns, storage of data which may create the magnetic patterns or storage of an algorithm or method by which the magnetic pattern may be created in 10 under control of 11. In such a system, only elements 11 and 10 are absolutely required since it would be possible for 11 receive commands from the reading device via 10, or to simply try all stored patterns in 10 upon excitation or connection of the power source 15.
While the preferred embodiment of the invention has been given by way of example with respect to credit cards having magnetic strips, it will be recognized that the invention may very well be adapted for use with other methods of storage and storage medium. Examples include, simulating two or more dimension patterns. Optical devices which record data on film in two or more dimensions may be replaced by liquid crystal or other optical displays which simulate the patterns recorded on the film. Holographic recordings may also be simulated by LCD or other optical displays. Mechanical devices may be replaced by electromechanical devices in which mechanical dimensions are adjusted via solenoids, motors, piezoelectric cells or the like. Keys are an excellent example of a device which may be replaced by a battery of such adjustable devices.
In FIG. 6 for example, the device of FIG. 3 may be utilized in conjunction with micro machines in order to create an adjustable key in which the operator selects an identifier corresponding to the particular lock which he wishes to unlock. The device uses electromagnetically driven micromotors and worm screws to adjust the serrated edge on the key to fit the lock. A sectional view of the device is shown in which a standard key blank 25 is machined to couple to a bank of micro motors or solenoids 26, each of which is connected via a worm screw to a flexible shaft or wire which extends to the serrated edge of the key.
By way of example, micromotor 27 is coupled to flexible shaft 28 which passes through a hollow portion of the key blank 25 to the serrated edge where it protrudes through the blank at 29. Individual channels may be micromachined for the flexible shafts, or the shafts may simply be sized to fill the slot in the key blank, or bundled together to prevent lateral displacement which would affect the protrusion distance from the edge of the key blank at 29. The micromotor 27, via the screw, adjusts the position of the end of 28 to thereby control the length of protrusion of the other end at 29, thus adjusting the depth of the serration at that point. All of the micromotors in the bank 26 are coupled to the control circuit 11 of FIG. 3 by a suitable coupling. In this fashion, the key may be adjusted to fit different locks as desired by the operator. In this example, card reader 17 may be replaced with a key reader in order that the serration pattern of precut keys may be read into 11 and stored, along with account identifiers, select designators, etc. as previously described.
In view of continuing development of micro machines on silicon wafers by use of semiconductor fabrication techniques, it is envisioned that it will be possible to manufacture both electro mechanical components such as solenoids and the corresponding electrical control circuitry all on the same semiconductor substrate. In this fashion, it would be possible to manufacture the invention of FIG. 6, including the necessary control circuitry of FIG. 3 entirely with existing semiconductor fabrication technology.
It would also be convenient to replace the electronic storage of different patterns with a mechanical or other storage of patterns, for example with respect to the key of FIG. 6 on a rotating cam shaft, shown as 27 of the inset, which would be rotated to adjust the height of spring loaded pins on the key, the springs holding the pins against the cams. While the configuration of the inset would require a fairly wide key, the camshaft could also be located entirely within the handle of the key and be coupled to the spring loaded pins via flexible shafts or wires 28 as with the micromotor actuator 26. The account identifiers or select identifiers can be engraved directly on the end of the shaft. It will be understood that the flexible shafts may be arranged in other than a linear fashion, for example in circular or three dimensional patterns.
The invention described herein by way of explanation of the preferred embodiment may be practiced with numerous changes in the arrangement, structure and combination of the individual elements, as well as with substitution of equivalent functions and circuits for the elements in order to optimize the invention for a particular application, all without departing from the scope and spirit of the invention as hereinafter claimed. | The apparatus and method described herein provides for creating multiple spatial patterns, such as magnetic patterns on credit cards. The invention includes storage of information from which patterns may be created, a pattern creation device for creating the spatial patterns, and control whereby the information which is stored is selectively utilized to cause the pattern creation. This allows multiple desired patterns to be simulated, allowing convenient replacement of a number of separate pattern carrying devices. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Ser. No. 61/374,213 filed on Aug. 16, 2010, U.S. Ser. No. 13/023,467 filed on Feb. 8, 2011 and Republic of China Patent Application No. 099104551 filed on Feb. 12, 2010, commonly assigned, and hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus and method for purifying materials. More particularly, the present invention relates to a method and system for purifying metallurgical silicon fields to produce raw materials suitable for manufacturing single crystal silicon ingots and poly crystal silicon ingots for solar cells at a lower cost. Although the above has been described in terms of purifying silicon, it can be applied to other applications.
Conventional polysilicon silicon material used for manufacturing solar cells is often produced by the so-called Siemens process. Such process is well established, stable, and produces silicon with certain quality for manufacturing solar cells. The Siemens process, however, has limitations. That is, the Siemens' process, due to the nature of its manufacturing process, is difficult to adjust and has failed to meet the dramatic increase in demand and the need for lower prices over the past few years. In addition, it involves use of poisonous raw materials such as HCl and SiHCl 3 during the manufacturing process and produces a poisonous by-product, SiCl 4 . These materials are also highly explosive. The Siemens process is also dangerous and not environmentally friendly.
Alternatively, silicon purification methods that use metallurgy have been proposed. Such purification methods, however, have limitations. That is, such methods have not been able to achieve production scale. Certain other efforts have been achieved using metallurgy techniques. Unfortunately, the ability to scale of the equipment for such techniques is enormous, and thus the production costs are still high. These and other limitations may be overcome by the present techniques described throughout the present specification and more particularly below.
From the above, it is seen that improved techniques for producing silicon are highly desired.
SUMMARY OF THE INVENTION
The present invention relates to an apparatus and method for purifying materials. More particularly, the present invention relates to a method and system for purifying metallurgical silicon fields to produce raw materials suitable for manufacturing single crystal silicon ingots and poly crystal silicon ingots for solar cells at a lower cost. Although the above has been described in terms of purifying silicon, it can be applied to other applications.
The manufacturing methods mentioned above produce silicon with quality high enough for solar cells. But with increasing demands for cleaner and more flexible production, lower cost, and mass production capability, the conventional method has limitations. Depending upon the embodiment, one or more of these limitations may be overcome.
In a specific embodiment, the present invention provides a system for forming high quality silicon material, e.g., polysilicon. In a specific embodiment, the melted material comprises a silicon material and an impurity, e.g., phosphorous species. The system includes a crucible having an interior region. In a specific embodiment, the crucible is made of a suitable material such as a quartz material or others. The quartz material is capable of withstanding a temperature of at least 1400 Degrees Celsius for processing silicon. In a specific embodiment, the crucible is configured in an upright position and has an open region to expose a melted material. In a specific embodiment, the present system has an energy source. Such energy source may be an arc heater or other suitable heating device, including multiple heating devices, which may be the same or different. The arc heater is configured above the open region and spaced by a gap between the exposed melted material and a muzzle region of the arc heater to cause formation of a determined temperature profile within a vicinity of a center region of the exposed melted material while maintaining outer regions of the melted material at a temperature below a melting point of the quartz material of the crucible. In a specific embodiment, the system produces a melted material comprising a resulting phosphorous species of 0.1 ppm and less, which is purified silicon.
In a specific embodiment, the present invention provides a method for forming high quality silicon material, e.g., polysilicon. The method includes transferring a raw silicon material in a crucible having an interior region. The crucible is made of a quartz or other suitable material, which is capable of withstanding a temperature of at least 1400 Degrees Celsius. The method includes subjecting the raw silicon material in the crucible to thermal energy to cause the raw silicon material to be melted into a liquid state to form a melted material at a temperature of less than about 1400 Degrees Celsius. Preferably, the melted material has an exposed region bounded by the interior region of the crucible. The method also includes subjecting an exposed inner region of the melted material to an energy source comprising an arc heater configured above the exposed region and spaced by a gap between the exposed region and a muzzle region of the arc heater to cause formation of determined temperature profile within a vicinity of an inner region of the exposed melted material while maintaining outer regions of the melted material at a temperature below a melting point of the quartz material of the crucible. Preferably, the method removes one or more impurities from the melted material to form a higher purity silicon material in the crucible.
In a specific embodiment, the arc heater is a plasma gun configured to emit an excited argon species to cause thermal transfer to a portion of the melted material. In a specific embodiment, the arc heater is configured to subject a selected portion of the exposed region of the melted material. The arc heater is configured with a thermal transfer device to cause cooling of the arc heater. In a specific embodiment, the arc heater is capable of being ignited by a source. Preferably, the arc heater comprises a power rating of 20 kWatt and greater and capable of being pulsed according to a duty cycle of about 30%˜50%, and others. For example: 30% duty cycle means 30% on, then 70% off, which is interpreted by one of ordinary skill in the art. In a specific embodiment, the muzzle region has a maximum dimension of about 0.5 centimeters to about 2 centimeters. Of course, there can be other variations, modifications, and alternatives.
In a specific embodiment, the temperature profile is determined to achieve a certain result. That is the temperature profile is a maximum temperature profile greater than about 3000 Degrees to cause removal of phosphorous entities from the melted material. In a preferred embodiment, such temperature has been important to remove any phosphorous impurities and/or entities from a silicon material melt. In a specific embodiment, the melted material within the crucible is characterized by a convective flow caused by a temperature gradient formed by at least the maximum temperature profile and lower temperatures within a vicinity of edges of the melted material. In a specific embodiment, the convective flow causes a mixing within the melted material. In a preferred embodiment, the flow is also turbulent to facilitate mixing within the melted material.
In a preferred embodiment, the system and method also have a nozzle region configured to output argon gas to cause a dimple region within a vicinity of the center region of the melted material. In one or more embodiments, the nozzle region is a plurality of nozzles or the like. In a specific embodiment, the dimple region provides an increased surface region for a plume to interact with the melted material; wherein the dimple region has a depth of at least one centimeter and greater. Preferably, the increased surface region is at least three times greater than a surface region without the dimple region or more preferably, the increased surface region is at least five times greater than a surface region without the dimple region. As an example of silicon, the melted material comprises a viscosity of 0.7 Pascal-second, which may be slightly more or less. In a preferred embodiment, the argon gas comprises a flow rate of 5 l/min to 20 l/min. In a specific embodiment, the gas impinging on the melted material forms the dimple region that is characterized by a plurality of recessed regions each of which is separated by an elevated region. In a specific embodiment, the nozzle region coupled to the argon gas source is made of a ceramic material. Preferably, the argon gas source is operable independent from operation of energy of the arc tube. In a preferred embodiment, the argon gas source is 99.99% purity and greater. In other embodiments, other suitable gases that are non-reactive may be used. Of course, there can be other variations, modifications, and alternatives.
In a preferred embodiment, the present system and method use a cover gas or pressing gas to enclose a substantial portion of the melted material within the crucible. That is, the crucible is subject to a cover gas to maintain the melted material within the crucible. In a preferred embodiment, the crucible is subject to an argon containing cover gas or other suitable inert gas or gases to maintain the melted material within the crucible. Preferably, the cover gas is suitable to maintain the melted material free from oxidation or other undesirable conditions. The cover gas is provided within a chamber and/or housing enclosing the crucible. Of course, there can be other variations, modifications, and alternatives.
In a preferred embodiment, the system and method also include a carrier gas configured to cause a portion of evaporated melted material to return to the melted material. In a specific embodiment, the carrier gas can be argon or other inert gas, which is suitable to return any evaporated melted material consisting of silicon entities back into the melted material. In a specific embodiment, the system includes a plurality of surface regions configured to cause a substantial portion of a phosphorus species to be exhausted while returning a substantial portion of silicon species into the melted material. Preferably, the surface regions comprise a plurality of fin regions configured to cause a substantial portion of a phosphorus species to be exhausted while returning a substantial portion of silicon species into the melted material. Of course, there can be other variations, modifications, and alternatives.
In other embodiments, the present invention includes an apparatus for purifying metallurgical silicon that overcomes limitations of conventional techniques. In a specific embodiment, the present method and system modify a conventional single crystal silicon puller apparatus, which usually includes a vessel, a crucible, a crucible support and a heater. By implementing at least one of the following means in the existing apparatus, purification of metallurgical silicon is performed using one, some or all of the devices simultaneously: an independent injecting device provided above the crucible for providing plasma, gases and chemicals required for purifying in a high-speed jet flow to the surface of a silicon melt, and forming a dimple on the surface of the silicon melt by its supplying tubes, and in cooperation with a temperature profile across the silicon melt due to a temperature gradient, facilitating heat circulation and increasing the circulation inversion radius, as well as increasing the contact area between the purifying gases and chemicals and the silicon melt, thereby increasing purification efficiency;
a guiding element with fins thereon, provided above the silicon melt in the crucible at an appropriate location with respect to the crucible and the supplying tubes for supplying the purifying gases and chemicals, for guiding damped gas flow rising from the surface of the silicon melt as a result of heating of the silicon melt back to the surface of the silicon melt, so that the damped gases effectively contact the silicon melt, wherein the distance between the guiding element and the surface of the silicon melt, the distance between the fins and the silicon melt, and the distance between the interior circumference of the crucible and the fins are critical; a manipulating device provided underneath the vessel for vertically and horizontally shifting and rotating the crucible with respect to the heater to adjust the solidus-liquidus interface to obtain one-directional cooling purification without the need for temperature segregation coefficient management of the concentration of remaining impurities in the silicon melt with respect to the solidus-liquidus line, therefore allowing effective backflow of the damped gases and controlling the form of the dimple created by the jet flow from the injecting device on the surface of the silicon melt by adjusting the distance between the crucible and the guiding element, wherein a set of valves capable of horizontal shifting is further provided in the manipulating device in order to reduce reactions of carbon parts with oxygen when the crucible is taken out or inserted into the vessel by opening/closing the vessel; and a vacuum pump provided to regulate the pressure or degree of vacuum inside the vessel and to accommodate evaporating conditions for various impurities.
According to a specific embodiment, the present technique overcomes some or all of these limitations by adding simple structures such as an independent gas and chemical injecting device, a crucible shifting manipulating device, a gas flow guiding element, and a vacuum pump to regulate the pressure inside the vessel, so that with these small modifications, purification efficiency can be improved. Meanwhile, the apparatus is simple, is easy to maintain, is with small modifications to an existing single crystal silicon puller apparatus, and has a short building time; therefore, the cost can be reduced, and mass production is possible. In addition, the apparatus of the present technique does not use poisonous raw materials and produces no poisonous by-products, while ensuring the safety of the purification process.
According to a specific embodiment, the present invention provides an apparatus for purifying metallurgical silicon obtained by modifying an existing single crystal silicon puller apparatus including a vessel, a crucible, a crucible support and a heater. The apparatus includes one, some, or all of the following devices for the purification of metallurgical silicon: an independent injecting device above the crucible for providing plasma, gases and chemicals required for purifying in a high-speed jet flow to the surface of a silicon melt; a guiding element above the silicon melt in the crucible at an appropriate location for guiding gas coming from the surface of the silicon melt back to the surface of the silicon melt; a manipulating device underneath the vessel for vertically and horizontally shifting and rotating the crucible with respect to the heater and the guiding element to obtain optimum purification efficiency; and a vacuum pump to regulate the pressure or degree of vacuum inside the vessel and to accommodate evaporating conditions for various impurities.
Many benefits are achieved by way of the present invention over conventional techniques. For example, the present technique provides an easy to use process that relies upon conventional technology. In some embodiments, the method provides highly purified silicon material using a modular approach. In preferred embodiments, the present method and system uses one or more of (1) nozzle for gas in making dimple region(s) in the melted material; (2) cover gas or environment for maintaining the melted material; and (3) carrier gas or environment for returning vaporized melted material back into the melt. Additionally, the method provides a process and system that are compatible with conventional process technology without substantial modifications to conventional equipment and processes. Depending upon the embodiment, one or more of these benefits may be achieved. These and other benefits will be described in more throughout the present specification and more particularly below.
Various additional objects, features and advantages of the present invention can be more fully appreciated with reference to the detailed description and accompanying drawings that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein:
FIG. 1 is a cross-sectional diagram depicting a simplified traditional apparatus for growing single crystal silicon ingots.
FIG. 2 is a cross-sectional diagram depicting a first embodiment of a modified apparatus of the present invention.
FIG. 3 is a cross-sectional diagram depicting a second embodiment of a modified apparatus of the present invention for easy transportation of a crucible.
FIG. 4 is a cross-sectional diagram depicting inserting/removing the crucible into/from the vessel of FIG. 3 .
FIG. 5 is a cross-sectional diagram depicting the end of a tube for a purifying material supplying system of the present invention.
FIG. 6 (including 6 A and 6 B) is a cross-sectional diagram depicting a plurality of tubes for a purifying material supplying system of the present invention.
FIG. 7 is a cross-sectional diagram depicting a guiding element of the present invention.
FIG. 8 is a cross-sectional diagram depicting gas flow of a plasma arc heater in an apparatus of the present invention.
FIG. 9 is a schematic diagram illustrating a dimple and circulation of a silicon melt caused by a plasma arc heater and high-pressure gases of the present invention.
FIG. 10 is a schematic diagram illustrating the positional relationship of the injecting device and guiding element inside an apparatus of the present invention.
FIG. 11 is a schematic diagram illustrating arrangements of a plurality of arc heaters of the present invention.
FIG. 12 is a schematic diagram illustrating positions of a plurality of injecting device with respect to a crucible of the present invention.
FIG. 13 (including 13 A and 13 B) is a schematic diagram illustrating a dimple region on a center of the surface of a silicon melt caused by a plurality of plasma arc heaters of the present invention.
FIG. 14 is a simplified diagram of a pulling apparatus according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
The present invention relates to an apparatus and method for purifying materials. More particularly, the present invention relates to a method and system for purifying metallurgical silicon fields to produce raw materials suitable for manufacturing single crystal silicon ingots and poly crystal silicon ingots for solar cells at a lower cost. Although the above has been described in terms of purifying silicon, it can be applied to other applications.
The implementations of the present invention are described using the embodiments below.
FIG. 1 is a cross-sectional diagram depicting a simplified apparatus typical for growing single crystal silicon ingot. This diagram is merely an example, which should not unduly limit the scope of the claims herein. One of ordinary skill in the art would recognize other variations, modifications, and alternatives. In the diagram, reference number 1 indicates a vessel, 2 a crucible support, 3 a crucible manipulating device, 4 a heater, and 5 a crucible. Quartz crucible 5 in vessel 1 is supported by crucible support 2 made of low-density thermo material to prevent cracking of crucible 5 due to thermal creep during the silicon purification process. Crucible 5 is placed inside heater 4 , which radiates heat and produces a thermal field in vessel 1 to melt the silicon raw material in crucible 5 , thereby producing silicon melt. The silicon melt absorbs the heat radiated from heater 4 and dissipates heat from its surface or propagates heat to a growing ingot (not shown) via the solidus-liquidus interface and dissipates heat from the ingot surface, producing a silicon growing phenomenon. Crucible manipulating device 3 shifts crucible 5 up or down to assist the growing of the silicon. This is because, during silicon growth, the ingot slowly rotates upwards while the silicon melt surface descends, in order to keep a constant level of the liquid surface as well as to maintain the heating of the silicon material at the solidus-liquidus interface; crucible 5 has to be slowly raised to ensure stability of the silicon growing process.
It should be noted that in order to avoid oxidation of silicon at high temperature, the vessel is usually operated in a inert argon (Ar) gas atmosphere, wherein Ar gas can be fed through the top of the vessel to facilitate purification through reaction of Ar damped gas and the silicon melt.
In a preferred embodiment, the present system and method use a cover gas or pressing gas to enclose a substantial portion of the melted material within the crucible. That is, the crucible is subject to a cover gas to maintain the melted material within the crucible.
In a preferred embodiment, the crucible is subject to an argon containing cover gas or other suitable inert gas or gases to maintain the melted material within the crucible. Preferably, the cover gas is suitable to maintain the melted material free from oxidation or other undesirable conditions. The cover gas is provided within a chamber and/or housing enclosing the crucible. Of course, there can be other variations, modifications, and alternatives.
FIG. 2 is a diagram depicting a first embodiment of a metallurgical silicon purification apparatus modified from a conventional crystal puller. This diagram is merely an example, which should not unduly limit the scope of the claims herein. One of ordinary skill in the art would recognize other variations, modifications, and alternatives. In the diagram, reference numeral 10 indicates a vessel, 10 a the upper portion of the vessel, 10 b the vessel body, 11 a heater, 12 a decompression tube, 15 an exhaustion passage controlling cap, 20 a crucible, 30 a crucible manipulating device, 61 a chemical and gas supply tube, 62 a high-pressure gas supplying tube, 70 a gas flow guiding element, and 100 a silicon melt.
Vessel 10 consists of upper portion 10 a and vessel body 10 b . Above the surface of silicon melt 100 is an independent injecting device consisting of a chemical and gas supply tube 61 and a high-pressure gas supply tube 62 . Through supply tube 61 , chemicals and gases required for purification, such as soluble compounds of calcium (Ca), silicon (Si) and magnesium (Mg), hydrogen (H 2 ) gas or oxygen (O 2 ) gas, are delivered to the surface of the silicon melt 100 . Meanwhile, through high-pressure gas supply tube 62 , high-pressure, damped gas mixtures, such as water steam (H 2 O) or Ar gas, are delivered to the center of the surface of the silicon melt 100 via the high-pressure jet flow, thereby forming a dimple 90 at the surface of silicon melt 100 (see FIG. 9 ), and in conjunction with a temperature gradient within silicon melt 100 in crucible 20 , heat circulation and/or mass convection can be achieved. The jet flow not only facilitates mixing of silicon melt 100 in crucible 20 , but also increases the contact areas between the chemicals/gases and silicon melt 100 , thus improving the efficiency of the purification process.
In addition, guiding element 70 is provided above silicon melt 100 in crucible 20 at an appropriate location and distance with respect to crucible 20 and supplying tubes 61 and 62 . Through guiding element 70 , hot gas rising from the surface of silicon melt 100 is guided back to the surface of silicon melt 100 , allowing effective contact of the damped gas with silicon melt 100 , thus increasing the efficiency of the purification process. Guiding element 70 is further discussed below.
In a preferred embodiment, the system includes guiding element along with a carrier gas configured to cause a portion of evaporated melted material to return to the melted material. In a specific embodiment, the carrier gas can be argon or other inert gas, which is suitable to return any evaporated melted material consisting of silicon entities back into the melted material. In a specific embodiment, the system includes a plurality of surface regions configured to cause a substantial portion of a phosphorus species to be exhausted while returning a substantial portion of silicon species into the melted material. Preferably, the surface regions comprise a plurality of fin regions configured to cause a substantial portion of a phosphorus species to be exhausted while returning a substantial portion of silicon species into the melted material. Of course, there can be other variations, modifications, and alternatives.
In addition, in order to prevent oxidation of the silicon at high temperature and superheating of the silicon melt, the degree of vacuum inside vessel 10 is changed to accommodate evaporating conditions for various impurities contained in the raw silicon, so as to ensure a safe metallurgical silicon purification process. Specifically, a vacuum pump (not shown) and a gas flow valve (not shown) can be used to control the gas and gas flow in vessel 10 , wherein the pump regulates pressure via decompression tube 12 , which avoids any danger caused by pressure rising due to a constant supply of water steam (purifying material), thereby providing safe and stable metallurgical silicon purification process conditions.
FIGS. 3 and 4 are diagrams depicting a second embodiment of the metallurgical silicon purification apparatus modified from the conventional puller. In the diagram, reference numeral 10 indicates a vessel, 11 a heater, 12 a decompression tube, 13 a set of valves and/or port or load locks, 14 a set of valve operating arms, 15 an exhaustion passage controlling cap, 20 a crucible, 30 a crucible manipulating device, 31 a crucible manipulating device base, 32 a crucible manipulating device shifting shaft, 33 a crucible manipulating device motor, 40 a crucible transporting device, 41 a crucible conveyer belt, 50 a plasma arc heater, 60 a purifying material supplying system, 61 a chemical and gas supply tube, 62 a high-pressure gas supply tube, 70 a gas flow guiding element, and 100 a silicon melt.
Above the surface of silicon melt 100 is an independent injecting device consisting of chemical and gas supply tube 61 and high-pressure gas supply tube 62 . Through supply tube 61 , chemicals and gases required for purification, such as soluble compounds of calcium (Ca), silicon (Si) and magnesium (Mg), hydrogen (H 2 ) gas or oxygen (O 2 ) gas, are provided to the surface of silicon melt 100 . Meanwhile, through high-pressure gas supplying tube 62 , high-pressure damped gas mixtures, such as water steam (H 2 O) or Ar gas, are provided to the center of the surface of silicon melt 100 via the high-pressure jet flow, thereby forming a dimple 90 at the surface of silicon melt 100 (see FIG. 9 ), which, in conjunction with the temperature gradient within silicon melt 100 in crucible 20 , allows heat circulation and/or convection to be achieved. The jet flow not only facilitates mixing of silicon melt 100 in crucible 20 , but also expands the contact areas between the chemicals/gases and silicon melt 100 , thus improving the efficiency of the purification process. In addition, plasma arc heater 50 is provided above silicon melt 100 . The plasma arc heater 50 , forming an independent injecting device in conjunction with purifying material supplying system 60 , intermittently and locally emits the plasma toward the surface of silicon melt 100 in crucible 20 . This creates a reproducible temperature profile across silicon melt 100 . Meanwhile, oxygen (O 2 ) gas from high-pressure gas supplying tube 62 is provided toward the burning hydrogen (H 2 ) supplied by plasma arc heater 50 and into the center of the surface of silicon melt 100 in crucible 20 , forming water steam (H 2 O) via hydrogen burning. The water steam is further propagated into silicon melt 100 through the force of the high-pressure oxygen jet flow, effectively providing water steam required for silicon purification to silicon melt 100 .
In addition, in the second embodiment, a crucible manipulating device 30 is provided underneath vessel 10 to provide for raising/lowering, rotating and horizontal shifting. Crucible manipulating device 30 includes crucible manipulating device base 31 , crucible manipulating device shifting shaft 32 , and crucible manipulating device motor 33 . Since the present invention does not need a seed ingot for silicon growth, during the purifying process, the surface level of silicon melt 100 in crucible 20 does not descend. Through crucible manipulating device 30 , not only can the vertical movements of crucible 20 inside vessel 10 be controlled in order to install or remove crucible 20 , but crucible 20 at the end of the silicon purification process can be transported in cooperation with crucible transporting device 40 and crucible conveyer belt 41 . Moreover, the vertical movements and the rotation of crucible 20 can be controlled by crucible manipulating device 30 , so as to adjust the solidus-liquidus interface of silicon melt 100 with respect to the location of heater 11 , so as to achieve one-directional cooling purification associated with Segregation Theory, without the need for temperature segregation coefficient management of the concentration of remaining impurities in silicon melt 100 with respect to the solidus-liquidus line. In addition to adjusting the solidus-liquidus interface of silicon melt 100 with respect to the location of heater 11 for silicon purification by crucible manipulating device 30 , the distance between crucible 20 and guiding element 70 can also be controlled by crucible manipulating device 30 , so that damped gases from the surface can be effectively directed back to silicon melt 100 to facilitate the supply of water for purification. Meanwhile, by controlling the distance, the form of dimple 90 (see FIG. 9 ) on the surface of silicon melt 100 caused by direct impact of the jet flow from the injecting device can be controlled. Furthermore, referring to FIGS. 3 and 4 , besides the crucible manipulating device 30 , a set of valves 13 that can be horizontally closed or opened, and which are controlled by a set of valve operating arms 14 capable of horizontal shifting, is provided beneath vessel 10 . When installing/removing crucible 20 into/from vessel 10 , the valve 13 is opened and closed horizontally to reduce the reaction of carbon products in the vessel with oxygen, which would affect the purification response of silicon melt 100 .
In addition, guiding element 70 is provided above silicon melt 100 in crucible 20 at an appropriate location with respect to crucible 20 and supply tubes 61 and 62 . Through guiding element 70 , hot air flow from the purifying gas flow provided to the surface of silicon melt 100 is guided back to the surface of silicon melt 100 , allowing effective contact of the damped gas with silicon melt 100 , thus increasing the efficiency of the purification process.
In addition, in order to prevent oxidation of the silicon at high temperature, vessel 10 has to be kept at a certain degree of vacuum. Specifically, a vacuum pump (not shown) and a gas flow valve (not shown) can be used to control the gas and gas flow in vessel 10 , wherein the pump regulates pressure via decompression tube 12 , which avoids any danger caused by pressure rising due to constant supply of water steam (purifying material), therefore providing safe and stable metallurgical silicon purification process conditions.
FIG. 5 is a schematic diagram depicting the tube end of purifying material supply system 60 of the present invention described in FIGS. 2 , 3 , and 4 . For the purpose of supplying high pressure damped gas mixtures so as to form a dimple 90 on the center of the surface of silicon melt 100 that expands the contact area and contact time of the purifying materials with silicon melt 100 , and enhancing the mixing of silicon melt 100 in crucible 20 for purification, the tube of purifying material supplying system 60 is designed to have a converging cone shape to increase the injecting pressure and flow rate. The material of this cone-shaped tube should be carefully selected to reduce loss when used for supplying chemicals and gases and as a heat source. To this end, the tube is preferably coated by a material such as quartz.
FIG. 6 is a schematic diagram depicting an implementation of independent purifying material supplying system 60 of the present invention consisting of chemical and gas supply tube 61 and high-pressure gas supply tube 62 described in FIGS. 2 , 3 , and 4 . FIG. 6 shows a design of concentric double tubes for providing different combinations of purifying materials (e.g., chemicals, gases, and soluble chemicals), including an outer tube a and an inner tube b. Reference letters/numerals a 0 and b 0 indicate the outlets of outer tube a and inner tube b, respectively. However, the present invention is not limited to these, but can have three or more tubes, as long as they provide different combinations of purifying materials to the surface of the silicon melt.
FIGS. 6(A) and 6(B) are cross-sectional diagrams depicting implementations of multi-tube designs for supplying purifying materials to the surface of silicon melt 100 . As shown in FIG. 6(A) , the inner tube protrudes from the outer tube, wherein outlet b 1 of the inner tube supplies high-pressure damped gases (e.g., Ar) and/or water, while outlet a 1 of the outer tube supplies Ar gas. Through such a design, the high-pressure damped gases and/or water may pass through the surface of the silicon melt via the center of dimple 90 (see FIG. 9 ), effectively delivering damped gases and/or water required for silicon purification into silicon melt 100 in crucible 20 . As shown in FIG. 6(B) , the inner tube is shorter than the outer tube, and outlet a 2 of the outer tube supplies H 2 gas for reacting with O 2 to form water, while outlet b 2 of the inner tube supplies O 2 necessary for forming water when reacting with the burning hydrogen gas. Since the inner tube is shorter than the outer tube, H 2 provided by outlet a 2 of the outer tube can reach the surface of silicon melt 100 through diffusion and burn due to high temperature, and if O 2 is provided from outlet b 2 of the inner tube b 2 towards the center of the burning H 2 , water steam is produced. This water steam and a portion of the non-reacted free oxygen are effectively brought to the surface of the silicon melt 100 for purification.
FIG. 7 is a schematic diagram depicting a design for gas flow guiding element 70 of the present invention. As described above, guiding element 70 is positioned at an appropriate distance and location with respect to silicon melt 100 in crucible 20 , taking into consideration plasma arc heater 50 and purifying material supplying system 60 . The guiding element 70 redirects rising hot air back to the surface of silicon melt 100 , allowing effective contact of the damped gas with silicon melt 100 , thus increasing the efficiency of the purification process. Guiding element 70 includes a body 74 and several fins 71 , 72 and 73 extending from the lower edge of body 74 .
FIG. 8 is a schematic diagram depicting the flow of the rising hot and damped gases. When plasma arc heater 50 irradiates silicon melt 100 in crucible 20 , the temperature of silicon melt 100 rises and generates a rising hot and damped gas flow (indicated by dashed lines), which diffuses above the surface of silicon melt 100 in crucible 20 .
Also, FIG. 10 shows the distances and locations of guiding element 70 with respect to crucible 20 and the surface of silicon melt 100 , and their relative relationship with the rising hot and damped gas flow. The following distances and locations are obtained from actual experiments performed by the inventors, which are not to be construed as limiting the present invention.
As shown in FIG. 10 , reference numeral 11 indicates a heater, 50 a plasma arc heater, 60 a purifying material supply system, 61 a chemical and gas supply tube, 62 a high-pressure gas supply tube, 70 a gas flow guiding element, 71 and 72 fins, 20 a crucible, 100 a silicon melt, h 1 the distance between the plasma arc heater outlet and the surface of the silicon melt, h 2 the distance between fin 71 of guiding element 70 and the surface of silicon melt 100 , h 3 the length of longest fin 71 , h 4 the distance from gas supplying tube 61 to the plasma arc heater 50 outlet, s 1 the distance between the bore of guiding element 70 to the plasma arc heater 50 , s 2 the distance from the plasma arc heater 50 to inner fin 72 , and s 3 the interval between fins 71 and 72 . Distance h 4 is dependent on the jet force of purifying material supplying system 60 and the supplied amount (V) of the gas flow through guiding element 70 .
Based on the experimental results, when the supplied amount (V) is 100˜800 L/hour, distance h 4 is 10 cm, which is the maximum value.
For distance h 1 , it can be understood from the experimental results that when distance h 1 reaches 5 cm, the results are best. A suitable range is from 1 cm to 18 cm.
For distance s 1 , it can be understood from the experimental results that this distance s 1 should be as short as possible to accelerate the rate at which the gas flows through. From the experimental results, in the case that the chemical and gas supplying tube 61 and the high-pressure gas supplying tube 62 are lowered to the level of the lower edge of guiding element 70 , distance s 1 is preferably between 1 cm and 6 cm.
Distance s 2 is dependent on the pressure of purifying material supplying system 60 and the supplied amount (V) of the gas, i.e., the flow rate of the gas going through that space. From the experimental results, in the case that the supplied amount (V) is 100˜800 L/hr, the results are optimum when distance s 2 is between 2 cm and 8 cm.
Distances s 2 and s 3 are also dependent on the number of fins 71 and 72 . From the experimental results, when the number of fins is two, the sum of distances s 2 and s 3 is preferably distance s 2 plus 5 mm to 30 mm.
For distance h 2 , it can be appreciated that, from theory, the smaller the distance, the better the result. But considering the effect of temperature and so on, the distance h 2 is preferably between 5 mm and 50 mm.
Distance h 3 is related to distance h 2 and the position of guiding element 70 . From the experimental results, distance h 3 is preferably between 5 mm and 30 mm.
For distance h 1 , in the case that the plasma arc heater 50 is used in the experiment, 5 cm is suitable. However, the use of plasma arc heater 50 is potentially dangerous, so a reasonably good result is obtainable if distance h 1 is between 1 cm and 18 cm.
Furthermore, FIG. 9 is a schematic diagram depicting dimple 90 formed by irradiation by the plasma arc heater 50 and/or circulation in silicon melt 100 induced by purifying material supplying system 60 . When plasma arc heater 50 emits plasma and purifying material supply system 60 supplies high-pressure and high-speed jet flow to the center of the surface of silicon melt 100 , a dimple 90 is formed thereon, and as plasma is irradiating the dimple 90 , the high-temperature area on the surface of silicon melt 100 is expanded. In conjunction with the temperature profile across silicon melt 100 in crucible 20 formed by the plasma arc heater 50 , a greater inversion radius of heat circulation in silicon melt 100 is produced. The heat circulation redistributes the impurities within silicon melt 100 more evenly. The jet flow facilitates mixing of silicon melt 100 in crucible 20 , and also expands the contact area between silicon melt 100 and the purifying materials (e.g., gases and chemicals), thereby increasing purification efficiency. In addition, the plasma from plasma arc heater 50 can be applied intermittently to prevent overheating of overall silicon melt 100 and to maintain an appropriate temperature profile across silicon melt 100 in crucible 20 .
FIGS. 11 , 12 , and 13 are schematic diagrams depicting the irradiation of the surface of silicon melt 100 in crucible 20 using various sets of plasma arc heaters 50 .
When a large amount of raw silicon has to be purified, a plurality of plasma arc heaters 50 can be used to generate irradiation of higher energy. However, when a plurality of plasma arc heaters 50 is used to irradiate the center of the surface of silicon melt 100 at the same time, it may overheat and damage the purifying apparatus, for example, overheat and damage the bottom of crucible 20 . In order to overcome such a problem, the present invention arranges a plurality of plasma arc heaters 50 around the center of the surface of silicon melt 100 at equal angular distances. For example, FIG. 11(A) is a schematic diagram depicting three plasma arc heaters 50 surrounding center a of the surface; FIG. 11(B) four plasma arc heaters 50 ; FIG. 11(C) five plasma arc heaters 50 ; and FIG. 11(D) six plasma arc heaters 50 . In the above combinations of plasma arc heaters 50 , the irradiation from the plurality of plasma arc heaters 50 is required to focus somewhere below the surface of silicon melt 100 to avoid overheating of crucible 20 , while ensuring good heat circulation of silicon melt 100 .
Referring to FIG. 12 , plasma arc heaters 50 are arranged at certain angles with respect to the surface of silicon melt 100 . Different angles produce different forms of dimple 90 . The angle should be smaller than or equal to 90° (≦90°. As shown in FIG. 12 , plasma arc heaters are arranged at angles α and β above the surface of silicon melt 100 , which determines the irradiation focus of the plasma. Normally, the deeper the irradiation, the greater the angles α and β. In addition, the temperature profile of silicon melt 100 in crucible 20 will also change in accordance with the change in angles of plasma arc heaters 50 . The dimples 90 that are formed will be different, which implies that varying the irradiation angles changes the evaporation rate of silicon melt 100 . As shown in FIGS. 13(A) and 13(B) , different dimples 90 are formed when plasma arc heaters 50 at different angles irradiate the surface of silicon melt 100 . Further, it should be noted that, by controlling the positions of plasma arc heaters 50 using crucible manipulating device 30 , various positions and temperatures of optimum plasma irradiation can be obtained, and the form of the dimples 90 depends on the irradiation angles α and β of plasma arc heaters 50 .
The preferred embodiments of the present invention are described in detail below with respect to the aforementioned drawings.
The present invention addresses the issue of how to efficiently mix purifying materials (e.g., chemicals and gases) into metallurgical silicon to be purified.
The melting temperature of metallurgical silicon is about 1425° C. There is the possibility that the purifying materials will be nebulized and exhausted due to circulation of radiation heat of the silicon melt before reaching the silicon melt.
In view of this, the following approach is proposed by conventional techniques.
Purifying materials are blown from the bottom of the crucible. This approach may work in theory, but in practice, the following problems occur. A pressure that is sufficient to overcome the viscosity of liquid silicon melt is required. In addition, in order to avoid backflow, blowing has to be done at a level higher than the surface of the silicon melt, which lengthens the blowing tube, therefore requiring an even higher pressure. In the case that the pressure is temporarily decreased, silicon melt backflows into the tube and solidifies at a low-temperature region, which may result in breaking of the tube due to increased mechanical pressure. Thus, the tube has to be maintained at a certain temperature.
This approach thus has the following problems:
a) Addition of impurities cannot be avoided, i.e., product has a low purity; b) Expensive apparatus; c) Safety issue.
Furthermore, although silicon melt can be mixed and stirred by device of mechanical stirring, considering the high-temperature and viscous environment, the material and mechanical strength requirements of the stirring shaft render no easy solution.
Another approach, the so-called weathering approach, is also used for purification.
This method of purification is commonly used in making iron and aluminum, and is proven to be effective.
This method removes impurities and additives (e.g., magnesium oxide and calcium) by vitrification.
The vitrified impurities float on the surface of the purified metal, and after cooling, they can be removed from the surface by mechanical device to obtain a purified product.
This approach has limitations in terms of the purity level of the final product. However, if this approach is simultaneously adopted with the apparatus of the present invention, the purity can be increased.
The present invention is related to the development of a purification apparatus that allows effective mixing of purifying materials into silicon melt.
It should be understood that the metallurgical silicon purifying apparatus proposed by the present invention can be obtained by modifying existing single crystal silicon puller apparatus. The existing apparatus usually includes a vessel, a crucible, a crucible support and a heater. By implementing at least one of the following device in the existing apparatus, purification of metallurgical silicon is performed using one, some or all of the device simultaneously:
an independent injecting device provided above the crucible for providing plasma, gases and chemicals required for purifying in a high-speed jet flow to the surface of a silicon melt, and forming a dimple on the surface of the silicon melt by its supply tubes, and in cooperation with a temperature profile across the silicon melt, facilitating heat circulation and increasing the circulation inversion radius, as well as increasing the contact area between the purifying gases and chemicals and the silicon melt, thereby increasing purification efficiency; a guiding element with fins thereon provided above the silicon melt in the crucible, at an appropriate location with respect to the crucible and the supply tubes for the purifying gases and chemicals, for guiding damped gas flow rising from the surface of the silicon melt back to the surface of the silicon melt, so that the damped gases effectively contact the silicon melt, wherein the distance between the guiding element and the surface of the silicon melt, the distance between the fins and the silicon melt, and the distance between the interior circumference of the crucible and the fins are critical; a manipulating device provided underneath the vessel for vertically and horizontally shifting and rotating the crucible with respect to the heater to adjust the solidus-liquidus interface to obtain one-directional cooling purification without the need for temperature segregation coefficient management of the concentration of remaining impurities in the silicon melt with respect to the solidus-liquidus line, and allowing effective backflow of the damped gases and controlling the form of the dimple created by the jet flow from the injecting device on the surface of the silicon melt by adjusting the distance between the crucible and the guiding element, wherein a set of valves capable of horizontal motion is further provided in the manipulating device in order to reduce reactions of carbon parts with oxygen when the crucible is taken out or inserted into the vessel by opening/closing the valves; and a vacuum pump provided to regulate the pressure or degree of vacuum inside the vessel and to accommodate evaporating conditions for various impurities.
In summary, the present invention proposes an apparatus, obtained by modifying an existing apparatus, for purifying metallurgical silicon for use as raw silicon in manufacturing solar cells to replace the traditional Siemens method.
Depending upon embodiment, one or more of the following aspects are included.
1. An apparatus for purifying metallurgical silicon obtained by modifying an existing single crystal silicon puller apparatus including a vessel, a crucible, a crucible support and a heater, with the addition of one, some, or all of the following devices for the purification of metallurgical silicon:
an independent injecting device provided above the crucible for providing plasma, gases and chemicals required for purifying in a high-speed jet flow to the surface of a silicon melt, and forming a dimple on the surface of the silicon melt by its specially designed supplying tubes; a guiding element with fins thereon provided above the silicon melt in the crucible at an appropriate location and distances (h 1 ) (h 2 ) (h 3 ) (h 4 ) (s 1 ) (s 2 ) (s 3 ) with respect to the crucible and the surface of the silicon melt for guiding damped gas flow rising from the surface of the silicon melt (as a result of heating at the surface of the silicon melt) back to the surface of the silicon melt, so that the damped gases effectively contact the silicon melt; a manipulating device provided underneath the vessel for vertically and horizontally shifting and rotating the crucible with respect to the heater to adjust the solidus-liquidus interface to obtain purification and to further control the relative position of the crucible with respect to the guiding element and the injecting device above to obtain optimum purification efficiency; and a vacuum pump provided to regulate the pressure or degree of vacuum inside the vessel and to accommodate evaporating conditions for various impurities.
2. The apparatus of claim 1, wherein the injecting device includes an independent chemical and gas supply tube for supplying chemicals, gases and soluble gases to the center of the surface of the silicon melt for purification.
3. The apparatus of claim 1, wherein the injecting device includes an independent high pressure gas supply tube for supplying a high-pressure damped gas mixture to the center of the surface of the silicon melt for purification.
4. The apparatus of claim 1, wherein the injecting device includes an independent purifying material supply system including a chemical and gas supplying tube and a high-pressure gas supply tube for supplying chemicals, gases and soluble gases and a high-pressure damped gas mixture, respectively, to the center of the surface of the silicon melt for purification.
5. The apparatus of claim 4, wherein the end of the tubes in the purifying material supply system have a converging cone shape for increasing jet pressure and flow rate.
6. The apparatus of claim 5, wherein the material of the tubes includes quartz coating material thereon.
7. The apparatus of claim 4, wherein the purifying material supply system has a concentric multi-tube design for supplying at least one of chemicals, gases, soluble chemicals, damped gases and water.
8. The apparatus of claim 7, wherein the concentric multiple tubes include an inner tube longer than an outer tube.
9. The apparatus of claim 8, wherein the outlet of the inner tube supplies at least one of a high-pressure damped gas and water, and the outlet of the outer tube supplies argon gas.
10. The apparatus of claim 7, wherein the concentric multiple tubes include an inner tube shorter than an outer tube.
11. The apparatus of claim 10, wherein the outlet of the outer tube supplies hydrogen gas for reacting with oxygen to form water, and the outlet of the inner tube supplies oxygen for reacting with burning hydrogen to form water.
12. The apparatus of claim 1, wherein the injecting device include at least one plasma arc heater for irradiating the surface of the silicon melt and injecting chemicals and gases required for purification.
13. The apparatus of claim 12, wherein plasma is irradiated intermittently and locally on the surface of the silicon melt to create a reproducible temperature gradient in the silicon melt.
14. The apparatus of claim 12, wherein a plurality of plasma arc heaters are arranged around the center of the surface of the silicon melt at equal angular distances, and the plasma arc heaters are tilted at predetermined angles with respect to the plane of the silicon melt, so the irradiation is focused at a point below the silicon melt surface to form dimples of different forms on the surface of the silicon melt.
15. The apparatus of claim 14, wherein the tilting angles of the plasma arc heaters with respect to the plane of the silicon melt are smaller than or equal to 90° (≦90°).
16. The apparatus of claim 1, wherein the manipulating device includes a crucible manipulating device base, a crucible manipulating device shifting shaft, and a crucible manipulating device motor for controlling the vertical movements of the crucible inside the vessel in order to install or remove the crucible and for controlling the vertical movements and rotation of the crucible in order to move the crucible with respect to the heater, so as to adjust the solidus-liquidus interface for one-directional cooling purification, and in order to control the distance between the surface of the silicon melt and the guiding element above, so that damped gases generated from the surface can be effectively directed back to the silicon melt to facilitate the supply of water for purification, and also, by controlling this distance, to control the form of the dimple created on the surface of the silicon melt caused by direct impact of the jet flow from the injecting device.
17. The apparatus of claim 16, wherein the manipulating device further includes a crucible transporting device and a crucible conveyer belt for transporting the crucible at the end of the purification process.
18. The apparatus of claim 1, wherein the manipulating device further includes a set of valves provided beneath the vessel that can be horizontally closed or opened by a set of valve operating arms, so in the case of installing or removing the crucible into or from the vessel, the valves are opened and closed horizontally to reduce the reaction of carbon parts in the vessel with oxygen, which would affect the purification of the silicon melt.
19. The apparatus of claim 1, wherein the guiding element includes a body and at least one fin extending from the lower edge of the body.
20. The apparatus of claim 1, 2, 3, 12 or 19, wherein in the case that the gas flow rate through the guiding element (V) is 100˜800 L/hour, the distance (h 4 ) from the gas supplying tube of the injecting device to the outlet of the plasma arc heater is 10 cm, which is the maximum value; the distance (h 1 ) from the outlet of the plasma arc heater to the surface of the silicon melt is in a range between 1 cm and 18 cm, with 5 cm being preferable; the distance (s 1 ) from the plasma arc heater to the bore of the guiding element, in the case that the chemical and gas supply tube and the high pressure gas supply tube are lowered to the level of the guiding element, is preferably between 1 cm and 6 cm; the distance (s 2 ) from the plasma arc heater to an inner fin of the guiding element, which is dependent on the pressure of the injecting device and the supplied amount (V) of the gas, i.e., the flow rate of the gas going through that space, in the case that the supplied amount (V) is 100˜800 L/hr, is preferably between 2 cm and 8 cm; the distance (s 2 ) and the distance between fins of the guiding element (s 3 ) are also dependent on the number of fins provided, so that when the number of fins is two, the sum of distances s 2 and s 3 is preferably distance (s 2 ) plus 5 mm to 30 mm; the distance (h 2 ) from a fin to the surface of the silicon melt is preferably between 5 mm and 50 mm; and the longest fin (h 3 ) in the guiding element is preferably between 5 mm and 30 mm.
21. The apparatus of claim 1 , wherein a vacuum pump and a gas flow valve are used to control the gas and gas flow rate in the vessel, with the pump regulating the pressure via a decompression tube to avoid any danger caused by the pressure rising due to constant supply of water steam, to accommodate evaporating conditions for various impurities contained in raw silicon, and to prevent superheating of the silicon melt, thereby ensuring a safe metallurgical silicon purification process.
It is also understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims.
EXAMPLE
To prove the principle and operation of the present invention, we performed certain experiments. We performed the poly-Si purification experiments using several generations of modified conventional single crystal Si ingot pullers. Such pullers included a very small and conventional puller (about 20 Kg Si per charge) to a mid-size puller (about 80 Kg Si per charge). We maintained the crucible apparatus and controls, which were modified to operate in a manner consistent with the present pilot silicon purification apparatus configured for purifying metallurgical silicon. Upon introducing metallurgical silicon, processing such silicon, and purifying the silicon according to the present examples. We achieved purification result of 6N˜7N (e.g., 99.9999 to 99.99999 silicon purity), reaching the desired specification suitable for solar cell applications. The present pilot purifier in operation has been modified from a large size conventional puller (about 140 Kg Si per charge). See, for example, FIG. 14 . Of course, there can be other variations, modifications, and alternatives.
It is also understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims. | The present invention provides a method for forming high quality silicon material, e.g., polysilicon. The method includes transferring a raw silicon material in a crucible having an interior region. The crucible is made of a quartz or other suitable material, which is capable of withstanding a temperature of at least 1400 Degrees Celsius. The method includes subjecting the raw silicon material in the crucible to thermal energy to cause the raw silicon material to be melted into a liquid state to form a melted material at a temperature of less than about 1400 Degrees Celsius. Preferably, the melted material has an exposed region bounded by the interior region of the crucible. The method also includes subjecting an exposed inner region of the melted material to an energy source comprising an arc heater configured above the exposed region and spaced by a gap between the exposed region and a muzzle region of the arc heater to cause formation of determined temperature profile within a vicinity of an inner region of the exposed melted material while maintaining outer regions of the melted material at a temperature below a melting point of the quartz material of the crucible. Preferably, the method removes one or more impurities from the melted material to form a higher purity silicon material in the crucible. | 7 |
BACKGROUND
[0001] This disclosure relates to a continuous mining machine, and more particularly, to a continuous mining machine having a cutter drum member with extendable end portions. The present disclosure is directed to a means for extending, retracting and locking the cutter drum extensions in their extended position.
[0002] In a continuous-mining apparatus of the type employed in this invention, a cutting head mechanism is used to dislodge material from a mine vein and is operable to provide a mine passageway or room into which the apparatus advances and mining progresses. The cutting head mechanism is pivotably mounted on a mobile base to swing in a vertical plane between the mine roof and floor and includes a rotary drum cutting head assembly arranged on a horizontal transverse axis and having teeth or bits which tear away and dislodge the mineral. The apparatus also includes a conventional loading head for gathering the loose mineral on the mine floor and moving it rearwardly and inwardly towards the forward receiving portions of the conveying means of the apparatus. The rotary drum cutting assembly has end portions thereof which can be selectively extended or retracted, to respectively, dislodge mineral from the ribs and corners of the mine passageway and reduce the effective length of the cutting head assembly to provide clearance at the sides of the assembly.
[0003] As shown in FIG. 1 , a continuous mining machine generally designated as 10 , may assume various forms but, for illustrative purposes, herein comprises a crawler base 14 carrying a frame 16 on which a forwardly extending mining boom or support member 18 is pivotally mounted at the forward end of the frame 16 to swing up and down between a mine roof and a mine floor. An elongated mining head member 24 extends transversely to the support member 18 and is rotatably secured thereto at the forward end thereof. The mining head member or cutter head 24 is mounted for powered rotation about a longitudinal axis X-X of the head member. Pivotally mounted at the forward end of the frame 16 and extending forwardly there from beneath the support member 18 is a conventional loading head 26 having oscillatory gathering arms 28 for engaging mine mineral and moving such mineral rearwardly and inwardly towards well known conveying means 30 of the mining machine 10 . Conventional hydraulic jacks (not shown) serve to swing the support member 18 in a vertical plane about the pivot axis thereof and to tilt the loading head 26 about the horizontal axis.
[0004] The elongated mining head member 24 is driven from a pair of motors 34 . As shown motors 34 are in spaced axial alignment and extend generally parallel to assembly 24 . A support member 18 at opposite side portions thereof suitably carries motors 34 .
[0005] The drive from motors 34 rotatably drives a cutting head assembly head shaft 36 . Head shaft 36 extends parallel to the longitudinal axis of the head member 24 and is captively and rotatably supported by tubular gear casing extensions 38 that also extend parallel to the longitudinal axis of the head member. The gear drive system for the mining head member may be that shown in either U.S. Pat. No. 3,617,093 or U.S. Pat. No. 3,695,725, or of other conventional construction.
[0006] As hereinafter described, head shaft 36 rotatably drives: an endless circulating belt type continuous hinge cutter chain 48 , hollow cylindrical rotary drum cutting heads 50 and hollow cylindrical rotary drum cutting head extension portions 52 which include cylindrical portion 66 which are partially slideably, received within the ends of respective heads 50 . The portions 52 are selectively hydraulically extendable and retractable there from. An operator can selectively extend or retract the extension portions via a hydraulic control system.
[0007] Examples of conventional mining machine drum cutter extension means are shown in U.S. Pat. No. 4,489,985, and U.S. Pat. No. 3,516,712.
[0008] In U.S. Pat. No. 4,489,985, as can be seen in prior art FIGS. 2 and 3 , the head shaft 36 drives the outer peripheral member 60 of the cutting head 24 via drive ring 72 which engage a plurality of circumferentially spaced keys 74 . The outer peripheral member 60 is supported on casing extension 38 by bearing 76 and other internal bearings (not shown).
[0009] The hollow cylindrical rotary drum extendable end portions 52 have an inner diameter thereof larger than the outer diameter of cutting head 60 and are rotatably driven by the cutting head 60 . As shown in FIGS. 2 and 3 , a plurality of circumferentially spaced keys 82 has the inner ends thereof fixedly secured to the outer peripheral portion of the cutter head 60 . Consequently, the head 60 drives the end portions 52 by means of keys 82 drivingly engaging respective ones of a plurality of cooperating key ways in member 52 . The keys 82 and the key ways 84 are circumferentially spaced about the inner periphery of the cylinder 52 . The above described key and key way driving arrangement additionally allows for the reciprocal axial movement of cutting head end portions 52 with respect to cutting heads 60 by the axially sliding relationship which exists between keys and key ways 82 and 84 , respectively.
[0010] A hydraulic cylinder 90 , in conjunction with its piston rod 92 , accomplishes the extension of the end portions 52 . The rod 92 is fixedly connected to plate 94 that is slidably mounted within the inner diameter of cylinder 66 of end portion 52 . An annular drive ring 96 is fixedly attached to the inner diameter of cylinder 66 for movement therewith. Drive ring 96 has a plurality of holes 99 within its outer annular surface to accommodate a plurality of bolts 98 which have one end threadably engaged with the piston 94 for movement therewith and the other end fixedly attached by threads to latch release member 100 . The holes 99 located on drive ring 96 have a diameter slightly larger than the diameter of bolt 98 to permit the bolts 98 to slide there through. Consequently the piston 94 and the latch release member 100 move as a unit in the direction of longitudinal axis X-X.
[0011] As can be best seen in FIG. 2 , at least one latch member 102 is pivotally mounted on a mounting ring 104 that is fixedly attached to head shaft 36 for rotation therewith.
[0012] U.S. Pat. No. 3,516,712 discloses a mining machine with an extendable head having a spring return mechanism. The means for extending the extensible head is a hydraulic cylinder. More particularly, as shown in FIG. 5 , there is a shaft 87 extending axially through the mining head 13 . The end mining head section 70 has its telescoping cylinder part 71 slidably mounted on the shaft 87 with a key 88 in a keyway 89 . A slide collar 90 is secured to the outer end of the shaft 87 , and a mating inner cylinder 91 is slidably engaged with the slide collar 90 in sealed engagement. A bore 92 extends through the shaft 87 to the inner cylinder 91 . Hydraulic fluid is delivered through the bore 92 into the inner cylinder 91 to move the telescoping cylinder part 7 . 1 and the end mining head section 70 outwardly relatively to the shaft 87 .
[0013] A coil spring 93 is disposed between the outer mining head section 65 and the telescoping cylinder part 71 . A ring 94 is secured to the outer mining head section 65 abutting one end of spring 93 , and a ring 95 is secured to the inner end of the telescoping cylinder part 71 abutting the other end of spring 93 . In the extended position of the end mining head section 70 , as seen in FIG. 5 , the spring 93 is compressed between the rings 94 , 95 , and the end mining head section 70 is held in its extended position by hydraulic fluid trapped within the inner cylinder 91 . The end mining head section 70 is retracted by release of the hydraulic fluid from the inner cylinder 91 , and the force of the spring 93 between rings 94 , 95 withdraws the telescoping cylinder part along the shaft 87 and within the outer mining head section 65 .
SUMMARY
[0014] It is an object of this disclosure to provide a better drum extension portion than that provided in the above cutting heads. In conventional cutting heads, the forces acting to extend and lock the drum extension portions is sometimes inadequate, resulting in machine operators sometimes welding the drum extension portions in their extended position. It is an object of this disclosure to provide a drum extension portion with more extension force and locking force than in conventional cutting heads. More particularly, the disclosed drum extension force has extension and locking forces more than four times stronger than in conventional cutting heads.
[0015] In this disclosure, there is provided an improved continuous mining machine of the type that includes an elongated body portion mounted on devices for propelling the body portion. A support member is pivotally secured to the body portion and extends forward there from. An elongated mining head member is mounted on the forward end of the support member for powered rotation about a longitudinal axis of the head member. The head member has axially extensible and retractable drum extension portions.
[0016] The drum extension portion includes an inner end structure attached to the main cutting head portion, and an outer cylinder attached to the inner end structure. The drum extension portion also includes an inner cylinder attached to the inner end structure and having an outer surface, and the inner cylinder is coaxial with and received within but spaced apart from the outer cylinder. The drum extension portion also includes an extendable cylinder having an inner annular enlarged end, with a portion of the extendable cylinder being received between the inner cylinder and the outer cylinder. A first space is defined between the inner end structure and the enlarged end of the extendable cylinder. The drum extension portion also includes an end cap having a flange that receives coaxially within it the outer end of the inner cylinder, and the extendable cylinder enlarged end is received between the end cap flange and the outer cylinder. A second space is defined between the inner cylinder and the extendable cylinder and between the extendable cylinder enlarged end and the end cap flange, so that when fluid enters the first space and leaves the second space, the extendable cylinder moves to the extended position, and so that when hydraulic fluid enters the second space and leaves the first space, the extendable cylinder moves to the retracted position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is a partial plan view of a mining machine;
[0018] FIG. 2 is an enlarged view showing a prior main gear casing in a portion of a cutter head assembly, with a latch mechanism in its locked position; and
[0019] FIG. 3 is an enlarged view showing the half of the cutter head assembly as is shown in FIG. 2 with the latch mechanism shown in the unlatched position with the extension retracted.
[0020] FIG. 4 is a section view of one end of a prior art cutter head assembly.
[0021] FIG. 5 is a section view of one end of a cutter head assembly according to this disclosure with the drum extension portion in its retracted position.
[0022] FIG. 6 is a section view of one end of a cutter head assembly according to this disclosure with the drum extension portion in its extended position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Illustrated in FIGS. 5 and 6 is a mining machine cutting structure 200 according to this disclosure. Where like elements are found in FIGS. 1 and 2 of the drawings, reference will be made to FIGS. 1 and 2 .
[0024] The mining machine cutting structure 200 includes a support member 18 , and an elongated cutting head assembly 204 mounted at the forward end of the support member for powered rotation about a longitudinal axis. The cutting head assembly 204 comprises a centrally located main cutting head portion 50 , and at least one drum extension portion 208 located at an end of the cutting head assembly 204 axially outward of the main cutting head portion 50 . The drum extension portion 208 is capable of moving in an axial direction along the longitudinal axis from a retracted position to an extended position with respect to the main cutting head portion 50 . More particularly, the drum extension portion 208 includes a toroidal hydraulic cylinder for selectively extending and retracting the drum extension portion 208 .
[0025] The drum extension portion 208 has an axial inner end adjacent the main cutting head portion 50 and an axial outer end, and the drum extension portion 208 includes an inner end structure 212 attached to the main cutting head portion 50 . The drum extension portion 208 also includes an outer cylinder 216 attached to the inner end structure 212 , and an inner cylinder 220 attached to the inner end structure 212 . The inner cylinder 220 also has an outer surface 224 , and the inner cylinder 220 is coaxial with and received within but spaced apart from the outer cylinder 216 . The inner cylinder 220 is also adapted to be connected (not shown), as is cylinder 66 in FIGS. 2 and 3 , to an outer cutter head 60 .
[0026] The drum extension portion 208 also includes an extendable cylinder 228 and an end cap 230 . The extendable cylinder 228 has an inner annular enlarged end 232 , and a portion of the extendable cylinder 228 is received between the inner cylinder 220 and the outer cylinder 216 . The enlarged end 232 has seals and bearings to support sliding movement of the extendable cylinder 228 between the inner and outer cylinders. A first space 218 is defined between the inner end structure 212 and the enlarged end 232 of the extendable cylinder 228 .
[0027] The end cap 230 has an axially extending flange 236 that receives coaxially within it the outer end of the inner cylinder 220 , the extendable cylinder enlarged end 232 being received between the end cap flange 236 and the outer cylinder 216 . The flange 236 has seals and bearings to support sliding movement of the extendable cylinder 228 between the flange 236 and the outer cylinder 216 . A second space 240 is defined between the inner cylinder 220 and the extendable cylinder 228 , and between the extendable cylinder enlarged end 232 and the end cap flange 236 , so that when fluid enters the first space 218 and leaves the second space 240 , the extendable cylinder 228 moves to the extended position, and so that when hydraulic fluid enters the second space 240 and leaves the first space 218 , the extendable cylinder 228 moves to the retracted position.
[0028] The inner cylinder 220 has an extend port 244 through the inner cylinder 220 and communicating with the first space 218 , and a retract port 248 through the inner cylinder 220 communicating with the second space 240 . Conventional porting (not shown) through the elongated cutting head assembly 204 causes fluid under pressure to selectively enter the ports 244 or 248 to extend or retract the drum extension portion 208 .
[0029] Various other features of this disclosure are set forth in the following claims. | A continuous mining machine cutting head structure is set forth. The head member is of the type having axially extensible and retractable end portions. Included within the head member is a toroidal hydraulic cylinder for selectively extending and retracting these end portions. | 4 |
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This non-provisional patent application claims a priority benefit to U.S. Provisional Application No. 61,243,523 entitled “Juggling aid and training apparatus” filed in the United States Patent and Trademark Office on Sep. 17, 2009 by a common Inventor to this instant application, James D. Corridon. Further the above named Provisional Application is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
[0002] Not Applicable
REFERENCE TO APPENDIX
[0003] Not Applicable
FIELD OF THE INVENTION
[0004] This invention relates to devices for capturing projectiles and returning them to a predetermined location.
BRIEF SUMMARY OF THE INVENTION
[0005] The invention is a lightweight portable net configured to assist a juggler in training exercises by capturing dropped balls or other juggling objects onto a sloping surface designed to return the balls to a terminating lip edge for easy retrieval by the juggler. The invention has several embodiments comprising a stand-alone unit, a tabletop unit and a personal accessory unit.
BACKGROUND OF THE INVENTION
[0006] Juggling has been around since the beginning of man, and probably began not long after man found his second stone.
[0007] The earliest known record of juggling is a wall painting from the 15 th century BC Beni Hassan tomb of an unknown prince depicting female dancers and acrobats throwing balls in Egypt rendered about 4000 years ago. These women jugglers were found amongst acrobats and dancers in one of the crypt's wall paintings. Therefore we know juggling has long been a popular activity.
[0008] Learning to juggle takes time and patience. It also takes a great deal of energy to chase down and retrieve errant throws or failed catches. Aids to assist in learning the art, either methods or apparatus are few and far between.
[0009] Earlier aids to assist in learning juggling consist of books, magazine articles, and videotapes. These aids either describe how to juggle or show how juggling is done, but do not directly support the active participation of the student. Since much of learning to juggle is a process of developing the muscle memory of the participant, these “passive” learning aids are necessarily of a limited value.
[0010] The training aid and method described herein provides the user with an enhanced environment of an efficient “hands-on” experience with juggling balls from the beginning of and throughout the learning process, thus developing the requisite muscle memory. The adjustability of the training aid as described below further enhances its value to the user.
[0011] Thus there is a need for a device that will assist a student of the art, no matter how young or old, in learning to juggle in an environment that allows them to focus on the important skills; throwing and catching. Such a device or convenience is heretofore unknown to the inventor. In general this apparatus has the potential for entertaining and improving the quality of life for school children, college students, professional jugglers, and senior citizens in need of mild exercise or occupational therapy. It removes one of the major impediments to learning the art of juggling; the time and energy it takes to chase down and retrieve inaccurately thrown or uncaught juggling pieces.
OBJECTS AND ADVANTAGES
[0012] The primary purpose of this invention is to promote juggling and the teaching thereof, as a form of mental and physical exercise/therapy from the very young to the very old.”
[0013] Accordingly, several objects and advantages of my invention are:
[0014] (a) to provide a participating (rather than passive) training aid for the user which eliminates the time and energy of chasing and or retrieving dropped balls or juggling pieces;
[0015] (b) to provide a user friendly juggling environment, allowing the user to increase or decrease the number of balls being manipulated without multiplying the chase and retrieve factor, thus allows the user to advance his or her juggling skills at his or her own pace;
[0016] (c) to provide a three-dimensional juggling accessory for learning to juggle, whereby the accessory catches, gathers, retrieves, and returns dropped balls to the juggling artist with a minimum of effort on his part, and this apparatus allows the juggler to focus attention more completely on the learning process rather than worrying about erratic tosses;
[0017] (d) to make the learning process of juggling easier and friendlier so as to encourage a broader range of people to participate by lowering the athletic or mobility requirements to participate in the learning process. All the balls are kept in nearby proximity allowing the student an easy retrieval process which further enhances his enjoyment and thus the probability that he will continue with the sport and reap the benefits of the activity, whether for entertainment, exercise or therapeutic value; and
[0018] (e) to provide more practice time spent in active juggling and less time chasing after erratically tossed balls.
[0019] Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a front perspective view of a first embodiment of the invention.
[0021] FIG. 2 is a side perspective view of the invention in FIG. 1 ;
[0022] FIG. 3 is a top view of the invention in FIG. 1 ;
[0023] FIG. 4 is a front three-quarter perspective view of a second embodiment of the invention;
[0024] FIG. 5 It is a side elevation view of the invention in FIG. 4 ;
[0025] FIG. 6A is a front elevation view of a third embodiment of the invention;
[0026] FIG. 6B is a side elevation view of the invention in FIG. 6A ;
[0027] FIG. 7 is a front perspective view of a fourth embodiment of the invention;
[0028] FIG. 8 is a front perspective view of a modification of the invention in FIG. 7 ;
[0029] FIGS. 9A-9E are views of various components of a tabletop embodiment of the invention;
[0030] FIG. 10 are detailed notes that accompany FIGS. 9A to 9E ;
[0031] FIG. 11 is front perspective view of the invention in FIG. 1 ;
[0032] FIG. 12 is a side elevation view of the invention in FIG. 11 showing the Velcro attachment to the front bar;
[0033] FIG. 13 is a side elevation view of the invention as shown in FIG. 12 with the Velcro seam partially opened up;
[0034] FIG. 14 is a side elevation view of the invention as shown in FIG. 11 ; and
[0035] FIG. 15 is a close up view of the webbed netting and rear bar of the invention of FIG. 11 .
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0036] Now referring to FIG. 1 a first embodiment of the juggling trainer 2 is shown. In this embodiment a net 4 is supported by a tubular frame 6 . The frame 6 consists of a pair of adjustable front legs 8 and a pair of adjustable rear legs 10 . The adjustable front legs 8 are further connected by a V-shaped front bar 12 which also serves as the attachment surface for the front edge 14 of the net 4 . The adjustable rear legs 10 are further connected by a straight horizontal rear bar 16 which also serves as the attachment surface for the rear edge 18 of the net 4 . It should be noted that in the optimum configuration the rear bar 16 is set at a height higher than the front bar 12 . This gives the net 4 a slope such that when a dropped juggling ball falls onto the net 4 , it will roll towards the front edge 14 .
[0037] Although many different materials may be used to fabricate the frame 6 , a strong and lightweight material such as aluminum is preferred. Minimizing weight of the device is an important goal for transportation considerations such as shipping costs and ease of personal transportation to and from events by a juggler. Plastic may also be used in some applications as it is usually less expensive than aluminum. The choice of the frame material will be driven by transportation costs and handling objectives.
[0038] For similar reasons the flexible net 4 is preferably constructed from a light weight nylon mesh. Nylon is know for its strength and light weight, although other materials with like qualities may be used.
[0039] In general the juggling artist will stand in the footprints 20 A & 20 B so that he faces the front edge 14 of the net 4 as he begins his training routine. Normally when a juggler is practicing he will often drop balls and they will fall to the floor. He then must chase the balls as they roll across the floor and finally bend over or squat down to pick them up. Especially for beginners the retrieval and chasing of dropped balls is very time and energy consuming. Thus instead of learning how to throw and catch balls, the juggler spends most of his time chasing and retrieving balls. This leads to a very dissatisfying experience and ultimately does very little to encourage and keep new juggling artists in the art.
[0040] Similarly for older folks the requirement of bending over to retrieve dropped balls essentially eliminates juggling as an activity as bending over can be impossible, dangerous, very uncomfortable, or just plain impossible.
[0041] The height of the net 4 in FIG. 1 can easily be adjusted to accommodate a juggler's preference, sitting jugglers, wheel chair jugglers, and or jugglers of different ages and sizes. Both the front legs 8 and their respective rear legs 10 are assembled with telescoping portions and secured by pins 22 as is well known in the art. A series of through holes (not shown) in the upper portions of both the front legs 8 and the rear legs 10 is used to adjust independently the height of the front bar 12 and the rear bar 16 .
[0042] In a preferred embodiment the outer frame member has a single through hole while the inner tubular member has a series of through holes. Thus the inner member is slid relative to the outer member until the desired frame height is achieved and then the pin is inserted to lock the nearest inner hole with the fixed outer hole. It is well known that the hole arrangement just mentioned can be reversed such that the outer member has a series of through holes while the inner member has the singular through hole. The plurality of holes are preferably spaced 1 ″ apart but this can be changed to accommodate other design parameters as well.
[0043] Another method well known in the art are spring loaded buttons which are mounted and protrude from the inner tube member into locking holes in the outer tube member. The outer tube is slide along the inner tube until the spring loaded button locks into the desired hole in the outer tube. Either method may be used depending upon manufacturing and cost considerations.
[0044] Although a tubular frame 6 is disclosed, the frame 6 may be constructed of rectangular or triangular stock. The object of the invention remains however, that regardless of the frame cross-sectional geometry, the legs 8 & 10 must slide adjustably into their respective counterparts, the front bar 12 and rear bar 16 .
[0045] The front legs 8 may also be adjusted in height to accommodate wheelchair bound jugglers. The height is adjusted so that the wheelchair arms (not shown) may slide under the front edge 14 of the net 4 . This is a particularly useful feature for assisted-care facilities and nursing homes where wheelchair patients are fairly common.
[0046] The V-shaped front bar 12 causes two converging slopes 24 A, 24 B in the net 4 such that the convergence meets in the middle of the net 4 and becomes more pronounced as the slopes 24 A, 24 B approach the front edge 14 of the net 4 . This double slope 24 A, 24 B causes any balls which are captured by the net 4 to roll not only towards the front edge 14 of the net 4 , but also towards the middle. In essence in a few short seconds, any dropped balls will immediately be presented to the juggler in front of him and at a height which makes it extremely easy to pick the ball up and begin juggling again. Thus the whole experience of chasing and retrieving dropped balls and the attendant waste of time is eliminated from the juggling experience.
[0047] Furthermore the juggling trainer 2 as shown in FIG. 1 has four rubber anti-skid pads 26 attached to the bottom horizontal tubes 28 to prevent the trainer 2 from sliding unwantedly across the floor. It should be noted that in a further embodiment these pads 26 may be replaced with roller wheels 30 (not shown) so that the trainer 2 may be easily moved about. In the embodiment with roller wheels 30 , the juggler may also wear a small harness 32 (not shown) which attaches the V-shaped front bar 12 semi-rigidly in close proximity to his body so that as he moves about the room, the trainer 2 moves with him. This embodiment would most likely be used by an experienced juggler.
[0048] Referring now to FIG. 2 a side perspective view of the juggling trainer 2 is shown. This is the same embodiment as in FIG. 1 . In this view one can easily see the higher elevation of the rear bar 16 in comparison to the V-shaped front bar 12 . The two converging slopes 24 A, 24 B of the net 4 are also more pronounced in this view. It should be noted that the front edge 14 of the net 4 is attached to the underside of the V-shaped front bar 12 . This is important because the V-shaped front bar 12 also serves as a barrier to stop the rolling balls and keep them on the net 4 . Without this barrier, though balls would continue to roll right off the net 4 and back onto the floor. The net 4 is also designed to have some slack so that it droops slightly right before it reaches the V-shaped front bar 12 . This drooping assists in keeping the rolling balls from jumping over the V-shaped front bar 12 . If the missed juggling balls which are then caught by the net 4 roll off the net 4 by rolling over the front edge 14 , the juggler can easily raise the height of the front edge 14 of the net 4 to prevent this. Thus the slope of the net 4 is set or adjusted by the juggler when he sets the respective front and rear heights of the frame 6 .
[0049] Each edge of the net 4 that attaches to the frame 6 , that is to say, the front edge 14 and the rear edge 18 are quickly and simply attached to their respective frame members, the front bar 12 , and the rear bar 16 , by a pair of parallel Velcro hook and loop strips sewn into the net 4 , spaced apart, along these respective front and rear edges. Each strip is about 0.5″ wide and extends along the entire length of the net 4 being secured. The front edge 14 of the net 4 is simply wrapped around the frame so that a Velcro hook end strip mates onto its companion Velcro loop mating strip. The end strip is on the very edge of the net 4 and the companion mating strip is sewn about 2 inches from the edge so as to leave enough space for the net edge to wrap around the frame. Each attaching edge of the net, when mated, thus creates a sleeve that wraps around its respective frame member, securing and holding the net in place, but also allowing for any necessary sliding motion along the frame member for positioning the net. This anchoring technology is well known in the art.
[0050] Referring now to FIG. 3 a top plan view of the juggling trainer 2 is shown. The position of the juggling artist is shown by the footprints 20 A, 20 B. In this figure, three dropped balls 32 A, 34 A, 36 A have landed on the net 4 having two slopes 24 A, 24 B as previously described. The first ball 32 A will roll down the first slope 24 B and be directed towards the middle of the V-shaped front bar 12 to its final resting location 32 B. The second ball 34 A will roll straight down the middle of the net 4 and be directed towards the middle of the V-shaped front bar to its final resting location 34 B. The third dropped ball 36 A will roll down the second slope 24 A and be directed towards the middle of the V-shaped front bar 12 to its final resting location 36 B. It is obvious that any ball which lands on the net 4 will be directed towards the middle of the V-shaped front bar 12 so that a juggler standing in the footprints 20 A, 20 B will be able to easily and quickly retrieve the dropped balls. The juggler is therefore spending most of his time actually throwing and catching the balls. The trainer 2 therefore enhances his pleasure and experience which will encourage him to continue in the art.
[0051] Referring now to FIG. 4 a second embodiment is shown. This is the tabletop trainer 42 . A net 4 is supported on a table 44 by two front posts 46 and two rear posts 48 . The front posts 46 are designed to be shorter in height than the rear posts 48 so that the net 4 slopes downhill from the rear edge 46 to the front edge 48 . All four edges of the net 4 as a bungee cord sewn along the perimeter of the net 4 . The bungee cord is sized and tensioned to give the net 4 the same sloping characteristics as in the first embodiment. The front posts 46 and the rear posts 48 all have a clamping mechanism (not shown) as their base so as to easily attach to any common tabletop. Once again the juggler stands in the footprints 20 A, 20 B so as to be in close proximity to the front edge 48 of the net 4 . As in the first embodiment, dropped balls will land on the net and roll down towards the juggler. The net 4 is tensioned so as to contain a similar droop at the front edge 48 which creates a barrier to keep the balls from rolling off the net 4 and onto the floor.
[0052] Referring now to FIG. 5 a side elevation view of the tabletop trainer 2 is shown. In this view the rear posts 48 being longer than the front posts 46 raise up the back of the net 4 and create the necessary slope so that a falling ball 50 A lands on the net 4 at location 50 B, and then rolls down the net 4 to location 50 C which is in immediate proximity to the front edge of the net 4 . A juggler standing in the footprints 20 A, 20 B will retrieve the dropped balls in a quick and effortless manner. This embodiment is highly portable as the only components are the posts 46 , 48 and the net 4 .
[0053] Referring now to FIG. 6A a third embodiment of the present invention is shown. In this embodiment the juggling trainer 2 is attached to the juggler by means of a belt 60 which has multiple supporting rods 62 which support the net 4 in front of the juggler and maintain the desired slope so that any dropped balls roll down the net 4 towards the jugglers belt 60 . This embodiment allows the juggler to move about the room with us giving him greater freedom to try more complicated juggling patterns.
[0054] Referring now to FIG. 6B a side view of the embodiment in FIG. 6A is shown. The slope of the net 4 will cause any dropped balls to return to the jugglers waist. This device is made of very light weight materials and easily folds up and fits into a backpack for easy transportation.
[0055] Referring now to FIG. 7 a fourth embodiment of the present invention is shown. A circular shaped net 4 has an outer perimeter 70 and an inner perimeter 72 with adjustable supporting legs 74 so that the outer perimeter 70 as a higher elevation than the inner perimeter 72 . Similar to the other embodiments the net 4 is sloped towards the juggler so that any dropped balls will travel along the slope of the net 4 to close proximity of the juggler. In this embodiment the juggler is free to rotate 360 degrees as he juggles.
[0056] Referring now to FIG. 8 a modification of the embodiment in FIG. 7 is shown. A hingible flap 74 in the net 4 folds open to create a pathway for a juggler to walk into the center of the net 4 . Once the juggler has entered to the center of the net 4 he may close the flap 74 and the Velcro hook strip 76 will mate with the Velcro loop strip 78 to create a firm and secure joint. The juggler is then completely encircled by a 360 degree net 4 . Once again the outer perimeter 70 of the net 4 is at a higher elevation than the inner perimeter 72 so that any dropped balls will roll towards the juggler and stop at the edge of the inner perimeter 72 for easy retrieval.
[0057] Referring now to FIG. 9A a table clamp for use in the tabletop embodiment is shown. A clamp is attached to each corner of the table as shown in FIG. 9B . In FIG. 9C an 18 ″ rod projects from the clamp at approximately a 45 degree angle. The netting as shown in FIG. 9E will attach to the rods with one clamp for each corner of the mesh netting.
[0058] Referring now to FIG. 11 , a front perspective view of the invention is shown. The telescoping features of the front legs and the rear legs can be seen as the front bar is bent at 90° on each end so that the vertical portion slides telescopically into the U-shaped base leg. There is a U-shaped base leg on each side of the invention. The front portion of the U-shaped base leg receives one end of the front bar into each side.
[0059] Referring now to FIG. 12 , a side elevation view of the invention in FIG. 11 is shown. The Velcro seam comprising Velcro hooks 64 and Velcro loops 66 demonstrates how the simple sleeve pocket is formed that wraps around the front V-shaped bar to attach the net.
[0060] Referring now to FIG. 13 , the same view of the invention is shown as in FIG. 12 , however the Velcro joint has been peeled open to reveal the strips of Velcro as attached to the net. As is known in the art, one of the Velcro strips comprises hooks, while the other strip is known as loops or pile. Further the telescoping joint is shown where the front V-bar slides into the upper right leg of the lower U-shaped base bar.
[0061] Referring now to FIG. 14 , a side elevation view of the invention is shown with three juggling balls which have all returned to the front edge of the invention due to gravity and the sloping aspect of the net. Notice the close proximity of the balls to the front perimeter of the apparatus. This makes retrieval by juggler effortless.
[0062] Referring now to FIG. 15 , a close-up view of the upper left-hand corner of the invention is shown. The net is made of a nylon webbing material which has the characteristics of lightweight and flexibility. The net can easily be folded into a very small volume when detached from the frame. The net has a solid perimeter made from a nylon strap of approximately 2 inches in width. The main webbing of the net is captured all around its perimeter by the nylon strap.
[0063] Note also how the rear bar is bent 90° on the left side and because it is of smaller diameter than the U-shaped base bar, it slides telescopically into the U-shaped base bar.
[0064] While the present invention has been illustrated and described with reference to exemplary embodiments thereof, various modifications will be apparent to and might readily be made by those skilled in the art without departing from the scope and spirit of the present invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but, rather, that the claims be broadly construed. | An apparatus for assisting in learning the art of juggling comprises a sloping net which is supported by a structure or worn by the juggler himself, whereby any errantly thrown or dropped balls are caught by the net and returned to close proximity of the juggler so that he can easily pick them up and begin to juggle again. Thus the juggler is relieved of and no longer required to waste time and energy chasing lost balls and more importantly having to bend over or squat down to the floor surface to retrieve them. | 0 |
BACKGROUND OF THE INVENTION
[0001] The invention relates to a metallic insert to be embedded into an opening of a structural member of a material of relatively low strength, in particular of thermoplastic material.
[0002] A metallic insert of this type, in particular a threaded insert, generally is inserted into the respective opening of the structural member while the plastic material surrounding the opening of the structural member is being molten by heat or ultrasonic energy, and thereafter the insert is pressed into the opening by a respective force (heat embedding, ultrasonic welding). Furthermore, it has become known to embed the metallic insert into the material of the structural member by cold deformation or injection molding of the material. In order to secure the insert against extraction and rotational movements, the insert generally has its peripheral surface provided with surface irregularities such as undercuts, grooves, flutes, toothings, etc. For example, U.S. Pat. No. 4,046,181 discloses an insert having a main body comprising a plurality of coaxially superimposed truncated cones which are provided with toothings at their peripheries. These measures allow to decrease the forces required to press the insert into the structural member and to increase the resistance to relative rotational movements. At the same time, however, this will decrease the insert's resistance to extraction. The requirements for small embedding forces and high resistance to extraction and rotational movements are not really compatible to each other.
SUMMARY OF THE INVENTION
[0003] It is an object of the invention to provide a metallic insert to be embedded into an opening of a structural member of relatively low strength, which is of maximal resistance to extraction and relative rotational movements and nevertheless requires only minimal embedding forces.
[0004] The metallic insert of the present invention has a main body comprising a plurality of axially superimposed truncated cones and a recessed portion adjacent a terminal truncated cone. The recessed portion is provided with at least two radial ribs to increase the insert's resistance to relative rotational movements.
[0005] Due to the presence of said radial ribs it is not necessary to provide toothings at the peripheries of the truncated cones. The required resistance to relative rotational movements is obtained by the radial ribs which do not increase the forces required for embedding the insert into the opening of the structural member. Furthermore, the insert of the invention has a relatively high resistance to extraction because the truncated cones of the main body do not require any toothings at their peripheries.
[0006] Rather, it is sufficient to provide the truncated cones with e.g. two rows of axially aligned grooves which enable material flow towards said recessed portion when the insert is pressed into the opening of the associated structural member. Preferably, an annular flange is provided adjacent said recessed portion, with said annular flange being of a diameter equal to or greater than the maximal outer diameter of the radial ribs. This ensures that the material of the structural member which has been molten or otherwise deformed during the embedding operation will be collected and rigidified in the recessed portion.
[0007] The insert of the invention is of relatively high resistance both to extraction and relative rotational movements and nevertheless requires only relatively small embedding forces. Furthermore, it is of relatively simple geometrical shape so that it can be made at minimal cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] For the purpose of facilitating the understanding of the invention, there is illustrated in the accompanying drawings a preferred embodiment thereof, from an inspection of which, when considered in connection with the following description, the invention, its construction and operation, and many of its advantages should be readily understood and appreciated.
[0009] [0009]FIG. 1 is a perspective view of an insert;
[0010] [0010]FIG. 2 is a side elevation of the insert of FIG. 1;
[0011] [0011]FIG. 3 is a side elevation of the insert rotated about 90° with respect to FIG. 2;
[0012] [0012]FIG. 4 is a bottom view of the insert;
[0013] [0013]FIG. 5 shows a detail indicated by Y in FIG. 2;
[0014] [0014]FIG. 6 shows a detail indicated by X in FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] Referring to FIGS. 1 to 4 , the metallic insert shown therein is to be embedded into a bore or other opening of a structural member (not shown) which is made of a material of relatively small strength such as plastic material. Preferably the insert is embedded into a structural member of thermoplastic material by a heat or ultrasonic or inductive embedding operation. As an alternative the insert can be embedded into the structural member by injection molding or pressing in a deforming operation.
[0016] The insert comprises a main body 2 which consists of a plurality of coaxially superimposed truncated cones 4 a , 4 b , 4 c and 4 d . The main body 2 is of generally conical shape in order to facilitate the embedding operation. A further advantage thereof is that the energy which is required to plastify the plastic material during the heat embedding operation will be transferred more quickly from the metallic insert to the structural member. It should be noted, however, that the main body 2 could also be of a generally cylindrical shape depending on the requirements of a special application.
[0017] The truncated cones 4 a to 4 d preferably are of the same height which is selected depending on the material and dimensions of the structural member and will be given by a certain percentage of the total length of the insert. In order to provide for the general conical shape of the main body the diameters of the truncated cones 4 a to 4 d are reduced stepwise in the so-called extraction direction which is indicated by arrow x in FIGS. 1 and 2. More precisely, the circumferential lines 13 and 15 of the large and small base surfaces 12 and 14 of the truncated cones 4 a to 4 d each lie in a virtual conical surface having a cone angle of preferably about 4°. It should be noted, however, that the cone angle could be greater and smaller depending on the specific application.
[0018] The cone angle of the truncated cones 4 a to 4 d preferably is between 60° and 90°; i.e. the half cone angle α (see FIG. 6) is between 30 and 45°. The greater the cone angle, the greater are the undercuts between the various truncated cones thereby to increase both the resistance to embedding and the resistance to extraction. Therefore, an acceptable compromise can be found depending on the specific application and in particular on the strength of the material of the structural member. Basically, the smaller the strength of the material of the structural member will be, the larger should be the angle α.
[0019] Adjacent to the large base surface 12 of the terminal truncated cone 4 d there is a recessed portion 7 comprising an annular groove which is limited on its opposite side by an annular flange 6 . In the embodiment as shown both the peripheral surface of the recessed portion 7 and the peripheral surface of the annular flange 6 are of cylindrical shape. It should be noted, however, that other geometrical shapes could be provided.
[0020] The recessed portion 7 is provided with a pair of radial ribs 16 offset with respect to each other by 180°. It would be possible to provide more than two radial ribs, for example three or four ribs.
[0021] As shown in particular in FIGS. 1 and 3, the ribs 8 are confined by lateral surfaces 16 which are inclined with respect to an axial plane and which include an angle of about 30 to 60°. The radially outer sides 18 of the ribs 8 are slightly inclined with respect to the axis of the insert, in conformity with the general conical shape of the main body 2 . Accordingly, the radially outer sides 18 of the two ribs 8 also include an angle of about 4°.
[0022] As indicated in FIGS. 1 to 3 , the ribs 8 extend from the recessed portion 7 axially into the area of the truncated cones 4 d and 4 c and could be prolonged so as to extend for example also into the area of the truncated cone 4 b . The arrangement is such that the radially outer sides 18 of the ribs 8 are disposed in the virtual conical enclosing surface which includes also the peripheral lines 13 of the large base surfaces 12 of the truncated cones 8 . The maximal diameter of the radially outer sides 18 of the ribs 8 (adjacent the annular flange 6 ) is equal to or smaller than the outer diameter of the annular flange 6 .
[0023] The purpose of the recessed portion 7 is to receive and take up material of the structural member which is deformed and displaced during the embedding operation. The recessed portion 7 , accordingly, serves as a “dam” for material flow and provides for a substantial undercut thereby to increase the extraction resistance (resistance to axial loading). The annular flange 6 prevents exit of material from the recessed portion 7 . Depending on the specific application the annular flange could be dispensed with.
[0024] The radial ribs 8 provide for high resistance to relative rotational movements. Due to their specific geometrical shape they do not affect the finding (threading) and embedding operation.
[0025] The truncated cones 4 a to 4 d are provided with axially extending peripheral grooves. As shown in FIGS. 1 to 4 the grooves 10 are arranged in a pair of rows of axially aligned grooves which are circumferentially offset with respect to the ribs 8 for 90°. Instead of two rows there could be provided more than two rows, for example three or four rows.
[0026] The grooves 10 are provided to allow for material flow during the embedding operation in the extraction direction x to the next adjacent truncated cone and finally into the recessed portion 7 . If the opening of the structural member is formed as a blind bore, they furthermore allow for “venting” of the blind bore so that there will be no “air cushion” below the insert. The material remaining within grooves 10 , furthermore, assists in increasing the resistance to relative rotational movements.
[0027] The insert shown in the drawing is a threaded insert provided with a threaded bore 20 . It should be noted, however, that a smooth bore could be provided instead of a threaded bore 20 depending on the specific application. Furthermore, the insert could perform the function of a bolt or any other suitable function.
[0028] As already mentioned, the metallic insert is preferably embedded into the opening of a thermoplastic structural member by a heat embedding operation. The insert and the opening of the structural member are dimensioned such that the insert can be inserted into the opening of the structural member for about half of its length without any external force. The general conical shape of the main body 2 facilitates initial positioning of the insert within the opening of the structural member. The insert will be pressed into the molten plastic material of the wall of the opening of the structural member by a predetermined embedding force in a direction opposite to the extraction direction x. The molten material will flow through the axial grooves 10 into the “undercut areas” of the truncated cones 4 a to 4 d where the molten material spreads and forms some kind of a “dam”. A substantial amount of the molten material will eventually flow to the last and most important “dam” which is formed by the recessed portion 7 . The molten material will fill the recessed portion 7 while the annular flange 6 prevents the material from flowing out of the recessed portion 7 . The material which has flown into the undercut areas of the truncated cones 4 a to 4 d and the recessed portion 7 will eventually rigidify. The undercut areas of the truncated cones 4 a to 4 d and in particular the recessed portion 7 will provide for high resistance to extraction in the direction x while the axial grooves 10 and in particular the radial ribs 8 provide for high resistance to relative rotational movements. | A metallic insert to be embedded into an opening of a structural member of a material of relatively low strength. The metallic insert has a main body comprising a plurality of coaxially superimposed truncated cones and a recessed portion adjacent to the truncated cones. The recessed portion is provided with at least two radially extending ribs to increase the insert's resistance to relative rotational movements. As a result thereof the metallic insert which requires only relatively small forces to be embedded into the structural member is of high resistance both to extraction and rotational movements of said metallic insert with respect to the structural member. | 5 |
CLAIM OF PRIORITY
This is a continuation in part application and claims priority to U.S. Utility application Ser. No. 11/561,191 titled “POLYMER OBJECT OPTICAL FABRICATION PROCESS” filed on Nov. 17, 2006 now U.S. Pat. No. 7,778,728.
FIELD OF TECHNOLOGY
This invention relates, generally, to microstereolithography. More particularly, it relates to a non-degenerate two-photon approach to projection microstereolithography.
BACKGROUND
Microstereolithography enables the manufacturing of small and complex three-dimensional components from plastic materials. One-photon polymerization is a process that causes a photo-initiator monomer concentration to induce a photochemical reaction, which in turn causes the concentration to cross-link and solidify.
The process is the basis for most commercially available stereolithography systems. Two-photon polymerization is a technique for the fabrication of three dimensional micron and sub-micron structures. A beam of ultra fast infrared laser is focused into a container holding a photo-sensitive material to initiate the polymerization process by non-linear absorption within the focal volume. By focusing the laser in three dimensions and moving the laser through the resin, a three dimensional structure can be fabricated. Two-photon microstereolithography enables three dimensional processing as well as high complexity micro-fabrication.
Researchers have demonstrated experimental two-photon micro/nano stereolithography but have not incorporated projection technology into the two-photon fabrication process and have not combined non-degenerate two-photon photopolymerization based on intersecting femtosecond pulsed projected images with picosecond pulsed laser light sheet at the focal plane. Existing two-photon stereolithography techniques enable unlimited complexity in the part geometries that can be fabricated by polymerizing a single focal volume voxel inside the bulk volume of photopolymer via the two-photon absorption process. However, these systems are limited in the volume that can be fabricated in a timely manner due to the point-by-point fabrication approach.
These systems also require ultra-precision control of translation or minor steering systems to generate parts of adequate resolution at the micro scale. The trend of everincreasing two-photon absorbing cross-sections of photoinitiators explicitly tailored for two-photon processes in recent years suggests that the speed of the scanning minor systems will also present some limitations in two-photon stereolithography now and in the future.
One-photon based microstereolithography techniques fabricate in a surface layer-by-layer approach that ultimately limits the process to rapid prototyping and some small production runs of micropolymer structures. The surface layer-by-layer approach also limits the geometries of objects that can be fabricated due to surface tension or release layer issues, and requires an extensive network of support structure to be digitally inserted into three-dimensional models via support structure insertion algorithms. All of these factors limit the fabrication process and slows the overall throughput of micropolymer structures.
There also exists a gap between prototyping of complex micro geometries using microstereolithography and mass production of complex geometries. The ideal microstereolithography device would allow any complexity in geometry, need no support structure, and enable rapid prototyping, mass-production, and mass customization from a single machine. Two-photon absorption can occur in two forms: degenerate and non-degenerate. The process is known as degenerate if the photons absorbed are of the same wavelength. The process is known as non-degenerate when the photons absorbed are of two-different wavelengths. Nearly all of the research conducted on two-photon polymerization has been limited to degenerate schemes using a single focused laser beam.
Non-degenerate two-photon polymerization, using two lasers of two different wavelengths, increases set-up costs, requires optical hardware having a more complex configuration and dual laser pulse synchronization. However, a non degenerate configuration offers distinct advantages that have an impact on the overall throughput and versatility of the fabrication system. Non-degenerate systems offer more control over the geometry of the reaction volume due to the fact that the reaction volume is confined only to the overlapping beams of the appropriate wavelengths.
The rate of degenerate two-photon absorption, in a dual intersecting beam degenerate two-photon configuration, increases where the two beams intersect but photo-absorption also occurs in the light path prior to the desired reaction volume if the beams enter a sample already tightly collimated, or at a low numerical aperture. This configuration causes some two-photon absorption (TPA) in the beam delivery paths with an increase in absorption occurring at the intersection of the two beams, thus limiting the overall irradiance that is deliverable to the desired fabrication volume. This situation also limits the achievable speed of photopolymerization and feature size resolution.
For two-photon polymerization photon absorption in the beam's delivery path is an undesired effect and is solved by implementing a focusing scheme with a high numerical aperture. The increase in the probability for absorption to occur as the beam approaches the focal point reduces the possible degenerate configurations to designs that have a high numerical aperture objective lens. Thus there is a need for a two-photon projection microstereolithography method that incorporates a non-degenerate two-photon approach to projection micro stereolithography but which is not subject to the limitations of the known methods. However, in view of the art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in this art how the identified needs could be met.
SUMMARY
The long-standing but heretofore unfulfilled need for improvements in microstereolithography is now met by a new, useful and nonobvious invention. The novel two-photon projection microstereolithography process_incorporates an innovative non-degenerate two-photon approach to projection_microstereolithography.
More particularly, non-degenerate two-photon_absorption enables single-step, all digital, mass fabrication of micro-polymer or_polymer-derived-ceramic structures of virtually any three-dimensional geometry_directly from computer model design files. This single-step fabrication process is for convenience referred to as the Polymer Object Optical Fabrication (POOF)_process, which acronym suggests the extremely fast microfabrication of three-dimensional_micro polymer structures of unlimited complexity in part geometry_including virtually any aspect ratio desired.
The POOF process further evolves the known stereolithography process by taking a projection-based, non-degenerate two photon induced photopolymerization (TPIP) approach to stereolithography. Incorporating a spatial light modulator such as Texas Instrument's Digital Light Processor (DLP™) projection technology into the two-photon fabrication process introduces a highly parallel approach to microstereolithography that substantially reduces or eliminates the need for support structure, provides unlimited part geometrical complexity (within a finite range of micro resolution smallest feature sizes) in resulting parts, and provides the optical and mechanical configuration that enables rapid prototyping, high-volume mass-production, and mass-customization of micro polymer and micro-polymerderived-ceramic structures from a single machine in a single step.
This process is used in conjunction with photoinitiators with a high two-photon absorption cross-section combined with various acrylates, vinyl ethers, epoxies, bio-degradable hydrogels, elastomers, or polymer-derived-ceramics to make complex microstructures for Micro Electro Mechanical Systems (MEMS) and integrated complex three-dimensional optical circuitry for MicroOptoElectroMechanical (MOEMS) devices for a wide range of industries. POOF technology will be an integral tool in the development of polymer and ceramic-based MEMS and MOEMS technologies with a special emphasis on packaging fabrication for current and emerging MEMS and MOEMS' devices.
The fabrication capability of the POOF process enables the fabrication versatility and throughput of micro geometries currently not feasible with existing fabrication techniques.
BRIEF DESCRIPTION OF THE VIEWS OF DRAWINGS
FIG. 1 is a diagrammatic side elevational view of a first embodiment;
FIG. 2 is a diagrammatic end view of the FIG. 1 structure;
FIG. 3 is a diagrammatic top plan view of the FIG. 1 structure;
FIG. 4 is a diagrammatic end view of a second embodiment;
FIG. 5 is a diagrammatic side elevational view of the second embodiment;
FIG. 6 is a diagrammatic side elevational view of a third embodiment; and
FIG. 7 is a diagrammatic top plan view of said third embodiment.
DETAILED DESCRIPTION
This invention includes a method for the patterned solidification, desolidification, or modification of the index of refraction of a photo reactive material by non-degenerate two-photon absorption thereby providing rapid fabrication of three-dimensional micro-structures directly from computer models.
The steps of the novel method include: Placing a medium capable of selective solidification, desolidification, or refractive index modification via non-degenerate two-photon absorption into a container having at least one optically transparent window so that the medium within the container is accessible by laser light. In the alternative, the entire container may be made of an optically transparent material; Providing an array of controllable pixel elements; Selecting two synchronized pulsed laser sources having respective wavelengths to induce non-degenerate two-photon polymerization; Providing an optical projection system for projecting patterned images of femtosecond pulsed laser light; Directing femtosecond laser pulses onto the array of pixel elements, so that a desired patterned portion of source light travels through the window of the container and into the photoreactive material and focuses inside the photoreactive material;
Providing an optical system for producing the sheet of light of picosecond pulsed laser light so that sheet has an optimal thinness and flatness, Aiming the femtosecond patterned light and the picosecond sheet of light so that they intersect one another orthogonally with the two focal planes overlapping. More particularly, directing picosecond pulses in a thin, flat sheet so that said picosecond pulses intersect with the femtosecond pulses, such that the thin, flat sheet of picosecond pulses intersects the source light perpendicular to the projected source from the array of pixel elements so that select regions of the photoreactive material are cured at the intersection;
Positioning the container and the photoreactive material therewithin relative to the intersecting focal planes at an angle less than the critical angle of the container material and photoreactive material; Monitoring the real-time velocity of the container through the light intersection region by employing a velocity sensor; Providing a computer control system that sends electronic data for each image pattern to be projected from the controllable pixel element where the refresh rate of the controllable pixel array is throttled according to the velocity data obtained from the velocity sensor. In the alternative, the feedback could alter the conveyor speed, control the laser repetition rate, the light path length, or the controllable pixel array. A finely tuned system may not require feedback;
Providing a computer-executable program for extracting a series of slices of a three-dimensional computer model data into a series two-dimensional image files that are compatible with the controllable pixel elements; Sequentially sending the sequence of two-dimensional images extracted from the three-dimensional computer model file to the controllable pixel array, thereby enabling projection of the slices of the computer model file into the medium as the medium volume translates through the intersecting focal planes at a velocity determined by the photo reactive cure time of the photoreactive material and the real-time velocity feedback data; and Synchronizing overlapping pulses operating at two different wavelengths that are of preselected energies to meet the combined energy requirements necessary to achieve non-degenerate two-photon absorption in the beam intersection volume within the photoreactive material.
The array of controllable pixel elements may include a spatial light modulator and the spatial light modulator may include a plurality of mirrored surfaces each independently pivotable from a first to a second position or state allowing directional control of the area of light reflecting from each mirror. The spatial light modulator is controlled by digital electronics that modify each mirror state by loading a binary array of data. Each bit of data in the binary image array determines the directional pivot of the mirror thus providing spatially patterned projection of laser pulses. The binary array of mirror state data is provided by two-dimensional slice plane image data that is programmatically extracted from a three-dimensional computer model.
The two-dimensional slice plane data extracted from the computer model is in some cases an exact two-dimensional cross-section replica of the desired fabrication geometry and in other cases the extracted slice plane data is processed in such a way as to use the spatial light modulator as a digital programmable holographic grating capable of projecting a holographic image into the medium. The illuminating pulsed laser light of the spatial light modulator is a femtosecond pulsed laser source.
An optical system couples with the spatial light modulator to form a laser illuminated projector that has an aspheric beam shaping condenser lens placed prior to and directed onto the spatial light modulator, a micromirror array spatial light modulator, and a reducing imager lens placed post spatial light modulator and focused to intersect sheet of light. This invention is not limited to a micromirror array spatial light modulator. There are many types of spatial light modulators and all of them are within the scope of this invention.
The aspheric condenser lens redistributes the Gaussian energy distribution of the femtosecond laser light to form a more even energy distribution across the spatial light modulator and thus across the projected focal plane, and the projected image is directed into a region that will allow intersection with the picosecond light sheet and allow the medium and windowed container/cuvette to pass through the intersection region.
Alternatively, the optical imager lens can be used to expand or reduce the total area of the projected image thus decreasing or increasing the build resolution respectively. The sheet of light optical system is capable of creating a thin sheet of pulsed radiance energy from the picosecond source using an aspheric beam shaping cylindrical lens set placed between the picosecond laser source and the beam intersection volume or “fabrication plane.” The aspheric beam-shaping cylindrical lens set redistributes the picosecond laser light Gaussian energy distribution to form a more even energy distribution across the thin light sheet.
The thin sheet of pulsed energy is directed into the vat perpendicular to the focal plane of the femtosecond projected image. Alternatively, the sheet of light optical system can be designed from a diffractive optical element that forms a sheet of light that intersects the focal volume of the projected source. The photoreactive material includes a highly efficient two-photon photoreactive initiator material combined with compatible fast reacting monomers such as acrylates, vinyl ethers, epoxies, biodegradable hydrogels, elastomers, or polymer-derived-ceramics.
The medium may be a liquid resin that is solidified upon exposure to the intersecting beams thus allowing microstructure fabrication. It may also be a solid that is desolidified upon exposure to the intersecting beams thus allow microstructure fabrication. It may also be a material with the capability of altering the index of refraction thus enabling the fabrication of waveguides.
The novel POOF process incorporates a spatial light modulator such as Texas Instrument's digital light processor @LP™) Projection technology into a two-photon fabrication process. It requires a non-degenerate approach to the TPIP process due to the geometry of the projected light entering the bulk volume of the polymer. The POOF process further requires that the projection system be illuminated by a high peak-power, femtosecond, pulsed, laser source operating at a specific wavelength λ 1 which projects a series two dimensional slices of a three dimensional computer model.
The pulsed image is projected into the bulk fabrication volume of photopolymer material through a reducing imager lens of approximately 1.1:1 or greater reduction A high peak-power, nanosecond, pulsed, very thin, flat sheet of laser light operating at a specific wavelength λ 1 , orthogonally intersects the pulsed image at the focal plane of the projection imager lens. At this junction of the femtosecond pulsed image and the thin sheet of picosecond pulsed light the two different wavelengths of light, λ 1 and. λ 2 , will induce non-degenerate TPA thus initiating the free-radical or cationic TPIP process of an entire digitally patterned two-dimensional slice of a computer model in each synchronized dual pulse intersection.
This intersection of femtosecond projected pulsed images intersecting with picosecond pulsed sheet of light is a significant feature of the invention. Non-degenerate two-photon absorption increases the overall complexity of the machine design by requiring two synchronized pulsed lasers. However, another advantage in implementing this configuration exists in the versatility to alter the beam intersection geometry. This allows alteration of the fabricated voxel geometry. Non-degenerate two-photon scheme also enables utilization of lower numerical apertures in a two-photon polymerization process.
This versatility is inherent in the non-degenerate two-photon absorption process because two-photon absorption will only occur in the volume of the pulses intersection where the combined irradiance of each beam plays a contribution to meeting the quadratic irradiance dependence required for TPIP. To ensure an optimized microstereolithography process capable of high volume mass production, the projected image is directed into a vat or cuvette at an angle less than the critical angle of the a transparent vat/cuvette wall and the photopolymer material. This critically important aspect of the POOF configuration meets five crucial conditions during the fabrication of the desired object: A) a static focal plane, B) substantially static optical components in the optical path (excluding minute vat vibration), C) constant velocity translation in a single axis, D) substantially turbulence free photopolymer build volume, and E) an array of up to 4.1 million fabricated voxels digitally projected via a high performance spatial light modulator such as the extremely high performance Texas Instrument's Digital Micromirror Device (DMD).
From an optical, mechanical, and software design perspective, meeting these five important design constraints produces a microstereolithography process that is optimized for high-speed, high-volume microfabrication. Meeting these design constraints also identifies the overall novelty of the POOF technology in an all digital, high-speed, non-degenerate two photon, projection, microstereolithography device for high-volume 3D microfabrication of any geometry.
The basic POOF system includes an enclosed transparent vat containing a two-photon photoinitiator monomer concentration that is meets the criteria of one-photon optical transparency of each of the POOF process's dual synchronized lasers.
The vat is mounted to a low vibration translation system that translates the vat at a constant velocity through the fabrication plane where the pulsed image and sheet of light intersect. The DLP™ Projection system projects a series of high peak power femtosecond pulsed cross-sectional CAD model slice image at a refresh rate defined by the velocity of the translation system and the polymerization rate of the photoreactive material. A picosecond pulsed thin sheet of light is synchronized to intersect the projected pulsed image in the focal plane. Because of numerical apertures of the light entering the photopolymer volume, the wavelength of light, and the irradiance of the pulsed laser light neither single beam alone can induce immediate TPIP. A liquid volume goes in and “POOF,” the three-dimensional part is produced. The thickness of each fabrication slice is determined by the non-degenerate TPIP dynamics of the spatial thickness of the sheet of light interacting with the temporal length of the femtosecond projected pixel in the physical intersection geometry and also by any diffusion of the light as photopolymerization occurs and the termination coefficient of the polymer chain during the reaction.
Further empirical exploration of the intersection beam geometries, with each of the best material candidates, is required to determine the optimal balance of intersecting femtosecond pulse energy dose and picosecond pulse energy dose range that will induce non-degenerate TPIP without causing thermal damage during the fabrication process while maintaining the highest possible throughput of the system.
The POOF process laser systems and optical systems are chosen by meeting the criteria that TPIP occurs only in the intersection volume of the laser beams. Exposing the photopolymer material to either the projected femtosecond pulsed image of wavelength. λ 1 or the picosecond pulsed sheet of light of wavelength λ 2 , alone will not induce immediate TPIP. Only where the beam operating at λ 1 intersects with a second beam operating at λ 2 , where λ 1 and. λ 2 , are of the appropriate combined energies, will the energies sum to induce immediate TPIP.
The picosecond pulse sheet thickness and collimation is constrained to an irradiance limitation below the irradiance induced damage threshold of the photopolymer materials. The optimal theoretical light delivery system working in conjunction with the optimal chemical and hardware configuration facilitates a process capable of high volume production of polymer-based micro-structures with the unprecedented combination of three-dimensional complexity, feature size resolution, and volume throughput. Several conceptual TPIP projection POOF design configurations for mass production are depicted in the drawings that include designs for rapid prototyping or rapid manufacturing of polymer or polymer-derived-ceramic microstructures and a design for high resolution rapid prototyping of micro-feature build resolution of macrostructures.
To fully optimize the overall throughput of this system an optional hardware addition to the overall system is realized by incorporating a magnet that creates a thin, sheet-like, magnetic field across the pulsed light intersection region also called the fabrication region. It is known that photopolymers located in a moderate magnetic field can have an increase in the overall photoefficiency of the photopolymerization process. However, no prior art in the field of stereolithography or TPIP configurations has incorporated a thin magnetic field into the focal region of the incoming light. Increasing the overall photoefficiency of the process results in either lower pulse power requirements to achieve TPIP or an increase in the overall fabrication throughput of the process.
FIGS. 1-3 depict a typical set-up, which is denoted as a whole by the reference numeral 10 . Conveyor system 12 carries container 14 through the fabrication region. As mentioned above, at least part of container 14 is optically transparent. The depicted conveyor system includes a sprocketed belt 16 that makes a continuous path of travel around sprocket pulleys 18 a , 18 b that are longitudinally spaced apart from one another and which are respectively supported by vibration isolation base members 19 a , 19 b having support legs 20 a , 20 b . Optically flat glass tracks 22 provide a guided path for container 14 through the fabrication region is itself supported by base members 21 a , 21 b and support legs 23 a , 23 b.
Of course, the art of machine design includes numerous equivalent structures for carrying a container along a predetermined path of travel and all of such equivalent structures are within the scope of this invention. The femtosecond pulsed laser is denoted 24 and the picosecond pulsed laser is denoted 26 . The spatial light modulation (SLM) projection system associated with femtosecond pulsed laser 24 is denoted 28 and the femtosecond pulsed laser 24 illuminated projection optics is denoted 30 .
The femtosecond pulsed laser images projected by SLM projection system 28 are denoted 32 . These images are also referred to as the image source light. The flat sheet of picosecond pulsed laser light is denoted 34 is illuminated by the picosecond pulsed laser denoted 26 and formed by the sheet of light optics denoted 35 .
The intersection where the synchronized laser pulses meet, i.e., where images 32 meet flat sheet 34 , is denoted 36 . Intersection 36 is the fabrication region. Thin magnet 38 is positioned in an inclined plane and intersects fabrication region 36 . The structure diagrammatically depicted in FIGS. 4 and 5 differs from the structure of FIGS. 1-3 in that no magnet 38 is provided in this embodiment.
In all other respects, the structure is the same as indicated by the reference numerals, which are common to FIGS. 1-5 . A third embodiment is depicted in FIGS. 6 and 7 . Most of the functional parts are the same as in the first two embodiments as indicated by the common reference numerals. However, instead of a relatively small container 14 that contains the photoreactive material, a large vat 40 contains said material.
Vertical lifting platform 42 is positioned inside said large vat and suitable means are provided for elevating said platform 42 in increments that correspond to the vertical height of the fabrication region 36 as the inventive method is performed. Vat 42 is supported by a dual axis translation system that includes rigid arms 44 , 46 disposed at a right angle relative to one another at the base of vat 42 , externally of said vat. Translation of vat 42 along an x-axis is controlled by arm 44 , along a y-axis by arm 46 , and along a z-axis by vertical lifting platform 20 42 . The z-axis is perpendicular to the plane of the paper in FIG. 7 . In this way the photoreactive material is moved through fabrication region 36 as vat 40 is translated along said axes under the control of a computer.
It will be seen that the advantages set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between. Now that the invention has been described. | High-volume mass-production and customization of complex three-dimensional polymer and polymer-derived-ceramic microstructures are manufactured in a single step directly from three dimensional computer models. A projection based non-degenerate two-photon induced photopolymerization method overcomes the drawbacks of conventional one and two-photon fabrication methods. The structure includes dual, synchronized, high-peak power, pulsed femtosecond and picosecond lasers combined with spatial light modulation. Applications include high-resolution rapid prototyping and rapid manufacturing with an emphasis on fabrication of various Micro-Electro-Mechanical Systems (MEMS) devices, especially in the area of MEMS packaging. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to systems and methods for the manufacturing of microscale or nanoscale concentrically-layered fibers by electrospinning
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] The present invention claims priority to U.S. Provisional Application No. 61/437,886 entitled “Electrospinning Process for Fiber Manufacture,” filed Jan. 31, 2011; and to U.S. application Ser. No. 13/362,467 entitled “Electrospinning Process for Manufacture of Multi-Layered Structures,” filed Jan. 31, 2012.
BACKGROUND
[0003] Macro-scale structures formed from concentrically-layered nanoscale or microscale fibers (“core-sheath fibers”) are useful in a wide range of applications including drug delivery, tissue engineering, nanoscale sensors, self-healing coatings, and filters. On a commercial scale, the most commonly used techniques for manufacturing core-sheath fibers are extrusion, fiber spinning, melt blowing, and thermal drawing. None of these methods, however, are ideally suited to producing drug-loaded core-sheath fibers, as they all utilize high temperatures which may be incompatible with thermally labile materials such as drugs or polypeptides. Additionally, fiber spinning, extrusion and melt-blowing are most useful in the production of fibers with diameters greater than ten microns.
[0004] Core-sheath fibers can be produced by electrospinning in which an electrostatic force is applied to a polymer solution to form very fine fibers. Conventional electrospinning methods utilize a charged needle to supply a polymer solution, which is then ejected in a continuous stream toward a grounded collector. After removal of solvents by evaporation, a single long polymer fiber is produced. Core-sheath fibers have been produced using emulsion-based electrospinning methods, which exploit surface energy to produce core-sheath fibers, but which are limited by the relatively small number of polymer mixtures that will emulsify, stratify, and electrospin. Core-sheath fibers have also been produced using coaxial electrospinning, in which concentric needles are used to eject different polymer solutions: the innermost needle ejects a solution of the core polymer, while the outer needle ejects a solution of the sheath polymer. This method is particularly useful for fabrication of core-sheath fibers for drug delivery in which the drug-containing layer is confined to the center of the fiber and is surrounded by a drug-free layer. However, both emulsion and coaxial electrospinning methods can have relatively low throughput, and are not ideally suited to large-scale production of core-sheath fibers. To increase throughput, coaxial nozzle arrays have been utilized, but such arrays pose their own challenges, as separate nozzles may require separate pumps, the multiple nozzles may clog, and interactions between nozzles may lead to heterogeneity among the fibers collected. Another means of increasing throughput, which utilizes a spinning drum immersed in a bath of polymer solution, has been developed by the University of Liberec and commercialized by Elmarco, S.R.O. under the mark Nanospider®. The Nanospider® improves throughput relative to other electrospinning methods, but it is not currently possible to manufacture core-sheath fibers using the Nanospider®. There is, accordingly, a need for a mechanically simple, high-throughput means of manufacturing core-sheath fibers.
SUMMARY OF THE INVENTION
[0005] The present invention addresses the need described above by providing a system and method for high-throughput production of core-sheath fibers.
[0006] In one aspect, the present invention relates to a device for high-throughput production of core-sheath fibers by electrospinning The device comprises a hollow tube having a lengthwise slit therethrough, which can be filled with a solution of the core polymer, and optionally includes a bath in which the hollow tube is immersed, which can be filled with a solution of the sheath polymer. The tube also optionally includes structural features such as channels or regions of texture or smoothness through which the sheath polymer solution can run. In an alternate embodiment, the device comprises three adjacent troughs arranged so that two external troughs sandwich a central trough. The central trough is filled with a solution of the core polymer, while the external troughs are filled with solutions of the sheath polymer.
[0007] In another aspect, the present invention relates to a device for collection of electrospun fibers in yarn form. The device comprises a grounded collector for electrospun yarns, the collector being configured to rotate so that fibers are twisted into yarns as they are collected from an electrospinning apparatus.
[0008] In yet another aspect, the present invention relates to methods of making core-sheath fibers and electrospun yarns using the devices of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] In the drawings, like reference characters generally refer to the same parts throughout the different views. Drawings are not necessarily to scale, as emphasis is placed on illustration of the principles of the invention
[0010] FIG. 1A-1D show schematic illustrations of a fiber generated by the present invention.
[0011] FIG. 2 is a schematic illustration of a portion of an electrospinning apparatus according to an embodiment of the invention.
[0012] FIG. 3A-3B show schematic illustrations of a portion of an electrospinning apparatus according to an embodiment of the invention.
[0013] FIG. 4A-4B show schematic illustrations of a portion of an electrospinning apparatus according to another embodiment of the invention.
[0014] FIG. 5A-5B show schematic illustrations of a portion of an electrospinning apparatus according to yet another embodiment of the invention.
[0015] FIG. 6 is a schematic illustration of a yarn-making apparatus according to an embodiment of the invention.
[0016] FIG. 7A-7B comprise photographs of an example of the present invention.
[0017] FIG. 8A-8B show photographs of another example of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] The present invention relates to electrospun fibers, including drug-containing electrospun fibers and yarns described in co-pending U.S. patent application Ser. No. 12/620,334 (United States Publication No. 20100291182), the entire disclosure of which is incorporated herein by reference.
[0019] An example of a fiber produced by the devices and methods of the present invention is shown schematically in FIGS. 1 a and 1 b. Fiber 100 is generally tubular in shape, and is characterized by a length 110 and a diameter 111 . Fibers generated by the devices and methods of the present invention are generally small enough to be useful for implantation to address a wide range of medical applications. As such, the fiber 100 has a diameter that is preferably up to about 20 microns. The length 110 of fiber 100 will vary depending on its intended use, and may range widely from micrometers to centimeters or greater. In a preferred embodiment, fiber 100 includes an inner radial portion 120 and an outer radial portion 130 , as shown in FIGS. 1 c and 1 d. In this preferred embodiment, the total diameter 111 of the fiber is no more than about 20 microns, and the diameter of the outer radial portion is about 1-7 microns larger than the inner radial portion.
[0020] FIG. 2 illustrates one embodiment of the present invention. Apparatus 200 comprises a hollow cylindrical tube 210 having a longitudinal slit 220 along its entire length. A core polymer solution 230 can be introduced into the lumen of tube 210 in a volume sufficient for the surface of the solution to emerge through slit 220 . In one example, tube 210 is 0.5-20 cm in diameter with a wall thickness of 50-5,000 microns. The cylindrical tube 210 is made of a conducting material such as stainless steel, copper, bronze, brass, gold, silver, platinum, and other metals and alloys. Slit 220 preferably has a width sufficient to permit formation of Taylor cones 240 from the surface of the core polymer solution 230 , the width of slit 220 being generally between 0.01 and 20 millimeters, and preferably between 0.1 to 5 millimeters. The length of tube 210 is preferably between 5 centimeters and 50 meters, and more preferably between 10 centimeters and 2 meters.
[0021] In certain alternate embodiments, multiple apparatuses 200 may be placed in rows comprising up to 50 units, either in parallel or end-to-end, with a preference for 10 or fewer units per row. An advantage of using multiple units versus one long unit is better control over the flow of the polymer solutions.
[0022] The core polymer solution 230 preferably has a viscosity of between 10 and 10,000 centipoise, and is more preferably between 500 and 5,000 centipoise. Core polymer solution 230 is preferably pumped through the lumen of tube 210 and slit 220 at rates of between 0.01 and 10 milliliters per hour, more preferably between 0.1 and 2 milliliters per hour per centimeter. A voltage, preferably between 1 and 150 kV, more preferably between 20-70 kV, is applied. The positive electrode of the power supply is preferably connected to the conducting slit-cylinder directly or via a wire, such that a potential difference exists between the slit cylinder and a grounded collector 250 . Grounded collector 250 is preferably placed at a distance between 1 and 100 centimeters from slit 220 and parallel to the axial dimension of tube 210 . Grounded collector 250 is a planar plate of various geometries (e.g. rectangular, circular, triangular, etc.), rotating drum/rod, wire mesh, or other 3D collectors including spheres, pyramids, etc. Upon application of a sufficient voltage, Taylor cones 240 and electrospinning jets 241 will form in the exposed surface of polymer solution 230 , and the jets will flow toward collector 250 , forming homogeneous fibers.
[0023] In certain embodiments of the present invention, the apparatus will include means for co-localizing a sheath polymer solution to the site of Taylor cone initiation, so that core-sheath fibers can be produced. In certain embodiments, such as that illustrated in FIG. 3 , hollow cylindrical tube 210 will be arranged so that slit 220 points downward, and a sheath polymer solution 260 will be applied to the upward-facing external surface of tube 210 so that sheath polymer solution 260 runs down the sides of tube 210 and co-localizes with the core-sheath polymer at sites of Taylor cone and jet initiation 240 , 241 . Once the sheath polymer solution 260 is co-localized with the Taylor cone, it will be incorporated into the jet. The sheath polymer solution 260 is drawn toward and over the core fibers by varying the flow rate and viscosity of the sheath polymer solution 260 , or by incorporating structural features 211 such as grooves, channels, coatings, and textured or smooth surfaces on the outer surface of hollow tube 210 .
[0024] In certain alternate embodiments, as illustrated in FIG. 4 , hollow tube 210 will be partially submerged in a bath 270 containing the sheath polymer solution 260 . The volume of the sheath polymer solution 260 within bath 270 will be set at a level so that the top surface of the sheath polymer solution is at or near the sites of Taylor cone and jet initiation 240 , 241 . As described above, the rate at which sheath polymer solution 260 is drawn into fibers can be controlled by varying the viscosity of sheath polymer solution 260 , or by incorporating structural features 211 on the outer surface of hollow tube 210 such as grooves, channels, coatings and textured or smooth surfaces.
[0025] In still other alternate embodiments, such as the one described in Example 2, infra, the sheath polymer solution 260 can be introduced directly to the sites of Taylor cone and jet initiation 240 , 241 , by using a syringe pump and needle. This method is preferred over previously used coaxial nozzle arrays, as single bore needles are used, reducing the likelihood of clogging.
[0026] In an alternate embodiment of the present invention, three parallel troughs are utilized, as illustrated in FIG. 5 . Apparatus 300 comprises an inner trough 310 and two outer troughs 320 , 330 . The walls 311 , 312 of inner trough 310 are optionally tapered, so that their thickness decreases to zero at the top of inner trough 310 . Inner trough 310 is filled with a solution of core polymer solution 220 , which is pumped through inner trough 310 from the bottom up at rates suitable for electrospinning, generally between 0.1 to 2 milliliters per hour per centimeter, but up to 10 milliliters per hour per centimeter. Alternatively, the solution can be fed in from the sides or a combination of the bottom and sides. Inner trough 310 has a height ranging preferably from 5-10 centimeters and a width sufficient to permit formation of Taylor cones and jets 240 , 241 , which emerge from the surface of core polymer solution 220 , the width of inner trough 310 being generally between 0.01 and 20 millimeters, and preferably between 0.1 to 5 millimeters. Outer troughs 320 , 330 are filled with sheath polymer solutions 260 to heights sufficient for the sheath polymer solution to be drawn into the sites of Taylor cone and jet initiation 240 , 241 . As shown in FIG. 5 b , walls 311 , 312 of inner trough 310 may incorporate a reciprocal periodic wave structure, forming regions of higher and lower width within inner trough 310 , which structure biases the formation of Taylor cones and jets 240 , 241 to regions in which the width of inner trough is locally maximized. The voltage is applied by attaching the positive electrode of the power supply to the inner walls of the trough, which is composed of a metallic conducting material such as stainless steel, copper, bronze, gold, silver, platinum and other alloys.
[0027] In an alternate embodiment, the invention comprises a collector plate configured as a drum 400 , which can be placed into a yarn-spinning apparatus as shown in FIG. 6 . At any point during collection of fibers (prior to initiation, during collection, or after collection initiation), the drum is engaged with a belt that is in turn engaged with a mandrel that can spin in one direction, and free ends of the collected fibers are attached to another drum engaged with another belt that is engaged with a different mandrel which spins in a direction opposite from that of the first mandrel. The resulting yarns can be post-processed into higher-order structures such as ropes by attaching opposite ends of multiple yarns to opposing drums, and spinning them in opposite directions as described above.
[0028] In some embodiments of the invention, the polymers used in the present invention include additives such as metallic or ceramic particles to yield fibers having a composite structure.
[0029] The devices and methods of the present invention may be further understood according to the following non-limiting examples:
Example 1
Formation of Homogeneous Fibers
[0030] Homogeneous fibers made of poly(lactic co-glycolic acid) (L-PLGA) were manufactured in accordance with the present invention. A solution containing 4.5 wt % of 85/15 L-PLGA in hexafluoroisopropanol was pumped into one end of a 10 cm long hollow tube (1 cm diameter) having a 0.4 cm slit of the present invention at a rate of 8 milliliters per hour. A grounded, flat, rectangular collecting plate was placed approximately 15 centimeters from the slit of the cylinder, and a voltage of 25-35 kV was applied, and the resultant fibers were collected on the collecting plate and examined under scanning electron microscopy as illustrated in FIG. 7 b.
Example 2
Formation of Core-Sheath Fibers
[0031] Core-sheath fibers were manufactured in accordance with the present invention, as shown in FIG. 8 a . A rhodamine-containing core solution containing 15 wt % polycaprolactone in a 3:1 (by volume) chloroform:acetone solution was pumped through a hollow cylindrical tube having a slit therethrough at a rate of 10 ml/hour. Jets were formed by applying a voltage of 25 kV. Once the Taylor cones were stable, a syringe pump and needle filled with a fluorescein-containing sheath solution containing 15 wt % polycaprolactone in a 6:1 (by volume) chloroform:methanol solution was placed so that the needle was adjacent to one of the Taylor cones, and the sheath solution was pumped at a rate of 6 ml/hour. To verify the core-sheath structure of the resulting fibers, fluorescence micrographs were obtained which demonstrated that the rhodamine-containing core component was indeed surrounded by the fluorescein-containing sheath component, as shown in FIG. 8 b.
[0032] The present invention provides devices and methods for producing homogeneous and core-sheath fibers. While aspects of the invention have been described with reference to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention. | Devices and methods for high-throughput manufacture of concentrically layered nanoscale and microscale fibers by electrospinning are disclosed. The devices include a hollow tube having a lengthwise slit through which a core material can flow, and can be configured to permit introduction of sheath material at multiple sites of Taylor cone formation formation. | 3 |
BACKGROUND
When a network load balancer receives a packet, the load balancer may select one of multiple devices that are to process the packet. The load balancer may select the processing device based on loads on the devices. The load balancer may send the packet to the selected processing device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates an exemplary load balancing system;
FIG. 1B illustrates exemplary data fragmentation caused by an exemplary load balancer of FIG. 1A according to one implementation;
FIG. 1C illustrates exemplary load balancing performed by the load balancer of FIG. 1A according to another implementation;
FIG. 2 shows an exemplary network in which concepts described herein may be implemented;
FIG. 3 is a block diagram of exemplary components of an exemplary network device of FIG. 2 ;
FIG. 4 is a block diagram of exemplary functional components of an exemplary load balancer device of FIG. 2 ;
FIG. 5A depicts an exemplary Session Initiation Protocol (SIP) packet;
FIG. 5B depicts an exemplary SIP message of FIG. 5A ;
FIG. 5C depicts an exemplary real-time transport protocol (RTP) packet;
FIG. 6 shows exemplary records of an exemplary content identifier database of FIG. 4 ; and
FIG. 7 is a flow diagram of an exemplary process for load balancing based on deep packet inspection.
DETAILED DESCRIPTION
The following detailed description refers to the accompanying drawings. The same reference numbers in different drawings may identify the same or similar elements. As used herein, the term “deep packet inspection” may include inspecting contents (e.g., a payload) of a packet. For example, a router that is examining the layer 3 payload of a packet may be performing deep packet inspection.
As described below, a device may distribute received packets to processing devices based on deep packet inspection. FIGS. 1A through 1C illustrate concepts described herein. FIG. 1A shows an exemplary load balancing system. As shown, load balancing system 100 may include a load balancer device 102 , processing device 104 - 1 , and processing device 104 - 2 (herein as “processing device 104 ” or “processing devices 104 ”).
Load balancer device 102 relays incoming packets to either processing device 104 - 1 or processing device 104 - 2 in accordance with a load balancing scheme (e.g., a packet distribution scheme). Processing device 104 processes packets that are received from load balancer device 102 (e.g., record a piece of data carried by the packet, fetch a web page, perform an e-transaction, etc.).
In system 100 , at processing devices 104 , the results of processing packets whose data is part of the same content may later be organized into a single unit of data. For example, assume that packets that carry audio data of a song arrive at load balancer device 102 ; that load balancer device 102 distributes the packets to processing devices 104 ; and that processing devices 104 record the data from the packets. Once the recordings are complete, a network device (e.g., processing device 104 - 1 , 104 - 2 , or another device (not shown)) may assemble the recordings into a copy of the song. The recordings may be easier to assemble if the data are sequentially recorded at one processing device 104 , rather than fragmented over both processing devices 104 .
FIG. 1B illustrates exemplary data fragmentation caused by load balancer device 102 according to one implementation. Assume that signal packets 112 and 120 provide signaling for the same communication session; that data packets 118 and 124 carry data from the same communication session; that each of packets 112 and 118 includes addresses 114 ; and that each of packets 120 and 124 includes addresses 122 .
When load balancer device 102 receives signal packet 112 , load balancer device 102 associates processing device 104 - 1 with addresses 114 of signal packet 112 , and records the association/assignment in a table 116 (e.g., a database). Load balancer device 102 sends signal packet 112 to processing devices 104 to be recorded.
When data packet 118 (having address 114 ) arrives at load balancer device 102 , load balancer device 102 searches table 116 to identify processing device 104 - 1 that is assigned to addresses 114 , and sends data packet 118 to processing device 104 - 1 . Consequently, signal packet 112 and data packet 118 may be recorded at the same processing device 104 - 1 . In this scenario, there is no data fragmentation.
Assume that toad balancer device 102 receives signal packet 120 . Because signal packet 120 has address 122 different from address 114 , table 116 may fail to identify a processing device. Consequently, load balancer device 102 may assign or associate, possibly a. different processing device, such as processing device 104 - 2 with addresses 122 . Load balancer device 102 sends signal packet 120 to processing devices 104 to be recorded. In this scenario, although packets 112 and 120 may be sent to the same processing devices 104 , processing devices 104 may not recognize that packets 112 and 120 belong to the same session, and store contents of packets 112 and 120 in two fragments.
If data packet 124 , which includes addresses 122 , follows packet 120 into load balancer device 102 , load balancer device 102 may route data packet 124 to processing device 104 - 2 based on the new association between address 122 and processing device 104 - 2 in table 116 . This may cause the data from packets 118 and 124 to be distributed over two different processing devices 104 - 1 and 104 - 2 and result in further fragmentation of the data.
FIG. 1C illustrates exemplary load balancing performed by load balancer device 102 according to another implementation. In this implementation, load balancer device 102 may balance load based on deep packet inspection. This may reduce or eliminate the data fragmentation described above with reference to FIG. 1B .
Assume that signal packets 112 and 120 carry the same content identifier (e.g., the same SIP call ID), since packets 112 and 120 provide signaling for the same communication session.
When load balancer device 102 receives signal packet 112 , load balancer device 102 extracts the content identifier from the payload of signal packet 112 , associates processing device 104 - 1 and addresses 114 with the content identifier, and records the association in a table 130 . Load balancer device 102 then sends packet 112 to processing device 104 - 1 to be recorded.
When data packet 118 arrives at load balancer device 102 , load balancer device 102 searches table 130 , using addresses 114 of data packet 118 as a key. Accordingly, load balancer 102 retrieves the content identifier and identifies processing device 104 - 1 . Consequently, load balancer device 102 sends data packet 118 to processing device 104 - 1 to be recorded.
When load balancer device 102 receives signal packet 120 , load balancer device 102 performs a lookup, in table 130 , using the content identifier as a key. Although addresses 122 of signal packet 120 are different from addresses 114 of packet 112 , by using the content identifier as a key in its lookup, load balancer device 102 still identifies processing device 104 - 1 and sends packet 120 thereto. In contrast to the corresponding scenario described with reference to FIG. 1B , the contents of packets 112 and 120 are recorded in one processing device 104 - 1 .
In FIG. 1C , when load balancer device 102 receives signal packet 120 , in addition to sending signal packet 120 to processing device 104 - 1 , load balancer device 102 replaces the association between addresses 114 and processing device 104 - 1 with an association between addresses 122 and processing device 104 - 1 . Accordingly, when data packet 124 arrives at load balancer device 102 , load balancer device 102 may use addresses 122 as a key to search table 130 and identify processing device 104 - 1 . Hence, load balancer may send packet 124 to processing device 104 - 1 . This allows the data in packets 118 and 124 to be recorded in one processing device 104 - 1 .
FIG. 2 illustrates an exemplary network in which concepts described herein may be implemented. Network 200 may include one or more wired and/or wireless networks that are capable of exchanging information, such as voice, video, documents, multimedia, text, etc. For example, network 200 may include one or more public switched telephone networks (PSTNs) or another type of switched network. Network 200 may also include a number of transmission towers for receiving wireless signals and forwarding the signals toward the intended destination. Network 200 may further include one or more packet switched networks, such as an Internet protocol (IP) based network, a local area network (LAN), a wide area network (WAN), a personal area network (PAN), an intranet, the Internet, or another type of network that is capable of exchanging information.
As shown, network 200 may include user devices 202 - 1 and 202 - 2 (herein “user device 202 ” or “user devices 202 ”), a registrar device 204 , proxy server devices 206 - 1 and 206 - 2 (herein “proxy server device 206 ” or “proxy server devices 206 ”), a signal copy device 208 , a media copy device 210 , a load balancer device 212 , and processing devices 214 - 1 through 214 -M (herein “processing device 214 ” or “processing devices 214 ”). In FIG. 2 , network devices 202 through 214 may communicate via links that are illustrated as solid lines. For simplicity, FIG. 2 does not show other communication links (e.g., communication links between registrar device 204 and proxy server 206 - 2 , between signal copy device 208 and media copy device 210 , etc.) and elements of network, such as routers, bridges, switches, gateways, wireless access points, hubs, etc.
In the following, for simplicity, network devices 202 - 214 are described as applying Session Initiation Protocol (SIP), Session Description Protocol (SDP), and Real-time Transport Protocol (RTP). Depending on the implementation, other communication protocols, such as H.323, Media or Multimedia Gateway Control Protocol (MGCP), etc. may also be applied to the concepts described herein.
User devices 202 may communicate with one another over network 200 . In one implementation, user devices 202 - 1 and 202 - 2 may host or operate as SIP clients (e.g., SIP phones). The SIP clients may create, send, and/or receive SIP messages. In addition, the SIP clients may send or receive a media stream (e.g., RTP stream). To allow other devices in network 200 to locate the SIP clients, the SIP clients may register at registrar device 204 .
Registrar device 204 may store information about SIP clients. In addition, registrar device 204 may provide the stored information to other devices in network 200 . Proxy server device 206 may forward a SIP message to its intended destination. In addition proxy server device 206 may locate SIP clients and provide information about the SIP clients to other network devices or components (e.g., a software component).
Signal copy device 208 may create a copy of a signal packet (e.g., a packet that includes signaling information (e.g., a SIP packet)) between proxy server devices 206 and provide the copy to processing device 214 via load balancer device 212 .
Media copy device 210 may copy packets of a media stream between user devices 202 and provide the copies to processing device 214 via load balancer device 212 . By exchanging SIP messages, user devices 202 may establish a RTP channel between one another. The RTP channel may then be used to send or receive the media stream (e.g., voice data, video, etc.) between user devices 202 .
Load balancer device 212 may receive copies of signal packets and a media stream from signal copy device 208 and media copy device 210 , respectively. In addition, load balancer device 212 may select one of processing devices 214 and send the received copies to the selected processing device 214 .
Processing device 214 may receive copies of signal packets and a media stream and process them. In one implementation, processing device 214 may record the copies in the order that they are received, for further processing or use.
Depending on the implementation, network 200 may include additional, fewer, different, or different arrangement of devices than those illustrated in FIG. 2 . For example, in one implementation, network 200 may include redirect server devices, additional user devices, additional proxy server devices, additional registrar devices, etc. In another example, the functionalities of one or more devices 202 - 214 may be integrated into other devices 202 - 214 . For example, registrar device 204 may be combined with proxy server device 206 - 1 .
FIG. 3 is a block diagram of an exemplary network device 300 , which may correspond to one or more of devices 202 - 214 . As shown, network device 300 may include a processor 302 , memory 304 , storage unit 306 , input component 308 , output component 310 , network interface 312 , and communication path 314 . In different implementations, network device 300 may include additional, fewer, different, or different arrangement of components than the ones illustrated in FIG. 3 . For example, network device 300 may include line interfaces, such as interfaces for receiving and forwarding data.
Processor 302 may include a processor, a microprocessor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), and/or other processing logic capable of controlling network device 300 . Memory 304 may include static memory, such as read only memory (ROM), and/or dynamic memory, such as random access memory (RAM), or onboard cache, for storing data and machine-readable instructions (e.g., programs, scripts, etc.). Storage unit 306 may include a floppy disk, CD ROM, CD read/write (R/W) disc, and/or flash memory, as well as other types of storage devices for storing data and/or machine-readable instructions (e.g., a program, script, etc.).
Input component 308 and output component 310 may provide input and output from/to a user to/from network device 300 . Input/output components 308 and 310 may include a display screen, a keyboard, a mouse, a speaker, a microphone, a camera, a DVD reader, Universal Serial Bus (USB) lines, and/or other types of components for converting physical events or phenomena to and/or from signals that pertain to network device 300 .
Network interface 312 may include a transceiver (e.g., a transmitter or receiver) for network device 300 to communicate with other devices and/or systems. For example, via network interface 312 , network device 300 may communicate over a network, such as the Internet, an intranet, a terrestrial wireless network (e.g., a WLAN, WiFi, WiMax, etc.), a satellite-based network, etc. Network interface 312 may include a modem, an Ethernet interface to a LAN, and/or an interface/connection for connecting network device 300 to other devices (e.g., a Bluetooth interface).
Communication path 314 may provide an interface through which components of network device 300 can communicate with one another.
FIG. 4 is a block diagram of functional components of load balancer device 212 . As shown, load balancer device 212 may include load balancing logic 402 , deep packet inspection (DPI) logic 404 , and a content identifier database 406 . For simplicity, FIG. 4 does not show other components, such as an operating system, device drivers, etc. Depending on the implementation, load balancer device 212 may include additional, fewer different, or different arrangement of functional components than those illustrated in FIG. 4 .
Load balancing logic 402 may distribute packets received from signal copy device 208 and media copy device 210 to processing devices 214 based on a load balancing scheme. In some implementations, the load balancing scheme may include processing at least two different types of packets, signal packets and data packets.
When load balancing logic 402 receives a signal packet (e.g., a SIP packet) that belongs to a particular call/session between user devices 202 , load balancing logic 402 may perform a deep packet inspection of the packet. Via deep packet inspection logic 404 , load balancing logic 402 may extract a content identifier (e.g., a SIP call identifier) in the payload of the signal packet.
If the content identifier is not in content identifier database 406 , load balancing logic 402 may associate a processing device 214 (selected based on load balancing criteria (e.g., processing load on processing devices 214 )), a pair of network addresses (e.g., source IP address and destination IP address) and the content identifier. The network addresses may be provided in the header of the received signal packet. Load balancing logic 402 may store the associations in content identifier database 406 .
If the content identifier is found in content identifier database 406 , load balancing logic 402 may still associate a pair of network addresses (e.g., source and destination IP addresses) provided in the header of the signal packet with the content identifier, and consequently, with processing device 214 previously associated with the content identifier. Load balancing logic 402 may overwrite, with the new association, any old association between the content identifier and other network addresses. Subsequently, load balancing logic 402 may send the signal packet to the processing device 214 .
When load balancing logic 402 receives a data packet (e.g., a copy of a packet in a media stream between user devices 202 ), load balancer device 212 may obtain a pair of network addresses (e.g., source IP address and destination IP address) provided in the header of the received data packet. Furthermore, using the addresses, load balancing logic 402 may perform a lookup of processing device 214 that is associated with the network addresses. Load balancing logic 402 may send the data packet to the identified processing device 214 .
Deep packet inspection logic 404 may examine contents (e.g., the payload) of a packet (e.g., a signal packet (e.g., a SIP packet)), extract a piece of information within the contents, and/or identify the piece of information within the contents. For example, deep packet inspection logic 404 may extract a SIP call identifier from within the payload of a SIP packet on behalf of load balancing logic 402 .
FIG. 5A depicts an exemplary SIP packet 500 . Deep packet inspection logic 404 may examine SIP packet 500 to extract a content identifier (e.g., a SIP call ID). As shown in FIG. 5A , SIP packet 500 may include an IP header 504 , a Transmission Control Protocol (TCP) header 506 , and a SIP message 508 . For simplicity, packet 500 does not show other components of packet 500 .
IP header 504 and TCP header 506 may include information for a network to provide reliable transport services to SIP packet 500 . IP header 504 and TCP header 506 may include, for example, source and destination IP addresses, source and destination port numbers, a packet sequence number, etc.
SIP message 508 may include a type of message under the SIP, such as, for example, a REGISTER message, INVITE message, ACK message, CANCEL message, BYE message, OPTIONS message, error message, etc. FIG. 5B shows an exemplary SIP message 508 (e.g., INVITE message). As shown, SIP message 508 may include a SIP message header 510 and a SIP message body 512 .
SIP message header 510 may include a call identifier (call ID), information about user agents that are to send/receive SIP packet 500 , an indication of the type of SIP message 508 , an indication of the type of information in the body of SIP message 508 , etc.
SIP message body 512 may include, for example, a SDP message that describes a RTP media stream. Based on the SDP message, user devices 202 - 1 may send or receive a RTP media stream. The media stream may include RTP packets. In FIG. 2 , media copy device 210 may send copies of RTP packets from the media stream to load balancing device 212 .
FIG. 5C depicts an exemplary RTP packet 520 . As shown, RTP packet 520 may include an IP header 522 , a User Datagram Protocol (UDP) header 524 , and a RTP message 526 . IP header 522 and UDP header 524 may include information for a network to provide a transport service to RTP packet 520 . RTP message 526 may include a portion of the media stream. For simplicity, RTP packet 520 does not show other information that RTP packet 520 may include.
Returning to FIG. 4 , content identifier database 406 may include one or more records pertaining to content identifiers. Content identifier database 406 may be implemented as a table, list, hash table, etc. FIG. 6 shows exemplary records of content identifier database 406 . As shown, content identifier database 406 may include records 602 - 1 through 602 -R (herein “records 602 ” or “record 602 ”).
As further shown, each record 602 may include a content identifier field 604 , an addresses field 606 , and a processing device identifier field 608 . Depending on the implementation, record 602 may include additional, fewer, different, or different arrangement of fields than those illustrated in FIG. 6 .
Load balancing logic 402 may create and/or modify each of fields 604 - 608 in record 602 when load balancing logic 402 receives a signal packet. In addition, based on the content identifier provided in the signal packet, load balancing logic 402 may look up record 602 to identify processing device 214 to which a data packet or the signal packet is to be sent.
Content identifier field 604 may include an identifier that a signal packet carries in its payload. The identifier may be associated with content whose portions are included in data packets of a media stream. For example, in one implementation, a signal packet may include an SIP call ID as part of SIP message 508 . The SIP call ID may identify a particular communication session between user agents that are hosted on user devices 202 .
Addresses field 606 may include a source address and a destination address of a signal packet received by load balancing logic 402 .
Processing device identifier field 608 may include an identifier that is associated with processing device 214 that load balancing logic 402 has selected to process signal packets and data packets. The payloads of the data packets may include content identified by the content identifier in content identifier field 604 .
FIG. 7 is a flow diagram of an exemplary process 700 for load balancing based on deep packet inspection. Process 700 may begin when load balancing device 212 receives a packet (block 702 ).
Load balancing device 212 may determine whether the packet is a RTP packet (block 704 ). For example, load balancing logic 402 may determine whether the packet is a RTP packet based on deep packet inspection (e.g., by determining whether the payload of the packet includes a RTP message).
If the packet is an RIP packet (block 704 —YES), load balancing logic 402 may look up record 602 whose addresses (e.g., data stored in addresses field 606 ) matches the network addresses of the RIP packet (block 706 ). The record 602 may identify, in processing device identifier field 608 , processing device 214 that is assigned to the content identifier. Load balancing device 212 may send the RIP packet to the identified processing device 214 (block 708 ) to be recorded.
If the packet is not an RIP packet (block 704 —NO), load balancer device 212 may determine whether the packet is a SIP packet (block 710 ) based on deep packet inspection. If the packet is not a SIP packet (block 710 —NO), load balancer device 212 may perform an implementation dependent action (block 712 ) (e.g., notify a network operator of an error, follow an instruction specified in the packet, communicate with another device, etc.).
If the packet is a SIP packet (block 710 —YES), load balancer device 212 may extract a call identifier from the SIP packet (block 714 ). Via deep packet inspection, load balancer device 212 may extract the call identifier from SIP message 508 in the SIP packet.
Load balancer device 212 may look up the call identifier in content identifier database 406 . If record 602 with the matching call identifier is found (block 716 —YES), load balancer device 212 may send the SIP packet to processing device 214 that is identified by processing device identifier field 608 in record 602 (block 720 ). In addition, load balancer device 212 may update record 602 , if necessary, with addresses of the SIP packet (e.g., the addresses of the SIP packet is not the same one in record 602 ).
Otherwise (block 716 —NO), load balancer device 212 may create a new record 602 (block 718 ). Content identifier field 604 of new record 602 may include the content identifier extracted from the SIP packet (see block 714 ). Addresses field 606 of new record 602 may include source and destination addresses that are provided in the header of the SIP packet. Processing device identifier field 608 may include an identifier (e.g., a network address, a domain name, etc.) of processing device 214 that load balancing device 214 has selected for processing signal packets and data packets. The signal packets may bear the content identifier. The data packets may include headers whose addresses match the addresses provided in addresses field 606 of new record 602 .
In selecting particular processing device 214 , load balancer device 212 may weigh several factors. The factors may include, for example, for each processing device 214 , processor utilization, storage utilization (e.g., load balancer 212 may not select processing device 212 without space on its storage unit 306 ), memory utilization, network traffic, etc. When processing device 602 receives the packet (e.g., RTP packet or SIP packet) from load balancer device 212 , processing device 602 may record information provided by the packet (e.g., header information, data in its payload, etc.).
In the foregoing description, load balancing device 212 may select processing device 214 to process packets that are associated with a particular content identifier. By sending packets that are associated with the particular content identifier to the same processing device 214 , load balancing device 212 may avoid fragmenting data that belongs to a whole over several processing devices 214 . This may allow the data to be readily reassembled to recover the whole.
The foregoing description of implementations provides illustration, but is not intended to be exhaustive or to limit the implementations to the precise form disclosed. Modifications and variations are possible in light of the above teachings or may be acquired from practice of the teachings.
For example, while series of blocks have been described with regard to an exemplary process illustrated in FIG. 7 , the order of the blocks may be modified in other implementations. In addition, non-dependent blocks may represent acts that can be performed in parallel to other blocks.
It will be apparent that aspects described herein may be implemented in many different forms of software, firmware, and hardware in the implementations illustrated in the figures. The actual software code or specialized control hardware used to implement aspects does not limit the invention. Thus, the operation and behavior of the aspects were described without reference to the specific software code—it being understood that software and control hardware can be designed to implement the aspects based on the description herein.
Further, certain portions of the implementations have been described as “logic” that performs one or more functions. This logic may include hardware, such as a processor, a microprocessor, an application specific integrated circuit, or a field programmable gate array, software, or a combination of hardware and software.
No element, act, or instruction used in the present application should be construed as critical or essential to the implementations described herein unless explicitly described as such. Also, as used herein, the article “a” is intended to include one or more items. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise. | A device may receive a packet, determine a content identifier of the packet, identify a first processing device that has processed part of content associated with the content identifier, send the packet to the first processing device when the first processing device is identified, select a second processing device among a plurality of processing devices when the first processing device is not identified, and send the packet to the second processing device. | 7 |
RELATED APPLICATIONS
This application is a continuation of U.S. Ser. No. 10/153,373 filed May 22, 2002, now U.S. Pat. No. 6,715,642, the contents of which are incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to blending and dispensing devices. More particularly, the present invention relates to blending and dispensing devices for liquid compositions including, among other products, various shades of liquid cosmetic compositions.
BACKGROUND OF THE INVENTION
Colored liquid cosmetics such as lipstick, lip gloss, tinted creme, foundation, eyeliner, and nail polish are desired in numerous shades to fit the preferences of various consumers. For example, more than 20 shades of liquid foundation may be popular in a season and desired to suit different skin tones that exist in the public. Thus, it is necessary that foundation manufacturers mix more than 20 shades of foundation in manufacturing plants to satisfy the public's desires. It is also necessary that a consumer purchase a separate bottle of each desired shade.
The prior art suggests how the cosmetics industry might eliminate the need to purchase separate bottles of foundation for each shade a consumer desires. In particular, a consumer may mix his/her personal shade of colors at home by using one of the prior art multi-chambered dispensers. Past multi-chambered cosmetic dispensers generally utilize a mechanical pump means. Examples of typical multi-chambered fluid dispenser are disclosed in U.S. Pat. Nos. 5,848,732 and 3,760,986. U.S. Pat. No. 3,760,986 discloses a multi-chambered dispenser that is operated by a positive displacement pump. The dispenser comprises separate non-communicating compartments and a tube extending from each compartment into a chamber in the nozzle head. The positive displacement pump has two spaced pistons and two spring-loaded ball checks for closing the connection between the chamber and the depending tube in each chamber. As the user depresses the pump, the spring-loaded ball is displaced so that fluid from each compartment can separately pass into the chamber and out the nozzle head. U.S. Pat. No. 5,848,732 discloses a similar mechanical multi-chambered dispenser with a positive displacement pump. However, the dispenser disclosed in U.S. Pat. No. 5,848,732 utilizes a mixing apparatus having a manual adjuster for changing the amount of medium dispensed from each compartment into a mixing chamber. After the medium is mixed, the medium exits the dispenser.
One problem with past multi-chambered dispensers is that the dispenser is a pump that typically comprises a plastic piston and a spring-loaded ball which both tend to wear out or break after continued use, causing the dispenser to malfunction. Another problem with past multi-chambered dispensers is that mechanical pumps limit a user to fixed increments of product from each chamber of the dispenser. In relation, the manually operated mechanical pumps do not successfully dispense micro-liter volumes of liquid from each compartment or dispense precise doses of product after repeated use. Thus, if the past multi-chambered dispenser is used to mix colored products, one dispenser would not achieve every color in the visible color spectrum. Further, a pump style dispenser can be messy because a user has to pour liquid foundation or other fluids into the chambers each time the fluids are depleted. The conventional dispensers also do not effectively use up all of the foundation in the dispensers because the tubes in which the foundation is pulled up into do not pull fluid off of the dispenser walls.
Therefore, there remains a need to provide a dispenser for dispensing liquid cosmetic compositions that is cost effective, durable, and dispenses doses of product in non-limiting and accurate increments. There also remains a need to provide a dispenser that dispenses an infinite number of shades of cosmetics.
SUMMARY OF THE INVENTION
The present invention overcomes the shortcomings associated with previous multi-chambered dispensers by providing a multi-chambered dispenser for dispensing customized fluid compositions using ink jet printing technology. The present invention includes a housing defining a dispensing orifice, a device to specify the customized liquid formula, a central processing system including stored formulas, a power source, multiple cartridges, and at least one ink jet head for dispensing programmed volumes of the customized liquid formula. In one embodiment, the dispenser is made to dispense customized shades of liquid foundation. Utilizing ink jet printing technology for dispensing liquid cosmetic compositions is a surprising aspect of the present invention because ink that is used in ink jet printers is much more fluid than typical liquid cosmetic compositions. It was believed that the rheology of cosmetic fluids, such as liquid foundation, would not properly flow through the ink jet cartridges.
These and other aspects and advantages of the invention will be better understood upon review of the following description, pending claims, and accompanying sheets of drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front planar view of one embodiment of the dispenser.
FIG. 2 is a back view of the dispenser in FIG. 1 .
FIG. 3 is a bottom view of the dispenser in FIG. 1 .
FIG. 4 is an exploded view of the dispenser in FIG. 1 .
FIG. 5 is a schematic cross-sectional view of a cartridge, flow path, and piezoelectric ink jet head.
FIG. 6 is a schematic cross-sectional view of a solenoid ink jet head.
FIG. 7 is a schematic cross-sectional view of a dual valve solenoid-piezo ink jet head system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention uses ink jet printing technology to dispense a variety of compositions including, but not limited to, fluids containing vitamins, minerals, or fluoride for use in connection with water treatment systems, liquid cosmetics such as lipstick, lip gloss, eyeliner, and blush; fragrances; personal care products such as lotions, creams, moisturizers, and sunscreens; and home care products such as multi-purpose cleaners and air fresheners. The ink jet head may use a magneto-restrictive alloy, thermal, solenoid, or piezoelectric technology. For purposes of illustrating the present invention in detail, an exemplary piezoelectric system for custom formulating liquid foundation will be described. Piezoelectric technology uses piezo crystals which receive a tiny electric charge causing the crystals to vibrate. At one instance, the crystal pulls back to allow fluid into the reservoir. At another instance, the crystal fires back into its original position exerting a mechanical pressure on the fluid which forces a tiny amount of fluid out of the nozzle. The typical ink jet head forces out small droplets of fluid, generally between 50 to 60 microns in diameter.
Now referring to FIG. 1 , a perspective view of one embodiment of the multi-chambered dispenser 2 is shown. The dispenser 2 has a cap 4 and a power button 6 . FIG. 2 shows the back view of the dispenser. The dispenser has a device or control panel 8 for specifying a shade of liquid cosmetic. The control panel 8 may include several buttons that function to increase or decrease the amount of liquid that is dispensed from the cartridges 14 a – 14 d . A removable cover or door 10 may partially or wholly cover the control panel 8 . FIG. 3 shows the bottom view of the dispenser 2 showing a dispensing port 12 .
Referring to FIG. 4 , the multi-chambered dispenser 2 houses four cartridges 14 a , 14 b , 14 c , 14 d that contain a different color of liquid foundation. Each cartridge 14 a – 14 d may hold about 1 ml to about 15 ml of liquid foundation. The cartridges 14 a – 14 d are pressurized so the liquid foundation contained therein can easily pass out of the cartridges 14 a – 14 d and into its corresponding flow path 16 shown in FIG. 5 .
FIG. 5 is a schematic drawing of a piezoelectric system showing only one cartridge 14 a and corresponding flow path 16 and a piezoelectric ink jet head 40 . Although the four cartridges 14 a – 14 d in FIG. 4 are not shown, this schematic drawing generally applies to each cartridge 14 a – 14 d . Each flow path 16 empties into a corresponding chamber 42 . The cartridges 14 a may also include a plunger 20 for assisting in dispensing liquid from the cartridge to the flow path 16 . Preferably, pressurized gas is disposed in a compartment 18 behind the plunger 20 to apply a force to the plunger 20 . In some applications, the pressurized gas can be replaced by a spring or other conventional biasing mechanism. Alternatively, the cartridge 14 a may use capillary action to move the liquid foundation into the ink jet head 40 . The cartridge receiving end 22 of the flow path 16 may include a rod shaped plug 24 that breaks the cartridge seal when the cartridge 14 a is coupled to the receiving end 22 of the flow path 16 as well as an o-ring 26 . O-ring 26 surrounds the outside of the cartridge to prevent the liquid from leaking out around the edge of the cartridge 14 a . The seal may be a spring-loaded ball 28 as shown in FIG. 5 , a conventional foil seal, or natural surface tension. The cartridge 14 a may be threaded or otherwise coupled to the receiving end 22 of the flow path 16 .
In another embodiment of the present invention, one cartridge 14 a may feed into multiple ink jet heads 40 . For example, each cartridge 14 a – 14 d might have three flow paths 16 , each leading into a separate ink jet head 40 (not shown). These multiple ink jet heads 40 are configured such that the colors of the liquid foundation are interlaced. Because ink jet print heads dispense extremely small dots of color onto a printing surface, typically between 50 and 60 microns in diameter (which is smaller than the diameter of a human hair), dispersal of interlaced colors of foundation in the palm of a user's hand will provide a more blended appearance than a non-interlaced pattern. An example of an interlaced pattern is illustrated below:
White
Black
Yellow
Black
White
Red
Yellow
Red
White
In yet another embodiment, the orifice 46 of each ink jet head is angled such that each foundation color collides with another color upon dispersal out of the orifice 46 (not shown). In still yet another embodiment, the orifice 46 of ink jet head 40 is fluidly connected to a corresponding exit flow path. Each exit flow path merges into a single mixing chamber allowing the colors to be mixed before exiting the dispensing port 6 (not shown).
It will be apparent to those skilled in the art that depending on the type of composition dispensed from the present device, the number of cartridges will vary to satisfy the various shade, nutrients, sunscreen, or fragrances desired for that liquid composition. For example, if a dispenser for customized levels of sunscreen protection is manufactured, there may be a cartridge for the UVA/UVB protectant composition and a cartridges for the other ingredients. The dispersal of UVA/UVB would differ for each level of sunscreen a user desires. Another example is water treatment systems having the present invention to add desired vitamins and minerals. A separate cartridge may exist for the various vitamins and minerals so a user can choose a desired formula for the water he/she obtains from the water treatment system. For liquid foundation, the colors that are necessary to achieve the array of shades to match various skin tones are red, white, yellow, and black. Preferred ratios of the red, white, yellow, and black foundation pre-mixes for exemplary shades are as follows. All percentages are by total weight unless otherwise indicated.
TABLE 1 Desired Amount of Foundation Pre-Mix Desired Shade White Red Yellow Black Ivory 95.50% 0.90% 3.60% 0.00% Fresh Bisque 89.87% 2.43% 6.40% 1.30% Natural 84.58% 3.42% 9.90% 2.10% Honey Crème 84.20% 3.60% 10.60% 1.60% True Beige 80.29% 5.31% 12.50% 1.90% Mocha 26.17% 21.09% 40.47% 12.27% Deep Mahogany 0.82% 26.98% 38.75% 33.45%
Formula examples for the foundation pre-mixes are shown in Table 2.
TABLE 2
White Pre-mix (Water in Cyclomethicone)
In The Oil Phase
Cyclomethicone
11.75
Cyclomethicone (and)
10.00
Dimethicone Copolyol
Sorbitan Trioleate
0.20
Tocopheryl Acetate
0.25
Acrylates Copolymer
10.00
(and) Cyclomethicone
Colorant Section
Iron Oxides, Titanium Dioxide (and)
10.00
Magnesium Myristate
Active Ingredient
Zinc Oxide (and)
3.0
Dimethicone,
Hydrophobic Ultra Fine
Phenylbenzimidazole
3.00
Sulfonic Acid
Triethanolamine
1.93
Methylparaben
0.20
Propylparaben
0.06
Glycerin, 96%
2.00
Green Tea Extract in
1.00
Butylene Glycol
Lactobacillus/Acerola Cherry
1.00
Ferment
Alpha-Glucan
2.00
Oligosaccharide
PEG-150/Decyl
1.00
Alcohol/SMDI Copolymer in
Propylene Glycol and Water
Benzyl Alcohol
1.00
In the Water Phase
Water, Purified
41.61
TOTAL
100%
Red Pre-Mix (Suspension)
DI Water
79.60%
Gellan Gum (Kelco Gel) (Monsanto)
0.20
Red Iron Oxide (RND-DC00)
20.00
49.1% solids (Sun Chemical)
Diazolidinyl Urea (and) Iodopropynyl
0.20
Butylcarbamate
TOTAL
100%
Yellow Pre-Mix (Water in Oil Emulsion)
In the Water Phase
Purified Water
49.10%
Sodium Chloride
0.50
Disodium EDTA
0.20
Diazolidinyl Urea and Iodopropynyl
0.20
Butylcarbamate
Colorant Section
Yellow I.O./Isononyl Isononanoate/
14.81
Isopropyl Titanium
Triisostearate (Kobo)
In the Oil Phase
PEG-30 Dipolyhydroxystearate
3.00
Polyglyceryl-2 Triisostearate
2.00
Isononyl Isononanoate
30.19
TOTAL
100%
Black Pre-Mix (Oil in Water Emulsion)
In the Water Phase
DI Water
66.73%
Disodium EDTA
0.15
Glycereth-26
3.00
Xanthan Gum
0.15
In the Oil Phase
Capric/Caprylic Triglycerides
5.10
Isononyl Isononaoate
5.10
Polyglyceryl-2 Triisostearate
1.82
Polysorbate 60
1.75
Colorant
Iron Oxide and Isononyl Isononanoate and
16.00
Titanium Triisostearate (Kobo)
Diazolidinyl Urea and
0.20
Iodopropynyl Butylcarbamate
TOTAL
100%
For the typical foundation in the medium range of shades, the most dominant color is white. Although it takes white, yellow, red and black to permit the system to make all shades, most shades are predominantly white. If four cartridges of equal volume containing foundations of white, yellow, red and black were used to formulate the most common shades, white would be depleted very rapidly with black far outlasting the other colors. To account for this, a manufacturer may premix white with the other colors in an inverse ratio to frequency of use. For example, white would be 100% white, yellow would be approximately 50% white and 50% yellow, red would be 35% red and 65% white, and black would be 20% black and 80% white. In this way, a fairly even use up rate can be achieved for all colors.
Still referring to FIG. 5 , when a user of the present invention uses the control panel 8 to input a formula comprising a ratio of each foundation from the cartridge, the formula is received by a microprocessor (“CPU”) 30 . The CPU 30 processes the inputted information and controls the amount of power generated from the power source 32 in activating the ink jet head 40 . Fluid in the chamber 42 of the ink jet head 40 is subsequently dispelled by a change in the momentum of a momentum transferring device such as a piezo crystal 44 which is opposite the orifice 46 of the ink jet head 40 . This abrupt change in momentum is conferred to the static liquid within the chamber 42 causing it to assume this momentum and propel from the orifice 46 . A typical orifice of an ink jet head is about 0.002 inches in diameter. The orifice 46 of an ink jet head for dispensing liquid foundation is preferably about 0.007 inches to about 0.008 inches in diameter. Further, due to the rheology of liquid foundation, it is preferable to incorporate more than one momentum transferring device to assist in propelling fluid out of the chamber 42 . The size of the orifice 46 and the use of multiple momentum transferring devices are distinctions in the present invention from conventional ink jet technology. This momentum can be conferred by a thermal system, solenoid actuator, piezo crystal or magneto-restrictive alloy. Any combination of the aforementioned momentum transferring devices can be employed in the present invention.
FIG. 5 is a piezoelectric ink jet head 40 for the present invention and uses a piezo crystal 44 . The ink jet head 40 includes a piezo crystal 44 that reacts to an electrical impulse communicated through the CPU 30 by the power source 32 . When the piezo crystal 44 receives the electrical impulse, the impulse reconfigures the piezo crystal 44 . The continual reconfiguration results in the piezo crystal 44 oscillating up and down. The piezo crystal 44 may oscillate at about 2,000 Hertz via electrical impulse from the power source 32 . The liquid foundation enters the ink jet head through a one way path on the uppermost layer of the piezo crystal 44 . A flexible film 48 may be provided near the entry of the chamber 42 of the ink jet head 40 to assist in controlling the flow of liquid foundation through the flow path 16 and chamber 42 until it reaches the orifice 46 . The force of the piezo crystal 44 while oscillating in a downward direction assists in transferring the liquid foundation out the orifice 46 of the ink jet head 40 . The piezo crystal 44 in this embodiment acts as the momentum transferring device.
Because the fluid is not being actively pumped from a nozzle, measuring the quantity of dispensed fluid is preferably not achieved by using a flow meter. Rather, in a preferred embodiment, metering relies on a calculation of the volume of the chamber 42 in relation to the number of times it is struck by the momentum transferring device. Some work may go into making sure that liquids of varying rheology consistently dispense with a fixed volume. Once this volume is known, one can achieve a desired ratio of liquids simply by controlling the oscillations of the momentum transferring device.
In a preferred embodiment, the liquid foundation dispenses from the orifice 46 in the form of spherical droplets of finite volume. In a preferred embodiment, there are approximately 50,000 drops that total approximately 0.1 ml for each cycle or for each time a user activates the dispenser. Exemplary drops for each pre-mix foundation and volume of premix per drop for sample colors are shown in Table 3. This table represents values achieved in a preferred embodiment. Droplet size may vary from application to application depending on the characteristics of the ink jet head (e.g. ink jet orifice diameter) and the dispensed liquid (e.g. rheology and viscosity). The values in Table 3 are achieved by an enlarged ink jet having an orifice diameter of about 0.007 to about 0.008 inches.
TABLE 3
White
Red
Yellow
Black
Desired Shade
Drops
Vol.
Drops
Vol.
Drops
Vol.
Drops
Vol.
Ivory
47,750
0.0955
450
0.0009
1,800
0.0036
0
0.0
Fresh Bisque
44,935
0.0899
1,215
0.0024
3,200
0.0064
650
0.0013
Mocha
13,085
0.0262
10,545
0.0211
20,235
0.0405
6,135
0.0123
Dk. Mahogany
410
0.0008
13,490
0.0270
19,375
0.0388
16,725
0.0335
Other types of ink jet head systems may be employed for the present invention. FIG. 6 shows a single solenoid ink jet head 40 b . In this embodiment, the momentum transferring device is a solenoid actuator 44 b . The electrical impulse from the power source 32 activates a coil 50 that generates a magnetic field, causing the solenoid actuator 44 b to draw into the coil 50 . A flexible film 48 b may be provided near the entry of the chamber 42 b of the ink jet head 40 b to assist in controlling the flow of liquid foundation through the flow path 16 b and the chamber 42 b until it reaches the orifice 46 b . When the solenoid actuator 44 b releases from the coil 50 , the solenoid actuator 44 b assists in forcing the liquid foundation out of the orifice 46 b.
FIG. 7 shows a dual valve solenoid-piezo embodiment of an ink jet head 40 c . In this embodiment, a piezoelectric ink jet head 40 is used in combination with a solenoid ink jet head 40 b . The liquid foundation flows into the solenoid ink jet head 40 b and then into the piezoelectric ink jet head 40 for final momentum out of the orifice 46 . Similarly, other multi valve ink jet systems can be employed for the present invention. One with ordinary skill in the art will appreciate that any combination of thermal, piezo, solenoid, and magneto-restrictive alloy may be incorporated into the ink jet head.
It is envisioned that the present invention is adapted to be connected to a stand alone or remote computer. Formula information may be stored in the computer's hardware, software, or a website set up for the current dispenser. It is also contemplated that the computer having the stored formula information may be a colorimeter or a spectrophotometer. The dispenser may have a plug-in for hooking the computer up to the dispenser, such as a USB port, serial port, parallel port or other communications port. In operation, the user might choose a shade using the computer which would then download the particular formula into a CPU in the dispenser for immediate dispensing of the desired shade. The computer may include a database of pre-created formula or may create the formula in real time through user interaction. The computer may also permit the user to directly enter a formula. The dispenser CPU may include software for converting formulae received from the computer into ink jet head instructions. Alternatively, the computer may convert the formulae into ink jet head instructions that are transmitted to and executed by the dispenser CPU.
Additionally, it is envisioned that the present invention can be programmed by a personal data assistant using infrared technology whereby the user can input the desired formula into the personal data assistant and transmit that data through an infrared receiving port of the multi-chambered dispenser.
While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for the purpose of illustration, it will be apparent to those skilled in the art that the invention is susceptible to alteration and that certain other details described herein can vary considerably without departing from the basic principles of the invention. | The present invention is directed to a multi-chambered dispenser for blending and dispensing a customized liquid product such as a liquid cosmetic foundation. The dispenser includes a device for selecting a customized liquid formula; a plurality of cartridges separately containing pre-mix compositions for the customized liquid product; at least one ink jet head in fluid communication with the cartridges; a central processing unit for processing the customized liquid formula and activating the ink jet head; whereby the ink jet head dispenses the pre-mix compositions in accordance with the customized liquid formula to provide a customized liquid product. | 0 |
FIELD OF TECHNOLOGY
[0001] The following relates to connectors used in coaxial cable communication applications, and more specifically to coaxial connectors having features for sealing against environmental contaminants, facilitating effective attachment to a corresponding interface port, and improving the efficiency of structures and processes for attaching the connectors to coaxial cables.
BACKGROUND
[0002] Broadband communications have become an increasingly prevalent form of electromagnetic information exchange and coaxial cables are common conduits for transmission of broadband communications. Coaxial cables are typically designed so that an electromagnetic field carrying communications signals exists only in the space between inner and outer coaxial conductors of the cables. This allows coaxial cable runs to be installed next to metal objects without the power losses that occur in other transmission lines, and provides protection of the communications signals from external electromagnetic interference. Connectors for coaxial cables are typically connected onto complementary interface ports to electrically integrate coaxial cables to various electronic devices and cable communication equipment. Connection is often made through rotatable operation of an internally coupling member of the connector about a corresponding externally threaded interface port. Fully tightening the threaded connection of the coaxial cable connector to the interface port helps to ensure a ground connection between the connector and the corresponding interface port. However, often connectors are not properly tightened or otherwise installed to the interface port and proper electrical mating of the connector with the interface port does not occur. Moreover, when attached to an interface port, common connectors are often still susceptible to the unwanted introduction of environmental contaminants into the connector. In addition, common connectors often utilize cumbersome and/or costly components and installation processes associated with attaching the connectors to coaxial cables. Hence a need exists for an improved connector having structural features that facilitate efficient connection of the connector to an interface port, that help prevent the entry of unwanted environmental contaminants into the coaxial cable connector, and that improve cost and effectiveness with relation to how the connector attaches to a coaxial cable.
SUMMARY
[0003] A first aspect of the present invention relates to a coaxial cable connector comprising a connector body; a post, engageable with the connector body; a coupling member, axially rotatable with respect to the connector body, the coupling member having a first end and opposing second end; an outer sleeve engageable with the coupling member, the sleeve configured to rotate the coupling member; and a compression portion structurally integral with the connector body, wherein the compression portion is configured to break apart from the body when axially compressed.
[0004] A second aspect of the present invention relates to a coaxial cable connector comprising; a connector body; a post engageable with connector body; a coupling member, axially rotatable with respect to the connector body, the coupling member having a first end and opposing second end portion; a sealing element attached to the coupling member, wherein the sealing element prevents ingress of environmental elements proximate the first end of the coupling member; and an outer sleeve engageable with the coupling member, the sleeve configured to rotate the coupling member.
[0005] A third aspect of the present invention relates to a coaxial cable connector comprising: a connector body; a post engageable with connector body; a coupling member, axially rotatable with respect to the connector body, the coupling member having a first end and opposing second end; a sealing element attached to the coupling member, wherein the sealing element prevents ingress of environmental elements proximate the first end of the coupling member; and a compression portion structurally integral with the connector body, wherein the compression portion is configured to break apart from the body when axially compressed.
[0006] A fourth aspect of the present invention relates to a method of fastening a coaxial cable to a communication port, the method comprising: providing a coaxial cable connector including: a connector body; a post operably attached to the connector body; a coupling member axially rotatable with respect to the connector body; an outer sleeve engageable with the coupling member; and a compression portion structurally integral with the connector body; axially compressing the compression portion to form an environmental seal around the coaxial cable, wherein when axially compressed, the compression portion breaks away from the body and securely connects to the coaxial cable; and fastening the coupling member to an interface port by operating the outer sleeve.
[0007] The foregoing and other features of construction and operation of the invention will be more readily understood and fully appreciated from the following detailed disclosure, taken in conjunction with accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:
[0009] FIG. 1A depicts a cross-section view of a first embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0010] FIG. 1B depicts a perspective view of the first embodiment of the coaxial cable connector prior to an embodiment of the sleeve is operably attached to an embodiment of a coupling member;
[0011] FIG. 1C depicts a cross-section view of the first embodiment of the coaxial cable connector after secure attachment to an embodiment of a coaxial cable;
[0012] FIG. 2 depicts a cross-section view of a second embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0013] FIG. 3 depicts a cross-section view of a third embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0014] FIG. 4A depicts a cross-section view of a fourth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0015] FIG. 4B depicts a perspective view of the fourth embodiment of the coaxial cable connector prior to an embodiment of a sleeve is operably attached to an embodiment of a coupling member;
[0016] FIG. 5 depicts a cross-section view of a fifth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0017] FIG. 6 depicts a cross-section view of a sixth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0018] FIG. 7 depicts a cross-section view of an seventh embodiment of a coaxial cable connector including an embodiment of an outer integral sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0019] FIG. 8 depicts a cross-section view of an eighth embodiment of a coaxial cable connector including an embodiment of an outer integral sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0020] FIG. 9 depicts a cross-section view of a ninth embodiment of a coaxial cable connector including an embodiment of an outer integral sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0021] FIG. 10 depicts a cross-section view of a tenth embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0022] FIG. 11 depicts a cross-section view of an eleventh embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0023] FIG. 12 depicts a cross-section view of a twelfth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a sealing member, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0024] FIG. 13 depicts a cross-section view of a thirteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0025] FIG. 14 depicts a cross-section view of a fourteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0026] FIG. 15 depicts a cross-section view of a fifteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0027] FIG. 16 depicts a cross-section view of a sixteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0028] FIG. 17 depicts a cross-section view of a seventeenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0029] FIG. 18 depicts a cross-section view of an eighteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0030] FIG. 19 depicts a cross-section view of a nineteenth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0031] FIG. 20 depicts a cross-section view of a twentieth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0032] FIG. 21 depicts a cross-section view of a twenty-first embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0033] FIG. 22 depicts a cross-section view of a twenty-second embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member; and
[0034] FIG. 23 depicts a cross-section view of a twenty-third embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of an outer sleeve, and an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0035] FIG. 24 depicts a cross-section view of a twenty-fourth embodiment of a coaxial cable connector including an embodiment of an outer sleeve, an embodiment of an outer sleeve, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0036] FIG. 25 depicts a cross-section view of a twenty-fifth embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0037] FIG. 26 depicts a cross-section view of a twenty-sixth embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0038] FIG. 27 depicts a cross-section view of a twenty-seventh embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of a compression portion, and an embodiment of a radial restriction member;
[0039] FIG. 28 depicts a cross-section view of a twenty-eighth embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of an outer sleeve, an embodiment of a compression portion configured to move axially external to an embodiment of a connector body; and
[0040] FIG. 29 depicts a cross-section view of a twenty-ninth embodiment of a coaxial cable connector including an embodiment of a sealing member, an embodiment of an outer sleeve, and an embodiment of a compression portion configured to move axially within an embodiment of a connector body.
DETAILED DESCRIPTION
[0041] Although certain embodiments of the present invention are shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of embodiments of the present invention.
[0042] As a preface to the detailed description, it should be noted that, as used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents, unless the context clearly dictates otherwise.
[0043] Referring to the drawings, FIGS. 1A-29 depict embodiments of a coaxial cable connector 100 - 128 . The coaxial cable connector 100 - 128 may be operably affixed, or otherwise functionally attached, to a coaxial cable 10 having a protective outer jacket 12 , a conductive grounding shield 14 , an interior dielectric 16 and a center conductor 18 (the cable 10 being shown in FIG. 1C ). The coaxial cable 10 may be prepared as embodied in FIG. 1C by removing the protective outer jacket 12 and drawing back the conductive grounding shield 14 to expose a portion of the interior dielectric 16 . Further preparation of the embodied coaxial cable 10 may include stripping the dielectric 16 to expose a portion of the center conductor 18 . The protective outer jacket 12 is intended to protect the various components of the coaxial cable 10 from damage which may result from exposure to dirt or moisture and from corrosion. Moreover, the protective outer jacket 12 may serve in some measure to secure the various components of the coaxial cable 10 in a contained cable design that protects the cable 10 from damage related to movement during cable installation. The conductive grounding shield 14 may be comprised of conductive materials suitable for providing an electrical ground connection, such as cuprous braided material, aluminum foils, thin metallic elements, or other like structures. Various embodiments of the shield 14 may be employed to screen unwanted noise. For instance, the shield 14 may comprise a metal foil wrapped around the dielectric 16 , or several conductive strands formed in a continuous braid around the dielectric 16 . Combinations of foil and/or braided strands may be utilized wherein the conductive shield 14 may comprise a foil layer, then a braided layer, and then a foil layer. Those in the art will appreciate that various layer combinations may be implemented in order for the conductive grounding shield 14 to effectuate an electromagnetic buffer helping to prevent ingress of environmental noise that may disrupt broadband communications. The dielectric 16 may be comprised of materials suitable for electrical insulation, such as plastic foam material, paper materials, rubber-like polymers, or other functional insulating materials. It should be noted that the various materials of which all the various components of the coaxial cable 10 are comprised should have some degree of elasticity allowing the cable 10 to flex or bend in accordance with traditional broadband communication standards, installation methods and/or equipment. It should further be recognized that the radial thickness of the coaxial cable 10 , protective outer jacket 12 , conductive grounding shield 14 , interior dielectric 16 and/or center conductor 18 may vary based upon generally recognized parameters corresponding to broadband communication standards and/or equipment.
[0044] Referring further to FIGS. 1A-29 , a connector, such as connector 100 - 128 may also interact with a coaxial cable interface port 20 . The coaxial cable interface port 20 includes a conductive receptacle for receiving a portion of a coaxial cable center conductor 18 sufficient to make adequate electrical contact. The coaxial cable interface port 20 may further comprise a threaded exterior surface 23 . It should be recognized that the radial thickness and/or the length of the coaxial cable interface port 20 and/or the conductive receptacle of the port 20 may vary based upon generally recognized parameters corresponding to broadband communication standards and/or equipment. Moreover, the pitch and height of threads which may be formed upon the threaded exterior surface 23 of the coaxial cable interface port 20 may also vary based upon generally recognized parameters corresponding to broadband communication standards and/or equipment. Furthermore, it should be noted that the interface port 20 may be formed of a single conductive material, multiple conductive materials, or may be configured with both conductive and non-conductive materials corresponding to the port's 20 operable electrical interface with a connector 100 - 128 . However, the receptacle of the port 20 should be formed of a conductive material, such as a metal, like brass, copper, or aluminum. Further still, it will be understood by those of ordinary skill that the interface port 20 may be embodied by a connective interface component of a coaxial cable communications device, a television, a modem, a computer port, a network receiver, or other communications modifying devices such as a signal splitter, a cable line extender, a cable network module and/or the like.
[0045] Referring now to FIGS. 1A-25 , embodiments of a coaxial cable connector 100 - 123 may further comprise a coupling member 30 , a post 40 , a connector body 50 , an outer sleeve 90 , a compression portion 60 , a radial restriction member 65 , and a connector body seal member 5 (as shown in FIG. 28 ), such as, for example, a body O-ring configured to fit around a portion of the connector body 50 . Embodiments of coupling member 30 may be coupling member 30 a , 30 b , or 30 c described in further detail infra. Embodiments of sleeve 90 may be sleeve 90 a , 90 b , 90 c , 90 d , 90 e , 90 f , 90 g , or 90 h , described in further detail infra. Similarly, embodiments of radial restriction member 65 may be 65 a , 65 b , or 65 c , described in further detail infra. Connector 100 - 123 may come in a preassembled configuration or may require additional operable attachment of the sleeve 90 to connector 100 - 123 during installation.
[0046] Referring now to FIG. 1A , embodiments of connector 100 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 a , a compression portion 60 , and a radial restriction member 65 a.
[0047] Embodiments of connector 100 may include a coupling member 30 a . The coupling member 30 a of embodiments of a coaxial cable connector 100 has a first forward end 31 a and opposing second rearward end 32 a . The coupling member 30 a may comprise internal threading 33 a extending axially from the edge of first forward end 31 a a distance sufficient to provide operably effective threadable contact with the external threads 23 of a standard coaxial cable interface port 20 (as shown, by way of example, in FIG. 1C ). The coupling member 30 a includes an internal lip 34 a , such as an annular protrusion, located proximate the second rearward end 32 a of the coupling member. The internal lip 34 a includes a surface 35 a facing the first forward end 31 a of the coupling member 30 a . The forward facing surface 35 a of the lip 34 a may be a tapered surface or side facing the first forward end 31 a of the coupling member 30 a . However, the internal lip 34 a of coupling member 30 a may define the second end 32 a of the coupling member 30 a , eliminating excess material from the coupling member 30 a . Located somewhere on the outer surface 36 a of the coupling member 30 a may be a retaining structure 37 a . The retaining structure 37 a of the coupling member 30 a may be an annular groove or recess that extends completely or partially around the outer surface 36 a of the coupling member 30 a to retain, accommodate, receive, or mate with an engagement member 97 of the sleeve 90 . Alternatively, the retaining structure 37 a may be an annular protrusion that extends completely or partially around the outer surface 36 a of the coupling member 30 a to retain or mate with the engagement member 97 of the outer sleeve 90 . The retaining structure 37 a may be placed at various axial positions from the first end 31 a to the 32 a , depending on the configuration of the sleeve 90 and other design requirements of connector 100 .
[0048] Moreover, embodiments of coupling member 30 a may include an outer surface feature(s) 38 a proximate or otherwise near the second end 32 a to improve mechanical interference or friction between the coupling member 30 a and the sleeve 90 . For instance, the outer surface feature 38 a may extend completely or partially around the outer surface 36 a proximate the second 32 a of the coupling member 30 a to increase a retention force between an inner surface 93 of the sleeve 90 and the outer surface 36 a of the coupling member 30 a . The outer surface feature 38 a may include a knurled surface, a slotted surface, a plurality of bumps, ridges, grooves, or any surface feature that may facilitate contact between the sleeve 90 and the coupling member 30 a . In one embodiment, the coupling member 30 a may be referred to as a press-fit coupling member.
[0049] The structural configuration of the coupling member 30 a may vary according differing connector design parameters to accommodate different functionality of a coaxial cable connector 100 . For instance, the first forward end 31 a of the coupling member 30 a may include internal and/or external structures such as ridges, grooves, curves, detents, slots, openings, chamfers, or other structural features, etc., which may facilitate the operable joining of an environmental sealing member, such a water-tight seal or other attachable component element, that may help prevent ingress of environmental contaminants, such as moisture, oils, and dirt, at the first forward end 31 a of the coupling member 30 a , when mated with an interface port 20 . Those in the art should appreciate that the coupling member 30 a need not be threaded. Moreover, the coupling member 30 a may comprise a coupler commonly used in connecting RCA-type, or BNC-type connectors, or other common coaxial cable connectors having standard coupler interfaces. The coupling member 30 a may be formed of conductive materials, such as copper, brass, aluminum, or other metals or metal alloys, facilitating grounding through the coupling member 30 a . Further embodiments of the coupling member 30 a may be formed of polymeric materials and may be non-conductive. Accordingly, the coupling member 30 a may be configured to extend an electromagnetic buffer by electrically contacting conductive surfaces of an interface port 20 when a connector 100 is advanced onto the port 20 . In addition, the coupling member 30 a may be formed of both conductive and non-conductive materials. For example the external surface of the coupling member 30 a may be formed of a polymer, while the remainder of the coupling member 30 a may be comprised of a metal or other conductive material. The coupling member 30 a may be formed of metals or polymers or other materials that would facilitate a rigidly formed coupling member body. Manufacture of the coupling member 30 a may include casting, extruding, cutting, knurling, turning, tapping, drilling, injection molding, blow molding, combinations thereof, or other fabrication methods that may provide efficient production of the component. The forward facing surface 35 a of the coupling member 30 a faces a flange 44 the post 40 when operably assembled in a connector 100 , so as to allow the coupling member 30 a to rotate with respect to the other component elements, such as the post 40 and the connector body 50 , of the connector 100 .
[0050] Embodiments of connector 100 may include a post 40 . The post 40 comprises a first forward end 41 and an opposing second rearward end 42 . Furthermore, the post 40 may comprise a flange 44 , such as an externally extending annular protrusion, located at the first end 41 of the post 40 . The flange 44 includes a rearward facing surface 45 that faces the forward facing surface 35 a , 35 b , 35 c of the coupling member 30 a , 30 b , 30 c when operably assembled in a coaxial cable connector, so as to allow the coupling member 30 to rotate with respect to the other component elements, such as the post 40 and the connector body 50 , of the connector 100 - 128 . The rearward facing surface 45 of flange 44 may be a tapered surface facing the second rearward end 42 of the post 40 . Further still, an embodiment of the post 40 may include a surface feature 47 such as a lip or protrusion that may engage a portion of a connector body 50 to secure axial movement of the post 40 relative to the connector body 50 . However, the post need not include such a surface feature 47 , and the coaxial cable connector 100 - 128 may rely on press-fitting and friction-fitting forces and/or other component structures having features and geometries to help retain the post 40 in secure location both axially and rotationally relative to the connector body 50 . The location proximate or near where the connector body is secured relative to the post 40 may include surface features 43 , such as ridges, grooves, protrusions, or knurling, which may enhance the secure attachment and locating of the post 40 with respect to the connector body 50 . Moreover, various components having larger or smaller diameters can be readily press-fit or otherwise secured into connection with each other. Additionally, the post 40 may include a mating edge 46 , which may be configured to make physical and electrical contact with a corresponding mating edge 26 of an interface port 20 (as shown in exemplary fashion in FIG. 1C ) The post 40 should be formed such that portions of a prepared coaxial cable 10 including the dielectric 16 and center conductor 18 (examples shown in FIG. 1C ) may pass axially into the second end 42 and/or through a portion of the tube-like body of the post 40 . Moreover, the post 40 should be dimensioned, or otherwise sized, such that the post 40 may be inserted into an end of the prepared coaxial cable 10 , around the dielectric 16 and under the protective outer jacket 12 and conductive grounding shield 14 . Accordingly, where an embodiment of the post 40 may be inserted into an end of the prepared coaxial cable 10 under the drawn back conductive grounding shield 14 , substantial physical and/or electrical contact with the shield 14 may be accomplished thereby facilitating grounding through the post 40 . The post 40 should be conductive and may be formed of metals or may be formed of other conductive materials that would facilitate a rigidly formed post body. In addition, the post may be formed of a combination of both conductive and non-conductive materials. For example, a metal coating or layer may be applied to a polymer of other non-conductive material. Manufacture of the post 40 may include casting, extruding, cutting, turning, drilling, knurling, injection molding, spraying, blow molding, component overmolding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0051] Embodiments of a coaxial cable connector, such as connector 100 , may include a connector body 50 . The connector body 50 may comprise a first end 51 and opposing second end 52 . Moreover, the connector body may include a post mounting portion 57 proximate or otherwise near the first end 51 of the body 50 , the post mounting portion 57 configured to securely locate the body 50 relative to a portion of the outer surface of post 40 , so that the connector body 50 is axially secured with respect to the post 40 , in a manner that prevents the two components from moving with respect to each other in a direction parallel to the axis of the connector 100 . The internal surface of the post mounting portion 57 may include an engagement feature, such as an annular detent or ridge having a different diameter than the rest of the post mounting portion 57 . However other features such as grooves, ridges, protrusions, slots, holes, keyways, bumps, nubs, dimples, crests, rims, or other like structural features may be included. In addition, the connector body 50 may include an outer annular recess 58 located proximate or near the first end 51 of the connector body 50 . Furthermore, the connector body 50 may include a semi-rigid, yet compliant outer surface 55 , wherein the outer surface 55 may be configured to form an annular seal when the second end 52 is deformably compressed against a received coaxial cable 10 by operation of a compression portion 60 . The connector body 50 may include an outer ramped surface 56 and an internal annular notch 59 or groove proximate the second end 52 to structurally facilitate the deformation of the connector body 50 , as described in further detail infra.
[0052] Moreover, the connector body 50 may include an external annular detent located proximate or close to the second end 52 of the connector body 50 . Further still, the connector body 50 may include internal surface features, such as annular serrations formed near or proximate the internal surface of the second end 52 of the connector body 50 and configured to enhance frictional restraint and gripping of an inserted and received coaxial cable 10 , through tooth-like interaction with the cable. The connector body 50 may be formed of materials such as plastics, polymers, bendable metals or composite materials that facilitate a semi-rigid, yet compliant outer surface 55 . Further, the connector body 50 may be formed of conductive or non-conductive materials or a combination thereof. Manufacture of the connector body 50 may include casting, extruding, cutting, turning, drilling, knurling, injection molding, spraying, blow molding, component overmolding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0053] With continued reference to FIG. 1A , embodiments of connector 100 may include a sleeve 90 a . The sleeve 90 a may be engageable with the coupling member 30 a . The sleeve 90 a may include a first end 91 a , a second 91 a , an inner surface 93 a , and an outer surface 94 a . The sleeve 90 a may be a generally annular member having a generally axial opening therethrough. The sleeve 90 a may be radially disposed over the coupling member 30 a , or a portion thereof, the connector body 50 , or a portion thereof the compression portion 60 , or a portion thereof, and radial restriction member 65 , or a portion thereof, while operably assembled and/or in a compressed position. Proximate or otherwise near the first end 91 a , the sleeve 90 a may include an engagement member 97 a configured to mate or engage with the retaining structure 37 a of the coupling member 30 a . The engagement member 97 a may be an annular lip or protrusion that may enter or reside within the retaining structure 37 a of the coupling member 30 a . For example, in embodiments where the retaining structure 37 a is an annular groove, the engagement member 97 a may be a protrusion or lip that may snap into the groove located on the coupling member 30 a to retain the sleeve 90 a in a single axial position. In other words, the cooperating surfaces of the groove-like retaining structure 37 a and the lip or protruding engagement member 97 a may prevent axial movement of the sleeve 90 a once the connector 100 is in an assembled configuration. Alternatively, the engagement member 97 a may be an annular groove or recess that may receive or engage with the retaining structure 37 a of the coupling member 30 a . For example, in embodiments where the retaining structure 37 a of the coupling member 30 a is an annular protrusion, the engagement member 97 a may be a groove or recess that may allow the annular protruding retaining structure 37 a of the coupling member 30 a to snap into to retain the sleeve 90 a in a single axial position. In other words, the cooperating surfaces of the protruding retaining structure 37 a and the groove-like engagement member 97 a may prevent axial movement of the sleeve 90 a once the connector 100 is in an assembled configuration. Those having skill in the art should understand that various surface features effectuating cooperating surfaces between the coupling member 30 and the sleeve 90 may be implemented to retain the sleeve 90 a with respect to the rest of the connector 100 in an axial direction. Furthermore, the engagement member 97 a of the sleeve 90 a may be segmented such that one or more gaps may separate portions of the engagement member 97 a , while still providing sufficient structural engagement with the retaining structure 37 a.
[0054] An embodiment of an assembled configuration of connector 100 with respect to the sleeve 90 a may involve sliding the sleeve 90 a over the coupling member 30 a in an axial direction starting from the first end 31 a and continuing toward the second end 32 a of the coupling member 30 a until sufficient mating and/or engagement occurs between the engagement member 97 a of the sleeve 90 a and the retaining structure 37 a of the coupling member 30 a , as shown in FIG. 1B . Once in the assembled configuration, rotation of the sleeve 90 a may in turn cause the coupling member 30 a to simultaneously rotate in the same direction as the sleeve 90 a due to mechanical interference between the inner surface 93 a of the sleeve 90 a and the outer surface 36 a of the coupling member 30 a . In some embodiments, the interference between the sleeve 90 a and the coupling member 30 a relies simply on a friction fit or interference fit between the components. Other embodiments include a coupling member 30 a with an outer surface feature(s) 38 a , as described supra, to improve the mechanical interference between the components. Further embodiments include a sleeve 90 a with internal surface features 98 a positioned on the inner surface 93 a to improve the contact between the components. Even further embodiments of connector 100 may include a sleeve 90 a and a coupling member 30 a both having surface features 98 a , 38 a , respectively. Embodiments of the inner surface features 98 a of the sleeve 90 a may include a knurled surface, a slotted surface, a plurality of bumps, ridges, rib, grooves, or any surface feature that may facilitate contact between the sleeve 90 a and the coupling member 30 . In many embodiments, the inner surface features 98 a of the sleeve 90 a and the outer surface features 38 a of the coupling member 30 a may structurally correspond with each other. For example, the inner geometry of the sleeve 90 a may reflect and/or structurally correspond with the outer geometric shape of the coupling member 30 a . Due to the engagement between the sleeve 90 a and the coupling member 30 a , a user may simply grip and rotate/twist the sleeve 90 a to thread the coupling element 30 a onto an interface port, such as interface port 20 . Further still, embodiments of the sleeve 90 a may include outer surface features 99 a , such as annular serrations or slots, configured to enhance gripping of the sleeve 90 a while connecting the connector 100 onto an interface port. The sleeve 90 a may be formed of materials such as plastics, polymers, bendable metals or composite materials that facilitate a rigid body. Further, the sleeve 90 a may be formed of conductive or non-conductive materials or a combination thereof. Manufacture of the sleeve 90 a may include casting, extruding, cutting, turning, drilling, knurling, injection molding, spraying, blow molding, component overmolding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0055] Embodiments of connector 100 may include a compression portion 60 . Compression portion 60 may be operably attached to the connector body 50 . For instance, the compression portion 60 may be structurally integral with the connector body 50 , wherein the compression portion 60 separates or shears from the connector body 50 upon an axial force which in turn radially compresses the second end 52 of the connector body 50 onto the coaxial cable 10 , as shown in FIG. 1C . The structural connection between the connector body 50 and the compression portion 60 may be thin or otherwise breakable when compressive, axial force is applied (e.g. by an axial compression tool). For example, the compression portion 60 may have a frangible connection with the connector body 50 . Moreover, the structural connection or configuration between the connector body 50 and the compression portion 60 may be defined by an internal annular notch 66 or groove of the compression portion 60 and an outer ramped surface 56 of the connector body 50 . The annular notch 59 of the connector body 50 may further facilitate the deformation of the second end 52 of the connector body 1350 . The compression portion 60 may be formed of the same material as connector body 50 because they may be structurally integral with each other. For example, the compression portion 60 may be comprised of materials such as plastics, polymers, bendable metals or composite materials that facilitate a rigid body. Further, the compression portion 60 may be formed of conductive or non-conductive materials or a combination thereof. Manufacture of the compression member 60 may include casting, extruding, cutting, turning, drilling, knurling, injection molding, spraying, blow molding, component overmolding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0056] Furthermore, embodiments of connector 100 may include a radial restriction member 65 a . The radial restriction member 65 a may be a bushing or similar annular tubular member disposed proximate the rearward second end 52 of the connector body 50 . For instance, the radial restriction member 65 a may surround the compression portion 60 and a portion of the connector body 50 proximate the rearward second end 52 . The radial restriction member 65 a may be a generally annular, hollow cylindrically-shaped sleeve-like member comprised of stainless steel or other substantially rigid materials which may structurally assist the crack and seal process of compression portion 60 . For instance, when the compression portion 60 is axially compressed in a direction towards the coupling member 30 , the radial restriction member 65 a may axially displace along with the compression portion 60 and may prevent the compression portion 60 from splintering or otherwise displacing in a direction other than substantially axial towards the coupling member 30 .
[0057] Embodiments of the compression portion 60 may create an environmental seal around the coaxial cable 10 when in the fully compressed position. Specifically, when the compression portion 60 (and the radial restriction member 65 a ) is axially slid or compressed towards the coupling member 30 , the structural connection between the compression portion 60 and the connector body 50 is severed, sheared, ruptured, etc., and the compression portion 60 comes into contact with the outer ramped surface 56 of the connector body 50 . The severing of the structural connection between the connector body 50 and the compression portion 60 essentially turns the internal notch 66 a into a cooperative ramped surface with the outer ramped surface 56 of the connector body 50 . Due to the cooperative ramped surfaces, the axial compression (displacement) of the compression portion 60 evenly compresses the second end 52 of the connector body 50 onto the outer jacket 12 of the coaxial cable 10 and deforms the outer ramped surface 56 , as shown in FIG. 1C . Accordingly, the compression portion 60 and potentially the radial restriction member 65 a may be referred to as a crack and seal compression means with a radial restriction member 65 a . Those skilled in the requisite art should appreciate that the seal may be created by the compression portion 60 without the radial restriction member 65 a . However, the radial restriction member 65 a significantly enhances the structural integrity and functional operability of the compression portion, for example, when it is compressed and sealed against an attached coaxial cable 10 .
[0058] With reference to FIG. 2 , embodiments of connector 101 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 a , a compression portion 60 , and a radial restriction member 65 c . Radial restriction member 65 c may share the same or substantially the same function as radial restriction member 65 a . However, radial restriction member 65 c may be a cap member, or similar generally annular, tubular member having an engagement surface for operable engagement with a compression tool. For instance, embodiments of the radial restriction member 65 c may include an internal annular lip 63 or inwardly extending flange proximate a rearward end 62 of the radial restriction member 65 c . The radial restriction member 65 c may surround or partially surround the compression portion 60 and a portion of the connector body 50 proximate the rearward second end 52 , wherein the internal annular lip 63 of the radial restriction member 65 c may be configured to contact the compression portion 6 a prior to or upon axial compression of the connector. The radial restriction member 65 c may be comprised of stainless steel or other substantially rigid materials which may structurally assist the crack and seal process of compression portion 60 . For instance, when the compression portion 60 is axially compressed in a direction towards the coupling member 30 , the radial restriction member 65 c may axially displace along with the compression portion 60 and may prevent the compression portion 60 from splintering or otherwise displacing in a direction other than substantially axial towards the coupling member 30 . Additionally, the internal lip 63 proximate the rearward end 62 of the radial restriction member 65 c may provide an engagement surface for operable engagement with a compression tool, or other device/means that provides the necessary compression to compress seal connector 1302 .
[0059] Referring now to FIG. 3 , embodiments of connector 102 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 a , a compression portion 60 , and a radial restriction member 65 b . Radial restriction member 65 b may share the same or substantially the same function as radial restriction member 65 a . However, radial restriction member 65 b may be one or more straps or bands that extend annularly around or partially around the compression portion 60 . The radial restriction member 65 b may be structurally attached to the compression portion 60 in a variety of methods, such as press-fit, adhesion, cohesion, fastened, etc. For instance, the radial restriction member 65 b may reside within annular notches or grooves in the compression portion 60 . The notches or grooves may have various depths to allow the radial restriction member 65 to be flush with the outer surface of the compression portion 60 , to protrude from the outer surface of the compression portion 60 , or to reside completely beneath the outer surface of the compression portion 60 . Moreover, the radial restriction member 65 may be comprised of stainless steel or other substantially rigid materials which may structurally assist the crack and seal process of compression portion 60 . For instance, when the compression portion 60 is axially compressed in a direction towards the coupling member 30 a , the radial restriction member 65 b may also prevent the compression portion 60 from splintering or otherwise displacing in a direction other than substantially axial towards the coupling member 30 a.
[0060] With reference to FIG. 4A , embodiments of connector 103 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 b , a compression portion 60 , and a radial restriction member 65 a.
[0061] Embodiments of a connector 103 may include a coupling member 30 b . Coupling member 30 b may share the same or substantially the same structural and functional aspects of coupling member 30 a . Accordingly, coupling member 30 b has a first forward end 31 b , an opposing second rearward end 32 b , internal threading 33 b , an internal lip 34 b including a surface 35 b facing the first forward end 31 b of the coupling member 30 b . However, the second rearward end 32 b , of the coupling member 30 b may extend a significant axial distance to reside radially extent, or otherwise partially surround, a portion of the connector body 50 , although the extended portion of the coupling member 30 b need not contact the connector body 50 . Additionally, coupling member 30 b may include a retaining structure 37 b on an outer surface 36 b of the coupling member 30 b . The retaining structure 37 b may share the same or substantially same structural and functional aspects of the retaining structure 37 a described in association with, for example, connector 100 . Manufacture of the coupling member 30 b may include casting, extruding, cutting, knurling, turning, tapping, drilling, injection molding, blow molding, combinations thereof, or other fabrication methods that may provide efficient production of the component. The forward facing surface 35 b of the coupling member 30 b faces a flange 44 the post 40 when operably assembled in a coaxial cable connector, so as to allow the coupling member 30 b to rotate with respect to the other component elements, such as the post 40 and the connector body 50 .
[0062] Embodiments of connector 103 may include an outer sleeve 90 b . Sleeve 90 b may share the same structural and functional aspects of sleeve 90 a described in association with, for example, connector 100 . Accordingly, sleeve 90 b may include an engagement member 97 b that is configured to mate or engage with a retaining structure 37 b of the coupling member 30 b . For example, the sleeve 90 b may include a first end 91 b , a second end 92 b , an inner surface 93 b , and an outer surface 94 b , and may be a generally annular member having a generally axial opening therethrough. However, the sleeve 90 b may be radially disposed over the coupling member 30 b , or a portion thereof, the connector body 50 , or a portion thereof, the compression portion 60 , or a portion thereof, and the radial restriction member 65 , while operably assembled and/or in a compressed position. Additionally, the sleeve 90 b may include an annular ramped surface 95 b or chamfer proximate or otherwise near the first end 91 b to accommodate an increased diameter or general size of the coupling member 30 b proximate a second, rearward end 32 b of the coupling member 30 b . Embodiments of the ramped surface 95 b may be structurally integral with the engagement member 97 b and the body of the sleeve 90 b . Furthermore, embodiments of an assembled configuration of connector 103 with respect to the sleeve 90 b may involve sliding the sleeve 90 b over the coupling member 30 b in an axial direction starting from the first end 31 b and continuing toward the second end 32 b of the coupling member 30 b until sufficient mating and/or engagement occurs between the engagement member 97 b of the sleeve 90 b and the retaining structure 37 b of the coupling member 30 b , as shown in FIG. 4B . Sleeve 90 b may also include outer surface feature(s) 99 b , such as annular serrations or slots, configured to enhance gripping of the sleeve 90 while connecting the coaxial cable connector onto an interface port.
[0063] FIG. 5 depicts an embodiment of connector 104 . Embodiments of connector 104 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 b , a compression portion 60 , and a radial restriction member 65 c.
[0064] FIG. 6 depicts an embodiment of connector 105 . Embodiments of connector 105 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 b , a compression portion 60 , and a radial restriction member 65 b
[0065] Referring now to FIG. 7 , embodiments of connector 106 may include an integral sleeve 90 c , a post 40 , a connector body 50 , a compression portion 60 , and a radial restriction member 65 a.
[0066] Embodiments of connector 106 may include an integral sleeve 90 c . An integral sleeve 90 c may be a generally annular member having a generally axial opening therethrough. The integral sleeve 90 c may include a first end 91 c , a second end 1392 c , an outer surface 93 c , and an outer surface 94 c . Furthermore, the integral sleeve 90 c may include a coupling portion 95 c proximate the first end 91 c and a body portion 96 c structurally integral with the coupling portion 95 c . The coupling portion 95 c may include internal threads for operable engagement with an interface port, such as interface port 20 . For instance, the internal threads of the coupling portion 95 c of the integral sleeve 90 c may correspond to threads on the outer surface of an interface port. The coupling portion 95 c may also include an internal lip 97 c , such as an annular protrusion. The internal lip 97 c includes a surface 98 c facing the first forward end 91 c of the integral sleeve 90 c . The forward facing surface 98 c of the lip 97 c may be a tapered surface that corresponds to a tapered surface 45 of the post 40 . The forward facing surface 98 c of the coupling portion 95 c faces the flange 44 of the post 40 when operably assembled in a connector 106 , so as to allow the integral sleeve 90 c to rotate with respect to the other component elements, such as the post 40 and the connector body 50 . The structural configuration of the coupling portion 95 c of integral sleeve 90 c may vary according to differing connector design parameters to accommodate different functionality of a coaxial cable connector. For instance, the first forward end 91 c of the integral sleeve 90 c may include internal and/or external structures such as ridges, grooves, curves, detents, slots, openings, chamfers, or other structural features, etc., which may facilitate the operable joining of an environmental sealing member, such a water-tight seal or other attachable component element, that may help prevent ingress of environmental contaminants, such as moisture, oils, and dirt, at the first forward end 91 c of the integral sleeve 90 c , when mated with an interface port 20 . Those in the art should appreciate that the coupling portion 95 c need not be threaded.
[0067] Moreover, the integral sleeve 90 c includes a body portion 96 c that may be structurally integral with the coupling portion 95 c to form an outer sleeve that may surround the post 40 , the connector body 50 , the compression portion 60 , or a portion thereof, and the radial restriction member 65 , or a portion thereof when in an assembled and/or compressed position. Because the body portion 96 c may be structurally integral with the coupling portion 95 c , rotation or twisting of the body portion 96 c can cause rotation or twisting of the coupling portion 95 c to operably mate a coaxial cable connector, such as connector 106 , onto an interface port. Thus, the integral sleeve 90 c includes a larger surface area to grip and twist the integral sleeve 90 c to thread the coupling portion 95 c fully onto the interface port, such as interface port 20 . Embodiments of the body portion 96 c of the integral sleeve 90 c may include outer surface features, such as annular serrations or slots, configured to enhance gripping of the integral sleeve 90 c while connecting the coaxial cable connector onto an interface port. The body portion 96 c of the sleeve 90 c may be formed of materials such as plastics, polymers, bendable metals or composite materials that facilitate a rigid body, while the coupling portion 95 c may be formed of conductive materials, such as copper, brass, aluminum, or other metals or metal alloys, facilitating grounding through the connector. In other words, the integral sleeve 90 c may be formed of both conductive and non-conductive materials. For example, the external surface of the coupling portion 95 c of the integral sleeve 90 c may be formed of a polymer, while the remainder of the coupling portion 95 c may be comprised of a metal or other conductive material. Alternatively, the coupling portion 95 c and the body portion 96 c of the integral sleeve 90 c may be formed of conductive materials such as metals or metal alloys, or may both be formed of polymers or other materials that would facilitate a rigidly formed component. Manufacture of the integral sleeve 90 c may include casting, extruding, cutting, knurling, turning, tapping, drilling, injection molding, blow molding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0068] FIG. 8 depicts an embodiment of connector 107 . Embodiments of connector 107 may include an integral sleeve 90 c , a post 40 , a connector body 50 , a compression portion 60 , and a radial restriction member 65 c.
[0069] FIG. 9 depicts an embodiment of connector 108 . Embodiments of connector 108 may include an integral sleeve 90 c , a post 40 , a connector body 50 , a compression portion 60 , and a radial restriction member 65 b.
[0070] With reference now to FIG. 10 , embodiments of connector 109 may include a coupling member 30 c , a post 40 , a connector body 50 , a sleeve 90 h , a sealing member 80 , a compression portion 60 , and a radial restriction member 65 a.
[0071] Embodiments of connector 109 may include a coupling member 30 c . Coupling member 30 c may share some of the structural and functional aspects of embodiments of coupling member 30 a , 30 b , such as being mated, threaded or otherwise, to a corresponding interface port 20 . Coupling member 30 c may include a first end 31 c , a second end 32 c , an inner surface 33 c , at least a portion of which is threaded, a connector-grasping portion 39 c , and an outer surface 34 c , including a seal-grasping surface portion 36 c . The seal-grasping surface portion 36 c may be a flat, smooth surface or a flat, roughened surface suitable to frictionally and/or adhesively engage an interior sealing surface 83 of the sealing member 80 . Embodiments of the seal-grasping surface portion 36 c may also contain a ridge that together with the seal grasping surface portion 36 c forms a groove or shoulder that is suitably sized and shaped to correspondingly engage an internal shoulder 87 of the sealing member 80 adjacent the interior sealing surface 83 in a locking-type interference fit between the coupling member 30 c and the sealing member 80 .
[0072] Moreover, the coupling member 30 c may further include a coupling member-turning surface portion on an outer surface 84 of the sealing member 80 . The coupling member-turning surface portion may have at least two flat surface regions that allow engagement with the surfaces of a tool such as a wrench. In one embodiment, the coupling member-turning surface is hexagonal. Alternatively, the coupling member-turning surface may be a knurled surface to facilitate hand-turning of the nut component. Furthermore, upon engagement of the sealing member 80 with the coupling member 30 c , a rear sealing surface of the sealing member 80 abuts a side/edge surface of the coupling member 30 c to form a sealing relationship in that region. In one embodiment, the connector-grasping portion 36 c of the coupling member 30 c is an internally-projecting shoulder that engages a flange 44 of the post 40 in such a manner that the coupling member 30 c can be freely rotated as it is held in place as part of the connector.
[0073] With continued reference to FIG. 10 , connector 109 may include a sealing member 80 . The sealing member may include a first end 81 , a second end 82 , an inner surface 83 , and an outer surface 84 . The sealing member 80 may have a generally tubular body that is elastically deformable by nature of its material characteristics and design. In most embodiments, the seal member 80 is a one-piece element made of a compression molded, elastomer material having suitable chemical resistance and material stability (i.e., elasticity) over a temperature range between about −40° C. to +40° C. For example, the sealing member 80 may be made of silicone rubber. Alternatively, the material may be propylene, a typical O-ring material. Other materials known in the art may also be suitable. Furthermore, the first end 81 of sealing member 80 may be a free end for ultimate engagement with a port, while the second end 82 may be for ultimate connection to the coupling member 30 c . The sealing member 80 may have a forward sealing surface, a rear sealing portion including an interior sealing surface 83 that integrally engages the coupling member 30 c , and an integral joint-section intermediate the first and second end 81 , 82 of the tubular body of the sealing member 80 . The forward sealing surface 85 at the first end 81 of the sealing member 80 may include annular facets to assist in forming a seal with the port, such as interface port 20 . Alternatively, forward sealing surface 85 may be a continuous rounded annular surface that forms effective seals through the elastic deformation of the inner surface 83 and end of the sealing member 80 compressed against the port. The integral joint-section includes a portion of the length of the sealing member 80 which is relatively thinner in radial cross-section to encourage an outward expansion or bowing of the seal upon its axial compression. In an exemplary embodiment, the coupling member grasping surface includes an interior sealing surface which forms an annular surface on the inside of the tubular body, and an internal shoulder 87 of the tubular body adjacent the second end 82 . Accordingly, compressive axial force may be applied against one or both ends of the seal depending upon the length of the port intended to be sealed. The force will act to axially compress the seal whereupon it will expand radially in the vicinity of the integral joint-section. In one embodiment, the integral joint-section is located axially asymmetrically intermediate the first end 81 and the second end 82 of the tubular body, and adjacent an anterior end of the interior sealing surface 83 . Embodiments of the sealing member 80 may have an interior diameter at the integral joint-section equal to about 0.44 inches in an uncompressed state; the tubular body of the sealing member 80 may have a length from the first end 81 to the second end 82 of about 0.36 inches in an uncompressed state. However, it is contemplated that the joint-section can be designed to be inserted anywhere between she sealing surface and the first end 81 . The sealing member 80 may prevent the ingress of corrosive elements when the seal is used for its intended function.
[0074] Referring still to FIG. 10 , embodiments of connector 109 may include an outer sleeve 90 h . The outer sleeve 90 h may be engageable with coupling member 30 c . Sleeve 90 h may share the same or substantially the same structural and functional aspects of sleeve 90 a , described supra, and sleeve 90 d , 90 f , described infra. Accordingly, the sleeve 90 h may include a first end 91 h , a second end 92 h , an inner surface 93 h , and an outer surface 94 h . However, the sleeve 90 h need not include an engagement member, such as an embodiment of engagement member 97 a . The mechanical interference to effectuate simultaneous rotation/twisting of the sleeve 90 h and the coupling member 30 c between coupling member 30 c and sleeve 90 h may rely on a press-fit or interference fit between the components. Alternatively, the sleeve 90 h may and coupling member 30 c may include corresponding internal (sleeve 90 h ) and external (coupling member 30 c ) surface features to facilitate mechanical interference between the components. Internal and external surface features of sleeve 90 h and coupling member 30 c may share the structural and functional aspects as surface features 98 a and 38 a , as described in association with, for example, connector 100 .
[0075] FIG. 11 depicts an embodiment of connector 110 . Embodiments of connector 110 may include a coupling member 30 c , a post 40 , a connector body 50 , a sleeve 90 h , a sealing member 80 , a compression portion 60 , and a radial restriction member 65 c.
[0076] FIG. 12 depicts an embodiment of connector 111 . Embodiments of connector 111 may include a coupling member 30 c , a post 40 , a connector body 50 , a sleeve 90 h , a sealing member 80 , a compression portion 60 , and a radial restriction member 65 b.
[0077] With continued reference to the drawings, FIG. 13 depicts an embodiment of connector 112 . Embodiments of connector 112 may include a coupling member 30 a , a post 40 , a connector body 50 , a sleeve 90 d , a compression portion 60 , and a radial restriction member 65 a.
[0078] Embodiments of connector 112 may include a sleeve 90 d . Sleeve 90 d may be engageable with the coupling member 30 a . Sleeve 90 d may share the same or substantially the same structural and functional aspects of sleeve 90 a . Accordingly, sleeve 90 d may include an engagement member 97 d that is configured to mate or engage with a retaining structure 37 a of the coupling member 30 a . Additionally, the sleeve 90 d may include a first end 91 d , a second end 92 d , an inner surface 93 d , and an outer surface 94 d , and may be a generally annular member having a generally axial opening therethrough. Additionally, sleeve 90 d may surround the coupling member 30 a , the post 40 , the connector body 50 , or a portion thereof, the compression portion 60 , and a radial restriction member 65 , or a portion thereof when in an assembled and/or compressed position. However, the sleeve 90 d may extend towards the first end 31 a of coupling member 30 a . In one embodiment, the first end 91 d of the sleeve 90 d may be flush or substantially flush with an edge of the coupling member 30 a proximate or otherwise near the first end 31 a of the coupling member 30 a . Moreover, the engagement member 97 d may be located proximate or otherwise near the edge of the first end 91 d of the sleeve 90 d . The engagement member 97 d may be configured to mate or engage a retaining structure 37 a of the coupling member 30 a that is correspondingly located proximate or otherwise near the first end 31 a of the coupling member 30 a.
[0079] FIG. 14 depicts an embodiment of connector 113 . Embodiments of connector 113 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 d , a compression portion 60 , and a radial restriction member 65 c.
[0080] FIG. 15 depicts an embodiment of connector 114 . Embodiments of connector 114 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 d , a compression portion 60 , and a radial restriction member 65 b.
[0081] Referring now to FIG. 16 , embodiments of connector 115 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 g , a compression portion 60 , and a radial restriction member 65 a.
[0082] Embodiments of connector 115 may include an outer sleeve 90 g . Sleeve 90 g may be engageable with the coupling member 30 b . Sleeve 90 g may share the same or substantially the same function as sleeve 90 b and sleeve 90 f described infra. Accordingly, the sleeve 90 g may include a first end 91 g , a second end 92 g , an inner surface 93 g , and an outer surface 94 g , and may be a generally annular member having a generally axial opening therethrough. Sleeve 90 g may surround the coupling member 30 b , the post 40 , the connector body 50 , or a portion thereof, the compression portion 60 , and a radial restriction member 65 , or a portion thereof, when in an assembled and/or compressed position. Moreover, the sleeve 90 g may extend towards the first end 31 b of coupling member 30 b . However, sleeve 90 g may include an inwardly extending lip 97 g proximate or otherwise near the first end 91 g of the sleeve 90 g , which can help guide the coupling member 30 b onto a corresponding interface port. The lip 97 g may share the same structural and functional aspects of the engagement member 97 b . For instance, the lip 97 g may radially inwardly extend a distance sufficient to prevent axial movement of the sleeve 90 g in a direction towards the second end 32 b of the coupling member 30 b when operably assembled and/or in a compressed position. An embodiment of an assembled configuration of connector 115 with respect to the sleeve 90 g may involve sliding the sleeve 90 g over the coupling member 30 b in an axial direction starting from the first end 31 b and continuing toward the second end 32 b of the coupling member 30 b until sufficient mechanical interference and/or engagement occurs between the lip 97 g of the sleeve 90 g and frontal edge or mating surface of the coupling member 30 b . The simultaneous rotation/twisting of the sleeve 90 g and the coupling member 30 b may be effectuated in the same or similar manner as described between the sleeve 90 b and the coupling member 30 b.
[0083] FIG. 17 depicts an embodiment of connector 116 . Embodiments of connector 116 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 g , a compression portion 60 , and a radial restriction member 65 c.
[0084] FIG. 18 depicts an embodiment of connector 117 . Embodiments of connector 117 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 g , a compression portion 60 , and a radial restriction member 65 b.
[0085] With reference now to FIG. 19 , embodiments of connector 118 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 f , a compression portion 60 , and a radial restriction member 65 a.
[0086] Embodiments of connector 118 may include an outer sleeve 90 f . Sleeve 90 f may share the same or substantially the same structural and functional aspects of sleeve 90 b . Accordingly, sleeve 90 f may include an engagement member 97 f that is configured to mate or engage with a retaining structure 37 b of the coupling member 30 b . For example, the sleeve 90 f may include a first end 91 f , a second end 92 f , an inner surface 93 f , and an outer surface 94 f , and may be a generally annular member having a generally axial opening therethrough. Additionally, sleeve 90 f may surround the coupling member 30 b , the post 40 , the connector body 50 , or a portion thereof, the compression portion 60 , and a radial restriction member 65 , or a portion thereof when in an assembled and/or compressed position. However, the sleeve 90 f may extend towards the first end 31 b of coupling member 30 b . In one embodiment, the first end 91 f of the sleeve 90 f may be flush or substantially flush with an edge of the coupling member 30 b proximate or otherwise near the first end 31 b of the coupling member 30 b . Moreover, the engagement member 97 f may be located proximate or otherwise near the edge of the first end 91 f of the sleeve 90 f . The engagement member 97 f may be configured to mate or engage a retaining structure 37 b of the coupling member 30 b that is correspondingly located proximate or otherwise near the first end 31 b of the coupling member 30 b.
[0087] FIG. 20 depicts an embodiment of connector 119 . Embodiments of connector 119 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 f , a compression portion 60 , and a radial restriction member 65 c.
[0088] FIG. 21 depicts an embodiment of connector 120 . Embodiments of connector 120 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 f , a compression portion 60 , and a radial restriction member 65 b.
[0089] Referring now to FIG. 22 , embodiments of connector 121 may include a coupling member 30 a , a post 40 , a connector body 50 , an outer sleeve 90 e , a compression portion 60 , and a radial restriction member 65 a.
[0090] Embodiments of connector 121 may include an outer sleeve 90 e . Sleeve 90 e may share the same or substantially the same function as sleeve 90 a and sleeve 90 d . Accordingly, the sleeve 90 e may include a first end 91 e , a second end 92 e , an inner surface 93 e , and an outer surface 94 e , and may be a generally annular member having a generally axial opening therethrough. Sleeve 90 e may surround the coupling member 30 a , the post 40 , the connector body 50 , or a portion thereof, the compression portion 60 , and a radial restriction member 65 , or a portion thereof when in an assembled and/or compressed position. Moreover, the sleeve 90 e may extend towards the first end 31 a of coupling member 30 a . However, sleeve 90 e may include an inwardly extending lip 97 e proximate or otherwise near the first end 91 e of the sleeve 90 e , which can help guide the coupling member 30 a onto a corresponding interface port. The lip 97 e may share the same functional aspects of the engagement member 97 a , 97 d of sleeve 90 a , 90 d , respectively. For instance, the lip 97 e may radially inwardly extend a distance sufficient to prevent axial movement of the sleeve 90 e in a direction towards the second end 32 a of the coupling member 30 a when operably assembled and/or in a compressed position. An embodiment of an assembled configuration of connector 121 with respect to the sleeve 90 e may involve sliding the sleeve 90 e over the coupling member 30 a in an axial direction starting from the first end 31 a and continuing toward the second end 32 a of the coupling member 30 a until sufficient mechanical interference and/or engagement occurs between the lip 97 e of the sleeve 90 e and frontal edge or mating surface of the coupling member 30 a . The simultaneous rotation/twisting of the sleeve 90 e and the coupling member 30 a may be effectuated in the same or similar manner as described between the sleeve 90 a and the coupling member 30 a.
[0091] FIG. 23 depicts an embodiment of connector 122 . Embodiments of connector 122 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 e , a compression portion 60 , and a radial restriction member 65 c.
[0092] FIG. 24 depicts an embodiment of connector 123 . Embodiments of connector 123 may include a coupling member 30 b , a post 40 , a connector body 50 , an outer sleeve 90 e , a compression portion 60 , and a radial restriction member 65 b
[0093] Continuing to refer to the drawings, FIGS. 25-27 depict an embodiment of connector 124 - 128 that may include a coupling member 30 c , a post 40 , a seal member 80 , a connector body 50 , a connector body seal element 5 , a compression portion 60 , and a radial restriction member 65 . Embodiments of a radial restriction member 65 may be radial restriction member 65 a , radial restriction member 65 b , or radial restriction member 65 c.
[0094] Referring to FIG. 25 , embodiments of connector 124 may include a coupling member 30 c , a post 40 , a connector body 50 , a sealing member 80 , a connector body seal element 5 , a compression portion 60 , and a radial restriction member 65 a.
[0095] FIG. 26 depicts an embodiment of connector 125 . Embodiments of connector 125 may include a coupling member 30 c , a post 40 , a connector body 50 , a sealing member 80 , a compression portion 60 , and a radial restriction member 65 c.
[0096] FIG. 27 depicts an embodiment of connector 126 . Embodiments of connector 127 may include a coupling member 30 c , a post 40 , a connector body 50 , a sealing member 80 , a compression portion 60 , and a radial restriction member 65 b.
[0097] With reference to FIGS. 28 and 29 , embodiments of connector 127 - 128 may include a coupling member 30 c , a post 40 , a seal member 80 , a connector body 50 , a sleeve 90 h , a connector body seal element 5 , and a compression portion 260 . Embodiments of a compression portion 260 may be compression portion 260 b or compression portion 260 c.
[0098] FIG. 28 depicts an embodiment of connector 127 . Embodiments of connector 127 may include a coupling member 30 c , a post 40 , a connector body 50 , a connector body seal member 5 , a sleeve 90 h , and a compression portion 260 b.
[0099] Embodiments of connector 127 may include a compression portion 260 b . Compression portion 260 b may be a fastener member that is inserted over the connector body 50 to deformably compress the connector body 50 onto the cable 10 . The compression portion 260 b may have a first end 261 and opposing second end 262 . In addition, the compression portion 260 may include an internal annular protrusion 263 located proximate the first end 261 of the compression portion 260 b and configured to mate and achieve purchase with the annular detent 53 on the outer surface 55 of connector body 50 . Moreover, the compression portion 260 b may comprise a central passageway defined between the first end 261 and second end 262 and extending axially through the compression portion 260 b . The central passageway may comprise a ramped surface 266 which may be positioned between a first opening or inner bore having a first diameter positioned proximate with the first end 261 of the compression portion 260 b and a second opening or inner bore having a second diameter positioned proximate with the second end 262 of the compression portion 260 b . The ramped surface 266 may act to deformably compress the outer surface 55 of a connector body 50 when the compression portion 260 b is operated to secure a coaxial cable 10 . For example, the narrowing geometry will compress squeeze against the cable, when the compression portion is compressed into a tight and secured position on the connector body. Additionally, the compression portion 260 b may comprise an exterior surface feature 269 positioned proximate with or close to the second end 262 of the compression portion 260 b . The surface feature 269 may facilitate gripping of the compression portion 260 b during operation of the connector. Although the surface feature 269 is shown as an annular detent, it may have various shapes and sizes such as a ridge, notch, protrusion, knurling, or other friction or gripping type arrangements. It should be recognized, by those skilled in the requisite art, that the compression portion 260 b may be formed of rigid materials such as metals, hard plastics, polymers, composites and the like, and/or combinations thereof. Furthermore, the compression portion 260 b may be manufactured via casting, extruding, cutting, turning, drilling, knurling, injection molding, spraying, blow molding, component overmolding, combinations thereof, or other fabrication methods that may provide efficient production of the component.
[0100] FIG. 29 depicts an embodiment of connector 128 . Embodiments of connector 128 may include a coupling member 30 c , a post 40 , a connector body 50 , a sealing member 80 , a connector body seal member 5 , a sleeve 90 h , and a compression portion 260 c.
[0101] Embodiments of connector 128 may include a compression portion 260 c . Compression portion 260 c may be an insertable compression sleeve or tubular locking compression member that resides internally with respect to the connector body 50 in the compressed position. The compression portion 260 c may include a first end 261 c , a second end 262 c , an inner surface 263 , and an outer surface 264 c . The compression portion 260 c may be pushed into the connector body 50 to squeeze against and secure the cable 10 . For instance, the compression portion 260 c may protrude axially into an annular chamber through the rear opening, and may be slidably coupled or otherwise movably affixed to the connector body 50 to compress into the connector body 50 and retain the cable 10 . The compression portion 260 c may be displaceable or movable axially or in the general direction of the axis of the connector between a first open position (accommodating insertion of the tubular inner post 40 into a prepared cable 10 end to contact the grounding shield 14 ), and a second clamped position compressibly fixing the cable 10 within the chamber of the connector because the compression portion 260 c is squeezed into retraining contact with the cable 10 within the connector body 50 . Furthermore, the compression portion 260 c may include a lip 265 c proximate the first end 261 c , wherein the lip 265 c of the compression portion 260 c mates with the internal groove of the connector body 50 .
[0102] Further embodiments of a coaxial cable connector may include a coupling member 30 , a post 40 , a connector body 50 , a sealing member 80 , a connector body seal member 5 , a sleeve 90 , a compression portion 60 / 260 , and a radial restriction member 65 a / 65 b / 65 c . Embodiments of sleeve 90 may include sleeve 90 a / 90 b / 90 d / 90 e / 90 f / 90 g / 90 h , or may simply share the same structural and functional aspects, yet be configured to operably attach to a coupling member having molded plastic threads, or a coupling member that is completely molded. Embodiments of a coupling member 30 , which may share the same or substantially the same structural and functional aspects of 30 a / 30 b / 30 c , may include plastic threads designed to seal against the external threads 23 of port 20 to keep moisture and other physical contaminants out. For example, the threads may be cut slightly different resulting in a differently shaped or dimensioned thread from the threads 23 of the port 20 to achieve a seal with the port 20 . Furthermore, the threads could be slightly over-sized causing the metallic threads 23 of the port 20 to slice, pierce, grind, etc., into and against the plastic threads of the plastic coupling member 30 as the plastic coupling member 30 is being threaded onto the port 20 . The threads can be molded or machined, and the coupling member 30 can be all plastic (molded or machined) or the coupling member 30 can have a plastic insert that has molded or cut threads. Additionally, the plastic threads may be shaped like pipe-threads causing the non-pipe-thread-shaped threads of the port 20 to seal against the plastic threads of the coupling member 30 when the coupling member 30 is advanced onto the port 20 . The threads may also include a small protrusion feature running along the threads that forms a seal with the threads of the port 20 as the coupling member 30 is advanced onto the port 20 . Embodiments of a plastic coupling member (or partially plastic coupling member having plastic threads), in addition to creating a physical seal, may inherently create a secure connection to the port 20 because a tight friction-fit may likely be formed with the port 20 as the threads of the coupling member 30 are advanced (with some amount of force that may be necessary to overcome the friction) onto the threads of the port 20 .
[0103] Those skilled in the art should appreciate that various combinations and embodiments disclosed and described in detail herein may include a body seal element, such as connector body seal element 5 , to provide an environmental seal for the coaxial cable connector.
[0104] With reference to FIGS. 1-29 , a method of fastening a coaxial cable, such as coaxial cable 10 , to a communication port, such as port 20 . The method may comprise a step of providing a coaxial cable connector 100 - 128 including: a connector body 50 , a post 40 operably attached to the connector body 50 , the post 40 having a flange 44 , a coupling member 30 a / 30 b / 30 c axially rotatable with respect to the post 40 and the connector body 50 , the coupling member 30 a / 30 b / 30 c including a lip 34 a / 34 b / 36 c , an outer sleeve 90 a / 90 b / 90 c / 90 d / 90 e / 90 f / 90 g / 90 h engageable with the coupling member 30 a / 30 b / 30 c , and a compression portion 60 structurally integral with the connector body 50 . Another method step may include axially compressing the compression portion 60 to form an environmental seal around the coaxial cable 10 , wherein when axially compressed, the compression portion 60 breaks away from the connector body 50 and securely connects to the coaxial cable 10 . Still another method step may include fastening the coupling member 30 a / 30 b / 30 c to an interface port by operating the outer sleeve 90 a / 90 b / 90 c / 90 d / 90 e / 90 f / 90 g / 90 h.
[0105] While this invention has been described in conjunction with the specific embodiments outlined above, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the preferred embodiments of the invention as set forth above are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the invention as defined in the following claims. The claims provide the scope of the coverage of the invention and should not be limited to the specific examples provided herein. | A connector used in coaxial cable communication applications, and more specifically to coaxial connectors having features for sealing against environmental contaminants, facilitating effective attachment to a corresponding interface port, and improving the efficiency of structures and processes for attaching the connectors to coaxial cables. Furthermore, an associated method is also provided. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 11/580,184 filed on Oct. 12, 2006, now U.S. Pat. No. 8,703,240 which claims the benefit of U.S. Provisional Application No. 60/727,755 filed on Oct. 18, 2005. The entire disclosure of each of the above applications is incorporated herein by reference as if fully set forth in detail herein.
FIELD
The present disclosure relates to a method for forming workpieces using tool blades that are coated in a process that uses masking to partly cover the tool blades.
BACKGROUND
This section provides background information related to the present disclosure which is not necessarily prior art.
Many vehicle drivelines include power transmission devices having a number of gears in meshing engagement with one another. Each gear typically includes a plurality of teeth spaced apart from one another to properly mesh with the teeth of another gear. Each gear tooth must be precisely formed to provide reliable power transmission over an extended period of time.
The gears are constructed using gear cutting tools operable to remove material from a gear blank to define the gear teeth. In high volume manufacturing, it is desirable to quickly and accurately cut the gear teeth into a desired finished shape. It is also desirable to minimize the costs associated with constructing such gears. Accordingly, tooling design engineers strive to define manufacturing processes where not only the finished gear is constructed according to specification but where the cutting tools remain sharp for extended periods of time. A number of cutting tool manufacturers have constructed cutting tools from high speed steel, tungsten carbide and other cutting materials. In one instance, tool life has been extended by coating a tungsten carbide tool with a wear resistant material such as titanium aluminum nitride. Titanium nitride may be used as a coating for high speed steel applications. The coating is typically applied by immersing the tool in an environment containing a mixture of gas including titanium aluminum nitride or titanium nitride for six to eight hours. During exposure to the gas mixture, a coating is deposited on all surfaces exposed to this environment. Cutting tools exposed to this process have exhibited up to double the cutting life of similar tools not coated with the wear resistant material.
Once a cutting tool has become dull, it is common practice to grind the tip of the cutting tool to sharpen and/or redefine the cutting edge or edges. Unfortunately, the grinding process removes the coating previously applied to the cutting surfaces. Typically, the entire tool is exposed to the coating process once again to assure that the recently ground surfaces are coated. Because not all of the cutting tool is ground during the sharpening process, most of the cutting tool receives an additional coating thickness of the wear resistant material. It has been found that this grinding and recoating process may be repeated approximately five times until an undesirable result occurs. Specifically, once five or more layers of the coating are accumulated on the non-ground surfaces, the coating no longer properly adheres and causes the tool to fail.
It has been contemplated to remove the coating from the entire cutting tool prior to recoating using a chemical process. The chemical process negatively affects the cutting tool by removing the Cobalt from the cutting tool surface. The carbide microstructure is adversely altered and no longer exhibits the excellent cutting properties for which the tool is designed.
Alternately, it has been contemplated to machine more surfaces of the cutting tool to remove the previous coatings prior to reapplying another coating to the reground cutter. Unfortunately, the additional machining processes are very costly and may negatively interfere with the geometry of the cutting tool and repeatability of the machining operation. Accordingly, a need exists for a method of sharpening and recoating a cutting tool to extend the interval between cutting tool sharpening operations and to increase the number of times a given tool may be sharpened.
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
In one form, the present teachings provide a method for forming a sharpened cutting tool. The method includes: grinding a cutting tip to form an intermediate cutting tool, the cutting tip of the intermediate cutting tool comprising a planar face and a sharpened cutting edge at a distal end of the planar face, the cutting tip being relieved on a side and an end that cooperate with the planar face to define the sharpened cutting edge; masking the intermediate cutting tool such that a first predetermined portion of the planar face is exposed and a second predetermined portion of the planar face is not exposed, the exposed portion of the planar face including the sharpened cutting edge and including at least portions of the end and the side that cooperate to define the cutting edge; and depositing a wear-resistant material onto the exposed portion of the planar face of the intermediate cutting tool to form the sharpened cutting tool.
In another form, the present teachings provide a method for forming a sharpened cutting tool. The method includes: grinding a cutting tip to form an intermediate cutting tool, the cutting tip of the intermediate cutting tool comprising a planar face and a sharpened cutting edge at a distal end of the planar face, the cutting tip being relieved on a side and an end that cooperate with the planar face to define the sharpened cutting edge; masking the intermediate cutting tool such that a first predetermined portion of the planar face is exposed and a second predetermined portion of the planar face is not exposed, the second predetermined portion being spaced apart from the sharpened cutting edge; and depositing a wear-resistant material onto the first predetermined portion of the cutting tip of the intermediate cutting tool to form the sharpened cutting tool, the wear-resistant material not being deposited on the second predetermined portion of the cutting tip of the intermediate cutting tool.
In yet another form, the present teachings provide a method that includes: grinding a cutting tip to form an intermediate cutting tool, the cutting tip of the intermediate cutting tool comprising a planar face and a sharpened cutting edge at a distal end of the planar face, the cutting tip being relieved on a side and an end that cooperate with the planar face to define the sharpened cutting edge; masking the intermediate cutting tool such that a first predetermined portion of the planar face is exposed and a second predetermined portion of the planar face is not exposed, the exposed portion of the planar face including the sharpened cutting edge and including at least portions of the end and the side that cooperate to define the cutting edge; depositing a wear-resistant material onto the exposed portion of the planar face of the intermediate cutting tool to form a sharpened cutting tool; and forming a workpiece, the workpiece being cut with the sharpened cutting tool.
In still another form, the present teachings provide a method that includes: grinding a cutting tip to form an intermediate cutting tool, the cutting tip of the intermediate cutting tool comprising a planar face and a sharpened cutting edge at a distal end of the planar face, the cutting tip being relieved on a side and an end that cooperate with the planar face to define the sharpened cutting edge; masking the intermediate cutting tool such that a first predetermined portion of the planar face is exposed and a second predetermined portion of the planar face is not exposed, the second predetermined portion being spaced apart from the sharpened cutting edge; depositing a wear-resistant material onto the first predetermined portion of the cutting tip of the intermediate cutting tool to form the sharpened cutting tool, the wear-resistant material not being deposited on the second predetermined portion of the cutting tip of the intermediate cutting tool; and cutting a workpiece with the sharpened cutting tool.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.
FIG. 1 is perspective view of an exemplary cutting tool;
FIG. 2 is an exploded perspective view of a fixture operable to hold and mask cutting tools during a coating process;
FIG. 3 is a top view of a portion of the fixture illustrated in FIG. 2 having a plurality of cutting tools positioned therein;
FIG. 4 is an end view of the fixture illustrated in FIG. 2 having a plurality of cutting tools positioned therein;
FIG. 5 is a partial fragmentary plan view of a portion of a cutting tool and a portion of a mask positioned on the cutting tool; and
FIG. 6 is an exploded perspective fragmentary view illustrating alternate embodiment masks.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
Example embodiments will now be described more fully with reference to the accompanying drawings.
FIG. 1 depicts an exemplary cutting tool 10 operable to remove material from a gear blank and form a portion of the gear teeth. Typically, cutting tools are arranged in pairs where the first tool of the pair removes material from one side of the “V-shaped” groove and the other tool having an opposite hand removes material from the opposite side of the same “V-shaped” groove. Depending on the gear to be manufactured, many pairs of cutting tools may be mounted to a cutting head (not shown) to form a gear.
Cutting tool 10 is formed from an elongated bar of tungsten carbide having a rectangular cross-section. Cutting tool 10 includes a gripping portion 12 having a width 14 and height 16 . Gripping portion 12 maintains a substantially rectangular cross-section. Gripping portion 12 includes a top face 18 . A cutting tip 20 is formed at an opposite end of cutting tool 10 from gripping portion 12 . Cutting tip 20 is formed by machining a cutting face 22 at a 12° angle to top face 18 . Cutting tip 20 includes a first side 24 and a second side 26 . The first and second sides terminate at a rounded root cutting portion 28 . The intersection of cutting face 22 and first side 24 forms a cutting edge 30 operable to remove material from the gear blank. Second side 26 is shaped to provide clearance for the opposite hand cutting element (not shown) paired with cutting tool 10 . An edge 32 formed at the intersection of cutting face 22 and second side 26 does not typically remove any material from the gear blank.
As previously described, after a number of gears have been cut, cutting edge 30 dulls. At this time, cutting tool 10 is removed from the gear cutting apparatus and sharpened. During sharpening, the cutting tool is ground along first side 24 , second side 26 and rounded root cutting portion 28 . The grinding forms a sharpened cutting edge 30 . After cutting tool 10 has been sharpened, first side 24 , second side 26 and rounded root cutting portion 28 will no longer be coated by the previously deposited wear resistant coating. Accordingly, sharpened cutting tools are prepared to be exposed to an environment within an enclosed chamber (not shown) to coat cutting edge 30 , first side 24 , second side 26 and rounded root cutting portion 28 with the wear resistant material.
After sharpening, cutting tool 10 is thoroughly cleaned to remove any dirt, oil or metal shavings from the surfaces of the cutting tool 10 . A single sharpened cutting tool 10 or a number of sharpened cutting tools similar to cutting tool 10 are next placed in a fixture 100 illustrated in FIGS. 2-4 . Fixture 100 is operable to accurately align a number of cutting tools relative to one another and mask a majority of the external surfaces of the cutting tools from exposure to an environment containing a wear resistant coating. Fixture 100 is sized to support the cutting tools 10 in the enclosed chamber having a mixture of gases and titanium aluminum nitride and/or titanium nitride coating circulating throughout the chamber. The surfaces exposed to the environment within the chamber are coated with a predetermined thickness of wear resistant material based on the time of exposure to the environment in the chamber.
To assure that less than five thicknesses of wear resistant coating are present on cutting tip 20 at any one time, fixture 100 is sized and shaped to expose only a very limited portion of each cutting tool 10 to the environment within the chamber. Specifically, the surface of the portion of cutting tool 10 that is exposed to the environment approximately corresponds to the portion of cutting tool 10 that would be removed when cutting tool 10 is resharpened. FIG. 5 depicts the amount of cutting face 22 exposed after mounting and masking the cutting tools 10 within fixture 100 . In this manner, only one or two thicknesses of wear resistant coating are on cutting edge 30 at any one time. By maintaining a proper thickness of wear resistant coating, tool life is greatly extended.
Fixture 100 includes a shell 110 , a cover 112 and a mask 114 . Shell 110 is a substantially “U” shaped member having a first side wall 116 , a second side wall 118 and an end wall 120 interconnecting the side walls. End wall 120 includes a substantially planar top surface 122 extending between first side wall 116 and second side wall 118 . First side wall 116 includes a substantially planar upper surface 124 . Second side wall 118 includes a substantially planar upper surface 126 . Upper surface 124 and upper surface 126 are substantially co-planar with one another. Threaded apertures 128 extend transversely through first side wall 116 . Threaded bores 130 are positioned in first side wall 116 and extend through upper surface 124 . Threaded bores 132 are positioned within second side wall 118 . Bores 132 extend through upper surface 126 of second side wall 118 .
Cover 112 is substantially shaped as a plate having a hat-shaped cross-section. Cover 112 includes a body portion 134 and laterally extending flanges 136 . Flanges 136 include lower surfaces 138 . Body portion 134 includes a lower surface 140 . Apertures 142 extend through the thickness of cover 112 . Apertures 142 are sized and positioned to receive threaded fasteners 144 . Threaded fasteners 144 threadingly engage bores 130 and bores 132 formed in shell 110 . Fasteners 144 are operable to clamp cutting tools 10 and mask 114 between top surface 122 of end wall 120 and bottom surface 140 of cover 112 .
Mask 114 is a plate-like structure having a plurality of teeth 150 formed at one end. Each tooth 150 includes a first face 152 and a second face 154 interconnected by a rounded end 156 . First face 152 , second face 154 and rounded end 156 are shaped substantially similarly to first side 24 , second side 26 and rounded root cutting portion 28 of cutting tip 20 . Furthermore, each tooth 150 is spaced apart a distance equivalent to the spacing between adjacent cutting tips 20 of cutting tools 10 when positioned adjacent to one another. As best illustrated in FIG. 4 , each tooth 150 includes an angled back face 158 positioned to engage one of the cutting faces 22 formed on each cutting tool 10 .
After the individual cutting tools 10 have been sharpened, a number of cutting tools are positioned within shell 110 . Cutting tips 20 are aligned along a common plane and then cutting tools 10 are mounted to shell 110 using a pair of threaded fasteners 160 . Threaded fasteners 160 are threadingly engaged with apertures 128 and protrude through first side wall 116 to engage one of the cutting tools positioned within shell 110 . A compressive load is placed on each of the cutting tools via threaded fasteners 160 to secure the cutting tools within the shell.
One skilled in the art will appreciate that any number of manufacturing techniques may be used to align cutting tips 20 along the common plane. For example, a cap 200 may be temporarily coupled to shell 110 to provide a datum surface 202 on which each of the cutting tools are abutted prior to clamping cutting tools 10 to shell 110 . Specifically, cap 200 is a substantially “C” shaped member having a wall 204 interconnecting a first leg 206 and a second leg 208 . First leg 206 includes an aperture 210 extending therethrough for receipt of a fastener 212 . Fastener 212 is threadingly engageable with an aperture 214 formed in first side wall 116 . Similarly, second leg 208 includes an aperture 216 for receipt of another fastener 212 threadingly engaged with an aperture 218 formed in second side wall 118 . Datum surface 202 is formed on wall 204 and spaced apart a predetermined distance “B” from an end surface 230 of shell 110 .
Cap 200 may also be used to properly position mask 114 relative to the cutting tools 10 . Alternatively, mask 114 may include a key or a pin (not shown) to align mask 114 relative to shell 110 at a predetermined location. Because teeth 150 of mask 114 are similarly shaped to cutting tips 20 of cutting tool 10 , mask 114 is axially offset from the plurality of cutting tools 10 such that teeth 150 formed on mask 114 do not completely cover the entire cutting face 22 of each cutting tool 10 . As illustrated in FIG. 5 , rounded end 156 is offset from rounded root cutting portion 28 by a predetermined distance. In the example shown, the predetermined distance is 1 mm. It should be appreciated that this distance may vary depending on the amount of cutting tool that must be removed during each grinding or sharpening process. Furthermore, because rounded end 156 is offset from rounded root cutting portion 28 , a portion of cutting face 22 adjacent cutting edge 30 and edge 32 is exposed to atmosphere. Based on the orientation of the components previously described, each cutting tool 10 will receive a coating of wear resistant material on first side 24 , second side 26 , rounded root cutting portion 28 , cutting edge 30 , edge 32 and a relatively small portion of cutting face 22 .
Once the positioning of cutting tool 10 and mask 114 is completed, fasteners 144 interconnect cover 112 and shell 110 to clamp cutting tools 10 and mask 114 therebetween. The subassembly of cutting tools and fixture 100 are placed within an enclosed vessel and the portions of each of the cutting tools 10 exposed to atmosphere are coated with a predetermined thickness of wear resistant material.
Upon completion of the sharpening and coating processes, the cutting tools are mounted to a cutting head and used to manufacture gears once again. Once the cutting tools 10 are dull, the tools are removed and the sharpening and coating processes are repeated. It should be appreciated that the external surfaces of cutting tools 10 that were previously coated are now removed during the sharpening process. Therefore, an undesirable amount of wear resistant coating is not accumulated at any time through tool life.
An alternate embodiment mask assembly 300 is depicted at FIG. 6 . A plurality of masks 302 are used in conjunction with shell 110 . Each mask 302 is shaped substantially similar to the cutting end of a cutting tool 10 . Each mask 302 is positioned substantially similarly as teeth 150 were positioned relative to cutting tips 20 in the previous embodiment. It is contemplated that masks 302 may be used in place of mask 114 and vice versa.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. | A method in which a cutting tip is ground to form an intermediate cutting tool; a first predetermined portion of the intermediate cutting tool is masked; a wear-resistant material is deposited onto the exposed portion of the intermediate cutting tool to form a sharpened cutting tool; and a workpiece is cut with the sharpened cutting tool. | 2 |
INTRODUCTION
Heat exchangers incorporating apparatus of the present invention have been developed for use with large gas turbines for improving their efficiency and performance while reducing operating costs. Heat exchangers of the type under discussion are sometimes referred to as recuperators, but are more generally known as regenerators. A particular application of such units is in conjunction with gas turbines employed in gas pipe line compressor drive systems.
Several hundred regenerated gas turbines have been installed in such applications over the past twenty years or so. Most of the regenerators in these units have been limited to operating temperatures not in excess of 1000° F. by virtue of the materials employed in their fabrication. Such regenerators are of the plate-and-fin type of construction incorporated in a compression-fin design intended for continuous operation. However, rising fuel costs in recent years have dictated high thermal efficiency, and new operating methods require a regenerator that will operate more efficiently at higher temperatures and possesses the capability of withstanding thousands of starting and stopping cycles without leakage or excessive maintenance costs. A stainless steel plate-and-fin regenerator design has been developed which is capable of withstanding temperatures to 1100° or 1200° F. under operating conditions involving repeated, undelayed starting and stopping cycles.
The previously used compression-fin design developed unbalanced internal pressure-area forces of substantial magnitude, conventionally exceeding one million pounds in a regenerator of suitable size. Such unbalanced forces tending to split the regenerator core structure apart are contained by an exterior frame known as a structural or pressurized strongback. By contrast, the modern tension-braze design is constructed so that the internal pressure forces are balanced and the need for a strongback is eliminated. However, since the strongback structure is eliminated as a result of the balancing of the internal pressure forces, the changes in dimension of the overall unit due to thermal expansion and contraction become significant. Thermal growth must be accommodated and the problem is exaggerated by the fact that the regenerator must withstand a lifetime of thousands of heating and cooling cycles under the new operating mode of the associated turbo-compressor which is started and stopped repeatedly.
Confinement of the extreme high temperatures in excess of 1000° F. to the actual regenerator core and the thermal and dimensional isolation of the core from the associated casing and support structure, thereby minimizing the need for more expensive materials in order to keep the cost of the modern design heat exchangers comparable to that of the plate-type heat exchangers previously in use, have militated toward various mounting, coupling and support arrangements which together make feasible the incorporation of a tension-braze regenerator core in a practical heat exchanger of the type described.
Heat exchangers of the type generally discussed herein are described in an article by K. O. Parker entitled "Plate Regenerator Boosts Thermal and Cycling Efficiency", published in The Oil & Gas Journal for Apr. 11, 1977.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to heat exchangers of the plate-and-fin type and, more particularly, to a support system for a multi-ton heat exchanger mounted within a steel support structure.
2. Description of the Prior Art
Various arrangements are known in the prior art for supporting displaceable devices of substantial weight. Some of these arrangements depend upon support members in compression, others in tension, still others by balancing levers and weights. The R. C. Allen U.S. Pat. No. 1,814,627 for example discloses a turbine support system comprising three fixed support points and additional yieldable points to assume a portion of the load. The yieldable support points include fulcrums with levers and counterweights for weight distribution.
The economizer of the Armacost U.S. Pat. No. 2,069,515 comprises a plurality of superposed tubes interconnected by bolts and suspended by tube fins from fixed beams. The Short U.S. Pat. No. 2,876,975 discloses heat exchanger apparatus supported by tubes. Expansion is permitted by elongated openings for support fastenings.
The Yurko U.S. Pat. No. 3,236,295, Kotzebue U.S. Pat. No. 2,195,887, Hickey et al U.S. Pat. No. 3,273,636 and Lortz U.S. Pat. No. 3,982,902 are examples of arrangements utilizing suspension rods with pivoting or swivel couplings to accommodate displacement of a member being supported. Hochmuth et al U.S. Pat. No. 3,434,531 discloses a semi-rigid tube supporting tie comprising overhead hangers connecting the load member to fixed support beams. The Hennig U.S. Pat. No. 2,420,135 discloses a plurality of flexible bars extending tangentially to an expandable member which is to be supported. The Rees U.S. Pat. No. 3,951,108 discloses a plurality of links interconnected by pins in slotted openings to accommodate movement by balancing load and displacement from one point to another. The French Pat. No. 1,208,629 apparently discloses a hanger coupled by rods to pivot points and frame support members.
It appears that none of the prior art discussed hereinabove is concerned with the support of a structure which is subject to significant thermal growth in all three dimensions. Thus, none of the arrangements disclosed in the cited prior art appears to possess the capability of satisfactorily supporting a heat exchanger core of the type involved herein.
SUMMARY OF THE INVENTION
In brief, arrangements in accordance with the present invention comprise a plurality of flexible members coupled to the heat exchanger core and suspended at upper pivotable mounting points from a plurality of balance beams. These beams in turn are pivotably supported from stationary support beams secured to the steel support structure enclosing the heat exchanger. By virtue of this combination of balance beams and flexible support members, the heat exchanger core is free to grow both in length and in width without restraint from the support structure. The suspension arrangement also accommodates vertical growth of the heat exchanger core by virtue of the manner of attachment of the support system to the core, near either the top or bottom of the core, as mounted.
In one particular arrangement in which the core is oriented horizontally, the suspension system comprises a plurality of flexible straps pivotably mounted to overhead balance beams which in turn are pivotably mounted to the overhead support beams. The flexible straps extend downwardly through spaces in the core to pivotably mounted support pads at the underside of the core.
In another particular arrangement in accordance with the present invention, wherein the heat exchanger core is vertically oriented, as mounted, the support system comprises a combination of support beams, balance beams pivotably mounted to the support beams, and a plurality of flexible links extending downwardly from the balance beams and connected to projecting ears or brackets which are attached to the core at the upper side thereof.
BRIEF DESCRIPTION OF THE DRAWING
A better understanding of the present invention may be had from a consideration of the following detailed description, taken in conjunction with the accompanying drawing in which:
FIG. 1 is a partially exploded view in perspective of a heat exchanger module in which embodiments of the present invention are employed;
FIG. 2 is a schematic representation in perspective of one particular arrangement in accordance with the present invention;
FIG. 3 is a view showing details of a component employed in the arrangement of FIG. 2;
FIG. 4 is a sectional view taken along the line 4--4 of FIG. 2 and looking in the direction of the arrows;
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 2 and looking in the direction of the arrows;
FIG. 6 is a schematic view in perspective, similar to the view of FIG. 2, of another particular arrangement in accordance with the invention;
FIG. 7 is a view of particular details of the arrangement of FIG. 6 and is taken along the line 7--7 of FIG. 6; and
FIG. 8 is a view showing a portion of the structure of FIG. 7, viewed from the right-hand side thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
As present constructed, heat exchangers utilizing arrangements in accordance with the present invention are fabricated of formed plates and fins assembled in sandwich configuration and brazed together to form core sections. Such core sections 10 are assembled in groups of six (referred to as "six-packs") as shown in FIG. 1 to form a core 12 which, together with associated hardware, comprises a single heat exchanger module 20. A single module 20 is preferably joined with one other module to make up a regenerator. A plurality of regenerators may be utilized to develop a complete heat exchanger system of the desired capacity.
In the operation of a typical system employing a regenerator of the type discussed herein, ambient air enters through an inlet filter and is compressed to about 100 to 150 psi, reaching a temperature of 500° to 600° F. in the compressor section of an associated gas turbine (not shown). It is then piped to the regenerator module 20, entering through the inlet flange 22a (FIG. 1) and inlet duct 24a. In the regenerator module 20, the air is heated to about 900° F. The heated air is then returned via outlet duct 24b and outlet flange 22b to the combustor and turbine section of the associated turbine via suitable piping. The exhaust gas from the turbine is at approximately 1000° to 1100° F. and essentially ambient pressure. This gas is ducted through the regenerator 20 as indicated by the arrows labelled "gas in" and "gas out" (ducting not shown) where the waste heat of the exhaust is transferred to heat the air, as described. Exhaust gas drops in temperature to about 600° F. in passing through the regenerator 20 and is then discharged to ambient through an exhaust stack. In effect, the heat that would otherwise be lost is transferred to the inlet air, thereby decreasing the amount of fuel that must be consumed to operate the turbine. For a 30,000 hp turbine, the regenerator heats 10 million pounds of air per day.
The regenerator is designed to operate for 120,000 hours and 5000 cycles without scheduled repairs, a lifetime of 15 to 20 years in conventional operation. This requires a capability of the equipment to operate at gas turbine exhaust temperatures of 1100° F. and to start as fast as the associated gas turbine so there is no requirement for wasting fuel to bring the system on line at stabilized operating temperatures. The use of the thin formed plates, fins and other components making up the brazed regenerator core sections contribute to this capability. However, it will be appreciated that there is substantial thermal growth in all three dimensions (length, width and height) as a result of the extreme temperature range of operation and the substantial size of the heat exchanger units. As an example, the overall dimensions of the module 20 shown in FIG. 1, in one instance, were approximately 17 feet in width, 12 feet in length (the direction of gas flow) and 7.5 feet in height. The weight of the core approximated 35,000 pounds.
Referring particularly to FIG. 2, the heat exchanger core 12 may be seen to be supported from two pairs of main cross beams 14 and 16 which are tied together by tie plates 15 and 17, respectively. The beams 14, 16 are affixed at one end to the forward frame structure 19 (FIG. 1) and are secured lengthwise but mounted by means of slots to rearward frame structure 18 in order to permit thermal growth in the width dimension.
The first pair of main cross (or cold support) beams 14 pivotably support, by means of a trunnion or pivot pin 23, a first balance beam 25 from which extend a pair of flexible Inconel straps 26 connected by pins 28 to the balance beam 25.
The second pair of main cross (or hot support) beams 16 support by pivot pins 32 a pair of balance beams 34. A pair of flexible Inconel straps 36 is attached to its associated balance beam 34 by means of pin connections 38. Each of the Inconel straps 26 and 36 extends downwardly through a narrow space between adjacent core sections 10 to associated support pads such as 40. As shown in FIG. 3, the support pad 40 comprises a casting 42 having a pivot pin 44 for attachment to the strap 26 or 36. An insulating strip 46 is mounted on the upper side of the support pad 40 and the adjacent core sections 10 bear against this insulating strip 46. The casting 42 and strip 46 define a slot 47 for receiving the lower end of the flexible strap 26 or 36 for attachment via the pivot pin 44.
The cold support beams 14 are on the cold (gas exit) side of the left-to-right center line of the core 12 and the hot support beams 16 are on the opposite side of the core center line where the hot exhaust gases enter the core. Adjacent core sections 10 are secured together by bars and straps welded about their periphery except at the manifold portions where expandable sealing members (not shown) are provided to accommodate thermal growth. The balance beam 25 is longer than the balance beam 34, sufficient to straddle a pair of central core sections 10 and, with its associated straps 26, provide the support for the weight of the core 12 to one side of the center line. The balance beams 34 each straddle a corresponding core section 10 and provide support for that core section and the two sections adjacent. The hot support beams 16 on the gas inlet side of the core center line are slightly closer thereto than are the cold support beams 14. Since the side of the heat exchanger 12 supported by the balance beams 34 and straps 36 is the gas inlet side, it operates at higher temperatures than the side supported by the balance beam 25 and straps 26. The inlet side experiences greater thermal growth than the outlet side and the multiple balance beam and support strap structure 34, 36 serves to accommodate this greater expansion from thermal growth at the higher temperatures encountered.
Further structural details of the support structure of FIG. 2 are shown in the sectional views of FIGS. 4 and 5. These show a balance beam 34 suspended between the main cross beams 16 by means of a pivot pin or trunnion 32. The pivot pin 32 is held in position by doubler plates 52 affixed as by welding to the beams 16 and by cotter pins 54.
The flexible straps are pivotably supported from the balance beam 34 by means of pivot pins 38 mounted in the ends of the beam 34 and threaded at their outer end to receive a retaining nut 56 and washer 58. Shims 59 are provided on both sides of each strap 36 to position the straps properly on the pivot pin 38 so the straps extend downwardly through the centers of the spaces between the associated core sections 10.
The arrangement of the balance beam 25 and its associated straps 26 is identical to that shown in FIGS. 4 and 5, except that the beam 25 is slightly more than twice the length of one of the beams 34.
By virtue of this support arrangement, growth of the core 12 in a direction aligned with gas flow is accommodated by the pivoted supports at opposite ends of the straps 26, 36. The shift in weight of the core during thermal expansion in this direction during operation is balanced by the differences of off-center positioning of the main support beams 14 and 16 relative to the center line of the core, as described above.
The flexible straps 26 and 36 permit thermal growth of the core in a direction from left to right as shown in FIG. 2 by bending or flexing to the extent needed to accommodate this growth. The pivotable mounting of the balance beams 25 and 34 permits the support structure to accommodate the shift in weight resulting from thermal growth in this direction, thus maintaining substantially balanced forces on the support beams 14 and 16 without transmitting undue lateral stresses to this structure. Since the support of the core 12 is applied at the under side and space is provided at the upper side thereof, the core can grow in a vertical direction without any interference from the support structure.
FIGS. 6-8 show details of a similar mounting arrangement for a heat exchanger core 12' oriented in the vertical direction (rotated 90° from the core 12 shown in FIGS. 1 and 2). In this arrangement, a single pair of main cross beams 60 is provided, mounted at their opposite ends to corresponding structure of the frame and case (not shown) in a manner similar to that described for the structure of FIGS. 1 and 2. The cross beams 60 support a pair of first balance beams 62, coupled thereto by pivot pins 64. Each of the balance beams 62 in turn supports a pair of orthogonally directed, second balance beams 66 suspended from rods 68. Each of the second balance beams 66 in turn supports a series of links 70 which is attached at the lower end thereof by a pivotable mounting 72 to a projecting ear or bracket 74 affixed to the core 12' at a juncture between adjacent core sections 10'.
Referring to FIGS. 7 and 8, it will be seen that the pivot pin 64 mounting the first balance beam 62 to the cross beams 60 is held in position by plates 80 and cotter pins 82. The rod 68 extending downwardly from the first balance beam 62 to the second balance beam 66 is provided at its opposite ends with rocker pins 84, 86 which are oriented to permit pendulum-like movement of the rod 68 relative to the beams 62, 66 without binding.
The series 70 of links extending between the second beam 66 and the core bracket 74 comprises first and second sets of connectors 90, 92. The first set 90 is shown comprising an inverted U-bolt 94 secured to the beam 66 by nuts 96 and washers 98. A second, elongated U-bolt 100 is linked with the U-bolt 94 and supports a cross plate 102, held in position by nuts and washers 96, 98. A similar, inverted elongated U-bolt 100 is linked through an opening in the ear or bracket 74 attached to the heat exchanger core. Each of the plates 102 of the elongated U-bolts 100 is threaded through its center and a rod 106 is mounted in supporting relationship therein.
The second set 92 of vertical support links comprises an apertured strap 110 mounted in a slot of the beam 36 and welded thereto. A similar strap 112 is secured, as by welding, to the heat exchanger core as part of the bracket 74. Each of the straps 110, 112 is threaded by an associated U-bolt 14 having corresponding plates 116 fastened thereon. A rod 118 extends between threaded openings in the centers of the plates 116.
This arrangement of the two sets 90, 92 of supporting links oriented as shown permits the respective U-bolts and rods to be mounted closely adjacent each other without interference between them.
The combination of the balance beams and sets of links in the support system for the vertical mounting arrangement of FIGS. 6-8 effectively supports the heat exchanger core 12' while permitting thermal growth in all three dimensions without distortion of the core or unbalancing of the applicable force distribution. The roller action of the rocker pins 84, 86 and the relatively pivotable connections between the respective links in the sets of the suspension members 90, 92 accommodate displacement in length and width dimensions without development of undue lateral stress. The action of the first and second balance beams automatically accommodates any shift in weight distribution due to thermal growth. Since the core 12' is suspended from the core support brackets 74 along the upper side of the core with sufficient space for expansion being provided underneath the core, the core 12' is free to expand in the vertical direction without interference from the support system and adjacent structure.
The heat exchanger core support systems of the present invention advantageously provide the necessary support for the substantial weight of a large heat exchanger core in a manner which effectively accommodates the thermal growth experienced in operation without restraint relative to the heat exchanger case. By virtue of the flexibility of the hangers and the balancing capability of the support beams connected thereto, any shift in force direction and the balancing of weight distribution during expansion and contraction of the heat exchanger core from thermal variations during operation are readily accommodated. The various components making up the support system are relatively simple in construction and means of attachment, and are readily susceptible to field maintenance, where necessary. Alternative arrangements are provided for heat exchangers mounting the core in horizontal and vertical attitudes with equal effectiveness.
Although there have been described above specific arrangements of a heat exchanger support system in accordance with the invention for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated that the invention is not limited thereto. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention as defined in the appended claims. | Arrangements for supporting a heat exchanger core within a steel frame structure by a hanger system utilizing flexible members pivotably coupled to overhead support beams. Balancing beams are employed to equalize the load transmitted through the system to the support beams. These support systems permit the heat exchanger core to expand in all directions from thermal growth without restraint relative to the frame structure, thereby minimizing thermal fatigue. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a semiconductor circuit, and particularly to a semiconductor circuit used in CATV (CAble TeleVision) hybrid IC (HIC).
[0003] 2. Description of the Related Art
[0004] In HIC (hybrid IC) broadband amplifiers for CATV, a plurality of stages of amplifiers are connected in series via coaxial cable, and a desired gain slope must be established across the entire employed frequency band to correct for characteristic lost in the coaxial cable. Gain slope is such that gain increases with higher frequencies within the bandwidth.
[0005] Realization of desired gain slope in the frequency bands employed has become more difficult in recent years as the frequency bandwidths that are used have extended to higher frequencies.
[0006] [0006]FIG. 1 and FIG. 2 are circuit diagrams showing the configuration of circuits for realizing a desired gain slope used in the prior art as disclosed in Japanese Utility Model laid-open application No. 85810/83.
[0007] In the circuits shown in FIG. 1 and FIG. 2, a parallel resonant circuit is formed by inductor L 101 , which is provided in a bias feedback circuit, and capacitor C 102 , which is provided between the base and emitter of transistor Tr 101 . In addition, damping resistor R 106 connected in a series with capacitor C 102 between the base and emitter of transistor Tr 101 is provided to control Q in the resonant circuit.
[0008] In a circuit configured according to the foregoing description, the resonance frequency is altered by changing the element constants of inductor L 101 and capacitor C 102 , thereby regulating the peaking frequency.
[0009] [0009]FIG. 3 and FIG. 4 are circuit diagrams showing the configuration of circuits for realizing a desired gain slope used in the prior art as disclosed in Japanese Patent Laid-open No. 264404/89.
[0010] In the circuit shown in FIG. 3, a serial resonant circuit is formed by capacitor C 112 and inductor-L 11 in an interstage circuit provided between two amplifier circuits, and in the circuit shown in FIG. 4, FET (Field Effect Transistor) Tr 113 is provided such that inductor L 111 is connected in parallel between the source and drain, and a parallel resonant circuit is formed by inductor L 111 and the capacitance between the source and drain of FET Tr 113 .
[0011] In the circuits configured according to the foregoing description, alteration of resonance frequency is realized by changing the gate bias to vary the capacitance between the source and drain of FET Tr 113 , thereby regulating peaking frequency.
[0012] However, the above-described circuits of the prior art have the following drawbacks:
[0013] (1) In the circuits shown in FIG. 1 and FIG. 2, resonance frequency is altered by changing the element constants of inductor L 101 and capacitor C 102 to regulate the peaking frequency, but the impedance on the input side and output side change according to the amount of peaking because inductor L 101 and capacitor C 102 are provided in the feedback circuit.
[0014] The resulting circuit therefore has the three factors of input and output impedance and gain slope, and design and adjustment consequently require considerable time and trouble.
[0015] (2) In the circuits shown in FIG. 3 and FIG. 4, the resonance frequency is changed and the peaking frequency adjusted by changing the gate bias to change capacitance between the source and drain of the FET, and these circuits therefore require a variable bias to allow change of the gate bias. These circuits also require the additional provision of an FET. As a result both the scale and cost of the circuit is increasing.
[0016] In the circuit shown in FIG. 3, moreover, capacitor C 111 and inductor L 111 between active elements must also be changed to alter the resonance frequency, and mismatching between elements having gain tends to cause problems in characteristics such as oscillation and instability.
SUMMARY OF THE INVENTION:
[0017] The object of the present invention is to provide a semiconductor circuit that can realize a stable gain slope without increasing the circuit scale or necessitating extra time for correcting impedance.
[0018] In this invention, a resonant circuit is provided outside a feedback loop for effecting peaking at a particular frequency and for realizing a gain slope having a desired inclination, for example, an inclination of 1 dB or more. As a result, the oscillation operation need not be considered when designing the circuit.
[0019] In addition, in a case in which a resonant circuit is provided in the output stage of a feedback loop, change in impedance occurs only on the output side and change in impedance does not occur on the input side. A circuit can therefore be designed and adjusted while considering only two factors and without taking the input side into consideration, thereby facilitating adjustment.
[0020] Finally, the invention does not entail enlargement of circuit scale because additional active elements are not necessary.
[0021] The above and other objects, features, and advantages of the present invention will become apparent from the following description based on the accompanying drawings which illustrate examples of preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] [0022]FIG. 1 is a circuit diagram showing the configuration of a circuit for realizing a desired gain slope used in the prior art as disclosed in Japanese Utility Model laid-open No. 85810/83.
[0023] [0023]FIG. 2 is a circuit diagram showing the configuration of a circuit for realizing a desired gain slope used in the prior art as disclosed in Japanese Utility Model laid-open No. 85810/83.
[0024] [0024]FIG. 3 is a circuit diagram showing the configuration of a circuit for realizing a desired gain slope used in the prior art as disclosed in Japanese Patent Laid-open No. 264404/89.
[0025] [0025]FIG. 4 is a circuit diagram showing the configuration of a circuit for realizing a desired gain slope used in the prior art as disclosed in Japanese Patent Laid-open No. 264404/89.
[0026] [0026]FIG. 5 is a circuit diagram showing a semiconductor circuit according to the first embodiment of the present invention.
[0027] [0027]FIG. 6 shows one example of the configuration of chip inductance that including a capacitance component.
[0028] [0028]FIG. 7 is an equivalent circuit diagram of the chip inductance shown in FIG. 6.
[0029] [0029]FIG. 8 shows the gain characteristic with respect to frequency for a case in which a resonant circuit is not applied in the circuit shown in FIG. 5.
[0030] [0030]FIG. 9 shows the gain characteristic with respect to frequency in the circuit shown in FIG. 5.
[0031] [0031]FIG. 10 is a circuit diagram showing a semiconductor circuit according to the second embodiment of the present invention.
[0032] [0032]FIG. 11 is a circuit diagram showing a semiconductor circuit according to the third embodiment of the present invention.
[0033] [0033]FIG. 12 is a circuit diagram showing a semiconductor circuit according to the fourth embodiment of the present invention.
[0034] [0034]FIG. 13 is a circuit diagram showing a semiconductor circuit according to the fifth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0035] First Embodiment
[0036] [0036]FIG. 5 is a circuit diagram showing a semiconductor circuit according to the first embodiment of the present invention. This circuit is only the alternating-current portion of the semiconductor circuit of this invention.
[0037] As shown in FIG. 5, this embodiment is made up of FET Q 1 having its gate terminal connected to the input terminal and its source terminal connected to ground; resistor R 1 and capacitor C 1 connected in a series between the drain terminal and gate terminal of FET Q 1 ; and capacitor C 2 and inductor L 1 connected in parallel between the output terminal and the drain terminal of FET Q 1 ; wherein a feedback loop is formed by FET Q 1 , resistor R 1 , and capacitor C 1 . This feedback loop is provided for maintaining the band and impedance.
[0038] In a semiconductor circuit configured according to the foregoing description, peaking is brought about by the resonance brought about by inductor L 1 and capacitor C 2 , and as a result, the resonance frequency can be changed and a desired slope, for example, of 1 dB or more, can be conferred upon gain by altering the element constants of this inductor L 1 and capacitor C 2 .
[0039] In this embodiment, although impedance changes because the constants of elements constituting the circuit are altered, only impedance on the output side undergoes change because the circuit that generates resonance is provided outside the feedback loop, and impedance on the input side does not change.
[0040] As a result, this embodiment can reduce the time and trouble required in designing and adjusting as compared with the circuits shown in FIG. 1 and FIG. 2 in which impedance changes on both the input side and output side.
[0041] This invention can also dispense with the need for variable bias for altering the gate bias of the FET shown in FIG. 3 and FIG. 4, because the resonance frequency is modified by simply altering the constants of elements. As a result, a slope can be imposed on gain without increasing circuit scale. In addition, oscillation resulting from mismatching of impedance does not occur because the alteration of element constants does not take place in interstage elements.
[0042] Although inductor L 1 and capacitor C 2 are connected in parallel in this embodiment, peaking can be similarly effected if these elements are connected in a series.
[0043] In the semiconductor circuit configured as described hereinabove, the resonant circuit composed of inductor L 1 and capacitor C 2 can also be constituted only by chip inductance that includes a capacitance component.
[0044] [0044]FIG. 6 shows an example of the configuration of chip inductance including a capacitance component, and FIG. 7 is an equivalent circuit diagram of the chip inductance shown in FIG. 6.
[0045] As shown in FIG. 6, the chip inductance of this example includes internal conductors that constitute the L component that are linked in a number of layers in a helical spring form in a ceramic unit with the portions that constitute the C component interposed between the conductors. A resonant circuit including an L component and C component is thus formed as shown in FIG. 7.
[0046] [0046]FIG. 8 shows the gain characteristic with respect to frequency for a case in which a resonant circuit is not applied in the circuit shown in FIG. 5, and FIG. 9 shows the gain characteristic with response to frequency in the circuit shown in FIG. 5.
[0047] As shown in FIG. 9, the circuit shown in FIG. 5 realizes a gain slope having a desired inclination of, for example, 1 dB or more in a desired frequency band.
[0048] Second Embodiment
[0049] [0049]FIG. 10 is a circuit diagram showing a semiconductor circuit according to the second embodiment of the present invention. This circuit is only the alternating-current portion of the semiconductor circuit of this invention.
[0050] As shown in FIG. 10, this embodiment is made up of: FET Q 1 having its gate terminal connected to the input terminal and its source terminal connected to ground; resistor R 1 and capacitor C 1 connected in a series between the drain terminal and gate terminal of FET Q 1 ; FET Q 2 having its gate terminal connected to the drain terminal of FET Q 1 and its source terminal connected to ground; resistor R 2 and capacitor C 3 connected in a series between the drain terminal and gate terminal of FET Q 2 ; and capacitor C 2 and inductor L 1 connected in parallel between the output terminal and the drain terminal of FET Q 2 ; wherein a first feedback loop is formed by FET Q 1 , resistor R 1 , and capacitor C 1 ; and a second feedback loop is formed by FET Q 2 , resistor R 2 , and capacitor C 3 .
[0051] In a semiconductor circuit configured as described hereinabove, the circuit generating resonance is provided outside the feedback loops, and as a result, only the output side impedance changes and the input side impedance does not change, as in the circuit described in the first embodiment. This construction allows a reduction of the time and trouble necessary for designing and adjusting the circuit.
[0052] Third Embodiment
[0053] Although two feedback loops are formed in the circuit shown in FIG. 10, a similar effect can be obtained with only one of the feedback loops.
[0054] [0054]FIG. 11 is a circuit diagram showing a semiconductor circuit according to the third embodiment of the present invention. This circuit is only the alternating-current portion of the semiconductor circuit of this invention.
[0055] As shown in FIG. 11, the resonant circuit constituted by inductor L 1 and capacitor C 2 in this embodiment is provided outside the feedback loop constituted by FET Q 1 , resistor R 1 , and capacitor C 1 . As a result, only the output side impedance changes and the input side impedance undergoes no change, whereby the time and trouble required for design and adjustment can be reduced.
[0056] Although the feedback loop is constituted by FET Q 1 , resistor R 1 , and capacitor C 1 in this embodiment, the same effect can be obtained if the feedback is formed using FET Q 2 if the resonant circuit is provided outside the feedback loop.
[0057] Fourth Embodiment
[0058] The same effect can be obtained in the circuit shown in FIG. 10 even in the case of a feedback loop that effects feedback from the drain terminal of FET Q 2 to the gate terminal of FET Q 1 .
[0059] [0059]FIG. 12 is a circuit diagram showing a semiconductor circuit according to the fourth embodiment of the present invention.
[0060] In the embodiment shown in FIG. 12, only the output side impedance changes and the input side impedance undergoes no change because the resonant circuit constituted by inductor L 1 and capacitor C 2 is provided outside the feedback loop constituted by FET Q 1 and Q 2 , resistor R 1 , and capacitor C 1 . This embodiment therefore reduces the time and trouble required for design and adjustment.
[0061] Although a circuit has been described in this embodiment in which FETs were connected in two stages, the invention is not limited to two FETs, and the same effect can be obtained in a case in which a plurality of FETs are connected in multiple stages as long as the resonant circuit is provided outside the feedback loop.
[0062] Fifth Embodiment
[0063] [0063]FIG. 13 is a circuit diagram showing the semiconductor circuit according to the fifth embodiment of the present invention.
[0064] As shown in FIG. 13, inputted signals in this embodiment are distributed into two differing signals, the two distributed signals are each amplified by amplifier circuit 12 and 13 , and the signals amplified by amplifiers 12 and 13 are then synthesized and outputted.
[0065] Transformer T 1 grounded by way of capacitors C 34 and C 35 is provided as a distributing means that distributes signals inputted by way of input terminal 1 into two signals of different phase, and transformer T 2 that is grounded by way of capacitor C 37 is provided as a synthesizing means for synthesizing the two signals amplified by amplifiers 12 and 13 .
[0066] Amplifier circuit 12 is made up of: FETs Q 11 -Q 13 connected in multiple stages; thermistor Rt 11 and resistor R 13 connected together in parallel and provided as the gate resistance of FET Q 11 , the second FET; inductor L 13 provided between the gate terminal of FET Q 11 and a connection point between thermistor Rt 11 and resistor R 13 ; resistor R 11 , capacitor C 11 , and thermistor Rt 12 connected in a series between the gate terminal, i.e., the input of amplifier circuit 12 , and the drain terminal of FET Q 12 ; resistor R 12 and capacitor C 12 connected in a series between the drain terminal of FET Q 12 and a prescribed potential; capacitor C 13 connected between the drain terminal of FET Q 12 and the other connection point between thermistor Rt 11 and resistor R 13 ; inductor L 11 and resistor R 17 connected in a series between the drain terminal of FET Q 12 and the source terminal of FET Q 11 ; capacitor C 15 connected between the connection point between inductor L 11 and resistor R 17 and the prescribed potential; resistor R 14 , capacitor C 14 , and thermistor Rt 13 connected in a series between the drain terminal of FET Q 12 and the drain terminal of FET Q 13 ; resistor R 16 connected to the gate terminal of FET Q 13 ; and resistor R 15 , inductor L 12 , and capacitor C 16 provided connected in parallel between the drain terminal of FET Q 13 and the output terminal of amplifier circuit 12 ; the drain terminal of FET Q 11 and the source terminal of FET Q 13 being connected.
[0067] Amplifier circuit 13 is made up of: FETs Q 21 -Q 23 connected in multiple stages; thermistor Rt 21 and resistor R 23 connected together in parallel and provided as the gate resistance of FET Q 21 , the second FET; inductor L 23 provided between the gate terminal of FET Q 21 and a connection point between thermistor Rt 21 and resistor R 23 ; resistor R 21 , capacitor C 21 , and thermistor Rt 22 connected in a series between the gate terminal, i.e., the input of amplifier circuit 13 , and the drain terminal of FET Q 22 ; resistor R 22 and capacitor C 22 connected in a series between the drain terminal of FET Q 22 and a prescribed potential; capacitor C 23 connected between the drain terminal of FET Q 22 and the other connection point between thermistor Rt 21 and resistor R 23 ; inductor L 21 and resistor R 27 connected in a series between the drain terminal of FET Q 22 and the source terminal of FET Q 21 ; capacitor C 25 connected between the connection point between inductor L 21 and resistor R 27 and a prescribed potential; resistor R 24 , capacitor C 24 , and thermistor Rt 23 connected in a series between the drain terminal of FET Q 22 and the drain terminal of FET Q 23 ; resistor R 26 connected to the gate terminal of FET Q 23 ; and resistor R 25 , inductor L 22 , and capacitor C 26 provided connected in parallel between the drain terminal of FET Q 23 and the output terminal of amplifier circuit 13 ; the drain terminal of FET Q 21 and the source terminal of FET Q 23 being connected.
[0068] The gate terminal of FET Q 13 and the gate terminal of FET Q 23 are connected by way of resistors R 16 and R 26 .
[0069] On the input side of transformer T 1 are provided: capacitor C 33 and inductor L 31 connected in a series between transformer T 1 and input terminal 1 , capacitor C 31 and resistor R 31 connected in a series between the connection point between capacitor 33 and inductor L 31 and the prescribed potential, and capacitor C 32 connected between the connection point between capacitor 33 and inductor L 31 and the prescribed potential; and on the output side of transformer T 2 are provided: inductor L 32 and capacitor C 39 connected in a series between transformer T 2 and output terminal 2 , and capacitor C 38 connected between the connection point between inductor L 32 and capacitor C 39 and the prescribed potential.
[0070] In addition, between amplifier circuit 12 and amplifier circuit 13 are provided: resistor R 41 connected between the source terminal of FET Q 11 and the source terminal of FET Q 21 , resistors R 39 and R 40 connected in a series between the gate terminal of FET Q 11 and the gate terminal of FET Q 21 , resistors R 33 and R 34 connected in a series between the connection point between resistor R 39 and resistor R 40 and transformer T 1 , resistor R 32 and thermistors Rt 31 and Rt 32 connected in a series between the connection point between resistor R 33 and transformer T 1 and the prescribed potential, resistor R 35 connected between the prescribed potential and the connection point between resistor R 34 and the connection point between resistors R 39 and R 40 , resistor R 37 connected between the source terminal of FET Q 12 and the source terminal of FET Q 22 , resistor R 36 connected between the source terminal of FET Q 12 and the prescribed potential, resistor R 38 connected between the source terminal of FET Q 22 and the prescribed potential, resistors R 42 and R 43 connected between transformer T 2 and the connection point between resistor R 16 and resistor R 26 , resistor R 44 and capacitor C 40 connected in parallel between the prescribed potential and the connection point between resistor R 42 and R 43 , and capacitor C 36 connected between the prescribed potential and the connection point between resistor R 42 and transformer T 2 ; and power supply voltage Vdd is impressed to the connection point between resistor R 33 and resistor R 34 as well as to the connection point between resistor R 42 and transformer T 2 .
[0071] Thermistors Rt 11 , Rt 21 , and Rt 31 are thermally sensitive resistance elements in which resistance changes with a negative temperature characteristic according to the ambient temperature, and thermistors Rt 12 , Rt 13 , Rt 22 , Rt 23 , and Rt 32 are thermally sensitive resistance elements in which resistance changes with a positive temperature characteristic according to the ambient temperature.
[0072] In a semiconductor circuit configured according to the foregoing description, peaking is brought about by resonance generated by inductor L 12 and capacitor C 16 (similarly, by resonance generated by inductor L 22 and capacitor C 26 ). As a result, the resonance frequency can be changed by changing the element constants of-this inductor L 12 and capacitor C 16 (similarly, the element constants of inductor L 22 and capacitor C 26 ), and moreover, Q can be controlled by resistors R 15 and R 25 for Q damping, and gain can therefore be set to a slope of 1 dB or more.
[0073] In this embodiment, impedance changes because the constants of elements that constitute the circuit are changed, but only the output side impedance changes and the input side impedance undergoes no change. Because the resonant circuit constituted by inductor L 12 and capacitor C 16 is provided outside the feedback loop that uses FETs Q 11 -Q 13 in amplifier circuit 12 and the resonant circuit constituted by inductor L 22 and capacitor C 26 is provided outside the feedback loop that uses FETs Q 21 -Q 23 in amplifier circuit 13 .
[0074] The embodiment therefore enables a reduction of time and trouble in design and adjustment.
[0075] In addition, modification of the resonant frequency by altering the element constants obviates the need for variable bias for altering the gate bias of the FET, whereby a slope can be set to gain without increasing the scale of the circuit. Further, oscillation due to mismatching of impedance does not occur because alteration of the element constants does not take place in interstage elements.
[0076] In this embodiment, thermistors Rt 11 and Rt 21 having a negative temperature characteristic are provided as the gate resistance of FETs Q 11 and Q 21 , respectively.
[0077] In amplifier circuit 12 , fluctuations in gain characteristic with respect to ambient temperature in the gain slope that is generated in the resonant circuit constituted by inductor L 12 and capacitor C 16 are thus canceled out by fluctuations in the value of Q with respect to ambient temperature in the circuit constituted by capacitor C 13 , thermistor Rt 11 , and inductor L 13 , and the inclination of the gain slope outputted from amplifier circuit 12 is therefore uniform despite variations in the ambient temperature.
[0078] Similarly, in amplifier circuit 13 , fluctuations in gain characteristic with respect to ambient temperature in the gain slope that is generated in the resonant circuit constituted by inductor L 22 and capacitor C 26 are canceled out by fluctuations in the value of Q with respect to ambient temperature in the circuit constituted by capacitor C 23 , thermistor Rt 21 , and inductor L 23 , and the inclination of the gain slope outputted from amplifier circuit 13 is therefore uniform despite variations in the ambient temperature.
[0079] In this embodiment, thermistors Rt 31 and Rt 32 are connected in a series between prescribed potential and the connection point between resistor R 33 and transformer T 1 .
[0080] As a result, the current in the vicinity of a prescribed temperature is therefore at a minimum, and the circuit current increases as the ambient temperature falls from the prescribed temperature and also increases as the ambient temperature rises from the prescribed temperature, thereby enabling prevention of deterioration of distortion characteristic due to change in temperature.
[0081] In this embodiment, moreover, resistor R 43 having a resistance of 10-100 Ω is provided between resistor R 42 and the connection point between resistor R 16 and resistor R 26 , and capacitor C 40 is provided between the prescribed potential and the connection point between resistor R 42 and resistor R 43 , the circuit constants of these components being set according to termination conditions.
[0082] Thus, in the case in which fluctuation in potential occurs at point A in the figure, the fluctuation in potential (wave) is absorbed by resistor R 43 , and a standing wave is not generated, thereby enabling prevention of deterioration by even distortion (principally CSO) that is caused by the standing wave.
[0083] While preferred embodiments of the present invention have been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims. | Realizing a stabilized gain slope without increasing circuit scale or entailing extra time or care for correcting impedance. A resonant circuit that is made up of a capacitor and an inductor is provided in an output stage outside a feedback loop for realizing peaking at a particular frequency and for realizing a gain slope having a desired slope of, for example, 1 dB or more. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a track and bogie for wheel based suspended vehicles. Vehicles provided with at least two of said bogies form together with said track a transportation system. In particular the invention is useful for public transportation often denoted as PRT (personal rapid transit).
BACKGROUND OF THE INVENTION
[0002] The problems with transporting the large and increasing number of people living in cities are well known. Public transportation with large vehicles in the form of metro, trolley and buses all have the problem with people having to wait for vehicles to arrive and then stop at all stations during the trips. Cars offer the flexibility of a personal trip but have problems with pollution, accidents, congestion and land use. A transit system which offers the flexibility of the car without its drawbacks is widely known as PRT.
[0003] Many PRT systems have been described and patented. These systems can be characterized as having rotating motors driving on wheels or linear motors. The wheel traction based systems have problems with loss of traction in some weather conditions while the linear electric motor systems have an economic and efficiency problem, as linear electric motors are in general more expensive and less efficient than rotating electric motors. For large vehicle systems like trains the uncertain traction can be compensated with long headways, i.e. inter-vehicle times. This is not possible for a system with small vehicles as the reduced track capacity would make the system economically infeasible.
[0004] Vehicles of PRT systems can further be characterized as either supported on the track or suspended under the track. One main advantage with a suspended system is to avoid accumulation of snow, water or debris on the running surfaces of the track. A suspended system can achieve this by having only one track opening, facing downwards, greatly reducing the risk of foreign particles entering the track.
[0005] Many previous PRT systems have been designed with cabins suspended under the track. One main problem with this type of configuration is that the running surfaces on each side of the track opening must be kept at a constant lateral distance. This is structurally complicated as the track usually has a rather high U-shape internally to allow vehicles to pass. This problem is compounded by the fact that a vehicle is subjected to lateral forces acting on the cabin. These lateral forces translate to torsional moments which tend to pry the track open, i.e. to increase the width of the track opening. To avoid this the track must be made stiff, which increases its weight, cross-section size and cost.
[0006] To implement a PRT system a possibility to individually switch each vehicle to a selected track at switch points is required. Many systems having an on board switch mechanism have been designed and patented. Such designs have the advantage of allowing switching without moving parts in the track. A problem with this type of switch mechanism, particularly for a suspended vehicle configuration, is to maintain the possibility to transfer above mentioned torsional moments from the vehicle cabin to the track at all times when negotiating switches.
[0007] U.S. Pat. No. 3,830,163 describes a PRT system. A vehicle of said prior art PRT system does not have separate guide and switch wheels, which means that switching movement must be performed when the guide/switch wheels are under pressure from torsional moments, causing wear of wheels and tracks, noise and excessive energy use. In addition the system has drive wheels bearing down on an upwards facing surface of the track, an arrangement which does not provide a safe traction as stated above. Furthermore the switch mechanism of said disclosure has a downwards facing central rail which prevents the use of upwards facing drive wheels.
SUMMARY OF THE INVENTION
[0008] The present invention includes a transportation system track with straight, transition, curved, and switch sections. The invention further comprises bogies for vehicle cabins suspended under said track. Track sections of the track have an upper rail referred to as first track member and one or two lower rails referred to as second track members. Straight and curved track sections have one lower rail on the left or right side, as made appropriate by the side preferred for placing cantilevered posts upholding the track. Transition sections have two lower rails, left and right, and are used between two straight or curved track sections having opposite side lower rails. Switches have two lower rails on the common route and one each on the two alternate routes of the switch. Furthermore, in switch sections, these lower rails are special in that while maintaining engagement with respective load bearing wheels of a bogie guided by said track they no longer engage the lower guide wheels of the bogie. This arrangement allows the bogie to select a left or a right alternate route out of the switch by positioning switch wheels of the bogie appropriately, as will be described below.
[0009] Bogies of a preferred configuration have two sets of upper guide and switch wheels, and one set of lower guide and switch wheels. They also have one left and one right load bearing wheel and one drive wheel facing upwards, engaging a downwards facing running surface of the first track member. Each set of lower guide wheels consist of left and right wheel pairs so that transition sections can be passed without moving any parts of the bogie. Switch wheels are separate from guide wheels so that they can be positioned according to the preferred direction of travel well before reaching a switch.
[0010] According to one aspect of the invention a track with the characteristics of the enclosed claim 1 is presented.
[0011] According to a further aspect of the invention a suspended bogie with the characteristics of the enclosed independent claim 8 is presented.
[0012] According to a further aspect of the invention a vehicle based on said suspended bogie is presented in claim 20 .
[0013] According to a further aspect of the invention a transportation system comprising said track and said suspended bogie is presented as claim 21 .
[0014] Further aspects and embodiments of the invention are presented in the dependent claims.
[0015] The present invention preferably uses rotating electric motors and ensures the most reliable friction possible by locating the running surface receiving the drive wheel facing downwards inside a mostly enclosed first track member provided with a downward facing opening. The contact force of a drive wheel of a bogie when engaging the drive wheel running surface can be adjusted using a servo mechanism. The contact force is adjusted to accommodate different drive/brake force requirements and coefficients of friction, thus preventing any significant slippage of the drive wheels while minimizing the rolling resistance in each drive wheel.
[0016] A vehicle being guided along the track of the track system comprises a cabin suspended from two or more of the bogies described herein, said bogies arranged in line, one after the other, wherein the two or more bogies of a vehicle are coupled to each other.
[0017] Advantages accomplished by means of the invention are:
a minimization of the drawback with respect to possible loss of friction when using a rotating electric motor so that short inter-vehicle headways can be achieved with maintained system safety in all weather conditions. a minimization of energy loss due to rolling resistance. a reduction of the risk of accumulation of snow, water or debris inside the track. elimination of the above mentioned adverse effects of torsional moments, whereby a reduction of track weight, cross-section size and cost compared to other systems is achieved. allowing a network or mesh type of track layout where vehicles can select paths at each switch using an on board switch mechanism, this switch mechanism being able to transfer torsional moments from the vehicle cabin to the track at all times when negotiating switches.
DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a sectional view of a bogie on a straight track section.
[0024] FIG. 2 is a perspective view of a bogie on a straight track section with the switch in a neutral position.
[0025] FIG. 3 is a perspective view of a switch showing a bogie set to run in a left direction out from the switch.
[0026] FIG. 4 is a perspective view of switch showing a bogie set to run in a right direction out from the switch.
[0027] FIG. 5 is a perspective view from below of a bogie in the switch, bound left as shown in FIG. 3 .
[0028] FIG. 6 is a perspective view from below of a bogie in the switch, bound right as shown in FIG. 4 .
[0029] FIG. 7 is a side view of a bogie showing the upwards facing drive unit.
DETAILED DESCRIPTION OF EMBODIMENTS
[0030] In the following embodiments of the invention will be described more in detail with reference to the enclosed drawings.
[0031] In FIG. 1 a preferred embodiment of a bogie is shown on a straight track section consisting of an upper u-shaped track member, the first track member 1 , and a lower track member, referred to as the second track member 101 , in this case arranged to the left in the direction of travel. These first 1 and second 101 track members are fixedly connected to each other, for instance using ribs ( 110 , see FIG. 2 ) and preferably enclosed in a u-shaped cover with a downwards facing opening (not shown).
[0032] A bogie 40 has a bogie frame 50 holding left and right load bearing wheels 150 , 250 . In the shown embodiment, the left load bearing wheel 150 is in contact with the upwards facing surface 101 a of the left second track member 101 , thus transferring the downwards directed force from the bogie to the track. The bogie 40 is provided with upper guide wheels 151 a , 151 b , 251 a , 251 b carried by the bogie frame 50 . The purpose of said upper guide wheels 151 a , 151 b , 251 a , 251 b is to keep the bogie aligned with the track at an upper level, i.e. at the level of the first track member 1 . Attached to the bogie is, further, a set of left lower guide wheels 152 , 153 including a left inner guide wheel 152 and a left outer guide wheel 153 with the purpose of keeping the bogie aligned with the track at a lower level, i.e. at the level of the second track member. Correspondingly, attached to the bogie is a set of right lower guide wheels 252 , 253 including a right inner guide wheel 252 and a right outer guide wheel 253 with the purpose of performing the same task as the set of left lower guide wheel 152 , 153 in a track section where a right second track member (not shown) is present. Alternatively, the track may be provided with a right second track member along the main part of the track and the bogie then being guided by said right lower guide wheels 252 , 253 along the main part of the track and guided by said left lower guide wheels 152 , 153 in a track section where a left second track member 101 is present.
[0033] The first track member 1 of the track provides an upper set of a first 16 wheel running surface and a second 17 wheel running surface facing each other in an inwards direction. Said wheel running surfaces 16 , 17 are the inner surfaces of the flanges of a downwards facing U-shaped beam. The web of said U-shaped beam connecting said flanges has a downwards directed drive wheel running surface 15 for receiving the drive wheel of a bogie 40 .
[0034] The second track member 101 of the track provides a lower set of wheel running surfaces including an upwards facing surface 101 a , a first outwards directed surface 101 b on a lateral side of said second track member 101 and a second inwards directed surface 101 c on an opposite lateral side of said second track member 101 , wherein said lower set of wheel running surfaces are offset in relation to a vertical plane intersecting a centre line between the upper set of wheel running surfaces. The term “centre line” is herein meaning a line which along the track is located between the wheel running surfaces 16 , 17 of the first track member 1 at an equal distance to said wheel running surfaces 16 , 17 . This fact is herein referred to simply that the second track member 101 is laterally offset in relation to the first track member 1 .
[0035] The first 1 and second 101 track members are rigidly connected to each other by means of ribs 110 (shown schematically in FIG. 2 ) at regular distances along the track. Said ribs keep the first and second track members at an equal distance along the track. Preferably, the first and second track members are made of steel and welded or bolted to the ribs.
[0036] A vehicle made for running along said track has a cabin suspended from at least two bogies 40 , where said bogie on its part is suspended from the track having said first 1 and said second 101 track member.
[0037] A set of left lower guide wheels 152 , 153 include said first lower guide wheel 153 located to run along a first lateral surface 101 b of said second track member 101 and said second lower guide wheel 152 located to run along a second lateral surface 101 c of said second track member 101 .
[0038] A set of right lower guide wheels 252 , 253 include said first lower guide wheel 253 located to run along a first lateral surface 201 b of said second track member 201 and said second lower guide wheel 252 located to run along a second lateral surface 201 c of said second track member 201 .
[0039] A set of upper guide wheels includes: said first upper guide wheels 151 a , 151 b being located to run along a first inwards directed running surface, herein called a first guide surface 16 of said first track member 1 and second upper guide wheels 251 a , 251 b being located to run along a second inwards directed running surface, herein called a second guide surface 17 of said first track member 1 , wherein as stated said first 16 and second 17 guide surfaces face each other.
[0040] In a transportation system including a vehicle and the track for said vehicle, it is often a requirement to have the ability to switch the vehicle into different track routes at a switch section of the track. Hereinafter switching a vehicle bogie 40 in a switch section will be described. In FIG. 2 an aft switching shaft 51 b (in the direction of bogie travel) can be seen. A corresponding fore switching shaft 51 a can be seen in FIG. 7 . The shaft 51 b is pivotally connected to the bogie frame 50 by upper and lower bearings 55 b , 56 b (in FIG. 1 ) and holds an aft upper switch wheel holder 52 b on which a left upper switch wheel 154 b and a right upper switch wheel 254 b , are mounted. Corresponding components in the fore can be seen in FIG. 7 , wherein it is disclosed that the shaft 51 a is pivotally connected to the bogie frame 50 by upper and lower bearings 55 a , 56 a , and wherein the fore shaft 51 a holds a fore upper switch wheel holder 52 a on which, in the fore end of the bogie, a left upper switch wheel 154 a and a right upper switch wheel 254 a , are mounted. The fore and aft switching shafts 51 a , 51 b can thus control engagement of the upper switch wheels by rotation of said shafts. The shafts 51 a , 51 b are forced to rotate by a switch drive (not shown), both shafts being connected to a switch plate 54 which performs an arc shaped mostly lateral movement, left or right, to perform switching. As a consequence of the arrangement, fore and aft shafts 51 a , 51 b will rotate in opposite directions upon movement of the switch plate 54 . Lower switch wheel swingers 155 , 255 are also engaged by the switch plate 54 so that they rotate synchronously with the lower switch cranks 53 a , 53 b , and also with the upper switch wheel holders 52 a , 52 b via the switch shafts 51 a , 51 b . Accordingly, upper switch wheels 154 a , 254 a , 154 b , 254 b are also rotated synchronously with the switching shafts 51 a , 51 b . Outer lower switch wheels 156 , 256 are mounted on their respective lower switch wheel swingers 155 , 255 while inner lower switch wheels 157 , 257 are mounted directly on the bogie frame 50 . The switch plate 54 can perform the arched movement as it is attached to three equal length crank functions at 301 , 302 , 303 . The switch crank 53 b is connected to the switch plate 54 by a pin in a slot arrangement 304 of the switch plate forcing the crank 53 b and, via the switching shaft 51 b , also the upper switch holder 52 b to rotate in the opposite direction to the aforementioned three cranks functions 301 , 302 , 303 (See also FIG. 7 ).
[0041] The lower switch wheels include a left outer switch wheel 156 attached to a left swinger 155 and a right outer switch wheel 256 attached to a right swinger 255 , wherein said left and right swingers are pivotally attached to said switch plate 54 by means of a crank functions 301 , 303 and pivotally attached to the frame 50 , whereby the left outer switch wheel 156 will rotate inwards towards the frame 50 when the right outer switch wheel 256 rotates outwards away from the frame 50 , and vice versa, upon a movement of the switch plate 54 .
[0042] In FIG. 3 a bogie is approaching a switch from an entry point 305 and has its switch mechanism positioned to go to the left switch exit 306 . When the bogie 40 reaches the starting point of lower switch rails 102 , 202 the left lower outer switch wheel 156 will continue on the outer (left) side of the left lower switch rail 102 while the right lower outer switch wheel 256 will continue on the inside of the right lower switch rail 202 , thus forcing the bogie to continue towards the left switch exit 306 at the lower vertical level. At the same time the upper left switch wheels 154 a , 154 b engage the left side of a downwards extended left flange 103 of the first track member 1 while the upper right switch wheels 254 a , 254 b continue on the inside of a downwards extended right flange 203 , thus forcing the bogie to continue towards the left switch exit 306 at the higher vertical level. As the right lower switch rail 201 has a notch at position 204 lower right guide and switch wheels 253 , 256 , 257 are not blocked from following the straight path to the left switch exit 306 . The fact that both upper and lower switch wheels work together to force the bogie towards the left switch exit 306 ascertains that any torsional moments that may be acting on the bogie 40 while it passes the switch can be transferred to the track, i.e. that the bogie is not allowed to rotate around a longitudinal axis even in the presence of such moments. Despite the denominations entry and exit used it is as feasible for a bogie to enter the switch from opposite directions at position 306 or position 307 and continue towards position 305 as well as going in the direction described here.
[0043] The lower switch rails 102 , 202 are rigidly connected to the lower track members 101 , 201 and the upper track member 1 by means of ribs similar to 110 at regular intervals within the switch section (not shown).
[0044] FIG. 4 is very similar to FIG. 3 but in this figure the bogie 40 has its switch mechanism positioned to go to the right exit 307 of the switch. The right lower switch wheel swinger 255 has been rotated such that it has become positioned further away outwards from the centre of the bogie so that the right lower outer switch wheel 256 will pass on the outer (right) side of the right lower switch rail 202 . As the right lower switch rail 202 is formed as a curve bending away, in a direction to the right, from the longitudinal direction of the track, the bogie is forced to follow the track towards the right exit 307 at the lower vertical level. At the same time the upper switch wheel holders 52 a , 52 b have been synchronously rotated, whereby the right upper switch wheels 254 a , 254 b have become correspondingly positioned further away outwards, to the right, from the centre of the bogie, so that said right upper switch wheels 254 a , 254 b will pass on the outside of a downwards extended right flange 203 of the first track member 1 , thus forcing the bogie 40 to continue towards the right switch exit 307 at the higher vertical level. As the left lower rail 101 has a notch at position 104 of the drawing, lower left guide and switch wheels 153 , 156 , 157 are not blocked from following the curved path towards the right switch exit 307 .
[0045] FIG. 5 shows a bogie 40 on its way towards the left switch exit 306 . In this position the left upper switch wheels 154 a , 154 b are on the outside of the downwards extended left flange 103 of the upper track member 1 and together with the left upper guide wheels 151 a , 151 b they force the bogie to continue towards the left switch exit 306 at an upper level. The right upper switch wheels 254 a , 254 b are on the inside of the downwards extended right flange 203 of the upper track member 1 and can travel unhindered towards the left switch exit 306 . The left lower outer switch wheel 156 is on the outside of the left lower switch rail 102 and together with the left lower inner switch wheel 157 it forces the bogie to continue towards the left switch exit 306 at a lower level. At this longitudinal position the lower guide wheels 153 , 253 are disengaged from the lower track members 101 , 201 thanks to the notches at positions 104 and 204 and can pass towards the left switch exit 306 without being engaged by said lower track members. The right lower outer switch wheel 256 has been rotated inwards, so that it can pass through the notch at position 204 towards the left switch exit 306 along with the right lower inner switch wheel 257 .
[0046] FIG. 6 shows a bogie 40 on its way towards the right switch exit 307 . In this position the right upper switch wheels 254 a , 254 b have been rotated as described above in relation to FIG. 4 , so that they are running on the outside of the downwards extended right flange 203 of the upper track member 1 and together with the right upper guide wheels 251 a , 251 b they force the bogie towards the right switch exit at 307 in the upper level. The left upper switch wheels 154 a , 154 b pass on the inside of the downwards extended left flange 103 of the upper track member 1 and can travel unhindered towards the right switch exit 307 . The right lower outer switching wheel 256 is correspondingly positioned on the outside of the lower right switch rail 202 and together with the right lower inner switch wheel 257 it forces the bogie 40 to continue towards the right switch exit 307 at the lower level. The lower guide wheels 153 , 253 are disengaged from the lower track members 101 , 201 in this longitudinal position thanks to their notches at positions 104 , 204 and can thus pass towards the right switch exit 307 . The left lower switch wheel 156 has been rotated inwards to the right by means of left switch wheel swinger 155 so that it can pass through the notch at position 104 towards the right switch exit 307 along with the left lower inner switch wheel 157 .
[0047] FIG. 7 shows one preferred drive mechanism utilizing a so called wheel motor symbolized by a drive wheel 57 which engages the downwards facing drive wheel running surface 15 (in FIG. 1 .) of the first track member 1 . The periphery of the wheel motor has a rubber coating or similar intended to increase friction. The normal force between the wheel motor and said drive wheel running surface 15 can be adjusted using a pressurizer actuator 59 here shown in the shape of a hydraulic cylinder, although the function could just as well be performed by an electric motor with some kind of gear box and a crank or excenter function. The force exerted by the pressurizer actuator is transferred to the wheel motor by means of a drive wheel pressurizer 58 shown here as a lever mechanism. The pressurizer 58 rotates around a first joint at 308 when the pressurizer actuator 59 moves it. This movement is transferred to the wheel motor by a second joint at 309 , thus (mainly) changing the compression of the rubber coating of the wheel motor, which in turn affects the normal force of the drive wheel against the running surface 15 as intended. | The present invention includes a track ( 1, 101 ) of a track system with straight, transition, curved, and switch track sections. The invention further comprises bogies ( 40 ) for vehicle cabins suspended under the track. Track sections of the track have an upper rail ( 1 ) and one or two lower rails ( 101, 201 ). Further, a bogie ( 40 ) has fore and aft sets of upper guide and switch wheels ( 151, 251, 154, 254 ), and one set of lower guide and switch wheels ( 152, 153, 252, 253, 156, 157, 256, 257 ). The bogies ( 40 ) also have one left and/or one right load bearing wheel ( 150, 250 ) and one drive wheel facing upwards and engaging a downwards directed drive wheel running surface ( 15 ) of the upper rail. Each set of lower guide wheels consist of left and right wheel pairs ( 152, 153, 252, 253 ) so that transition sections can be passed without moving any parts of the bogie ( 40 ). Switch wheels ( 154, 254, 156, 157, 256, 257 ) are separated from guide wheels so that they can be positioned according to the preferred direction of travel well before reaching a switch. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority benefits to Chinese Patent Application No. 200810079978.6 filed Dec. 9, 2008, the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to cutting bits for wall breaking, tunneling, trenching, coal mining, and road milling machines, and more particularly to a tool comprising more than one ancillary cutting tip in additions to a main cutting tip.
[0004] 2. Description of the Related Art
[0005] Most popular conventional bits for breaking or excavating machines are generally comprised of an alloy steel bit body and a carbide alloy bit tip. The carbide alloy bit tip is welded to the head of the bit body using soldering technology. During cutting or breaking, the head of the cutter undergoes strong stresses and is subjected to friction. Thus, the bit body around the carbide alloy bit tip will progressively wear out, generally resulting in the falling off of and catastrophic failure of the bit tip. In underground coal mining application, sparks are created when the tool collides with the rock. Spark must be reduced or eliminated for safety reasons. Various technologies have been developed to elongate the service lifetime of the tool, while trying to improve the safety and penetrating ability thereof. Currently, a majority of cutting bits adopts the three structures shown in FIGS. 1-3 . Still, 85 percent failures of the tools adopting the above mentioned designs are due to a fall-off of the carbide tip, resulting from a wear out of the steel body.
[0006] German Patent DE19821147A1 discloses a cutting tool design ( FIG. 4 ). The design suggests installing wear-resistant elements around the main cutting tip. However, the design is not optimized, and there is still much room for improvement. Although the design reduces the wear out of the steel body to some extent, it also shows the following weaknesses:
The front area disposed toward the working direction has to be widened to accommodate the additional wear resistant elements. The shoulder of the bits with such arrangement becomes wide and square, which brings about the problem of heavy pounding and high power consumption. The flat top surface of the claimed cylindrical wear resistant body also increases resistance against the tool during work. In addition, the sharp right-angled edges of the wear resistant elements are fragile and break easily in collision with the material to be removed. The breakage diminishes the protection effect of the elements. The necessary length of the wear resistant body, as well as radius to height ratio of the cylindrical wear resistant element, have not been elucidated or optimized. From what is illustrated in the drawings, the radius to height ratio of the cylindrical wear resistant element is very close to 1:1. Obviously, elements with such a configuration can only provide only limited protection to the square part of the tool shoulder. However, in practical working conditions, the entire front part of the tool is often buried beneath the material to be removed. The material to be removed will wear against the front part of the tool, including the metal around and beneath the bottom of the wear resistant element. In this case, the short fat wear resistant element will rapidly lose support and fall out due to wear out of the surrounding metal (see FIG. 13 ). As a result, such configuration actually cannot provide lasting protection for the steel tool body.
[0010] There have been other solutions adopting slimmer and longer wear resistant elements than the above mentioned German patent. However, these solutions can only prolong the service life to a limited extend, while they do not give satisfying results life respect to the problems discussed above.
SUMMARY OF THE INVENTION
[0011] Therefore, it is one objective of the present invention to provide a bit tool for breaking or excavating machines capable of increasing the wear resistance capability without sacrificing its penetrating ability so as to extend the service lifetime of the bit, as well as increase its working efficiency and safety.
[0012] To achieve the above objective, there is provided a cutting bit for breaking or excavating machines, comprising: a tool body; a main tip; and a plurality of ancillary tips, the ancillary tips comprising a plurality of tapered cutting tips or a plurality of cutting edges for breaking operation; and the ancillary tips being disposed on the tool body around the main bit tip.
[0013] In certain embodiments of the present invention, the cutting tips of the ancillary tips are in shape of a cone, a frustum, a semi-ellipsoid or a dome, e.g., a spherical dome, with the sectional area of the ancillary tips becoming smaller along their axis.
[0014] In certain embodiments of the present invention, the cutting edges of the ancillary tips are single-wedge or multiple-wedge.
[0015] In certain embodiments of the present invention, the ends of the cutting tips are installed above the front surface of the tool body.
[0016] In certain embodiments of the present invention, the ends of the cutting edge are installed above or flush with the front surface of the tool body.
[0017] In certain embodiments of the present invention, the ratio between the ancillary tips radius and length is in the range of between 1:1.5 and 1:5.
[0018] In certain embodiments of the present invention, between 3 and 50 ancillary tips are installed around the main tip.
[0019] In certain embodiments of the present invention, between 6 and 20 ancillary tips are installed around the main tip.
[0020] In certain embodiments of the present invention, the buried length of the ancillary tip is more than one third of the length of the main tip.
[0021] In certain embodiments of the present invention, the buried length of the ancillary tip is more than one third of the maximum diameter of the main tip.
[0022] In certain embodiments of the present invention, the buried parts of the ancillary tips body are in shape of a cylinder, a cone, or a truncated cone.
[0023] In certain embodiments of the present invention, the main tip is made of a first material; the ancillary tips are made of a second material; the tool body is made of a third material; and the first material is harder than the third material; and the second material is harder than the third material.
[0024] The present invention provides the following solution for the buried length of the ancillary tips:
a) For tools with plug-type main tip, the buried length of the ancillary tips must be more than one third of that of the main tip. b) For tools with cap-type main tip, the buried length of the ancillary tips must be more than one third of the maximum diameter of the main tip.
[0027] The ancillary tips in the present invention constitute an essentially different concept from the wear resistant element described in DE19821147A1. The wear resistant elements in DE19821147A1 are provided mainly in order to provide limited protection to the square part of the tool shoulder. Meanwhile, the notch formed during cutting can, to some extend, help in rotating the tool before it falls out. However, in DE19821147A1 not much attention was paid to the side effects brought about by the extended shoulder area, which is necessary to accommodate the cylindrical element. For example, the widened shoulder part causes turbulent flow of power and pounding vibration of the machine.
[0028] In DE19821147A1 and CN 200610102129.9, a flat shoulder is necessary to accommodate the wear resistant elements. This flat shoulder can cause a large resistant force against the cutting tool during its operation. The increased resistant force is harmful. Firstly, it will overload the machine, thus causing extra impact and vibration, which is likely to damage the machine. Secondly, it will increase the power consumption. Thirdly, it will produce vast easily flammable coal dust, thus reducing safety. The ancillary tips of this invention provide ideal solution to these problems. The tapered ancillary tips are engaged in cutting work together with the main tip. The tapered tip cuts through the bulk material without causing extra resistant force. Under the same working conditions, the energy consumption of a machine equipped with the tool of this invention is only 50% of the energy consumption of a machine equipped with a tool described in DE19821147A1 or CN 200610102129.9.
[0029] The ancillary tips of the present invention do not have a cylindrical or conical body. The top surface pointed to the working direction is not flat. Rather, the ancillary tips are in the shape of a cylinder with tapered tip, a dome, a cone, a wedge, a mushroom, or the like. The ancillary tips not only act as passive wear resistant member, but also are actively involved in breaking the material to be removed.
[0030] Comparison tests were carried out between embodiments of the present invention and those described in DE19821147A1 and CN 200610102129.9. The results of test shown below indicate that the former have obvious advantage over the latter.
[0031] Conditions of coal mine tests:
[0000]
Coal seam hardness f = 6.
Mining depth: 0.6 m
Mining height: 4 m
Shearer haulage speed: 7.7 m/min
Working face length: 100 m
Shearer drum speed: 28 rpm
[0032] Normally, a miner uses a traditional single tipped tool. Because coal seams are relatively hard, the tool consumption is large. The traditional tools cannot survive a workload of cutting through a full working face having 100 m in length. On average, 89 bits will be consumed in an 8 hours shift. The average output is about 2000 T per shift. 400 pieces of tools of each type were provided to a coal miner for test.
[0033] 1. Comparison Test of Tools Described DE19821147A1:
[0034] Single tipped tools were replaced by the tools constructed according to DE19821147A1. As soon as the shearer was started, the monitoring system indicated the machine was working in an overloaded condition. The tool caused great resistance due to a widened shoulder area. The tools could not penetrate into the coal bulk smoothly; instead, the tools stroke the bulk like hammer. The pounding effect caused heavy coal dust and great vibration of the shearer. The machine operator had to shut off the shearer. In order to carry on the test, the operator had to readjust the shearer working parameters as follows: shearer haulage speed was slowed down to: 4.0 m/min; shearer drum speed was lowered to 19 rpm; and the mining depth remained at 0.6 m. The test was carried on by sacrificing the working efficiency. After the adjustment, the operator managed to maneuver the shearer working at the limit below overloading. Although the wear resistant elements provided some extent of protection to the tool body, they started to suffer breakage soon after start of operation. Some of the wear resistant members started to fall off after the shearer worked though 95 m along the working face. The main tips started to drop out after 120 m. Then the machine had to be stopped for tool replacement. The test lasted 4 working shifts (32 hours). Totally, 276 pieces of tools had to be changed, that is 69 pieces had to be changed every working shift, on average. During the test, coal production output was about 2100 T every working shift.
[0035] 2. Comparison Test of Tools According to CN 200610102129.9
[0036] After replacing the tools prepared according to DE19821147A1 with those described in CN 200610102129.9, the shearer operator restored the parameter as follows: shearer haulage speed at 7.7 m/min; shearer drum speed at 28 rpm; the mining depth remained at 0.6 m. At the initial stage, the similar problem appeared as in the previous test. The operator had to readjust the machine the same way as in the previous test, that is, shearer haulage speed was slowed down to: 4.0 m/min; shearer drum speed was lowered to 19 rpm; and the mining depth remained at 0.6 m. Similar to the former test, the wear resistant elements started to suffer breakage soon after operation. However, the elements were held strongly in position because they were embedded deeper into the tool body. As the front tool body around the wear resistant element has worn out, the tool front shoulder disappeared and the tool front became slimmer. When the shearer reached 80 m along the working face, the operator noticed that the working load decreased due to the better penetrating performance of tool. Then the operator restored the parameter to normal settings as follows: shearer haulage speed at 7.7 m/min; shearer drum speed at 28 rpm; the mining depth remained at 0.6 m. A few wear resistant members started to fall off after the shearer fed in 160 m along the working face. Main tips started to drop out after 200 m. Then the machine had to be stopped for tool replacement. The test lasted 4 working shifts (32 hours). Totally, 220 pieces of tools had to be changed, that is 55 pieces had to be changed every working shift in average. During the test, coal production output is about 2350 T every working shift.
[0037] Although this test gives a better result than the previous test, ancillary tips, which can actively get engaged in cutting operation, were adopted for further comparison test.
[0038] 3. Comparison Test of Tools According to Present Invention:
[0039] The operator installed the tools of the present invention on the same shearer and started test. The shearer parameters were set as follows: shearer haulage speed at 7.7 m/min; shearer drum speed at 28 rpm; the mining depth remained at 0.6 m. As soon as the test started, the operator noticed the machine was working under rated load. The operator thought it was the result of the sharper tool contour and high penetrating capability. So, the working parameters were set up to as follows: shearer haulage speed at 12.8 m/min; shearer drum speed at 28 rpm; the mining depth remained at 0.6 m. After the adjustment, the machine worked without any overloading.
[0040] During the test, the ancillary tips performed much better than the positive wear resistant elements in the previous tests. They actively got involved in cutting working and provided superior protection to the tool body. Few breakage of the ancillary tips occurred due to impact during their service life. No ancillary tip fell off until the shearer reached 280 m along the working face. Main tips started to drop out only after 350 m. The test lasted 4 working shift (32 hours). Totally, 52 pieces of tools had to be changed during the test, that is, 13 pieces had to be changed every working shift in average. During the test, coal production output is about 3500 T every working shift.
[0041] The following table summarizes the comparison test results:
[0000]
TABLE 1
Consumption
Consumption
per working
per ton
Maintenance
shift
of coal output
downtime
Single tipped tool
89 pcs
0.045 pcs/ton
120 min/shift
DE19821147A1 tool
69 pcs
0.033 pcs/ton
90 min/shift
CN200610102129.9 tool
55 pcs
0.023 pcs/ton
75 min/shift
Tool of present invention
13 pcs
0.004 pcs/ton
18 min/shift
[0042] As can be seen from the test result, the present invention has vastly extended the tool service lifetime. At the same time it remarkably improved efficiency of the cutting operation.
[0043] In this invention, ancillary tips can be made of hard material having a lower propensity for incendiary spark production during a cutting operation than the steel of the shank. This arrangement reduces the contact area between material to be removed and steel body, thus reducing the likelihood of producing a spark during mining or excavation operations, in particular in underground coal mining.
[0044] As described before, a wear resistant member can help to rotate the tool during its operation. But if a member fails often, using it has only a limited effect. Ancillary tips of this invention stay in position for a much longer period of time and can help to rotate the tool in operation all through its extended service lifetime.
[0045] In underground coal mining, one of the major safety problems is heavy coal dust, which can be trapped within the mine and is readily ignitable. Disadvantageously, the equipment used in coal mining can generate sparks and thus cause fires or explosion. Therefore, it is important that all appropriate steps be taken to minimize or eliminate the production of sparks. In this invention, ancillary tips can be made of hard material having a lower propensity for incendiary spark production during a cutting operation than the steel of the shank. In addition, the tapered ancillary tips can be installed above the shoulder surface, so that the coal bulk can be crashed before it comes into touch with the steel tool body. This arrangement reduce the contact area between material to be removed and steel body, thus reduced likelihood of producing a spark during mining or excavation operations, in particular in underground coal mining.
[0046] Another advantage of this invention is that the concept of ancillary tips makes it possible to realized equal-strength design of the main tip and the cutting tool body. By adjusting the configuration of the ancillary tip, including the tip contour, its length and diameter, the main tip can be held for much longer time before losing support and falling off due to wear out of the steel tool body.
[0047] The advantages of the present invention can be summarized as follows:
1. The ancillary tips are actively engaged in the cutting operation; this can not only provide better protection to the steel, but also help in reducing the cutting force. 2. The ancillary tips ensure longer and more reliable tool rotation throughout its service life. 3. The ancillary tips vastly extend service life of the tool. 4. The tools in this invention reduce likelihood of producing sparks during mining or excavation operations, and increase safety in underground coal mining. 5. The tools in this invention realize equal-strength design, which helps in making full use of the resources, especially the precious hard metals.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] FIG. 1 is a structural view of a conventional cutting tool with a plug type main tip;
[0054] FIG. 2 is a structural view of a conventional cutting tool with a mushroom type main tip;
[0055] FIG. 3 is a structural view of a conventional cutting tool with a cap type main tip;
[0056] FIG. 4 is a structural view of a conventional cutting tool with wear resistant elements;
[0057] FIGS. 5 and 6 are structural views of cutting tools installed with cone-tipped ancillary tips according to one embodiment of the present invention, wherein the ancillary cone tips raise above the steel body;
[0058] FIG. 7 is a structural views of a bit body installed with double-wedge ancillary tips according to one embodiment of the present invention, wherein the cutting edges of the ancillary tips raise above the steel body;
[0059] FIGS. 8 and 9 are structural views of a cutting tool installed with single-wedge ancillary tips according to another embodiment of the present invention;
[0060] FIG. 10 is a structural view of a cutting tool installed with single-wedge ancillary tips according to another embodiment of the present invention;
[0061] FIG. 11 is a structural view of a cutting tool installed with cone-tipped ancillary tips according to another embodiment of the present invention, wherein the ancillary cone tips raise above the steel body;
[0062] FIG. 12 is a comparison drawing showing the different protection effect between the cutting tool of the present invention and a cutting tool according to DE19821147A1 during the initial cutting stage of a cutting test;
[0063] FIG. 13 is a comparison drawing showing the different protection effect between cutting tool of the present invention and a cutting tool according to DE19821147A1 during a cutting test;
[0064] FIGS. 14-16 show other embodiments of cone-tip ancillary tips of the present invention;
[0065] FIGS. 17 and 18 illustrate other embodiments of single-wedge ancillary tips of the present invention; and
[0066] FIG. 19 illustrates another embodiments of double-wedge ancillary tips of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0067] As shown in the drawings, the cutting tools of this invention, comprise: a main carbide alloy main bit tip 1 and a bit body 2 , wherein a plurality of smaller ancillary cutting tips 3 is installed on the bit body around the main carbide alloy bit tip 1 . The sectional area of one end of the ancillary tip 3 becomes progressively smaller along its axis. The tapered profile of the tip 3 forms a plurality of cutting tips 7 or cutting edges 8 . The cutting edges 8 are provided in the form of a single-wedged cylinder or a double-wedged cylinder. In the case of cutting tool adopting cutting tips 7 , the cutting tips 7 can be positioned above the front surface 5 of the tool, so that it can be engaged in cutting operation from the very start. Similarly, in the case when a tip 3 with cutting edges 8 is used, the edges 8 can be positioned either above the front surface 5 of the tool or flush with the surface 5 . In the later case, a smoother tool profile is achieved.
[0068] In present invention, the ratio between the radius of the ancillary tips d and the length H is in the range of between 1:1.5 and 1:5. Between 3 and 50 pieces of ancillary tips 3 can be installed around the main tip 1 . For tools with plug-type main tip 1 as shown in FIGS. 5 and 7 , the buried length of the ancillary tips must be more than one third of that of the main tip. For tools with cap-type main tip 1 as shown in FIGS. 9-11 , the buried length of the ancillary tips must be more than one third of the dimension of the maximum diameter D of the main tip.
[0069] The term “buried portion”, as used herein with respect to ancillary tips, is the portion of the ancillary tip which are disposed below the external surface of the bit body (as opposed to protruding above the external surface of the bit body). The term “buried length”, as used herein with respect to ancillary tips, is a length of the buried portion of the ancillary tip.
[0070] The ancillary tips in the present invention are not simply in the form of a cylindrical or conical body. The top surface pointed to the working direction is not flat; instead, the cutting tip or the cutting edge is formed. The ancillary tips are in the shape of a cylinder with tapered tip, a dome, a cone, a wedge, a mushroom, or the like, as shown in FIGS. 14 to 19 . The ancillary tips not only act as passive wear resistant members, but also get actively involved in breaking the material to be removed.
[0071] In DE19821147A1 and CN 200610102129.9, a flat shoulder 6 of the cutting tool is necessary to accommodate the wear resistant elements. This flat shoulder can cause great resistant force against the cutting tool during its operation. This increased resistant force is harmful, as described above.
[0072] In this invention, ancillary tips can be made of a hard material having a lower propensity for incendiary spark production during a cutting operation than the steel of the shank. This arrangement reduces the contact area between material to be removed and steel body, thus reducing the likelihood of producing a spark during mining or excavation operations, particularly in underground coal mining.
[0073] In certain embodiments of the present invention, the number of the ancillary tips 3 installed on the bit body 2 around the main bit tip 1 is in the range of between 3 and 50, and optimally, in the range of between 6 and 20.
[0074] In present invention, there is provided a solution to the ratio between the radius of ancillary tips d and length H, which is in range of between 1:1.5 and 1:5, and optimally, in the range from between 1:2 and 1:4. The specific ratio can be decided according to other factors, such as the type of the main tip.
[0075] In choosing the length of the ancillary tips, following solutions are provided: (a) for tools with plug-type main tip 1 as shown in FIGS. 5 and 7 , the buried length of the ancillary tips must be more than one third of that of the main tip; in practical application, the bottom of the ancillary tips should be arranged at more or less the same level as main tip; and (b) for tools with cap-type main tip 1 as shown in FIGS. 9-11 , the buried length of the ancillary tips must be more than one third of the dimension of the maximum diameter D of the main tip. For example, if the bottom of the plug type main tip 1 is 15 mm down into the tool front surface 5 , according to this invention, the preferable length of the ancillary tips should be between about 10 mm and about 16 mm, and the diameter of the ancillary tips should be preferably about 5 mm.
[0076] In the case of a tool with a cap type main tip as shown in FIGS. 7 and 11 , the length of the ancillary tips H shall be more than ⅓ of the bottom diameter D of the main tip. More particularly, when D is 22 mm, the length of the ancillary tips should be more than 7 mm and the diameter of the ancillary tips should preferably between about 3 mm and 5.5 mm. This definition overcomes problems encountered with wear resistant element described in DE19821147A1. While DE19821147A1 did not provide a detailed illustration of the wear resistant element, it can be inferred from the provided drawings that the element is fat and short, and the main purpose thereof is to protect the square part of the tool shoulder. Nevertheless, in practical working conditions, the entire top part of the tool is often buried beneath the material to be removed. The material to be removed will wear against the thorough top part of the tool, including the metal around and beneath the bottom of the wear resistant element. In this case, the short fat wear resistant element will quickly lose the support and fall out due to wear of the surround metal. Thus, such configuration actually cannot provide lasting protection for the steel tool body.
[0077] In practical operation, the advantage of the ancillary tips are more obvious, because the tapered tip can help to break the material to be removed before it contacts the steel body, so that it further slows down the wear process. The typical wearing pattern of the cutting tool is disclosed in promotional materials of tool suppliers, all the disclosed tests are a good proof of the advantages of this invention which provides slimmer and longer ancillary tips. In one test carried out, a cutting tool of this invention is installed with a 22 mm diameter plug tip and 8 ancillary tips. The diameter of the ancillary tips is 6 mm and its length is 18 mm. The tool can still provide satisfactory service even after 15 mm of ancillary tips have been consumed. The service life was extended by 2 to 4 times. If the short fat element of prior art had been installed, it would have fallen off soon after the steel around it was worn out.
[0078] FIGS. 5-11 show a cutting tool installed with different forms of ancillary tips. The ancillary tips 3 in this invention not only resist the wear against the steel body, but their tapered front end is also actively engaged in cutting operation. The other advantage is that the tapered ancillary tips make it possible to produce the cutting tool into a very sharp shape. For example, the tapered front of the ancillary tips in FIG. 10 vastly diminishes the square shoulder of a tool, as shown in FIG. 4 , which adopts cylindrical wear resistant element. The sharpness of such a tool is essential. In practical operation in underground coal mine, the blunt front of the tool shown in FIG. 4 actually collides with the coal bulk like a hammer, as shown in the field test. The cutting effect is greatly weakened. The tool fails to penetrate into the coal bulk smoothly, instead, the hammering effect causes such heavy dust and strong vibration of the machine, that operation has to be stopped. After installing tools according to this invention to take the place of the blunt tools, the machine started to work smoothly with much higher feeding speed and lower vibrations. The improved tool of this invention can boost the working efficiency, reduce dust production, and improve the safety of the operation. In extreme cases, where penetration ability of the tool is emphasized, the shoulder of the tool can be totally removed using the concept of the present invention, as shown in FIG. 10 .
[0079] The ancillary tips in the present invention constitute an essentially different concept from the wear resistant element described in the DE19821147A1. The wear resistant elements 4 in DE19821147A1 are provided mainly in order to provide limited protection to the square part of the tool shoulder 6 . Meanwhile the notch formed during cutting can, to some extent, help in rotating the tool before it falls out. However, DE19821147A1 does not pay much attention to the side effects brought about by the extended shoulder area, which is necessary to accommodate the cylindrical element. For example, the widened shoulder part of the machine causes turbulent flow of the power and pounding vibrations.
[0080] FIGS. 14 to 16 show examples of possible embodiment of the ancillary tips 3 . The dome cutting tip 7 and cone cutting tip 7 allow the ancillary tips to get involved in the cutting operation. They are no longer passive wear resistant members. In addition, these contours get rid of the fragile square edge of simple cylindrical elements of prior art.
[0081] In FIGS. 17 to 19 , the cutting edges 8 are made from a cylindrical body by removing a portion of the top part of the element. An obtuse angle cutting edge is formed. The obtuse angle cutting edge is stronger than a right angle edge used heretofore in terms of resisting breakage under impact. At the same time, the sloped surface formed can help to eliminate the square, wide shoulder of the tool. The wedged ancillary tips 3 can be installed as shown in FIGS. 7 and 10 , with its cutting edge raised a little higher above the front surface 5 of the cutting tool. The tip can also be installed as shown in FIGS. 8 and 9 , with its slope flush with the front surface 5 of the tool so as to realize a smother profile. As shown in FIGS. 7-10 , the tools with ancillary tips are produced into much shaper contour, which will improve the penetration ability of the tool.
[0082] As mentioned above, a typical wearing pattern of the cutting tool has been described in product brochures and electronic publications of the existing tool producers. FIGS. 12 and 13 show a typical wear out pattern for a cutting tool. Specifically, for comparison, each sectional view shows a typical wear out pattern of a conventional tool in the left half and a typical wear out pattern of a tool according to this invention in the right half of the drawing. The outermost dotted line shows a profile of an unused tool. The inner solid line 9 shows a typical front contour of a heavily worn out tool before failure. A wear resistant element 4 of invention DE19821147A1 and the ancillary tips 3 of the present invention are put in position to give a clearer comparison of their actual protection effect. FIG. 12 is a comparison drawing at the initial working stage, while FIG. 13 is a drawing nearly close to the tool failure. As can be seen from the drawings, the short fat wear resistant element 4 will fall off soon after the steel on the shoulder of the tool. However, the ancillary tips 3 can stay in position for a longer period of time.
[0083] The ancillary tips 3 can be in shape of a sheet, a rectangular parallelepiped, etc. The tapered end of the ancillary tips can be in shape of a multihedral prism, a bi-conical polyhedron, etc.
[0084] This invention is not to be limited to the specific embodiments disclosed herein and modifications for various applications and other embodiments are intended to be included within the scope of the appended claims. While this invention has been described in connection with particular examples thereof, the true scope of the invention should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification, and following claims.
[0085] All publications and patent applications mentioned in this specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication or patent application mentioned in this specification was specifically and individually indicated to be incorporated by reference. | A cutting tool for breaking or excavating machines, comprising: a tool body,a main tip ( 1 ), and a plurality of ancillary tips ( 3 ), wherein the ancillary tips ( 3 ) comprises a plurality of tapered cutting tips ( 7 ) or a plurality of cutting edges ( 8 ) for breaking operation; and the ancillary tips ( 3 ) are disposed on the tool body ( 2 ) around the main bit tip ( 1 ). The cutting tool for breaking or excavating machines of the invention is capable of increasing and elongating the wear resistance capability without sacrifice its penetrating ability so as to extend the service life of the bit, as well as increase its working efficiency and safety. | 4 |
TECHNICAL FIELD
The present invention relates to oral compositions in the form of microcapsules which reduce oral bacteria and provide long lasting breath protection.
BACKGROUND OF THE INVENTION
The use of breath control compositions such as breath mints, mouthwashes, chewing gums, etc. is widespread in most of the developed countries of the world. Another form which has been used are microcapsules containing a flavorant or other breath protection agent. These executions have acceptance due not only to their usefulness away from a place to expectorate mouthwashes but also due to the fact that they can be swallowed when the user does not need any more of the actives or doesn't want the microcapsule in the mouth any longer.
Although microcapsules have been used, there are problems associated with incorporating certain breath protection agents/antimicrobials into the core. Oftentimes the wall of the microcapsule may develop imperfections and cause loss of the contents prematurely. Additionally, the actives may not be easily solubilized in the materials usually present in the core.
The prior art discloses a variety of means for providing breath protection and reducing oral bacteria. Included among such means are sprays disclosed in U.S. Pat. No. 3,431,208, Mar. 4, 1969 to Bailey. Particles containing an adhesive member are disclosed in U.S. Pat. No. 3,911,099, Oct. 7, 1975 to Den Foney et al. Another form is a mouthwash concentrate in a unit dosage cup as disclosed in U.S. Pat. No. 4,312,889, Jan. 26, 1982 to Melsheimer. Breath protection microcapsules are disclosed in U.S. patent application Ser. No. 08/003,080 to Stapler et al., filed Jan. 11, 1993, now U.S. Pat. No. 5,300,305 issued Apr. 5, 1994 and U.S. patent application Ser. No. 08/017,944 to Stapler et al., filed Feb. 12, 1993, now U.S. Pat. No. 5,286,496 issued Feb. 15, 1994. All of these references are incorporated herein by reference.
The present inventors have found that by incorporating the breath control/antimicrobial actives into the core of the microcapsule along with organic diluents and a specific sweetener combination, problems associated with other microcapsule executions can be avoided.
The volume limitations inherent in the use of the microcapsules of the present invention requires careful selection of the amount and type of materials contained therein. Without being limited by theory, it has been discovered that the use of a specific sweetener component in the present invention provides increased actual and/or perceived sweetness as well as improving the sweetness perception in the oral cavity. This combination of certain specific sweeteners provides an optimized sweetness profile and/or sweetness intensity in the microcapsules of the present invention.
It is therefore an object of the present invention to provide improved microcapsules.
It is another object of the present invention to provide microcapsules which provide improved breath control and reduce oral bacteria having an improved sweetness profile.
It is still another object of the present invention to provide improved methods of providing breath control and reducing oral bacteria.
These and other objects will become more apparent from the detailed description which follows.
SUMMARY OF THE INVENTION
The present invention in one of its aspects relates to improved microcapsules which contain a sweetener component and breath control actives/antimicrobials in the core of the microcapsule along with an organic diluent and, optionally, in the shell of the microcapsule.
All percentages and ratios used herein are by weight unless otherwise specified. Additionally, all measurements are made at 25° C. unless otherwise specified.
DETAILED DESCRIPTION OF THE INVENTION
The essential as well as optional components of the capsules of the present invention are described in the following paragraphs.
Capsule Shell Material
The shell material of the microcapsules of the present invention can be any materials which are suitable for ingestion as well as retention in the oral cavity. Materials which are suitable include gelatin, polyvinyl alcohols, waxes, gums, sucrose esters and sugar candy type materials used in cough drops and mints, for example.
The shell material is used to form any of a wide variety of shapes such as spheres, oblong shapes, disks, puffed squares and cylinders. The shell thickness is preferably in the range of about 30 um to about 2 mm, preferably from about 70 um to about 150 um. If the microcapsules are spherical, the particle diameter is generally in the range of from about 2 mm to about 9 mm, preferably from about 3 mm to about 7 mm.
Breath Control Agents/Antimicrobials Present in the Core and in the Shell Material
The breath control agents used in the cores of the microcapsules include quaternary ammonium salts such as pyridinium salts (e.g., cetyl pyridinium chloride), domiphen bromide, other cationic materials such as chlorhexidine salts, zinc salts and copper salts. Other organic agents such as triclosan and other noncationic water insoluble agents are also useful herein. Such materials are disclosed in U.S. Pat. No. 5,043,154, Aug. 27, 1991, incorporated by reference herein.
These breath control/antimicrobial agents are used in an amount of from about 0.001% to about 2%, preferably from about 0.005% to about 1% of the total core contents.
Dispersed within the shell material may be the same agents at the same concentrations.
Diluents for Use in Microcapsule Core
The solubilizing agent for the breath control/antimicrobial agents used in the cores of the present microcapsules can be any of a number of materials. Preferred are oils such as corn, olive, rape-seed, sesame, peanut or sunflower. Other preferred materials are triglycerides such as Captex 300 and polyethylene glycols such as PEG 400. These are used in an amount of from about 20% to about 80%, preferably from about 35% to about 70% of the total capsule weight.
Sweetener Component
The sweetener component of the present invention is a sweetener mixture having an improved sweetness intensity and/or profile comprising:
(a) acetosulfame and
(b) a second artificial sweetener selected from the class of the aspartyl peptide esters, the sulfamate sweeteners, the sulfimide sweeteners, the dihydrochalcone sweeteners and the ammoniated glycyrrhizins and mixtures thereof.
These sweetener combinations are more fully described in U.S. Pat. No. 4,158,068 to Von Rymon Lipinski et al., issued Jun. 12, 1979, incorporated by reference herein.
Acetosulfame is a potassium salt. In principle it could be replaced by other non-toxic water-soluble salts, especially the sodium and calcium salt of 3,4-dihydro-6-methyl-1,2,3-oxathiazine-4-one-2,2-dioxide, but these salts do not bring about any advantages in comparison with the potassium salt.
The most important representatives of the second (b) sweetener classes are mainly the aspartyl phenyl alanine methyl ester (an aspartyl dipeptide ester) and the non-toxic water-soluble salts, especially the sodium and calcium salt, of cyclohexyl sulfamic acid (sulfamate sweeteners), saccharin and its non-toxic water-soluble salts, especially saccharin-Na (sulfimide sweeteners), the neohesperidin and naringine dihydrochalcones (dihydrochalcone sweeteners) and the ammoniated glycyrrhizins, especially monoammononium glycyrrhizin. One or more of these sweetener types may be mixed with acetosulfame.
The components of the mixture (a) and (b) can be mixed in any possible ratio; however, they are preferably mixed in a ratio inverse to their sweetening powers. The sweetening powers are generally determined in comparison with saccharose, for example, in the manner described in the journal "Chemie in unserer Zeit", pages 142-145 (1975). The following weight ratios of the sweetener components have found to be advantageous:
acetosulfame/aspartyl phenyl alanine methyl ester in a ratio of 1:10 to 10:1, especially of about 3:1 to 1:2.
acetosulfame/sodium cyclamate in a ratio of about 3:1 to 1:12, especially of about 1:2 to 1:12.
acetosulfame/saccharin-Na in a ratio of about 1:2 to 10:1, especially of about 1:1 to 8:1, preferably 1:1 to 3:1.
acetosulfame/neohesperidin-dihydrochalcone in a ratio of about 5:1 to 20:1, especially of about 8:1 to 25:1.
Preferred for use in the microcapsule core is a sweetener component comprising acetosulfame/saccharin-Na/aspartyl phenyl alanine methyl ester and more preferably further comprising monoammononium glycyrrhizin.
Also useful in either the core or shell of the microcapsules are additional sweeteners such as caloric sweeteners, e.g., sucrose, d-fructose and d-xylose, the amino acid sweeteners such as glycine as well as the glycosides such as stevioside.
While the sweetener component of the present invention is generally contained in the core of the microcapsule, it can be contained in the shell and preferably is in both the core and the shell of the microcapsule. Most preferred for use in the microcapsule shell is a mixture of acetosulfame/saccharin-Na/aspartyl phenyl alanine methyl ester, especially in a ratio of about 28:6:1. Without being limited by theory, it is believed that the use of the high potency sweetener component of the present invention in the shell provides an immediate sweet taste when the microcapsule enters the oral cavity, thereby improving the sweetness profile and sweetness perception as well as overall taste perception (including taste coverage) of the microcapsule.
Additional Agents Suitable for Use in the Core of Capsule
The core of the microcapsules of this invention may contain any number of additional materials to provide additional efficacy and/or sensory perceptions. Such agents may include flavoring agents such as thymol, eucalyptol, menthol, methyl salicylate or witch hazel. These agents are used in an amount of from about 0.1% to about 25%, preferably from about 5% to about 15% of the total capsule weight.
In addition, a variety of sweetening agents such as sugars, corn syrups, saccharin or aspartame may also be included in the core. These agents are used in an amount of from about 0.1% to about 5%, preferably from about 0.35% to about 1.5% of the total capsule weight.
Method of Manufacture:
The capsules of the present invention can be made using a variety of techniques. One method is described after the following examples.
Industrial Applicability:
The capsules of the present invention are used by placing the capsules into the mouth and retaining them therein for a period sufficient to provide the desired effect.
The following examples further describe and demonstrate preferred embodiments within the scope of the present invention. The examples are given solely for the purposes of illustration and are not to be construed as illustrative of limitations of this invention. Many variations thereof are possible without departing from the invention's spirit and scope.
EXAMPLES 1-5
The following compositions/capsules are representative of the present invention.
______________________________________ Weight %Component 1 2 3 4 5______________________________________Gelatin 9.840 10.206 8.345 9.332 9.345Sorbitol Solution 3.616 4.718 -- 2.941 2.560(70% Aqueous, Ex.1-2; Crystalline,Ex. 4-5)Saccharin 0.418 0.423 0.542 0.460 0.548Acetosulfame 0.695 0.702 1.626 0.779 1.321Aspartyl phenyl 0.495 0.500 -- 0.577 0.397alanine methyl esterMonoammononium 0.027 0.300 -- 0.027 0.040glycyrrhizinNeohesperidin 0.020 0.020 -- -- --dihydrochalconeFD&C Blue #1 0.010 0.010 0.020 0.015 0.015FD&C Yellow #5 0.005 0.005 -- -- --Captex 300.sup.1 8.352 8.453 71.925 69.260 8.448Flavor 7.158 7.240 7.247 12.112 7.239Citric Acid -- -- -- 0.259 --Cetyl Pyridinium.sup.2 0.675 -- -- -- 0.135chlorideDomiphen Bromide 0.075 -- -- -- 0.015Propylene Glycol 2.017 -- 3.025 -- 2.040Glycerin 0.270 -- 4.385 0.273 0.404Chlorhexidine -- 0.120 -- -- --ZnCl.sub.2 -- -- 0.025 -- --Sodium Lauryl Sulfate -- -- 0.300 -- --Triclosan -- -- -- 0.280 --Polyethylene glycol 29.522 31.900 -- -- 29.703400Sucrose Acetate 33.408 33.785 -- -- 33.790IsobutyrateWater 3.397 1.618 2.560 3.685 4.000______________________________________ .sup.1 Captex 300 is a triglyceride supplied by Capitol City Product, Columbus, Ohio. .sup.2 This amount includes that in the gelatin shell as well as in the core.
The above compositions are prepared by mixing the components of the core in one container and the components of the shell(s) in another container. The shell(s) materials are heated to provide a fluid medium. The core and shell(s) materials are then pumped separately to a two or three fluid nozzle submerged in an organic carrier medium. The capsules formed are allowed to cool and stiffen. They are then dried and separated for further handling.
In the above compositions any of a wide variety of other shell materials, breath control agents, sweeteners as well as other components may be used in place of or in combination with the components listed above. These are listed on pages 2 through 5. | The present invention relates to oral compositions in the form of microcapsules which reduce oral bacteria and provide long lasting breath protection. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to the tanning of animal hides and in particular to the more efficient utilization of chromium tanning compositions.
This application is related to the following copending applications: Ser. No. 052,149, filed June 26, 1979, now U.S. Pat. No. 4,285,689, in the name of Marcel Siegler, entitled "Leather Tanning Composition and Method"; and Ser. No. 052,217, filed June 26, 1979, now U.S. Pat. No. 4,270,912, in the name of William C. Prentiss, entitled "Stabilized Tanning Composition and Method."
Chromium compositions are universally employed as primary tanning agents in the manufacture of leather from animal hides. A typical chromium composition (popularly known as and hereinafter abbreviated to "chrome tan" or "chrome") is a chromium salt solution prepared by reducing sodium bichromate with a sugar or a sugarlike reagent and sulfuric acid. The resulting chrome tan is a basic chromium sulfate, Cr(OH)SO 4 , having chromium in the trivalent state and having about 25-60% basicity, more usually about 33-40% basicity. Chrome tans have numerous advantages over other tanning agents such as vegetable extracts, synthetic tanning agents (such as phenolic resins) similar in tanning action to vegetable extracts, aldehydes such as formaldehyde and glutaraldehyde, and other mineral tanning agents such as aluminum, iron, titanium and zirconium salts. These advantages include production of a leather more resistant to collagen denaturation and greater control over the tanning process. Chromium salts are also sometimes used in secondary tanning treatments, such as pretanning and retanning (see U.S. Pat. No. 3,888,625), although it is more common to use other tanning agents for such purposes.
The complete tanning process generally comprises both wet and dry operations. The major steps of the wet operations are unhairing (including liming), bating (removal of unhairing chemicals and non-leather making substances), pickling (acidification to maintain the subsequently added chrome tan soluble and addition of brine to prevent acid swelling), and chrome tanning. Secondary wet operations often following the chrome tanning include wringing, splitting and shaving, retanning, coloring, fatliquoring, and setting out. Dry operations follow the wet operations and include drying, conditioning, staking, buffing, finishing, plating, measuring and grading. These and other leather processing technique are thoroughly described in the literature, as in "Leather Facts," New England Tanners Club, Peabody, Mass. (1965).
In chrome tanning, it is known that the chromium may be complexed or "masked" with an organic acid such as formic or acetic acid to increase the pH at which hydrated chromium oxide begins to precipitate from the basic chromium sulfate to above the pH at which the carboxyl groups of the hide collagen begin to ionize and become more receptive to attachment of the chrome complex. Thus, it is known that chrome tanning should begin at a fairly low pH (for example, below about 3.0) to permit the rapid penetration of chrome through the pickled hide, and the tanning should be finished at a higher pH such that the chrome can combine with the collagen and form hydrated chromium oxide-sulfate cross-linked microstructures which provide the stabilized condition in the hide known as "tanning." Formate-masked chrome generally requires a pH of about 3.75 to release the chrome while acetate-masked chrome requires a pH of about 4.25. The pH adjustment, however, should be short of that which will cause precipitation of hydrated chrome oxide since the latter does not play a part in the tanning process and can lead to poor tanning and undesirable side effects.
While there are many variations on chrome tanning, for the purpose of shortening process time, increasing rate of chrome penetration and improving chrome utilization, the variations are for the most part based on pH and temperature control, masking of the chrome, and concentration of chrome in the tanning liquor ("float"). The latter is usually controlled by adding or subtracting water during the tanning process.
Usually, the amount of chrome tan charged is about 1.5% to about 2.0% calculated as Cr 2 O 3 , based on "white weight" (weight of water-swollen hide stock after unhairing and liming but before bating). At the end of tanning, the chrome left over in the tanning liquor usually varies from about 6.0 to about 12.0 g./l. chrome tan as Cr 2 O 3 as determined by American Leather Chemists Association ("ALCA") Test Method C-1. This exhaust liquor contains chrome in the form of a highly masked, soluble, hydrated, chromium oxide-sulfate complex, and is probably more anionic then cationic in character. At equilibrium about 2.5 to 4.0% chrome tan as Cr 2 O 3 commonly is fixed in the hide stock on a moisture free basis, as determined by ALCA test method D-10. However, this amounts to only about two-thirds of the chrome being utilized, the balance being discarded in the exhaust liquor.
Although chrome in the trivalent state is nowhere as toxic as hexavalent chrome, it is considered hazardous by regulatory agencies when found in effluent streams. Reducing the amount of chrome in the effluent by increasing the amount of chrome fixed in the hides, that is, improving the efficiency of chrome utilization in chrome tanning, has been the subject of many proposals in recent years. Among the anti-pollution measures practiced may be mentioned re-use of exhaust chrome liquors in pickling and/or tanning, and precipitation of the chrome followed by redissolving and reuse. It is estimated that only about 60% of the chrome in the effluent is recovered for re-use by these procedures, since it is difficult to recover all of the chrome liquor remaining from the tanning step and subsequent processing. Accordingly, recent antipollution measures have concentrated on reducing chrome in the exhaust liquor by improving chrome utilization during the tanning.
A number of chemical methods have been developed to improve the efficiency of chrome utilization. One such method is the use of sparingly soluble neutralizing agents for the acidified chrome tanning bath, such as magnesium oxide and calcium carbonate, rather than readily soluble sodium bicarbonate. By gradually increasing the pH of the float through slow solubilization, and thereby gradually increasing the basicity of the chrome, more chrome is utilized in the tanning process (by avoiding the normal levels of precipitation) than would be the case with rapidly soluble salts. Considerable care is required with these neutralizing agents, however, because with temperature changes, solubility of the neutralizing agent changes and resultant precipitation of chrome within the stock may occur, leading to spots in the leather. Nevertheless, at the higher pH achievable by this technique, the chrome in the exhaust liquor can be reduced to less than one g./l. Cr 2 O 3 by reducing the chrome charge to 80% of normal. A variation on this process is disclosed in U.S. Pat. No. 3,888,625 wherein exhaust liquor is neutralized by reaction with a sulfite salt and an aldehyde or aldehyde-generating compounds (such as certain oxazolidines).
It is also known to use sparingly soluble dicarboxylic acids, such as adipic or phthalic, as masking agents to increase chrome exhaustion. More soluble acids, such as oxalic, malonic and maleic, are also known to reduce chrome exhaustion. However, it is difficult to achieve uniform penetration of the chrome tan through full thickness hides when using these techniques. The coordination of chrome with alkaline materials such as triethanolamine is also useful for the dechroming of scrap leather. See R. M. Lollar, JALCA, 35, (10) 584(1940).
Another known effort to improve efficient use of chrome is the use of aminocarboxylic chelating agents such as ethylenediaminetetraacetic acid or salts thereof, as in West German Pat. No. 1,257,352 granted July 18, 1968. In this approach a preformed chrome tan chelate is prepared with the chelating agent at a low pH where it is stable. The chelate is then applied to limed hide stock or hide stock washed out of bate and still alkaline, at which pH the chrome chelate becomes unstable and tanning takes place with the formation of the calcium chelate reaction product (from lime still in the bated stock). Because of the resultant high pH, there will be less chrome in the exhaust liquor. However, again because of the high pH, it is difficult to achieve good penetration and uniform distribution of the chrome tan in the hide.
Because of the multiplicity of steps and complexity of the total leather manufacturing process, the tanning industry is reluctant to make any significant change in a key step, such as the chrome tanning step, in view of the possibility that such change will upset their long established control over the other steps and therefore the quality of the leather. Accordingly, it has been the tendency in the industry to recycle or precipitate effluent chrome rather than to make changes in the chrome tanning step. Precipitation and recycling of course, substantially add to the complexity and cost of the total process. The industry most likely, therefore, would find acceptable an improvement which would reduce chrome in the effluent so long as no significant changes are required in the chrome treatment step and the quality of the leather is not lessened.
SUMMARY OF THE INVENTION
It has now been found that a chrome tan can be utilized more efficiently in the tanning of animal hides, thereby reducing the amount of chrome required in the charge and found in the exhaust liquor, by providing in the acidified medium containing the hide stock and chrome tan, after unhairing and bating, a water soluble amino compound. The amino compound is one which per se has substantially no tanning properties but which is capable of enhancing the tanning afforded by a chrome tan. By this means not only may the amount of chrome tan charged for effective tanning be decreased with consequent lower chrome in the exhaust, but also no substantial changes are required in the conventional tanning process and the noxious conditions resulting from the use of aldehydes or the generation of aldehydes by pretanning agents or auxiliaries are avoided.
DETAILED DESCRIPTION
The amino compounds useful in this invention are those non-toxic, water soluble, amino functionality containing compounds which provide no substantial tanning action when used alone but which augment the tanning action of chrome tanning agents. For the purpose of this invention, "water soluble" includes "water solubilizable," that is, the capability of becoming water soluble upon the addition of solubilizing agents such as surfactants, emulsifiers and the like. Excluded from the amino compounds of the invention are the amino compound tanning agents of the above-identified copending patent applications Ser. Nos. 052,149 and 052,150. The latter applications cover certain amino compounds preferably used as non-chrome pretanning agents and probably tan by the generation of an aldehyde, as indicated by an aldehyde odor. The present invention thus avoids the possibility of discomfort or toxic effects due to aldehyde.
The amino compounds of the present invention include a variety of compounds containing amino functionality, both polymeric and nonpolymeric. The nonpolymeric amino compounds generally are aliphatic, including cycloaliphatic, compounds such as primary, secondary and tertiary mono- and polyamines, and salts thereof, such as salts formed with mineral acids such as sulfuric and hydrochloric acid, and organic (mono- and polycarboxylic) acids such as acetic, formic and phthalic acid. The amines may also carry other functional groups which contribute to the water solubility, such as hydroxyl and/or carboxyl groups. Accordingly, the amines include alkylamines, alkanolamines, and aminocarboxylic acids and aminopolycarboxylic acids, in each case both aliphatic and cycloaliphatic.
The aminopolycarboxylic acids include those of the formula: ##STR1## wherein R is: ##STR2## wherein n is 1 or 2, A is a low molecular weight aliphatic or cycloaliphatic moiety, particularly a 1,2-cyclohexylene moiety or a moiety of the formula ##STR3## wherein m and p are either 2 or 3, and q is 0, 1 or 2. Examples of the foregoing aminopolycarboxylic acids are nitrilotriacetic acid, nitrilotripropionic acid, ethylenediaminotriacetic acid, ethylenediaminotetraacetic acid, propylenediaminotetraacetic acid, ethylenediaminotetrapropionic acid, diethylenetriaminotetra- or pentaacetic acid, and 1,2-cyclohexylenediaminotetraacetic acid.
Aminopolycarboxylic acids of the foregoing types are described in West German Pat. No. 1,257,352 published July 18, 1968. The mineral acid or organic acid salts of the foregoing aminocarboxylic acids are also useful in accordance with the present invention.
Specific alkyl amines and alkanolamines useful in the present invention are primary amines such as 2-amino-2-methylpropanol-1, t-butylethanolamine and 2[2-ethylamino]ethanol; secondary amines, such as N-methylethanol amine and diethanol amine; tertiary amines, such as triethyl amine and triethanol amine; alkylenepolyamines such as ethylene diamine, diethylenetriamine, triethylenepentamine and the like; and condensates of alkylamines with an alkylene oxide such as ethylene oxide, such as compounds of the formula t--RNH (CH 2 CH 2 O) x H wherein R is mixed alkyl containing about 12 to 24 carbon atoms and x is in the range of about 1 to 30. Typical of such condensates are t--C 12-14 NH (CH 2 CH 2 O) y H, wherein y varies from about 1 to 15 and t--C 18-22 NH (CH 2 CH 2 O) 25 , such series being commercially available under the trademarks "Triton RW" and "Priminox T," respectively. A similar condensate is the amino compound sold under the trademark "Jeffamine D-400" and described as the bis-2-aminopropyl ether of an ethoxy diol wherein the diol has a molecular weight of about 400.
Preferred amino compounds are those which are water soluble without the addition of solubilizing agents, which are essentially odorless, and which remain stable over the pH range of the chrome tanning step, from an acid pH when the pickled hide stock is first contacted with the chrome tan to the neutral or slightly alkaline pH during chrome fixation.
No substantial deviation is required from normal tanning operations when practicing the present invention. The amino compound can be added neat or in aqueous solution, in either free amine form or after neutralization with a mineral or organic acid, to the aqueous medium containing an acidified hide stock, or to the hide stock prior to or simultaneously with acidification or after acidification but prior to addition of the chrome tan, or simultaneously with addition of the chrome tan to the acidified hide stock. Thus, as a general rule, the amino compound is provided in the acidified medium which contains or will contain the chrome tan, so that it operates as an assist or auxiliary to the chrome tan. Preferably, the amino compound is added to the aqueous medium containing the hide stock after acidification but before addition of the chrome.
Conventionally, the acidified chrome tan hide stock solution will have a pH in the range of about 1.5 to 4.5, preferably about 1.8 to 2.5. From about 0.01 wt. % to about 5.0 wt. % of the amino compound based on white weight may be used but optimum amounts will depend upon the amount of chrome tan and other variables and may be determined by routine trial. In accordance with preferred embodiments of the invention, only about 1.0 wt. % to about 1.25 wt. % (on white weight) of chrome tan calculated as Cr 2 O 3 is required in the charge to the hide stock, when about 0.1 wt. % to about 2.0 wt. % (on white weight) of amino compound also is present, as compared to 1.5% or more chrome tan when no amino compound is added. Accordingly, without the amino compound, higher amounts of chrome tan would be required for equivalent tanning, and the discharge would have a substantially higher chrome content.
Among some specific variations on utilizing the amino compounds in accordance with the invention are the following alternative sequences. In each sequence a hide stock in an aqueous medium is bated, washed out of bate and acidified according to standard practice. The float is then adjusted to the desired level and the chrome tanning process commenced. Also, in each sequence, the acidification is a "pickle," in that brine is added before the pH adjustment in order to prevent acid swelling of the hides. The invention can be practiced without brine addition, however. Moreover, the reagents may be added sequentially, alternating with drumming, or premixed and added as a composite.
1. Add amine, drum (i.e. agitate in a revolving drum), add salt (NaCl), drum, add sulfuric acid to pickle, drum, add sodium formate and basic chrome sulfate, drum, and neutralize.
2. Add salt, drum, add sulfuric acid, drum, add amine, drum, add sodium formate and basic chrome sulfate, drum, and neutralize.
3. Add salt, drum, add formic acid, drum, add amine, drum, add sulfuric acid, drum, add basic chrome sulfate, drum, and neutralize.
4. Add salt, drum, add sodium formate and sulfuric acid, drum, add amine, drum, add basic chrome, drum, and neutralize.
5. Add salt, drum, add sulfuric acid, drum, add amine, sodium formate and basic chrome sulfate, drum, and neutralize.
The following Table I summarizes typical ranges, in wt. % based on white weight, for concentrations of active ingredients in practicing the present invention on full thickness hides. While these ranges represent the more usual commercial practice, it will be understood that amounts outside these ranges will be effective, since the tanning process involves multiple variables, including the type of chrome tan and amino compound, pH, temperature, duration of agitation of stock, other additives in the solution, and hide thickness.
TABLE I______________________________________Typical Ranges Min. Max Preferred______________________________________Float 10% 150% 40%-50%Amino compound 0.1% 2.0% 0.2%-0.4%Salt (NaCl) 3° Be 10° Be 4-7° BeH.sub.2 SO.sub.4 (95%) 1% 2% 1.25%-1.75%Sodium formate 0.0% 2% 0.5%-1.25%Basic chrome sulfate,as Cr.sub.2 O.sub.3 1.0% 1.5% 1.2%-1.3%Sodium bicarbonateas needed to neutralize______________________________________
While the mechanism by which the present invention operates is not known, it is believed that since chrome tanning depends upon reaction of the chrome with available carboxyl groups in the collagen of the hide stock, the amino compound probably blocks this reaction temporarily so that the chrome will more readily penetrate into the stock before combining. Blocking action is reversible, depending upon amino compound concentration and pH.
The invention is applicable to the chrome tanning of animal hides of all types, including bovine, ovine and marsupial, such as cattle, sheep, pigs, goats and reptiles. For the purposes of this specification, "hides" includes full thickness animal pelts as well as skins. The invention is especially beneficial for the chrome tanning of full thickness hides because it aids in overcoming the difficulty of penetration and exhaustion of chrome, but it is also applicable to the tanning of light weight stock such as lime split hides. The invention may also be practiced in conjunction with various other leather manufacturing processes known in the art. For example, the invention may be practiced in pretanning and with mixed tannages, such as one or more of a vegetable, synthetic, aldehydic or other mineral tan, in admixture or in combination with a chrome tan.
The following examples wherein all parts and percentages are by weight unless otherwise specified, are intended as further illustration of the invention without necessarily limiting the scope thereof. Among the benefits shown by the examples is that whereas a standard, masked chrome tanage utilizes only about 60% of the chrome tan charged (as Cr 2 O 3 ), the balance being discharged to a waste stream, the present invention improves the chrome tan utilization to about 90% so that the chrome tan charged can be reduced by 20 to 25%. The chrome content of the discharge is therefore significantly reduced so that treatment to recover and/or recycle the chrome is easier and uncontrolled loss to a waste stream is reduced. Moreover, since a leather product produced in accordance with the invention will contain the normal chrome content with minimal content of amino compound, the susceptibility of the leather to retanning and subsequent processing will be changed minimally or not at all.
EXAMPLE 1
1000 g. of limed cowhide stock was delimed and bated using a conventional procedure. The delimed and bated stock was washed for 10 minutes and floated in 1000 cc. of 3% sodium chloride solution. The stock was drummed for 10 minutes and then 7.5 g. formic acid (diluted 1 to 5 with water) was added, followed by a 30 minute drumming. The solution and the stock had a pH of 4.8 and 6-6.25, respectively. To the mixture was added 10 g. of an aqueous diethanolamine sulfate solution (30% diethanolamine, "DEA"), followed by drumming for two hours. At the end of the run, the pH of the bath was lowered by adding 2.5 g. sulfuric acid. The stock was drummed for 10 minutes and the solution had a pH of 3.8. 12.5 g. (1.25% on white weight) Cr 2 O 3 (50% solution of basic chromium sulfate, sold under the trademark "Koreon M") was added and the mixture drummed for 21/2 hours. The final pH's of the solution and the stock were 3.9 and 4-4.25, respectively. The blue stock stood a one minute boil without shrinking thus indicating full tanning. The Cr 2 O 3 in the spent liquor was 2.4 g./l.
EXAMPLE 2
1000 g. of limed cowhide stock was delimed and bated using a conventional procedure. The bated stock was washed for 10 minutes and floated in 1000 cc. of 5% sodium chloride solution. The stock was drummed for 10 minutes and then 20 g. sulfuric acid (diluted 1 to 10 with water) was added followed by a 2 hr. drumming. The stock was left standing overnight in the liquor. By next morning the solution and the stock had a pH of 2.2 and 2.25-2.50, respectively. To the liquor containing the stock was added 10 g. of an aqueous diethanolamine sulfate solution (30% DEA), followed by drumming for 30 minutes. At the end of the run 10 g. sodium formate (dry) was added, followed by drumming for 30 minutes. 12.5 g. (1.25% on white weight) Cr 2 O 3 (Koreon M in the form of 50% solution) was added and the mixture drummed for 30 minutes. The stock was checked for complete penetration of chrome and then neutralized with sodium bicarbonate (10% solution) to a liquor pH of 3.7-3.8 and a stock pH of 4-4.25. The total run in chrome liquor was 21/2 hrs. The blue stock stood a one minute boil. The Cr 2 O 3 in spent liquor was 1.2 g./l. as compared with 4.2 g./l. under essentially the same conditions but without the diethanolamine sulfate.
EXAMPLE 3
1000 g. of limed cowhide stock was delimed and bated using a conventional procedure. The delimed and bated stock was washed and floated in a 1000 ml. of 3% sodium chloride solution. The stock was drummed for 10 minutes and then 30 g. glacial acetic acid (diluted 1 to 5 with water) was added, followed by a three hour drumming. The stock was let stand overnight in the pickle liquor. The solution and the stock had a pH of 4.5 and 5-5.25, respectively. To this mixture was added 10 g. of a 30% aqueous diethanolamine sulfate solution, followed by drumming for two hrs. At the end of the run 12.5 g. (1.25% on white weight) Cr 2 O 3 (Koreon M in the form of 50% solution) was added and the mixture drummed for 21/2 hrs. The pH of the solution was 4.2 with a stock pH of 4-41/2. The blue stock stood a one minute boil. The Cr 2 O 3 in spent liquor was 3.3 g./l.
EXAMPLE 4
Comparative
Example 2 was repeated in all essential respects except for the absence of the diethanolamine sulfate solution and the presence of 1.5% Cr 2 O 3 . This is the level of Cr 2 O 3 in conventional chrome tanning. The Cr 2 O 3 in the spent liquor was 5.4 g./l. The stock stood a one minute boil.
EXAMPLE 5
Table II below shows the effect of concentration of diethanolamine sulfate solution (30% DEA) or as diethanolamine (DEA) on the amount of chrome (as Cr 2 O 3 ) remaining in the spent chrome tan liquor in a tanning procedure essentially as described in Example 2. It will be noted that although the chrome in the effluent was reduced from 4.2 g./l. to 1.6 g./l., at the lowest diethanolamine sulfate concentration tested (0.1% DEA), the leather did not stand the boil. Therefore, the minimum concentration of this amino compound for optimum results is about 0.2% as DEA on white weight or some concentration between about 0.2% and 0.1%. There was a substantial reduction in the chrome in the effluent in all cases, nevertheless.
TABLE II______________________________________% Diethanolamine Cr.sub.2 O.sub.3 Withstoodsulfate solution Cr.sub.2 O.sub.3 discharge boil one(30%), (as % DEA) charge % g./l. minute______________________________________0.33 (0.1) 1.25 1.6 no 0.66 (0.198) 1.25 1.5 yes1.70 (0.51) 1.25 2.0 yes2.50 (0.75) 1.25 2.5 yes3.30 (0.99) 1.25 2.6 yescontrol (0.00) 1.25 4.2 yes______________________________________
EXAMPLES 6-17
Table III below summarizes test results for various amino compounds using a chrome tanning procedure essentially as described in Example 2. From these test results it can be seen that the Cr 2 O 3 charge can be reduced from 1.5% to 1.25% or less when the amino compound is present.
______________________________________Amino compound Cr.sub.2 O.sub.3 withstand% (as free amine) Cr.sub.2 O.sub.3 discharge boilEx. on white weight charge, % g./l. 1 minute______________________________________6. 2-amino-2-methyl 1.25 1.5 yespropanol-1, 1%7. triethylamine, 1% 1.25 2.0 yes8. N-methylethanolamine 1.25 3.0 yes1%9. triethanolamine, 0.3% 1.25 1.6 yes10. 2[2-ethylamino]ethanol, 1.25 3.3 yes0.3%11. bis-2-aminopropyl.sup.1 1.25 3.9 yespolyethoxyethanol, 0.3%12. t-C.sub.12-14 aminoethanol.sup.2, 1.25 3.3 yes0.3%13. diethylenetriamine, 1.25 3.0 yes0.3%14. t-butylethanolamine, 1.25 2.3 yes0.3%15. diethanolamine lauryl 1.25 3.3 yessulfate.sup.3 0.30%16. sodium ethylene diamino 1.25 3.4 yestetraacetate, 0.02%17. sodium ethylene diamino 1.25 2.0 yestetraacetate, 0.2%control - none - 1.25 4.2 yescontrol - none - 1.5 5.4 yes______________________________________ .sup.1 Jeffamine D400, Jefferson Chemical Company .sup.2 Triton RW10, Rohm and Haas Company .sup.3 Standapol, Henkel Chemicals Corp.
EXAMPLE 18
1000 g. of limed cowhide was delimed and bated using a conventional procedure. The bated stock was washed for 10 minutes and floated in 1000 cc. of 5% sodium chloride solution. The stock was drummed for 10 minutes and then 20 g. of sulfuric acid (diluted 1 to 10 with water) was added followed by a 2 hr. drumming. The stock was left standing overnight in the liquor. By next morning the solution and the stock had a pH of 2.5 and 2.5-2.75, respectively. To the liquor containing the stock was added 10 g. of an aqueous diethanolamine sulfate solution 30% DEA). The addition was followed by drumming for 30 minutes. At the end of the run 10 g. of sodium formate was added (as a 10% aqueous solution) immediately followed by addition of 12.5 g. (1.25% on white weight) Cr 2 O 3 (Koreon M in the form of 50% solution). The mixture was then drummed for 30 minutes. The stock was checked for complete penetration of chrome and then neutralized with sodium bicarbonate (10% solution) to a liquor pH of 3.9 and a stock of 4.0-4.25. The total run in the chrome liquor was 21/2 hours. The resulting blue stock stood a one minute boil. The Cr 2 O 3 in the spent liquor was 1.4 g./l.
EXAMPLE 19
1000 g. of limed cowhide stock was delimed and bated using a conventional procedure. The bated stock was washed for 10 minutes and floated in 1000 cc. of 5% sodium chloride solution. The stock was drummed for 10 minutes and then 20 g. of sulfuric acid (diluted 1 to 10 with water) was added followed by a 2 hr. drumming. The stock was left standing overnight in the liquor. By next morning the solution and stock had a pH of 2.5 and 2.5-2.75, respectively. To the liquor containing the stock was added 10 g. of an aqueous diethanolamine sulfate solution (30% DEA), immediately followed by 10 g. of sodium formate (as a 10% aqueous solution) and 12.5 g. (1.25% on white weight) Cr 2 O 3 (Koreon M in the form of a 50% solution). The mixture was then drummed for 30 minutes. The stock was checked for complete penetration of chrome and then neutralized with sodium bicarbonate (10% solution) to a liquor pH of 3.9 and a stock pH of 4.0-4.25. the total run in the chrome liquor was 21/2 hours. The resulting blue stock stood a one minute boil. The Cr 2 O 3 in the spent liquor was 1.1 g./l. | Method of chrome tanning wherein, after unhairing and bating, a water soluble amino compound is provided in an acidified hide stock solution prior to or simultaneously with addition of a chrome tanning agent. The amount of chrome tanning agent required in the charge, and therefore the amount of chrome in the exhaust liquor or effluent, is thereby substantially reduced, thus providing greater control over pollution due to chrome in leather manufacturing operations. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation of Application, filed under 35 U.S.C. §111(a) of International Application PCT/JP2010/072556, filed on Dec. 15, 2010, the contents of which are herein wholly incorporated by reference.
FIELD
[0002] The present invention relates to a wireless communication apparatus performing discontinuous receptions.
BACKGROUND
[0003] An online communication application is given as a service provided to a portable terminal (mobile station) such as a cellular phone. In the online communication application, the portable terminal periodically conducts transmissions and receptions. The portable terminal is requested to restrain power consumption though the transmissions and the receptions are periodically performed. Further, if the online service involves a long period of time expended till completing the transmission and the reception since the transmission and the reception have been started, a user of the portable terminal feels a stress as the case may be. The online service is therefore required to restrain the period of time expended till completing the transmission and the reception since the transmission and the reception have been started.
[0004] In an LTE (Long Term Evolution) mobile communication system pursuant to 3GPP (3rd Generation Partnership Project) standards, DRX (Discontinuous Reception) control exists even during SCH (Shared CHannel) communications. Hereafter, the DRX control will also be referred to as SCH-DRX control. In the LTE mobile communication system, a base station (eNB; eNodeB; evolved Node B) dynamically allocates an SCH wireless resource to a mobile station (UE; User Equipment) on a time base. Further, the base station takes an initiative to manage the allocations of the wireless resources at both of uplink and downlink. Herein, an uplink direction is defined as a direction to the base station from the mobile station, while a downlink direction is defined as a direction to the mobile station from the base station. On the occasion of a downlink transfer, the base station can detect occurrence of downlink transfer data and can therefore transfer the transfer data to the mobile station immediately without any delay. In contrast with this transfer, on the occasion of an uplink transfer, the mobile station side detects the occurrence of the uplink transfer data, and the mobile station requests the base station for the uplink wireless resource. In response to this request, the base station allocates the wireless resource to the mobile station. Hereafter, the mobile station actually transfers the transfer data to the base station by use of the allocated wireless resource.
DOCUMENTS OF PRIOR ARTS
Patent Document
[0005] [Patent document 1] Japanese Patent Application Laid-Open Publication No. 2009-531973
[0006] [Patent document 2] Japanese Patent Application Laid-Open Publication No. 2009-165133
[0007] [Patent document 3] Japanese Patent Application Laid-Open Publication No. H11-177524
[0008] [Patent document 4] Japanese Patent Application Laid-Open Publication No. 2002-171219
[0009] [Patent document 5] Japanese Patent Application Laid-Open Publication No. 2008-244526
SUMMARY
[0010] In the LTE communication system, there are a reception interval (period) in which the mobile station receives the data and a DRX (Discontinuous Reception) interval (period) in which the mobile station does not receive the data.
[0011] The mobile station transmits an SRS (Sounding Reference Symbol) to the base station in order to keep an uplink wireless resource. The base station transmits, based on the SRS given from the mobile station, a TA Command (Timing Advance Command) to the mobile station. The TA Command is a command for keeping uplink synchronization. The mobile station receiving the TA Command controls a reception interval. Specifically, the mobile station receiving the TA Command extends the reception interval. The extension of the reception interval elongates a period of time for which the mobile station is kept in a reception status, resulting in an increase in power consumption of the mobile station. Further, the mobile station receiving the TA Command starts up or restarts up a TA timer (Time Alignment Timer). When the TA timer expires, the mobile station is determined to get released from the uplink synchronization.
[0012] FIG. 1 is an explanatory diagram of the uplink synchronization in the LTE communication system. The base station (eNB) monitors the release from the uplink synchronization with the mobile station (UE) separately from the downlink synchronization. The base station manages the release from the uplink synchronization by use of the SRS (Sounding Reference Symbol) that is periodically transmitted by the mobile station. The base station, e.g., if the SRS is not transmitted for a predetermined period of time from the mobile station, determines that the uplink synchronization with the mobile station is released. The mobile station monitors the release from the uplink synchronization on the basis of the TA Command transmitted by the base station upon receiving the SRS. To be specific, the mobile station periodically transmits the SRS during the reception interval (time). The base station, upon receiving the SRS, transmits the TA Command to the mobile station. The mobile station starts up or restarts up the TA timer whenever receiving the TA Command, and determines that the uplink synchronization is released when the TA timer expires. When the uplink synchronization is released, the mobile station releases an allocated SR resource (control resource). Note that a TA timer value at the startup time is given from the base station. The TA timer value is notified through, e.g., notifying information given from the base station 200 . The TA timer value is defined as a period of time till the TA timer expires since the TA timer has been started up. The TA Command is a command (information) for keeping the uplink synchronization. The mobile station keeps the uplink synchronization (control resource) on the basis of the TA Command. The mobile station, when receiving data containing the TA Command etc, extends the reception interval.
[0013] Furthermore, the mobile station during SCH-DRX control does not perform a process of keeping the uplink synchronization. “The mobile station during the SCH-DRX control” represents the mobile station entering a DRX interval. That is, the mobile station during the SCH-DRX control does not transmit the SRS to the base station. Hence, unlike continuous reception control, there is a possibility that the uplink synchronization is released. This is because there is a possibility that the TA timer expires during the SCH-DRX control. If the uplink synchronization is released, it might happen that a considerable period of time is taken for transmitting the uplink data on the occasion of occurrence of the uplink data.
[0014] According to a first aspect, a wireless communication apparatus in which to alternately set a reception interval for receiving signals from another apparatus and a non-reception interval for not receiving the signals from another apparatus, includes:
[0015] a transmission unit to retain a wireless control resource used for wireless communications with another apparatus and exclusively possessed by the wireless communication apparatus;
[0016] a reception unit to receive signals containing data having at least one of first information and second information; and
[0017] a reception extension control unit to extend, when the data received by the reception unit contain the first information, the reception interval up to when first predetermined time elapses,
[0018] wherein the reception extension control unit, after extending the reception interval up to when the first predetermined time elapses and when the data received by the reception unit do not contain the first information, stops the extension of the reception interval.
[0019] The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
[0020] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is an explanatory diagram of uplink synchronization in an LTE communication system.
[0022] FIG. 2 is a diagram illustrating an example of MAC PDU.
[0023] FIG. 3 is an explanatory diagram of a method of transmitting an SR.
[0024] FIG. 4 is an explanatory diagram of a supplying method through an RA Procedure.
[0025] FIG. 5 is a diagram illustrating an example of a configuration of a mobile communication system in the embodiment.
[0026] FIG. 6 is a diagram illustrating an example of a timing schedule of a reception interval and a DRX interval in a mobile station.
[0027] FIG. 7 is a diagram illustrating and example of an operation flow of a reception extension control unit of the mobile station.
[0028] FIG. 8 is a diagram illustrating an example where the reception interval is extended.
[0029] FIG. 9 is a diagram illustrating an example where the reception interval is not extended.
[0030] FIG. 10 is a diagram illustrating an example where the extension of the reception interval is stopped.
DESCRIPTION OF EMBODIMENTS
[0031] An embodiment will hereinafter be described with reference to the drawings. A configuration of the embodiment is an exemplification, and the present invention is not limited to the configuration of the embodiment.
[0032] In the present embodiment, a mobile communication system using a method specified by LTE (Long Term Evolution) will be described by way of an example, however, the present invention is not limited to this system but can be also applied to communications systems exploiting other methods.
LTE Communication System
[0033] Descriptions of DRX control during SCH communications, downlink data reception and an uplink resource request in an LTE communication system, will be made.
DRX Control During SCH Communications
[0034] In the LTE communication system, there are a reception interval (period) during which a mobile station (user equipment (UE)) receives data and a DRX (Discontinuous Reception) interval (period) during which the mobile station does not receive the data. During the reception interval, a reception control unit of the mobile station is in an ON-status, and the mobile station can receive the data from a base station. During the DRX interval, the reception control unit of the mobile station is in an OFF-status, and the mobile station does not receive the data from the base station. The DRX interval is defined as a non-reception interval. In the LTE communication system, if there is no data to be transmitted and received even during starting up a packet transmission/reception service, transmission/reception control in the DRX interval may not be performed. With this contrivance, the mobile station can extend continuous speech time and continuous packet transmission/reception time even during transmitting and receiving the packets. Further, for realizing the continuous reception, when the mobile station receives the downlink data in the reception interval from the base station, it is specified by 3GPP standards that the reception interval is to be extended.
Reception of Downlink Data
[0035] In the reception of downlink data in the mobile station, the mobile station receives both of PDCCH (Physical Downlink Control Channel) data and PDSCH (Physical Downlink Shared Channel) data from the base station. PDCCH is defined as a physical channel for control at which to transmit and receive control information between the mobile station and the base station. PDSCH is defined as a physical channel for data at which to transmit and receive user data between the mobile station and the base station. The PDCCH data contain the control information about whether or not there is the downlink data addressed to each mobile station that is contained the PDSCH data. The determination as to whether or not there is the downlink data addressed to each mobile station that is contained the PDSCH data, is made based on whether or not there is an identifier of each mobile station that is contained in the PDCCH data. The PDSCH data contain the actual downlink data. The downlink data is transmitted in the way of being contained in, e.g., a MAC PDU (Media Access Control Protocol Data Unit). The MAC PDU contains a MAC header, a MAC SDU (Service Data Unit) and a TA (Timing Advance) command. The determination as to whether the MAC PDU contains the MAC SDU or not can be made by analyzing the header of the MAC PDU. The MAC SDU contains, e.g., e-mails and service data such as VoIP (Voice over Internet Protocol). The PDCCH data and the PDSCH data can contain information on whether the service is a real-time service or not.
[0036] FIG. 2 is a diagram illustrating an example of the MAC PDU. The example of FIG. 2 illustrates, from above, the MAC PDU containing the TA Command, the MAC PDU containing the MAC SDU, and the MAC PDU containing the TA Command and the MAC SDU. The MAC PDU, in the case of containing the TA Command, contains a header associated with the TA Command. Similarly, the MAC PDU, in the case of containing the MAC SDU, contains a header associated with the MAC SDU. The MAC header of the MAC PDU is analyzed, whereby it can be determined from a header type thereof whether the MAC PDU contains the MAC SDU or not.
[0037] Under the normal DRX control, the mobile station, if there is the control information indicating that the PDCCH data contains the downlink data addressed to the mobile station itself, extends the reception interval. In other words, under the normal DRX control, the mobile station does not extend the reception interval if failing to receive the PDCCH data but extends the reception interval if succeeding in receiving the PDCCH data irrespective of the success or failure (CRC-OK/NG) in the reception of the PDSCH data.
Uplink Wireless Resource Request
[0038] An uplink wireless resource request in the LTE communication system will be described. As a method of making a request for the uplink wireless resource, such two methods exist as a method of transmitting SR (Scheduling Request) by use of resource dedicated to PUCCH (Physical Uplink Control CHannel) for the uplink wireless resource request and a method of making the request through RA Procedure (Random Access Procedure).
[0039] FIG. 3 is an explanatory diagram of how the SR is transmitted. The former SR transmission method is that the mobile station having the uplink data transmits the SR for requesting the base station for the uplink wireless resource. The uplink wireless resource is a resource for transmitting the uplink data. A control resource (wireless control resource), which is already allocated to the mobile station, are used as an SR resource. An uplink wireless resource is a resource exclusively possessed and exploited by the mobile station for the wireless communications with the base station. Uplink synchronization is taken between the base station and the mobile station, which implies that there is the control resource allocated to this mobile station. The control resource is allocated to every mobile station. The mobile station transmits the SR to the base station by exploiting the control resource allocated to the self-station. The base station, upon receiving the SR transmitted in a way that exploits the control resource allocated to the mobile station, can specify the mobile station that has transmitted the SR by knowing which control resource is exploited. The mobile station (eNB) can discern the mobile station (UE) immediately after receiving the SR and can allocate the uplink wireless resource to the mobile station making the request for the uplink wireless resource. The mobile station allocated with the uplink wireless resource transmits the uplink data by making use of the uplink wireless resource. The SR (Scheduling Request) is, if the mobile station has the uplink data that is transmitted to the base station, transmitted for requesting the base station to allocate the uplink wireless resource.
[0040] FIG. 4 is an explanatory diagram of a method of making the request through RA Procedure. The latter method of making the request through the RA Procedure is that the operation starts from transmitting RA Preamble that exploits shared resources, i.e., the resources shared between or among the plurality of mobile stations. The mobile station making the request for the uplink wireless resource transmits the RA Preamble to the base station by making use of the shared resources. There is a case where the plurality of mobile stations simultaneously puts the requests, and hence the base station executes once an identification checking process about each mobile station. The base station allocates the resource for transmitting an identification ID to the mobile station and transmits information on the identification ID transmission resource (allocation information of the identification ID transmission resource) to the mobile station. The mobile station transmits the identification ID to the base station in a way that exploits the allocated identification ID transmission resource. The allocation of the uplink wireless resource is delayed longer by one roundtrip of this checking process than the SR transmission method. The base station, thereafter, allocates the uplink wireless resource to the mobile station and transmits information on the uplink wireless resource (allocation information of the uplink wireless resource) to the mobile station. The mobile station transmits the uplink data by making use of this uplink wireless resource. Further, if the requests for the uplink wireless resources get conflicted between or among the mobile stations, the mobile station excluded from the selection redoes the operation from the retransmission of the RA Preamble after the identification checking process, and therefore a delay of several tens to several hundreds of milliseconds (ms) occurs. The method of making the request via the RA Procedure is more time-consuming for transmitting the uplink data than the SR transmission method. Hence, it is desirable that the request for the uplink wireless resource is made by the SR transmission method.
Example of Configuration
[0041] FIG. 5 is a diagram illustrating an example of a configuration of the mobile communication system in the present embodiment. A mobile communication system 10 in the present embodiment includes a base station 200 (eNodeB) and a mobile station 300 (UE). The base station 200 and the mobile station 300 perform the wireless communications with each other. The mobile communication system 10 in FIG. 5 includes one base station 200 and one mobile station 300 , however, a system including a plurality of base stations and a plurality of mobile stations is also available.
[0042] The base station 200 includes a reception control unit 210 , a transmission control unit 220 , a TA control unit 230 , a data analyzing unit 240 , and an SCH-DRX control unit 250 . The base station 200 conducts the wireless communications with the mobile station 300 . The base station 200 is connected to a network via a higher-order base station management apparatus etc.
[0043] The reception control unit 210 receives radio signals from the mobile station 300 . The reception control unit 210 demodulates the received radio signals into reception data. The reception control unit 210 transfers the reception data to the data analyzing unit 240 .
[0044] The transmission control unit 22 transmits the radio signals to the mobile station 300 . The transmission control unit 220 modulates the transmission data into the radio signals.
[0045] The TA control unit 230 , when receiving an SRS (Sounding Reference Symbol) from the mobile station 300 , generates the TA Command as a response to this SRS.
[0046] The data analyzing unit 240 performs a data analysis of the radio signals transmitted from the mobile station 300 and received by the reception control unit 210 . The data analyzing unit 240 extracts the SRS out of the radio signals transmitted from the mobile station 300 and transfers the SRS to the TA control unit 230 .
[0047] The SCH-DRX (Shared Channel-Discontinuous Reception) control unit 250 controls the reception interval and the DRX interval.
[0048] Functions of the respective processing units of the base station 200 can be realized by use of a processor, a storage device, etc of a computer. The processor is exemplified such as a CPU (Central Processing Unit) and a DSP (Data Signal Processor). The storage device is exemplified such as a main storage device and a secondary storage device. The main storage device is exemplified by, e.g., a RAM (Random Access Memory) and a ROM (Read Only Memory). The secondary storage device is exemplified by, e.g., an EPROM (Erasable Programmable ROM) and a hard disk drive (HDD). Further, the secondary storage device can include a removable medium, i.e., a portable recording medium. The removable medium is a disc recording medium such as a USB (Universal Serial Bus) memory or a CD (Compact Disc) and a DVD (Digital Versatile Disc). The functions of the individual processing units can be realized in such a way that the processor loads programs stored in the secondary storage device into the main storage device and then executes the programs. The storage device can be stored with items of information of the uplink wireless resources allocated to the mobile stations, the control resources, etc.
[0049] The mobile station 300 includes a reception control unit 310 , a transmission control unit 320 , a TA control unit 330 , a data analyzing unit 340 , an SCH-DRX control unit 350 and a reception extension control unit 360 . The mobile station 300 can be actualized by using a dedicated or general-purpose computer such as a smartphone, a mobile phone and a car navigation system, or by using an electronic device mounted with the computer.
[0050] The reception control unit 310 receives the radio signals from the base station 200 . The reception control unit 310 demodulates the received radio signals into the reception data. The reception control unit 310 transfers the reception data to the data analyzing unit 340 .
[0051] The transmission control unit 320 transmits the radio signals to the base station 200 . The transmission control unit 320 modulates the transmission data into the radio signals. The transmission control unit 320 implements management to retain or release the uplink wireless resources.
[0052] The TA control unit 330 , upon receiving the TA Command, starts up a TA timer. A TA timer value is given beforehand by the base station 200 . The TA timer value is defined as a period of time till the TA timer expires since the TA timer has been started up. The TA control unit 330 , in the reception interval (including an extended case), generates the SRS at an interval of predetermined time and transmits the SRS to the base station via the transmission control unit 320 . A value (time) sufficient for receiving the TA Command since the mobile station 300 has transmitted the SRS, is set as the TA timer value.
[0053] The data analyzing unit 340 carries out the data analysis of the radio signals transmitted from the base station 200 and received by the reception control unit 310 . The data analyzing unit 340 extracts the TA Command and the MAC SDU out of the radio signals transmitted from the mobile station 300 . The data analyzing unit 340 transfers the TA Command to the TA control unit 330 . The data analyzing unit 340 processes the PDSCH data containing the downlink data addressed to the mobile station 300 itself. A determination as to whether or not the PDSCH data contain the downlink data addressed to the mobile station 300 itself is made based on whether or not there is an identifier of the mobile station 300 itself, which is contained in the PDCCH data.
[0054] The SCH-DRX control unit 350 controls the DRX interval. The SCH-DRX control unit 350 , when the DRX interval starts, instructs the reception control unit 310 to stop receiving the radio signals transmitted from the base station 200 . The stop of the reception of the radio signals enables the mobile station to reduce its own power consumption. The SCH-DRX control unit 350 , when the DRX interval terminates, instructs the reception control unit 310 to resume receiving the radio signals transmitted from the base station 200 .
[0055] The reception extension control unit 360 performs the control about whether the reception interval is extended or not. The reception extension control unit 360 controls an extension of the reception interval corresponding to the reception data, a service provided underway, etc. The reception control unit 310 goes on controlling till the reception interval terminates since the mobile station 300 has entered the reception interval. After the termination of the reception interval, the mobile station 300 enters the DRX interval.
[0056] Functions of the respective processing units of the mobile station 300 can be realized by use of the processor, the storage device, etc of the computer. The processor is exemplified such as the CPU (Central Processing Unit) and the DSP (Data Signal Processor). The storage device is exemplified such as the main storage device and the secondary storage device. The main storage device is exemplified by, e.g., the RAM (Random Access Memory) and the ROM (Read Only Memory). The secondary storage device is exemplified by, e.g., the EPROM (Erasable Programmable ROM) and the hard disk drive (HDD). Further, the secondary storage device can include the removable medium, i.e., the portable recording medium. The removable medium is the disc recording medium such as the USB (Universal Serial Bus) memory or the CD (Compact Disc) and the DVD (Digital Versatile Disc). The functions of the individual processing units can be realized in such a way that the processor loads the programs stored in the secondary storage device into the main storage device and then executes the programs. The storage device can be stored with items of information of, e.g., the TA timer value, the extension time of the reception interval, the user data, the services provided on the mobile station, etc.
Operational Example
[0057] The base station 200 , when receiving from the mobile station 300 the SR (Scheduling Request) by exploiting the control resource allocated to the mobile station 300 , determines the uplink wireless resource allocated to the mobile station 300 in a way that corresponds to a free status of the uplink wireless resource at that point of time. Namely, the base station 200 allocates the free uplink wireless resource at that point of time to the mobile station 300 . The base station 200 transmits to the mobile station 300 the information of the uplink wireless resource allocated to the mobile station 300 . The mobile station 300 transmits the uplink data by use of the uplink wireless resource allocated from the base station 200 . The information of the control resource and the information of the uplink wireless resource are managed by, e.g., the transmission control unit 320 of the mobile station 300 .
[0058] Moreover, the mobile station 300 , for keeping the allocated control resource, transmits in the reception interval the data containing the SRS for every predetermined time to the base station 200 . The reception control unit 210 of the base station 200 , upon receiving the data containing the SRS from the mobile station 300 , transfers the data to the data analyzing unit 240 . The data analyzing unit 240 , when extracting the SRS from the received data, transmits the SRS to the TA control unit 230 . The TA control unit 230 , when receiving the SRS, generates the TA Command for the mobile station 300 and transmits the TA Command to the transmission control unit 220 . The transmission control unit 220 transmits the data containing the TA Command to the mobile station 300 .
[0059] The reception control unit 310 of the mobile station 300 , when receiving the data containing the TA Command from the base station 200 , transfers the data to the data analyzing unit 340 . The data analyzing unit 340 , when extracting the TA Command from the received data, transmits the TA Command to the TA control unit 230 . The TA control unit 230 , upon receiving the TA Command, starts up the TA timer. If the TA timer starts underway, the TA control unit 230 stops the TA timer starting underway when receiving the TA Command, and newly starts up (restarts) the TA timer. The TA timer expires when the time of the TA timer value elapses since the TA timer has started. When the TA timer expires, the uplink synchronization with the base station 200 is released. That is, the control resource allocated to the mobile station 300 is released.
[0060] FIG. 6 is a diagram illustrating an example of a time schedule of the reception interval and the DRX interval that are set in the mobile station. The time schedule in FIG. 6 is the time schedule in the reception status of the mobile station. In the example of FIG. 6 , the reception interval and the DRX interval alternately appear on a time base. A length of the reception interval and a length of the DRX interval are previously set. The reception extension control unit 360 of the mobile station 300 extends the reception interval as the case may be. The reception extension control unit 360 and the SCH-DRX control unit 350 , even if the reception interval is extended, do not change the time when the DRX interval next to this reception interval terminates. The DRX interval is an interval in which the power consumption of the mobile station 300 is smaller than in the reception interval.
[0061] FIG. 7 is a diagram illustrating an example of an operation flow of the reception extension control unit of the mobile station. The reception extension control unit 360 of the mobile station 300 controls the extension of the reception interval. The reception extension control unit 360 operates in the reception interval of the mobile station 300 . It is herein assumed that the base station 200 has already allocated the uplink control resource to the mobile station 300 . The reception extension control unit 360 operates upon entrance of the mobile station 300 into the reception interval. Further, the transmission control unit 320 of the mobile station 300 , when the mobile station 300 enters the reception interval, transmits the SRS for keeping the uplink wireless resource to the base station 200 .
[0062] A start of the operation flow of the reception extension control unit in FIG. 7 is triggered by the mobile station 300 entering the reception interval.
[0063] In step S 101 , the reception extension control unit 360 determines whether the data reception gets successful or not. The reception extension control unit 360 determines whether or not the reception of the data (downlink data) transmitted via the PDSCH (Physical Downlink Sheared Channel) gets successful.
[0064] If the mobile station 300 does not receive the data transmitted via the PDSCH from the base station 200 or if the PDSCH data cannot be correctly received, the reception extension control unit 360 determines that the data reception gets unsuccessful (S 101 ; NO). At this time, the processing advances to step S 111 . Whereas if receiving the data transmitted via the PDSCH from the base station 200 , the reception extension control unit 360 determines that the data reception gets successful (S 101 ; YES). At this time, the processing advances to step S 102 .
[0065] In step S 102 , the reception extension control unit 360 determines as to [CRC (Cyclic Redundancy Check) OK/NG]. To be specific, the reception extension control unit 360 determines whether the data (MAC PDU) transmitted via the PDSCH from the base station 200 is normally received or not. Even when receiving the MAC PDU and if not normally received due to an error etc in the data, a subsequent process is disabled from being executed, and hence the reception extension control unit 360 checks whether the MAC PDU is normally received or not. If the MAC PDU is normally received (S 102 ; OK), the processing advances to step S 104 . The data transmitted via the PDSCH is transferred to the reception extension control unit 360 through the data analyzing unit 340 . Whereas if the MAC PDU is not normally received (S 102 ; NG), the processing advances to step S 105 . The determination in step S 102 may also be done by the data analyzing unit 340 .
[0066] In step S 103 , the reception extension control unit 360 determines whether the MAC SDU is contained in the normally received MAC PDU or not. It can be determined from the header type given by analyzing the MAC header of the MAC PDU whether the MAC PDU contains the MAC SDU or not (see FIG. 2 ). For example, the determination of whether the MAC PDU contains the MAC SDU or not is made based on whether or not the MAC header of the MAC PDU contains a MAC SDU subheader. If the MAC PDU contains the MAC SDU (S 103 ; YES), the processing advances to step S 105 . The MAC SDU contains the e-mails and the service data of VoIP etc. The service data of the email and VoIP etc are consecutively transmitted in many cases. Hence, if the MAC PDU contains the MAC SDU, there is a high possibility that the MAC SDU is transmitted from the base station 200 continuously, so that the reception interval is extended. Whereas if the MAC PDU does not contain the MAC SDU (S 103 ; NO), the processing advances to step S 104 . If the MAC PDU does not contain the MAC SDU, there is a low possibility that the MAC SDU is transmitted from the base station 200 continuously, so that the reception interval may not be extended. Further, if the MAC PDU does not contain the MAC SDU, the TA Command is contained in the MAC PDU in some cases. The TA Command is the command for keeping the uplink synchronization, and therefore the reception interval may not be extended due to the reception of the TA Command. The determination in step S 103 may be done by the data analyzing unit 340 .
[0067] In step S 104 , the reception extension control unit 360 makes a request for stopping the extension of the reception interval. This is because the reception interval may not be extended in the case of the MAC SDU not being contained in the MAC PDU. The reception extension control unit 360 , if the reception interval has already been extended and if entering the time of the extension in excess of the previous reception interval, makes a request for canceling the extension of the reception interval. Moreover, the reception extension control unit 360 , if the reception interval has already been extended but if still within the previous reception interval, makes a request for setting the reception interval back to the previous reception interval by canceling the extension of the reception interval. The reception extension control unit 360 , if the reception interval is not extended, does nothing because of there being no extension stopping target. After the process in step S 104 , the processing loops back to S 101 .
[0068] In step S 105 , the reception extension control unit 360 makes the request for extending the reception interval. The reception extension control unit 360 makes the request for extending the reception interval up to when a predetermined period of time elapses from the point of the present time. After the process in step S 105 , the processing loops back to S 101 . The reception interval is extended in such a case that there is a high possibility of the data being transmitted from the base station 200 . For example, in the case of [CRC NG] in step S 102 , there is the high possibility of the data being retransmitted from the base station 200 . Further, if the MAC PDU contains the MAC SDU (S 103 ; YES), there is the high possibility that the MAC PDU containing the MAC SDU is transmitted from the base station 200 continuously. Furthermore, if the real-time service is provided on the mobile station 300 (S 113 ; YES), there is the high possibility that the data are transmitted continuously from the base station 200 . The time to be extended may be set to a predetermined period of time since after the previous reception interval terminates in place of being set to when the predetermined period of time elapses from the point of present time.
[0069] The request in step S 104 or S 105 is reflected in the process in step S 111 . That is, the reception extension control unit 360 , based on the request in step S 104 or S 105 , stops extending the reception interval or extends the reception interval.
[0070] In step S 111 , the reception extension control unit 360 checks whether the reception interval expires or not. The reception extension control unit 360 compares the time when the reception interval expires with the present time, thereby determining whether the reception interval expires or not. If requested to extend the reception interval in step S 105 , the reception extension control unit 360 sets the reception interval requested to be extended as a new reception interval and determines whether this reception interval expires or not.
[0071] Further, if requested to stop extending the reception interval in step S 104 , the reception extension control unit 360 determines that the reception interval expires. If the previous reception interval (the reception interval before being extended) does not yet expire, the reception extension control unit 360 does not determine that the reception interval expires till the previous reception interval expires.
[0072] In the case of not determining that the reception interval expires (S 111 ; NO), the processing loops back to S 101 . Moreover, in the case of determining that the reception interval expires (S 111 ; YES), the processing advances to step S 112 .
[0073] In step S 112 , the reception extension control unit 360 determines whether or not the TA timer expires till the next reception interval. The TA timer is started up by the TA control unit 230 when receiving the TA Command from the base station 200 . The TA timer expires when the TA timer value (time) elapses since when started up. The reception extension control unit 360 compares a period of time (time A) up to the next reception interval from the point of the present time with a remaining period of time (time B) of the TA timer, thus determining whether or not the TA timer expires till the next reception interval. If the time A is shorter than the time B, the reception extension control unit 360 determines that the TA timer expires till the next reception interval. Whereas if the time A is longer than the time B, the reception extension control unit 360 determines that the TA timer does not expire till the next reception interval. If the TA timer expires till the next reception interval (S 112 ; YES), the processing advances to step S 113 .
[0074] While on the other hand, if the TA timer does not expire till the next reception interval (S 112 ; NO), the processing by the reception extension control unit 360 finishes, and the mobile station 300 enters the DRX interval. At this time, the TA timer does not expire till the next reception interval, and therefore the uplink synchronization is not released in the DRX interval. Hence, even when the uplink data occur in the DRX interval, the base station 200 can be requested for the uplink wireless resource by the SR transmission method. Namely, even when the uplink transmission data occur in the DRX interval, the uplink transmission data can be transmitted to the base station 200 without any delay.
[0075] In step S 113 , the reception extension control unit 360 determines whether the service provided on the mobile station 300 is the real-time service or not. The service provided on the mobile station 300 is managed by the mobile station 300 and the base station 200 . The real-time service includes, e.g., VoIP (Voice over Internet Protocol) service etc. The non-real-time service includes, e.g., an e-mail service. The real-time service is a service of which a quality is easy to decline if delayed. The mobile station 300 and the base station 200 recognize the service provided on the mobile station 300 . It is determined from a type of RB (Resource Block) being open underway and notified from the base station 200 whether the service is the real-time service or not. Further, the determination as to whether the service is the real-time service or not may also be done from QoS (Quality of Service) allocated on a service-by-service basis. If the service provided on the mobile station 300 is the real-time service (S 113 ; YES), the processing advances to step S 105 . If being the real-time service, the reception extension control unit 360 makes the request for extending the reception interval in order to transmit and receive the data continuously (S 105 ). Whereas if the service provided on the mobile station 300 is not the real-time service (S 113 ; NO), the processing by the reception extension control unit 360 finishes, and the mobile station 300 enters the DRX interval. When the mobile station 300 enters the DRX interval, the SCH-DRX control unit 350 sets the reception control unit 310 in an OFF status. Further, when the DRX interval expires, the SCH-DRX control unit 350 sets the reception control unit 310 in an ON status. The mobile station 300 enters the reception interval after the DRX interval has expired.
[0076] Herein, the process in step S 113 is eliminated, and, if the TA timer expires till the next reception interval (S 112 ; YES), the processing may advance to step S 105 . At this time, it does not happen that the TA timer expires in the DRX interval. Namely, the uplink synchronization (control resource) is kept in the DRX interval.
[0077] FIG. 8 is a diagram illustrating an example in which the reception interval is extended. FIG. 8 depicts an example of a sequence between the mobile station 300 (UE) and the base station 200 (eNB). The mobile station 300 entering the reception interval transmits the SRS to the base station 200 . The base station 200 transmits the TA Command as a response to the SRS to the mobile station 300 . At this time, the base station 200 , when having the downlink data to the mobile station 300 , transmits the data as the MAC PDU to the mobile station 300 in the way of being contained in the MAC SDU together with the TA Command. The mobile station 300 , when confirming that the received MAC PDU contains the MAC SDU, makes the request for extending the reception interval, whereby the reception interval is extended by the predetermined time. Moreover, the base station 200 , when further having the downlink data, transmits the data as the MAC PDU to the mobile station 300 in the way of being contained in the MAC SDU. The mobile station 300 , when confirming that the received MAC PDU contains the MAC SDU, makes the request for extending the reception interval, thereby extending the reception interval by the predetermined time. According to the mobile station 300 , if the received MAC PDU contains the MAC SDU, the reception interval is extended by the predetermined time.
[0078] FIG. 9 is a diagram illustrating an example where the reception interval is not extended. FIG. 9 depicts an example of a sequence between the mobile station 300 (UE) and the base station 200 (eNB). The mobile station 300 entering the reception interval transmits the SRS to the base station 200 . The base station 200 transmits the TA Command as a response to the SRS to the mobile station 300 . The base station 200 transmits the MAC PDU containing the TA Command to the mobile station 300 . At this time, when the base station 200 has none of the downlink data to the mobile station 300 , the MAC SDU is not contained in the MAC PDU. As in FIG. 9 , if the mobile station 300 receives the MAC PDU not containing the MAC SDU before the previous reception interval expires, the reception interval continues till the previous reception interval expires. That is, the mobile station 300 does not extend the reception interval if the received MAC PDU does not contain the MAC SDU.
[0079] FIG. 10 is a diagram illustrating an example in which the extension of the reception interval is stopped. FIG. 10 depicts an example of a sequence between the mobile station 300 (UE) and the base station 200 (eNB). The mobile station 300 entering the reception interval transmits the SRS to the base station 200 . The base station 200 transmits the TA Command as a response to the SRS to the mobile station 300 . At this time, the base station 200 , when having the downlink data to the mobile station 300 , transmits the data as the MAC PDU to the mobile station 300 in the way of being contained in the MAC SDU together with the TA Command. The mobile station 300 , when confirming that the received MAC PDU contains the MAC SDU, makes the request for extending the reception interval, whereby the reception interval is extended by the predetermined time. Moreover, the mobile station 300 further transmits the SRS to the base station 200 . The base station 200 transmits the TA Command as the response to the SRS to the mobile station 300 . The base station 200 transmits the MAC PDU containing the TA Command to the mobile station 300 . At this time, when the base station 200 has none of the downlink data to the mobile station 300 , the MAC SDU is not contained in the MAC PDU. As in FIG. 10 , the mobile station 300 , upon confirming that the MAC SDU is not contained in the received MAC PDU when the reception interval is extended with the expiration of the previous reception interval, makes the request for stopping the extension of the reception interval, whereby the extension of the reception interval is stopped. The mobile station 300 enters the DRX interval. The mobile station 300 , however, if the service provided underway is the real-time service, makes the request for extending the reception interval, thereby extending the reception interval.
Operation, Effects of the Embodiment
[0080] The reception extension control unit 360 of the mobile station 300 , if the received MAC PDU does not contain the MAC SDU, stops extending the reception interval. Further, the reception extension control unit 360 , whereas if the received MAC PDU contains the MAC SDU, extends the reception interval. The reception extension control unit 360 , if unable to receive the MAC PDU normally, extends the reception interval. Further, the reception extension control unit 360 , if the service provided underway on the mobile station 300 is the real-time service, extends the reception interval. The reception extension control unit 360 , if the TA timer expires in the DRX interval and if the service provided underway on the mobile station 300 is the real-time service, extends the reception interval.
[0081] According to the mobile station 300 , the uplink synchronization becomes hard to be released even when entering the DRX interval, and, if the MAC PDU does not contain the MAC SDU, the power of the mobile station 300 is saved by making the request for stopping the extension of the reception interval. Moreover, if the uplink data occur in the mobile station 300 , the mobile station 300 can promptly transmit the uplink data to the base station 200 by use of the control resource kept therein.
[0082] Moreover, it is the case where the service provided underway is not the real-time service that the TA timer expires in the DRX interval. Hence, in the mobile station 300 , even when the uplink synchronization is released due to the expiration of the TA timer in the DRX interval, the quality of service (QoS) is hard to decline. This is because if the service provided underway on the mobile station 300 is not the real-time service, there is the low possibility that the uplink data occur.
[0083] All examples and conditional language provided herein are intended for the pedagogical purposes of aiding the reader in understanding the invention and the concepts contributed by the inventor to further the art, and are not to be construed as limitations to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although one or more embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention. | A wireless communication device comprises a transmission unit for holding a wireless control resource exclusive to the wireless communication device, the wireless control resource being used in wireless communication to the other device; a reception unit for receiving a signal including data having at least one of first information and second information; and a reception extension control unit for extending the reception interval until a time where a first predetermined duration has elapsed, in a case where the data received by the reception unit includes the first information, the reception extension control device terminating the extension of the reception interval in a case where the reception extension control unit has extended the reception interval until the time where the first predetermined duration has elapsed and where the data received thereafter by the reception unit does not contain the first information. | 8 |
BACKGROUND OF THE INVENTION
In the manufacture of multi-layered elements, in particular of elements of III-V compounds like gallium arsenide, liquid-phase epitaxy becomes more and more employed. In contrast to elements on which semiconductor layers are deposited from the vapor-phase, life expectancy as well as efficiency are notably improved. For liquid-phase epitaxy, the surface of a substrate is brought into contact for a defined time with an oversaturated solution whereby a specific epitactic layer grows on the surface. In subsequent process steps, the same surface is brought into contact with another oversaturated solution in order to grow another epitactic layer. The process may be repeated many times. There is a trend in industry to ever thinner epitactic layers with ever-growing quality requirements. Thus, as the contact times between solution and surface decrease, the requirements as to purity of solutions, cleanliness of vessels, etc. increases. Also, it is necessary to remove one solution completely before the subsequent solution comes into contact with the surface. Finally, it is desirable to recover the solutions for further use, without contamination. Several implements and devices are already known in the art for the execution of multi-layered liquid-phase epitaxy. A first group of devices works with sliders which move between different chambers of a crucible which contain different solutions. U.S. Pat. No. 3,565,702 shows one embodiment. Another embodiment, with circular crucible and a circular slider, is shown in U.S. Pat. No. 3,881,037. For certain applications, these systems have the drawback of relatively complicated structure, of requiring high precision machined parts and of moving, with the substrate, an amount of a solution which then mixes with another solution. Also, the time of contact between substrate and solutions cannot be made sufficiently short. Also, as a result of abrasion of crucible parts, which slide upon each other, the solutions can become contaminated and the substrates, in particular epitactic layers, may be damaged by mechanical influences.
In another group of systems, the exchange of solutions on the semiconductor substrate is done by rocking. An example of this group is shown in IBM Technical Disclosure Bulletin, volume 14, No. 9, page 2850. Although this apparatus shows little admixture of solution residues with the subsequent solution, the contact time, however, is too long for many applications.
A third class of devices is provided with rotating crucibles in which the transport of liquids is by means of gravity. One example is shown in U.S. Pat. No. 3,858,553, another one in IBM Technical Disclosure Bulletin, volume 18, No. 5, page 1585. The crucibles rotate slowly and contact times between substrates and solutions are long. In more recent designs, there is a trend to shorten the contact time by employing centrifugal forces besides the force of gravity. The paper by Bauser, Schmid, Lochner and Rabe, in Japanese Journal of Applied Physics, volume 16, 1977, supplement 16/1, pages 457 through 460, as well as literature cited there, describe examples of such devices. The crucible by Bauser et al. allows short contact times between various solutions and semiconductor substrates. Furthermore, the solutions are recovered for further use without essential mutual mixture. A disadvantage can be seen in that the crucible consists of many parts, which need precise machining. During operation, the parts within the crucible slide upon each other, thus giving cause to contamination of the liquids. Finally, under the influence of centrifugal force, the solutions repeatedly are forced to flow through narrow gaps which would stop normal flow due to surface tension of the solution. Therefore, solutions of high surface tension cannot be used.
SUMMARY OF THE INVENTION
The object of the present invention is an apparatus for the manufacture of multi-layered semiconductor devices by means of liquid phase epitaxy. The apparatus is particularly simple and durable. It can hold two or more different solutions which are brought into contact, one after another, with semiconductor substrates without substantial intermixing. This allows the manufacture of multi-layer structures with a set of layers repeating as often as desired. Furthermore, the apparatus is suitable for extremely short contact times between each solution and the substrates. The flow rate of solution, and therefore the contact time, can be varied within wide limits. The simple design allows higher rotational speeds and the ensuing centrifugal forces are used to provide effective drying of the substrates after each contact with each solution. The high acceleration can also be used to oversaturate solutions under certain conditions. One embodiment operates by means of centrifugal force only, i.e. without the presence of gravitational forces and therefore appears suitable for space application.
According to the invention, the foregoing objects are achieved by means of a crucible containing several chambers that are interconnected with each other by channels. The chambers as well as the channels are arranged with regard to the rotational axis of the crucible so that upon changing rotational speed of the crucible the liquids flow from one chamber through a channel into the next chamber without mutually mixing.
The foregoing and other objects, features and advantages of the invention will be apparent from the following and more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1 and 2 illustrate schematically a top view and cross-section of a first embodiment of the rotatable crucible.
FIGS. 3 and 4 illustrate schematically a top view and cross-section of a second embodiment of a rotatable crucible.
FIGS. 5 and 6 illustrate schematically sections of a crucible chamber.
FIG. 7 illustrates schematically a cross-section of an embodiment for continuous manufacture.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a crucible or reactor 1 which contains six chambers. The crucible is a rotatable and preferably of round configuration attached to the upper end of a vertically arranged rotatable axis. While FIG. 1 gives a top view of the crucible, FIG. 2 shows a cross section along the line 2--2, which is arranged to show three chambers within the crucible and the interconnecting channels. As can be seen, the chambers which, together with the channels, constitute a closed loop, are arranged alternately close to the axis and the bottom of the crucible, or close to the circumference and the top of the crucible. The connecting channels always lead from the bottom of one chamber to the top of the subsequent chamber.
The described arrangement has the effect that a liquid, which assumedly is in top chamber 5, under the influence of gravitational forces flows through channel 6 into bottom of lower chamber 7. If the crucible now is rotated sufficiently rapidly around the axis indicated at 4, the resulting centrifugal force will drive the liquid out of chamber 7 through channel 8 into chamber 9. As long as the centrifugal force persists, the liquid will remain in chamber 9. If rotation of the crucible is slowed, the force of gravity will eventually overcome the centrifugal force and the liquid will flow or drain from chamber 9 through drain channel 10 into chamber 11. If the start/stop sequence of rotation of the crucible around axis 4 is continued, the liquid will flow from chamber 11 through chamber 12 and 13, eventually back into chamber 5. The circle can be repeated at will. It is obvious that several different liquids contained in chambers 5, 9 and 12, will be caused by repeated start/stop cycles to flow within the crucible without mixture between the various liquids.
The drawing of the crucible in FIGS. 1 and 2 is essentially simplified for ease of understanding. The crucible consists of a material suitable for conditions of liquid-phase epitaxy. Suitable materials are e.g. graphite, ceramics, silica glass, glass, stainless steel, etc. It is known to one skilled in the art how suitable materials are selected for each application. The crucible is attached to a rotatable axis which is only indicated by its center line 4. The axis is supported in appropriate bearings (not shown) below and/or above the crucible and is connected to a drive, e.g. an electrical induction motor. The crucible may comprise a cover, indicated by 3 in the drawing, which sits loosely on top of the crucible edge, or is attached thereto by suitable means. The cover also may, according to the application, be sealed hermetically. Normally, the crucible also requires a well-controlled heating. For example, it can be disposed within a vertical silica glass tube surrounded by an induction heating coil. The silica glass tube may be closed and contain a protective atmosphere. Alternately, the crucible may be evacuated or filled with a protective atmosphere through a hollow axis. Since all these details as well as many others are known to one skilled in the art, they are only mentioned here and not described. The substrates 15, on which epitactic layers are to be grown, are attached to a strip-like substrate holder 16. The substrate holder is inserted into an ascending channel. In FIG. 2, holder 16 is shown inserted into channel 8. Besides substrates 15, the strip may comprise a flow rate reduction or throttling means 17 (e.g. a valve) which reduces the cross-section of the channel and thereby reduces the flow rate of the liquid. Optionally, substrate holder 16 may be positioned in each of the ascending channels.
For operation of the device, the wafer loaded substrate holders are inserted into the channels and the chambers are filled with the required solutions. If, for example, gallium arsenide substrates are to be covered alternately by P- and N-conductive layers, gallium arsenide containing a conductivity determining substance or the components of such a substance is dissolved in a gallium melt. In one of the inner bottom chambers, a gallium melt with dissolved P-conductive gallium arsenide is introduced, and another chamber provided with a melt of dissolved N-conductive gallium arsenide. The crucible is now heated until the components are completely dissolved, and by control of temperature or, sometimes by means of "saturation substrates", a saturated solution is prepared. The solution is then supersaturated by carefully lowering the temperature, either in steps or continuously. Sometimes it is desirable to remove portions or irregular substrate surfaces by dissolving some substrate material. If this state is reached, the before-described start/stop cycles may be begun. This will cause alternatively the first supersaturated solution melt and then the other one to wash past the substrates. In each pass of a melt, an epitactic layer will grow on the substrates. The process is repeated until the desired number of layers has grown. Now, or possibly after a cool-down period, the substrate holder with the attached substrates is removed from the crucible. Another substrate holder with new substrates may be inserted for further epitactic deposition.
During liquid-phase epitaxy by means of the above-described apparatus, layers of both conductivities are deposited epitactically in alternation on gallium arsenide substrates. The deposition usually occurs at temperatures between 600° and 900° C. from a supersaturated solution. The solution consists of liquid gallium in which doped gallium arsenide is dissolved. Supersaturation of the solution is achieved by controlled lowering of the temperature. In the embodiment, of the crucible as just described, up to three solution melts may circulate a tone time. The melts will alternatively wash past the substrates at a high flow rate during a short, well defined time, thereby depositing a new epitactic layer each time. There is substantially no intermixing between the solutions because after transport of a solution from one chamber to the next, no residue remains. The substrates also retain no significant residual solution since they are dried substantially under the influence of centrifugal force. As opposed to hereto known apparatus, this device has no mutually moving parts and therefore no friction between surfaces which would constitute a contamination risk for the solutions. It is advantageous to make the crucible from a material which is not wetted by the solutions, e.g. graphite, if a solution of gallium arsenide in gallium is used. Because of their surface tensions, the solutions will not enter ascending channels as long as the crucible stands still. Only when a threshold rotational speed is attained, the centrifugal force will then overcome the surface tension of the liquid as the latter enters the channel. The liquid then experiences the acceleration b z according to the formula: b z =rφ 2 , whereby r is the distance from the center axis and φ the angular velocity of the crucible in rad/s. At the time t therefore r=r 0 ·cosh φt and the flow rate V=r 0 ·φ. sinh φ, e.g. in other words the flow rate increases almost exponentially. At a rotational speed φ=3000 rpm=300 rad/s and r 0 -5 cm, the flow rate V=1500 cm/s·sinh 300·t. That means, after 3 milliseconds, V=1500 cm/s at a radius of 8 cm. Because of friction and viscosity, the flow rate is somewhat lower.
Since the flow rate increases rapidly in the channel, there may be a problem of a too rapid current flow if the cross-section of the channel is uniform. Therefore, it is advantageous to design the channel so that, in the direction of flow, its cross-section decreases proportionally to the reciprocal value of the speed of liquid. This measure is not necessary, however, if the crucible is designed to hold substrates in the chambers rather than in the channels.
FIG. 3 shows the second embodiment of the device. Since the transport of liquids here is due solely to the change between rotational acceleration and centrifugal force, gravity is not required at all. This embodiment can be used therefore in a gravitation-free space or environment.
Crucible 18, as shown in FIGS. 3 and 4, is rotatable around an axis which is not shown but only indicated by line 26, similar to the embodiment of FIGS. 1 and 2. Crucible 18 can also be heated and can be opened for insertion as well as removal both of liquids and substrates. Since these particulars are not only known to one skilled in the art but have also been discussed with reference to FIGS. 1 and 2, no more discussion need be made here. Crucible 18 contains six chambers, i.e. 19, 20, 21 etc. which are interconnected by channels 22. Strip-like substrate holders 23 holding substrates 24 are arranged within the channels.
In contrast to crucible 1, the chambers of crucible 18 are spaced at the same distance from the crucible axis 26. The transport of liquid, which in crucible 1 occurs by alternate action of gravitational and centrifugal force, now occurs by alternating rotational velocity. A liquid contained in chamber 19 will, if the crucible rotates counterclockwise, collect at the peripheral side of the chamber. If braking occurs, i.e. a counterclockwise rotational acceleration of the liquid will flow through channel 22 into chamber 20. The liquid thereby washes past the substrates 24, which are attached to substrate holder 23, and thereby deposits an epitactic layer on these substrates. Channel 22 leads from one end surface of the cylindric chamber 19 to the other end surface of cylindric chamber 20. The channel leaves chamber 19 almost radially of its axis while entering tangentially into chamber 20. The liquid, which flows through channel 22 at high speed, is led into chamber 20 in a spiral flow. This has the effect that the liquid does not pass chamber 20 immediately in direct flow into chamber 21 but rather circulates within the chamber in a spiral fashion. The cycle times of the acceleration start/stop cycle are adjusted so that the deceleration, under the influence of which the liquid flows through channel 22, will be about zero when the liquid enters chamber 20. Due to its tangential guiding, the kinetic energy of the entering liquid is controlled. It is obvious that acceleration times and amount of liquids have to be determined in considering the speed of flow, viscosity and other parameters that all have to match, to avoid a mutual mixing of several liquids existing in several chambers of crucible 18. If, for example, the volume of a liquid at most equals the volume of a channel 22, the liquid, which travels e.g. from chamber 19 into chamber 20, will arrive there only after the liquid, which has previously occupied chamber 20, is completely evacuated. Therefore, if the volume of the channels should be kept low, it is advantageous to fill each second chamber only with liquid in order to avoid any mixing of liquids.
Transport of liquids, which is caused by periodic increase and decrease of revolution per minute in one and the same direction, can as well be caused by a periodic change of direction. It is essential only that the change of acceleration in amount as well as in time is adapted to the flow rate of the liquid. FIGS. 5 and 6 show a cross-section vertically to the cylinder axis of chamber 19, as well as a section parallel to the axis. All other chambers of the crucible are identical. The dashed line in the incoming channel 22 shows how the liquid flows through the channel under the influence of acceleration, how it is led tangentially into chamber 19 and then spirals along the wall in order to decelerate. Deceleration is necessary to ascertain that the liquid does not flow into the outlet channel before the solution is entirely evacuated, in the same cycle, from the preceding chamber. The liquid rotates within the chamber sufficiently long to overcome the counter acceleration of the crucible, i.e. to attain the rotational speed necessary to transport the liquid through the next channel in the subsequent cycle.
It is readily appreciated that very high acceleration forces can be applied in the last described embodiment. If the total diameter of the crucible is in the range of 10 to 30 cm, rotational speeds in the order of 5000 rpm are possible without difficulty. The speed variations, necessary for liquid transport are small in comparison. The high resulting centrifugal forces also help to break oxide layers that may build up on the liquid surfaces since the density of oxide is low as compared to that of the solution. Furthermore, oversaturation of solutions may be controlled by rotational speed, i.e. by centrifugal force if the solution and the dissolved substance are of different specific weight.
The chambers which are described in cylindric form in the drawings may have many other shapes, e.g. that of a sphere. The embodiment according to FIG. 7 is suitable for the manufacture of semiconductor elements in large numbers in a continuous process. The device is shown in a cross-sectional view and in simplified form. Within a tube-like rotatable furnace 27, e.g. a rotatable susceptor of graphite or metal with a non-rotatable high frequency induction coil 34, a stack of equal crucibles 28 is arranged so that the rotation of the furnace around its vertical axis is transferred to the crucibles. A loader indicated by 35 feeds pre-heated crucibles one after the other from the bottom into the furnace where they are heated with sufficient precision to process temperature, then moved through the process and finally removed by a similar unloader 36 from the top of the furnace. Inserting as well as removal of crucibles is preferably made in a moment of stopped rotation.
The crucibles are functionally similar to those described with reference to FIGS. 3 to 6. There is the difference, however, in that a vertical connecting inlet pipe 29 leads into the first chamber 30 of each crucible from the top. A matching connecting outlet pipe 32 leaves the last chamber 31 of each crucible at the bottom. Furthermore, there is no connecting channel between neighboring chambers 31 and 30. The chambers and channels of the crucible do not constitute a closed cycle, in contrast to previously described embodiments. The liquids flow through each chamber of each crucible once in order to flow from the last chamber into the first chamber of the next lower crucible. Rotational motion of the furnace, or the stack of crucibles, respectively, is controlled in connection with the rise of the crucible stack so that the solutions are always at the same level with relation to the heating zone. Rising crucibles, therefore, travel from a pre-heating zone in the lower part of the furnace through a zone of epitactic deposition in the center region of the furnace into a cool down zone in the upper region. The solutions which cause deposition of epitactic layers are always kept in the center region, i.e. the deposition region. Crucibles are inserted from the bottom into the pre-heating region and withdrawn at the top from the cool down region. The process continues without interruption until the liquids are consumed or depleted. They may be withdrawn in a crucible which contains no substrates, and may be replaced by new liquids in a similar way.
Drive motor 33 is indicated to set the furnace 27 into rotation. Crucibles 28, e.g. may be guided by tracks and corresponding recesses. Induction heater 34 heats the crucibles to the necessary temperature. A feed arm 35 feeds new pre-heated crucibles and a second unloader arm 36 removes crucibles that have passed the process. Semi-conductor devices with many different layers may be made in great numbers at low cost by means of the embodiment depicted in FIG. 7. The process is practically a continuous one, as even an exchange or replenishment of liquids does not cause considerable interruption.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that changes in form and detail may be made therein without departing from the spirit and scope of the invention. | In a crucible or reactor for making multi-layered semiconductor devices by means of liquid-phase epitaxy, different supersaturated solutions are brought into contact with semiconductor substrates for short times. Transport of the solutions occurs by alternating acceleration. Either gravity alternates with centrifugal force, or a positive rotational acceleration alternates with a negative one. Chambers within the reactor are interconnected by channels so that the alternating forces acting upon the solutions cause these to flow in a preferred direction without mixing with each other. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention is in the area of biosensors, and encompasses nanoparticles whose presence is detectable by two means, magnetic and visual. The nanoparticles have a core/shell structure with a magnetic core and a fluorescent semiconductor shell.
[0003] 2. Description of Background Art
[0004] Passivated magnetic nanoparticles with core shell structure have recently been described in U.S. patent application Ser. No. ______ filed Jan. 31, 2003 (Navy Case 83,289) and based on provisional U.S. patent application Ser. No. 60/307/693 filed Apr. 4, 2002 by the inventors of this patent application, both applications are incorporated herein by reference in their entirety. In the invention described in the incorporated patent applications, nanoparticles having a core/shell structure with a magnetic core and a metal oxide shell are described and claimed. The shell passivates the core to protect against further oxidation.
[0005] U.S. Pat. No. 6,048,515 describes multilayered nanoparticles having a magnetic core and at least two layers of coatings thereon. The particles of this invention may be detected magnetically or visually because of the reddish brown color of the core. The nanoparticles of this invention are said to be useful for diagnostic and therapeutic purposes.
OBJECTS OF THE INVENTION
[0006] An object of this invention is to produce core/shellstructured nanoparticles having properties which provide for more than one manner of detection. The properties are magnetic detection by virtue of the nanoparticles magnetic core, and visual detection by virtue of the particles fluorescent semiconductor or a surface plasma resonances in the outer shell.
[0007] Another object of this invention is to provide a new diagnostic tool.
[0008] Another object of this invention is to provide a synthesis route for magnetic/fluorescent nanoparticles.
[0009] Another object of this invention is to provide nanoparticles with dual detection properties for use in biomedical applications and biodetection schemes.
SUMMARY OF THE INVENTION
[0010] Magnetic nanoparticles based on iron oxide core have been synthesized in a variety of methods including sonochemical, photochemical, as well as other solution chemical methods. Using the reverse micelle system it is possible to form a shell semiconductor layer that makes the magnetic nanoparticles fluoresce. This semiconductor layer then adds to the applicability of the particle by altering the electronic properties of the particle while maintaining the magnetic properties of the core. For biomedical applications this semiconductor layer provides an additional fluorescence without further functionalization. As a result, the core/shell nanoparticles can be used in a variety of biological applications where their magnetic properties are most desirable.
[0011] The advantages of using chemical routes to produce the core/shell magnetic/fluorescent nanoparticles of this invention include the ability to produce larger quantities of material while achieving better chemical homogeneity due to mixing of the constituents at the molecular level.
[0012] The focus of this synthesis was the development of a magnetic nanoparticle which also has fluorescent properties. To this end, this invention expands on core/shell synthesis to now grow a semiconductor shell. The semiconductor, CdS, CdSe and other group III and group V fluorescent semiconductors give the nanoparticles of the invention fluorescent properties while maintaining the magnetic properties of the core.
[0013] The advantages of the synthesis comes in two parts, first it allows for the construction of a hybrid magnetic semiconductor which can be used in dual detection schemes, both optically and magnetically. The use of a QDot (nanoparticle semiconductor) has many advantages over traditional dyes, such as narrower emission and excitation bands and resistance to photobleaching.
[0014] Currently, in linear flow assays using colloidal nanoparticles, the nanoparticles travel with the solvent front through a porous membrane to a conjugated pad. Here the functionalized nanoparticles stick giving a visual qualitative reading of whether an analyte is present or not. Using this technique in the field, a Corpman could use the visual detection of a test strip for various biological agents. In cases where the visual detection and evaluation might be ambiguous, the magnetic properties would not be. The same test strip could be be sent to a field hospital where technicians could use a magnetic strip reader and quantify the results.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 . shows the core/shell structure of the invention.
[0016] FIG. 2 . shows the general synthesis route for the invention
[0017] FIG. 3 . shows fluorescence spectra of semiconductor and iron semiconductor materials.
[0018] FIG. 4 . shows TEM of CdS-FeO x aggregates of 3 nm nanoparticles.
DETAILED DESCRIPTION OF THE INVENTION
[0019] In this invention, metal salts of Fe, Co or Ni or other ferromagnetic metals or alloys thereof or mixtures thereof were dissolved within the aqueous core of a reverse micelle system formed using surfactants in organic solvents. The surfactants used in the micelle system are quateranary ammonium salts, polyoxylethoxylates, and sulfate esters. Examples of surfactants are cetyltrimethylammonium bromide, nonyphenolpolyethoxylate 4 and 7 (NP-4 and NP-7), sodium dodecylbenzenesulfonate, and bis(2-ethylhexyl)sulfosuccinic ester. Organic solvents used include chloroform, toluene or any organic solvent compatible with the surfactant and micelle synthesis system.
[0020] In practice, the metal salt solution which will form the nanoparticle core is mixed with the organic surfactant solution to form the micelle solutions. A sodium borohydride reducing solution is also mixed with organic surfactant solution. The two micelle solutions are mixed and allowed to react to effect reduction of the metal salt to the core ferromagnetic metal. As well as sodium borohydride, lithium borohydride may also be used as can any equivalent reducing agent
[0021] Following isolation of the core magnetic nanoparticles, the nanoparticles are treated with a metal sulfide such as sodium sulfide or equivalents thereof which results in formation of metal sulfide monolayer on the surface of the core material which act as seed for epitaxial growth of the fluorescent semiconductor shell layer. To form the shell, sodium sulfide and the fluorescent semiconductor precursor are alternatively added to the sodium sulfide treatment mixture. This synthetic procedure is outlined in FIG. 2 . The semiconductor precursor is a salt of the semiconductor such as a nitrate which is added alternatively with sodium sulfide to the sulfide treated core material to form the fluorescent semiconductor. Semiconductors useful in this invention are CdS, CdSe, And other fluorescent semiconductors of group III or group V.
[0022] It must be recognized that during isolation and reaction of the magnetic core metal nanoparticles, some of the magnetic nanoparticles may be oxidized to metal oxide so that the core material may indeed be ferrimagnetic, as demonstrated for iron, Fe, Fe 3 O 4 and or MFe 2 O 4 where M is Fe, Co, or Ni. Also it must be recognized that the whole core/shell structure may be a gradient composite material of Fe(FeO)FeSCdS. However, the end result is the same, a nanoparticle with a magnetic core and a fluorescent semiconductor shell.
[0023] In this invention, the preferred fluorescent semiconductors are cadmium sulfide (CdS), and cadmium selenide (CdSe). Other suitable fluorescent semiconductors for use in the invention are semiconductors of group V and group III with fluorescent properties. The magnetic metal core diameter ranges from about 2 to about 50 nm, while the shell thickness ranges from about 0.5 to about 50 nm. The core materials are selected to be a ferrimagnetic metal oxide or a ferromagnetic metal. The ferrimagnetic oxides include Fe 3 O 4 , or MFe 2 O 4 where M is Fe, Co, or Ni and the ferromagnetic metals include Fe, Co, or Ni or alloys thereof or mixtures thereof. The core is coated with CdS or CdSe or equivalents thereof or mixtures thereof to provide fluorescent semiconductor nanoparticles.
[0024] Dynamic light scattering as well as transmission electron microscopy (TEM) is used to determine particle size. FIG. 4 . shows a TEM micrograph of aggregates of 3 nm particles of core/shell nanoparticles of CdS shell over an FeO x core. Composition of the nanoparticles is determined by inductively coupled plasma, and the nature of the core is determined by x-ray absorption fine structure measurement.
[0025] The magnetic properties of the nanoparticles of this invention are determined using s SQUID magnetometer over a temperature range of 10K-300K. The particles have a magnetization of ˜11-15 emu/g at 100 G. Due to the large diamagnetic contribution from the semiconductor, the magnetization decreases as the field increases.
[0026] Fluorescent properties of the nanoparticles of this invention are measured using a spectrofluorometer over a wavelength of 280-450 nm for excitation scans and 380-750 nm for emission scans. FIG. 3 . demonstrates that the fluorescent properties of the nanoparticles of the invention are very similar to micelle generated CdS nanoparticles. Thus the core/shell nanoparticles of this invention possess fluorescent properties similar to the semiconductor, with the added property of a magnetic signal. Typically fluorescence detection has the disadvantage of suffering from false readings due to photobleaching and other effects. The added magnetic detection feature allows for clinical verification without further sampling or sample preparation. FIG. 3 . shows the spectral results of six experiments comparing fluorescent semiconductors (Qdots) with Qdot coated magnetic particles. Parenthetically, results show a 10% increase in fluorescence due to the presence of an external magnetic field. At the left of FIG. 3 . is shown tracings of excitation scans and on the right are shown tracings of emission scans. In an excitation scan, the emission monochromater is held fixed while the excitation monochromater is scanned. In an emission scan the reverse takes place, excitation monochromater is held fixed and the emission monochromater is scanned.
[0027] FIG. 3 . shows the spectral results of six experiments comparing fluorescent semiconductors (Qdots) with Qdot coated magnetic particles. Parenthetically, results show a 10% increase in fluorescence due to the presence of an external magnetic field. At the left of FIG. 3 . is shown tracings of excitation scans and on the right are shown tracings of emission scans. In an excitation scan, the emission monochromater is held fixed while the excitation monochromater is scanned. In an emission scan the reverse takes place, excitation monochramater is held fixed and the emission monochromater is scanned.
SYNTHESIS
[0028] Colloidal nanoparticles of iron were synthesized using reverse micelles. 219 mg iron (II) chloride dissolved in 1.6 ml deionized water was used as the aqueous core precursor. 191 mg sodium borohydride was dissolved in 1.5 ml of deionozed water for use as the reducing agent. The surfactant solution was prepared using 28.0 grams of cetyltrimethylammonium bromide (CTAB) dissolved in 200 ml chloroform. The aqueous metal solution was mixed with 50 ml CTBA solution and placed in a flask under flowing nitrogen. The sodium borohydride solution was mixed with 50 ml CTAB solution for 4 minutes to degas and homogenize. The sodium borohydride/CTAB solution was added to the iron chloride/CTAB and allowed to react with magnetic stirring under flowing nitrogen for 45 minutes.
[0029] To 0.05 gm of colloidal iron nanoparticle was added 0.01 M sodium sulfide, the amount add depends on the amount of metal colloide being used.
[0030] Following the sulfide addition, alternative additions of ˜0.1 M cadmium nitrate and sodium sulfide were made until 3 ml of each was added. Because of low solubilities there is virtually no free CdS in solution and this results in shell growth rather than nucleation. The reaction products are recovered using magnetic separation.
[0031] Colloidal cadmium selenide for use as a shell material was synthesized by the methods reported by Tian et al. J. Phys. Chem. 1996, 100, 8927-8939; and Kortan et al. J. Am. Chem. Soc. 1990, 112, 1327-1332; both references incorporated herein by reference. The colloidal CdSe was then used in shell synthesis as outlined above. | This invention comprises nanoparticles for use with biosensors. The nanoparticles have core/shell architecture. The nanoparticles can be detected by two means, magnetic and optical by virtue of the nanoparticles magnetic core and fluorescent semiconductor shell. Methods of making the nanoparticles and their composition are described. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 2004-058391, filed on Mar. 3, 2004, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a feeding structure for a gyro rotor in a gyrocompass which includes a liquid tank containing a supporting liquid therein, a gyrosphere which floats in the liquid tank by means of a supporting liquid and whose central portion is rotatably supported by a center pin provided in an upper portion of the liquid tank, and a gyro rotor incorporated in the gyrosphere.
2. Description of the Related Art
The following publication is known as a document relating to the gyrocompass having a center pin.
“konpasu to jairo no riron to jissai (Theory and practice of compass and gyro)” published on Oct. 1, 1971 by Kaibundou Shuppan Kabushiki Kaisha; Authors: Torao Mozai and Minoru Kobayashi
FIG. 5 is a cross-sectional view illustrating a general configuration of a gyrocompass having a center pin. Reference numeral 1 denotes a computation and follow-up control unit which is a portion which controls the power supply of the apparatus and various arithmetic operations and is in charge of follow-up control for maintaining the relative angle between a gyrosphere and a liquid tank by detecting the position of the gyrosphere. The computation and follow-up control unit 1 mainly consists of a gear mechanism for follow-up and printed board circuits.
Reference numeral 2 denotes a vibration proofing mechanism for maintaining a liquid tank unit substantially horizontally by inclination like a pendulum and for absorbing the vibrations of a ship in the longitudinal and transverse directions of the ship when the ship has rocked.
Reference numeral 3 denotes a liquid tank unit which is suspended in the vibration proofing mechanism 2 . In the liquid tank unit 3 , a liquid tank 4 has a gyrosphere 5 and an electrolyte (supporting liquid) 6 incorporated therein. The gyrosphere 5 has a gyro rotor 7 incorporated therein, and floats in the liquid tank 4 by means of the supporting tank 6 , and its central portion is rotatably supported by a center pin 8 provided in an upper portion of the liquid tank.
FIG. 6 is a perspective view illustrating a feeding structure for the gyrosphere 5 . Two dish-shaped electrodes 9 , which are disposed in close proximity to and in face-to-face relation to each other through the supporting liquid 6 , are respectively formed at a lower portion of the liquid tank 4 and a lower portion of the gyrosphere 5 . Electric power is fed from an external power supply 10 to the gyro rotor 7 incorporated in the gyrosphere 5 through the center pin 8 and the dish-shaped electrodes 9 . It should be noted that the surface of the gyrosphere other than the electrode is insulated.
FIG. 7 is a cross-sectional view illustrating the details of the feeding structure through the center pin. The tip of the center pin 8 is tapered, and this tip and a jewel bearing 11 provided on the gyrosphere side form a pivot, which allows the gyrosphere 5 floating in the supporting liquid 6 to be supported rotatably vertically and horizontally. Meanwhile, a small amount of mercury 14 is filled in a gap between a tip metal portion 8 a of the center pin and a pot-like metal portion 13 conducting with a terminal 12 on the gyrosphere side, thereby forming one feeding circuit from the center pin 8 to the gyrosphere 5 . Reference numeral 15 denotes insulating oil such as Demnum (trade name; product of Daikin Industries, Ltd.) for insulating the mercury 14 and the supporting liquid 6 , and numeral 16 denotes an O-ring for sealing the entry of the supporting liquid into the gyrosphere.
The gyro rotor 7 is connected to the one feeding circuit through the center pin 8 and the other feeding circuit for allowing an electric current to flow through the supporting liquid 6 by the dish-shaped electrodes 9 respectively formed at the lower portion of the liquid tank 4 and the lower portion of the gyrosphere 5 in face-to-face relation to each other, and the gyro rotor 7 rotates at high speed inside the gyrosphere.
FIG. 8 is a diagram explaining a deviation detecting mechanism in the follow-up control for causing the liquid tank 4 to follow up the gyration of the gyrosphere 5 . A pair of (two) follow-up electrodes 17 a and 17 b are provided on an inner wall of the liquid tank 4 at positions opposing an equatorial portion of the gyrosphere 5 and spaced apart from each other by 180°. A belt-shaped electrode 18 , which is slightly shorter than 180° (2° each at both ends), is formed at the equatorial portion of the gyrosphere 5 , and a difference in resistance between supporting liquid resistors Ra and Rb between both ends 18 a and 18 b of the belt-shaped electrode 18 and the follow-up electrodes 17 a and 17 b is detected by a Wheatstone bridge.
The belt-shaped electrode 18 is connected to the dish-shaped electrode 9 at the lower portion of the gyrosphere and is set at the same potential, and is connected to one terminal of the external power supply 10 through the dish-shaped electrode 9 . The gyro rotor 7 is connected between this dish-shaped electrode 9 and the tip metal 8 a of the center pin 8 , and electricity is fed thereto.
The follow-up electrodes 17 a and 17 b are connected to both ends of a primary winding of a transformer 19 for forming a Wheatstone bridge, and a midpoint of the primary winding is connected to one terminal of the external power supply 10 via a resistor 20 for current regulation. In a steady state, Ra=Rb, and the Wheatstone bridge is balanced and the induced voltage to a secondary winding of the transformer 19 is zero.
When the gyrosphere 5 gyrates in the direction of arrow P, and the relative angular relationship with the liquid tank 4 is offset about the vertical axis, Ra≠Rb, and a deviation (error voltage) in consequence of the imbalance of the Wheatstone bridge is induced in the secondary winding of the transformer 19 , so that a deviation signal E is obtained through an amplifier 21 . The amplitude of this deviation signal E represents a deviation angle, and the phase the gyrating direction.
The follow-up control unit 1 has the follow-up function whereby the gear mechanism is driven on the basis of this deviation signal E to simultaneously rotate the vibration proofing mechanism 2 and the liquid tank unit 3 in the direction of Q about the vertical axis, thereby correcting the relative angular relationship between the gyrosphere 5 and the liquid tank 4 such that the Wheatstone bridge becomes balanced.
The supporting liquid 6 is an electrolyte whose major agent is benzoic acid. Further, the specific gravity of the supporting liquid 6 has been adjusted by dynamite glycerin so that the gyrosphere 5 is always set in a floating state with respect to the ambient temperature.
The gyrocompass having the above-described conventional structure has the following problems.
(1) Mercury is used in a feeding route through the center pin, and it is desirable not to use mercury in the light of the protection of the global environment. (2) If mercury is used in the electrolyte, ions are adsorbed on the center pin surface, the mercury surface, and the pot-like metal portion of the gyrosphere due to the electro-capillarity phenomena, and the intermolecular force of ions acts as a restraining force and hampers the “frictionless free rotation of the gyrosphere,” exerting an adverse effect on the accuracy. As a measure, this problem can be solved by interposing the insulating oil 15 such as Demnum (tetrafluoroethylene) or the like between the mercury 14 and the supporting liquid 6 , as explained with reference to FIG. 7 , but this insulating oil is not friendly to the global environment, either.
SUMMARY OF THE INVENTION
The object of the invention is to provide a gyrocompass which is capable of feeding electricity to a gyro rotor without using a harmful substance in the feeding route into a gyrosphere and realizing follow-up accuracy equivalent to conventional one.
The invention provides a gyrocompass having: a liquid tank which contains a supporting liquid therein; a gyrosphere which floats in the liquid tank by means of the supporting liquid and whose central portion is rotatably supported by a center pin provided in an upper portion of the liquid tank; a gyro rotor incorporated in the gyrosphere; two dish-shaped electrodes respectively disposed at a lower portion of the liquid tank and a lower portion of the gyrosphere, and opposed through the supporting liquid; and a pair of follow-up electrodes respectively disposed in a vicinity of a equator of the liquid tank and opposed to be apart each other by 180°; and two belt-shaped electrodes respectively disposed in vicinities of equators of the liquid tank and the gyrosphere in a state that the follow-up electrodes are located therebetween, and opposed through the supporting liquid, wherein electricity is fed to the gyro rotor through the dish-shaped electrodes and the belt-shaped electrodes.
The gyrocompass further has a Wheatstone bridge circuit provided with: a transformer; the pair of follow-up electrodes respectively connected to both ends of a primary winding of the transformer; supporting liquid resistances respectively provided between one end of the belt-shaped electrode on a gyrosphere side and one of the pair of follow-up electrodes and between another end of the belt-shaped electrode on the gyrosphere side and another of the pair of follow-up electrodes, and whose resistance changes according to rotation of the gyrosphere; and an AC power supply provided between the belt-shaped electrode on a liquid tank side and a midpoint of the primary winding of the transformer, wherein a deviation signal induced in a secondary winding of the transformer changes according to a change in the resistance of the supporting liquid resistances.
The gyrocompass further has a Wheatstone bridge circuit provided with: the belt-shaped electrode on a gyrosphere side; the pair of follow-up electrodes; a resistance provided between the pair of follow-up electrodes; supporting liquid resistances respectively provided between one end of the belt-shaped electrode on a gyrosphere side and one of the pair of follow-up electrodes and between another end of the belt-shaped electrode on the gyrosphere side and another of the pair of follow-up electrodes, and whose resistance changes according to rotation of the gyrosphere; and an AC power supply provided between the belt-shaped electrode on a liquid tank side and a midpoint of the resistance, wherein a voltage between the pair of follow-up electrodes changes according to a change in the resistance of the supporting liquid resistances.
According to the gyrocompass, since electricity can be fed to the gyro rotor without using harmful substances such as mercury and special insulating oil or the like in the feeding route into the gyrosphere, it is possible to provide a product which is friendly to the global environment.
Further, since the Wheatstone bridge circuit can be mounted in the same way as in the conventional case, a product which ensures follow-up accuracy equivalent to conventional one can be provided without increasing the cost.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view illustrating an embodiment of a gyrocompass to which the invention is applied, an explains a feeding structure for a gyrosphere;
FIG. 2 is a perspective view illustrating as a set the electrodes on the gyrosphere side and the electrodes on the liquid tank side concerning the electrode structure of the gyrocompass in accordance with the invention;
FIG. 3 is a circuit diagram illustrating an example of a deviation detecting mechanism which is applicable to the electrode structure of the invention in the follow-up control for causing the liquid tank to follow up the gyration of the gyrosphere;
FIG. 4 is a circuit diagram illustrating another example of the deviation detecting mechanism which is applicable to the electrode structure of the invention;
FIG. 5 is a cross-sectional view illustrating a general configuration of the gyrocompass;
FIG. 6 is a perspective view illustrating a feeding structure for the gyrosphere in a conventional structure;
FIG. 7 is a cross-sectional view illustrating the details of the feeding structure through a center pin in the conventional structure; and
FIG. 8 is a diagram explaining a deviation detecting mechanism in the follow-up control for causing the liquid tank to follow up the gyration of the gyrosphere.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the invention are described with reference to the drawings. FIG. 1 is a perspective view illustrating an embodiment of a gyrocompass to which the invention is applied, and explains a feeding structure for a gyrosphere 5 . Elements identical to those of the conventional gyrocompass described with reference to FIGS. 5 to 8 will be denoted by the same reference numerals, and a description thereof will be omitted. Hereafter, a description will be given of the characteristic portions of the invention.
In the conventional art ( FIGS. 6 and 7 ), the structure provided is such that a center pin 8 supports a gyrosphere 5 , electricity is fed to a gyro rotor by mercury disposed at a tip of this center pin and the dish-shaped electrode in the lower portion, and separate follow-up electrodes are provided.
In the embodiment, the center pin 8 solely functions to only support the gyrosphere 5 . A belt-shaped electrode 200 on the gyrosphere side disposed through the supporting liquid in face-to-face relation to a belt-shaped electrode 100 provided on an outer periphery in the vicinity of the equator of the gyrosphere 5 is caused to function as one feeding route of an external power supply 10 . The other feeding route of the external power supply 10 is the same as the conventional one, and two dish-shaped electrodes 9 respectively disposed at lower portions of the gyrosphere and the liquid tank in face-to-face relation to each other are used.
In cooperation with a pair of follow-up electrodes on a liquid tank side (not shown in FIG. 1 ), the belt-shaped electrode 100 on the gyrosphere side forms a Wheatstone bridge circuit, and the structure of serving as both the electrode for feeding and the electrode for follow-up control constitutes the characteristic of the invention. By virtue of this structure, harmful substances such as mercury and insulating oil provided at the tip portion of the conventional center pin become unnecessary.
FIG. 2 is a perspective view illustrating as a set the electrodes on the gyrosphere 5 side and the electrodes on the liquid tank 4 side concerning the electrode structure of the gyrocompass in accordance with the invention. Numerical values of angles given in the drawing are given by way of example. Since the respective electrodes are given new appellations, they will be described below.
The belt-shaped electrode 100 on the gyrosphere 5 side consists of one central belt-shaped electrode 101 and a pair of two-rowed electrodes 102 and 103 . The central belt-shaped electrode 101 is disposed in the vicinity of the equator on the side surface of the gyrosphere with a predetermined width in the latitudinal direction and with a length extending slightly less than about half around the gyrosphere (its end point being 2° short in terms of the angle in the drawing) between the positions of follow-up electrodes 17 a and 17 b on the liquid tank side.
The two-rowed electrodes 102 and 103 are formed on an outer peripheral surface opposite to the central belt-shaped electrode 101 in such a manner as to be spaced apart a predetermined distance with the equator located therebetween on the side surface of the gyrosphere and with a length extending slightly less than about half around the gyrosphere (their end points being 20° short in terms of the angle in the drawing).
The belt-shaped electrode 200 on the inner wall surface of the liquid tank consists of a total of four two-rowed electrodes including a pair of two-rowed electrodes 201 and 202 and a pair of two-rowed electrodes 203 and 204 . The two-rowed electrodes 201 and 202 are disposed on the inner wall surface of the liquid tank in such a manner as to be arranged in face-to-face relation to the central belt-shaped electrode 101 on the gyrosphere side while keeping a predetermined distance therebetween in the latitudinal direction and with a length extending slightly less than about half around the inner wall of the liquid tank (their end points being 23° short in terms of the angle in the drawing).
The two-rowed electrodes 203 and 204 are formed on the inner wall surface of the liquid tank opposite to the two-rowed electrodes 201 and 202 , have a length extending slightly less than about half around the inner wall of the liquid tank (their end points being 23° short in terms of the angle in the drawing), and are arranged in close proximity to and in face-to-face relation to the two-rowed electrodes 102 and 103 on the gyrosphere side through the supporting liquid.
The dish-shaped electrode 10 is formed at the lower portion of the liquid tank 4 and the lower portion of the gyrosphere 5 , and is disposed at a position where it is located in close proximity and in face-to-face relation thereto through the a supporting liquid 6 .
By virtue of the above-described electrode structure, the mutually opposing belt-shaped electrodes (the central belt-shaped electrode 101 on the gyrosphere and the two-rowed electrodes 201 and 202 on the liquid tank) are capable of assuming large areas in the vicinity of the equator, and are therefore capable of feeding a sufficient current for driving a gyro rotor 7 if the supporting liquid (electrolyte) is present in the gap.
In addition, since supporting liquid resistors Ra and Rb between both ends of the central belt-shaped electrode 101 and the follow-up electrodes 17 a and 17 b on the liquid tank side are formed into a Wheatstone bridge, follow-up control of the liquid tank with respect to the gyration of the gyrosphere becomes possible as in the conventional case.
FIG. 3 is a circuit diagram illustrating an example of a deviation detecting mechanism which is applicable to the electrode structure of the invention in the follow-up control for causing the liquid tank 4 to follow up the gyration of the gyrosphere 5 . The circuit in which the follow-up electrodes 17 a and 17 b are connected to both ends of a primary winding of a transformer 19 is similar to the conventional circuit shown in FIG. 8 , but differs in that one side of the external power supply 10 is not a dish-shaped electrode as in the conventional circuit but is connected to the two-rowed electrodes 201 and 202 on the liquid tank side.
In FIG. 3 , the arrangement of the respective electrodes corresponds to a case in which a cross-sectional view of the liquid tank unit is viewed from above. The two-rowed electrodes 201 and 202 on the liquid tank side and the central belt-shaped electrode 101 on the gyrosphere side are opposed to each other with a relatively large area, and the electrolyte resistance therebetween is either small or of such a magnitude as to be negligible in the operation of the follow-up circuit.
In addition, the two-rowed electrodes 201 and 202 have a smaller spread (angle) than the central belt-shaped electrode 101 . The supporting liquid resistors Ra and Rb which are present between the ends of the central belt-shaped electrode 101 and the follow-up electrodes 17 a and 17 b on the liquid tank side function as bridge resistors and form a complete Wheatstone bridge together with the transformer having a center tap in the drawing.
In the above-described configuration, in a case where the gyrosphere 5 has gyrated (rotated) in the direction of arrow P, one follow-up electrode 17 a and one end of the central belt-shaped electrode 101 approach each other, while the other follow-up electrode 17 b and the other end of the central belt-shaped electrode 101 move away from each other. Therefore, the supporting liquid resistors Ra and Rb which are present in the gap mutually change differentially, so that the Wheatstone bridge is set in a state of imbalance.
As for a deviation signal E obtained by amplifying the signal from the Wheatstone bridge induced in a secondary winding of the transformer 19 as a result of this imbalance, its amplitude serves as a deviation angle, and its phase indicates the direction of gyration. It should be noted that the belt-shaped electrodes on the gyrosphere side are provided with different shapes concerning the central belt-shaped electrode 101 and the two-rowed electrodes 102 and 103 is in consideration of ensuring that the follow-up point will not be formed at a 180° inverted point.
FIG. 4 is a circuit diagram illustrating another example of the deviation detecting mechanism which is applicable to the electrode structure of the invention in the follow-up control for causing the liquid tank 4 to follow up the gyration of the gyrosphere 5 . In this example, instead of the transformer 19 for forming the Wheatstone bridge, a series circuit of resistors 22 and 23 whose values are equal is connected between the follow-up electrodes 17 a and 17 b , the other terminal of the external power supply 10 is connected to a point of connection of the resistors, and an unbalanced voltage of the bridge occurring between the follow-up electrodes 17 a and 17 b is led to an amplifier 21 to obtain the deviation signal E.
The reason two pairs of two-rowed electrodes, i.e., a total of four electrodes, are used on the liquid tank side is to symmetrically surround the peripheries of the follow-up electrodes 17 a and 17 b with the same potential so as to convert the noise due to the supply current straying in the supporting liquid into common-mode noise, thereby enhancing the follow-up sensitivity.
The follow-up technique based on the Wheatstone bridge using the follow-up electrodes and the belt-shaped electrodes used conventionally and described in the embodiment is a known technique which has been in use for a long time. The gyrocompass in the embodiment is friendly to the earth by eliminating harmful substances by allowing the belt-shaped electrodes to also serve as the feeding path for the gyro rotor, in addition to the use of the known technique of the above-described belt-shaped electrodes. | A gyrocompass has a liquid tank containing a supporting liquid therein, a gyrosphere floating in the liquid tank by the supporting liquid and whose central portion is rotatably supported by a center pin provided in an upper portion of the liquid tank, a gyro rotor incorporated in the gyrosphere, two dish-shaped electrodes disposed at a lower portion of the liquid tank and a lower portion of the gyrosphere, and opposed through the supporting liquid, and a pair of follow-up electrodes disposed in a vicinity of a equator of the liquid tank and opposed to be apart by 180°, and two belt-shaped electrodes disposed in vicinities of equators of the liquid tank and the gyrosphere in a state that the follow-up electrodes are located therebetween, and opposed through the supporting liquid, wherein electricity is fed to the gyro rotor through the dish-shaped electrodes and the belt-shaped electrodes. | 6 |
[0001] This application is a Divisional of U.S. patent application Ser. No. 09/994,840, filed Nov. 28, 2001, which claims priority to Korean Patent Application No. 71284/2000, filed Nov. 28, 2000. The entire disclosure of the prior application is considered as being part of the disclosure of the accompanying application and is hereby incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to an apparatus and method for lengthening a life span of a battery power supply in a portable appliance, and more particularly to improved power management.
[0004] 2. Background of the Related Art
[0005] Many efforts have been made to develop multimedia and personal/notebook computers having various new functions. Such development has generally added new devices, increasing the total power consumption of the system. Many portable systems are optionally powered by batteries. Because power management of the new devices is inadequate in the related art, however, the life span of batteries powering such systems has been significantly reduced.
[0006] [0006]FIG. 1 illustrates a block diagram of a power supply of a notebook computer according to the related art. In FIG. 1, a power supply of a notebook computer includes a DC (direct current) power supply output unit 11 outputting DC voltage V_DC supplied by either a battery source 15 or an AC source 16 and a AC/DC converter (not shown), a CPU(central processing unit) DC/DC converter 12 supplying a DC voltage required for driving a CPU 12 A by converting a DC voltage V_DC outputted from the DC power supply output unit 11 ; a main DC/DC converter 13 supplying DC voltages required for driving devices 13 A to 13 N respectively by converting the DC voltage V_DC, and an LCD inverter 14 supplying an LCD driving voltage by converting the DC voltage V_DC.
[0007] When being supplied with an AC source 16 , the DC power supply output unit 11 converts the AC source voltage into the DC voltage V_DC at a predetermined level and outputs the converted DC voltage V_DC. When the AC source 16 is disconnected, the DC power supply output unit 11 outputs the DC voltage V_DC from the battery 15 .
[0008] The CPU DC/DC converter 12 (i.e., transformer) converts the DC voltage V_DC outputted from the DC power supply output unit 11 into a DC voltage required for driving the CPU 12 A and outputs the converted DC voltage. The main DC/DC converter 13 converts the DC voltage outputted from the DC power supply output unit 11 into DC voltages required for driving the respective devices 13 A to 13 N installed in or connected to the notebook computer and outputs the converted DC voltages. The LCD inverter 14 generates a voltage required for the LCD by converting the DC voltage V_DC. As shown in FIG. 1, the related art power supply apparatus does not include an additional power supply management apparatus.
[0009] [0009]FIG. 2 illustrates a data entry table on a window screen according to the related art, where the power supply apparatus fails to have an additional power supply management apparatus for power saving but has a function of warning a user regarding the remaining capacity of a battery supply. As shown in FIG. 2, set up item 21 establishes whether a first alarm is outputted when the remaining capacity of the battery supply reaches a first predetermined level. A warning message of a shortage of the remaining capacity of the battery supply or an alarming sound is outputted on the basis of the set-up item 21 when the remaining capacity reaches the first predetermined level set up by the user. Another set-up item 22 as shown in FIG. 2 establishes whether a second alarm is outputted when the remaining capacity of the battery supply becomes below a second predetermined level. A warning message that a system power supply should be turned off immediately or an alarming sound is outputted on the basis of the set-up item 22 when the remaining battery capacity reaches the second predetermined level set up by the user. The battery alarm is not an effective power supply management technique. Instead, the battery alarm merely informs a user of the remaining capacity of the battery or stores the present status.
[0010] ACPI (Advanced Configuration and Power Interface) is an open industry standard for APM (Advanced Power Management) in the related art. With ACPI, power is reduced when a PC (Personal Computer) is not operated. A system supporting ACPI checks activity of peripheral devices through the OS (operating system) to optimize power consumption status for ACPI compatible devices. However, APM fails to meet the user's needs for active power supply management of peripheral devices attached to a PC that are not ACPI compatible. For instance, APM fails to consider compatibility of various communication tools that will be available for PCs in the near future.
[0011] Thus, systems in the related art are not sufficiently equipped with power supply management functions that can extend an operation time of a battery supply.
[0012] The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.
SUMMARY OF THE INVENTION
[0013] An object of the invention is to solve at least the above problems and/or disadvantages and to provide at least the advantages described hereinafter.
[0014] Another object of the present invention is to provide a power saving apparatus in a portable appliance and power saving method thereof by proposing methods to a user for saving a present battery power supply when a remaining capacity of the battery power supply in a portable appliance such as a notebook computer becomes below a predetermined level.
[0015] Another object of the present invention is to provide a power saving apparatus in a portable appliance and power saving method thereof that interrupts power supply to less critical or user-sorted devices consuming power in the portable appliance.
[0016] Another object of the present invention is to provide a power saving apparatus in a portable appliance and power saving method thereof that reduces a total power consumption of the portable appliance by disconnecting a power supply to certain devices according to a scheme selected or predetermined by a user.
[0017] In order to achieve at least the above objects in whole or in part in accordance with the purposes of the invention, as embodied and broadly described herein, there is provided a power saving method in an appliance including inputting power management data into a user set up menu on a display in the appliance, outputting a control command to a micro-controller in accordance with the power management data, and executing the power control command of the micro-controller, wherein the execution includes disconnecting battery power from a selected one of a plurality of appliance devices.
[0018] To further achieve at least the above objects in whole or in part and in accordance with the purposes of the invention, as embodied or broadly described, there is provided a power saving method in a portable appliance including checking respective systems in the portable appliance, displaying checked information for at least one of the respective systems in a user set-up menu on a screen when a remaining capacity of a battery is smaller than a first reference value set up previously by a user, outputting a control command to a micro-controller in accordance with power saving data input by a user on the user set-up menu, and executing a power saving program in accordance with the control command of the micro-controller.
[0019] To further achieve at least the above objects in whole or in part and in accordance with the purposes of the invention, as embodied and broadly described, there is provided a power saving apparatus in an appliance including a DC power supply output unit that outputs a DC voltage of a predetermined level by converting an AC power supply or by converting a battery voltage, a main DC/DC converter that supplies a plurality of operating voltages to a corresponding plurality of devices by converting the DC voltage, and a plurality of power switches that selectively disconnect each of the plurality of devices selected by a user in order to carry out a power saving function, wherein the plurality of switches are controlled by a micro-controller.
[0020] To further achieve at least the above objects in whole or in part and in accordance with the purposes of the invention, as embodied and broadly described, there is provided a power saving method in a portable appliance including a first step of displaying a user set-up menu for a power saving on a screen by checking respective systems in the portable appliance, a second step of outputting a control command to a micro-controller in accordance with power saving contents set up by a user on the user set-up menu, and a third step of executing a power saving program set up by the user in accordance with the control command of the micro-controller.
[0021] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The invention will be described in detail with reference to the following drawings in which like reference numerals refer to like elements wherein:
[0023] [0023]FIG. 1 illustrates a block diagram of a power supply of a notebook computer according to the related art;
[0024] [0024]FIG. 2 illustrates a power supply management window screen according to the related art;
[0025] [0025]FIG. 3 illustrates a block diagram of a power supply apparatus in a computer according to a preferred embodiment of the present invention;
[0026] [0026]FIG. 4 illustrates an example of a user set-up menu according to a preferred embodiment of the present invention; and
[0027] [0027]FIG. 5 illustrates a flowchart for a power saving method of a computer according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0028] Reference will now be made in detail to preferred embodiments according to the present invention, examples of which are illustrated in the accompanying drawings.
[0029] [0029]FIG. 3 illustrates a block diagram of a preferred embodiment of a power supply apparatus in a notebook computer to which a power saving method according to the present invention can be applied. The power supply apparatus may include a DC power supply output unit 31 outputting a battery voltage or a DC voltage of a predetermined level converted from an AC power supply 37 , a CPU DC/DC converter 32 supplying a DC voltage required for a CPU 32 A by converting the DC voltage V_DC outputted from the DC power supply output unit 31 , and a main DC/DC converter 33 supplying DC voltages required for driving devices 33 A to 33 N respectively by converting the DC voltage V_DC. An LCD inverter 34 can supply an LCD with a driving voltage by converting the DC voltage V_DC, and power switches 35 A to 35 N preferably turn on/off powers of the respective devices 33 A and 33 N to carry out a power saving function under control of a micro-controller or the like.
[0030] The power supply apparatus may further include a clock generator (not shown in FIG. 3) supplying the CPU 32 A with a clock. The clock generator may adjust the clock applied to the CPU 32 A by a selection of the user. Through this adjustment, a clock-throttling rate of the CPU 32 A, which will be described later, may be varied.
[0031] In a first mode of operation, an appliance such as a notebook computer shown in FIG. 3 may supply the respective devices 33 A to 33 N with a power supply by utilizing AC power supply 37 . In the first mode, the DC power supply output unit 31 may convert the normal AC power supply 37 voltage into a DC voltage of a predetermined level and may output the converted DC voltage. The DC/DC converter 32 may convert the DC voltage V_DC, which is outputted from the DC power supply output part 31 , into a DC voltage having a level required for the CPU 32 A and may output the converted DC voltage. The main DC/DC converter 33 may convert the DC voltage V_DC into DC voltages required for driving the respective devices 33 A to 33 N installed in or connected to the notebook computer and may output the converted DC voltages. The LCD inverter 34 may generate a voltage required for the LCD by converting the DC voltage V_DC.
[0032] [0032]FIG. 3 also illustrates a power saving features for a second mode of operation of the appliance that uses battery 36 . A battery power supply mode may exist when the external AC power supply applied to the DC power supply output unit 31 is disconnected. On/off switches 35 A to 35 N are coupled to power supply terminals of devices 33 A to 33 N, respectively so that the power for driving the respective devices may be selectively turned on or off. Each of the on/off switches 35 A to 35 N may be a transistor, thyristor, IGBT (insulated gate bipolar transistor), GTO (gate turn-off) thyristor, other electronic switch or the like. Moreover, the on/off switches 35 A to 35 N may be controlled by a MICOM (microcomputer) (not shown in FIG. 3) that may be built into the appliance such as the notebook computer and controlled via software. For example, a command of the user may be transferred to the MICOM through an application device driver in the Windows environment. However, the present invention is not intended to be so limited to a microcomputer.
[0033] [0033]FIG. 4 illustrates an example of a user set-up menu according to preferred embodiments of the present invention, in which various selectable options may be provided enabling a user to perform a power supply management task related to battery operation. When the battery power supply mode is activated, an application program for Windows in a portable appliance preferably may measure the remaining capacity of battery 36 and may determine the frequency that devices 33 A to 33 N are being used. In this case, the frequency of use means how many times the respective devices are used while the user uses the portable appliance.
[0034] There are alternative methods for measuring the frequency of use. In one embodiment, the system may record the number of times that each device 33 A to 33 N is used from the moment that the user turns on the power of the portable appliance to the moment that the user turns off the power. In another embodiment, the system may record the number of minutes that each device 33 A to 33 N is used from the moment that the user turns on the power of the portable appliance to the moment that the user turns off the power. Other methods for determining frequency for use may also be used. The system may display composite frequency of use information to a user. A user may use this information, for example, to identify un-used or less-used devices that do not require power at selected battery capacity levels or modes of operation.
[0035] When it is determined that the remaining capacity of battery 36 reaches a predetermined limit (for example 50%), the application program for Windows may display a user set-up menu for power saving in the form of pop-up window shown in FIG. 4. A user may also be able to access the user set-up menu shown in FIG. 4 upon demand or periodically.
[0036] A “power-off recommendation” (e.g., device) may be presented to a user on the basis of frequency of use calculations. This means that a user may save power by turning off the power of the recommended device without causing any inconvenience or limited inconvenience in using the system. In one embodiment, a user may also select a CPU state (i.e. a clock throttle rate) and an LCD brightness level, in accordance with the remaining capacity of battery 36 .
[0037] [0037]FIG. 5 illustrates a flowchart showing a preferred embodiment of a power saving method according to the present invention. In this example, a system may be driven using internal battery 36 when external power supply 37 is disconnected.
[0038] In a mode where external power is disconnected, an application program for Windows may proceed to display a user set-up menu for power saving in the form of a pop-up window, for example as shown in FIG. 4, in step S1. In one embodiment, a user may select among “power-off recommendations” (e.g., of devices) presented to a user on the basis of frequency of use. A user may also select a CPU state (i.e. a clock throttle rate) and an LCD brightness level and an execution time or status (e.g., percentage of remaining battery capacity or none). The power-off recommendations can be selected by the user to disable connected devices (e.g., IEEE1394, IR, USB, Audio, CD-ROM, Modem or the like) to reduce a power consumption rate. The frequency of use is preferably an indication presented to the user indicating relative importance and can include how many times or how much time the respective devices are used since appliance turn-on, internal battery power selected, or a composite indication of such information. As shown in FIG. 4, the respective devices have been preferably displayed in a ranked order. In step S1, the user set-up menu for power saving can preferably be determined for execution for one, more than one (e.g., 50%, 20% or x% battery residue) or no battery capacity levels. In FIG. 5, step S1 can be performed on (user) demand, periodically or optionally. However, if step S1 is not performed, a system default level may be preset (e.g., 50%) for an Nth alarm data.
[0039] The application program for Windows may then determine in step S2, through a well-known battery capacity detector (not shown in FIG. 3), a present remaining capacity of battery 36 and the frequency of use for devices 33 A to 33 N. The application program for Windows may then determine in step S3 whether battery residue alarm (control) data exists. If no battery residue alarm data exists, the process may terminate in step S9. Otherwise, control may continue to step S4.
[0040] The application program for Windows may then determine in step S4 whether the battery residue or remaining capacity of the battery power supply is greater than an Nth limit or Nth alarm data, e.g. 50%, previously set by the user.
[0041] Where the remaining capacity of the battery power supply is larger than the user previously set-up Nth alarm data (e.g., first limit), the application program for Windows may return to step S2. Where the remaining capacity of the battery power supply is less than the user defined first limit, the application program for Windows may proceed to step S5 to display a user set-up menu for power saving such as shown in FIG. 4. Based on information from step S2, the system may recommend device(s) for power disconnect, enabling a user to achieve power savings with little or no inconvenience to the user.
[0042] In step S5, the application program for Windows may also display a corresponding menu so that the user can set the state of CPU 32 A, that is, a clock throttling rate (which represents a relative numeral value of processing speed) of CPU 32 A and a brightness level of the LCD. Where a user wishes to minimize power consumption, the user may select all recommended devices for power disconnect, and may further adjust the clock throttling rate of CPU 32 A and the brightness of the LCD to minimum levels.
[0043] If the user selects the recommended device(s), a list of selected devices may be transmitted (e.g., to a micro-controller (not shown)) as a code in step S6. The micro-controller may receive the code corresponding to the devices and may then output a disable signal (e.g., a switch-off signal) to the respective switches (e.g., 35 A to 35 N in FIG. 3), thereby turning off the corresponding device(s) in step S7.
[0044] Where a user has selected changes to the CPU state and/or LCD brightness, a control command may be transmitted to the micro-controller in step S6 in order to control the clock throttling rate of CPU 32 A, the brightness of the LCD, and other power saving contents. Thus, the settings of step S6 may be executed in step S7.
[0045] The application program for Windows may then determine in step S8 an incremented value for N, which is preferably used to determine whether additional battery residue alarm (control) data exists in step S3, and the process may again return to step S2 to monitor battery capacity and frequency of device use.
[0046] In one embodiment, a user may predetermine two alarm (control) data limits being a first limit at 50% and a second limit, e.g. 20%, for power management. In this case, the process may sequentially determine in step S4 whether the remaining battery capacity has dropped below the first and then second limit. If it has, a user may select power management functions in step S5 for execution in step S7 before the process ends.
[0047] As described above, preferred embodiments according to the present invention provide methods for conserving battery power where the remaining capacity of the battery power supply in a portable appliance such as a notebook computer is reduced below one or more prescribed levels or values. Preferably, a user is guided to select less-used devices to reduce power consumption at prescribed levels. Accordingly, preferred embodiments according to the present invention enable a user to increase or maximize battery life, while reducing or minimizing functional inconvenience.
[0048] The foregoing embodiments and advantages are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. | Disclosed a system and method of lengthening a life span of a battery power supply in an appliance such as a portable appliance, notebook computer or the like. A power saving method in an appliance includes displaying a user set-up menu for a power saving on a screen by respectively checking systems in the appliance, outputting a control command to a micro-controller in accordance with power saving contents determined on the user set-up menu by a user, and executing a power saving program set up by the user in accordance with the control command of the micro-controller. | 8 |
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