description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
|---|---|---|
BACKGROUND OF THE INVENTION
A. Field of the Invention
The present invention is related to methods for manufacturing coils and more particularly to a method for manufacturing coils in which a layer of paper covered with a thermo curable resin is applied between conductors and uniformly thermoset and thermo-cured with the resultant heat produced by applying a constant density electric current to all the conductor portions of the coil—Joule effect—while an axial pressure is applied to it.
B. Description of Related Art
In processes for manufacturing coils, there are usually applied methods of compacting conductors and methods for increasing the rigidity of the coil in order to increase its tolerance to short-circuit mechanical forces and thus avoiding problems related to impedance variations of the final product.
The method of compacting conductors by any means, allows the manufacturing of smaller core-coil units, and the use of lower cost smaller oil containers.
In order to help to maintain the integrity and rigidity of the coil and additionally to electrically isolate each conductor layer, the conductors are impregnated with a non-conductive resin before compacting the coil, and subsequently the resin is heat cured inside an oven.
A method for manufacturing coils is claimed in the Japanese patent No. JP2-040902 of Ogawa et al. wherein an impregnated resin is thermoset by Joule heat while being pressurized in the coil axial direction.
In Ogawa's patent, it is disclosed that the Joule effect only produces a partial heating of the coil periphery in order to thermoset the resin, and uses a contraction magnetic force produced by the electric current through the conductors for compressing the coil in an axial direction.
Since Ogawa's method only achieves the heating of the periphery of the coil, the resin impregnated in the conductors near the core of the coil is not uniformly thermoset and thermo cured.
In order to achieve an uniform heating of the entire coil and thus a complete an uniform thermo curing of all the resin impregnated in the coil, applicant developed a method for manufacturing coils which achieves an uniform and complete curing of the paper impregnated with epoxy thermo curable resin placed between conductors by applying an electric current uniformly to all portions of the coil thus completely heating the coil, including the conductors near the core.
Applicant's method comprise: connecting both bobbin terminals to a variable electric source; calculating an initial amperage to be applied to the primary and secondary bobbin windings; activating the variable electric source; detecting the temperature obtained in the both windings; if the temperature is equal to the temperature defined by the curing graphic over current time, then the amperage must be maintained in order to maintain the windings temperature equal to the value predefined in the curing graphic; if the temperature is greater than the temperature defined by the curing graphic over current time, then the amperage must be decreased until the predefined temperature is achieved; if the temperature is lesser than the temperature defined by the curing graphic over current time, then the amperage must be increased until the predefined temperature is achieved; repeat the temperature detecting step until the last time value of the curing graphic is achieved; and deactivating the variable electric source until the last time value of the curing graphic is achieved.
By the method of the present invention, it is achieved the heating of all coil layers at a relatively uniform temperature thus curing the epoxy resin impregnated in all the papers placed between all conductors.
By applying adequate amperage to the coil it is achieved a reduction of time of the thermo curing cycle in comparison with conventional convection heating methods using ovens.
The method of the present invention uses the transformer effect of the coil for heating simultaneously all portions of the coil without needing ferromagnetic cores, or coils magnetically coupled with air core having different tensions.
Thanks to an optimum heat distribution in the coil achieved by the method of the present invention it is obtained an energy saving compared with conventional heating methods.
SUMMARY OF THE INVENTION
It is therefore a main object of the invention to provide a method for manufacturing coils that achieves the heating of all the coil layers at a relatively uniform temperature thus curing the epoxy resin impregnated in all the papers placed between all conductors.
It is a further object of the invention to provide a method of the above disclosed nature that by applying an adequate amperage to the coil it achieves a reduction of time of the thermo curing cycle in comparison with conventional convection heating methods using ovens.
It is another object of the invention, to provide a method of the above disclosed nature that uses the transformer effect of the coil for heating simultaneously all portions of the coil without needing ferromagnetic cores, or coils magnetically coupled with air core having different tensions.
It is still another object of the present invention, to provide a method of the above disclosed nature that achieves an optimum heat distribution in the coil thus obtaining an energy saving compared with conventional heating methods.
These and other objects and advantages of the method of the present invention will become apparent to those of ordinary skill in the art from the following description of the embodiments of the invention which will be made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing the physical interconnection between the elements related to the method of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The method of the present invention applies to compacted coils comprised by conductors and papers impregnated with a non conductive epoxy resin between conductors, which from now on will be referred to as bobbins each having two terminals located at one of the bobbin's ends.
Each bobbin type has unique characteristics, which define the voltage and amperage to be applied to the bobbin in order to maintain the temperature between predefined values for a predetermined time necessary cure the resin impregnated on the papers. Such predefined and unique temperature values over time are represented in a graphic called “curing graphic”.
The method of the present invention comprises in its most broad embodiment the steps of:
connecting both bobbin “B” terminals “T, T” to a variable electric source comprising a 30 KVA motorized auto-transformer 1 having a variable output of from 0 to 480V at 35 amp, connected to a 30 KVA dry type monophase transformer having an output of 24/48V and 650 amp maximum. calculating an initial amperage to be applied to the primary and secondary bobbin windings according to the curing graphic defined by the material and size of the conductors and to the process density and selecting the lesser calculated value so that the electric current density defined in the curing graphic is never exceed; activating the variable electric source: detecting the temperature obtained in the both windings by means of a thermocouple module coupled to each winding and connected to a lecture display, and comparing the temperature against the correspondent temperature value defined in the curing graphic in an specific time; if the temperature is equal to the temperature defined by the curing graphic over the current time, then the amperage must be maintained in order to maintain the windings temperature equal to the value predefined in the curing graphic; if the temperature is greater than the temperature defined by the curing graphic over current time, then the amperage must be decreased until the predefined temperature is achieved; if the temperature is lesser than the temperature defined by the curing graphic over current time, then the amperage must be increased until the predefined temperature is achieved; repeat the temperature detecting step until the last time value of the curing graphic is achieved; and deactivating the variable electric source until the last time value of the curing graphic is achieved;
In a most specific embodiment of the method of the present invention, said variable electric source comprises a variable motorized auto transformer connected to the input of a step down transformer having a capacity of 30 kVA, 24/48 volts and 1250 Amps for controlling the voltage and amperage to predetermined values, said step down transformer comprising a primary winding and two independent windings which comprise the secondary winding.
The variable electric source is controlled by electronic means comprising a CPU, volatile and non volatile memory means and data input and output means, connected to control means for the variable electric source.
The control means 4 for the variable electric source comprise electromechanic relays and contactors, digitally activated by miniature relays activated from data acquisition means having discrete input and outputs, and the system is complemented with modules having analogical input and outputs and thermocouple modules controlled by the CPU.
The control means perform two basic functions:
automatically perform a parallel connection of the secondary windings of the step down transformer 2 for providing a maximum amperage of 1250 Amps at 24V and 30 KVA to the bobbin to be processed “B”; automatically perform a series connection of the secondary windings of the step down transformer 2 for providing a maximum amperage of 625 Amps at 48V and 30 KVA to the bobbin to be processed “B”; said functions carried out by connecting the terminals of the beginning and end of the step down transformer 2 secondary windings to three magnetic contactors, each independently activated by the CPU.
There are included four temperature sensors 5 for the winding to be processed “B”, and an analog input module connected by an interface to the system's CPU instantly processes each sensor signal.
The CPU is continually running an algorithm resident in memory, comprising the following instruction sequence:
detecting and storing in volatile memory means the current bobbin “B” temperature as initial temperature; calculating the required voltage for raising the bobbin “B” temperature by accessing a database containing the nominal parameters of tension, dimension and conductor kind and impedance percentage of the bobbin to be processed, wherein the required voltage is obtained by computing the following formula:
Vreq=% Z * Vnom/100
Wherein
Vreg=required voltage for raising the temperature of the bobbin.
% Z=impedance percentage.
Vnom=nominal voltage of one of the bobbin windings.
If the resulting voltage is lesser than 20 Vac, it is automatically performed a parallel connection of the secondary windings of the step down transformer 2 ;
If the resulting voltage is greater than 20 Vac, it is automatically performed a series connection of the secondary windings of the step down transformer 2 ;
detecting and storing in volatile memory means the amperage obtained by the series or parallel connection of the step down transformer 2 secondary windings by an ampere meter;
If the amperage overpasses the maximum amperage permissible by the equipment, the variable electric source is disconnected and an alarm is activated;
If an open circuit condition is detected, the variable electric soured is disconnected and an alarm is activated;
detecting and storing in volatile memory means the bobbin “B” temperature and the amount of time passed since the beginning of the process and comparing both values with the temperature over time values predetermined in the curing graphic;
if the detected temperature is greater than the temperature predefined in the curing graphic, an amperage decreasing routine is activated, which comprises a plurality of amperage adjustments based on deviation percentages of the temperature with respect to the objective value so that the amperage is adjusted to a lesser value than the initial amperage value;
if the detected temperature is lesser than the temperature predefined in the curing graphic, then an amperage increasing routine is activated, which comprises detecting the current temperature and increasing the amperage by a percentage depending on the temperature percentage below the objective value;
if the detected temperature is equal to the temperature predefined in the curing graphic, then the initial amperage is automatically adjusted to a lesser value, that decreases the voltage applied to the bobbin “B” which is maintained by an indefinite period of time in accordance with the curing graphic;
repeat the detecting temperature step until the detected temperature is equal to the temperature predefined in the curing graphic, and the last time value in the curing graphic is achieved; and
disconnecting the variable electric source.
The method of the present invention may be applied to low-high and low-high-low interlaced bobbin configurations and with high tension accessories such as a double voltage changer and derivation changer. Also, the method may be applied to monophase and three-phase distribution transformers of any capacity and nominal voltages, manufactured under international norms.
The variable electric source amperage may be applied to heat one bobbin or simultaneously two bobbins, having the same design, wherein the amperage to be applied to each bobbin does not exceed half the capacity of the variable electric source. The electric current flowing trough the coil being processed, induce a force in the other magnetically coupled coil with air core, which promotes the flow of electric current trough it. When applying the method for processing two bobbins, the total amperage is equally distributed in both bobbins and by monitoring and controlling the temperature in one bobbin, it is possible to precisely know the status of the second bobbin with only one equipment applied to one of the two bobbins, which represent a time reduction of as far as 50% for bobbins having an amperage of as far as 50% the capacity of the variable electric source.
Finally it must be understood that the method for manufacturing coils of the present invention, is not limited exclusively to the above described and illustrated embodiments and that the persons having ordinary skill in the art can, with the teaching provided by this invention, make modifications to the method of the present invention, which will clearly be within the true inventive concept and scope of the invention which is claimed in the following claims. | A method for manufacturing coils which achieves an uniform and complete curing of the paper impregnated with epoxy thermo curable resin placed between conductors by applying an electric current uniformly to all portions of the coil thus completely heating the coil, including the conductors near the core. | 7 |
FIELD OF THE INVENTION
[0001] The invention relates to a family of medical device packages designed and fabricated to provide instantaneous recognition as to the source and origin of a sterilized medical device stored therein and for passively retaining said medical device and related items in a desired manually accessible location within the package.
BACKGROUND OF THE INVENTION
[0002] Containers designed for storing and transporting medical devices and surgical equipment are well known in the art. Generally, these types of containers include a container and a cover with sufficient volume to hold medical devices and components securely.
[0003] One of the general requirements for medical device containers is the need to maintain physical protection for a sterilized device package. Specifically, the primary features of most sterilized medical device packages are to provide protection and maintain sterility of the device until final delivery to an operating room.
[0004] Due at least in part to the proliferation of diverse device devices a wide variety of different medical device packages populate the inventory of many hospitals and clinics. The different packages must be stored in a readily accessible manner but currently popular so-called ergonomic (or non-prismatic) shaped packages do not easily stack together and a clinician must oftentimes physically remove a package in order to determine the features and the model of the device and/or the manufacturer of the device. In addition, once a prior art package is opened the package does not typically provide a stable platform for the package or the device itself.
[0005] There is, therefore, a need to provide apparatus and methods for safely transporting, storing, identifying source and origin of, and opening and utilizing stable, well-balanced packages containing sterilized implantable medical devices (IMDs), with features and structures that efficiently enhance the mechanical stability of one or more of the packages when stored in inventory at a clinic, in transport, and on an initial packaging site, promote ease of handling and complement implant procedure efficiency in the operating room.
SUMMARY OF THE INVENTION
[0006] The present invention relates to a family of medical device packages designed and fabricated to provide instantaneous recognition as to the source and origin of a sterilized medical device stored therein and for passively retaining said medical device and related items in a desired manually accessible location within the package. The invention provides apparatus and methods for safely transporting, storing, identifying source and origin of, opening, packing and unpacking, evenly balanced packages containing sterilized implantable medical devices (IMDs). While diverse IMDs can be securely conveyed within the inventive package, without limitation, the inventive package can be used for implantable pulse generators, implantable cardioverter-defibrillators, drug pumps, neurological, muscle and deep-brain stimulation devices, medical electrical leads, stents, and the like. The packages and methods of the invention also are designed with features and structures that efficiently enhance the mechanical stability of one or more of the packages when stored in inventory at a clinic, in transport, and on an initial packaging site, and promote ease of handling and complement implant procedure efficiency in the operating room.
[0007] In addition, the inventive packaging optionally includes package tracking features including wireless resonant antenna, g-force data logging and/or impingement of forces that exceed a predetermined threshold (e.g., using a uni- or multi-axis accelerometer or the like), optically encoded device information (e.g., universal product code), and/or automated shelf-life indicating means (e.g., a tactile, visual, and/or auditory signal or flag) that either automatically operate upon initial product release, during a given prescribed shelf-life, or following expiration of the prescribed shelf-life and/or intermittently indicates shelf-life status when the IMD package is handled or moved.
[0008] The package optionally includes apertures to enable a gradual but continuous release of sterilization gas residues and provide for equalization of pressure during, for example, a pressure excursion encountered during transit.
[0009] The apertures provide an exit for gases such as ethylene oxide, hydrogen peroxide or the like that might otherwise accumulate in the interior of the package which could render the package and the IMD unacceptable in certain jurisdictions with strict emission standards.
[0010] The package optionally includes one or more security seal members or structures that indicates that the package has been opened for the first time, thus providing visible proof if the package was tampered with, opened, or otherwise possibly compromised. One type of member includes a short segment or segments of adhesive tape (e.g., fabricated from PVC or other more environmentally friendly materials). Another type of member includes a dual purpose package wrap covering all or a portion of exposed surfaces of the package and optionally including one or decorative source-identifying symbols, logos, trademarks and the like.
[0011] While multiple embodiments of the present invention are described, depicted, and claimed herein still other embodiments of the invention will become apparent to those skilled in the art following review of the instant patent document. All such embodiments are intended to be expressly covered hereunder. Also the invention can be modified in various insubstantial ways without departing from the scope of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive wherein common elements are sometimes identified in the various views by common reference numerals and the elements depicted are not rendered to scale.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 depicts a perspective view of an opened package according to an embodiment of the present invention.
[0013] FIG. 2 depicts a perspective view of the interior of the opened package according to an embodiment of the invention.
[0014] FIG. 3 depicts a perspective view of the interior of the opened package according to an embodiment of the invention.
[0015] FIG. 4 depicts a perspective view of the opened package according to an embodiment of the invention having a pair of additional enlarged views of one form of interlocking corner engagement structures depicted alongside FIG. 4 (views D,E).
[0016] FIG. 5 is a plan view of the interior major planar surfaces of the opened package according to an embodiment of the invention.
[0017] FIG. 6 is a plan view of the exterior major planar surfaces of the opened package according to an embodiment of the invention.
[0018] FIG. 7 is an elevational view of one end of a package according to the invention and featuring an area to be enlarged for ease of review (denoted as “SEE DETAIL A”).
[0019] FIG. 8 is an elevational view of one side of a package according to the invention depicting the package in the fully opened configuration and featuring two areas to be enlarged for ease of review (denoted as “SEE DETAIL B” and “SEE DETAIL C”).
[0020] FIG. 9 is a view taken along line A-A of FIG. 5 .
[0021] FIG. 10 is enlarged area A from FIG. 7 .
[0022] FIG. 11 is enlarged area B from FIG. 8 .
[0023] FIG. 12 is enlarged area C from FIG. 8 .
[0024] FIG. 13 schematically illustrates several additional optional features of a package according to the invention; namely, impact data logging module, wireless scanner module, and printed product identification code field.
DETAILED DESCRIPTION OF THE INVENTION
[0025] FIG. 1 depicts a perspective view of the external major surfaces 110 , 112 of an opened package 100 according to an embodiment of the present invention. Major surfaces 110 , 112 are coupled to external minor surface 111 by a pair of hinges 102 , 104 . An optional set of apertures 108 are formed in minor surface 111 and provide a venting function for the interior of the package 100 . The hinges 102 , 104 are depicted as continuous linear regions having a relatively thinner cross section that the surfaces 110 , 111 , 112 although different structures can be used. However, as depicted the package 100 is formed as a unitary injection molded part the hinges 102 , 104 are formed simply as relatively thinner having beveled lateral side walls adjacent the surfaces 110 , 111 , 112 so that if one of the hinges 102 or 104 are opened to a maximum degree then the beveled lateral side walls of that portion function as a mechanically stop. The hinges 102 , 104 cooperate so that when the package 100 is opened the major surfaces 110 , 112 and the minor surface 111 are substantially coplanar and thus provides a firm foundation for the package 100 and the contents disposed therein.
[0026] On an area of the external major surface 112 preferably source-identifying indicia 106 is displayed and as depicted the indicia 106 forms an integral part of the major surface 112 (i.e., the indicia 106 is included in the mold for the package 100 and is formed during injection of resin material into the mold). One of the inventive aspects of the present invention includes the foregoing source-identifying indicia 106 and either in lieu of or in addition to indicia 106 the resin or other material used to fabricate the package 100 (or at least one externally visible portion of the package 100 ) is colored per a trade dress color, a trademark color, of the sponsor, manufacturer or other source of the articles carried within the package 100 . For example, in one embodiment of the invention the indicia 106 comprises one or more logos, trademarks or service marks owned by Medtronic, Inc. of Minneapolis, Minn., U.S.A. and the resin utilized to fabricate the package 100 is PMS code number 301 (blue) as identified by the Pantone Matching System (PMS) codes distributed by Pantone, Inc. of 590 Commerce Boulevard, Carlstadt, N.J., U.S.A. In another example the indicia comprises a logo, trademark or service mark of Vitatron B. V. a subsidiary of Medtronic, Inc. that operates with a relatively newly released source identifying trademark color for its products a green hue or hues corresponding to PMS code number 376 (primary) and/or PMS code number 382 (secondary). That is, more than one color can be utilized, as appropriate depending on the trademarks or trade dress of the person or firm who supply the devices or materials provided along with the source-identifying package 100 .
[0027] FIG. 2 depicts a perspective view of the interior of the opened package 100 according to an embodiment of the invention. Optionally, at least one aperture 108 couples the interior of the package 100 (when closed) to ambient atmosphere. As depicted the aperture 108 comprises five discrete apertures formed in minor surface 111 , although other locations can be suitably utilized. The aperture 108 allows diverse vapors from sterilization materials to escape the package 100 (even through a layer of clear heat shrink film or the like).
[0028] FIG. 3 depicts a perspective view of the interior of the opened package 100 according to an embodiment of the invention. FIG. 3 illustrates that two cooperating structures populate the interior of the package 100 ; namely, a region 118 surrounded on three sides by opposing walls 115 and end wall 114 . End wall 114 optionally includes a cut-out portion having a radius that promotes manipulation of the package 100 when opening and closing same. The device-retaining location is denoted by reference numeral 116 that is surrounded on all four sides by opposing walls 117 , wall 119 and wall 119 ′. The walls 117 , 119 , and 119 ′ are described in greater detail hereinbelow.
[0029] Also depicted in FIG. 3 are a pair of ribs 122 disposed on the interior of minor surface 111 . The ribs 122 provide a biasing force to the wall 119 ′ and can be designed to seal the opposing ends of the package 100 when in the closed configuration. The biasing force helps support the wall 119 ′ and, for appropriately-sized objects disposed in the location 116 (e.g., sterile device envelope or inner package, documentation, etc.), tends to retain same during transport and storage.
[0030] FIG. 4 depicts a perspective view of the opened package 100 according to an embodiment of the invention having a pair of additional enlarged views of one form of interior interlocking corner engagement structures 124 , 126 depicted alongside FIG. 4 (denoted as enlarged views D,E). The structures 124 , 126 provide reversible positive mechanical engagement when the package 100 is closed. Thus, the structures 124 , 126 each include an elongated raised part and an elongated recessed part and provide an appreciable (i.e., audible and/or tactile confirmation when the package 100 is firmly closed). The package 100 is designed and constructed so that when the package 100 is closed the structures 124 , 126 are not visible; in fact, other than required labeling, the exterior of package 100 in the exemplary embodiment is devoid of ornamentation (save for the trademark or trade dress color or colors of the package or portions thereof and the indicia 106 ). Of course, other forms and types of interior interlocking structures 124 , 126 can be utilized along the lines of the foregoing description, but the depicted structure lend themselves to thermoplastic injection molding. Also depicted in enlarged view E of FIG. 4 is a lower peripheral shelf 128 . Shelf 128 provides a mechanical stop to the opposing top edge of wall 114 (except for cut out region 120 ) and in conjunction with cut out region 120 provide an effective manual access location when opening the package 100 . In fact, in the depicted embodiment the area defined by region 120 and shelf 128 provide the only readily manually accessible location on the package 100 (when closed).
[0031] FIG. 5 is a plan view of the interior major planar surfaces of an opened package 100 according to an embodiment of the invention. The three-walled region 118 and four-sided region 116 are of course of comparable area and spaced apart by minor surface 111 (without the hinges 102 , 104 depicted). The ribs 122 are shown in relationship to lateral sides of minor surface 111 . An optional manufacturing code 109 is depicted as disposed on the surface 111 provides information related to the fabrication, use, dates, configuration, etc. for the package 100 . While not specifically depicted, the four walls surrounding the region 116 and/or the three walls surrounding the region 118 can be inclined slightly (from an orthogonal relationship) with a draft of approximately between one half degree and about three degrees. The magnitude of the draft can change depending on the desired relationship or mechanical friction to be encountered when closing the package 100 . Also, the amount of draft can be adjusted to decrease or eliminate the surface scratching that sometimes occurs when an injection molded part is ejected from its mold. This is important at least in the context of one exemplary embodiment of the invention in which the majority of externally visible surfaces include a fine surface finish or complexion which includes just enough texture to increase the ease of manipulation during use (including use with latex or sterilized gloves or the like). The draft can also serve to retain a sterile device package, literature or the like residing within the region 116 .
[0032] FIG. 6 is a plan view of the exterior major planar surfaces of an opened package 100 according to an embodiment of the invention. In this view of a package 100 the venting apertures 108 on surface 111 are bounded by hinges 102 , 104 . The indicia 106 (albeit inverted in FIG. 6 ) is displayed on the major surface 112 but could be displayed on major surface 110 alone or on both 110 and 112 .
[0033] FIG. 7 is an elevational view of one end of a package 100 according to the invention and featuring an area to be enlarged for ease of review (denoted as “SEE DETAIL A”) which appears as FIG. 10 herein. The shelf 128 next to interlocking structures 124 , 126 and the cut-out region 120 of the opposing side of the package 100 are also depicted in FIG. 7 .
[0034] FIG. 8 is an elevational view of one side of a package 100 according to the invention depicting the package 100 in the fully opened configuration and featuring two areas to be enlarged for ease of review (denoted as “SEE DETAIL B” and “SEE DETAIL C”), which appear as FIG. 11 and FIG. 12 herein, respectively. The configuration of walls 115 , 117 are depicted in FIG. 8 (e.g., the relative height and shapes of the upper portions of the walls 115 , 117 ).
[0035] FIG. 9 is a view taken along line A-A of FIG. 5 (i.e., the inner portion of wall 114 ). The specific nominal dimensions for an embodiment of the interlocking structure 126 are included in FIG. 9 and the relative size of the cut-out region 120 is also depicted.
[0036] FIG. 10 is enlarged area A from FIG. 7 and depicts wall 119 and interlocking structure 124 and nominal dimensions for same disposed alongside shelf 128 . Juxtaposed in the view of FIG. 10 is the wall 114 and the cooperating structure 126 disposed thereon when the package 100 is in a nearly-fully open configuration.
[0037] FIG. 11 is enlarged area B from FIG. 8 and illustrates the protruding portion of structure 124 coupled to wall 119 and also depicts the configuration or features of the upper corner of wall 117 , which is also visible in several of the other drawings. This upper corner provides mechanical strength and stability to the four walls surrounding region 116 . For example, the upper corner features provide improved alignment when the package 100 is just beginning to close, among other aspects.
[0038] FIG. 12 is enlarged area C from FIG. 8 in which the ribs 122 disposed on opposite sides of minor surface 111 in relation to walls 115 and 117 . While the ribs 122 appear rounded other shapes or cross sections can be utilized. In addition, the hinges 102 , 104 are depicted in FIG. 12 .
[0039] FIG. 13 schematically illustrates several additional optional features of a package 100 according to the invention; namely, impact data logging module 200 , wireless scanner module 300 and printed product identification code field 400 . With respect to data logging module 200 includes an accelerometer or other mechanical sensor (e.g., single- or multi-axis unit) and wireless transmitting circuitry for providing a signal to a remote unit 250 regarding temporal and/or physical impact(s) upon the package 100 and thus, the device contained therein. For example, the module 200 can measure the amount of time since the package and/or device therein have remained closed and/or the magnitude and timing of any supra-threshold (or all) physical impact forces that impinge upon the package 100 . The remote unit 250 receives the signal and provides an alert (e.g., an illuminated of flashing light 252 , a text message 254 , a trace 258 on a data log screen 256 from a sensor or the like). The unit 250 can also include memory and transmitting circuitry to communicate with a central or other tracking equipment and the like. In addition or in lieu of the foregoing, the remote unit 250 can include time stamp 260 , a nominal or calibration indicia 262 and adjustable threshold or limit 264 .
[0040] The package 100 can also include an RF or optical scanner-compliant label or similar 300 , for example, usable with a manual scanner 304 which emits optical or RF radiation 304 and contains memory and transmitting circuitry for collecting and correlating the scanned packages 100 . Such a capability improves inventory management and tracking of the package during transit, among other advantages.
[0041] The package 100 can also include printed product identification code field 400 (e.g., a UPC-type code) as is known in the art and widely supported in many fields of endeavor, including many hospitals and clinics.
[0042] While not depicted an embodiment of a self-supporting tray in which the implantable medical device may be stored. Tray is typically sterilized and may be made from foam or plastic material, including a hollow central interior portion with a flange extending thereabout for placing the medical device and other information therein. While also not specifically depicted, at least one breakaway strip can be adhered across a seam where the sides of package 100 overlap to provide a visible indication whether the package 100 has been opened (e.g., operates as a tamper-proof indicator). When the package 100 is opened a tensile force is exerted on breakaway strip that ultimately breaks to allow the package 100 to open. A broken strip serves as visible proof that package 100 has been opened and/or tampered with thus enabling the end user to reject the package 100 .
[0043] While some selected and representative embodiments have been shown in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention. | The present invention relates to a family of medical device packages designed and fabricated to provide instantaneous recognition as to the source and origin of a sterilized medical device stored therein and for passively retaining said medical device and related items in a desired manually accessible location within the package. The invention provides apparatus and methods for safely transporting, storing, identifying source and origin of, opening, packing and unpacking, evenly balanced packages containing sterilized implantable medical devices (IMDs). The packages and methods of the invention also are designed with features and structures that efficiently enhance the mechanical stability of one or more of the packages when stored in inventory at a clinic, in transport, and on an initial packaging site, and promote ease of handling and complement implant procedure efficiency in the operating room. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
Applicant claims the benefit of Provisional Patent Application No. 60/963,033 filed on Aug. 1, 2007 by the same inventors.
BACKGROUND OF THE INVENTION
1. Field of Invention
A modified shower head provides a timepiece imbedded within a shower head insert allowing a person showering to keep track of time and also to monitor water usage. It also provides the person showering with a timing mechanism to determine the length of time for use of hair products, tints, dyes and treatments without having to reference an outside timepiece. The insert comprises a timepiece within an encased water-proof enclosure.
2. Description of Prior Art
The following United States patents were discovered and are disclosed within this application for utility patent. All relate to mechanisms which incorporate timed apparatus within a shower delivery system.
Two patents describe devices that control the flow of water with a timed shutoff means. In U.S. Pat. No. 2,545,928 to Martin, the automatic water shutoff device has a timer which closes a mechanical valve after a set period of time has expired. It does not tell time, but could, since it embodies a clock face. A similar device is disclosed in U.S. Pat. No. 4,345,621 to Dunckhorst, except it is specifically adapted to a shower head having a rotary dial to set the time of water flow. It does not tell time.
Most closely similar is a combination timepiece shower head, U.S. Pat. No. 4,944,049 to Leonard, with the first several claims dealing with the aspects of the mechanical shower head with a clock within a housing. The last eight claims deal with the shower apparatus having an electronic clock, a digital clock, a display of real time in digital form, a real time/elapsed time combination display, a battery operation, and a switching means for the clock. It is basically a replacement shower head replacing the conventional shower head without a timepiece. It does not disclose the housing as related to the clock, except for a cursory mention in column 3 lines 51-68, with any specific detail, other than to state that “the clock display . . . is mounted in housing . . . and is completely sealed from water contamination.”, lines 62-64.
A simple hourglass timer which attaches to a shower wall is disclosed in U.S. Pat. No. 5,260,918. Several other patents of this nature were also discovered which provide a simple waterproof clock for use in the shower or bath. However, none of them provide any reference which would indicate same or similar elements as would be found in the present device.
SUMMARY OF THE INVENTION
Shower head have been in use for years. Typically, these shower head comprise a shower head cone with an insert for adjusting the water flow and spray patterns of the shower head. While these devices are suitable for their intended purposes, they are not suitable for the placement of an interchangeable plug with a functional clock face and a selection of decorative backgrounds. It would be desirable if the ordinary shower head would include an interchangeable functional clock and a decorative background to blend with the colors and decor of the bathroom and shower or to suit the chosen taste of the user.
In this regard, the present timepiece shower head replaces a traditional insert of a shower head with a waterproof timepiece having a selected background, serving a function of still adjusting the flow and spray pattern of the shower head, but also providing a timepiece for the user to tell time, determine the passage of time and also to set an alarm of an alert when a given amount of time has elapsed to conserve water and to prevent too much time being spent in the shower.
The primary objective of the invention is to provide a shower head having an interchangeable plug insert including a clock and a background scene or icon. A second objective is to provide the shower head with the ability to inform a user of the current time, preventing people from being late, from using too much water or for use with timed hair and hygiene treatments. A third objective is to provide the insert with a different aesthetic appearance to suit the taste of the user. A fourth objective is to provide the plug insert as a means of conserving water usage or to allot the amount of time each user spends where a large number of occupants reside within a single household. A fifth advantage lies with a parents ability to train a child to take an appropriate amount of time in the shower. Other advantages may be realized may be obvious to a user which would be obvious to those users within the scope of this improved shower head insert.
DESCRIPTION OF THE DRAWINGS
The following drawings are submitted with this utility patent application.
FIG. 1 is a representation of the prior art shower head.
FIG. 2 is a cross-sectional view of the prior art shower head.
FIG. 3 is a front view of the improved shower head with the interchangeable waterproof timepiece insert installed.
FIG. 4 is a cross sectional view of the improved shower head with the timepiece insert.
FIG. 5 is an expanded view of the components of the interchangeable waterproof timepiece insert and the shower head cone.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An improvement to shower head providing an interchangeable waterproof timepiece member 10 to replace a shower cone regulator insert 110 within a shower head cone 100 pivotally and rotatably attached to a shower pipe stem 120 emanating from a wall 130 within a shower or bath, FIGS. 1-2 , the improvement, shown in FIGS. 4-5 , comprising the interchangeable waterproof timepiece member 10 defining a shower piece insert 20 having an externally threaded nipple 23 on a rear surface 22 inserted into an internally threaded female receiver 102 within the shower head cone 100 , the shower piece insert 20 further defining an outer perimeter elevation 24 having an O-ring groove 25 for the insertion of an O-ring 30 and a front surface 26 defining an externally threaded rim 27 and an inner cavity 28 , the inner cavity 28 containing a sealed timepiece 40 with an ornamental background 44 , a rubber seal washer 60 maintaining a waterproof compression seal between the sealed timepiece 40 and the inner cavity 28 and an internally threaded outer seal ring 70 having an open timepiece display orifice 72 , retaining an outer portion 42 of the sealed timepiece 40 within the inner cavity 28 . The sealed timepiece 40 further comprises a clock face 41 , either digital or analog, an inner chamber 43 wherein a low voltage power supply 45 operates a clockwork assembly 46 and a waterproof seal cap 48 on a rear portion 47 of the sealed timepiece 40 forming a watertight seal to the sealed timepiece 40 .
The externally threaded nipple 23 of the shower piece insert 20 , being easily removed from the internally threaded female receiver 102 of the shower cone 100 , allows for the removal of the interchangeable waterproof timepiece member 10 to gain access to and change the sealed timepiece 40 or open the waterproof seal cap 48 to gain access to the clockwork assembly 46 to change the time or the change the low voltage power supply 45 when spent. In other embodiments, the externally threaded nipple 23 may be replaced by another form or generic connecting means that would allow the shower piece insert to be connected within the shower cone as a substitute for the existing cone regulator insert 110 . However, the other structures would remain consistent.
The interchangeable waterproof timepiece member 10 may be made from many selected materials, but it would be best if the shower piece insert 20 was made of a similar material or a durable metal or plastic as the shower cone regulator insert 110 being replaced, rigid and non-deformable, especially since the interchangeable waterproof timepiece member 10 would be under pressure from the water. The O-ring 30 would preferably be a flexible rubber, compressible to form a tight seal between the shower piece insert 20 and the shower head cone 100 to allow a controlled flow similar to the shower cone regulator insert 110 being replace to maintain the function of the original shower head. The rubber seal washer 60 should also tightly conform to the sealed timepiece 40 and be deformable allowing the sealed timepiece 40 to be compressed within the inner cavity 28 and retained without movement once the internally threaded outer seal ring 70 is applied to the externally threaded rim 27 of the shower piece insert 20 . The internally threaded outer seal ring 70 may be made of metal, plastic or other non-deformable rigid material with a finish to complement the shower head cone 100 and the sealed timepiece 40 framed within the timepiece display orifice 72 .
The sealed timepiece 40 may also provide an alarm which may be set for a chosen length of time, a mode selection button to select between real time and a timed chronometer, and a switch to activate and deactivate the alarm setting and to set the clock for use in the user's time zone location, if it would be more convenient to leave the sealed timepiece in the inner cavity to change the timepiece settings. The alarm may be provided by a buzz or a small audio loop which would be programmed into a timepiece sound module, which may be related to the ornamental background 44 . By example, if the ornamental background 44 were a sports insignia, the alarm may be provided as a sound loop for that particular team song. As another example, although not suggesting use without the appropriate license, if a cartoon character were provided in the ornamental background 44 , a song associated with that cartoon character might be appropriate. Although not necessarily shown in the drawings, these timepiece features already exist in the prior art and are not within themselves novel, but may be incorporated within the sealed timepiece 40 .
The sealed timepiece 40 may also include as an accessory, not shown but contemplated within the scope of this shower head insert where new technologies may apply, a video screen or a small radio. It is also contemplated that a recharging means, not shown, may also be included using the water flow associated with the shower head, to recharge the internal low voltage power supply 45 , with a type of water wheel generation system.
While the improvement has been particularly shown and described with reference to a preferred embodiment 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 disclosed interchangeable waterproof timepiece member 10 . Further, the foregoing disclosure is considered illustrative only of the principles of a shower piece insert 20 and may be modified to suit other shower heads of any shape or form. The shower head insert 20 may be presented in a form which would replace the cone regulator insert 110 in any shower head and thus define any connecting structures or connecting means 23 that would allow for the improvement to be substituted for the currently manufactured shower cone insert 100 . Further, since numerous modifications and changes will occur with those skilled in the art, if is not the intent of this disclosure to limit the improvement to the exact construction and operation shown a described. Thus and accordingly, all suitable modifications and improvements resorted to may be considered within the scope of this improvement to any conventional shower head. | A modified shower head provides a timepiece imbedded within a shower head insert allowing a person showering to keep track of time and also to monitor water usage. It also provides the person showering with a timing mechanism to determine the length of time for use of hair products, tints, dyes and treatments without having to reference an outside timepiece. The insert comprises a timepiece within an encased water-proof enclosure within the shower head insert. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a yarn cutting device in a twister.
When a plurality of yarns are twisted together in a twisting frame, even if one of them is broken, an abnormally twisted yarn is taken up. In order to avoid this undesirable situation, it has been proposed to cut the abnormally twisted yarn on the winding side simultaneously with the yarn breakage as described above. This method, however, causes such as inconvenience that an end portion of yarn produced by the yarn breakage or the cutting twines itself round a spindle or the like of the twisting frame.
SUMMARY OF THE INVENTION
The present invention relates to a yarn cutting device in a twister, and more particularly, relates to a device for cutting fed yarns at a suitable position in quick response to the breakage of the yarn when a plurality of yarns are arranged and twisted together in a twisting frame.
An object of the present invention is to provide a cutting device in which fed yarns are cut simultaneously with the occurrence of a yarn breakage and cut yarn ends do not twine itself on the twisting frame.
The device of the present invention comprises a yarn breakage detecting device for detecting a change in the tension on the twisted yarn, a first cutter which is operated by the detecting device and cuts the second yarn component on the yarn feeding side of the twisting frame, and a second cutter which is operated by the detecting device and cuts the first yarn component on the yarn taking-up side of the twisting frame.
In accordance with the present invention, the fed yarn is cut simultaneously with the occurrence of a yarn breakage. As a result, such a situation does not arise that a defective yarn is wound on the package in some length. Further, when a yarn is broken, it will not twine itself on the spindle or other parts, thus dispending with a cumbersome operation.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic representation of a two for one twister; and
FIG. 2 shows the peripheral portion of the yarn breakage detecting device shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
One illustrative example of the invention is hereinafter described with reference to the drawings.
FIG. 1 is a schematic representation of the whole construction of a two for one twisting machine, in which a package of a first yarn component (Pa) is installed in a two for one twister 1. A first yarn component (Ya) taken out from the package (Pa) is passed from the upper end of a tenser 2 to the center of a yarn storage table 3 through a yarn passing hole (not shown). Then, the yarn passes through another yarn passing hole made radially in the storage table. Thereafter, it is drawn out through a yarn guide hole 4.
Supported below the two for one twister 1 is a package of a second yarn component (Pb) mounted on a peg 5. A second yarn component (Yb) taken out from the package (Pb) is introduced into a supporting pipe 9 supporting the frame 1 via a guide roller 7 and a guide ring 8. The yarn is then brought out through a yarn guide hole 12 after being passed through a spindle 11 and a yarn passing hole formed in the storage disk 3.
The first yarn component (Ya) and the second yarn component (Yb) brought out as described above are pulled upward while ballooning out as indicated by Ba and Bb, respectively. Then, the yarns are arranged together at a balloon guide ring 13 and then twisted together to produce a twisted yarn (Yc), which then passes by a yarn breakage detecting device 14 and a feed roller 15 and reaches a traverser 16. There, a reciprocating motion is given to the yarn, and it is wound on a take-up package (Pc).
The operation of the twister 1 is well known in the prior art. That is, the spindle 11 engages with a running belt 17 and hence is caused to turn. This rotates the yarn storage table 3 together with a turntable 18. At the same time, the first yarn component (Ya) is drawn out to effect twisting operation while the package (Pa) is held stationary. At the same time, the second yarn component (Yb) is drawn out in the present twister.
The details of the yarn breakage detecting device 14 are shown in FIG. 2, in which the device 14 comprises a rocking plate 22 and a sensor 24, which acts to detect the leg 23 extending from the plate 22. The rocking plate 22 is rotatably mounted to a shaft 21 in a bracket 19 that is fixed to a frame (not shown). The plate 22 includes an arm 26, from which a balance weight 25 depends, and a pin 29 which is in contact with the twisted yarn (Yc) between guide rollers 27, 28 secured to the bracket 19. The weight of the balance weight 25 urges the arm 22 to rotate in the counterclockwise direction as viewed in the drawing, thus pressing the pin 29 against the yarn (Yc).
When one or both of the first yarn component (Ya) and the second yarn component (Yb) are broken for one cause or another during twisting operation, the tension on the twisted yarn (Yc) between the guide rollers 27 and 28 decreases abruptly. This rotates the rocking plate 22 about the shaft 21, moving the leg 23 away from the sensor 24. Thus, the sensor 24 having a photoelectric structure detects the occurrence of the yarn breakage and operates cutters 31 and 32.
The first cutter 31 is disposed between the guide ring 8 and the supporting pipe 9 which supports the twister 1, and the cutter surrounds the yarn path of a running second yarn component (Yb). As soon as a yarn breakage is detected by the detecting device 14, the first cutter mechanically and momentarily cuts the second yarn component (Yb) with blades (not shown). It is obvious that if the yarn breakage occurs below the first cutter 31, that is, the second yarn component (Yb) is broken, the cutter 31 cuts the air rather than a yarn. The second cutter 32 is disposed between the balloon guide ring 13 and the detecting device 14 and is fixed to the bracket 18. Although the second cutter is similar in structure and operation to the first cutter 31, a timer, a delay circuit, or the like functions to operate the second cutter later than the first cutter 31 by 0.5 to 3.0 seconds. At this time, the first yarn component (Ya) or the second yarn component (Yb) in the second cutter 32 is cut.
A bracket 33 supports the balloon guide ring 13, and a presser foot 36 is rotatably secured to the bracket by a shaft 37. The presser foot 36 has a feeler 34 and a drop wire 35. The tip of the feeler 34 is caused to lightly contact the twisted yarn (Yc), so that the feeler is prevented from rotating. When the second cutter 32 cuts a yarn, any yarn ceases to exist at the contact position, whereby the feeler is unlocked. The presser foot 36 then rotates in the counterclockwise direction as viewed in the drawing by its own weight until the drop wire 35 abuts against the top of the tenser 2 and stops as indicated by the phantome lines in FIG. 2. At this time, the tip of the drop wire presses the first yarn component (Ya) so that the yarn (Ya) is no longer taken out from the package (Pa).
When the first yarn component (Ya) or the second yarn component (Yb) is broken in the aforementioned twister during twisting operation, the yarn breakage detecting device 14 detects it simultaneously with its occurrence and operates the first cutter 31 and the second cutter 32 to cut the first yarn component (Ya) and the second yarn component (Yb).
In case where the first yarn component (Ya) is broken, the first cutter 31 is operated to cut the running second yarn component (Yb). Then, after a lapse of 0.5 to 3.0 seconds, the second cutter 32 is operated. The piece of the yarn which is produced on the first yarn component (Ya) winding side by the yarn breakage passes across the second cutter 32 during a period beginning with the occurrence of the yarn breakage and ending with the actuation of the second cutter 32. At this time, the piece of the yarn which is produced on the second yarn component (Yb) winding side by the cutting using the first cutter 31 is pulled upward close to the second cutter 32.
Consequently, the second cutter 32 cuts only the second yarn component (Yb). The piece of the yarn produced by the cutting is relatively short, and falls near the twister or is blown off. If the end of the second yarn component (Yb) on the winding side has already passed across the second cutter 32 when the cutter 32 is set into motion, then it cuts the air and no piece of yarn is cut off.
In case where the second yarn component (Yb) is broken, the first cutter 31 cuts either the air or the second yarn component (Yb), depending on whether the breakage takes place below or above the cutter 31. The piece of the yarn cut off by the breakage and the cutting falls in the same manner as the foregoing. When the second cutter 32 begins to operate, the end of the second yarn component (Yb) on the winding side has already passed across the cutter 32, and therefore the cutter 32 cuts only the first yarn component (Ya).
When any yarn ceases to exist between the second cutter 32 and the balloon guide ring 13 by the cutting operation of the second cutter, the presser foot 36 is rotated to prevent further supply of the first yarn component (Ya) as described above. Up to this time, the second yarn component (Yb) ceases to exist in the two for one twister 1 as described previously, whether the first yarn component (Ya) or the second yarn component (Yb) is broken. However, a length of the second yarn component (Yb) on the supply side is left, and this whirled by the rotation of the yarn storage table 3.
If the second yarn component (Yb) is left in the two for one twister 1, the piece of the first yarn component (Ya) on the supply side may twine itself round the left under yarn thus to hinder the piece of the middle yarn from whirling as described above. In the present two for one twister, however, the piece of the yarn is whirled unimpeded as stated above. Further, the stoppage of the supply of the yarn causes an increase in the tension with the result that the piece of the first yarn component (Ya) on the supply side is cut by a larger length near the yarn guide hole 4. Finally, both pieces of the yarns are cut and hence no yarn twines itself on the spindle 11 and other elements.
It is also possible to operate the first cutter 31 and the second cutter 32 simultaneously. Further, this simultaneous operation may be started slightly later than the detection of a yarn breakage. In this case, a piece of a yarn, which is cut off and falls, tends to have a larger length and so this is uneconomical. In addition, it is possible that the piece of yarn twines itself about other mechanical parts. Consequently, it is preferred that the delay be appropriately adjusted in association with the velocity of the yarns or other factors. Furthermore, the presser foot 36 may be omitted without introducing difficulties, depending on the kind of yarn or other factors. Additionally, the cutting device according to the invnetion is not limited to two for one twisters and may also be applied with equal utility to single twister and the like. | A device for cutting fed yarns at a suitable position in quick response to the breakage of the yarn when a plurality of yarns are arranged and twisted together in a twisting frame. A first cutter which is operated by a detecting device and cuts the yarn on the yarn feeding side and a second cutter which is operated by the detecting device and cuts the yarn on the yarn taking out side of the twisting frame. | 3 |
This is a continuation of copending application Ser. No. 800,226, filed on Nov. 29, 1991, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to a method of manufacturing a light-emitting electronic device and to devices produced by the method.
SUMMARY OF THE INVENTION
According to the invention a method of manufacturing a light-emitting electronic device includes the steps of:
providing a substrate of transparent intrinsic diamond material;
implanting p-type ions into the substrate to define a first p-type region in the substrate;
depositing a first transparent layer of diamond material over the p-type region;
forming at least one transparent conductive contact on or adjacent to the first transparent layer; and
applying a conductive contact to the first p-type region.
The first transparent layer is preferably deposited by a chemical vapour deposition (CVD) process, and preferably is grown as a single crystal on the substrate.
The first transparent layer may comprise a single region, or may comprise two or more discrete regions of different material.
For example, the first transparent layer may include a region of lightly p-doped diamond, a region of intrinsic diamond, and a region of high growth rate plasma jet-grown diamond, the different regions being separated by insulating material.
Where the first transparent layer comprises two or more discrete regions, a corresponding number of respective transparent conductive contacts may be formed on or adjacent to each region, so that two or more independently controllable light emitting structures are formed in a single substrate.
The transparent conductive contacts may comprise indium tin oxide, for example.
Further according to the invention there is provided a light emitting device comprising:
a substrate of transparent intrinsic diamond material having a p-type region formed therein;
a first transparent layer of diamond material deposited over the p-type region;
at least one transparent conductive contact on or adjacent to the first transparent layer; and
a conductive contact applied to the first p-type region.
The invention extends to voltage indicating devices and to light sensitive logic devices incorporating the light emitting electronic devices.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic sectional view of a first embodiment of a light-emitting electronic device according to the invention;
FIG. 2 is a schematic sectional view of an optical logic device incorporating a number of light emitting devices according to the invention;
FIGS. 3, 4 and 5 are equivalent circuits of the device of FIG. 2;
FIG. 6 is a schematic sectional view of a second embodiment of a light-emitting electronic device according to the invention, configured as a voltage indicator or regulator; and
FIG. 7 is an equivalent circuit of the light emitting device of FIG. 6.
DESCRIPTION OF EMBODIMENTS
Referring first to FIG. 1, a single crystal diamond 10 is fixed to a reflective aluminium base 12. The diamond may be a synthetic or natural type I or type II diamond, but not a type IIB diamond. The upper surface of the diamond crystal 10 is implanted with boron ions to define a shallow p-type region 14 in the diamond substrate. The p-type region has a depth of between 0.5 μm and 1 μm. An ion dose of 20 KeV is applied, which provides an ion density of 10 18 to 10 21 boron ions cm -2 . On top of the p-type region 14 a layer of diamond is deposited by a chemical vapour deposition (CVD) process to define three discrete regions 16, 18 and 20, which are grown as single crystal on the p-type implanted regions of the intrinsic diamond substrate.
The region 16 comprises a lightly p-doped CVD layer while the region 18 comprises intrinsic diamond. For example, the region 16 can be formed by using diborane gas (B 2 H 6 ) as a dopant in the CVD process, to obtain a concentration of less than 1000 ppm of boron. The resulting doped region 16 has a low vacancy content. The region 20 is formed by a high growth rate plasma jet CVD process (also known as flame or combustion CVD), resulting in a layer with large numbers of vacancies.
The discrete regions 16, 18 and 20 of the deposited layer are separated and insulated from one another by a transparent insulating layer 22 which may comprise, for example, HFO 2 , Al 2 O 3 , SiO 2 or SrTiO 3 (perovskite). The insulating layer can be applied by CVD or PVD techniques. Finally, electrically conductive contacts 24, 26 and 28 comprising separate layers of indium tin oxide are deposited above the respective regions 16, 18 and 20, for example, by sputtering, evaporation or electron beam deposition. A conductive electrical contact 29 is applied to one end of the p-type implanted region 14. The resulting device effectively comprises three separate diodic structures, each of which emits light when sufficiently forward-biased electrically. From left to right in FIG. 1, the three structures emit green, blue and red light respectively.
The method of the invention takes advantage of the transparency of diamond, whether a diamond crystal or a layer deposited by a CVD process, to provide a light emitting device. The use of transparent indium tin oxide contacts and transparent insulating layers ensures that the light emission qualities of the device are not impaired. The aluminium layer 12 in FIG. 1 serves as a reflector, to maximize light emission of the illustrated device.
Devices of the kind described above have numerous possible applications. For example, a multiple-pixel RGB display could be manufactured using a multiplicity of three-colour devices as described. Another application is a multi-colour visible voltage regulator or indicator device, which includes a plurality of switching devices such as diodes, each with a different switching threshold voltage, to provide an integrated device which emits different colour light according to the voltage level applied to it. Another possible application of the invention is in an optical logic device, an example of which is illustrated schematically in FIG. 2.
In FIG. 2, a type Ia single crystal diamond substrate 30 is divided into three regions, which correspond to an OR gate, an AND gate, and a NOT gate. Instead of being electrical gates, the gates are optical, in the sense that they respond to an optical input and provide an optical output. The surface of the diamond substrate is implanted with p-type ions to define a first p + region 32, a second p + region 34, and third and fourth p + regions 38 separated by a p-doped region 40. The p + region 32 serves as part of both the OR and the AND gates.
Dealing first with the OR gate, a layer of intrinsic diamond comprising first and second regions 42 and 44, separated by an insulating region 46 of SiO 2 , is deposited by a CVD process as described above. A titanium layer 48 is deposited, for example, by sputtering, above the regions 42, 44 and 46. A further layer 50 of intrinsic diamond is deposited by a CVD process on the titanium layer directly above the region 42 and a transparent conductive contact 52 of indium tin oxide is deposited on top of the layer 50. The contact 52 can be deposited by the same techniques used to produce the contacts 24, 26 and 28.
The AND gate is formed by depositing regions 54 and 56 of intrinsic diamond above the p + regions 32 and 34. A region 58 of SiO 2 separates the p + layers 32 and 34 at the surface of the substrate 30. A titanium layer 60 is deposited above the regions 54 and 58 and makes contact with the surface of the p + region 34. A titanium layer 62 is also deposited above the region 56. A further diamond layer 64 is deposited on the titanium layer 62, and an indium tin oxide contact 66 is deposited on the layer 64. The titanium layers 48 and 62 precede the respective diamond deposition layers 50 and 64 in order to withstand the high temperatures involved in the CVD deposition process.
Finally, the NOT gate is formed by depositing diamond regions 68 and 70 above the p + regions 36 and 38. The diamond regions are separated by an SiO 2 insulating region 72, which is deposited above the p-type region 40. An aluminum layer 74 is deposited above the region 68 and 72, while an indium tin oxide contact 76 is deposited on the diamond region 70.
The three indium tin oxide contacts 52, 66 and 76 are connected together to the positive terminal of a voltage source V, while the negative terminal of the voltage source is connected via an indium tin oxide contact 78 to the p + region 32.
The OR gate has two active input regions marked A and B which correspond to the photodiodes A and B in the schematic diagram of FIG. 3. If either the A or B photodiodes are illuminated, the device emits light, thus effectively providing an OR function. Similarly, if both the photodiode input structures A and B of the AND gate are illuminated, the device emits light. Finally, if the photodiode sensor A of the NOT gate is illuminated, no light will be emitted, while an absence of illumination will cause a light output.
In the described example, using intrinsic diamond layers deposited by a CVD process, blue light is emitted by the respective devices. Obviously, a different colour light output could be obtained by using a different CVD process.
Referring now to FIGS. 6 and 7, a visible voltage indicator or regulator and its respective equivalent circuit is shown in which a variable voltage source 82 is connected in series with three zener diodes Z1, Z2 and Z3, having respective breakdown voltages V1, V2 and V3. The First zener diode Z1 is connected between the negative terminal of the voltage source 82 and the indium tin oxide contact 52, the second zener diode Z2 is connected between the contacts 52 and 66, and the third zener diode is connected between the contacts 66 and 76. The voltage regulator 80 has a patterned aluminum base 84 with windows 86,88 and 90 formed therein. Both the electrical contact 29 and the aluminium base 84 are earthed to prevent a build up of charge in the diamond crystal layer 10.
When a voltage level V1 is applied across the terminals, the region 16 emits green light through the window 86. When the voltage is stepped up to V2, the region 18 emits blue light through the window 88, and when the voltage is raised to V3, the region 20 emits red light through the window 90.
This embodiment can be used as a visible voltage indicator or regulator. Green light is emitted if the voltage V1 is applied, both green and blue light is emitted if the voltage V2 is applied, and green, blue and red light is emitted if the voltage V3 is applied.
Colour sensitive detectors, such as photodiodes, phototransistors or photomulitiplier tubes with various filter combinations could be used to provide a voltage signal output from the various coloured light outputs. | A light emitting electronic device has a substrate of transparent intrinsic diamond material with a p-type region formed in it by implantation of boron ions. Discrete transparent layers of diamond material are deposited over the p-type region, each with different electric characteristics. Transparent conductive contacts are formed above the transparent layers, which are separated by a transparent insulation layer, and a conductive contact is applied to the p-type region of the substrate. The different regions of the device emit different colours of light. Various different embodiments and methods of making the device are described. | 7 |
BRIEF DESCRIPTION OF THE PRIOR ART
The present invention relates generally to a composite container having a peelable membrane type patch top member heat sealed to one end of the container by a synthetic plastic coextruded film laminate including at least two layers, the degree of adhesion between the laminate layers being less than that between the laminate layers and the adjacent surfaces of the associated members, respectively, and to the method for forming said container.
Containers having a peelable heat sealed closure member are known in the art as evidenced by the patents to Johnson et al U.S. Pat. Nos. 3,892,351 and 3,973,719, Turpin et al U.S. Pat. No. 3,940,496 and Sturm U.S. Pat. No. 3,946,871. The use of a heat sealable coextruded film laminate for closing a package is also known, as evidenced by the patent to Stanley et al U.S. Pat. No. 3,655,503. Owing to the selection and arrangement of the laminate layers, opening of the package and delamination of the heat sealed laminate layers occurs in an unpredictable manner. The present invention was developed to avoid the above and other drawbacks of the known containers including heat sealed closure members.
SUMMARY OF THE INVENTION
Accordingly, the present invention relates to a composite container including a peelable patch top closure assembly having predictable opening characteristics. The composite container includes a generally tubular composite body member having a reversely outwardly curled body end, a generally disk-shaped membrane-type patch top closure member extending across said reversely curled body end, and a heat sealable coextruded film laminate bonding said patch top member in sealed closed relation with said reversely curled body end. The coextruded film laminate includes at least two laminate layers which are bonded to each other by a bond having a coefficient of adhesion which is less than the coefficients of adhesion between said laminate layers and said patch top member and said reversely curled body end, respectively, whereby upon removal of the patch top member from the container end, the laminate layers tear apart at their interface surface in a predictable manner to effect opening of said body member end.
Accordingly, a primary object of this invention is to provide a peelable patch top closure assembly for a composite container end, wherein a heat sealable coextruded film laminate bonds said patch top member in sealed relation to said container end.
Another object of the invention is to provide an improved method of manufacturing a composite container including a peelable patch top closure member which has predictable opening characteristics.
BRIEF DESCRIPTION OF THE DRAWING
Other objects and advantages of the invention will become apparent from a study of the following specification when viewed in light of the accompanying drawing, in which:
FIG. 1 is an exploded perspective view of the container assembly of the present invention;
FIG. 2 is a detailed cross-sectional view of a first embodiment of the present invention;
FIGS. 3 and 4 are detailed cross-sectional views respectively, of the first embodiment illustrating the patch top being progressively peeled away;
FIG. 5 is a detailed cross-sectional view of a second embodiment of the present invention;
FIGS. 6 and 7 are detailed cross-sectional views respectively, of the second embodiment illustrating the patch top being progressively peeled away; and
FIG. 8 is a detailed cross-sectional view illustrating the results produced by the final pressing assembly step.
DETAILED DESCRIPTION OF THE INVENTION
Referring first to FIG. 1 the composite container of the present invention includes a generally tubular helically wound composite body member 10 including a helical butt joint 11, a reversely outwardly curled upper end 12, a disk-shaped membrane patch top member 30 for closing the reversely curled end of said container and including a pull tab 32, and a synthetic plastic overcap 50 mounted on the container in protective relation with the patch top member 30.
As shown in FIG. 2, the body member 10 includes an outer label layer 14 (formed of paper or metal foil), a fibrous body layer 16, an inner liner layer 18 (preferably formed of aluminum foil), and a cast or blown coextruded film laminate 20 including first and second synthetic plastic layers 20a and 20b, respectively. The first layer 20a is preferably thicker than the second layer 20b and is made from a polymer noted for its toughness and abrasion resistance, such as polypropylene (PP). Moreover, the first layer 20a has a higher softening temperature than layer 20b. The second layer 20b is preferably formed of a resin blend which makes fusion seals to a variety of resin types under a range of time, temperature, and pressure conditions. It has been found that a resin blend (physical mixture) of polyethylene (PE) and ethyl methyl acrylate (i.e., Gulf's Poly Eth #2255) (EMA) is particularly suited for this purpose. With little or no EMA in the blend, intraply adhesion between layers 20a and 20b will invariably be weak (typically 1/2 lb. peel strength per square inch). With 50% or more EMA in the blend, intraply adhesion increases and approaches the film tearing strength. By selecting the proper EMA:PE ratio in the blend, the ply adhesion for the intended end use can be achieved. In accordance with the present invention, the blend is about 70% EMA to about 30% polyethylene, thereby to achieve an adhesion strength of at least 3 pounds per square inch.
The membrane type patch top member 30 includes a flexible layer 34 (formed from a material such as metal foil, heat resistant synthetic plastic or paper), and a surface coating layer 36 selected from a variety of resins, such as PE, surlyn (DuPont ionomer), EMA, ethylene vinyl acetate, or blends thereof.
The can body 10 is formed by helically winding the inner liner and fibrous body wall layers on a mandrel. Coextruded film laminate layer 20 is first wound on the mandrel followed by liner layer 18, fibrous body wall layer 16, and label layer 14, respectively. The helically wound body member is then cut to the proper length, whereupon one end is reversely outwardly curled to cause the coextruded film laminate layer 20 to extend around the uppermost extremity of the reversely curled body end 12. The patch top member 30 is then placed on the reversely curled end and heat sealed thereto, whereupon the protective synthetic plastic overcap 50 is mounted over the patch top member 30 in protective relation thereto.
OPERATION
Upon removal of the protective overcap member 50, opening of the container one end is effected by pulling the patch top tab 32, whereby, owing to the strong intraply adhesion between layers 20b and 36, and the weaker intraply adhesion between layers 20a and 20b, pulling of the tab 32 causes coextruded film laminate layer 20b to initially tear through itself and to be progressively peeled from layer 20a at the outer periphery of the fusion seal 60, as shown in FIG. 3. Upon further pulling of tab 32, layer 30b tears through itself again, whereby a section 22 of the layer 20b separates from layer 20b and remains fusion bonded to layer 36 of the patch top member, as shown in FIG. 4. The tab is then progressively pulled to effect complete removal of the patch top 30 from the body member 10, causing a circular section 22 of layer 20b to remain attached to the patch top 30.
In the second embodiment of FIG. 5, the coextruded film laminate 20' is bonded to the inner surface of the patch top member 30', whereby less of the specialized coextruded film laminate material is required. The film laminate 20' includes a layer 20a' of polypropylene, and a layer 20b' formed from a blend of PE and EMA as discussed above. The body member 10' is coated with a layer 36' formed from resins which adhere to the EMA:PE blend, such as a coextruded film of PP-EMA-PE, high density PE-PE, PP (Homopolymer)-PP (Copolymer) or a single layer of PP (Copolymer). The patch top member 30' is heat sealed to the reversely curled body one end 12' to form a circumferential fusion seal 60'. In this embodiment a circular score line 38' or other line of weakness may be provided in the coextruded film laminate 20 to allow layer 20b' to more easily tear through itself, thereby to prevent an undesirable thin film of layer 20b from remaining across the container one end upon removal of the patch top member 30' .
Removal of the patch top member 30' is effected by pulling tab 32', thereby causing layer 20b to tear through itself and separate from layer 20a at the outer periphery of the fusion bond 60', as shown in FIG. 6. Upon further pulling of the tab 32', the layer 20b' tears through itself again at the score line 38', whereby a section 22' of layer 20b' is separated from layer 20b' and remains bonded to the reversely curled body one end 12'. The tab 32' is then progressively pulled to effect complete removal of the patch top 30' from the body member 10', thereby causing a circular section 22' to remain attached to the reversely curled end 12'.
As shown in FIG. 8, as a final step, the patch top closure member 130 may be pressed downwardly, with the application of heat, upon the body member 110, thereby to effect a thinning or reduction in thickness of the layer 120b from thickness t 1 to the reduced thickness t 2 '. Consequently, during opening of the container, the patch top closure member 130 may be peeled from the composite container body 110 in a positive manner.
While in accordance with the provisions of the Patent Statutes, the preferred forms and embodiments have been illustrated and described, it will be apparent that changes and modifications may be made without deviating from the inventive concepts set forth above. | A composite container including a peelable patch top closure assembly, and a method for forming the same, are disclosed, including a tubular composite body member reversely outwardly curled at one end, a generally disk-shaped membrane patch top member extending across the reversely curled body end to close the same, and a heat sealable coextrudable synthetic plastic film laminate bonding the patch top member to the reversely curled body end, the coefficient of adhesion between the laminate layers being less than that between the laminate layers and the adjacent surfaces of the associated members, respectively. | 1 |
BACKGROUND
1. Field of Invention
The present invention relates to improved fastening means for a pair of flaps or the like, and more particularly to improved magnetic fastening means for use in place of buttons, snaps, and the like.
2. Brief Summary of the Prior Art
Conventional fastening means such as buttons, snaps, and the like, are presently and will probably remain for the forseeable future, the most widely used devices for releasably joining a pair of fabric flaps or the like. The reasons for this are simple. Conventional fastening devices are generally uncomplicated devices which are easy to use, and inexpensive to manufacture and install. Despite these facts, however, there remain certain situations in which, and certain individuals to whom, the use of such conventional fastening means are not particularly well adapted. Thus, for example, in the fashion context the visible presence of a button or snap may be considered to be aesthetically unsatisfactory, yet the closure required may not be adapted for the use of a zipper or other conventionaL device. Similarly, conventional buttons and snaps in other contexts may be inappropriate where exposure to the elements may cause rusting, leakage, or other forms of damage. Various attempts to alleviate these problems are present in the art, including the use of comparatively expensive weatherproofing materials and the use of protective flaps which render the operation of the fastener somewhat awkward. Also, for some people, most notably the elderly, the very young, and those who for one reason or another lack normal manual dexterity, the operation of conventional fastening means, including zippers and even Velcro fasteners as well as conventional buttons and snaps, is extremely difficult.
In response to the above deficiencies, fastening means relying upon magnets to releasably hold a pair of flaps or the like together have been developed in an attempt to facilitate the fastening and unfastening operations. Heretofore, such devices have relied upon direct flush abutting contact between magnetic surfaces of opposite polarities, or between a magnetic surface and a ferromagnetic surface, to establish the desired releasable locking engagement.
As used herein the terms "magnetic" and "ferromagnetic" are used to distinguish between permanently magnetized surfaces and surfaces which may be temporarily magnetized when in contact with or in close proximity to a permanent magnet, respectively. U.S. Pat. No. 3141216 to Brett, issued July 21, 1964, is exemplary of such devices. It will be understood, however, that such prior devices have been found to be economically impractical due to their weight in comparison to conventional devices, their thickness in comparison to the flaps they are intended to join and the inherent difficulty of mounting the operative fastening elements so as to allow direct flush abutting contact therebetween. Brett shows the later of these problems clearly. Thus, if the operative elements are to be located in holes in the flaps there must be some sort of mechanical link between the flap and the fastener to maintain the fastening elements in position. In such a case the periphery of the holes in the flaps is the weakest portion of the link and is vulnerable to tearing with a resultant dislodging of the fastener. Alternatively, if the fastener is mounted without making a hole in the flap, for example by crimping a portion of the flap between the operative elements and a cap, the operation of the device itself will require the exertion of forces which tend to pull the fastener apart thereby dislodging it from the flap.
II. SUMMARY OF THE PRESENT INVENTION
The present invention provides an improved means for releasably fastening a pair of flaps or the like together by means of magnetic attractive forces. More particularly the present invention contemplates a magnetic fastening means wherein fastening is accomplished between two ferromagnetic elements in a magnetic field rather than by direct engagement between a pair of magnets. Specifically, a fastening means is provided having first and second ferromagnetic plates, an elongated ferromagnetic element of cross sectional area smaller than the area of the surface of either plate affixed to one end thereof substantially normal to a surface of the first of the plates, and magnetic means affixed in close proximity to (permissably including direct contact with) the elongated element along a substantial portion, but not all, of its length. The present invention further contemplates that the above operative elements will be mounted upon a pair of thermoplastic strips, which strips are affixable to facing surfaces of the flaps, by means of first and second thermoplastic mounting elements which are adapted to receive and hold the respective plates. The mounting elements are contemplated to be affixed to the respective strips in such a way that the nonsecured end of the elongated element releasably lockably engages a surface of the second plate in flush abutting relation when the device is closed.
It is thus an object of the present invention to provide an improved magnetic fastening means for two members which is lightweight, economical to manufacture and install and yet easily manipulable into and out of a secure fastening position.
It is also an object of the present invention to provide an improved magnetic fastener of the type described which is not visible when the members are joined thereby maintaining the aesthetic beauty of the joined members and protecting the fastener from the external environment.
It is further an object of the present invention to provide an improved magnetic fastener of the type described which requires only approximate alignment of the mounting means as the respective members are brought together to effecutate engagement.
Still further it is an object of the present invention to provide an improved fastening means of the type described which is securely mountable to the members to be joined without rendering the members vulnerable to damage or the fastening means vulnerable to dislodgement.
BRIEF DESCRIPTION OF THE DRAWINGS
These, as well as other features, objects, and advantages of the present invention will be more clearly understood by reference to the following detailed description of exemplary embodiments of the present invention and to the drawings in which:
FIG. 1 is an exploded perspective view of a fastening device in accordance with the present invention;
FIG. 2 is a vertical section of the fastening means of FIG. 1 wherein the two fastening members are shown in open or separated relation;
FIG. 3 is a view similar to FIG. 2, but showing the fastening members in closed relation;
FIG. 4 is an exploded perspective view of a second embodiment of a fastening device in accordance with the present invention;
FIG. 5 is a vertical section of the fastening means of FIG. 4, wherein the two fastening members are shown in closed relation;
FIG. 6 is a top view of a jig suitable for use in the assembly of a fastening device in accordance with the present invention; and
FIG. 7 is a side section of a portion of the jig of FIG. 6 taken along the line 7--7.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now specifically to the drawings it will be noted that a first (FIG. 1-3) and a second (FIG. 4-5) embodiment of a magnetic fastening means in accordance with the present invention is shown, while FIGS. 7 and 8 show a jig suitable for use in the assembly of the respective fastening members of the present invention as hereinafter more fully appears.
With reference to the first embodiment, it will be seen from the drawings that a pair of correspondingly apertured thermoplastic strips 2 and 4 are provided. These strips are adapted to be affixed, by sewing or other convenient means, to facing surfaces of the flaps (not shown) such that the apertures 5 and 9 of the respective strips will be in alignment when the flaps are in the desired relative special orientation for fastening.
Fastening member 6 includes a first thermoplastic support cup 10 having peripheral wall portion 12 and an end wall portion 14 collectively defining a mounting cavity 16, and flange portion 18 extending outwardly of the peripheral wall 12 adjacent the open end of the cavity 16. The flange 18 is affixed to the side of strip 2 which is to be adjacent a flap, on center about the aperture 5 therein. A first ferromagnetic plate 20 having an upper surface 22 and a lower surface 24 is affixed by frictional engagement with projections 25 and 27, or by other convenient means such as gluing, within the mounting cavity 16 such that its lower surface 24 is substantially flush against end wall portion 14. A ferromagnetic post 26 having an inner end 28, an outer end 29, a cross sectional area smaller than the area of surface 22 and smaller than the area defined by apertures 5 and 9, and a length greater than twice the distance between surface 22 and the open end of cavity 16, is affixed substantially centrally of and normal to surface 22 at end 28 thereof so as to extend upwardly through aperture 5. Optionally, plate 20 and post 26 may be formed as an integral unit. Disposed between surface 22 and strip 2 within cavity 16 is a first annular magnet 30 such that a surface 31 thereof of one polarity lies adjacent upper surface 22 of plate 20 and such that post 26 extends through central opening 32 thereof.
Fastening member 8, on the other hand, comprises a second thermoplastic support cup 34, substantially identical to support cup 10, having a peripheral wall portion 36 and an end wall portion 38 collectively defining a second mounting cavity 40, and flange portion 42 extending outwardly of the peripheral wall 36 adjacent the open end of the cavity 40. The flange 42 is affixed to the side of strip 4 which is to be adjacent a flap, on center about aperture 9 therein. A second ferromagnetic plate 43, substantially identical to plate 20, having an upper surface 44 and a lower surface 46 is affixed by frictional engagement with projections 48 and 50, or by other convenient means such as gluing, within said mounting cavity 40 such that its lower surface 46 is substantially flush against end wall 38. Disposed between surface 44 and strip 4 within cavity 40 is a second annular magnet 52 such that a surface 54 thereof, of opposite polarity to the polarity of surface 31 of magnet 30, lies adjacent to surface 44 of plate 43 and such that the central opening 56 therein is aligned on center with aperture 9. It should also be understood that the edges of apertures 5 and 9 are preferrably fused to prevent tearing of strips 2 and 4, and that the area between the apertures and the flange attachment may be reinforced if desired. I have in fact found that initially fusing the entire area of the strips about which the support cups are to be attached greatly facilitates the formation of the apertures by a simple punch out method and also acts to reinforce the strip.
Assembly of this device is preferably accomplished using an ultrasonic tool to weld te strips to the flanges of the respective support cups. Ultrasonics is preferred because it is easier to control than conventional heat welding yet results in a similar weld. I have also found that a jig 58, substantially as shown in FIGS. 6 and 7, facilitates assembly of the present fastening means. This jig is preferably a unitary, milled, substantially rectangular metallic member adapted to fit under the welding head of a conventional ultrasonic welder. Milled in the top surface 62 of the jig 58 is a slot 60 such that rails 64 and surface 66 allow one of the thermoplastic strips to lie substantially flat against surface 66 and be held substantially stationary between rails 64.
Means such as hole 68 designed to fit a mounting pin on the welding machine are provided for holding the jig stationary relative to the welding machine (not shown). Also, as the cross-sections apertures 5 and 9 are larger than the cross section of post 26 to facilitate engagement of the fastener along the sloped edges 57 of magnet 52, it is convenient to construct jig 58 such that the pin projecting through hole 68 from the welding machine projects through the aperture in the strip adjoining the aperture about which the support cup flanges are being welded in such a way that the alignment of the aperture and the central opening of the magnet is maintained during the welding operation. Cavity 70 is drilled or milled such that the respective support cups will fit therein with the flanges substantially flush with surface 66. In the preferred case, the flanges will be flush with surface 66 and be provided with projections (not shown) extending above surface 66. In this case the assembler simply places an assembled fastening member into cavity 70, places the thermoplastic strip over the fastening member in slot 60, such that the aperture is aligned with the central opening in the magnet and the adjoining aperture is hooked over the pin projecting through hole 68, and then activates the ultrasonic welder which melts and squashes the projections as well as partially melting the strip in the area of contact with the flange thereby forming a strong weld between the flange and strip.
It will be understood that any desired number of fastening members may be attached to a single strip in this manner, and that large economies of scale may be realized in attaching a plurality of fastening members to the same strip at the same time. The completed strips are then appropriately affixed to the respective flap surfaces to be joined such that fastening members of one type are always maintained opposite fastening members of the other type.
The design of this fastening means is such that the magnets need not come in direct contact with each other. Instead the magnetic fields present in the female member actually draw the end 29 of the post 26 of the male member into engagement with surface 44 of plate 42 as the fastening members are brought together thereby avoiding the squeezing needed to engage snaps and the push-pull forces needed to engage buttons. If perchance the post fails to engage aperture 9 and the central opening in magnet 52 thereunder, the necessary alignment, which need only be approximate to result in appropriate engagement, is a simple matter even for a handicapped individual. Relatively strong magnets are used to assure the security of the engagement. However, as the area of contact between the post 26 and the plate 42 is small, the axial movement of the fastening members away from each other necessary for disengagement of the device is a relatively simple manipulation.
The second embodiment shown is similar in operating principle and assembly to the first yet may prove superior thereto at such time as powerful yet small rare earth magnets such as samarium cobalt become readily and economically available. In this embodiment the fastening members 102 and 104 are ultrasonically welded to thermoplastic strips 106 and 108, however, in this case fastening member 102 includes a support cup 110 having peripheral walls 112 and an end wall 114 forming a mounting cavity 116, and a flange 118 extending outwardly from the open end of cavity 116, said flange being welded to the periphery of an aperture 120 in strip 106. A ferromagnetic plate 122 having an upper surface 124 and a lower surface 126 is affixed within cavity 116 by frictional engagement with projections 128 and 130, gluing, or other convenient means, with its lower surface 126 against end wall 114.
Fastening member 104, on the other hand, includes a support cup 132 having peripheral walls 134 substantially shorter than walls 112 and an end wall 136 collectively forming a mounting cavity 138, and a flange 140 extending outwardly of wall 134 adjacent the closed end of cavity 138. The open end of cup 132 is further adapted to fit within cavity 116 in telescoping relation. A ferromagnetic cup 142 having peripheral walls 143 and an end wall 144 is affixed within cavity 138 such that end wall 144 lies adjacent to end wall 136 and peripheral walls 143 extend beyond the outer ends 146 of walls 134. Additionally, the outer ends 148 of walls 143 are designed to bear against surface 124 when the fastener is closed. A magnet 150 is affixed within the cavity 152 formed by walls 143 and 144, adjacent wall 144; the magnet extending upwardly from wall 144 less than the height of wall 142.
It will further be seen that fastening members 102 and 104 may be mounted substantially as above described to thermoplastic strips 106 and 108 either to the upper surfaces 164 and 166 of flanges 118 and 140, to the lower surfaces 168 and 170 thereof, or to a combination thereof according to whether or not the particular application lends itself to the presence of apertures in either, both, or neither of the strips.
This second embodiment has several distinct advantages, provided small, lightweight magnets of sufficient strength are available to assure secure fastening at economical cost. In addition to being lightweight and providing a very secure lock in the closed position due to the increased area of contact between the temporarily magnetized ferromagnetic cup 142 and plate 122, the fastener when closed is thinner due to the telescoping engagement feature and is thus more aesthetically pleasing in its approximation of conventional fasteners. The fastener unit is also more rigid, stronger, and less likely to disengage unintentionally due to extraneous forces due to the telescoping engagement of the fastening member. The device itself is additionally easier to use because it approximates a snap and is thus familiar and provides a comparatively large area for engaging the male with the female member.
It should be understood that the embodiments and practices described and portrayed herein have been presented by way of disclosure, rather than limitation, and that various modifications, substitutions, and combinations may be effected without departure from the spirit and scope of this invention in its broader aspects. | Fastening means for a pair of flaps or the like are provided having first and second ferromagnetic plates, an elongated ferromagnetic element of cross-sectional area smaller than the area of the surfaces of either plate affixed at one end thereof substantially normal to a surface of the first of the plates, and magnetic means affixed in close proximity to the elongated element along a substantial portion, but not all, of its length. It is also contemplated that the above elements will be mounted by means of first and second thermoplastic mounting elements upon a pair of thermoplastic strips, which strips are affixable to facing surfaces of the flaps, in such a way that the nonsecured end of the elongated element releasably lockably engages a surface of the second plate in flush abutting relation when the fastening means is in the closed position. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to grinding machines with expansible grinding tools and in particular to devices for controlling the expansion of the grinding tool.
2. Description of the Prior Art
Expansible grinding tools are used, for example, in the machining of internal bores and grinding machines using such tools comprise means for rotating the tool and a device for controlling the expansion of the tool. The tools themselves comprise in the majority of cases abrasive stones, or diamonds, disposed around the periphery of a support cylinder and able to move radially under the action of axial movement of a cone in the support cylinder. Such movement of the cone can, for example, be effected by a rod integral with the cone and fast for translational movement with a screw engaged with a fixed nut and rotatable via a reduction gear train by a driving motor. In known grinding machines the whole of the expansion control mechanism is carried directly by the frame of the machine. The mounting of the driving motor of the expansion screw on the machine frame makes it necessary to provide a sliding connection between the shaft of the motor and the screw. Moreover, when a breakdown occurs in the expansion control mechanism, the grinding machine becomes unusable until the expansion control mechanism has been repaired.
OBJECT OF THE INVENTION
It is an object of the present invention to provide an improved grinding tool expansion control device which obviates such drawbacks.
SUMMARY OF THE INVENTION
According to one aspect of the invention there is provided a device for controlling the expansion of an expansible grinding tool whose expansion is effected by axial movement of a cone rigid for translational movement with an axially movable expansion rod. The device comprises a rotatable screw fixed for translational movement to the rod, a fixed nut engaged by the screw, and a driving motor arranged to effect controlled rotation of the screw to cause axial movement of the said rod and cone, the device being disposed in a monobloc grinding head unit which can be removably inserted between a grinding machine and the said expansible grinding tool.
In the event of a breakdown of the expansion mechanism, the grinding head is withdrawn and it is replaced by another grinding head in working condition. The down-time of the machine is thus very short, which is very important particularly in the case where the grinding machine is used in a production line for making bores in mass-produced parts.
The driving motor is, preferably, a stepping electric motor with programmed digital control.
The frequency of the pulses supplied to the motor determines the rate of movement of the expansion rod, and thus the expansion and contraction speeds of the grinding tool. It is consequently possible to adjust these speeds accurately by altering this frequency. Moreover, the stroke of the expansion rod depends upon the number of pulses supplied to the motor; the adjustment of this number determines said stroke accurately.
Expansion control devices embodying the invention can be used both with a stone grinding tool and with a diamond grinder. In the first case, the expansion control device can advantageously be provided with a proximity detector arranged to be actuated during the return stroke of the expansion rod by a control element moving with the rod in order to initiate the supply of motor control pulses for the forward stroke. In the second case, the control device can comprise means for transmitting to the motor an auxiliary pulse train after machining a given number of parts, the starting point of the forward stroke of the expansion rod being thereby shifted so as to take up the low wear of the grinding tool.
According to another aspect of the invention, there is provided a grinding head for interposition between a grinding machine and an expansible grinding tool provided with an expansion cone, the head comprising means arranged to transmit rotary motion from the grinding machine to the tool, and control means arranged to control expansion of the grinding tool by controlled linear movement of the expansion cone, said control means including two co-operating threaded elements one of which is fixed and the other of which is couplable for joint linear movement with the cone, and drive means arranged to effect controlled rotation of the movable threaded element, the head being removable as a whole from grinding machine.
BRIEF DESCRIPTION OF THE DRAWING
A grinding head incorporating an expansion control device in accordance with the invention will now be particularly described, by way of example, with reference to the accompanying diagrammatic drawing in which:
FIG. 1 is an axial cross-section of the head;
FIG. 2 is a schematic diagram of the expansion control device incorporated in the grinding head;
FIG. 3 is a diagram of a grinding cycle in the case of a stone grinder; and
FIG. 4 is a diagram of a grinding cycle in the case of a diamond grinder.
DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in FIG. 1, the grinding head comprises a body 1 which can be fixed to a grinding machine by screws passing through holes 2 of the collar 1a of the body 1. A pin 8 rotatably mounted in the body 1 by means of roller bearings 9 serves to transmit rotary motion from the grinding machine to an expansible grinding tool secured to the pin 8 by engagement in a female cone 8a provided in the lower end portion of the pin 8, the tool being held there by a lock-nut engaging an external thread of the cone 8a.
A nut 3 is fixed by means of screws 4 to the bottom portion of the body 1. A screw 5 is engaged in this nut 3 and extends into an internal space of the body 1. A sleeve 6 is rotatably mounted within an axial throughgoing hole of the screw 5 by means of a needle rollers (bearings) 7. The sleeve 6 surrounds the pin 8 and is slidable relative thereto.
An auxiliary pin 10 is slidably mounted in the pin 8. An expansion rod 11 is screwed into the lower end of the pin 10 and connects with an expansion cone 11a (FIG. 2) of the expansible grinding tool. A bushing 12 extends transversely through the pin 10 and engages in longitudinal ports 8b of the pin 8. The auxiliary pin 10 is thereby rotated by the pin 8 but can slide axially relatively to it.
A shaft 13 extends axially through the bushing 12 and the ends of this shaft engages in the sleeve 6. The sleeve 6 has a shoulder 6a disposed between two needle-bearing abutments 14a and 14b; these abutments are housed in a widened portion 5a of the screw 5 and are retained there by a toothed wheel 15 fixed to the bottom portion of the screw 5. It will thus be seen that the sleeve 6 rotates with the pin 8, but can move axially thereof in unison with axial movement of the screw 5, to move the expansion rod 11 axially.
Axial movement of the screw 5 is effected by rotating the screw 5 relative to the fixed nut 3. To this end, the toothed wheel 15 meshes with a very long pinion 16 which itself meshes with a pinion 17 integral with a toothed wheel 18. The toothed wheel 18 meshes with a pinion 19 keyed on the output shaft 20 of a digitally-controlled stepping electric motor 21. When the output shaft 20 is turned by one step, the screw 5 turns through a certain angle due to the nut 3 being fixed; the screw 5 will also move axially and cause a corresponding axial movement of the expansion rod 11.
The widened portion 5a of the screw 5 has around its periphery a groove 5b in which is engaged an index 22 arranged to move in front of a scale 23. The index 22 is fast with a rod 24 slidably mounted in the body 1 and carrying adjacent its upper end two adjustable control elements 25a and 25b arranged to co-operate with two proximity detectors 26a and 26b.
Digital control of the motor 21 is effected in the usual manner with the control means comprising a pulse generator, means for adjusting the frequency of the pulses to a first value corresponding to a fast feed speed of the expansion rod 11, and to a second value corresponding to a slow feed speed of said rod, and means for adjusting when desired the number of pulses supplied to the motor, both during fast feed and slow feed.
The operation of the described grinding head differs slightly according as to whether the grinding tool is of the stone or diamond type but in general involves the fast forward feed of the expansion rod and cone followed by slow forward feed until machining is completed. The exapnsion rod and cone are then retracted in a return stroke.
When the grinding tool has abrasive stones 28 carried by a support 27, the rate of fast foward feed is set beforehand as is the number of pulses supplied during this fast feed; the rate of the slow forward feed is also preset. The end of slow feed is determined by the generation of an electric signal indicating that grinding has been completed. This signal is produced, for example, by means of an air leak between a nozzle fixed on the grinding tool and the wall of a bore being machined, the variations in air pressure being detected by a mechanical contact arrangement. Alternatively, the signal can be produced by means of a conical ring arranged to enter into a bore being machined to an extent dependent on the bore diameter, a micro-contact being actuated upon the ring entering a predetermined distance into the bore.
On completion of a grinding operation, the expansion rod 11 is retracted until the slide 25a actuates the proximity detector 26a. As a consequence of the wear of the stones, the rod 11 does not return as far as its initial starting point as is shown by FIG. 3 which represents the stroke of the expansion rod 11 in time terms, references 29, 30, 31 respectively indicating the fast feed stroke of the rod, its slow feed stroke and its return stroke.
The actuation of the proximity detector 26b takes place when the stones are fully worn, at the end of a feed stroke 30a. The following return stroke 31a then returns the expansion rod 11 to its starting position to permit a change of stones.
When the grinding tool is of the diamond type, then due to the very low wear of the tool the number of pulses supplied during slow feed can also be preset since the axial position of the cone is itself a sufficient regulator of the grinding operation; as a result, there is no need to provide additional means for indicating that a desired workpiece dimension has been reached. As there is practically no wear on the diamond, the expansion rod returns after each machining oeration to its starting point, as can be seen in FIG. 4, in which references 32, 33 and 34 respectively indicate the fast feed stroke of the rod, its slow feed stroke, and its return stoke.
In order to compensate for any slight wear of the tool that may occur, after the machining of a certain number of parts, the starting point of the run of the expansion rod 11 is staggered by sending to the motor a train of additional pulses. The stroke of the expansion rod after the sending of this train of pulses is shown in FIG. 4 at 32a, 33a and 34a.
If the expansion control device breaks down, the grinding head can be removed from the grinding machine by unscrewing the fixing bolts passing through the holes 2, and replaced by a head in working condition, this operation requiring very little time. The defective head is then repaired independently in the workshop. | A device for controlling the expansion of an expansible grinding tool includes control means for effecting controlled axial movement of a cone in the tool. The control means includes a screw engaging a fixed nut and controllably rotatable by a driving motor, the resultant axial movement of the screw being transmitted to the cone. The expansion control device is provided in the form of a removable grinding head unit arranged to be inserted between a grinding machine and the grinding tool. The grinding head unit also includes means for transmitting rotary motion from the grinding machine to the grinding tool. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the U.S. national phase application of PCT International Application No. PCT/EP2009/051873, filed Feb. 17, 2009, which claims priority to German Patent Application No. 102008 009 834.5, filed Feb. 18, 2008, German Patent Application No. 10 2008 021 524.4, filed Apr. 30, 2008, and German Patent Application No. 10 2008 047 303.0, filed Sep. 16, 2008, the contents of such applications being incorporated by reference herein.
FIELD OF THE INVENTION
The invention relates to a pulsation damping capsule, in particular for pulsation damping in electronically regulated vehicle brake systems or other types of pulsation damping applications.
BACKGROUND OF THE INVENTION
In particular, electronically regulated vehicle brake systems have a hydraulic assembly comprising a receiving body with electrohydraulic valves, with at least one hydraulic pump, and with channels for connecting the pump to at least one hydraulic consumer, a pulsation damping unit being provided between a pressure medium volume (THZ/container, low pressure accumulator) and a suction side of the pump or between a pressure side of the pump and the hydraulic consumer. Eccentric-driven radial piston pumps are mostly used. Millions of said hydraulic assemblies are in use.
Each piston displacement during an eccentric revolution can be divided in an extremely simplified manner into a suction stroke (0−n) and into a pressure stroke (n−2n). Because in each case liquid columns are accelerated but also retarded, this leads on the suction side and also on the pressure side to largely sinusoidal instantaneous pressure profiles which can be changed in details as a function of the concrete embodiment or else can be superimposed. In order to compensate for undesired effects of the instantaneous pressure profiles which fluctuate because of their principle, a pulsation damping unit is provided.
For example, it is known from DE 34 14 558, which is incorporated by reference, to use a diaphragm damper with a metal diaphragm for pulsation damping. Conventional diaphragm dampers with a clamped elastomer diaphragm can suffer from the disadvantage that they are subject to wear, with the result that their effect decreases over the length of the service life. The spring properties are dependent on how quickly the loading takes place (dynamic hardening). As a result, they suffer from nonlinear behavior.
DE 10 2005 028 562 A1, which is incorporated by reference, has disclosed a braking hydraulic assembly comprising a hermetically closed metal hollow body for damping purposes.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a pulsation damping apparatus which is dimensioned suitably for the loading, can also be produced simply, is resistant to high pressure and the pulsation damping action of which can be adapted particularly simply to the prevailing boundary conditions.
The object is achieved in principle by virtue of the fact that a hydraulic branch which is afflicted by pulsation is assigned a defined elasticity which makes it possible to accumulate pressure medium. According to one further independent solution of the problem, a preassembled pulsation damping module is proposed containing a bundle with a plurality of identical pulsation damping capsules. The pulsation damping capsule advantageously has a quasilinear, elastic behavior within a predefined functional pressure range which can reach, for example, as far as approximately 60 bar. Above this predefined functional range, the pulsation damping capsule behaves neutrally as it were, by there being a quasiconstant behavior.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. Included in the drawings is the following figures:
FIG. 1 diagrammatically and partially shows an electrohydraulic vehicle brake system,
FIG. 2 shows a pulsation damping capsule in section in the unloaded state and on an enlarged scale,
FIG. 3 shows a pulsation damping capsule as in FIG. 1 , but in the loaded state,
FIG. 4 shows another embodiment of the pulsation damping capsule in section,
FIG. 5 shows another embodiment of the pulsation damping capsule with structuring, on an enlarged scale and in section,
FIG. 6 shows a perspective view of the pulsation damper capsule according to FIG. 5 on a reduced scale,
FIG. 7 partially shows a pulsation damping capsule as in FIG. 5 ; with clarification of mechanical stresses,
FIG. 8 shows a partial section through a hydraulic receiving body with a pulsation damping chamber and a plurality of inserted pulsation damping capsules,
FIG. 9 shows a diagram for forming an assembled combination (stack) of a plurality of pulsation damping capsules with the use of holding means,
FIG. 10 shows a perspective view of a combination of a plurality of pulsation damping capsules,
FIG. 11 shows a perspective view of a combination of a plurality of pulsation damping capsules with modified holding means,
FIG. 12 shows a perspective view of a combination of a plurality of pulsation damping capsules with modified holding means,
FIG. 13 shows a perspective view of a combination of a plurality of pulsation damping capsules with modified holding means, and
FIGS. 14 , 15 in each case diagrammatically (and not to scale) show further embodiments of a pulsation damping capsule in section, and
FIG. 16 shows a partially diagrammatic comparison of the requirements and the actual pressure volume behavior of different embodiments of pulsation damping capsules.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In a very diagrammatically simplified manner and with the omission of details and electrohydraulic valves, FIG. 1 illustrates an electronically regulated vehicle brake system 1 having a motor/pump assembly 2 with a pump P, comprising a pressure medium inlet E and a pressure medium outlet A, a damping apparatus 3 being provided in connection with the pressure medium outlet A, containing a plurality of damping means 4 , 5 , 6 , 7 , 8 connected in a cascade with the participation of at least one damping chamber. As diagrammatically illustrated, the pressure medium outlet A can be connected to a main cylinder 9 (THZ) or to a wheel brake 10 depending on the required function. The damping means 4 - 8 are arranged in principle together with the pump P in a common receiving body 35 . The different damping means 4 , 5 , 6 , 7 , 8 which are shown symbolically by pictograms comprise by way of example one or more damping chambers, orifices and a symbolically illustrated elasticity 4 , 5 containing one or more pulsation damping capsules 11 , 11 ′, 11 ″ or pulsation damping cells which have such a compressibility that a defined hydraulic volume can be received within a damper chamber.
FIG. 2 shows in detail a pulsation damping capsule 11 for use within a hydraulically loaded pulsation damping chamber 12 . The pulsation damping capsule 11 comprises a metal diaphragm housing 15 which is joined in a hermetically sealed manner from two, preferably concave, half shells 13 , 14 . Although the half shells are formed without the removal of material, a hardenable, stainless metal material is advantageously used, such as, in particular, spring steel of the type 1.4568 with a wall thickness of only approximately a few tenths of a millimeter (by way of example a wall thickness of approximately 0.1 mm). The thin diaphragm which is formed produces a fatigue-resistant, hermetically sealed inner space 16 which is separated from the surrounding pressure means of the pulsation damping chamber 12 , which pressure means usually pulsates at a low frequency (excitation frequency approximately less than 33 Hz).
The half shells 13 , 14 are connected to one another along a circumferential seam 17 with a material to material fit in such a way that a pulsating pressure means brings about an elastic compression or expansion of the pulsation damping capsule 11 , under the action of which the inner space 16 is reduced in size or enlarged. As a result, the pulsation damping chamber 12 which is filled with at least one pulsation damping capsule serves to achieve a largely linearly growing pressure means volume uptake V up to approximately a maximum of 400 mm 3 with a rising pressure means pressure p a within a predefined pressure working range according to FIG. 16 . To this end, an overview of the different targets and the different, concrete measured results (actual) with quadruple, sextuple or octuple arrangements (stacks) of the pulsation damping capsules can be gathered from FIG. 16 . The predefined pressure working range, in other words the operating damping range, always extends as far as approximately 60 bar pressure means pressure p a . Because, however, the pressure means pressure p a generated within vehicle brake systems can grow as far as above approximately 200 bar, a constant volume uptake is required above the defined, upper limit of the provided pressure working range, without overshoots being able to cause irreversible damage. This is achieved substantially by virtue of the fact that a further volume uptake is ended in a defined manner by an integrated stop function.
Each half shell 13 , 14 is preferably configured in a bowl-like manner with a diaphragm-like bottom 18 , 19 and with a wall 20 , 21 which is angled away approximately at a right angle from the bottom 18 , 19 . In each case two identically shaped half shells 13 , 14 are laid with their wall 20 , 21 onto one another immediately directly, and mirror-symmetrically end to end. According to FIG. 2 , the circumferential seam 17 which forms the outer circumference is provided for the hermetic material to material connection of the half shells 13 , 14 . As can be seen, the circumferential seam 17 does not protrude substantially in the radial direction beyond the wall 20 , 21 , but rather is inserted substantially completely smoothly into the course of the wall 20 , 21 .
The refinement according to FIG. 4 differs from the preceding proposal in that each half shell 22 , 23 has an integrally formed flange section 24 , 25 which is angled away substantially at a right angle from the wall 20 , 21 and such that it points radially to the outside. The circumferential seam 17 is placed from the radial outside between the two separate flange sections 24 , 25 . As a result of this measure, the welded seam is placed in a particularly protected manner with regard to alternating loading and, in particular, damaging tensile loadings. Furthermore, it can be seen from FIG. 4 and from the further FIGS. 5-13 that the half shells 22 , 23 are provided, particularly in the region of the base 18 , 19 , with a profiling, in particular with a rotationally symmetrical, wave-shaped profiling. In contrast to the embodiments according to FIGS. 4 to 8 , the wave shape of the profiling can be configured according to a modified embodiment according to FIG. 14 in such a way that they nestle as far as possible in one another ( FIG. 14 ) for the largely complete compression of a pulsation damping capsule 11 . To this end, in each case one wave crest Wb of an upper half shell 13 is assigned a wave crest wb of a lower half shell 14 and vice versa (wave troughs WT/wt). A further special feature comprises the fact that the half shells 13 , 14 ; 22 , 23 can have different diameters, with the result that in each case one of the half shells 13 , 14 ; 22 , 23 is as it were inserted into a half shell of greater diameter and, as a result, is as it were preliminarily positioned for a production process, without a separate holding apparatus. In a comparable manner with the embodiment according to FIG. 4 , this results in placing of the circumferential seam 17 which is particularly suitable for loading. The wall 20 , 21 is oriented uniformly and is angled off at a right angle from the bottom 18 , 19 , and is provided with an axially directed circumferential seam 17 . This design has the advantage that the uniformly angled away wall 20 , 21 makes it possible to insert a pulsation damping capsule fixedly into a hole 36 of corresponding dimensions by means of a resilient clamping action, the circumferential seam being protected against damage by a pressing in operation. Radial pressure means recirculation is made possible by it being possible for separate channels to be provided in the hole 36 from the receiving body 35 .
As has been explained briefly, an application in an electronically regulated vehicle brake system requires in principle a particularly adapted pressure/volume uptake behavior of the damping apparatus 3 . In this context, it can be required that a volume uptake in relation to the prevailing pressure initially increases linearly as the pressure increases, and that this volume uptake remains constant above a predefined volume uptake. For this purpose, each pulsation damping capsule 11 has at least one integrated means which is suitable for limiting the extent of an elastic compression. In other words, the integrated means which can be defined by the shape of the shells themselves, that is to say without separate components, ensures that no further compression of the pulsation damping capsule/cell occurs, with the result that deformation and volume uptake are limited mechanically (kept constant) above defined pressures.
According to one preferred variant, the integrated means is configured as an integrated stop means, each inner space-side bottom 18 , 19 being configured for forming the integrated stop means in the meaning of a stop face 26 , 27 . The outlay on apparatus and production technology is minimized by the bottom 18 , 19 fulfilling as it were a double function which comprises the fact that not only a hermetic inner space boundary, but also a limiting of the volume uptake is achieved by immediately direct, metallic contact of the adjacent bottoms 18 , 19 .
In a modification of an immediately direct stop function of two immediately directly adjacent bottoms 18 , 19 , there can be provision according to another preferred solution for an incompressible medium to be provided as integrated means and, additionally to this, a compressible filling element 28 , for example made from elastomer material, in the inner space 16 of the damping capsule 11 , which filling element 28 can likewise have a structuring, preferably wave crests and wave troughs, congruently with respect to an adjacent, structured bottom, in particular structured in a wave shape. If a completely incompressible filling element 28 or a completely incompressible medium is provided, the inner space 16 should be filled only partially with it, in order that there is compressibility for volume accumulation in another way. If, in contrast, there is a compressible filling of an elasticity which is preset in a defined manner, the inner space 16 can certainly be filled completely.
In order to set the predefined pressure/volume behavior, and also in order to avoid an impermissible deformation or loading of the half shells 13 , 14 ; 22 , 23 , an unstructured filling element 28 for supporting the wall 20 , 21 can bear substantially completely against the half shells 13 , 14 ; 22 , 23 in this region. Further faces of the filling element 28 are provided at a spacing from the bottom 19 , 20 , with the result that the bottom 19 , 20 can compress elastically as it were. The stop faces 29 , 30 on the filling element 28 which are assigned to the stop faces 26 , 27 serve to limit this elastic deformation.
In principle, the filling element 28 can have one or more recesses 31 which in principle are configured as a through hole parallel to the longitudinal axis, in order for it to be possible to assist a medium uptake or a deformation of the filling element 28 itself. The filling element 28 is advantageously configured metallically, from rubber or plastic, and is preassembled as an insert between the half shells 13 , 14 ; 22 , 23 . This can be effected by the filling element 28 being stitched or fastened fixedly to a half shell 13 , 14 ; 22 , 23 in such a way that rattling noise is avoided. The same is otherwise also true for pulsation damping capsules 11 which are adjacent to one another, and for the ratio between pulsation damping capsules 11 and receiving body 35 .
The result tendentially of the given capsule construction is that the edge region makes comparatively low volume uptake possible, whereas maximum elastic deformation predominantly occurs in the center of the bottom of the half shells. The following measures serve to improve the entire volume uptake as a result of an improvement in the edge-side elasticity. To this end, in one embodiment of a pulsation damping capsule 11 with a filling element 28 ′ of wave-shaped structure according to FIG. 15 , said filling element 28 ′ is configured such that it is segmented into at least two parts 28 a , 28 b which can be displaced parallel to one another, in such a way that tolerances of adjacent components, in particular tolerances in the wave structure of adjacent components and/or during the elastic compression operation of the bottoms 18 , 19 , can be compensated for. A further advantage comprises the fact that the edge-side decoupling (omission of the clamping of the filling element 28 ′, which clamping is fixed on the edge side) brings about a significantly increased volume uptake. As a result, the concrete illustration also differs from the above-described embodiments as a result of the bottoms 18 , 19 of wave-shaped structure with the use of a spacing element placed in between, namely a cylindrical ring 36 which in principle can be formed either from metal material or, in the sense of a further spring element, from elastomer material, which further increases the volume uptake of the pulsation damping capsule 11 . The entire structure can be joined together by two welded circumferential seams. Play is provided in the radial direction between the outer circumference of the filling element 28 ′ or its parts 28 a , 28 b and the ring 36 , with the result that the filling element 28 ′ can be adapted to the bottoms 18 , 19 for optimum support.
In a further modification of a pulsation damping capsule 11 , there can be provision for the inner space 16 to be provided with a vacuum, with an air or gas filling, or with a liquid for the purpose of configuring the predefined pressure/volume behavior.
Further embodiments of the invention comprise a plurality of identically configured pulsation damping capsules 11 , 11 ′, 11 ″ being arranged together within a pulsation damping chamber 12 . Here, it is particularly advantageous as an alternative to loose placing of the individual pulsation damping capsules 11 , 11 ′, 11 ″ within the pulsation damping chamber 12 if a grouping or bundling of a plurality of identical pulsation damping capsules 11 , 11 ′, 11 ″ is provided, with the result that as it were only a preassembled module is to be inserted into the pulsation damping chamber 12 , and that each bundle has at least one holding means 32 which is provided for the directed securing and placing of the pulsation damping capsules 11 , 11 ′, 11 ″. It is a basic concept of an arrangement planned in this way to provide a defined spacing between the pulsation damping capsules 11 , 11 ′, 11 ″, which spacing improves ventilation of the brake system. The unit can be formed with the addition of a hole closure for pulsation damping chamber 12 as in FIG. 8 .
Each holding means 32 is arranged integrally with or separately from the pulsation damping capsules 11 , 11 ′, 11 ″. It is generally possible that the holding means 32 is connected with a material to material fit and/or nonpositively to one or to a plurality of pulsation damping capsules 11 , 11 ′, 11 ″. Each holding means 32 ensures a cohesion between the pulsation damping capsules 11 , 11 ′, 11 ″ which are joined together. In this context, it is possible to configure each holding means 32 as a metallic binding which is made from sheet metal and/or wire and is guided overall around all the cells to be bundled.
A gradual modification of this principle comprises the fact that holding means 32 comprise largely strip-shaped sheet metal material with a plurality of receptacles 33 which act, in particular, on the flange section 24 of the pulsation damping capsules 11 , 11 ′, 11 ″, as is apparent from FIGS. 11 and 12 . In this way, it is ensured that the individual pulsation damping capsules 11 , 11 ′, 11 ″ are arranged at a defined spacing from one another, which simplifies a ventilation and a downstream pressure means filling of a receiving body 35 .
Furthermore, it is conceivable that each holding means 32 is provided as a tubular body which is slotted to as great an extent as possible and has receptacles 34 which act radially on the outside for the pulsation damping capsules 11 , 11 ′, 11 ″, with the result that the latter are placed in a defined manner at a predefined regular spacing from one another. Holding means 34 of this type can advantageously be configured from elastic plastic material, in order to make elastic assembly or dismantling possible, as is apparent from FIGS. 9 and 10 .
It is advantageous in principle to provide a plurality of identically configured holding means 32 , in order to achieve an economical effect of quantity.
In a further refinement of the present basic concept of a modular adaptation of a damping characteristic, it can be appropriate and required to add an additional spring element, such as, in particular, an individual half shell, to one or more pulsation damping capsules 11 , 11 ′, 11 ″, without departing from the essence of the invention. It goes without saying that this separate half shell, just like the remaining pulsation damping capsules 11 , 11 ′, 11 ″, may be a constituent part of a preassembled grouping which can be handled with one hand, for simplifying the assembly in the receiving body 35 .
Although the invention has primarily been explained using the example of an application in an electronically regulated vehicle brake system, other types of applications are possible without departing from the core concept of the invention. | A pulsation damping capsule including at least one hermetically joint-sealed metal membrane housing made of at least two preferably concave hemispheres, the housing being provided for separating an inner space from a surrounding pressure medium, wherein the hemispheres are connected together along a peripheral seam firmly bonded such that the pulsation damping capsule can be compressed and expanded as an energy accumulator with spring elasticity due to the effect of the pressure medium. A pulsation damping device is provided which is both dimensioned to withstand stresses and is simple to produce, the pulsation damping effect of which can be tailored especially easily to the existing conditions. Further disclosed is a pulsation damping module for housing a plurality of pulsation damping capsules. | 1 |
BACKGROUND
Technical Field
The present invention relates to a terminal apparatus and a communication method thereof.
Description of the Related Art
In the uplink of the 3rd Generation Partnership Project Long Term Evolution (3GPP LTE), single carrier transmission is performed to maintain a low cubic metric (CM). More specifically, in the presence of data signals, the data signals and control information are time multiplexed and transmitted in a physical uplink shared channel (PUSCH). The control information includes response signals (positive/negative acknowledgments (ACK/NACK), hereinafter called “ACK/NACK signals”) and channel quality indicators (hereinafter called the “CQIs”). Data signals are divided into code blocks (CB), and a cyclic redundancy check (CRC) code is added to each code block for error correction.
ACK/NACK signals and CQIs have different allocation methods. (See Non-Patent Literatures 1 and 2, for example). More specifically, ACK/NACK signals are allocated in parts of a data signal resource by puncturing parts of the data signals (4 symbols) mapped to the resource adjacent to Reference Signals (RSs) (i.e., overwriting the data signals with the ACK/NACK signals). In contrasts, CQIs are allocated over entire sub-frames (2 slots). Since the data signals are allocated in resources other than the CQI allocated resource, no CQIs are punctured (see FIG. 1 .) The reasons for the difference in allocation are as follows: the allocation or non-allocation of an ACK/NACK signal depends on the presence or absence of data signals in downlink. In other words, it is more difficult to predict the occurrence of ACK/NACK signals than it is to predict that of CQIs; hence, puncturing capable of allocating the resource of a suddenly occurring ACK/NACK signal is used during mapping of ACK/NACK signals. Meanwhile, the timing of CQI transmission (i.e., sub-frames) is predetermined based on notification information, which allows the determination of allocation of data signal and CQI resources. Since ACKNACK signals are important information, they are assigned to symbols in the vicinity of pilot signals, which have high estimation accuracy of transmission paths, thereby reducing ACK/NACK signal errors.
A modulation and coding rate scheme (MCS) for data signals in uplink is determined by a base station apparatus (hereinafter called the “base station” or “eNB”) based on the channel quality of the uplink. An MCS for control information in the uplink is determined by adding an offset to the MCS for data signals (see Non-Patent Literature 1, for example). More specifically, since control information is more important than data signals, the MCS for control information is set to a lower transmission rate than the MCS for data signals. This guarantees high-quality transmission of control information.
For example, in the 3GPP LTE uplink, if control information is transmitted in a PUSCH, the amount of resource assigned to the control information is determined based on a coding rate indicated in the MCS for data signals. More specifically, as shown in equation 1 below, the amount of the resource Q assigned to the control information is obtained by multiplying the inverse of the coding rate of data signal by an offset.
[
1
]
Q
=
⌈
(
O
+
P
)
·
M
SC
PUSCH
-
initial
·
N
symb
PUSCH
-
initial
·
β
offset
PUSCH
∑
r
=
0
C
-
1
K
r
⌉
(
Equation
1
)
With reference to equation 1, 0 indicates the number of bits in control information (i.e., ACK/NACK signal or CQI) and P indicates the number of bits for error correction added to the control information (for example, the number of bits in CRC and in some cases, P=0). The total of O and P (O+P) indicates the number of bits in uplink control information (UCI). M SC PUSCH-initial , N symb PUSCH-initial , C and K r indicate the transmission bandwidth for PUSCH, the number of symbols transmitted in the PUSCH per unit transmission bandwidth, the number of code blocks into which data signals are divided, and the number of bits in each code block, respectively. UCI (i.e., control information) includes ACK/NACK, CQI, a rank indicator (RI), which indicates rank information, and a precoding matrix indicator (PMI), which provides precoding information.
With reference to equation 1, (M SC PUSCH-initial ·N symb PUSCH-initial ) indicates the amount of transmission data signal resources, ΣK r indicates the number of bits in a single data signal (i.e., the total number of bits in code blocks into which the data signal is divided). Accordingly, ΣK r /(M SC PUSCH-initial ·N Symb PUSCH-initial ) represents a value that depends the coding rate of the data signal (hereinafter, called “coding rate”). The (M SC PUSCH-initial ·N Symb PUSCH-Initial )/ΣK r Shown in Equation 1 Indicates the Inverse of the coding rate of data signal (i.e., the number of resource elements (RE: resource composed of one symbol or one sub-carrier) used to transmit one bit). β offset PUSCH indicates the amount of offset by which the above-mentioned inverse of the coding rate of data signal is multiplied, and is reported from a base station to each terminal apparatus (hereinafter, called the “terminal” or UE) via upper layers. More specifically, a table indicating candidates of the amounts of offset β offset PUSCH is defined for each part of control information (i.e., ACK/NACK signal and CQI). For example, a base station selects one amount of offset β offset PUSCH from the table (for example, see FIG. 2 ) containing candidates for the amount of offset β offset PUSCH defined for ACK/NACK signal and then notifies a terminal of a notification index corresponding to the selected amount of offset. As is evident from the term “PUSCH-initial,” (M SC PUSCH-initial ·N symb PUSCH-initial ) represents the amount of transmission resource for the initial transmission of a data signal.
The standardization of 3GPP LTE-Advanced, which provides higher-speed transmission than 3GPP LTE, has started. The 3GPP LTE-Advanced system (hereinafter, may be called “LTE-A system”) follows the 3GPP LTE system (hereinafter, called “LTE system”). In 3GPP LTE-Advanced, base stations and terminals that can communicate in a wideband frequency range of 40 MHz or higher will be introduced to achieve downlink transmission rates of up to 1 Gbps.
In an LTE-Advanced uplink, the use of single user multiple input multiple output (SU-MIMO) transmission in which a single terminal transmits data signals in a plurality of layers has been studied. In the SU-MIMO communications, data signals are generated in a plurality of code words (CWs), each of which is transmitted in different layers. For example, CW#0 is transmitted in layers #0 and #1, and CW#1 is transmitted in layers #2 and #3. In each CW, a data signal is divided into a plurality of code blocks and CRC is added to each code block for error correction. For example, a data signal in CW#0 is divided into five code blocks and a data signal in CW#1 into eight code blocks. The “code word” can be regarded as a unit of data signals to be retransmitted. The “layer” is a synonym of a stream.
Unlike the above-mentioned LTE-A system, the LTE systems disclosed in the above-mentioned Non-Patent Literatures 1 and 2 assume the use of the non-MIMO transmission in uplink. In the non-MIMO transmission, a single layer is used at each terminal.
In the SU-MIMO transmission, control information is transmitted in a plurality of layers in some cases, and it is transmitted in one of the plurality of layers in other cases. For example, in an LTE-Advanced uplink, allocation of an ACK/NACK signal in a plurality of CWs and of a CQI in a single CW has been studied. More specifically, since an ACK/NACK signal is the most important information in all parts of control information, the same ACK/NACK signal is allocated in all the CWs (i.e., the same information is assigned to all layers (rank-1 transmission)), thereby reducing inter-layer interference. The same ACK/NACK signals transmitted in a plurality of CWs (i.e., space-division multiplexed) are combined into a single part of information on a transmission path, thereby eliminating the need for the receiving side (base station) to separate the ACK/NACK signals transmitted in a plurality of CWs. Accordingly, inter-layer interference that may occur on the receiving side during the separation does not occur. Thus, high receiving quality can be achieved. Note that the description below assumes that the control information is an ACK/NACK signal and allocated in two CWs (CW#0 and CW#1).
CITATION LIST
Non-Patent Literatures
NPL1
TS36.212 v8.7.0, “3GPP TSG RAN; Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and channel coding”
NPL2
TS36.213 v8.8.0, “3GPP TSG RAN; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Layer Procedure”
BRIEF SUMMARY
Technical Problem
In the SU-MIMO communications, when transmitting control information in a PUSCH, the amount of the resource required to allocate control information (ACK/NACK signals) is determined based on the coding rate of one of the two CWs, just as in the LTE system (for example, Non-Patent Literature 1). For example, as shown in equation 2 below, the coding rate r CW#0 of CW#0 of the two CWs (i.e., CW#0 and CW#1) is used to determine the amount of the resource Q CW#0 required to assign control information in each layer.
[
2
]
Q
CW
#0
=
⌈
(
O
+
P
)
×
1
r
CW
#0
×
β
offset
PUSCH
/
L
⌉
(
Equation
2
)
In equation 2, L indicates the total number of layers (the total number of layers to which CW#0 and CW#1 are assigned). In equation 2, as in equation 1, the amount of the resource required to allocate control information in each layer is determined by multiplying the inverse (1/r CW#0 ) of the coding rate r CW#0 by an offset amount β offset PUSCH and then dividing the result by the total number of layers L. A terminal uses the amount of the resource Q CW#0 determined in accordance with equation 2 to transmit CW#0 and CW#1 assigned to the layers (i.e., L layers).
In this case, however, when CW#0 and CW#1 are combined in the base station, there is a concern that the reception quality of control information after the combination may be poor and fail to meet a requirement.
CW#0, for example, is transmitted using the amount of the resource Q CW#0 which is determined based on the coding rate r CW#0 of CW#0, that is, the amount of resource appropriate for CW#0. Accordingly, control information allocated in CW#0 is likely to meet required reception quality. In contrast, CW#1 is transmitted using the amount of the resource Q CW#0 which is determined based on the coding rate r CW#0 of CW#0 (that is, the other CW). Thus, control information allocated in CW#1 may degrade in the reception quality if the layer to which CW#1 is allocated has a poor transmission path environment.
As shown in FIG. 3 , for example, CW#0 is allocated in layer #0 and layer #1 and CW#1 is allocated in layer #2 and layer #3. A description is given of a case where the coding rate of CW#0 is higher than the coding rate of CW#1. To put it differently, the amount of resource required for the control information allocated in CW#0 is smaller than that required for the control information allocated in CW#1.
In layers #0 and #1, control information allocated in CW#0 can meet the reception quality required by each CW (i.e., reception quality required for control information for the LTE system/the number of CWs). In contrast, in layers #2 and #3, the control information allocated in CW#1 has an amount of resource determined based on CW#0; thus, the amount of resource to meet the required reception quality runs short, thus failing to meet the reception quality required for each CW. Thus, a combination of the control information allocated in CW#0 and CW#1 may result in a lower reception quality than that required for all the CWs (i.e., reception quality required for control information in the LTE system).
Accordingly, it is an object of the present invention to provide a terminal capable of preventing the degradation of reception quality of control information even in a case of adopting the SU-MIMO transmission method, and also to provide a communication method thereof.
Solution to Problem
A first aspect of the present invention provides a terminal apparatus that transmits two code words to which control information is allocated, in a plurality of different layers, the apparatus including: a determination section that determines the amount of resource of the control information in each of the plurality of layers; and a transmission signal generating section that generates a transmission signal through modulation of the control information using the amount of the resource and allocation of the modulated control information to the two code words, in which the determination section determines the amount of the resource based on a lower coding rate of the coding rates of the two code words, or the average of the inverses of the coding rates of the two code words.
A second aspect of the present invention provides a communication method including: determining an amount of resource of control information in each of a plurality of different layers in which two code words are transmitted, the control information being allocated in the two code words; modulating the control information using the amount of the resource; and allocating the modulated control information in the two code words to generate a transmission signal, in which the amount of the resource is determined based on a lower coding rate of the coding rates of the two code words, or the average of the inverses of the coding rates of the two code words.
Advantageous Effects of Invention
The present invention can prevent the degradation of reception quality of control information even in a case of adopting the SU-MIMO transmission method.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 shows a conventional allocation of ACKs/NACKs and CQIs;
FIG. 2 is a diagram provided for describing a table containing candidates for an offset amount in the conventional case;
FIG. 3 is a diagram provided for describing a technical problem;
FIG. 4 is a block diagram showing the configuration of a base station according to Embodiment 1 of the present invention;
FIG. 5 is a block diagram showing the configuration of a terminal according to Embodiment 1 of the present invention;
FIG. 6 shows exemplary correction factors according to Embodiment 1 of the present invention;
FIG. 7 shows exemplary correction factors according to Embodiment 2 of the present invention;
FIG. 8 shows exemplary correction factors according to Embodiment 2 of the present invention;
FIG. 9 shows a technical problem in the case where the number of layers differs between initial transmission and re-transmission according to Embodiment 3 of the present invention; and
FIG. 10 shows a process for determining the amount of resource of control information according to Embodiment 3 of the present invention.
DETAILED DESCRIPTION
Embodiments of the present invention will be hereinafter described in detail with reference to the accompanying drawings. In the embodiments, the same components are given the same reference numerals without redundant descriptions.
Embodiment 1
Overview of Communication System
In the following description, a communications system including base station 100 and terminal 200 as described hereinafter is an LTE-A system, for example. Base station 100 is an LTE-A base station, and terminal 200 is an LTE-A terminal, for example. The communication system is assumed to be a frequency division duplex (FDD) system. Terminal 200 (LTE-A terminal) can be switched between non-MIMO and SU-MIMO transmission modes.
(Configuration of Base Station)
FIG. 11 is a block diagram showing the configuration of base station 100 according to this embodiment.
In base station 100 as shown in FIG. 4 , setting section 101 sets control parameters related to resource allocation for control information (including at least ACK/NACK signals or CQIs) transmitted in an uplink data channel (PUSCH) used to communicate with a terminal for which the control parameters are set based on the transmitting and receiving capability of the terminal (i.e., UE capability) or the state of the transmission path. The control parameters include, for example, an amount of offset (for example, an amount of offset β offset PUSCH as shown in equation 2) used in allocation of resource of control information transmitted by the terminal for which the control parameters are set. Setting section 101 outputs setting information including the control parameters to coding and modulating section 102 and ACK/NACK and CQI receiving section 111 .
For terminals performing the non-MIMO transmission, setting section 101 generates MCS information for a single CW (or transport block) and allocation control information including resource (or resource block (RB)) allocation information, while for terminals performing SU-MIMO transmission, setting section 101 generates allocation control information including MCS information for the two CWs (or transport blocks), or the like.
The allocation control information generated by setting section 101 includes uplink allocation control information indicating uplink resource (for example, physical uplink shared channel (PUSCH)) to which uplink data of a terminal is assigned, and downlink allocation control information indicating downlink resource (for example, physical downlink shared channel (PDSCH)) to which downlink data addressed to a terminal is assigned. In addition, the downlink allocation control information includes information indicating the number of bits of ACK/NACK signals for the downlink data (i.e., ACK/NACK information). Setting section 101 outputs the uplink allocation control information to coding and modulating section 102 , reception processing sections 109 in reception sections 107 - 1 to 107 -N, and ACK/NACK and CQI receiving section 111 and outputs the downlink allocation control information to transmission signal generating section 104 and ACK/NACK and CQI receiving section 111 .
Coding and modulating section 102 codes and modulates the set information and uplink allocation control information received from setting section 101 , and then outputs the modulated signals to transmission signal generating section 104 .
Coding and modulating section 103 codes and modulates transmission data to be received and then outputs the modulated data signals (for example, PDSCH signals) to transmission signal generating section 104 .
Transmission signal generating section 104 allocates the signals received from coding and modulating section 102 and the data signals received from coding and modulating section 103 to a frequency resource to generate frequency domain signals based on the downlink allocation control information received from setting section 101 . Transmission signal generating section 104 then converts the frequency domain signals into time-waveform signals using inverse fast Fourier transform (IFFT) processing, and adds a cyclic prefix (CP) to the time waveform signals, thereby obtaining orthogonal frequency division multiplexing (OFDM) signals.
Transmitting section 105 performs radio transmission processing (upconversion and digital-analogue (D/A) conversion and/or the like) on the OFDM signals received from transmission signal generating section 104 , and then transmits the signals through antenna 106 - 1 .
Reception sections 107 - 1 to 107 -N are provided to antennas 106 - 1 to 106 -N, respectively. Reception sections 107 include respective radio processing sections 108 and reception processing sections 109 .
More specifically, radio processing sections 108 in respective reception sections 107 - 1 to 107 -N receive radio signals through respective antennas 106 , perform radio processing (downconversion and analog-digital (A/D) conversion and/or the like) on the received radio signals and then output the resulting reception signals to respective reception processing sections 109 .
Reception processing sections 109 remove CP from the reception signals and perform fast Fourier transform (FFT) on the signals to convert the signals into frequency domain signals. Reception processing sections 109 extract uplink signals for each terminal (including data signals and control signals (i.e., ACK/NACK signal and CQI)) from the frequency domain signals based on the uplink allocation control information received from setting section 101 . If the reception signals are space-division multiplexed (that is, a plurality of CWs are used (i.e., on the SU-MIMO transmission)), reception processing sections 109 separate and combine the CWs. Reception processing sections 109 then perform inverse discrete Fourier transform (IDFT) processing on the extracted (or extracted and separated) signals to convert the signals into time domain signals. Reception processing sections 109 output the time domain signals to data reception section 110 and ACK/NACK and CQI receiving section 111 .
Data reception section 110 decodes the time domain signals received from reception processing sections 109 and then outputs the decoded uplink data as reception data.
ACK/NACK and CQI receiving section 111 calculates the amount of uplink resource to which ACK/NACK signals are assigned, based on the setting information (i.e., control parameters), the MCS information for uplink data signals (i.e., MCS information for each CW in the case of the SU-MIMO transmission), and the downlink allocation control information (for example, ACK/NACK information showing the number of bits of ACK/NACK signals for downlink data) received from setting section 101 . For CQIs, ACK/NACK and CQI receiving section 111 further calculates an amount of uplink resource (e.g., PUSCH) to which the CQI is assigned, using information concerning the preset number of bits of a CQI. Based on the calculated amount of resource, ACK/NACK and CQI receiving section 111 then extracts ACK/NACKs or CQIs from each terminal for downlink data (PDSCH signals) from the channel (for example, PUSCH) to which uplink data signals have been assigned.
If the traffic state in cells covered by base station 100 remains unchanged or if the measurement of an average reception quality is needed, control parameters (for example, the amount of offset β offset PUSCH ) to be notified by base station 100 to terminal 200 should preferably be transmitted in an upper layer at a long notification interval (RRC signaling) from a perspective of signaling. Transmitting all or part of these control parameters as broadcast information leads to a reduction in an amount of resource required for the notification. On the contrary, if control parameters need to be dynamically changed in response to the traffic state in cells covered by base station 100 , all or part of these control parameters should preferably be notified in a PDCCH at a short notification interval.
(Terminal Configuration)
FIG. 12 is a block diagram showing the configuration of terminal 200 in accordance with Embodiment 1 of the present invention. Terminal 200 is an LTE-A terminal which receives data signals (downlink data) and transmits an ACK/NACK signal corresponding to the data signals through a physical uplink control channel (PUCCH) or PUSCH to base station 100 . Terminal 200 transmits a CQI to base station 100 in accordance with instruction information notified through a physical downlink control channel (PDCCH).
In terminal 200 shown in FIG. 5 , reception section 202 performs radio processing (down-conversion and analog-digital (A/D) conversion and/or the like) on radio signals received through antenna 201 - 1 (i.e., OFDM signals herein) and outputs the resulting reception signals to reception processing section 203 . The reception signals include data signals (for example, PDSCH signals), allocation control information and upper layer control information including setting information.
Reception processing section 203 removes CP from the reception signals and performs fast Fourier transform (FFT) on the remaining signals to convert the signals into frequency domain signals. Reception processing section 203 then separates the frequency domain signals into upper layer control signals (for example, RRC signaling) including setting information, allocation control information, and data signals (i.e., PDSCH signals), and then demodulates and decodes the separated signals. Reception processing section 203 also checks the data signals for an error, and if the received data contains an error, a NACK signal is generated, and if not, it generates an ACK signal as the ACK/NACK signal. Reception processing section 203 outputs ACK/NACK signals and ACK/NACK information and MCS information in the allocation control information to resource amount determining section 204 and transmission signal generating section 205 , and outputs setting information (for example, control parameters (an amount of offset)) to resource amount determining section 204 , and outputs the uplink allocation control information in the allocation control information (for example, uplink resource allocation results) to transmission processing sections 207 in respective transmitting sections 206 - 1 to 206 -M.
Resource amount determining section 204 determines the amount of resource required to allocate ACK/NACK signals, based on the ACK/NACK information (the number of bits of ACK/NACK signals), MCS information and control parameters (an amount of offset or the like) concerning resource allocation of control information (ACK/NACK signals) received from reception processing section 203 . For CQIs, resource amount determining section 204 determines the amount of resource required to allocate CQIs, based on the MCS information and control parameters (an amount of offset or the like) concerning resource allocation of control information (CQIs) received from reception processing section 203 , and the preset number of bits of a CQI. In the case of the SU-MIMO transmission, where the two CWs (CW#0 and CW#1) are transmitted in a plurality of layers, resource amount determining section 204 determines the amount of resource for each of the plurality of layers, the amount of the resource being allocated to control information (ACK/NACK signals) allocated in the two CWs (CW#0 and CW#1). More specifically, resource amount determining section 204 determines the amount of the resource based on either the lower coding rate of the coding rates of the two CWs or the average of the inverses of the coding rates of the two CWs. Details on methods for determining the amount of the resource required to allocate control information (ACK/NACKs or CQIs) in resource amount determining section 204 is given hereinafter. Resource amount determining section 204 outputs the determined amount of resource to transmission signal generating section 205 .
Transmission signal generating section 205 generates a transmission signal by allocating an ACK/NACK signal (error detection result of downlink data), data signals (uplink data) and CQIs (downlink quality information) in CWs allocated to one or more layers based on the ACK/NACK information (the number of bits of an ACK/NACK signal) and MCS information received from reception processing section 203 .
More specifically, transmission signal generating section 205 first modulates the ACK/NACK signal based on the amount of the resource (i.e., the amount of resource of the ACK/NACK signal) received from resource amount determining section 204 . Transmission signal generating section 205 also modulates the CQI based on the amount of the resource (i.e., the amount of resource of the CQIs) received from resource amount determining section 204 . Transmission signal generating section 205 modulates transmission data using the amount of the resource specified by using the amount of the resource (i.e., CQI resource amount) received from resource amount determining section 204 (the amount of the resource is specified by subtracting the amount of CQI resource from the amount of the resource for each slot).
In the case of non-MIMO transmission, transmission signal generating section 205 generates a transmission signal by allocating the ACK/NACK signal, data signals and CQI that have been modulated using the above-mentioned amount of resource in a single CW. Meanwhile, in the case of SU-MIMO transmission, transmission signal generating section 205 generates a transmission signal by allocating the ACK/NACK signal and data signals that have been modulated using the above-mentioned amount of resource in the two CWs and by allocating the CQI in one of the two CWs. Furthermore, in the case of non-MIMO transmission, transmission signal generating section 205 assigns a single CW to a single layer, and in the case of SU-MIMO transmission, transmission signal generating section 205 assigns the two CWs to a plurality of layers. For example, in the case of the SU-MIMO transmission, transmission signal generating section 205 assigns CW#0 to layer #0 and layer #1 and assigns CW#1 to layer #2 and layer #3.
In the presence of data signals and CQIs to be transmitted, transmission signal generating section 205 assigns the data signals and CQIs to an uplink data channel (PUSCH) by time multiplexing or frequency division multiplexing using a rate matching in one of the plurality of CWs as shown in FIG. 1 . In the presence of data signals and ACK/NACK signals to be transmitted, transmission signal generating section 205 overwrites part of the data signals with ACK/NACK signals in all of the plurality of layers (i.e., puncturing). To put it differently, ACK/NACK signals are transmitted in all the layers. In the absence of data signals to be transmitted, transmission signal generating section 205 assigns CQIs and ACK/NACK signals to an uplink control channel (for example, PUCCH). Transmission signal generating section 205 then outputs the transmission signals thus generated (including ACK/NACK signals, data signals or CQIs) to transmitting sections 206 - 1 to 206 -M.
Transmitting sections 206 - 1 to 206 -M correspond to antennas 201 - 1 to 201 -M, respectively. Transmitting sections 206 include respective transmission processing sections 207 and radio processing sections 208 .
More specifically, transmission processing sections 207 in respective transmitting sections 206 - 1 to 206 -M perform discrete Fourier transform (DFT) to the transmission signals received from transmission signal generating section 205 (i.e., signals corresponding to respective layers) to convert the data signals, ACK/NACK signals and CQIs into frequency domain signals. Transmission processing sections 207 then maps the plurality of frequency components obtained by the DFT processing (including ACK/NACK signals and CQIs transmitted on the PUSCH) to the uplink data channels (PUSCH) based on the uplink resource allocation information received from reception processing section 203 . Transmission processing sections 207 convert the plurality of frequency components mapped to the PUSCH into time domain waveforms and add CP thereto.
Radio processing sections 208 perform radio processing (upconversion and digital-analog (D/A) conversion and/or the like) on the signals to which CP has been added, and then transmit the signals through respective antennas 201 - 1 to 201 -M.
(Operations of Base Station 100 and Terminal 200 )
The operations of base station 100 and terminal 200 having the above-mentioned configurations will be described below. In particular, the method used by resource amount determining section 204 of terminal 200 to determine the amount of the resource required to allocate control information (ACK/NACKs or CQIs) will be described in details. In the following description, the method for determining the amount of the resource in the SU-MIMO transmission, where a plurality of CWs to which control information is allocated are transmitted in a plurality of layers, will be described.
In the following description, terminal 200 (transmission signal generating section 205 ) allocates ACK/NACK signals, which are control information, in the two CWs (i.e., CW#0 and CW#1).
Determination Methods 1 to 5 for determining the amount of the resource of control information are described below.
<Determination Method 1>
In Determination Method 1, resource amount determining section 204 determines the amount of the resource required to allocate control information in each layer based on the lower coding rate of the coding rates of the two CWs to which control information is allocated. More specifically, resource amount determining section 204 determines the amount of the resource required to allocate control information in each layer Q CW#0+CW#1 based on the lower coding rate of the coding rates of CW#0 and CW#1 (coding rate r lowMCS ) in accordance with equation 3.
[
3
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
×
1
r
lowMCS
×
β
offset
PUSCH
/
L
⌉
(
Equation
3
)
With reference to equation 3, O indicates the number of bits in control information and P indicates the number of bits for error correction added to control information (for example, the number of bits in CRC and in some cases, P=0). L indicates the total number of layers (the total number of layers containing CWs).
Resource amount determining section 204 , as shown in equation 3 and as in equation 1, determines the amount of the resource of control information in each layer by multiplying the inverse (1/r lowMCS ) of the coding rate r lowMCS by the amount of offset β offset PUSCH , and then dividing the result by the total number of layers L.
In this manner, the reception quality required by each CW can be ensured in all the layers. More specifically, in the layer containing CW#0 or CW#1 having the lower coding rate (i.e., CW with the coding rate r lowMCS ), the amount of resource Q CW#0+CW#1 determined based on the coding rate r lowMCS , that is, an appropriate amount of resource is used for transmission, thus ensuring the control information allocated in that CW meets the required reception quality. In the layer containing CW#0 or CW#1 having the higher coding rate, the amount of the resource Q CW#0+CW#1 determined based on the coding rate r lowMCS (that is, the coding rate of the other CW) is used for transmission, but that amount is equal to or more than the appropriate amount of resource. Thus, the control information allocated in that CW can sufficiently meet the required reception quality.
As shown above, in accordance with Determination Method 1, resource amount determining section 204 uses a CW with the lower coding rate of the coding rates of the plurality of CWs to determine the amount of the resource of control information in each layer. In other words, resource amount determining section 204 uses a CW assigned to a layer in a poor transmission path environment among a plurality of CWs to determine the amount of the resource of control information in each layer, thus ensuring that required reception quality is sufficiently met in all the CWs, including the CW assigned to a layer in a poor transmission path environment. Thus, base station 100 can meet reception quality required by all the CWs (i.e., reception quality required by control information in an LTE system). Accordingly, by combining CW#0 and CW#1 into control information, base station 100 can ensure that the combined control information can meet the required reception quality, and prevent the degradation of reception quality of the control information.
<Determination Method 2>
In Determination Method 2, resource amount determining section 204 determines the amount of the resource of control information in each layer based on the average of the inverses of the coding rates of the two CWs. More specifically, resource amount determining section 204 determines the amount of the resource Q CW#0+CW#1 of control information in each layer in accordance with equation 4 below.
[
4
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
×
1
r
CW
#0
+
1
r
CW
#1
2
×
β
offset
PUSCH
/
L
⌉
(
Equation
4
)
In equation 4, r CW#0 indicates the coding rate of CW#0 and r CW#1 indicates the coding rate of CW#1.
Resource amount determining section 204 , as shown in equation 4 and as in equation 1, determines the amount of the resource of control information in each layer by multiplying an average of the inverse (1/r CW#0 ) of the coding rate r CW#0 and the inverse (1/r CW#1 ) of the coding rate r CW#1 by an amount of offset β offset PUSCH and dividing the result by the total number of layers L.
One bit of the control information allocated in CW#0 is coded into (1/r CW#0 ) bit. Likewise, one bit of the control information allocated in CW#1 is coded into (1/r CW#1 ) bit. In other words, the average of the number of bits obtained by coding one bit of the control information in each CW ((1/r CW#0 )+(1/r CW#1 )/2) corresponds to the average of the number of bits appropriate for combining CW#0 and CW#1. Thus, the average of the inverses of the CW coding rates ((1/r CW#0 )+(1/r CW#1 )/2) equals the inverse of the coding rate of a combined CW obtained by combining CW#0 and CW#1.
In accordance with Determination Method 1 (equation 3), the amount of resource is determined based on the lower coding rate of the coding rates of the two CWs (i.e., CW#0 and CW#1). This means that an appropriate amount of resource is determined for the layer containing a CW with the lower coding rate among CW#0 and CW#1, while an amount of resource equal to or more than an appropriate amount of resource is determined for the layer containing the other CW (i.e., CW with the higher coding rate), which results in wasteful use of resource.
In contrast, in accordance with Determination Method 2, resource amount determining section 204 determines the amount of resource of control information in each layer based on the inverse of the coding rate of a combined CW obtained by combining CW#0 and CW#1 (the average of the inverses of the coding rates of CW#0 and CW#1).
an amount of resource smaller than that determined by Determination Method 1 for the layer containing a CW with a higher coding rate between CW#0 and CW#1 is determined. In other words, Determination Method 2 can reduce more wasteful use of resource than Determination Method 1 for a layer allocated to a CW with the higher coding rate. In contrast, an amount of resource less than an appropriate amount of resource is determined for a layer allocated to a CW having the lower coding rate. As described above, since resource amount determining section 204 determines the amount of the resource such that a combined CW obtained by combining all the CWs can meet required reception quality, base station 100 combines CW#0 and CW#1 and ensures that the combined control information can meet required reception quality.
As described above, in accordance with Determination Method 2, resource amount determining section 204 determines the amount of resource required to assign control information in each layer based on the average of the inverses of the coding rates of the plurality of CWs. This prevents the degradation of reception quality of control information while reducing wasteful use of resources.
<Determination Method 3>
In Determination Method 3, resource amount determining section 204 determines the amount of the resource of control information in each layer based on the inverse of the coding rate of one of the two CWs and a correction factor notified from base station 100 . More specifically, resource amount determining section 204 determines the amount of the resource Q CW#0+CW#1 of control information in each layer in accordance with equation 5 below.
[
5
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
×
1
r
CW
#0
×
β
offset
PUSCH
×
γ
offset
/
L
⌉
(
Equation
5
)
In equation 5, r CW#0 indicates the coding rate of CW#0 and γ offset indicates a correction factor notified from base station 100 as a control parameter.
Resource amount determining section 204 , as shown in equation 5 and as in equation 1, determines the amount of the resource of control information in each layer by multiplying the inverse (1/r CW#0 ) of the coding rate r CW#0 by an amount of offset β offset PUSCH , further multiplying the resulting resource amount by a correction factor γ offset , and dividing the result by the total number of layers L.
An exemplary correction factor γ offset notified from base station 100 is shown in FIG. 6 . Base station 100 selects a correction factor γ offset based on a difference in coding rate between two CW#0 and CW#1 (difference in reception quality) or a coding rate ratio between CW#0 and CW#1 (ratio of reception quality).
More specifically, if the coding rate of a single CW (coding rate r CW#0 of CW#0 in this case) used to determine the amount of the resource of control information is lower than the coding rate of the other CW (coding rate r CW#1 of CW#1 in this case), base station 100 uses a correction factor γ offset of a value less than 1.0 (any of the correction factors for the signaling #A to #C shown in FIG. 6 ).
On the other hand, if the coding rate of a single CW (coding rate r CW#0 of CW#0 in this case) used to determine the amount of the resource of control information is higher than the coding rate of the other CW (coding rate r CW#1 of CW#1 in this case), base station 100 uses a correction factor γ offset exceeding 1.0 (one of correction factors for the signaling #E and #F shown in FIG. 6 ).
The smaller the difference in coding rate between the CWs (difference in reception quality) is, the closer to 1.0 the correction factor γ offset selected by base station 100 is (if there is no difference in coding rate between the CWs (i.e., the rates are identical), the correction factor for signaling #D shown in FIG. 6 (1.0) is selected).
Base station 100 notifies terminal 200 of setting information including control parameters including the selected correction factor γ offset (the signaling number of the correction factor γ offset ) via the upper layers.
As described above, resource amount determining section 204 uses a correction factor γ offset set in accordance with a difference in coding rate (a difference in reception quality) between the two CWs to correct the amount of the resource determined based on the coding rate (inverse) of one of the two CWs.
As shown above, determination of the amount of the resource based on the inverse of the lower coding rate of the coding rates of the two CWs (coding rate r CW#0 of CW#0 in this case) results in setting of an excess amount of resource for the other CW (CW#1 in this case), for example. To cope with this problem, resource amount determining section 204 can reduce the excess use of resource for the other CW (CW#1 in this case) by multiplying the amount of the resource determined based on the inverse of the lower coding rate by a correction factor γ offset of a value less than 1.0. Likewise, determination of the amount of the resource based on the inverse of the higher coding rate of the coding rates of the two CWs results in an insufficient amount of resource for the other CW. To address this problem, resource amount determining section 204 can increase the amount of the resource of the other CW by multiplying the amount of the resource determined based on the inverse of the higher coding rate by a correction factor γ offset of a value exceeding 1.0.
As described above, equation 5 corrects the amount of the resource determined based on the coding rate of one of CWs (coding rate r CW#0 of CW#0 in this case) with a correction factor γ offset set in accordance with a difference in coding rate between the two CWs, thereby allowing the calculation of the amount of the resource based on the two CWs (i.e., required reception quality of a combined CW obtained by combining the two CWs).
To put it differently, resource amount determining section 204 corrects the coding rate (inverse) of one of the two CWs in accordance with the difference in coding rate between the two CWs. More specifically, resource amount determining section 204 adjusts the corrected coding rate such that the coding rate is approximated to the average of the coding rates of the two CWs by adopting a larger correction factor (γ offset ) for the coding rate (i.e., inverse) of one of the two CWs in response to a larger difference in coding rate between the two CWs. Accordingly, the inverse of the corrected coding rate (γ offset /1 CW#0 in equation 5) corresponds to the average of the inverses of the coding rates of the two CWs (i.e., the value to which the corrected coding rate is approximated). Resource amount determining section 204 determines the amount of the resource of control information in each layer based on the average of the inverses of the coding rates of the two CWs (i.e., the inverse of the corrected coding rate (γ offset /r CW#0 in equation 5).
As shown above, in accordance with Determination Method 3, resource amount determining section 204 determines the amount of the resource required to allocate control information in each layer based on the inverse of the coding rate of one CW and a correction factor set in accordance with a difference in coding rate between the two CWs. In this manner, the amount of the resource in consideration of both of the two CWs can be determined, which in turn, prevents the degradation in reception quality of control information while reducing wasteful use of resource.
In accordance with Determination Method 3, even in the case where the coding rate of one of the two CWs (coding rate r CW#0 of CW#0 in equation 5) is extremely low (for example, r CW#0 is infinitely close to 0), assignment of an excessive amount of resource to control information can be prevented by multiplying the amount of the resource calculated based on the coding rate r CW#0 by a correction factor γ offset set in accordance with a difference in coding rate between the two CWs. This means that the correction factor can prevent the assignment of an excessive assignment of resources.
If it is pre-determined that the lower coding rate of the coding rates of the two CWs is used to determine the amount of the resource Q CW#0+CW#1 , instead of the coding rate r CW#0 of CW#0 shown in equation 5, only correction factors γ offset of values equal to 1.0 or lower may be used as candidates. For example, among the candidates for correction factor γ offset in FIG. 6 , only the correction factors γ offset for the signaling #A to #D may be set. This leads to a reduction in the amount of signaling used for notification of the correction factors γ offset .
Likewise, if it is pre-determined that the higher coding rate of the coding rates of the two CWs is used to determine the amount of the resource Q CW#0+CW#1 , instead of the coding rate r CW#0 of CW#0 shown in equation 5, only correction factors γ offset of values equal to 1.0 or higher may be used as candidates. For example, among the candidates for correction factor γ offset in FIG. 6 , only the correction factors γ offset for the signaling #D to #F may be set. This leads to a reduction in the amount of signaling used for notification of the correction factors γ offset .
A plurality of correction factor γ offset candidate tables may be provided and switched depending on whether the coding rate r CW#0 of CW#0 in equation 5 is the lower or higher coding rate of the coding rates of two CWs. For example, if the coding rate r CW#0 of CW#0 in equation 5 is the lower coding rate of the coding rates of the two CWs, a candidate table containing the correction factors γ offset for the signaling #A to #D shown in FIG. 6 may be used. In contrast, if the coding rate r CW#0 of CW#0 in equation 5 is the higher coding rate of the coding rates of the two CWs, a candidate table containing correction factors γ offset for the signaling #D to #E shown in FIG. 6 may be used.
<Determination Method 4>
Determination Method 4 is identical to Determination Method 3 (equation 5) in that the amount of the resource of control information is calculated based on the coding rate (inverse) of one of the two CWs, except for the calculation method of the correction factor.
Hereinafter, Determination Method 4 is described in details.
Since the two CWs to which control information is allocated are combined at base station 100 as described above, focusing on “reception quality of one” of the two CWs, reception quality of (“reception quality of a combined CW”/“reception quality of one of the two CWs”) fold is obtained after combining the two CWs. The “reception quality of a combined CW” is obtained when the two CWs are combined.
To maintain the reception quality required for the entire CWs, the correction factor for the amount of the resource of control information calculated based on the coding rate (inverse) of one of CWs may be set to (“reception quality of one of CWs”/“reception quality of a combined CW”). This ensures the reception quality necessary to maintain the reception quality required by each CW to which control information is allocated at a minimum amount of resource required after combination of the two CWs.
In general, the following relationship holds between the reception quality and the coding rate: The higher the reception quality of a signal is, the higher the coding rate of the signal is. Thus, (“coding rate of one of CWs”/“coding rate of a combined CW”) can be substituted for (“reception quality of one of CWs”/“reception quality of a combined CW”) as a correction factor. The “coding rate of a combined CW” is obtained by combining two CWs.
Resource amount determining section 204 uses equation 6 below to set a correction factor γ offset which is represented by (“coding rate of one of CWs (r CW#0 )”/“coding rate of a combined CW (r CW#0 CW#1 )”). In equation 6, the coding rate r CW#0 of CW#0 of the CW#0 and CW#1 is used as the “coding rate of one of CWs”.
[
6
]
γ
offset
=
coding
rate
of
one
of
CWs
(
r
CW
#0
)
coding
rate
of
a
combined
CW
(
r
CW
#0
+
CW
#1
)
=
r
CW
#0
×
M
CW
#0
SC
PUSCH
-
initial
·
N
CW
#0
symb
PUSCH
-
initial
+
M
CW
#1
SC
PUSCH
-
initial
·
N
CW
#1
symb
PUSCH
-
initial
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
(
Equation
6
)
In equation 6, M CW#0SC PUSCH-initial indicates a PUSCH transmission bandwidth for CW#0, M CW#1SC PUSCH-initial indicates a PUSCH transmission bandwidth for CW#1, N CW#0Symb PUSCH-initial indicates the number of transmission symbols in PUSCH per unit transmission bandwidth for CW#0, and N CW#1Symb PUSCH-initial indicates the number of transmission symbols in PUSCH per unit transmission bandwidth for CW#1. C CW#0 indicates the number of code blocks into which a data signal allocated in CW#0 is divided, C CW#1 indicates the number of code blocks into which a data signal allocated in CW#1 is divided, K r CW#0 indicates the number of bits in each code block in CW#0 and K r CW#1 indicates the number of bits in each code block in CW#1. For example, if CW#0 is assigned to two layers and assigned to 12 transmission symbols and has 12 sub-carriers in each layer, the amount of the resource of CW#0 (M CW#0SC PUSCH-initial ·N CW#0Symb PUSCH-initial ) is 288 (RE). To be more precise, the M CW#0SC PUSCH-initial equals 12 sub-carriers, and the N CW#0Symb PUSCH-initial equals 24 transmission symbols (two layers each have 12 transmission symbols); thus, the amount of the resource of CW#0 (M CW#0SC PUSCH-initial ·N CW#0Symb PUSCH-initial ) is 288 (=12×24). Note that M CW#0SC PUSCH-initial , M CW#1SC PUSCH-initial , N CW#0Symb PUSCH-initial and N CW#1Symb PUSCH-initial represent values at initial transmission.
(M CW#0SC PUSCH-initial ·N CW#0Symb PUSCH-initial +M CW#1SC PUSCH-initial ·N CW#1Symb PUSCH-initial ) shown in equation 6 indicates the total amount of transmission resources of respective data signals in CW#0 and CW#1, and (ΣK r CW#0 +ΣK r CW#1 ) indicates the total number of transmission symbols in a PUSCH (or the total number of bits in CW#0 and CW#1) to which respective data signals in CW#0 and CW#1 (all code blocks) are assigned. Accordingly, (M CW#0SC PUSCH-initial ·N CW#0Symb PUSCH-initial +M CW#1SC PUSCH-initial ·N CW#1Symb PUSCH-initial )/(ΣK r CW#0 +ΣK r CW#1 ) shown in equation 6 indicates the inverse of the coding rate of a combined CW (1/(coding rate of a combined CW (r CW#0+CW#1 ))).
Resource amount determining section 204 assigns the correction factor γ offset shown in equation 6 to, for example, equation 5. Resource amount determining section 204 determines the amount of the resource of control information Q CW#0+CW#1 in each layer in accordance with equation 7 below:
[
7
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
M
CW
#0
sc
PUSCH
-
initial
·
N
CW
#0
symb
PUSCH
-
initial
+
M
CW
#1
sc
PUSCH
-
initial
·
N
CW
#1
symb
PUSCH
-
initial
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
·
β
offset
PUSCH
/
L
⌉
(
Equation
7
)
Resource amount determining section 204 , as shown in equation 7 and as in equation 1, determines the amount of the resource of control information in each layer by multiplying the inverse (1/r CW#0 ) of the coding rate r CW#0 by an amount of offset β offset PUSCH to obtain an amount of resource, multiplying the resulting amount of resource by a correction factor γ offset , and then dividing the result by the total number of layers L.
the result obtained by multiplying the inverse (1/r CW#0 ) of the “coding rate of one of CWs (r CW#0 )” in equation 5 by a correction factor γ offset shown in equation 6 (“coding rate of one of CWs (r CW#0 )”/“coding rate of a combined CW (r CW#0+CW#1 )”) is equivalent to the inverse of the coding rate of a CW obtained by combining CW#0 and CW#1 (1/(coding rate of a combined CW (r CW#0 CW#1 ))). In other words, the inverse of the coding rate of a combined CW (1/(coding rate of a combined CW (r CW#0+CW#1 ))), that is, the average of the inverses of the coding rates of the two CWs can be obtained by correcting the inverse of the coding rate of one of the two CWs (1/r CW#0 ) with a correction factor γ offset (equation 6). Accordingly, resource amount determining section 204 uses the inverse of the coding rate of a combined CW as the average of the inverses of the coding rates of the two CWs to determine the amount of the resource of control information in each layer.
As shown above, in Determination Method 4, resource amount determining section 204 determines the amount of the resource required to allocate control information in each layer based on the inverse of the coding rate of one of CWs, and the correction factor calculated based on the ratio of reception quality (i.e., the ratio of coding rates) between the two CWs. In other words, resource amount determining section 204 uses the ratio between the coding rate (reception quality) of one of CWs and the coding rate (reception quality) of a combined CW obtained by combining the two CWs, that is, the ratio of coding rates (i.e., ratio of reception quality) between the two CWs as a correction factor. This allows resource amount determining section 204 to obtain the reception quality necessary to maintain the reception quality required by each CW to which control information is allocated at a minimum amount of resource required. As shown above, Determination Method 4 can determine the amount of the resource in consideration of both the two CWs, thus preventing the degradation of reception quality of control information without wasteful use of resource.
Furthermore, Determination Method 4 allows terminal 200 to calculate a correction factor based on the coding rates (reception quality) of the two CWs, thus eliminating the need for base station 100 to notify terminal 200 of a correction factor, unlike in Determination Method 3. More specifically, Determination Method 4 can reduce the amount of signaling from base station 100 to terminal 200 , as compared with Determination Method 3.
In Determination Method 4, the denominator of the correction factor γ offset shown in equation 6 indicates the total number of bits in CW#0 and CW#1. Accordingly, even if the coding rate of either CW#0 or CW#1 is extremely low (data size is extremely small), the correction factor γ offset is determined, taking the coding rate of the other CW into account, thereby preventing assignment of an excess amount of resource to the control information.
<Determination Method 5>
If the same control information is transmitted in a plurality of layers at the same time and at the same frequency, that is, if a rank-1 transmission is performed, the amount of the resource allocated to control information transmitted in each of a plurality of layers is equal.
In such a case, resource amount determining section 204 should preferably determine the amount of the resource of control information in each layer based on the number of bits that can be transmitted in the same amount of resource (for example, a certain number of REs (for example, a single RE)) in each layer.
More specifically, the coding rate r CW#0 of CW#0 indicates the number of bits in CW#0 that can be transmitted using a single RE, and the coding rate r CW#1 of CW#1 indicates the number of bits in CW#1 that can be transmitted using a single RE. Assuming that the number of layers in which CW#0 is allocated is indicated by L CW#0 and the number of layers in which CW#1 is allocated is indicated by L CW#1 , and the number of bits W RE that can be transmitted using a single RE in all the layers ((L CW#0 +L CW#1 ) layers) is obtained from equation 8:
[8]
W RE =r CW#0 ×L CW#0 +r CW#1 ×L CW#1 (Equation 8)
To put it more specifically, this equation indicates that each layer can transmit (W RE /(L CW#0 +L CW#1 )) bits of data signal using a single RE on average. Namely, (W RE /(L CW#0 +L CW#1 )) may be used as the average of coding rates (i.e., the number of bits that can be transmitted using a single RE) of a CW allocated to each layer. This achieves reception quality necessary to maintain the reception quality required by each CW to which the control information is allocated at a minimum amount of resource required after combination of the two CWs transmitted in a plurality of layers.
Resource amount determining section 204 , in accordance with equation 9 below, determines the amount of the resource of control information Q CW#0+CW#1 in each layer based on the inverse of the average of the coding rates of the CWs assigned to each layer ((r CW#0 ×L CW#0 +r CW#1 ×L CW#1 )/(L CW#0 +L CW#1 )).
[
9
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
r
CW
#0
×
L
CW
#0
+
r
CW
#1
×
L
CW
#1
·
β
offset
PUSCH
/
L
⌉
(
Equation
9
)
Resource amount determining section 204 , as shown in equation 9 and as in equation 1, determines the amount of the resource of control information in each layer by multiplying the inverse of the average of the coding rates of the CWs assigned to each layer ((L CW#0 +L CW#1 )/(r CW#0 ×L CW#0 +r CW#1 ×L CW#1 )) by the amount of offset β offset PUSCH and then dividing the result by the total number of layers L.
The average of the coding rates of the CWs assigned to each layer ((r CW#0 ×L CW#0 +r CW#1 ×L CW#1 ) (L CW#0 +L CW#1 )), as shown in equation 9, can be represented by r CW#0 ×(L CW#0 /(L CW#0 +L CW#1 ))+r CW#1 ×(L CW#1 /(L CW#0 +L CW#1 )). This indicates that the coding rate r CW#0 of CW#0 is weighted by the proportion of the number of layers to which CW#0 is assigned (L CW#0 ) in all the number of layers (L CW#0 +L CW#1 ), and that the coding rate r CW#1 of CW#1 is weighted by the proportion of the number of layers to which CW#1 is assigned (L CW#1 ) in all the number of layers (L CW#0 +L CW#1 ).
In other words, resource amount determining section 204 weights the coding rate of each CW by the proportion of the number of layers to which the CW is assigned in all the layers to which a plurality of CWs are assigned. To be more precise, the greater the proportion of the number of layers to which a CW is assigned in all the layers to which a plurality of CWs are assigned is, the greater the weight given to the coding rate of the CW is. For example, in Determination Method 2 (equation 4), the average of the coding rates of the two CWs is simply calculated, and the number of layers to which each CW is assigned is not taken into account. In contrast, in Determination Method 5 (equation 9), the average of the coding rates of a CW in all the layers containing the CW can be calculated accurately.
As shown above, in accordance with Determination Method 5, resource amount determining section 204 determines the amount of the resource of control information in each layer using the average of the numbers of bits that can be transmitted in the same amount of resource (for example, a single RE) in each layer as the average of the coding rates of the CWs allocated to each layer. In this manner, the amount of the resource in consideration of the two CWs assigned to a plurality of layers can be determined. Thus, the degradation of reception quality of control information can be prevented without wasteful use of resource.
Since the rank-1 transmission is used for control information, the amount of resource is identical for each layer. In contrast, a transmission mode other than the rank-1 transmission may be used for data signals, in which case the amount of the resource varies depending on layers. In such a case, the same amount of resource is assumed for each layer and the average number of transmittable bits is calculated, as shown in Determination Method 5, which allows calculation of an appropriate amount of resource. In other words, Determination Method 5 is applicable to data signals with different transmission bandwidths. Suppose, for example, that, on initial transmission (i.e., in sub-frame 0), CW#0 is responded with ACK and CW#1 is responded with NACK, and on retransmission (i.e., in sub-frame 8), a new packet is assigned for CW#0 and a retransmission packet is assigned for CW#1. In this case, there may be a case where the transmission bandwidth differs between the new packet and the retransmission packet in sub-frame 8. In this case, the amount of the resource of control information is calculated by assigning the information on CW#0 that is transmitted initially in sub-frame 8 as CW#0 information, and the information on CW#1 that was transmitted initially in sub-frame 0 in equation 9 as CW#1 information. This method allows calculations of the amount of the resource, assuming that each layer uses the same amount of resource to transmit control information, and is effective when the same control information in a plurality of layers is transmitted at the same time and at the same frequency, that is, when rank-1 transmission is performed.
Furthermore, Determination Method 5 allows terminal 200 to calculate the correction factor based on the coding rates (reception quality) of the two CWs, thereby eliminating the need for base station 100 to notify terminal 200 of the correction factor, unlike in Determination Method 3. Accordingly, Determination Method 5 can reduce the amount of signaling from base station 100 to terminal 200 , as compared with Determination Method 3.
In Determination Method 5, the denominator of the portion corresponding to the inverse of the coding rates in equation 9 ((L CW#0 +L CW#1 )/(r CW#0 ×L CW#0 +r CW#1 ×L CW#1 )) indicates the total number of bits transmittable using a single RE in all the layers to which CW#0 and CW#1 are assigned. This can prevent assignment of an excess amount of resource to control information since the coding rate of the other CW is taken into account, even if either CW#0 or CW#1 has an extremely lower coding rate (extremely small data size).
Assuming that the same amount of resource is assigned to layers to each of which a CW is assigned, the following equations are obtained: M CW#0SC PUSCH-initial ·N CW#Symb PUSCH-initial =M SC PUSCH-initial (0) ·N Symb PUSCH-initial (0) ·L CW#0 and M CW#1SC PUSCH-initial ·N CW#1Symb PUSCH-initial =M SC PUSCH-initial(1) ·N symb PUSCH-initial(1) ·L CW#1 . The M SC PUSCH-initial (0) ·N symb PUSCH-initial (0) indicates an amount of the resource of data signals on initial transmission for each of layers to which CW#0 is assigned, and the M SC PUSCH-initial (1) ·N symb PUSCH-initial (1) indicates an amount of the resource of data signals on initial transmission for each of layers to which CW#1 is assigned. Equation 9 can be simplified to equation 10 using the abovementioned equations. Since L CW#0 +L CW#1 =L, equation 10 is equivalent to equation 11.
[
10
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
CW
#0
sc
PUSCH
-
initial
·
N
CW
#0
symb
PUSCH
-
initial
×
L
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
CW
#1
sc
PUSCH
-
initial
·
N
CW
#1
symb
PUSCH
-
initial
×
L
CW
#1
·
β
offset
PUSCH
/
L
⌉
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
·
β
offset
PUSCH
/
L
⌉
(
Equation
10
)
[
11
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
·
β
offset
PUSCH
⌉
(
Equation
11
)
Assuming that the same amount of resource is assigned to each of layers to which a CW is assigned (W layer =M SC PUSCH-initial ·N Symb PUSCH-initial ), equation 9 can be simplified to equation 12.
[
12
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
CW
#0
sc
PUSCH
-
initial
·
N
CW
#0
symb
PUSCH
-
initial
×
L
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
CW
#1
sc
PUSCH
-
initial
·
N
CW
#1
symb
PUSCH
-
initial
×
L
CW
#1
·
β
offset
PUSCH
/
L
⌉
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
L
CW
#0
×
W
layer
×
L
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
L
CW
#1
×
W
layer
×
L
CW
#1
·
β
offset
PUSCH
/
L
⌉
=
⌈
(
O
+
P
)
·
L
CW
#0
+
L
CW
#1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
W
layer
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
W
layer
·
β
offset
PUSCH
/
L
⌉
=
⌈
(
O
+
P
)
·
(
L
CW
#0
+
L
CW
#1
)
×
W
layer
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
·
β
offset
PUSCH
/
L
⌉
(
Equation
12
)
((L CW#0 +L CW#1 )×W layer ) in equation 12 is equivalent to equation 13 below:
[13]
M CW#0 sc PUSCH-initial ·N CW#0 symb PUSCH-initial +M CW#1 sc PUSCH-initial ·N CW#1 symb PUSCH-initial (Equation 13)
Since W layer =M SC PUSCH-initial ·N symb PUSCH-initial and L CW#0 +L CW#1 =L, equation 10 can be simplified to equation 14 below:
[
14
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
M
SC
PUSCH
-
initial
·
N
symb
PUSCH
-
initial
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
·
β
offset
PUSCH
⌉
(
Equation
14
)
Determination Methods 1 to 5 for determining the amount of the resource of control information have been described.
ACK/NACK and CQI receiving section 111 of base station 100 determines the amount of the resource of control information (ACK/NACK signals or CQIs) in a reception signal using a method similar to Determination Methods 1 to 5 used in resource amount determining section 204 . Based on the determined amount of the resource, ACK/NACK and CQI receiving section 111 extracts an ACK/NACK or CQI to downlink data (PDSCH signals) sent by each terminal from a channel (for example, PUSCH) to which uplink data signals have been assigned.
As shown above, this embodiment can prevent the degradation in reception quality of control information even in the case of adopting the SU-MIMO transmission method.
Embodiment 2
In Embodiment 1, the amount of the resource of control information is determined based on the lower coding rate of the coding rates of the two CWs (code words) or the average of the inverses of the coding rates of the two CWs. Meanwhile, in Embodiment 2, besides the processing in Embodiment 1, the amount of the resource of control information is determined in consideration of a difference in interference between layers for data signals and for control information.
Since the basic configurations of the base station and the terminal in accordance with Embodiment 2 are the same as those in Embodiment 1, FIGS. 4 and 5 are used to describe Embodiment 2.
Besides the processing similar to that of Embodiment 1, setting section 101 ( FIG. 4 ) in base station 100 in accordance with Embodiment 2 sets a correction factor (α offset (L)).
Besides the processing similar to that of Embodiment 1, ACK/NACK and CQI receiving section 111 determines the amount of the resource using the correction factor (α offset (L)) received from setting section 101
Meanwhile, resource amount determining section 204 in terminal 200 according to Embodiment 2 ( FIG. 5 ) uses a correction factor (α offset (L)) notified from base station 100 to determine the amount of the resource.
(Operations of Base Station 100 and Terminal 200 )
The operations of base station 100 and terminal 200 having the above-mentioned configurations will be described below:
<Determination Method 6>
If the number of layers or the number of ranks for control information equals the number of layers or the number of ranks for data signals, the same inter-layer interference occurs between data signals and control information. For example, if spatial multiplexing is performed with CW#0 to which control information is allocated and which is assigned to layer #0 and CW#1 containing data signals assigned to layer #1, a rank-2 transmission is performed for data signals and for control information, causing inter-layer interference of the same level.
Alternatively, if the number of ranks differs between control information and data signals, different inter-layer interference occurs between data signals and control information. If the same control information is allocated in CW#0 and CW#1 and transmitted in layer #0 and layer #1, that is, if a rank-1 transmission is performed, less inter-layer interference occurs, as compared with when different signals are allocated in CW#0 and CW#1 and transmitted in layer #0 and layer #1.
In this respect, resource amount determining section 204 increases or decreases the amount of the resource calculated with an above equation (for example, equation 1), depending on the number of ranks or the number of layers for data signals and for control information.
More specifically, resource amount determining section 204 , as shown in equation 15 below, calculates the amount of the resource Q CW#0+CW#1 by determining the amount of the resource of control information in each layer based on the coding rate of one of CWs (CW#0 or CW#1) or the coding rates of both CWs using the above equation 1, multiplying the determined amount of the resource by a correction factor α offset (L) which depends on the number of ranks or the number of layers, and then dividing the result of multiplication by the total number of layers L.
[
15
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
×
1
r
CW
#0
×
β
offset
PUSCH
/
L
×
α
offset
(
L
)
⌉
(
Equation
15
)
In equation 15, α offset (L) represents a correction factor that depends on the number of layers or the number of ranks for data signals and for control information.
For example, if the number of ranks or the number of layers for data signals is larger than that of control information, the correction factor α offset (L), as shown in FIG. 7 , implicitly decrease as a difference in the number of ranks or the number of layers between data signals and control information increases. As the difference in the number of ranks or the number of layers between data signals and control information decreases, the correction factor is approximated to 1.0.
Alternatively, if the number of ranks or the number of layers for data signals is smaller than that for control information, the correction factor α offset (L), as shown in FIG. 8 , implicitly increases as a difference in the number of ranks or the number of layers between data signals and control information increases.
The inter-layer interference is dependent on channel variations (or channel matrix): thus, inter-layer interference varies even if the number of ranks or the number of layers is identical, which means an appropriate correction is difficult using one set value. To cope with this problem, a plurality of correction factors α offset shared between base station 100 and terminal 200 are provided in each layer to allow base station 100 to select one from the correction factors and notify terminal 200 via upper layers or PDCCH. Terminal 200 receives the correction factor α offset from base station 100 and uses it to calculate the amount of the resource, as in Determination Method 6. Base station 100 may report the amount of offset β offset PUSCH for each layer (or each rank).
the amount of the resource can be set in consideration of a difference in inter-layer interference between data signals and control information. Thus, the degradation of reception quality of control information can be prevented, while wasteful use of resource can be reduced.
Since inter-layer interference is dependent on channel variations (or channel matrix), upper layers cannot change channels frequently. To cope with frequently-occurring channel variations, the presence or absence of a correction factor may be reported using one bit in a physical downlink control channel (PDCCH) message having a shorter notification interval than upper layers. The PDCCH message is conveyed in each sub-frame, thereby facilitating flexible switching. Furthermore, use of one bit in the PDCCH to direct switching between use or non-use of the correction factor leads to a reduction in the amount of signaling.
The above-mentioned correction factor has a variable set value, depending on the control information (ACK/NACK signals and CQIs and/or the like), but a common notification (notification using a common set value) may be used for the control information (ACK/NACK signals and CQIs and/or the like). For example, if a set value 1 is conveyed to a terminal, the terminal selects a correction factor for ACK/NACK signals that corresponds to the set value 1 and a correction factor for CQIs that corresponds to the set value 1. This allows notification using a single set value for a plurality of parts of control information, thereby reducing the amount of signaling for notification of a correction factor.
this embodiment, the correction factor is increased or decreased, depending on the number of ranks or the number of layers for data signals and for control information, but since the number of layers and the number of ranks are closely related with CWs, the correction factor may be increased or decreased, depending on the number of CWs containing data signals and control information. Furthermore, the correction factor may be changed, depending on whether the number of ranks, the number of layers or the number of CWs for data signals and for control information is equal to or exceeds 1.
Embodiment 3
Embodiment 1 assumes that the number of layers is identical between initial transmission and retransmission. In contrast, in Embodiment 3, the amount of the resource of control information is determined in consideration of a difference in the number of layers between initial transmission and retransmission in the processing shown in Embodiment 1.
Since the basic configurations of the base station and the terminal according to Embodiment 3 is the same as those of Embodiment 1, FIGS. 4 and 5 are used to describe Embodiment 3.
ACK/NACK and CQI receiving section 111 in base station 100 according to Embodiment 3 ( FIG. 4 ) performs processing similar to that of Embodiment 1 and calculates the amount of the resource required to allocate control information based on the number of layers on initial transmission and on retransmission. ACK/NACK and CQI receiving section 111 in Embodiment 3 differs from that in Embodiment 1 in that the equation to calculate the amount of the resource of control information is expanded.
Meanwhile, resource amount determining section 204 in terminal 200 according to Embodiment 3 ( FIG. 5 ) performs processing similar to that of Embodiment 1 and calculates the amount of the resource required to allocate control information based on the number of layers on initial transmission and retransmission. Resource amount determining section 204 in Embodiment 3 differs from that in Embodiment 1 in that the equation to calculate the amount of the resource of control information is expanded.
(Operations of Base Station 100 and Terminal 200 )
The operations of base station 100 and terminal 200 having the above-mentioned configurations will be described.
<Determination Method 7>
Determination Methods 1 to 6 assume that the number of layers is identical between initial transmission and retransmission. On initial transmission, the reception quality that is equal to or greater than a certain level (required reception quality) can be achieved for control information by setting the amount of the resource of control information using, for example, equation 9 (Determination Method 5).
Since Determination Methods 1 to 6 (for example, equation 9) assume that the amount of the resource of control information is identical for each layer between initial transmission and retransmission, the total amount of the resource of control information in all the layers also decreases due to a reduction in the number of layers when the number of layers is changed on retransmission (for example, decreases). This results in the degradation of reception quality of control information on retransmission, as compared with that on initial transmission (for example, see FIG. 9 ). For example, as shown in FIG. 9 , if allocation notification information (UL grant) is used to change the number of layers from four (on initial transmission) to two (on retransmission), the amount of resource of data signals decreases and thus the total amount of the resource of control information (for example, ACK/NACK signals) also decreases in all the layers.
resource amount determining section 204 re-sets the amount of the resource of control information on retransmission based on the number of layers in which each CW is allocated on retransmission. More specifically, on retransmission, resource amount determining section 204 does not use the amount of the resource per layer which was calculated on initial transmission, and instead, assigns the number of layers in which each CW is allocated on retransmission (i.e., current number) in equation 9 to re-calculate the amount of the resource per layer on retransmission (i.e., current amount). For the information other than the number of layers (i.e., M CW#0SC PUSCH-initial , M CW#1 SC PUSCH-initial N CW#0Symb PUSCH-initial , N CW#1Symb PUSCH-initial , ΣK r CW#0 and ΣK r CW# ), the numerical values used on initial transmission that have been set to meet a certain error rate requirement (for example, 10%) are used. More specifically, taking L CW#0 +L CW#1 =L into account, equation 9 on retransmission (i.e., currently) can be transformed into equation 16.
[
16
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
1
r
CW
#0
×
L
CW
#0
current
+
r
CW
#1
×
L
CW
#1
current
·
β
offset
PUSCH
⌉
(
Equation
16
)
L CW#0 current and L CW#1 current indicate the number of layers to which CW#0 and CW#1 are assigned on retransmission (i.e., currently), respectively, and L CW#0 initial and L CW#1 initial indicate the number of layers to which CW#0 and CW#1 are assigned on initial transmission, respectively. Since Determination Methods 1 to 6 assume that the number of layers is identical between initial transmission and retransmission, the number of layers is not considered on initial transmission and retransmission. Hence, the number of layers used in Determination Methods 1 to 6 represents the information on initial transmission, just like the number of bits in each CW and/or the amount of the resource in each CW.
Equation 16 is derived by multiplying each term in the denominator of equation 9 by the ratio of the number of layers on retransmission to that on initial transmission (i.e., L CW#0 current /L CW#0 initial , L CW#1 current /L CW#1 initial ). Equation 17 is derived from equations 16 and 11.
[
17
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
1
r
CW
#0
×
L
CW
#0
initial
×
L
CW
#0
current
L
CW
#0
initial
+
r
CW
#1
×
L
CW
#1
initial
×
L
CW
#1
current
L
CW
#1
initial
×
β
offset
PUSCH
⌉
=
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
×
L
CW
#0
current
L
CW
#0
initial
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
×
L
CW
#1
current
L
CW
#1
initial
·
β
offset
PUSCH
⌉
(
Equation
17
)
Equation 19 indicates that if the number of layers for transmitting data signals decreases, the amount of the resource of control information per layer increases. This means that the total amount of resource of layers containing control information is almost identical (i.e., the number of layers containing control information×the amount of the resource of control information per layer) is almost identical) between initial transmission and retransmission, thereby achieving the reception quality that is equal to or exceeds a certain level (required reception quality) for control information even on retransmission (see FIG. 10 .).
This allows the amount of the resource of control information to be set in consideration of the number of layers on retransmission (currently) even if the number of layers transmitting data signals differs between initial transmission and retransmission. Thus, the degradation of reception quality of control information can be prevented without wasteful use of resource.
If the ratio of the number of layers on retransmission to that on initial transmission (i.e., the number of layers on retransmission/the number of layers on initial transmission) is 1/A fold (A: integer) for both of CW#0 and CW#1, equation 18 below may be substituted for equation 17.
[
18
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
·
β
offset
PUSCH
·
L
current
L
initial
⌉
(
Equation
18
)
L initial and L current indicate the total number of layers on initial transmission and on retransmission, respectively. Unless the above-mentioned condition (i.e., the number of layers on retransmission/the number of layers on initial transmission)=1/A) is met, the amount of the resource of control information may be excessive or insufficient, which results in wasteful use of the resource or low quality. If the probability of not meeting the above condition is low, or if the system is designed so as to avoid such occurrence, resource amount determining section 204 may use equation 18 to calculate the amount of the resource of control information.
The case in which the total amount of resource (for example, the number of layers) on retransmission is reduced from that on initial transmission has been described above. The total amount of resource (for example, the number of layers) on retransmission may increase from that on initial transmission. In that case, resource amount determining section 204 may use equation 16, 17 or 18 to prevent the assignment of an excess amount of resource to control information.
The number of layers may be replaced with the number of antenna ports. For example, the number of layers on initial transmission in the above description (i.e., four layers in FIG. 10 ) is replaced with the number of antenna ports (four ports in FIG. 10 ), the number of layers on retransmission (currently) (two layers in FIG. 10 ) is replaced with the number of antenna ports on retransmission (currently) (two ports in FIG. 10 ), and the total number of layers is replaced with the total number of antenna ports. In other words, resource amount determining section 204 replaces the number of layers in equation 16, 17 or 18 with the number of antenna ports to calculate the amount of the resource of control information.
Note that if the number of layers is defined as the number of antenna ports through which different signaling sequences are transmitted, the number of layers is not always identical to the number of antenna ports. For example, when a rank-1 transmission is performed through four antenna ports, the number of layers is one since the same signaling sequence is transmitted though the four antenna ports. In this case, if a 4-layer transmission is performed using four antenna ports on initial transmission, while a 1-layer transmission (rank-1 transmission) is performed using four antenna ports on retransmission, the amount of the resource of control information need not be corrected. In contrast, if a 4-layer transmission is performed using four antenna ports on initial transmission, while a 1-layer transmission (using one layer) is performed using one antenna port on retransmission, the amount of the resource of control information needs to be corrected.
If the number of antenna ports used for retransmission decreases, transmission power per antenna port is increased to compensate for the decrease, thereby avoiding the correction of the amount of the resource of control information. For example, if the number of antenna ports is reduced from four to two, the transmission power per antenna port may be increased by 3 dB (i.e., doubled), and if the number of antenna ports is reduced from four to one, the transmission power per antenna port may be increased by 6 dB (i.e., quadruplicated).
If a precoding vector (or matrix) in which the number of antenna ports used on retransmission is identical to that on initial transmission is used, equation 11 or 14, for example, may be used. If a precoding vector (or matrix) in which the number of antenna ports used on retransmission is different from that on initial transmission is used, for example, the number of layers in equation 16, 17 or 18 may be used with the number of layers replaced with the number of antenna ports.
Equations 16 and 17 may be applicable to a case in which one of CWs is responded with ACK and the other CW is responded with NACK, resulting in a decrease in the number of CWs. More specifically, if CW#0 is responded with ACK, while CW#1 is responded with NACK on initial transmission, and only CW#1 is thus retransmitted, L CW#0 current =0 is assigned in equation 16 or 17 and the amount of the resource of control information is calculated from equation 19. Equation 19 indicates a case in which only CW1 is responded with NACK, but if only CW0 is responded with NACK, the CW1 information in equation 19 may be replaced with CW0 information.
[
19
]
Q
CW
#0
+
CW
#1
==
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
×
L
CW
#1
current
L
CW
#1
initial
·
β
offset
PUSCH
⌉
(
Equation
19
)
If signals are transmitted in the two CWs, equation 11 or 14 may be used. If signals are retransmitted in a single CW, equation 19 may be used as exception processing. For example, if 4-antenna-port transmission is performed using the two CWs on initial transmission and if 2-antenna-port transmission is performed using a single CW on retransmission, equation 19 is used on retransmission. In the fallback mode, which is used when reception quality undergoes extreme degradation, for example, 1-antenna-port transmission may be performed using a single CW on retransmission, in which case equation 19 may be used as exception processing. Equation 19 may incorporate a correction value as shown in equation 20.
[
20
]
Q
CW
#0
+
CW
#1
==
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
×
W
×
β
offset
PUSCH
⌉
(
Equation
20
)
W in equation 20 indicates a correction factor. Correction value W may be determined based on the number of layers (or number of antenna ports) for CW0 or CW1 on initial transmission and on retransmission. For example, the correction value W in equation 20 is the ratio of number of antenna ports to which CW0 or CW1 is assigned on retransmission to the number of antenna ports to which CW0 or CW1 is assigned on initial transmission. The correction value W may be included in the amount of offset β offset PUSCH . For example, the amount of offsetβ offset PUSCH is determined based on the number of layers (or number of antenna ports) for CW0 or CW1 on initial transmission and on retransmission.
The case in which the calculation of the amount of resource on retransmission using CW information used in initial transmission has been described. A reason for calculating the amount of the resource on retransmission using CW information used in initial transmission is that the data signal error rate on retransmission may not be set to a constant value such as 10%. More specifically, on initial transmission, a base station allocates resource to each terminal such that the data signal error rate is 10%, while on retransmission the base station is likely to assign a smaller amount of resource to data signals than on initial transmission since it is sufficient as long as an improvement in the initial data signal error rate on retransmission is made. In other words, in the equation calculating the amount of the resource of control information, a reduction in the amount of the resource of data signals (i.e., M SC PUSCH-retransmission ·N symb PUSCH-retransmission ) on retransmission results in a reduction in the amount of the resource of control information, which leads to the degradation of reception quality of control information. To cope with this problem, the information on initial transmission is used to determine the amount of resource, thereby keeping the reception quality that is equal to or exceeds a certain level (i.e., required reception quality) for control information. Note that ΣK r , ΣK r CW#0 and ΣK r CW#1 are identical between initial transmission and retransmission.
Even if a data error rate is set to 10% (0.1) on initial transmission, the data signal error rate may exceed 10% due to delay on retransmission (i.e., the error rate may further increase.) To address this problem, preferably, the correction value (K) is multiplied when the amount of the resource on retransmission is determined. For example, as shown in equation 21, the ratio of the number of layers for each CW on initial transmission (L CW#0 initial , L CW#1 initial ) to the number of layers for each CW on retransmission (L CW#0 current , L CW#1 current ) may be multiplied by a correction value specific to the term generated for each CW (K CW#0 , K CW#1 ). Alternatively, as shown in equation 22, the ratio of the number of layers (L initial ) on initial transmission to the number of layers (L current ) on retransmission may be multiplied by the correction value (K). Correction values are not limited to the above-mentioned examples, and one or more time delays may be multiplied by a correction value.
[
21
]
Q
CW
#0
+
CW
#1
==
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
×
L
CW
#0
current
L
CW
#0
initial
×
K
CW
#0
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
×
L
CW
#1
current
L
CW
#1
initial
×
K
CW
#1
·
β
offset
PUSCH
⌉
(
Equation
21
)
[
22
]
Q
CW
#0
+
CW
#1
=
⌈
(
O
+
P
)
·
1
∑
r
=
0
C
CW
#0
-
1
K
r
CW
#0
M
sc
PUSCH
-
initial
(
0
)
·
N
symb
PUSCH
-
initial
(
0
)
+
∑
r
=
0
C
CW
#1
-
1
K
r
CW
#1
M
sc
PUSCH
-
initial
(
1
)
·
N
symb
PUSCH
-
initial
(
1
)
·
β
offset
PUSCH
×
L
current
L
initial
×
K
⌉
(
Equation
22
)
Unlike Determination Methods 1 to 7, a restriction that the same number of layers as that on initial transmission should be always used on retransmission may be imposed. For example, changing the number of layers for each CW on retransmission with allocation information (UL grant) or the like may be prohibited. ACK/NACKs may be transmitted in the same number of layers as that on initial transmission even if the number of layers for each CW decreases on retransmission.
The embodiments of the present invention have been described above.
Other Embodiments
(1) The MIMO transmission mode in the above-mentioned embodiments may be transmission mode 3 or 4, as set forth in LTE, that is, a transmission mode that supports transmission of two CWs, and the non-MIMO transmission mode may be any other transmission mode, that is, a transmission mode in which only single CW is transmitted. The description of the above-mentioned embodiments has assumed the MIMO transmission mode using a plurality of CWs and the non-MIMO transmission mode using a single CW. More specifically, as described above, the above description has been made on the assumption that signals are transmitted in a plurality of layers (or a plurality of ranks) in the MIMO transmission mode and that signals are transmitted in a single layer (or single rank) in the non-MIMO transmission mode. The transmission modes, however, should not be limited to these examples; signals may be transmitted through a plurality of antenna ports in the MIMO transmission mode (for example, the SU-MIMO transmission) and signals may be transmitted through a single antenna port in the non-MIMO transmission mode.
The code words in the above-mentioned embodiments may be replaced with transport blocks (TB).
(2) In the above-mentioned embodiments, ACK/NACKs and CQIs are used as examples of control information, but the control information is not limited to the information. Any information (control information) that requires higher reception quality than data signals is applicable. For example, CQIs or ACK/NACKs may be replaced with PMIs (information concerning pre-coding) and/or RI (i.e., information concerning ranks).
(3) The term “layer” in the above-mentioned embodiments refers to a virtual transmission path in the space. For example, in the MIMO transmission, data signals generated in each CW are transmitted in different virtual transmission paths (i.e., different layers) in the space at the same time and at the same frequency. The term “layer” may be referred to as a “stream.”
(4) In the above-mentioned embodiments, a terminal that determines the amount of resource of control information based on a difference in coding rates between the two CWs to which control information is allocated (or coding rate ratio) has been described. A difference in MCS between the two CWs (or an MCS ratio) may be used, instead of a difference in coding rates between the two CWs to which control information is allocated (or coding rate ratio). Alternatively, a combination of a coding rate and a modulation method may be used as a coding rate.
(5) The above-mentioned amount of offset may be referred to as a correction factor, and the correction factor may be referred to as an amount of offset. Any two or three of the correction factors and amounts of offset (α offset (L), β offset PUSCH and γ offset ) used in the above-mentioned embodiments may be combined into one correction factor or offset.
(6) In the above-mentioned embodiments, the description has been given with antennas, but the present invention can be applied to antenna ports as well.
The antenna port refers to a logical antenna composed of one or more physical antennas. Thus, an antenna port does not necessarily refer to one physical antenna, and may refer to an antenna array composed of a plurality of antennas.
For example, in 3 GPP LTE, how many physical antennas are included in the antenna port is not specified, but an antenna port is specified as a minimum unit allowing the base station to transmit a different reference signal.
In addition, the antenna port may be specified as a minimum unit in multiplication of a weight of the precoding vector.
The number of layers may be defined as the number of different data signals transmitted concurrently in the space. Furthermore, the layer may be defined as a signal transmitted through an antenna port associated with data signals or reference signals (or as a communication path thereof in the space). For example, a vector used for weight control (precoding vector) that has been studied for uplink demodulation pilot signals in LTE-A has one-to-one relationship with a layer.
(7) The above-mentioned embodiments have been described by taking an example of the present invention being implemented by hardware, but the present invention may be implemented by software in cooperation with hardware.
Functional blocks used to describe the above-mentioned embodiments are typically achieved by LSIs, which are integrated circuits. The integrated circuits may be implemented individually into separate chips, or all or part of the integrated circuit may be implemented into one chip. Although such integrated circuits are referred to as LSIs herein, they may be called ICs, system LSIs, super LSIs or ultra LSIs, depending on the degree of integration.
The methods for manufacturing integrated circuits are not limited to LSIs, and dedicated circuits or general-purpose processors may be used to implement them. After LSI production, field programmable gate arrays (FPGAs) or reconfigurable processors that allow connection or setting of circuit cells within LSIs may be used.
If advancement in semiconductor technology or other technology derived therefrom leads to emergence of integrated circuit manufacturing technology that takes the place of LSI, obviously, such technology may be used to integrate functional blocks. Biotechnology may also be applicable.
The entire disclosure of the specifications, drawings and abstracts in Japanese Patent Application No 2010-140751 filed on Jun. 21, 2010 and Japanese Patent Application No 2010-221392 filed on Sep. 30, 2010 are incorporated herein by reference.
INDUSTRIAL APPLICABILITY
The present invention is useful in mobile communication systems and/or the like.
REFERENCE SIGNS LIST
100 base station
200 terminal
101 setting section
102 , 103 coding and modulating section
104 , 205 transmission signal generating section
105 , 206 transmitting section
106 , 201 antenna
107 , 202 reception section
108 , 208 radio processing section
109 , 203 reception processing section
110 data reception section
111 ACK/NACK and CQI receiving section
204 resource amount determining section
207 transmission processing section | This invention is directed to a terminal apparatus capable of preventing the degradation of reception quality of control information even in a case of employing SU-MIMO transmission system. A terminal ( 200 ), which uses a plurality of different layers to transmit two code words in which control information is placed, comprises: a resource amount determining unit ( 204 ) that determines, based on a lower one of the encoding rates of the two code words or based on the average value of the reciprocals of the encoding rates of the two code words, resource amounts of control information in the respective ones of the plurality of layers; and a transport signal forming unit ( 205 ) that places, in the two code words, the control information modulated by use of the resource amounts, thereby forming a transport signal. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the U.S. National Phase application of PCT International Application No. PCT/FR2011/051652, filed Jul. 12, 2011, and claims priority to French Patent Application No. 1055718, filed Jul. 13, 2010, the disclosures of which are incorporated by reference in their entirety for all purposes.
FIELD OF THE INVENTION
The present invention relates to nitrogenous associative molecules comprising at least one unit rendering them capable of associating with one another or with a filler, via noncovalent bonds, and comprising a function capable of reacting with a polymer containing unsaturations so as to form a covalent bond with said polymer.
The modified polymers comprising associative groups along the polymeric chain are polymers comprising at least one unit rendering them capable of associating with one another or with a filler via noncovalent bonds. An advantage of these polymers is that these physical bonds are reversible under the influence of external factors, such as temperature or stress time, for example. Thus, the mechanical properties of these modified polymers can be modulated according to the parameters of the environment in which they are used.
Such polymers are, for example, described in the document published under number WO 2010/031956.
SUMMARY OF THE INVENTION
This document describes elastomers comprising flexible polymer chains associated with one another, firstly, via permanent crosslinking bridges having covalent bonds and, secondly, via crosslinking bridges having noncovalent bonds. The molecules grafted on to the elastomers comprise associative groups based on a nitrogenous heterocycle enabling the establishment of physical bonds. Mentioned among the associative groups envisioned in this document are imidazolidinyl, triazolyl, triazinyl, bis-ureyl and ureidopyrimidyl groups.
In order to modify the elastomers, said elastomer can be reacted with a molecule comprising, firstly, the associative group and, secondly, a reactive group forming a covalent bond with a reactive function borne by the elastomer. This therefore involves prior functionalization of the elastomer.
It is found, in addition, that the elastomers thus modified comprise a certain proportion of functions which have not reacted and which influence the final properties of the material.
This is the reason why research has been carried out on other processes for modifying polymers in order to introduce associative groups along the chain.
The objective of the present invention is therefore to propose an alternative for modification of polymers applicable also to polymers which do not comprise reactive functions.
This objective is achieved in that the inventors have just discovered novel molecules comprising both at least one associative group and at least one reactive group, which make it possible to modify a polymer, comprising at least one double bond, without it being necessary for the polymer in question to comprise reactive functions.
DETAILED DESCRIPTION
A subject of the invention is a compound comprising at least one group Q, and at least one group A linked together by at least and preferably one “spacer” group Sp, in which:
Q comprises an azodicarbonyl unit, A comprises an associative group comprising at least one nitrogen atom, Sp is an atom or a group of atoms forming a link between Q and A.
A polymer grafted with a compound as defined above is mixed with fillers; said compound establishes only labile bonds with the fillers, which makes it possible to provide good polymer-filler interaction, beneficial for the final properties of the polymer, but without the drawbacks that too strong a polymer-filler interaction could cause.
The term “associative group” is intended to mean groups capable of associating with one another via hydrogen, ionic and/or hydrophobic bonds. According to one preferred embodiment of the invention, they are groups capable of associating via hydrogen bonds.
When the associative groups are capable of associating via hydrogen bonds, each associative group comprises at least one donor “site” and one acceptor site with respect to the hydrogen bond such that two identical associative groups are self-complementary and can associate together by forming at least two hydrogen bonds.
The compounds according to the invention comprising a group Q, a “spacer” group and an associative group can, for example, be represented by formula (Ia) below:
A-Sp-Q (Ia).
The compounds according to the invention comprising a group Q, a “spacer” group and two associative groups can, for example, be represented by formula (Ib) below:
Similarly, the compounds according to the invention comprising two groups Q, a “spacer” group and an associative group can, for example, be represented by formula (Ic) below:
According to the same principle, the compounds according to the invention comprising two groups Q, a “spacer” group and two associative groups can, for example, be represented by formula (Id) below:
Preferably, the associative group is chosen from an imidazolidinyl, ureyl, bis-ureyl, ureidopyrimidyl and triazolyl group.
Preferably, the group A corresponds to one of the formulae (II) to (VI) below:
wherein:
R denotes a hydrocarbon-based group which can optionally contain heteroatoms, X denotes an oxygen or sulfur atom, preferably an oxygen atom.
Preferably, the group A comprises a dinitrogenous or trinitrogenous heterocycle, generally containing 5 or 6 atoms, which is preferably dinitrogenous, and which comprises at least one carbonyl function. In at least one embodiment, the group A comprises an imidazolidinyl group of formula (II).
The group Q comprises an azodicarbonyl group preferably corresponding to the formula:
W—CO—N═N—CO—
in which,
W represents
a group of formula:
R′—Z—,
in which:
—Z represents an oxygen or sulfur atom or an —NH or —NR′ group, —R′ represents a C 1 -C 20 alkyl group, preferably a C 1 -C 6 alkyl, such as C 1 -C 4 alkyl, including example methyl or ethyl,
or
a group of formula:
-Sp′-A′
in which:
Sp′, which may be identical to or different than Sp, is a divalent spacer group linking the azodicarbonyl functional group to another associative group A′, A′, which may be identical to or different than A, is an associative group comprising at least one nitrogen atom,
A, Sp and Sp′ possibly comprising one or more heteroatoms.
Preferably, the compounds which are subjects of the invention are represented by formula (VII)
W—CO—N═N—CO-Sp-A (VII)
in which
A is an associative group comprising at least one nitrogen atom,
Sp is a divalent spacer group linking the azodicarbonyl functional group to the associative group A,
W is as defined previously, and
A, Sp and Sp′ can comprise one or more heteroatoms.
Compounds which are subjects of the invention are represented by formula (VIII) or (IX):
R′—Z—CO—N═N—CO-Sp-A (VIII)
or
A′-Sp′-CO—N═N—CO-Sp-A (IX)
in which:
R′, Z, Sp, A, Sp′ and A′ are as defined previously and A, Sp and Sp′ can comprise one or more heteroatoms.
The “spacer” group Sp makes it possible to link at least one group Q and/or at least one associative group, and thus may be of any type known per se. However, the “spacer” group must interfere little, or not at all, with the groups Q and associative groups of the compound according to the invention.
Said “spacer” group is therefore considered to be a group that is inert with respect to the group Q, which preferably does not have any alkenyl functions capable of reacting with this group.
The “spacer” group is preferably a linear, branched or cyclic hydrocarbon-based chain, and can contain one or more aromatic radicals and/or one or more heteroatoms. Said chain can optionally be substituted, provided that the substituents are inert with respect to the groups Q.
According to one preferred embodiment, the “spacer” group is a linear or branched C 1 -C 24 , preferably C 1 -C 10 , alkyl chain, such as a linear C 1 -C 6 alkyl chain, optionally comprising one or more heteroatoms chosen from nitrogen, sulfur, silicon or oxygen atoms.
In at least one embodiment, the “spacer” group Sp or Sp′ is chosen from —(CH 2 ) y —, —NH— (CH 2 ) y — and —O—(CH 2 ) y —, y being an integer from 1 to 6.
Preferably, the compound which is the subject of the invention is chosen from the compounds of formula (X) or (XI) below:
in which:
Y represents a divalent group chosen from a methylene group, an oxygen atom, a sulfur atom and an —NH— group, and
R represents a C 1 -C 6 alkoxyl group, preferably a C 1 -C 4 alkoxyl group, such as methoxyl or ethoxyl.
In at least one embodiment, the compound according to the invention can be chosen from the compounds of formulae (XII) to (XV) below:
The compounds which are subjects of the invention can be prepared in three steps according to the following general scheme:
or else by direct reaction with a dialkyl azodicarboxylate or a dialkyl hydrazodicarboxylate according to the following reaction scheme:
The following examples are provided by way of illustration, it being possible to envision other synthesis pathways or improvements to those described below.
Example 1
Preparation of (E)-ethyl 2-(2-(2-oxoimidazolidin-1-yl)ethylcarbamoyl)diazenecarboxylate
a) Preparation of N-(2-(2-oxoimidazolidin-1-yl)ethyl)-1H-imidazole-1-carboxamide
The N-(2-(2-oxoimidazolidin-1-yl)ethyl)-1H-imidazole-1-carboxamide was prepared according to the following procedure:
Carbonyldiimidazole (64.2 g, 0.4 mol) was added, in one step, to a solution of 1-(2-aminoethyl)imidazolidin-2-one (46.5 g, 0.36 mol) in anhydrous acetonitrile (750 ml). The reaction medium was then stirred for 3 to 5 hours at ambient temperature. The precipitate obtained was filtered off and washed on the filter with dry acetonitrile (3 times 40 ml) and petroleum ether (twice 50 ml, 40/60° C. fraction) and, finally, dried for 10-15 hours at ambient temperature.
A white solid (74.5 g, yield 93%) with a melting point of 154° C. was obtained.
The molar purity was 88 mol % ( 1 H NMR).
1 H, 13 C, 15 N NMR characterization
δ 1 H (ppm) + δ 13 C Atom mult. (ppm) δ 15 N (ppm) 1 — 162.4 — 2 6.26 (s) — −302.7 ( 1 J 1H−15N = 90 Hz) 3 3.15 (t) 37.5 — 4 3.34 (t) 44.7 — 5 — — −299.2 6 3.17 (t) 42.5 — 7 3.28 (t) 38.4 — 8 8.53 — −286.3 ( 1 J 1H−15N = 90 Hz) 9 — 148.8 — 10 — — −185.1 11 8.14 (s) 135.9 — 12 — — −112.6 13 6.95 (s) 139.5 — 14 7.57 (s) 116.6 —
Solvent used: DMSO—calibration on the signal of DMSO at 2.44 ppm in 1 H, 39.5 ppm in 13 C and sr=19238.46 in 15 N
b) Preparation of ethyl 2-(2-(2-oxoimidazolidin-1-yl)ethylcarbamoyl)hydrazinecarboxylate
Ethyl hydrazinecarboxylate (38.0 g, 0.36 mol) was added, in one step, to N-(2-(2-oxoimidazolidin-1-yl)ethyl)-1H-imidazole-1-carboxamide (74.0 g, 0.33 mol, purity 88 mol % by NMR) in anhydrous acetonitrile (750 ml). The reaction medium was stirred for 3 hours at 70-75° C. and then for 2-3 hours at ambient temperature.
The precipitate was filtered off and washed with acetonitrile (twice 50 ml) and petroleum ether (twice 50 ml, 40/60° C. fraction) and, finally, dried for 10-15 hours at ambient temperature.
A white solid (79.6 g, yield 93%) with a melting point of 179° C. was obtained.
The molar purity was greater than 99% ( 1 H NMR).
1 H, 13 C, 15 N NMR characterization
δ 13 C
Atom
δ 1 H (ppm) + mult.
(ppm)
δ 15 N (ppm)
1
—
162.4
—
2
6.20
—
−303.1
( 1 J 1H−15N = 90 Hz)
3
3.13
(t)
37.6
—
4
3.28
(t)
45.0
—
5
—
—
−298.2
6
2.99
(t)
43.4
—
7
3.04
(t)
37.9
—
8
6.33/7.69/8.30/8.68*
—
−301.3*
9
—
158.3
—
10
6.33/7.69/8.30/8.68*
—
−301.3*
11
6.33/7.69/8.30/8.68*
—
−301.3*
12
—
156.9
—
13
3.96
(q)
60.4
—
14
1.11
(t)
14.6
—
Since protons 8, 10 and 11 are NH groups, their 1 H chemical shift cannot be assigned precisely. The 13 C chemical shift corresponds to group 8.
Solvent used: DMSO—calibration on the signal of DMSO at 2.44 ppm in 1 H, 39.5 ppm in 13 C and sr=19238.46 in 15N
c) Preparation of ethyl 2-(2-(2-oxoimidazolidin-1-yl)ethylcarbamoyl)diazenecarboxylate, compound according to the invention
N-Bromosuccinimide (6.87 g, 0.039 mol) in dichloromethane (100 ml) was added, in a single step, to a mixture of pyridine (3.05 g, 0.039 mol) and hydrazinecarboxylate (10.00 g, 0.039 mol) in dichloromethane (200 ml), cooled to 5-10° C. The reaction medium was stirred for 1 hour at 10° C. and then the organic phase was washed with water (twice 150 ml). The organic phase was then dried for 15 minutes over Na 2 SO 4 , and then the solvents were evaporated off under reduced pressure (T bath 18° C., 40-50 mbar). Diethyl ether (300 ml) was added and the reaction medium was stirred for 30-40 minutes at ambient temperature. The precipitate obtained was filtered off and washed on the filter with diethyl ether (3 times 40 ml) and, finally, dried for 10-15 hours at ambient temperature.
A yellow solid (6.95 g, yield 70%) with a melting point of 122° C. was obtained.
The molar purity was greater than 95% ( 1 H NMR).
A 1 H, 13 C NMR characterization is provided in the following table 1.
TABLE 1
Atom
δ 1 H (ppm) + mult.
δ 13 C (ppm)
1
—
162.20
2
6.27/9.12*
—
3
3.15
(t)
37.46
4
3.32
(t)
44.59
5
3.17
(t)
42.41
6
3.31
(t)
38.44
7
6.227/9.12*
—
8
—
160.42/161.25
9
—
160.42/161.25
10
4.41
(q)
65.24
11
1.28
(t)
13.83
Since protons 2 and 7 are NH groups, their 1 H chemical shift cannot be assigned precisely.
Solvent used: DMSO—calibration on the signal of DNSO at 2.44 ppm in 1 H, 39.5 ppm in 13 C
Example 2
Preparation of N 1 ,N 2 -bis(2-(2-oxoimidazolidin-1-yl)ethyl)diazene-1,2-dicarboxamide in three steps from UDETA
a) Preparation of N 1 ,N 2 -bis(2-(2-oxoimidazolidin-1-yl)ethyl)hydrazine-1,2-dicarboxamide (SI-BIM-02)
Hydrazine hydrate (0.50 g, 0.01 mol) was added, in one step, to N-(2-(2-oxoimidazolidin-1-yl)ethyl)-1H-imidazole-1-carboxamide (4.46 g, 0.02 mol, purity 86 mol % by NMR) in anhydrous acetonitrile (100 ml) [product of example 1]. The reaction medium was stirred for 3 hours at 70-75° C. and then for 1-2 hours at ambient temperature. The precipitate was filtered off and washed with acetonitrile (25 ml) and petroleum ether (50 ml, 40/60° C. fraction) and, finally, dried for 10-15 hours at ambient temperature.
A white solid (3.16 g, 0.009 mol, yield 92%) with a melting point of 232° C. was obtained.
The molar purity was 900 ( 1 H NMR).
A 1 H and 13 C NMR characterization in DMSO is provided in table 2 and in D 2 O is provided in table 3:
TABLE 2
Atom
δ 1 H (ppm) + mult.
δ 13 C (ppm)
1
—
162.3
2
~6.20
—
3
3.14
(t)
37.5
4
3.29
(t)
44.8
5
3.03
(t)
43.2
6
3.03
(t)
37.7
7
~6.31/7.56
—
8
—
158.6
9
~6.31/7.56
—
Solvent used: DMSO—calibration on the signal of DMSO at 2.44 ppm in 1 H, 39.5 ppm in 13 C
TABLE 3
δ 1 H (ppm) +
Atom
mult.
δ 13 C (ppm)
1
—
164.8
2
—
—
3
3.32 (t)
38.0
4
3.47 (t)
45.1
5
3.18 (t)
42.9
6
3.25 (t)
37.3
7
—
—
8
—
160.5
9
—
—
Solvent used: D 2 O—calibration on the signal of water at 4.7 ppm in 1 H, sr=0 in 13 C.
b) Preparation of N 1 ,N 2 -bis(2-(2-oxoimidazolidin-1-yl)ethyl)diazene-1,2-dicarboxamide, compound according to the invention
N-Bromosuccinimide (0.534 g, 0.003 mol) was added, in one step, at ambient temperature, to a mixture of pyridine (0.237 g, 0.003 mol), N 1 ,N 2 -bis(2-(2-oxoimidazolidin-1-yl)ethyl)hydrazine-1,2-dicarboxamide (1.03 g, 0.003 mol) and dichloromethane (50 ml). The reaction medium was stirred for 1 hour at ambient temperature. The precipitate was filtered off and washed on the filter with dichloromethane (10 ml) and dried for 1 hour. The precipitate was treated with water (20 ml) for 15 minutes, filtered and washed again with water (20 ml) and petroleum ether (20 ml) and, finally, dried for 10-15 hours at ambient temperature.
A light yellow solid (0.62 g, 0.002 mol, yield 61%) with a melting point of 208° C. (decomposition) was obtained.
The molar purity was 90% ( 1 H NMR).
A 1 H and 13 C NMR characterization is provided in table 4.
TABLE 4
Atom
δ 1 H (ppm) + mult.
δ 13 C (ppm)
1
—
162.3
2
~6.28/8.88
—
3
3.15
(t)
37.5
4
3.32
(t)
44.7
5
3.15
(t)
42.6
6
3.28
(t)
38.4
7
~6.28/8.88
—
8
—
161.7
Solvent used: DMSO—calibration on the signal of DMSO at 2.44 ppm in 1 H, 39.5 ppm in 13 C
Example 3
Preparation of N 1 ,N 2 -bis(2-(2-oxoimidazolidin-1-yl)ethyl)diazene-1,2-dicarboxamide in one step from UDETA
1-(2-Aminoethyl)imidazolidin-2-one (1.29 g, 0.010 mol) was added, in a single step, at ambient temperature, to a mixture of diisopropyl azo-1,2-dicarboxylate (1.01 g, 0.005 mol) in ethanol (20 ml). The reaction medium was stirred for one hour at ambient temperature. The precipitate was filtered off and washed with ethanol (20 ml), water (50 ml) and petroleum ether (20 ml), then dried for 10-15 hours at ambient temperature. A light yellow solid (1.26 g, 0.004 mol, yield 740) with a melting point of 193° C. (decomp.) was obtained. The purity by 1 H NMR was 87 mol %. | The present invention relates to nitrogenous associative molecules comprising at least one unit rendering them capable of associating with one another or with a filler by noncovalent bonds, and comprising a function capable of reacting with a polymer containing unsaturations so as to form a covalent bond with said polymer. | 2 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention relates generally to the field of controlling photovoltaic solar arrays and more particularly to the control of the temperature of a working fluid circulating through a photovoltaic solar array to enhance control of the power output from the array.
[0003] 2. Description of the Prior Art
[0004] There is growing interest worldwide in reliable and predictable low carbon energy sources such as solar photovoltaic (PV), as the cost of solar power falls relative to fossil generated power. Worldwide PV capacity has recently expanded enough that PV solar arrays in the tens of megawatts in size exist, and larger PV solar arrays are being proposed (i.e. utility scale PV plants). Despite the increased interest and decreased cost, many utilities have been slow to adopt or invest in solar PV arrays for power generation. One complaint frequently cited by utilities is “intermittency of sunlight” or a lack of control over output levels for PV arrays relative to fossil generating technologies. Utilities are used to generating more or less power to meet demand. Simply stated a PV array's power output is primarily dependant on sunlight levels which are hard to predict, let alone control, for any given instant. For such utilities a PV array would provide greater value if they could control its output.
[0005] It is a well established fact that solar PV panels (especially silicon based technologies) suffer from reduced electrical output as their operating temperature increases. It is also common for PV panels to be located in areas with lots of sunlight such that PV panels tend to operate at elevated temperatures. This loss of output can be reversed by lowering the PV panel operating temperature. The prior art teaches numerous methods and arrangements for circulating a working fluid through panels and arrays to reduce the temperature at which they operate, thereby increasing the output from the panels in proportion to the temperature reduction. Frequently this circulating fluid is contained in a loop which may have a reservoir for storing additional working fluid. Many times the heat removed from the PV panel by the working fluid is then used for some additional purpose.
[0006] In U.S. Pat. No. 2,946,945 Regnier et al. teach of a method to improve output from PV solar cells, by circulating a fluid in thermal contact with the PV cells such that the fluid lowers the PV cells operating temperature enabling an increased PV output compared to the output if the fluid were not present. Regnier et al. envisioned using the heat removed from the PV cells by the circulating fluid to heat a battery, improving both the battery's performance and the PV cells' performance. In U.S. Pat. No. 3,976,508 Mlavsky teaches the use of a tubular solar cell device which may be used with a concentrator and cooled by a fluid circulating inside the tubular cells, and using this heated fluid in turn to provide hot water. There are numerous additional examples of prior art PV panels with and without concentration accessories designed to use a fluid in thermal contact with PV solar cells to both improve the performance of the cells (i.e. increase output by cooling the cells) and utilize the resulting heat removed by the working fluid.
[0007] Unfortunately few such “hybrid” systems have been widely adopted despite the well understood benefits. Perhaps this is because the greater complexity, design, material, and operating costs of maintaining both a PV electrical system and a circulating fluid system exceed the limited extra output generated by such a hybrid system.
[0008] It would be advantageous to have a method and apparatus that provides the user greater control of a PV solar array's output, especially if the user were a utility. The flexibility that greater control over the PV array's output might increase the value of PV within the context of managing multiple power generating assets. This would enable much wider use and benefit from our most abundant energy source, the sun.
SUMMARY OF THE INVENTION
[0009] The present invention relates to a method and apparatus for controlling the power output of a PV solar array. Given a fixed amount of sunlight, one can increase (or decrease) the output from a PV array, panel, or cell by decreasing (or increasing) the operating temperature of the PV array, panel, or cell, via a working fluid in thermal contact with the array, panel, or cell. One can control the operating temperature of a working fluid by adding a cold temperature fluid reservoir (and a hot temperature fluid reservoir) and a heat exchanger or controllable mixing valve, to regulate the working fluid temperature, such that a desired PV array operating temperature is achieved.
[0010] If the amount of sunlight reaching a prior art PV array fluctuates, then the output of the PV array varies in proportion. But if one controls the PV array's operating temperature, via the control of the working fluid temperature, one can control the output from the solar PV array to offset the variations in sunlight levels. Thus one can produce a consistent PV output given some variation in light levels by modifying the PV array's operating temperature. Since the operator can select the appropriate working fluid, as well as the hot and cold reservoir temperatures, in principle this setup enables substantial control over the output of the PV array.
[0011] It is an object of the present invention to provide control over the output of a PV array.
[0012] It is another object of the present invention to measure and control the temperature of a working fluid, which is then used to control the temperature of a PV array.
[0013] Finally it is another object of the present invention to increase the range of temperatures over which one may control the temperature of a PV array.
[0014] By adding a cold temperature reservoir and a heat exchanger, or controllable mixing valve, to a system that had a single circulating loop with a fluid at a relatively fixed temperature, one is able to modify (primarily decrease) the operating temperature of the PV array from what it would have otherwise been, boosting the amount of power the PV array can produce at any given light level. And by adding a hot temperature reservoir and a heat exchanger, or controllable mixing valve, one is further able to modify (primarily increase) the operating temperature of the PV array from what it would have otherwise been, reducing the amount of power the PV array can produce at any given light level.
[0015] Intentionally increasing the operating temperature of a PV array (and thus reducing the power output from the array) goes against common sense in the field of solar PV devices, but doing so can be advantageous for two reasons. First this increases the temperature range over which one can control a PV array's output, which grants one control of a greater fraction of the total output. Secondly, it allows an operator, such as a utility, to manage the PV array output in a way that maximizes the value of all its generating assets in combination, rather than just adding a PV array's output (whatever it might be) on top of its existing generating profile.
DESCRIPTION OF THE FIGURES
[0016] Attention is drawn to the following illustrations presented to aid in understanding the present invention.
[0017] FIG. 1 shows a schematic view of a prior art PV array with a circulating fluid loop.
[0018] FIG. 1A shows a plan view of the upper right corner of a prior art PV array with a circulating fluid loop, showing the fluid loop—dashed lines—behind a PV panel.
[0019] FIG. 1B shows a side view of a panel in a prior art PV array with a circulating fluid loop, showing the fluid loop in thermal contact with and under PV material in the panel.
[0020] FIG. 1C shows a plan view of the upper right corner of a prior art PV array built with concentrating optics and with a circulating fluid loop, showing the fluid loop—dashed lines—behind a PV panel.
[0021] FIG. 2 shows a schematic view of an embodiment of the present invention showing a computer for automatic control, a circulating fluid loop with a fluid reservoir, a cold temperature fluid reservoir, a heat transfer device, a PV array, a second heat transfer device, and multiple temperature sensors.
[0022] FIG. 2A shows a cut away view of a heat transfer device used to control the circulating fluid loop temperature, namely a heat exchanger.
[0023] FIG. 3 shows a schematic view of the preferred embodiment of the present invention showing a computer for automatic control, a circulating fluid loop with a fluid reservoir, a cold temperature fluid reservoir, a hot temperature fluid reservoir, a heat transfer device, a PV array, a second heat transfer device, and multiple temperature sensors.
[0024] FIG. 3A shows a cut away view of a heat transfer device used to control the circulating fluid loop temperature, namely an adjustable valve that allows the fluid from different reservoirs to mix directly.
[0025] Several drawings and illustrations have been presented to better explain the construction and functioning of embodiments of the present invention. The scope of the present invention is not limited to what is shown in the figures.
DESCRIPTION OF THE INVENTION
[0026] FIG. 1 and FIG. 1A show a prior art photovoltaic (PV) array with a circulating fluid loop. This is often called a hybrid solar array because it produces both electrical energy and thermal energy (in the form of a fluid heated by the array). A hybrid solar array 20 consists of an array of PV panels 26 , a fluid reservoir 22 , a circulating fluid (not shown) and a circulating fluid conduit 24 in thermal contact with the PV panels 26 . FIG. 1B shows how an individual panel in the array might be constructed. A transparent panel cover 28 is located above a PV material 30 which in turn is located above a thermal contact medium 32 which is in thermal contact with both the PV material 30 and the circulating fluid conduit 24 . FIG. 1C shows one way in which a concentrating optics 34 , in this case reflectors, may be used to increase the amount of sunlight reaching PV material 30 . These figures are intended to simply show the principle elements present in prior art hybrid solar arrays, there are numerous additional ways to construct hybrid solar arrays.
[0027] FIG. 2 shows a schematic view of the preferred embodiment of the present invention, which may be called a dynamic solar array 40 . From left to right the principle elements of the invention are a controller 42 , a first fluid reservoir 44 containing fluid at a first temperature, a second fluid reservoir 46 containing fluid at a second temperature, a first heat transfer device 50 (upper unit), which delivers a fluid at some intermediate temperature to a circulating fluid loop, in thermal contact with PV array 26 . Heat transfer device 50 can be any device for regulating the temperature of two fluid streams, such as a heat exchanger or fluid mixing valve. The circulating fluid loop while not explicitly labeled in FIG. 2 , consists of circulating fluid conduit 24 as was shown in the prior art FIG. 1A , FIG. 1B , & FIG. 1C . FIG. 2 also shows multiple temperature sensors 52 , and a light level sensor 54 that provide feedback/data to controller 42 . Finally FIG. 2 shows a second heat transfer device 50 (lower unit) which may be used to recover heat gained by the fluid in traversing PV array 26 , or otherwise condition the fluid to be returned to either first fluid reservoir 44 or second fluid reservoir 46 .
[0028] FIG. 2A shows an embodiment of heat transfer device 50 , which is essentially a heat exchanger 56 . When controller 42 is able to control both the fluid flow rates, and measure via temperature sensors 52 , (or calculate) the input and output temperature of each fluid, heat exchanger 56 can deliver fluid at a desired temperature between the first fluid temperature and the second fluid temperature.
[0029] FIG. 3 shows a schematic view of an alternate embodiment of the present invention, which may be called a dynamic solar array 40 . From left to right the principle elements of the invention are a controller 42 , a first fluid reservoir 44 containing fluid at a first temperature, a second fluid reservoir 46 containing fluid at a second temperature, a third fluid reservoir 48 containing fluid at a third temperature, a first heat transfer device 50 (upper unit), which delivers a fluid at some intermediate temperature to a circulating fluid loop, in thermal contact with PV array 26 . Heat transfer device 50 can be any device for regulating the temperature of up to three fluid streams, such as a heat exchanger or fluid mixing valve. The circulating fluid loop is (again) not explicitly labeled in FIG. 3 , but consists of circulating fluid conduit 24 as was shown in the prior art FIG. 1A , FIG. 1B , & FIG. 1C . FIG. 3 also shows multiple temperature sensors 52 , and a light level sensor 54 that provide feedback/data to controller 42 . Finally FIG. 3 shows a second heat transfer device 50 (lower unit) which may be used to recover heat gained by the fluid in traversing PV array 26 , or otherwise condition the fluid to be returned to either first fluid reservoir 44 , or second fluid reservoir 46 , or third fluid reservoir 48 .
[0030] FIG. 3A shows an embodiment of heat transfer device 50 , which is essentially a fluid mixing valve 58 . When controller 42 is able to control the three fluid flow rates, and measure via temperature sensor(s) 52 , or calculate, the input and output temperature of each fluid, fluid mixing valve 58 can deliver fluid at a desired temperature between the highest and lowest fluid temperatures.
Operation of the Invention
[0031] The purpose of this invention is to increase the control that a solar array owner or operator has over the output of a solar array. Although one may not always be able to control how much sunlight a PV array receives, one can control the temperature of the PV array which allows one to change the output. The degree of control will be limited by the temperature difference between the two fluid reservoirs (or the range of hottest and coldest fluid temperature if three reservoirs are used) so one will want a wide temperature range. A PV array operator can increase, decrease or hold steady the PV array output.
[0032] Assuming a steady amount of sunlight falls on the preferred embodiment of this invention, and further assuming controller 42 is circulating the fluid through PV array 26 at a temperature (T.sub.m), in the middle of the available temperature range (T.sub.high-T.sub.low), equal amounts of fluid enter heat transfer device 50 (upper unit) from first fluid reservoir 44 and from second fluid reservoir 46 which by assumption is at the lower temperature (T.sub.low).
[0033] If the operator wants to increase the output from PV array 26 , the operator can set controller 42 to lower the temperature of the circulating fluid. Controller 42 lowers the circulating fluid temperature by increasing the flow of fluid to heat transfer device 50 from second fluid reservoir 46 and/or decreasing the flow of fluid from first fluid reservoir 44 , until the desired circulating fluid temperature (T.sub.d) is achieved, so long as the desired fluid temperature (T.sub.d) is greater than or equal to the second fluid temperature (T.sub.low). In this scenario, multiple temperature sensors 52 provide fluid temperature feedback to controller 42 to help the circulating fluid reach and maintain the desired temperature (T.sub.d).
[0034] If the operator wants to decrease the output from PV array 26 , the operator can set controller 42 to raise the temperature of the circulating fluid. Controller 42 raises the circulating fluid temperature by decreasing the flow of fluid to heat transfer device 50 (upper unit) from second fluid reservoir 46 and/or increasing the flow of fluid from first fluid reservoir 44 , until the desired circulating fluid temperature (T.sub.d) is achieved, so long as the desired fluid temperature (T.sub.d) is less than or equal to the first fluid temperature (T.sub.high). Again multiple temperature sensors 52 provide fluid temperature feedback to controller 42 to help the circulating fluid reach and maintain the desired temperature (T.sub.d).
[0035] Finally we consider sunlight levels that are not steady, but an operator who wishes to generate a consistent amount of power. If light levels decrease which may be measured with light level sensor 54 , the operator can increase output by setting controller 42 to lower the temperature of the circulating fluid, as described above. And if light levels later increase, the operator can decrease output by setting controller 42 to raise the temperature of the circulating fluid, as is described above.
[0036] An alternative embodiment of the invention with third fluid reservoir 48 containing fluid assumed to be at a higher temperature than first fluid reservoir 44 works much the same way, but with three possible fluid flows to heat transfer device 50 for controller 42 to manage, along with a greater range of temperatures that the circulating fluid can achieve.
[0037] In an alternate embodiment, heat transfer device 50 can be constructed from a series of two standard double-flow valves, where the first standard double-flow valve combines two of the fluid flows, and the second standard double-flow valve combines the third fluid flow with this combined fluid flow.
[0038] In any embodiment of this invention the fluid exiting PV array 26 may be at a higher temperature than when it entered PV array 26 . The second heat transfer device 50 (lower unit) can be used to extract this extra heat for some additional purpose, or use the extra heat to condition the circulating fluid for return to one or more fluid reservoirs.
[0039] For any given PV technology it is simple to calculate (or measure) the amount of electrical output change produced by a fixed change in circulating fluid temperature, allowing one to model and predict the amount of control a dynamic solar array will produce. Conversely one can calculate the type of dynamic solar array inputs, reservoir temperatures, flow rates and PV material necessary to produce a given level of output control.
[0040] Several descriptions and illustrations have been presented to aid in understanding the structure and functioning of the present invention. One skilled in the art will realize that numerous changes and variations are possible without departing from the spirit of the invention. Each of these changes and variations is within the scope of the present invention. | A method to control the temperature of a circulating fluid and thereby control the electrical output of a PV array is provided along with an apparatus for doing so which adds simple mechanical, data measurement and control elements to prior art systems. Given a set amount of sunlight, electrical output from a solar PV array will change if the temperature of the array changes. One can change the temperature of a PV array by circulating a fluid through a loop in thermal contact with the array. Controlling the temperature of this circulating fluid, allows one to control the electrical output from the array. | 8 |
FIELD OF THE INVENTION
This invention relates to solids-liquid separating centrifuges which have a rotary bowl including a screen section, a rotary helical conveyor mounted coaxially therein and means for rotating the bowl and conveyor about their common axis in the same direction at a differential speed. More particularly, the invention relates to improvements in the screen section of the bowl of such centrifuges and to the manufacturer thereof.
BACKGROUND OF THE INVENTION
Centrifuges of the type concerned are called "screen bowl" centrifuges to distinguish them from centrifuges of the same type but without a screen section called "solid bowl" centrifuges. In some screen bowl centrifuges of the prior art, the screen section has formed all or nearly all of the bowl. In others, the screen section follows a solid bowl section in which the primary separation of solids from liquid takes place, the screening section serving to drain and dry the solids preliminary to discharge. While the invention is generally applicable to screen bowl centrifuges, it is described and illustrated herein as applied to such centrifuges of the latter form.
The screen section of screen bowl centrifuges has been typically formed as a lattice of crossing axial and radial ribs defining spaced openings in which screen inserts are secured. The ribs and screen inserts form an inner surface of substantially constant radius from the bowl axis, over which the solids are moved toward an outlet by the helical conveyor. An example of such a screen bowl centrifuge is disclosed in U.S. Pat. No. 3,401,800, where in the screen inserts have a screen portion of which the inner surface is curved at the radius of the inner surface of the cross-rib lattice and a support frame portion with side and end flanges which overlap the outer surface of the sides and ends of the opening in which the insert is placed and are secured thereto. The screen portion is formed of parallel bars secured at their ends to the frame and closely spaced to provide narrow screening slots, the ribs and slots being arranged to extend transversely to the centrifuge axis, that is, circumferentially of the bowl and bridging the opening.
Screen bowl centrifuges in accordance with said patent disclosure have had extensive commercial use despite certain shortcomings, such as rapid wearing away and breakage of the screen bars and plugging of the screen, particularly when exposed to hard, abrasive solids, as, for example, in the dewatering of coal fines. The wearing, breakage, and plugging, is, e.g., caused by wedging particles between the conveyor blade and the screen. To alleviate the plugging problem, the screen bars have been formed of tapered cross-section, so that the slots enlarge outwardly as shown in the aforesaid patent. However, this aggravates the wear problem, since the narrowest, correctly sized portion is of nearly zero depth and can be quickly worn away to an unacceptably large slot width while plugging by hard particles is not materially inhibited.
Efforts have been made to mitigate the wear and breakage problem in commercial screen bowls by the use of hard, highly wear resistant materials, such as chromium surfacing on stainless steel screen bars, or forming the bars of ceramic material or sintered tungsten carbide. The results of such efforts up to now have been disappointing. While the hard material improved wear resistance so long as it remained intact, breakage occurred too soon and too extensively. In the coated bars, cracking or breakage occurred in places where hard trapped particles were forced against it, such cracking or breaking resulting in stripping of the coating from large contiguous areas. The hard material of the bars was prone to break apart, usually near their ends. Since it was thought that pressure across bars circumferentially arranged might be the primary cause of breakage, the hard, wear resistant bars have been rearranged in some commercial machines so that they are parallel rather than normal to the bowl axis, but this has not materially helped the problem either with bars formed of, or coated with, wear resistant materials.
SUMMARY OF THE INVENTION
It has been found that a primary cause of the screen bowl screen wear, breakage and plugging problems has been hard, irregular particles in the feed which can freely penetrate part way into the screening slots but have a maximum dimension too great for the particle to pass through. Such particles, becoming wedged in the slots, increase the resistance of the screen to solids passage thereover and multiply the pressure exerted on the screen by increasing the torque load. The radial component of this pressure seeks to force the particles through the slots which they cannot pass, placing the bars under great lateral as well as radial pressure. Eventually, unless the screen is unplugged, this pressure either forces these particles to wear their way out of the grooves or hard surfacing on the bar ruptures, or the bars themselves break, under the lateral strain.
This invention provides novel features of construction of screen bowl screens which, primarily because they alleviate the hard particle wedging problem as just discussed, reduce screen plugging, wear and breakage, particularly when, as is possible and preferred, the features are used in conjunction.
In all of these features, the centrifuge has a rotary bowl including a screen section, a rotary helically bladed conveyor mounted co-axially therein, means for rotating the bowl and conveyor about their common axis in the same direction at a differential speed, means for feeding a solids-liquid slurry into the bowl and means defining an outlet from the bowl for solids moved through the screen section by the conveyor.
The first two features of the invention concern the radially inner surface of the screen means that lies between and defines the screening slots. According to one such feature, the radially inner surface of the screen means slopes between successive slots laterally toward the common axis so that one of the radially inner side edges of the slots is closer to that axis than the other. The radially inner side edge closer to the axis is the trailing edge longitudinally of the conveying face of the conveyor.
This feature is useful with slots disposed more axially than circumferentially and vice versa. In either case, the conveyor is applying circumferential as well as axial components of force to the solids. With the slots disposed more axially than circumferentially, as is preferred, such inclined surfaces offer resistance to the circumferential force components in the direction of the edge closer and tend to keep the flow of solids more nearly parallel to the slots than it would otherwise be. Any movement of solids by the circumferential force components across the slots in the opposite direction is resisted by the edge closer to the axis, which acts to guide the particle flow parallel to the slots.
On the other hand, with the slots disposed more circumferentially than axially, the path of general movement of the solids by the conveyor is more nearly across the slots, from the edge further from the axis to the edge closer to it, reducing the likelihood of particles being trapped and wedged in the slots.
According to the other such feature, the slots are disposed over the screening section, either parallel to the bowl and conveyor common axis, or at an angle thereto up to and including a 90° angle. Between slots, the radially inner surface is formed in successive portions which slope toward the common axis, so that one of the ends of these portions of the screen section are closer to the axis than their opposite ends and than the adjoining end of the succeeding portion. By virture of this construction, the slots have open ends for part of their depth at each juncture of the successive portions, these affording opportunity at the juncture intervals for particles with trapped portions sliding due to the conveying face of the conveyor to escape freely.
Preferably, the slots are arranged to extend generally longitudinally of the screen section and to extend the full axial length of the screen section. They are preferably formed of bars of abrasive resistant material arranged in sets abutted end to end to define the slots between them, the abutted ends overlying and being secured to the opposite sides of apertures of an aperture supporting bowl portion. The abutted bars provide the successive sloping inner surfaces and slot end outlets. While the bars can be secured to the supporting bowl structure in tilted position to provide the end-to-end slope, that is preferably built-in by tapering the bars end-to-end so they may be secured flat to the supporting bowl structure.
This feature greatly alleviates wear, breakage and plugging at slot ends which my studies have indicated was a primary cause of the failure of axis parallel slot screens of the prior art. The latter were generally provided in short segments inset flush with intervening support structure as are the circumferential segments in U.S. Pat. No. 3,401,800 aforesaid. Particles sliding along the short slots had to "climb" out the ends against centrifugal force applied through the overlying solids layer, which provided too difficult in many cases. Instead, they stuck, backed up and soon caused breakage and/or extreme wear.
In both this feature and the first feature discussed, the difference between maximum and minimum distances from the common axis produced by the sloping should be small enough not to interfere with close clearance between the conveyor blade and the screen inner surface. Such close clearance should be maintained to insure that the solids cake as a whole will slide over the screen surface and not form a resident layer thereon, which would seriously impair the desired dewatering action of the screen as well as substantially increasing the torque load. In preferred constructions, this difference is about 0.015 inch. When both longitudinal and lateral sloping is provided, as is preferred, the difference in distance of the inner surface from the axis will be greatest between the end corner leading and the opposite end corner trailing in the direction longitudinal of the conveying force of the conveyor.
The objective of another feature of the invention is to conform the position of the screen bowl screen slots more closely to the predominant path of movement by the conveyor of hard solids in contact with the surface of the screen means than they are when positioned in a straight path parallel to the common axis.
According to this feature of the invention, the screen section of the bowl comprises slotted screen means, the slots communicating the interior of the screen section with the interior of the bowl and lying substantially along helical paths which are at an angle to the common axis facing the solids discharge end of the screen section greater than 5°. My studies of wear patterns in screen bowl centrifuges have shown that the predominant path of movement of hard solids in contact with the screen is not a straight path parallel to the common axis, but is a helical path at an angle to the common axis. The extent of this path angle is related to the helix angle of the conveyor blade, so that, in general, the greater the helix angle, the greater the angularity of the helical particle path to the common axis, that is, the angle of the path to the common axis that faces the discharge end of the screen section.
If the conveyor blade helix angle were small enough, less than 2°, the angle of particle flow direction to the axis would be about 5° or less, insufficient to be a major contributing cause to any excessive wear or breakage. Unfortunately, such low helix angles can rarely be used for the conveyor blade. The helix angles of practical use are greater, generally considerably greater, so that the angularity to the axis of the screen contacting particle flow is greater than 5°, normally falling within the range of about 15° to 41°.
The angle of particle flow referred to, while primarily a function of the helix angle of the conveyor, is also influenced to some extent by other factors, such as surface finish of the solids contacting surfaces of the screen and conveyor, physical-chemical characteristics of the material treated and its amount of moisture, direction of screen slots, conveyor clearance and the differential speed of the conveyor to that of the bowl. However, the actual path for a given set of these factors can be located with reasonable accuracy by wear path tests. Moreover, it has been determined empirically that the actual path is predictable as within ±5° of three times the helix angle of the conveyor blade portion within the screen section, the 5° latitude covering the effects of other influencing factors such as mentioned above.
By arranging the slots so that they are closer to the path of movement of the solids contacting the screen than has previously been the case, the troublesome particles of the wedging type are moved more readily longitudinally and out the ends of the slots rather than wedging, the marked improvement in screen wear, breakage and plugging is obtained, particularly when, as is preferred, this feature is combined with others, as discussed.
DESCRIPTION OF THE PREFERRED EMBODIMENT
We first briefly describe the drawings.
FIG. 1 is a cut-away view of a screen-bowl centrifuge in accordance with the present invention.
FIG. 2 is a portion of the inside surface of the FIG. 1 centrifuge.
FIG. 3 is an enlarged view of the FIG. 2 screen elements along lines 3--3.
FIG. 4 is a cross-sectional view along lines 4--4 of the FIG. 2 screen bowl elements.
FIG. 5 is a perspective view of a screen bowl element in accordance with the present invention.
FIG. 6 is a view along the lines6--6 of the FIG. 5 screen bowl element.
STRUCTURE AND OPERATION
Referring to FIG. 1, the screen bowl centrifuge shown has a bowl designated generally 10, the peripheral wall of which has an imperforate, "solid section" 12 at one end and a perforated "screen section" 14 at the other end. Solid section 12 has a larger diameter, cylindrical outer end portion which extends for about half its length and then tapers conically to a smaller diameter equal to the lesser constant diameter of the screen section 14 at their junction.
A bowl head, designated generally 16, is bolted at its rim to the flanged outer end of solid section 12 and has a central sleeve shaft 18, coaxial with the bowl, which extends rotatably through bearing assembly 20 fixed on a mounting pedestal 22, and has fixed to its outer end a drive sheave 24 having belt drive connection to a motor (not shown) which rotates shaft 18 and the bowl. A second bowl head 26 is bolted at its rim to the flanged outer end of screen section 14 of the bowl, and has a central sleeve shaft 28, coaxial with the bowl, which extends rotatable through bearing assembly 30 fixed on a mounting pedestal 32, and is connected at its outer end to drive speed change gearing unit 34.
A helical conveyor, designated generally 36, has a cylindrical hub 38 on the exterior of which is mounted a helical conveyor blade 40 extending from the outer end of solid section 12 of the bowl to the discharge outer end of the screen section 14, with close clearance from the inner surface of the bowl sections 12 and 14. The end of conveyor hub 38 in the solid bowl section 12 has fixed thereto an integral, central sleeve shaft 42 extending coaxially into bowl sleeve shaft 18 with clearance therefrom and has an outer end portion (not shown) extending through the bearings in bearing assembly 20 in which it is rotatable mounted. The end of conveyor hub 38 in screen section 14 has fixed thereto a solid shaft 44 and extends coaxially into bowl sleeve shaft 28 with clearance, trough bearing assembly 30 in which it is rotatably mounted to the speed change gear assembly 34 to which it is operatively connected to a spliced end thereof (not shown).
Thus, the rotation of bowl 10 by the motor and drive sheave 24 rotates conveyor 36 in the same direction at slightly different speeds through speed change gearing unit 34. The conveyor may be rotated faster or slower than the bowl. In the illustrated embodiment it is driven at a slower speed than the bowl. Speed change gearing unit 34 has the usual shear pin or other torque sensing system (not shown), connected at its broken-away outer end, to prevent continued operation at excessive torque loads.
A pipe 46 fixed through a support arm 48 on pedestal 22 extends coaxially with clearance through sheave 24, bearing assembly 20, and sleeve shaft 42 into the adjacent end of conveyor hub 36. Pipe 46 is divided by an internal portion into pipes 50 and 52, pipe 50 having its discharge end located in a compartment formed between partitions in the conveyor hub 36 which is provided with outlet openings of the cylindrical portion of solid section 12 of the bowl. Pipe 52 has a reduced extension into a compartment formed between another partition in the conveyor hub and the opposite end of the hub to which compartment it discharges, and which is provided with outlet nozzles discharging to screen section 14 of the bowl. Pipe 50 is the feed pipe, for connection at its outer end to a suitable source of feed slurry (not shown). Pipe 52 is the wash liquid pipe, for connection at its outer end to a suitable source of wash water or other wash liquid (not shown).
Screen section 14 of the bowl 10 is provided with annular rows of apertures therethrough 54, which form this section of the bowl into a lattice of the axial and circumferential ribs intervening apertures 54. Preferably, as shown, the openings 54, are substantially square and are uniformly spaced apart a distance equal to their length and width dimension, which thus is the width of the ribs of the lattice. Discharge outlets 56 for the solids are provided at the outer end of the screen section. The interior of the screen section 12 up to the vicinity of discharge outlets 56 is covered by slotted screening means which is designated generally 58 and is the subject of detailed description later herein.
Bowl head 16 is provided with supports 60 between which the liquid effluent separated in solid section 12 of the bowl flows out through openings in cover plate 62 of this bowl head. These openings are partially covered by weir plates (not shown) to the level of the liquid pool which it is desired to maintain in section 12.
A stationary casing 64 encloses bowl 10 and the bowl head, with clearance from enclosed rotating parts except at its end which have seals in which sleeve shafts 18 and 28 are respectively rotatable. The part of the casing above the bowl axis is separately removable from the lower part, and has hand holes with removable covers in its respective ends, to afford access to the interior. A series of annular petitions divides the casing into compartments. As can be seen from FIG. 1, these are end compartments for receiving the liquid effluent from solid section 12 and the solids from the screen section 14 of the bowl, respectively; a compartment for receiving the liquid passing through the last row of apertures 54 in the bowl of the screen section; a compartment receiving the remainder of the liquid drained from the screen section; and an over flow compartment extending there from to the effluent compartment. Means (not shown) are provided for separately removing the solids from the solids-receiving compartment and the liquid from each of the other compartments.
The centrifuge shown is designed for treatment of slurries of highly abrasive materials such as coal fines, for which purpose, preferably, the inner surface of the solid section 12 of the bowl, the inner surface of the discharge end of the screen section 14 and the solids engaging portion of the working face of conveyor blade 40 are clad with abutting tiles 66 of a hard, more abrasion resistant material than stainless steel of which the bowl is customarily formed, such as ceramic material or tungsten carbide, the tiles being cemented to the surfaces which they cover.
In operation of the centrifuge, the solids of the slurry, fed into the cylindrical portion of solids section 12 of the bowl from feed sub-pipe 50 through its discharge compartment in conveyor hub 38, settle toward the bowl inner wall under the centrifugal force. The bowl is rotated in a counterclockwise direction viewed from the right end of FIG. 1. Since the conveyor is rotated in the same direction at a slightly slower speed, the conveyor is in effect rotated in the opposite or clockwise direction relative to the bowl and pushes the settled solids from right to left in FIG. 1, out of the cylindrical portion of bowl section 12, into and through conical portion 12, into and through screen section 14 of the bowl and out its discharge apertures 56.
The effluent liquid in excess of the retained pool in solid section 12 of the bowl is discharged through apertures 62, the weirs of which are normally set for a pool inner surface diameter greater than the minimum diameter of the small end of the conical portion of section 12, which thus has this end partly out of the pool to act as a drainage deck. When wash liquid from pipe 52 is used, it is through the conveyor to the solids in the screen section 14 joins the effluent fraction which passes the screen and is collected for withdrawal in two compartments in casing 64. The close clearance previously mentioned between the conveyor blade and the bowl is from the tiles 66 which form its inner surface.
FIGS. 2 and 3 show portions of the preferred screen means 58 of the invention, on an enlarged scale from that used in FIG. 1, the scale of FIG. 3 being slightly larger than that of FIG. 2. The inside surface plan view of FIG. 2 is of a small angular and axial fragment at the discharge end of the screen section but sufficiently shows the like construction at the opposite inlet end and between the ends. As can be seen, the screen means 58 is formed of bars, designated generally 100, molded of wear resistant material, preferably sintered tungsten carbide, which are of the same dimensions including a length approximately twice that of the bowl apertures 54.
Bars 100 are arranged in axial sets extending longitudinally of the bowl of the full length of the screen section, with their ends abutted at substantially the center line of the circumferential ribs intervening the apertures 54. They are of sufficient number to extend the full axial length of the screen section between the tiles 66 forming the interior face of the smallest diameter of solid section 12 of the bowl and the tiles 66 at the outlet portion of screen section 14. These axial sets of the bars are arranged in equally spaced, parallel relation in circumferential pairs sufficient in number to cover the full inner circumference of aperture bowl section 14 between respective end sets of tiles 66, so that the bars define between those slots, designated generally 102, of substantially uniform width extending the full length of the screen section up to its discharge end, and of substantially uniform circumferential spacing about the entire circumference of the screen section.
The slots 102 which overlie axial sets of apertures 54 and intervening circumferential ribs of the bowl function as screening slots. Even where overlie the circumferential bowl ribs, they tend to drain liquid to the apertures 54 at either side of the rib. The slots overlying the axial ribs of the bowl lattice do not have this drainage function, and actually are not required in this region, which can be formed of end-abutted, solid tiles the width of the axial ribs and the same height as the bars. However, the construction shown is preferred because of other functional attributes slots in these areas, as will be described later herein.
Bars 100 are secured to the bowl ribs which they, or end portions thereof, overlie by a thin layer of cement.
Bars 100 are secured to the bowl ribs which they, or end portions thereof, overlie by a thin layer of cement 104, preferably epoxy resin cement such as its used for attaching tiles 66 to the bowl. As presently preferred, the bars are hand-laid. An angular segment of full length of the aperture bowl portion is first coated with a substantially uniform layer of the cement, the annular width of the segment being such that the laying of bars therein can be competed before the cement starts to set. A first axial set of bars is then laid from end to end of the cemented segment of the bowl, care being exercised that the bars are abutted end to end with their sides parallel to the bowl axis and in axial alignment. To facilitate the laying of subsequent axial sets of bars each bar 100 is provided on one side with a spacer 106 adjacent each end, spaced somewhat below the top of the bar and projecting laterally from the bar side a distance equal to the desired spacing between bars in the zone of the spacers. Utilizing abutment of spacers 106 with the non-spacer side of the next bar beside it to facilitate spacing and alignment, the next axial abutting bar set is laid in parallel alignment with the first, and so on until the cemented segment has been completed. Adjacent segments are then cemented and the bars applied thereto in spacer-aided alignment with bars already laid, until the entire circumference of the spaced bars. Spacers 106 are preferably as shown hemispherical with a radius equal to the desired slot width, which in the embodiment shown is about 0.03 inch, and they are most conveniently molded integral with the bars. They are spaced below the tops of the bars an amount at least approximately equal to their radius.
The section view of FIG. 3 shows a features of the invention which cannot be seen in FIG. 2, which is that the end 108 of each bar further from the inlet end of the screen section (and consequently the nearer bar end to the discharge end of the screen section shown to the left in FIG. 3) is closer to the axis of the bowl than its opposite end 110 and than the corresponding end 110 of the bar which it abuts, preferably by virtue of the bar having been molded with its top surface (as it is to be laid) having a slope toward its opposite surface from end 108 to end 110. The bars are laid uniformly with the ends 108, 110 of the bars abutting as shown, so that the upper part of each slot 102 between axial, abutted bars terminates at each juncture for a depth equal to the difference between the distance from the bowl axis of the bar ends 108 and 110 respectively, this terminated end slot portion being indicated by the dotted line d in FIG. 3. Though this difference has to be small to maintain the requisite conveyor close clearance as previously indicated, it is important to enable solid particles with portions caught in the slots to escape the slots freely out these open ends.
The cross-sectional shape of the bars may be substantially square, except as modified by the end-to-end slope just described, and except as one or both side edges may be slanted inwardly near the surface secured to the bowl to provide greater slot width. However, it is preferred to modify the shape further according to another feature incorporated in the bars as shown in FIGS. 4, 5 and 6.
As shown in FIG. 4, bars 100, in addition to the longitudinal taper just described, have a side edge to side edge taper so that one edge 112 of bar 100 is closer to the axis of the bowl than the other edge 114, preferably provided by molding another taper in thickness into the bar, from thicker edge 112 to thinner edge 114. Thus, the sidewall of each slot formed by thicker side edge 112 has its exposed edge closer to the axis of the bowl than its opposite sidewall formed by thinner bar side edge 114.
Additionally, each bar 100 may have a slight helical shape. Thus, when bars 100 are uniformly laid, bars 100 lie substantially along helical paths which are at an angle to the common axis facing the solids discharge end of the screen section greater than 5°. This path conforms to the predominant path of movement of hard solids in contact with the surface of the screen means. The extent of this path angle is related to the helix angle of the conveyor blade. This angle is generally greater than 5° and more specifically is within ±5% of three times the helix angle of the conveyor blade portion within the screen section.
The 5° latitude of the helix angle compensates for other influencing factors, such as surface finish of the solids contacting surfaces of the screen and conveyor, physical-chemical characteristics of material treated and its amount of moisture, direction of screen slots, conveyor clearance and the differential speed of the conveyor to that of the bowl. In many applications, this angle is between approximately 15° and 41°. | A screen bowl centrifuge having slots which have successive portions which slope lengthwise toward a common axis, and additionally, slots which slope laterally toward the common axis. The screen bowl centrifuge may also have slots which conform to the predominant path of solids through the centrifuge by providing helically shaped screen bowl elements. | 1 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 09/585,545 filed Jun. 2, 2000 now ABN.
This application claims the priority of German Application No. 199 25 271.8 filed Jun. 2, 1999, which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
This invention relates to a draw unit for a spinning preparation machine, particularly a regulated draw frame for cotton or chemical fibers and the like. The draw unit has at least two consecutively arranged roll pairs each having a driven roll provided with its own electromotor as well as an electronic control and regulating device to which the electromotors are connected. A respective incremental rotational displacement sensor is coupled with the driven rolls.
In a known draw unit, as disclosed in German patent document No. 196 44 560, to which corresponds U.S. Pat. No. 5,991,977, a device for preventing a reverse rotation during standstill is associated with the lower input roll.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an improved method of operating a draw unit of the above-outlined type in which, upon reverse rotation of the rolls during standstill the predetermined extent of draw of the sliver bundle is preserved in a simple manner.
This object and others to become apparent as the specification progresses, are accomplished by the invention, according to which, briefly stated, the method of operating a sliver draw unit of a spinning preparation machine includes the following steps: applying, by incremental rotary displacement sensors, signals to an electronic control and regulating device; determining from the signals the angular position and/or the rotary direction of at least one of the roll pairs of the draw unit during operation and standstill; and rotating at least one of the roll pairs into a predetermined angular position by controlling the electric motor driving that roll pair.
The incremental rotary displacement sensors are associated with the rolls at the input and with the rolls at the output of the draw unit whereby a highly responsive monitoring of the rpm and the direction of rotation of the rolls is possible to thereby permit suitable countermeasures or intervention. In particular, an undesired reverse rotation of the intake roll or the intake and mid roll is compensated for by a slight forward rotation during standstill of the outlet rolls so that locations of reduced thickness or even ruptures in the sliver are avoided. The predetermined draft of the sliver is maintained during standstill even in case of a possible reverse rotation of the input roll. The forward rotation of the intake roll causes the sliver to sag slightly which is harmless. Then, in case of a reverse rotation, the sagging region is simply pulled straight without causing a reduction in the sliver thickness or a rupture. It is a further particular advantage of the invention that based on the known position of the rolls in operation, during standstill and after switching off the machine, particularly the drive motors, the overhanging sliver is first pulled taut or set in a simple manner with the aid of the controlled motors. Thereafter the rolls are accelerated to the operational rpm, and the sliver is accelerated to the operational speed while maintaining the predetermined draft (despite an undesired reverse rotation of the intake roll that may occur). The invention eliminates the need for a mechanical or an electromechanical lock to prevent a reverse roll rotation.
The invention has the following additional advantageous features:
The electronic control and regulating device may set the sliver in or upstream of the draw unit to a predetermined draft by a suitable rpm control of the drive motor or drive motors.
During standstill of the output roll, the input roll or the input roll and the mid roll continue to rotate forward to a small predetermined extent.
The extent of the forward rotation equals at least the extent of the reverse rotation of the rolls caused by a relaxation of the sliver during standstill.
After reaching the predetermined forward rotation, the input roll or the input roll and the mid roll is placed in a standstill state.
The input rolls or the input rolls and the mid rolls and the output rolls are braked to assume standstill and subsequently the input roll or the input roll and the mid roll are slightly accelerated in the working (forward) direction.
When the machine is stopped and after the standstill state is reached, the principal electric motor (driving the output roll pair) is turned off, and then the regulating electric motor (driving the input roll pair or the input roll pair and the mid roll pair) is switched on and is subsequently switched off.
Upon stopping the machine the rpm of the principal motor is reduced to zero from the operational rpm and the rpm of the regulating motor is first reduced to a value greater than zero and thereafter is reduced to zero.
Upon turning on the motors the roll rpm's are set to correspond to a predetermined draft of the sliver.
Upon turning on the motors, deviations from the predetermined positions (desired values) are compensated for.
The output rolls are brought into a predetermined position.
The input rolls or the input rolls and the mid rolls are brought into a predetermined position.
After setting the rolls to predetermined (desired) positions, the rolls are accelerated to the operating rpm.
The predetermined rotary displacement is between zero and 4 mm.
The predetermined rotary displacement is zero; the reverse rotation may be eliminated by a slight acceleration in the working direction.
The predetermined rotary displacement is zero; the reverse rotation corresponds to the small rotary displacement in the working direction.
The displacement of the sliver in the working direction is approximately between 0.1 and 4 mm.
The sliver is accelerated in the principal draw field during standstill of the output rolls by a small rotation of the input roll or the input roll and the mid roll.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG 1 a is a schematic side elevational view of a regulated draw frame for practicing the invention.
FIG. 1 b is an enlarged partial schematic side elevational view of roll pairs of FIG. 1 a.
FIG. 2 is a schematic top plan view of the lower rolls of the draw unit of FIG. 1 a, including a block diagram.
FIG. 3 is a perspective view of an incremental rotary displacement sensor.
FIG. 4 illustrates a signal pattern of the incremental rotary displacement sensor of FIG. 3 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 a illustrates a draw frame 1 which may be an HSR model manufactured by Trützschler GmbH & Co. KG, Mönchengladbach, Germany. The draw frame 1 includes a draw unit 2 having a draw unit inlet 3 and a draw unit outlet 4 . The slivers 5 are taken from non-illustrated coiler cans, they are introduced into a sliver guide 6 and, pulled by the withdrawing roll pair 7 , 8 , they are advanced through a measuring member 9 . The draw unit 2 is a 4-over-3 construction, that is, it has three lower rolls, namely, a lower output roll I, a lower mid roll II and a lower input roll III, as well as four upper rolls 11 , 12 , 13 and 14 . The working direction of the draw unit 2 is designated at A.
Also referring to FIG. 1 b, in the draw unit 2 the sliver bundle portion 5 ′ is drawn in a preliminary drawing field and the sliver bundle portion 5 ″ is drawn in the principal drawing field. The roll pairs 14 , III and 13 , II form the preliminary drawing field whereas the roll pair 13 , II and the roll assembly 11 , 12 , I form the principal drawing field. The drawn slivers 5 are admitted in the draw unit outlet 4 to a sliver guide 10 and are pulled by delivery rolls 15 , 16 through a sliver trumpet 17 in which the slivers are combined into a drawn sliver 18 which is subsequently deposited in coiler cans.
The withdrawing rolls 7 , 8 , the lower input roll III and the lower mid roll II which are mechanically connected to one another, for example, by a toothed belt, are driven by a regulating motor 19 whose rpm may be based on an inputted desired value. The upper rolls 13 and 14 co-rotate with their respective lower rolls. The lower output roll I and the withdrawing rolls 15 , 16 are driven by a principal motor 20 . The regulating motor 19 and the principal motor 20 are each provided with a respective regulator 21 and 22 . The regulation (rpm regulation) is effected by a closed regulating circuit. The regulating motor 19 and the principal motor 20 are associated with a respective tachogenerator 23 and 24 . At the draw unit outlet 4 the cross section of the exiting sliver 18 is determined by an outlet measuring member 25 disposed at a sliver trumpet 17 . A central computer unit 26 (control and regulating device), for example, a microcomputer including a microprocessor, applies the desired setting values for the regulating motor 19 to the regulator 21 . The measuring values of both measuring members 9 and 25 are applied to the control and regulating device 26 during the drawing operation. The desired value for the regulating motor 19 is determined in the central computer unit 26 from the measuring values of the inlet measuring member 9 and the desired value for the cross section of the exiting sliver 18 . The measuring magnitudes of the outlet measuring member 25 serve for monitoring the exiting sliver 18 . With the aid of the regulating system fluctuations in the cross section of the inputted slivers 5 may be compensated for by a suitable regulation of the drawing process to thus obtain an evening of the sliver 18 . A pressing bar 30 is provided in the principal draw field for deflecting the sliver bundle 5 ″.
In FIG. 1 b the arrow B indicates the undesired direction of motion of the sliver bundle 5 , 5 ′, 5 ″ as relaxation of the sliver bundle takes place during standstill. The arrows C, D, E, F, G, H and K show, during operation, the direction of rotation of the respective rolls III, II, I, 14 , 13 , 12 and 11 .
According to the invention, after all rolls of the draw unit 2 are braked to a standstill, the input rolls III, 14 and the mid rolls II, 13 are accelerated slightly in the working direction A, while the output rolls I, 12 , 11 remain stationary. As a result, the entire sliver bundle 5 , 5 ′, 5 ″ is slightly shifted in the working direction A, for example, to an extent of 3 to 4 mm, whereby the sliver bundle portion 5 ″ is relaxed in the principal draw field and may sag slightly as indicated at 5 1 . Upon an undesired reverse rotation of the rolls III, 14 and II, 13 —that is, a rotation in a direction opposite the arrows C, D, F and G—and thus upon an undesired motion of the sliver bundle in the direction B, the sliver bundle 5 ″ is merely straightened without interfering with its structure and particularly, without interfering with the drawing thereof.
Turning to the schematic top plan view of FIG. 2, the lower input roll III and the lower mid roll II are coupled to one another with a gearing whose transmission ratio corresponds to a predetermined preliminary draw. The lower input roll III and the lower output roll I are coupled with respective incremental rotary displacement sensors 31 and 32 . The rpm's of the regulating electric motor 19 and the main electric motor 20 are regulated by the control and regulating device 26 in such a manner that in the principal drawing field between the mid roll pair II, 13 and the output roll assembly I, 11 , 12 a draft up to the desired fine value occurs while, at the same time, mass fluctuations of the incoming sliver bundle 5 are compensated for to the extent possible.
With further reference to FIG. 2, the electric motor 19 drives the two rolls III and II via a common transmission shaft 33 . The transmission stages include toothed belts and gears transmitting the torque from the shaft 33 to the shafts 46 and 47 of the respective rolls III and II. The transmission gears interposed between the motor 19 on the one hand and the rolls II, III, on the other hand, are designated at 34 - 41 whereas the drive belts are designated at 42 - 45 . The incremental rotary displacement sensor 32 associated with the lower output roll I and the incremental rotary displacement sensor 31 associated with the lower input roll III are connected by respective conductors 49 and 50 with the control and regulating device 26 to which a memory 54 is connected. In the arrangement shown in FIG. 2, the control and regulating device 26 may be a microcomputer which serves for controlling the machine operation and also serves for regulation to compensate for product irregularities. In particular, the electronic control and regulating device 26 is utilized for performing the method according to the invention. The lower rolls III, II, I have a respective rpm of, for example, 1400, 2000 and 7200 and a respective diameter of, for example, 35 mm, 35 mm and 40 mm. At the output of the roll assembly I, 11 , 12 the running speed of the sliver is approximately 900 m/min at an rpm of 7200 of the lower output roll I.
The task to compensate for a reverse rotation of the rolls III, 14 and II, 13 during standstill of the machine is achieved by means of the incremental rotary displacement sensors 31 and 32 , in conjunction with the electronic control and regulating device 26 . A reverse rotation occurs practically always and is caused by the relaxation of the sliver bundle and the drive belts upon machine stoppage. The incremental rotary displacement sensors 31 and 32 (illustrated in FIG. 3) generate a pulse series whose frequency is proportional to the rpm of the roll to be monitored. The rotary displacement sensors 31 , 32 are of the type by means of which the direction of rotation, the angular position, the rpm and the speed of the roll may be determined. Expediently, a magnetic incremental rotary displacement sensor 31 , 32 is used in which a measuring shaft 51 and an encapsulated measuring head 52 are provided. The electric output of the sensor is designated at 53 .
As shown in FIG. 4, two sinusoidal signals 55 whose phase is shifted by 90° are converted into square wave pulses in a 1:1 frequency ratio and are emitted at two outputs whereby a rotational differentiation is feasible.
The measures according to the invention render additional mechanical aids such as freewheeling clutches or motor brakes unnecessary. For performing the invention, a high-resolution detection of the rpm's and the angular position of the roll axes in the draw unit need to be obtained. Such a detection is effected by the rotary displacement sensors 31 , 32 at the input and output rolls of the draw unit.
During operation, first the drives are braked until stoppage of the output roll I in the draw unit 2 . A reverse rotation of the input roll III would lead to a thickness reduction in the sliver. To prevent such an occurrence, prior to switching off the drives, the input roll III (driven by the regulating motor 19 ) is, while the output roll I is stationary, further driven for an additional determined forward angular displacement to feed the sliver in the direction A. As a result, the sliver is relaxed in the principal drawing field and the reverse rotation of the input roll III upon switching off the drive is thus compensated for. Since upon switching off the drives the angular position of the rotary shafts in the draw unit change, the position of the roll shafts is detected by the rotational displacement sensors 31 , 32 even during standstill, that is, after switching off the drives. After again switching on the drives, these positional changes are first compensated for and thereafter the operating rpm's of the machine are set.
The invention was described in connection with an example of a slight forward rotation in the working direction A of the input roll III or, in case of a mechanical coupling, the input roll III and mid roll II, while the output roll I is stationary. It is to be understood that the invention also includes an embodiment in which a slight reverse rotation against the working direction A—that is, in the direction B according to FIG. 1 b —of the output roll I is effected while the input roll III or (upon mechanical coupling) the input roll III and the mid roll II are stationary.
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. | A method of operating a sliver draw unit of a spinning preparation machine includes the following steps: applying, by incremental rotary displacement sensors, signals to an electronic control and regulating device; determining from the signals the angular position and/or the rotary direction of at least one of the roll pairs of the draw unit during operation and standstill; and rotating at least one of the roll pairs into a predetermined angular position by controlling the electric motor driving that roll pair. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Patent Application 60/767,076, filed on Mar. 1, 2006.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
Not Applicable.
FIELD OF THE INVENTION
The present invention relates generally to beverage cups and, more particularly, to a novel coffee cup sleeve.
BACKGROUND AND DESCRIPTION OF THE PRIOR ART
With the increase in popularity of retail coffee establishments such as Starbucks, Seattle's Best Coffee, Dietrich's Coffee, and the like, the use of disposable paperboard coffee cups has increased dramatically. Such cups transmit heat fairly well, and as a result various types of disposable coffee cup sleeves have been devised to eliminate the previous practice of “double cupping,” wherein an additional paperboard coffee cup was used to insulate the heat of the coffee from the consumer's hand. Such disposable sleeves use far less paper or paperboard than an additional cup, yet provide even better insulating characteristics. As a result, use of such disposable sleeves has saved a significant amount of paperboard material and has considerably benefited the environment.
Examples of such sleeves can be found in the following references: U.S. Pat. No. 6,152,363 to Rule, Jr. on Nov. 28, 2000; U.S. Pat. No. 5,667,135 to Schaefer on Sep. 16, 1997; U.S. Pat. No. 5,857,615 to Rose on Jan. 12, 1999; and U.S. Pat. No. 6,315,192 to Marlow on Nov. 13, 2001. Of particular interest in the present invention is U.S. Pat. No. 6,182,855 to Alpert on Feb. 6, 2001, which teaches a translucent or transparent sleeve such that an indicia printed on the cup may be seen therethrough. Also, U.S. Pat. No. 6,814,253 to Wong on Nov. 9, 2004 teaches an opaque sleeve having a surface suitable for printing an indicia thereon.
While such sleeve devices have benefited environment by reducing waste, prior art sleeves are still designed to be disposed of after use. Moreover, if a consumer retains such a sleeve with the intention of re-using it, and since such devices are typically made from paperboard or corrugated paper stock, they are prone to becoming stained with coffee or other foodstuffs. Even if a customer's favorite drink has been printed on such a sleeve for the benefit of the barista making the coffee drink, the device is only re-usable a finite number of times before its living hinges wear-out or it becomes unsightly and an embarrassment.
To reduce still further the environmental burden caused by the large number of such disposable sleeves being manufactured, used once, and then discarded, other sleeve devices have been invented that are either designed to be non-disposable or biodegradable. Such devices are described in U.S. Pat. No. 5,320,249 to Strech on Jun. 14, 1994; U.S. Pat. No. 6,286,709 to Hudson on Sep. 11, 2001; and U.S. Pat. No. 5,746,372 to Spence on May 5, 1998.
A significant drawback to the biodegradable devices is that one device must be used and purchased with each beverage purchase. As such, these products are still relatively expensive to supply to each customer and result in greater expense for the retail coffee establishment. Customarily, such establishments are typically expected to furnish such sleeves for free to their customers upon request.
A significant drawback to the non-disposable devices is that, when engaged with a beverage cup, they are typically opaque and do not allow a barista preparing the coffee drink to see the customization details that are typically written on the beverage cup by the order taker. As a result, such devices are impractical to use and would cause disruption in the normal work flow of a retail coffee establishment by requiring the barista to perform the extra labor step of removing the sleeve temporarily in order to complete the preparation of the beverage. But it is a further drawback that the order taker must write the customer's drink order on a new cup every time the customer visits, even when the customer orders the same drink with every visit.
As such, a non-disposable, translucent or transparent sleeve is needed. Such a sleeve would be made from a heat insulating material, would be relatively easy to clean, and would allow for quick reading of a customized drink notations printed thereon. Yet the printing on such a needed device would necessarily be protected from moisture, such as from liquid splashed or dripped down the side of the sleeve. The present invention accomplishes these objectives.
SUMMARY OF THE INVENTION
The present invention is an insulating sleeve combination for a frusto-conical beverage cup, such as is commonly served in retail coffee establishments and the like. Such cups, which are made in various sizes, all include an outer peripheral surface. The combination of the present invention includes an opaque frusto-conical inner sleeve and a frusto-conical outer sleeve. Preferably, at least a portion of the outer sleeve is transparent, such that indicia on the inner sleeve is visible therethrough. Alternately, at least a portion of the outer sleeve may be translucent, whereby the indicia is at least partially visible therethrough. The outer sleeve, in such embodiments, may be made from a silicon rubber material, for example, that has excellent heat insulation properties and serves to insulate a person's hand from a majority of the heat emanating from the cup. Alternately, the outer sleeve may be made from a clear vinyl or other similar translucent or transparent material. The outer surface of the outer sleeve may includes a textured gripping surface, facilitating the manual grasping of the combination by the user.
In use, the consumer typically acquires the present invention in a substantially flat configuration with the inner sleeve engaged within the outer sleeve. The consumer may then remove the inner sleeve and customize a desired beverage order thereon by printing with a pen or applying a pre-printed label thereto. The consumer then engages the inner sleeve with the outer sleeve. Upon ordering, the consumer merely hands the combination of the present invention to the order taker, who reads the pre-printed beverage-indicating indicia on the inner sleeve through the outer sleeve, inserts an appropriate cup therein, and completes the order. The consumer receives the beverage in the cup and, upon finishing the beverage, removes the combination of the present invention from the cup. The process can be repeated day to day, as the outer sleeve is easy to clean. Further, if the consumer ever desires to change his indicated beverage, an alternate inner sleeve can be prepared from conventional card-stock or paperboard material and substituted with the old inner sleeve. Still further, seasonal inner sleeves may be provided to consumers who still retain the outer sleeves, giving the consumer increased ability to express themselves with various styles of inner sleeves. Inner sleeve designs can be supplied at the retail beverage establishments, though pre-cut templates that the user may customize as desired, such as by printing through a color printer or the like, by other sponsors, or by any other of a wide variety of means.
The present invention provides a reusable beverage sleeve that not only protects the environment by reducing the number of disposable sleeves that are used, but also provides a streamlined ordering method for the user and retail beverage establishments. The present device, while more expensive to produce than any one disposable sleeve, actually saves the beverage establishment money by allowing fewer disposable sleeves to be printed. Further, the retail beverage establishment may sell the present invention, rather than providing a disposable sleeve to their customers gratis. A wide variety of designs of inner sleeves may be printed, as well, thereby allowing consumers to express their individuality. Further, inner sleeves may be provided blank for the consumer to print themselves, making the number of inner sleeve combinations endless. Still further, the present invention is even more effective at insulating a consumer's hand from the heat of a hot beverage than a disposable sleeve alone. Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective drawing of the invention, illustrating a combination of an inner sleeve fully engaged with an outer sleeve as together engaged to a beverage cup;
FIG. 2 is a partially cut-away perspective drawing of the invention;
FIG. 3 is a cross-sectional view of the invention, taken generally along lines 3 - 3 of FIG. 2 ;
FIG. 4 is an exploded front elevational view of the invention, illustrating the inner sleeve separated from the outer sleeve;
FIG. 5 is a top plan view of the outer sleeve of the invention, illustrating the outer sleeve in a circular configuration for accepting insertion of the inner sleeve and the cup;
FIG. 6 is a top plan view of the invention, illustrating both the inner sleeve and outer sleeve in a flat configuration;
FIG. 7 is a front elevational view of the outer sleeve of the invention, illustrating a gripping texture on the outer surface thereof;
FIG. 8 is a front elevational view of the inner sleeve of the invention, illustrating the inner sleeve as made from a flat arcuate section of paper stock material; and
FIG. 9 is a partial perspective view of the invention, illustrating an embodiment of the invention wherein the outer sleeve includes a U-shaped handle formed integrally therewith.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrations an insulating sleeve combination 10 for a frusto-conical beverage cup 20 , such as is commonly served in retail coffee establishments such as Starbucks Coffee. Such cups 20 , of various sizes, all include an outer peripheral surface 25 .
The combination 10 includes an opaque frusto-conical inner sleeve 30 and a frusto-conical outer sleeve 80 . The inner sleeve 30 includes an inner surface 35 for engagement with the outer peripheral surface 25 of the cup 20 , an outer surface 40 adapted for accepting printed indicia 50 thereon, a top edge 60 , and a bottom edge 70 . The inner sleeve 30 may be formed from an arcuate section 130 ( FIG. 8 ) of cardboard or cardstock paper, for example, that has a top edge 140 , a bottom edge 150 , and two side edges 160 that are fixed together. As such, the arcuate section is curved around itself to form the frusto-conical inner sleeve 30 . Further, a pair of creases 180 may be formed into the arcuate section 130 between the top and bottom edges 140 , 150 and at opposing sides thereof so that the inner sleeve 30 formed thereby may be folded substantially flat configuration for storage, transport, and the like ( FIG. 6 ).
The outer sleeve 80 includes an inner surface 90 for engagement with at least a portion of the outer surface 40 of the inner sleeve 30 , an outer surface 100 , a top edge 110 and a bottom edge 120 . The outer sleeve 40 has an inside diameter sufficient to allow at least partial insertion of the inner sleeve 30 within the outer sleeve 80 such that the inner and outer sleeves 30 , 80 are coaxially aligned. The outer sleeve 80 may further be tapered so that the thickness thereof proximate the bottom edge 120 is substantially thinner than the thickness thereof proximate to the top edge 110 (not shown). As such, insertion of the cup 20 and the combination 10 into a typical vehicle cup holder (not shown) is facilitated.
A pair of living hinges 170 may be formed into the outer sleeve 80 between the top and bottom edges 110 , 120 thereof. Each living hinge 170 is positioned at opposing areas of the inner surface 90 such that the outer sleeve 80 may be collapsed to form a generally flat arc shape ( FIGS. 6 and 7 ). As such, when the inner sleeve 30 is fully engaged in the outer sleeve 80 , and with each of the creases 180 of the inner sleeve 30 aligned with one of the living hinges 170 of the outer sleeve, the combination 10 may be collapsed to a generally flat orientation, such as while the combination 10 is not being used. However, in order to use the combination 10 , by pressing each living hinge 170 inward, the inner and outer sleeves 30 , 80 both assume a generally circular configuration in order to allow receipt of the cup 20 therein.
The height d 1 of the outer sleeve 80 generally corresponds to the height d 2 of the inner sleeve 30 . As such, the inner sleeve 30 may be completely contained within the outer sleeve 80 , the outer surface 40 of the inner sleeve 30 completely covered by the outer sleeve 80 . In such an embodiment, the top edge 60 of the inner sleeve 30 is substantially co-planar with the top edge 110 of the outer sleeve 80 , and the bottom edge 60 of the inner sleeve 30 is substantially co-planar with the bottom edge 120 of the outer sleeve 80 .
In an alternate embodiment of the invention, however, the bottom edge 120 of the outer sleeve 80 extends past the bottom edge 70 of the inner sleeve 30 , thereby defining a bottom lip portion 190 of the outer sleeve 80 . The bottom lip portion 190 of the outer sleeve 80 , in such an embodiment, may contact the outer peripheral surface 30 of the beverage cup 20 . As such, the weight of the beverage cup 20 forces full frictional engagement of the inner sleeve 30 with the outer sleeve 80 , but the outer sleeve 80 cannot extend past the inner sleeve 30 since the lip portion 190 presses against and retains the bottom edge 70 of the inner sleeve 30 .
In yet another alternate embodiment of the invention, the top edge 110 of the outer sleeve 80 also extends past the top edge 60 of the inner sleeve 30 , thereby defining a top lip portion 200 of the outer sleeve ( FIGS. 1-3 ). The top lip portion 200 of the outer sleeve may contact a portion of the peripheral surface 25 of the cup 20 as it encompasses the top edge 60 of the inner sleeve 30 . As such, when the user desires to remove the combination 10 from the beverage cup 20 , such as when the beverage cup 20 is empty, the top lip portion 200 pulls the inner sleeve 30 away from its frictional engagement with the cup 20 . Without such a top lip portion 200 , upon pulling the outer sleeve 80 downward away from the cup 20 , the inner sleeve 30 may become disengaged with the outer sleeve 80 and remain frictionally engaged to the cup 20 . When the outer sleeve 80 is formed from a transparent or translucent silicon rubber, or the like, the frictional engagement between the inner sleeve 30 and the outer sleeve 80 is typically greater than the frictional engagement between the inner sleeve 30 and the peripheral surface 25 of the cup 20 . However, with certain combinations of materials for the inner and outer sleeves 30 , 80 , the frictional engagement therebetween is not sufficient to overcome the frictional engagement between the inner sleeve 30 and the peripheral surface 25 of the cup 20 , and in such instances having the top lip portion 200 is desired. Each bottom lip portion 190 and top lip portion 200 has a flat inward-facing surface 205 that substantially fully contacts the peripheral surface 25 of the cup 20 ( FIG. 3 ).
Preferably, at least a portion of the outer sleeve 80 is transparent, such that indicia 150 on the inner sleeve 30 is visible therethrough ( FIGS. 1 and 2 ). Alternately, at least a portion of the outer sleeve 80 may be translucent, whereby the indicia 150 is at least partially visible therethrough. The outer sleeve 80 , in such embodiments, may be made from a silicon rubber material, for example, that has excellent heat insulation properties and serves to insulate a person's hand from a majority of the heat emanating from the cup 20 . Alternately, the outer sleeve 80 may be made from a clear vinyl or other similar translucent or transparent material. The vinyl material may be doped with a scented material to overcome the smell of vinyl out-gassing when heated, such as when engaged to a cup containing a hot beverage. Such a scented material may be, for example, chocolate, vanilla, mint, cinnamon, caramel, hazelnut, cherry, coffee, or other suitable scents.
A U-shaped handle 210 ( FIG. 9 ) may further be included, the U-shaped handle 210 extending from one side of the outer surface 100 of the outer sleeve 80 , preferably between the two living hinges 170 . As such, the cup 20 and the combination 10 may be manually supported by a user grasping the handle 210 . The U-shaped handle 210 may be formed integrally with the outer sleeve 80 , or may be attached thereto through suitable bonding methods known in the art. The U-shaped handle may be completely filled-in, if desired, to make a tab-shaped handle. Alternately, the outer surface 100 of the outer sleeve 80 may includes a textured gripping surface 105 , facilitating the manual grasping of the combination 10 by the user.
In use, the consumer typically acquires the present invention in its flat configuration with the inner sleeve 30 engaged within the outer sleeve 80 . The consumer or a store employee may then remove the inner sleeve 30 from the outer sleeve 80 and print a customized drink notation thereon by printing with a pen or applying a pre-printed label 150 thereto. The consumer or employee then engages the inner sleeve 30 with the outer sleeve 40 . Upon ordering, the consumer merely hands the combination 10 of the present invention to the order taker, who reads the pre-printed beverage-indicating indicia 150 on the inner sleeve 30 through the outer sleeve 80 , inserts an appropriate cup 20 therein, and completes the order. The consumer receives the beverage in the cup 20 and, upon finishing the beverage, removes the combination 10 of the present invention from the cup 20 . The process can be repeated day to day, as the outer sleeve 80 is made from an easy-to-clean material.
Further, if the consumer ever desires to change his indicated beverage, an alternate inner sleeve 30 can be prepared from conventional card-stock or paperboard material and substituted with the old inner sleeve 30 . Still further, a seasonal inner sleeve 30 may be provided to consumers who still retain the outer sleeve 80 , giving the consumer increased ability to express themselves with various styles of inner sleeves 30 . Inner sleeve 30 designs can be supplied at the retail beverage establishments, through pre-cut templates that the user may customize as desired such as by printing through a color printer or the like, by other sponsors, or by any other of a wide variety of means. Indeed, several such combinations 10 may be purchased by the consumers, one for each of the consumer's favorite beverages. The inner sleeves 30 of each such combination 10 may be customized to represent the favorite beverage. For example, a summer scene with bright colors may be used to signify a light tea drink, or the like, while a winter scene with frost-covered trees may be printed on the inner sleeve to represent a hot coffee beverage.
While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. For example, the cross-section of the outer sleeve 80 may be varied, taking on a C-shape, an L-shape, a 7-shape or a straight shape. Further, the materials used to form the inner and outer sleeves may be varied by those skilled in the art as needed for various styles or types of cups 20 Accordingly, it is not intended that the invention be limited, except as by the appended claims. | An insulating sleeve combination for a frusto-conical beverage cup having an outer peripheral surface is disclosed, as well as a method of use thereof. The combination includes an opaque frusto-conical inner sleeve and a frusto-conical outer sleeve. At least a portion of the outer sleeve is transparent or translucent, such that indicia on the inner sleeve is visible or at least partially visible therethrough. The outer surface of the outer sleeve may includes a textured gripping surface, facilitating the manual grasping of the combination by the user. As such, a customized inner sleeve may be marked to indicate a favorite drink of the user, for example, with the markings being visible through the outer sleeve. The combination of the present invention is designed for repeated use, rendering prior art disposable sleeves unnecessary. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
This is a continuation of application Ser. No. 09/585,253, filed May 31, 2000, now continuation of U.S. Pat. No. 6,511,257 B1, issued Jan 28, 2003.
STATEMENTS AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
(Not Applicable)
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a reusable mat system for the construction of load bearing surfaces, such as temporary roadways and equipment support surfaces, over unstable or unsubstantial terrain. More particularly, the present invention relates to a reusable system of durable, interlocking individual mats which can be quickly and easily installed in a single application to construct temporary roadways and equipment support surfaces, and which can thereafter be easily removed and stored until needed again. More particularly still, the present invention relates to a reusable mat system comprising generally identical mats constructed of thermoplastic resins or other moldable materials, which interlock on all sides to form stable and continuous load bearing surfaces, and which exhibit favorable traction characteristics.
2. Description of the Related Art
When performing operations with heavy equipment in a remote location, it is often necessary to provide a firm, stable and continuous surface to support such heavy equipment. For example, when drilling a well in a remote location, it is often necessary to provide work surfaces used during the drilling process. It is also advantageous to provide one or more roadways to permit ingress to and egress from said remote location. Such a surface must provide sufficient support for the equipment and personnel involved in the work process, and must be able to withstand severe weather. Further, such a support surface must be capable of being quickly and easily installed, and thereafter being easily removed and reused at other locations.
Wooden boards or planks have historically been used to construct temporary roadways and equipment support surfaces in remote or undeveloped areas where the terrain lacks sufficient integrity to adequately support trucks and other heavy equipment. Such boards were generally placed end to end, or side by side, to form a continuous load supporting surface. While individual wooden boards or planks have been used to construct support surfaces for some time, this method of building roadways and other load bearing surfaces suffers from some very significant disadvantages.
Because such a large number of individual wooden boards are generally required to construct a typical roadway or equipment support surface, the use of wooden boards can be very labor intensive, since each board must first be individually positioned, and thereafter nailed or otherwise secured in place. Removal of said individual boards can also be a very time consuming and labor intensive process, since each board must be separated or pulled apart prior to being removed from the location. Each individual board must also be loaded onto a truck or other means of transportation prior to being removed from the particular location or work site.
In order to overcome the aforementioned shortcomings associated with the use of individual boards, a variety of mat systems have been developed for the construction of temporary roadways and support surfaces. These mat systems typically utilize prefabricated, multi-layered wooden mats which can be installed in a variety of configurations to create roadways or other support surfaces. These mats, which are constructed of a number of individual boards or planks affixed together in a variety of configurations, generally interconnect or inter mesh with one another to form a continuous, or nearly continuous, support surface.
While such conventional mat systems may represent an improvement over the use of individual boards for the construction of roadways and other equipment support surfaces, the aforementioned conventional mat systems suffer from a number of serious shortcomings. Although such conventional mats may reduce labor requirements compared to individual wooden boards, significant amounts of time, effort and manpower are still required to install said mats at a remote location since most, if not all, of said conventional mat systems require the use of multiple layers. In other words, an initial layer must first be installed, then at least one additional layer of mats must be installed over said first layer. This multiple layer requirement leads to significant redundancy of effort in connection with both the installation and removal of said mats.
Additionally, the design of conventional mat systems can lead to degradation of the ground underlying said mats, as well as the structural integrity of the mats themselves. Because the individual mats of conventional mat systems are generally constructed of various configurations of wooden boards or planks, conventional mats contain gaps or seams between said boards and/or planks. As rain falls on said mats, the rain water passes through the seams of said mats and mixes with the underlying soil to make mud. Trucks and other heavy equipment passing over the mats place a downward load on said mats, which in turn causes mud to be pumped up through the numerous gaps or seams of the mats. This pumping action creates voids beneath the mats which, over time, can lead to severe deformities in the roadway surface. Because the mats bridge over these underlying voids, the mats thereafter have a tendency to break or splinter when subjected to loading from above, especially after such wooden mats dry out.
Conventional wooden mats also suffer from significant rotting problems, since the mats can become inundated with rain water and various other contaminants from above, as well as mud from below. This mixture of water, mud and other contaminants will often invade into the seams or gaps between the boards of said mats, causing the wooden mats to rot from within. As a result, just as with individual boards, conventional mats must be frequently repaired and, in some cases, entirely replaced. Although conventional mat systems are designed to be reusable, the mats are still subject to significant repair and replacement expense. The design of these conventional mats can also lead to significant environmental problems, because mud and other contaminants can saturate the mats and collect within the numerous seams or gaps of said mats.
Yet another shortcoming with existing mat systems is the failure of individual mats to lock or interconnect with one another on all sides. Because the intended use of the mats dictates that the roadway or support surface will be subjected to loading from heavy equipment, often in different lateral directions, it is advantageous for individual mats to interconnect on all sides. This will prevent the individual mats from separating or “walking apart” from one another, and will promote a continuous and uniform work surface.
Mat systems have been known in the art for some time. U.S. Pat. No. 2,819,026 to Leyendecker, describes a mat system wherein individual mats interconnect on two sides, and which further requires the use of a strap means for retaining said mats in a desired position.
U.S. Pat. No. 4,462,712 to Penland describes a mat system comprised of individual mats which contain interlocking fingers and recesses, but which interlock on only two sides. Similarly, U.S. Pat. No. 5,087,149 to Waller and U.S. Pat. No. 4,600,336 to Waller also disclose mat systems employing individual mats with alternating offset extensions and recesses along the edges of said individual mats. However, said patents describe offset extensions comprised of individual planks which are subject to warpage, cracking or splintering when exposed to environmental elements, as well as loading from trucks or other heavy equipment using the work surface. Moreover, unlike the present invention, these offset extensions often need to be nailed in place to be secured within the recess of an adjacent mat. The referenced patents to Waller also describe the additional step of securing a plank or board between the individual mats, which significantly increases labor requirements associated with these mat systems.
U.S. Pat. No. 5,273,373 to Pouyer; U.S. Pat. No. 5,316,408 to Stanley, et al.; U.S. Pat. No. 4,875,800 to Hicks and U.S. Pat. No. 4,973,193 to Watson et al. all describe mat systems which are installed in multiple layers or stages. This factor makes the installation process significantly more complicated than that of the present invention, and greatly increases labor costs associated with said installation.
U.S. Pat. No. 4,629,358 to Springston discloses a mat system for the construction and repair of airfield surfaces. The individual mats described in the '358 patent are fiberglass—reinforced plastic composite mats which include hollow inorganic silica spheres for weight reduction purposes. Although the mats disclosed in the '358 patent exhibit a generally similar outer configuration to the mats of the present invention, the mats described in the '358 patent do not contain integral internal cellular structure. Moreover, the airfield mats of the '358 patent, unlike the preferred embodiment of the mats of the present invention, are not constructed of two mirror-image panels or half-mats which are joined together to form a complete single mat.
U.S. Pat. No. 5,653,551 to Seaux also describes a mat system for the construction of roadways and equipment support surfaces comprised of individual mats containing internal cellular structure. However, the mats disclosed in the '551 patent do not include traction promoting elements in the form of raised strips extending outward from the planar surfaces of the individual mats. More significantly, the '551 patent does not disclose the placement of such raised strips proximate to, and in general alignment with, the internal cell forming walls of the individual mats. In addition, the mats disclosed in the '551 patent contain offset peripheral edges, but lack means for mechanically affixing said mats to adjacent mats.
U.S. Pat. No. 5,888,612 to Needham, et al, discloses load bearing structures which can be molded from thermoplastic resin, and which have internal cellular structure. However, the individual mats described in the '612 patent have a dramatically different outer configuration than the mats of the present invention. Further, the mats described in the '612 patent also lack traction promoting elements on the outer planar surfaces of said mats, as well as means for mechanically joining said mats to other adjoining mats.
The prior art in general, and the aforementioned patents in particular, fail to disclose a mat system having the advantages of the invention disclosed herein.
SUMMARY OF THE INVENTION
The mat system of the present invention is a durable, reusable mat system which can be utilized to construct roadways and other support surfaces. Moreover, the mat system of the present invention can be horizontally expanded in all lateral and longitudinal directions to provide the desired coverage by the roadway or other support surface being constructed. Due to the generally uniform outward configuration of the individual mats of the present invention, a roadway and/or other support surface can be installed in a single layer by simple placement of the individual mats. Additionally, this generally uniform outward configuration allows for great flexibility in the installation process. These qualities greatly reduce the time, expense and labor requirements associated with installing and removing the disclosed invention.
The mat system of the present invention further comprises individual mats which are impermeable, so that fluids cannot seep through said mats. For this reason, the pumping effect observed with other conventional mats is effectively eliminated, and deterioration of the underlying terrain is thereby greatly reduced. The individual mats of the mat system of the present invention are also lighter than mats of most conventional mat systems, which allows for more efficient and economical transportation of said mats to and from installation locations.
Because the mats of the present invention possess substantially continuous outer surfaces, there are no gaps or channels in which mud and other contaminants can accumulate. Further, the mats of the present invention can be easily washed to remove any mud or other contaminants which may adhere to the outer surfaces of said mats. These qualities prevent the spread of contaminants from one installation location to another.
The dimensions of the individual mats of the present invention can be varied to fit particular uses and/or applications. In the preferred embodiment, the lateral dimensions of the individual mats of the present invention are approximately eight (8) feet wide by fourteen (14) feet long. Again, it must be stressed that these dimensions are not a limitation; the dimensions of the individual mats of the present invention can be changed as necessary to fit a particular application. As such, although it is generally beneficial for all individual mats of the mat system of the present invention to be roughly the same size as one another, it may be desirable to have a number of mats of different dimensions to customize the shape of a work surface or permit placement of mats where space may be limited.
Traction promoting elements are provided on the planar surfaces of the individual mats of the present invention. Said traction promoting elements are utilized to improve frictional characteristics of said mats, thereby improving traction for vehicles and other equipment traveling across roadways and other support surfaces constructed from the mat system of the present invention. Ideally, said traction promoting elements are raised members extending outward from the planar surfaces of the individual mats of the invention described herein. A large number of said raised members are beneficially positioned proximate to, and in general alignment with, the cell walls defining the internal cellular structure of said individual mats. In the preferred embodiment, wherein the cellular structure of the individual mats is in the shape of a plurality of hexagonal honeycombs, said traction promoting elements are corresponding in the form of raised strips extending outward from the planar surfaces of the individual mats of the present invention, and defining a plurality of generally star-like patterns on said planar surfaces.
When significant weight is placed on the individual mats of the present invention, such as when said mats are subjected to downward loading from trucks or other heavy equipment, said raised traction promoting elements are likewise subjected to heavy loading. Because said traction promoting elements represent substantially less surface area than the planar surfaces of said individual mats, such loading will tend to be focused or concentrated on said traction promoting elements. When such raised members are positioned proximate to, and in alignment with, the internal cell forming walls of the individual mats, said cell forming walls provide direct support for loading. However, when a large number of such raised members are not positioned in such a manner, the relatively thin outer skin defining the roughly planar surfaces of the mats can become easily deformed by such direct loading.
In addition to said traction promoting raised elements, the preferred embodiment of the mats of the present invention also include traction promoting anti-skid planar surfaces. Such anti-skid surfaces can be affixed to the mats or molded into said mats by overmolding a thin layer of traction promoting material on the work surface of said mats. In the preferred embodiment, said mats are molded primarily of thermoplastic resin. During the molding process, a relatively thin surface layer of low density material is overmolded across the bulk thermoplastic resin. Although any number of materials can be contemplated for this purposes, low density polyethylene (“LDPE”) or very low density polyethylene (“VLDPE”) can be used for this purpose in the preferred embodiment. Said low density material exhibits a greater coefficient of friction than the bulk resin used to mold the mats, which in turn promotes the anti-skid quality of said surface layer. Further, to the extent that said mats are molded out of thermoplastic resin, any number of additives can be included within the mats to meet or otherwise improve desired characteristics. For example, in the preferred embodiment, it may be beneficial to include one or more additives to control the static electricity characteristics of the mats.
In the preferred embodiment of the present invention, the individual mats are constructed of two mirror-image half-pieces which are joined together to form a complete single mat. Said half-pieces are comprised of at least one area of reduced material consisting of a planar skin having cell forming walls which extend outward in roughly perpendicular fashion from said planar skin and which define open faced cellular structure. Each of said half-pieces also have two adjacent edge areas without exposed cellular structure that exhibit characteristics similar to solid structure; that is, said adjacent edges have roughly continuous outer surfaces on all sides. In order to form a single mat, two mirror-image half-pieces are affixed together, such that the areas of said half-pieces which exhibit open-faced cellular structure are aligned with, and directly adjacent to, one another.
The half-pieces of the present invention can be affixed together by a variety of means. For example, said half-pieces can be welded or glued together to form a complete mat. Such welding can be performed across the opposing surfaces of the half-pieces, or along the peripheral seam between said half-pieces. Additionally, mechanical fasteners such as screws and nuts, or rivets, can be used to join said half-pieces to one another. Furthermore, various combinations of such joining methods can be employed to affix said half-pieces to one another. In the preferred embodiment, a combination of mechanical fasteners and peripheral welding is used to affix said mirror-image half-pieces to one another to form a single, complete mat.
Additionally, it is desirable to utilize a plurality of rigid inserts between the mirror-image half-pieces of the present invention. Such inserts are beneficially shaped to fit within corresponding opposing cells of two half-pieces which are joined together to form a complete mat. In the preferred embodiment, such inserts are generally hexagonal in shape to correspond to the hexagonal shaped open-faced cells of the half-pieces of the present invention.
When the mats of the present invention are used to construct a roadway or support surface, particularly in a remote location, it is not uncommon for said mats to be exposed to large temperature changes. Often, one planar surface of a mat will be exposed to direct sunlight, while the opposite planar surface will be face down and therefore obscured from such sunlight. As a result, although two half-pieces are permanently affixed to form a single complete mat, a temperature differential can nonetheless exist between such half-pieces. This temperature variance can result in a differential in shrinkage rates between said half-pieces which can, in turn, generate forces which cause said half-pieces to curl and/or pull apart from one another. Rigid inserts placed within opposing cells of two half-pieces will help to offset such forces. Such rigid inserts help keep the half-pieces aligned with one another, and help resist differential shrinkage. Further, such rigid inserts also can improve overall stiffness characteristics of said mats. In applications where greater stiffness is required, a greater number of rigid inserts can be used.
As trucks or other vehicles travel across roadways or other support surfaces constructed from the mat system disclosed herein, mats of conventional mat systems can have a tendency to pull or “walk apart” from one another. It is possible for such a roadway or other surface constructed of the mat system of the present invention to remain roughly intact and useable without means of linking said mats together. However, in the preferred embodiment, the peripheral edges of said mats contain receptacles for receiving fastening devices. Such fastening devices act to mechanically affix the mats together, and thereby prevent said mats from pulling away from one another after being installed at a remote location. Any number of different configurations of receptacles and/or fasteners can be utilized. However, in the preferred embodiment, said receptacles are spaced in a consistent manner. Along the long edge of each mat, said receptacles are spaced in a group of three near the center of said mat, while an additional receptacle is positioned near each end of said long edge. Two receptacles are also located along the short edge of each mat. Additionally, a receptacle is positioned near the corners of the mat between said long and short sides.
It is therefore an object of the present invention to provide a durable, reusable mat system which can be utilized to construct roadways or other support surfaces.
It is a further object of the present invention to provide a mat system wherein horizontal expansion of the desired roadway and/or equipment support surface is accommodated in all longitudinal and lateral directions.
It is a further object of the present invention to provide a mat system wherein the individual mats of said system are restrained from horizontal movement by frictional contact with the underlying terrain, and mechanical contact with adjoining mats.
It is a further object of the present invention to provide a mat system comprising a plurality of wholly interchangeable individual mats which can be installed in a single layer by simple relative placement.
Other and additional objects of the invention are apparent throughout the details of construction and operation as more fully described herein and illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a top plan view of a half-piece component of an individual mat of the present invention.
FIG. 2 depicts a cross-sectional cut-away view of a half-piece component along line 2 — 2 of FIG. 1 .
FIG. 3 depicts a top plan view of an individual mat of the present invention.
FIG. 4 depicts a side view of an individual mat of the present invention.
FIG. 5 depicts a cross-sectional cut-away view of an individual mat of the present invention along line 5 — 5 of FIG. 3 .
FIG. 6 depicts an exploded perspective view of two mirror-image half-pieces which together form a single mat of the present invention.
FIG. 7 depicts a perspective view of a single mat of the present invention.
FIG. 8 depicts a cut-away view of raised traction promoting elements along the planar surface of a single mat of the present invention.
FIG. 9 depicts a hexagonal insert positioned within a hexagonal honeycomb of a half-piece of the present invention.
FIG. 10 depicts a perspective view of a plurality of individual mats of present invention positioned to form a load supporting surface.
DESCRIPTION OF PREFERRED EMBODIMENT
In the preferred embodiment, the individual mats of the present invention are comprised of two mirror-image half-piece components which are affixed together to form a single mat. FIG. 1 depicts a half-piece component 10 of the present invention. In the preferred embodiment, an area of reduced material is in the form of open faced cellular structure, specifically a plurality of hexagonal honeycombs 12 . Such open faced cellular structure is generally comprised of interconnected cell forming walls 13 , which define said hexagonal honeycombs. In the preferred embodiment, said cell forming walls are integrally attached to a roughly continuous skin along one edge of said honeycombs, which in turn defines a generally planar work surface on one side of said half-piece. Two adjacent peripheral edges 14 and 15 of said half-piece 10 define areas having roughly continuous outer surfaces. Additionally, one or more recessed receptacles 16 are disposed through edges 14 and 15 . A plurality of holes 17 are disposed through half-piece 10 for receiving bolts or other fastening devices.
In the preferred embodiment, half-piece 10 is joined with and permanently affixed to a mirror-image half-piece. Said half-pieces are oriented such that the areas of reduced material, that is, cellular structure, on opposing half-pieces are aligned with one another such that only such sections of reduced material overlap. This orientation results in upper peripheral extensions along two adjacent edges of a complete mat of the present invention, and lower peripheral extensions along the remaining two sides of said complete mat.
Referring to FIG. 2, hexagonal honeycomb 12 is defined by vertical cell forming walls 13 . Roughly continuous skin 18 is integrally formed along the base of honeycomb 12 to define work surface 19 . Peripheral edge 14 has roughly continuous outer surfaces 14 a and 14 b , as well as chamfered edge 14 c . Recessed receptacle 16 is disposed through peripheral edge 14 . Recessed receptacle 16 has upper recessed ledge 16 a and lower recessed ledge 16 b.
Referring to FIG. 4, the preferred embodiment of the mat system of the present invention comprises a plurality of generally identical individual mats such as mat 20 . Mat 20 has upper stratum defined by upper half-piece 21 and a lower stratum defined by lower half-piece 22 , lower half-piece 22 being roughly identical to half-piece 10 depicted in FIG. 1 . Upper half-piece 21 and lower half-piece 22 of mat 20 are mirror images of one another. Upper half-piece 21 has generally planar upper work surface 23 , while lower half-piece 22 has generally planar lower work surface 24 . Upper half-piece 21 and lower half-piece 22 are mutually offset relative to each other, thereby resulting in upper peripheral extension 25 and lower peripheral extension 26 . In the preferred embodiment, peripheral edge 27 of upper half-piece 21 and peripheral edge 28 of lower half-piece 22 are chamfered along the full extent of said half-pieces. A plurality of raised traction promoting elements 23 a are disposed on generally planar upper work surface 23 , while a plurality of raised traction promoting elements 24 a are disposed on generally planar lower work surface 24 .
FIG. 3 depicts a top plan view of individual mat 20 , having upper half-piece 21 and lower half-piece 22 permanently affixed together, thereby defining upper peripheral extensions 25 a and 25 b on two adjacent edges of mat 20 , and lower peripheral extensions 26 a and 26 b on the remaining two adjacent edges of mat 20 . When two individual mats of the preferred embodiment are placed together laterally for purposes of constructing a roadway or other support surface, lower peripheral extension 26 a is received under upper peripheral extension 25 a of an adjacent mat; similarly, when two mats are placed together in longitudinal fashion, lower peripheral extension 26 b of one mat is received under upper peripheral extension 25 b of an adjacent mat.
Still referring to FIG. 3, a plurality of raised traction promoting elements 23 a are disposed on generally planar work surface 23 . In the preferred embodiment, said raised traction promoting elements are positioned proximate to and in general alignment with underlying cell forming walls. A plurality of holes 29 extend through mat 20 to receive bolts or other fastening devices to affix upper half-piece 21 to mirror image lower half-piece 22 . In the preferred embodiment, holes 29 have recessed ledges to permit said fastening means to be positioned below generally planar work surface 23 in order to avoid any obstruction to traffic utilizing said work surface. Further, a plurality of recessed receptacles 30 are disposed along peripheral edges. Chamfered edge 28 extends around lower half-piece 22 . Although obstructed from view in FIG. 4, chamfered edge 27 extends around upper half-piece 22 .
Referring to FIG. 5, which is a cross-sectional cut-away along line 5 — 5 of FIG. 3, upper half-piece 21 is affixed to lower half-piece 22 , thereby defining upper peripheral extension 25 . Upper half-piece 21 has chamfered edge 27 . Traction promoting raised elements 23 a are disposed on generally planar work surface 23 of upper half-piece 21 , while traction promoting raised elements 24 a are disposed on generally planar work surface 24 of lower half-piece 22 . Individual mat 20 has internal cellular structure defined by cells 42 , which are formed by cell forming walls 40 of upper half-piece 21 , being aligned with cells 52 , which are in turn formed by cell forming walls 50 of lower half-piece 22 . Roughly continuous skin 41 is integrally attached to the upper surface of cell forming walls 40 , while roughly continuous skin 51 is integrally attached to the lower surface of cell forming walls 50 . One surface of roughly continuous skin 41 defines generally planar work surface 23 of upper half-piece 21 , while the other surface of said roughly continuous skin 41 defines a closure for cells 42 . Similarly, one surface of roughly continuous skin 51 defines generally planar work surface 24 of lower half-piece 22 , while the other surface of roughly continuous skin 51 defines a closure for cells 52 . Recessed receptacle 30 having upper recessed ledge 30 a and lower recessed 30 b ledge extends through upper peripheral extension 25 .
FIG. 6 depicts an exploded perspective view of mat 20 of the present invention. Upper half-piece 21 and lower half-piece 22 are mirror images of one another, and are affixed together to form individual mat 20 . Area of open faced cellular structure of upper half-piece 21 is aligned with like area of open faced cellular structure of lower half-piece 22 . In the preferred embodiment, the open faced cellular structure of half-piece 21 is in the shape of hexagonal honeycombs which are formed by interconnected cell forming walls 40 , while the open faced cellular structure of half-piece 22 is in the shape of hexagonal honeycombs 52 which are formed by interconnected cell forming walls 50 . Bolts 70 pass through recessed holes 29 of mat 20 . Nuts 71 are screwed onto bolts 70 to join upper half-piece 21 to lower half-piece 22 .
Rigid inserts 60 are received within said internal cellular structure of mat 20 . In the preferred embodiment, rigid inserts 60 are in the shape of hexagonal inserts which are partially received within hexagonal honeycombs 42 of upper half-piece 21 and opposing hexagonal honeycombs 52 of lower half-piece 22 . FIG. 9 depicts rigid insert 60 received within a hexagonal honeycomb 52 of lower half-piece 22 of the present invention. Said rigid insert 60 extends above the upper surface of cell forming walls 50 of lower half-piece 22 , such that when a mirror image upper half-piece 21 is mated with and affixed to lower half-piece 22 , rigid insert 60 will also be partially received within hexagonal honeycomb 42 of upper half-piece 21 .
FIG. 7 depicts a perspective view of an individual mat 20 of the present invention, formed by joining mirror image upper half-piece 21 with lower half-piece 22 . Said half-pieces are affixed together with nuts 70 and bolts 71 which are received within holes 29 in mat 20 . Additionally, said half-pieces can be welded together. In the preferred embodiment, seam 80 between upper half-piece 21 and lower half-piece 22 is welded together on all four sides of mat 20 using extrusion welding.
FIG. 8 depicts a cut away view of upper half-piece 21 . Roughly continuous skin 41 is integrally attached to the upper surface of cell forming walls 40 , and defines generally planar work surface 23 . Traction promoting raised elements 23 a are disposed on generally planar work surface 23 . In the preferred embodiment, a plurality of said traction promoting raised elements 23 a are positioned proximate to and in general alignment with underlying cell forming walls 40 .
FIG. 10 depicts a plurality of individual mats 20 which are laid out to form a roughly continuous equipment support surface. When a plurality of individual mats are joined together, said mats form a roughly continuous and substantially smooth roadway or other support surface. Further, the overlap/underlap relationship shared by the offset peripheral edges of adjoining mats provides strength for load support purposes. Additionally, said overlap/underlap relationship also provides increased frictional contact between mats to help prevent separation of said mats.
In many applications, frictional contact alone is sufficient to keep said individual mats in contact with one another so that gaps will not develop between said mats. However, in the preferred embodiment, a plurality of recessed slots are provided along the peripheral edges of said mats. Said recessed slots are positioned in such a manner that, when individual mats of the present invention are laid out to form a roadway or support surface, recessed slots of adjoining mats are aligned with one another. Stakes can be disposed within said slots and, if desired, driven into the underlying terrain to further anchor said mats in position. Pegs 90 or other clamping means can be inserted into said slots and used to hold the mats in place. Said slots are recessed to ensure that a stake or other clamping means, when disposed within said slots, remain recessed below the generally planar upper work surface of said mats so as not to impede or provide a hazard for traffic using a roadway or equipment support surface constructed from the mat system of the present invention.
While the mat system of the present invention can be constructed of any number of materials, in the preferred embodiment the mats disclosed herein are constructed of synthetic materials. Said composite materials could include virgin thermoplastic resins, as well as re-claimed polyolefins and/or vulcanized rubber, as well as any number of additives which can improve or modify the characteristics of said mats. For example, such additives could improve the frictional quality of the mats or the ability of the mats to dissipate static electricity.
Whereas the invention is herein described with respect to a preferred embodiment, it should be realized that various changes may be made without departing from essential contributions to the art made by the teachings hereof. | A reusable mat system for the construction of load bearing surfaces, such as temporary roadways and equipment support surfaces, over unstable or unsubstantial terrain, comprising durable, interlocking individual mats which can be quickly and easily installed in a single application, and which can thereafter be easily removed and stored until needed again. The individual mats of the present invention interlock on all sides to form stable and continuous load bearing surfaces, and exhibit favorable traction characteristics. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a divisional of U.S. application Ser. No. 09/878,802 entitled AQUEOUS SUSPENSIONS OF PENTABROMOBENZYL ACRYLATE, filed Jun. 11, 2001 now U.S. Pat. No. 6,872,332, which claims foreign priority on Israeli Application No. 136725, filed on Jun. 12, 2000, the disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to novel compositions of matter that are aqueous suspensions of pentabromobenzyl acrylate (PBBMA) and to a process for making them.
BACKGROUND OF THE INVENTION
Pentabromobenzyl acrylate (PBBMA) is an acrylic monomer, which is useful in many applications, especially but not exclusively, in the field of fire retardants for plastic compositions. It can be polymerized easily by known techniques such as bulk polymerization, solution polymerization etc., or by mechanical compounding or extrusion. In mechanical compounding or extrusion, it may be grafted onto existing polymer backbones, or added to unsaturated loci on polymers.
All these properties render PBBMA a particularly useful tool in the hands of experienced compounders. However, it has been impossible, so far, to carry out aqueous manipulations with PBBMA, in spite of their desirability, because, on the one hand, PBBMA is insoluble in water, and on the other hand, because of its high bromine content, it has a high specific gravity, about 2.7, — and therefore does not lend itself to the preparation and use of aqueous suspensions.
It is a purpose of this invention to provide stable dispersions or suspensions of PBBMA, which are new compositions of matter. Dispersions and suspensions are to be considered synonyms, as used herein.
It is another purpose of this invention to provide such dispersions or suspensions that are aqueous dispersions or suspensions.
It is a further purpose of this invention to provide a process for preparing such suspensions.
It is a further purpose of this invention to provide suspensions of PBBMA for particular applications in industry.
It is a still further purpose of this invention to provide suspensions of PBBMA together with additional compounds, such as synergists for increasing the fire-retarding efficiency of compositions obtained from PBBMA.
It is a still further purpose of this invention to provide processes comprising the polymerization and/or copolymerization of PBBMA for the production of particular products.
Other purposes and advantages of the invention will appear as the description proceeds.
SUMMARY OF THE INVENTION
The suspension of PBBMA, according to the invention, is characterized in that it comprises PBBMA in the form of finely ground particles, having a size smaller than 50 μm and preferably smaller than 10 μm and more preferably from 0.3 μm to 10 μm, and contains suspending agents chosen from among xanthene gums, anionic or nonionic purified, sodium modified montmorilonite, naphthalene sulfonic acid-formaldehyde condensate sodium salt, sodium or calcium or ammonium salts of sulfonated lignin, acrylic acids/acrylic acids ester copolymer neutralized-sodium polycarboxyl, and wetting agents chosen from among alkyl ether, alkylaryl ether, fatty acid diester and sorbitan monoester types, polyoxyethylene (POE) compounds. The POE compounds are preferably chosen from among:
POE allyl ethers N-5; 10; 20;
POE lauryl ethers N-5; 10; 20;
POE acetylphenyl ethers N-3; 5; 10; 20;
POE nonylphenyl ethers N-3; 4; 5; 6; 7; 10; 12; 15; 20;
POE dinonylphenyl ethers N-5; 10; 20;
POE oleate-N-9, 18, 36;
Sorbitan monooleate N-3; 5; 10; 20.
Alkyl naphthalene sulfonates or their sodium salts.
N is the number of ethylene oxide units.
Said suspension is typically, though not necessarily, an aqueous one.
The suspension according to the invention may also include nonionic or anionic surface active agents or wetting agents, which can be chosen by persons skilled in the art. For example, nonionic agents may be polyoxyethylene (POE) alkyl ether type, preferably NP-6 (Nonylphenol ethoxylate, 6 ethyleneoxide units) Anionic agents may be free acids or organic phosphate esters or the dioctyl ester of sodium sulfosuccinic acid. It may, also, include other additives which function both as dispersing agents and suspending agents commonly used by skilled persons like sodium or calcium or ammonium salts of sulfonated lignin, acrylic acids/acrylic acids ester copolymer neutralized-sodium polycarboxyl, preferably naphthalene sulfonic acid-formaldehyde condensate sodium salt. The suspension according to the invention may also include defoaming or antifoaming agents, which can be chosen by persons skilled in the art. For example, emulsion of mineral oils or emulsion of natural oils or preferably emulsion of silicon oils like AF-52™.
The invention further comprises a method of preparing a suspension of PBBMA, which comprises grinding the PBBMA together with wetting agent and preferably also dispersing agent to the desired particle size adding it to the suspending medium, consisting of water containing suspension stabilizing agents, with slow stirring, preferably at 40 to 400 rpm. Grinding is preferably carried out with simultaneous cooling. The order of the addition of the wetting agents, the dispersing agents and the suspending agents is important.
Preserving or stabilizing agents such as Formaldehyde, and preferably a mixture of methyl and propyl hydroxy benzoates, can also be added to the suspension.
Typical size distributions of PBBMA both before grinding and as they are when present in suspensions according to the invention, are listed hereinafter. “D” indicates the diameter of the particles in μm and S.A. indicates the surface area in square meters per gram. “v” designates volume and 0.25 means 25% by volume.
D (v, 0.1)
D (v, 0.5)
D (v, 0.9)
Specific S.A.
PBBMA before
2.40
19.34
58.20
0.3623
grinding
PBBMA in
0.36
1.54
6.62
2.2554
suspension
In an embodiment of the process of the invention, wherein suspensions of PBBMA and additional compounds—such as fire-retardant synergists, e.g. fire-retardant antimony oxide (AO), the process comprises preparing a suspension of the additional compound in a way similar to the preparation of the PBBMA suspension, and then mixing the two suspensions, preferably by adding the suspension of the additional compound to a slowly stirred suspension of PBBMA, and continuing stirring until a homogeneous, mixed suspension is obtained.
The suspensions, in particular the aqueous suspensions, of the invention are stable. When stored at room temperature, they are stable for at least two weeks and preferably at least one month. Their stability may be higher, e.g. three months or more. If they have to be stored at high temperature, they should pass the “Tropical Storage Test”, at 54° C., viz. be stable under such Test for at least one week.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The following examples are intended to illustrate the invention, but are not binding or limitative.
EXAMPLE 1
Preparation of a Suspension of PBBMA
A glass bead wet mill equipped with cooling jacket and continuous feed by a peristaltic pump, was utilized for grinding. PBBMA (750 gr) was mixed with water (240 ml), NP-6 (Nonylphenol ethoxylate) (1 ml) and Darvan#1 (Naphtalenesulfonic acid formaldehyde condensate, sodium salt) (30 gr). The mixture was fed into the grinding beads mill over a period of 25 min. The resulting slurry was stirred gently, mechanical blade stirrer, 40-60 rpm, and 10 ml of 1.5% Rhodopol 23, Xanthan Gum (CAS No 11138-66-2) in water with preserving agents, 1% Methyl Paraben, methyl-4-hydroxybenzoate, CAS No 99-76-3 and 0.5% Propyl Paraben, propyl-4-hydroxybenzoate, CAS No 94-13-3, were added.
EXAMPLE 2
Preparation of a PBBMA-AO Suspension
A suspension of Antimony Oxide was prepared as follows. To a 3-liter round bottom flask, fitted with a mechanical stirrer, were added water (240 ml), NP-6 (1 ml) (Nonylphenol ethoxylate), and Darvan #1 (Naphtalenesulfonic acid formaldehyde condensate, sodium salt) (30 g). Finely ground antimony oxide, Ultrafine grade with typical average particle size of 0.2 μm-0.4 μm. (AO, 750 g) was slowly added under fast stirring, 400-600 rpm. The stirrer was slowed, 50-150 rpm and a 1.5% solution of Rhodopol 23 Xanthan Gum (CAS No 11138-66-2) with preserving agents—1% Methyl Paraben, methyl-4-hydroxybenzoate, (CAS No 99-76-3) and 0.5% Propyl Paraben, propyl-4-hydroxybenzoate, (CAS No 94-13-3) were added (115 ml).
The mixed PBBMA-AO suspension was prepared as follows. To a slowly stirred, 40 rpm, suspension of PBBMA (750 ml) at 25° C.-30° C., obtained as described in Example 1, was added the AO suspension (250 ml) as described above. After five minutes, stirring was stopped, yielding a homogeneous mixture.
EXAMPLE 3
Preparation of a PBBMA-Styrene-Butylacrylate Terpolymer Latex
In a 0.5 L 4 necked round bottom flask fitted with mechanical stirrer, reflux condenser, thermometer, dropping funnel and Nitrogen inlet were charged 1.4 gr SDS (Sodium Dodecyl Sulfate) and 100 mL of water. The flask was immersed in an oil bath and heated to 70° C. with continuous stirring, 250 rpm, Nitrogen was introduced under the surface of the liquid. After 1 hr. the nitrogen inlet was raised above the surface of the liquid and 0.15 gr of K 2 S 2 O 8 were added. Five minutes later a solution of 15 gr Styrene and 15 gr Butylacrylate was added dropwise over 30 min. The emulsion pre-polymerization was continued for another 90 min. after which 6 gr of a PBBMA suspension (˜60% solids) were added dropwise over 70 min. The polymerization was continued overnight.
A stable latex (stable for more than two month) was obtained.
The terpolymer isolated from this emulsion was characterized. The bromine content was 7% and the glass transition temperature was 18.8° C.
EXAMPLE 4
Preparation of a PBBMA-Styrene-Acrylonitrile Terpolymer
In a 0.5 L 4 necked round bottom flask fitted with mechanical stirrer, reflux condenser, thermometer, dropping funnel and Nitrogen inlet were charged 1.4 gr SDS (Sodium Dodecyl Sulfate) and 100 mL of water. The flask was immersed in an oil bath and heated to 70° C. with continous stirring, 250 rpm, Nitrogen was introduced under the surface of the liquid. After 1 hr. the nitrogen inlet was raised above the surface of the liquid and 0.15 gr of K 2 S 2 O 8 were added. Five minutes later a solution of 18.2 gr Styrene and 5.8 gr Acylonitrile was added dropwise over 30 min. The emulsion pre-polymerization was continued for another 20 min. after which 8.5 gr of a PBBMA suspension (˜60% solids) were added dropwise over 40 min. A second portion of 0.15 gr of K 2 S 2 O 8 was added 3 hr. after the addition of the suspension was finished. The polymerization was continued overnight.
A stable latex (stable for at least one month) was obtained.
The terpolymer isolated from this emulsion was characterized. The bromine content was 12.5%, the nitrogen content was 5% and the glass transition temperature was 107° C. The molecular weight depends on the polymerization conditions. In this particular case a Weight Average Molecular Weight, Mw, of 1.2*10 6 and Number Average Molecular Weight, Mn, of 422,000, was determined (in Dimethylformamide solution, calibrated with Polystyrene standards).
The suspensions of the invention are useful for a number of applications, and the way in which they are used and the resulting products, are also part of the invention.
Fire Retardants are commonly used in carpet-backings. However, the fire retardants of the prior art are not bound to the carpet, and are susceptible to removal by dry cleaning. According to the invention, the aqueous suspension of PBBMA is applied to the reverse side of the carpets and is polymerized by heating at temperatures above 130° C. This results in a coating of PBBMA polymer, which is bound to the carpet.
In the prior art, fire retardants are used in the textile industry. However, they generally produce light scattering, because they are used in powder form. According to the invention, the aqueous solution of PBBMA, optionally with complementary components, is applied to textile materials and penetrates into the fibers, and then polymerization is effected by heating at temperatures above 130° C., thus polymerizing PBBMA and binding the resulting polymers to the fibers. Addition of free radical initiating catalysts, the conventional polymerization catalysts such as organic peroxides, e.g., benzoylperoxide, or other free radical producing catalysts, e.g., azobisisobutyronitrile, will shorten polymerization time.
The PBBMA suspensions of the invention can be used to copolymerize PBBMA with other monomers or grafted to polymers, in order to produce adhesives, which are also fire-retardants or other types of surface modifiers and binding promoters.
Likewise, the suspensions of the invention can be used to copolymerize PBBMA with other (meth)acrylate derivatives, such as butyl acrylate, methyl methacrylate or other monomers, to produce transparent plastics of predetermined refraction indices.
Double layered particles can also be produced, according to the invention, by adding another monomer, e.g. another (meth)acrylic derivative, to the PBBMA suspensions under polymerization conditions, to produce very stable latexes. An example of such other monomers can be, for instance, aliphatic (meth)acrylates or hydroxyethyl acrylate.
The novel products obtained according to the invention, and the processes for their production, are also part of the invention.
While examples of the invention have been described for purposes of illustration, it will be apparent that many modifications, variations and adaptations can be carried out by persons skilled in the art, without exceeding the scope of the claims. | Suspensions of PBBMA, characterized in that they comprise PBBMA in the form of finely ground particles and contain suspending agents chosen from among xanthene gums, anionic or nonionic purified, sodium modified montmorilonite, naphthalene sulfonic acid-formaldehyde condensate sodium salt, sodium or calcium or ammonium salts of sulfonated lignin, acrylic acids/acrylic acids ester copolymer neutralized-sodium polycarboxyl, and wetting agents chosen from among alkyl ether, alkylaryl ether, fatty acid diester and sorbitan monoester types, polyoxyethylene (POE) compounds. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims benefit, under 35 U.S.C. §119(e), of U.S. Provisional Application Ser. No. 61/024,009, filed 28 Jan. 2008, the entire contents and substance of which are hereby incorporated by reference.
BACKGROUND
[0002] Embodiments of the present invention relate to a light string system and, more particularly, a light emitting diode (LED) light string system.
[0003] Conventional light strings are known in the art. Conventional light strings are predominantly used during the holiday season for decorative purposes, e.g., Christmas tree lights, outdoor holiday lights, and icicles light sets. Conventional light strings commonly comprise a plurality of light systems that include conventional light sources, i.e., preferably incandescent light bulbs having filaments.
[0004] A rather recent development in the design of conventional light strings is to include light emitting diodes as a light source. Advantages of light emitting diodes over incandescent light bulbs include, but are not limited to, lower power consumption, longer lifespan, lower heat generation, smaller size and weight, robustness, faster switching time, and being available in a number of colors.
SUMMARY
[0005] Briefly described, embodiments of the present invention include a light emitting diode (LED) light string system. The LED light string system has the look of the conventional incandescent light string systems, but illuminates via light emitting diodes instead.
[0006] In an exemplary embodiment, a lamp system for a light string system including a plurality of lamp systems. Each lamp system comprises a light assembly, a socket assembly, and a refractive assembly. The light assembly includes a light emitting diode. The socket assembly includes a socket dimensioned to receive via insertion a portion of the light assembly. Further, the socket assembly includes a pair of contacting members on opposing sides of the socket. The refractive assembly covers a majority of the light assembly enabling refraction of an illuminated light assembly.
[0007] These and other objects, features, and advantages of the present invention will become more apparent upon reading the following specification in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates a partial cross-sectional view of a lamp system for use in a light emitting diode (LED) light string system, in accordance with an exemplary embodiment of the present invention.
[0009] FIG. 2 illustrates a partial cross-sectional view of a light assembly illustrating exemplary refraction and reflection of an illuminated light emitting diode, in accordance with exemplary embodiments of the present invention.
DETAILED DESCRIPTION
[0010] To facilitate an understanding of the principles and features of embodiments of the invention, they are explained hereinafter with reference to implementations in illustrative embodiments. In particular, embodiments of the invention are described in the context of being a light emitting diode light string system.
[0011] Embodiments of the invention, however, are not solely limited to use as a light emitting diode light system. Rather, embodiments of the invention can be used wherever a circuit or other system with an illuminating characteristic is needed or desired.
[0012] The material described hereinafter as making up the various elements of the present invention are intended to be illustrative and not restrictive. Many suitable materials that would perform the same or a similar function as the materials described herein are intended to be embraced within the scope of the invention. Such other materials not described herein can include, but are not limited to, materials that are developed after the time of the development of the invention, for example.
[0013] Referring now in detail to the figures, FIG. 1 is a partial cross-sectional view of an exemplary embodiment of a lamp system for use in a light emitting diode (LED) light string system. The LED light string system comprises a plurality of lamp systems 100 connected to one another, in either parallel or series, wherein each lamp system 100 comprises a light assembly 200 , a socket assembly 300 , and a refractive assembly 400 . Each light assembly 200 comprises an LED 210 and a base 220 in communication with the LED 210 . Each socket assembly 300 comprises a socket 310 adapted to receive a portion of the light assembly 200 . Each refractive assembly 400 can partially or fully encapsulate the light assembly 200 including the LED 210 to provide brilliant refraction of an illuminated light.
[0014] The light assembly 200 of the lamp system 100 comprises the LED 210 and the base 220 in communication therewith. The LED 210 is adapted to illuminate when energized. In an exemplary embodiment, conductors can be in electrical communication with the LED 210 . The conductors enable energy to the LED 210 for illumination purposes. The conductors of the LED 210 can extend down through the base 220 , wherein exemplarily the conductors can be in communication with a pair of lead wires 222 external the base 220 . In one embodiment, the conductors and the lead wires 222 can be the same wire/conductor. The lead wires 222 extend through a bottom of the base 220 , and are a pair of wires that can be wrapped around the base 220 extending upwardly in the direction of the LED 210 , adjacent the base 220 .
[0015] The light assembly 200 further includes the base 220 . The base 220 can be integrally formed with the LED 210 . The base 220 can be a unitary element of the LED 210 , or a separate element. Exemplarily, the base 220 communicates between the LED 210 and an associated socket 310 , complimenting and facilitating the seating of the light assembly 200 to the socket 310 .
[0016] In an exemplary embodiment, the base 220 can incorporate at least one ridge 226 to ensure a snug fit with the socket 310 , preventing the accidental disengagement of the light assembly 200 from the socket assembly 300 . Other mechanical mechanisms can be used with the base 220 and the socket assembly 300 to ensure a tight fit.
[0017] Each socket can include contacting members 320 on opposing sides for interacting and being in electrical communication between the wires 222 of the LED 210 and the wires 314 between the lamp systems 100 .
[0018] In an exemplary embodiment, the light assembly 200 can further comprise a locking assembly 330 to secure the light assembly 200 to the socket assembly 300 . The locking assembly 330 may be exterior, or designed within the socket assembly 300 to fasten and/or couple the connection of the light assembly 200 to the socket assembly 300 internally. In an exemplary embodiment, the locking assembly 330 is external and can include cooperating light assembly elements 224 and socket assembly element 304 . These elements 224 and 304 can be formed as a clasp and a lock to insert the clasp. For example, the base 220 of the light assembly 200 can include the element 224 that extends approximately normal to the base 220 and can define an aperture. On the other end of the locking assembly 330 can be the element 304 , which extends outwardly from the socket 310 , and can be inserted into the element 224 of the base 220 . As the element 304 of the socket 310 is inserted into the element 224 of the base 220 , the locking assembly is complete. In another example, the clasp can be coupled to the base 220 of the light assembly 200 and the receiving portion can be coupled to the socket 310 ; as a result, the element 304 can define the aperture to receive the element 224 .
[0019] Stringent Underwriters Laboratories (UL) requirements recently require that lights and sockets fit tightly together; this requirement may ultimately decrease the value of the locking assembly 330 in the lamp system 100 . Advantageously, the improvement in injection molding machines now enables the production of sockets and lamp assemblies that have a tight, snug fit.
[0020] Wires 314 connect lamp system 100 to one another, in either electrical series or electrical parallel relationship. The lead wires 222 of the light assembly 200 are in electrical communication with the wires 314 , such that power flowing through the wires 314 can be transferred to the lead wires 222 and thus activate the LED 210 . For example, one of the lead wires 222 is in communication with one of the contacting member 320 , which is in communication with the wire 314 ; the same can be true for the opposing lead wire 222 .
[0021] Light strings, such as the decorative light string system disclosed herein, are typically arranged with lamp systems 100 being electrically connected in series, rather than in a parallel arrangement. Unfortunately, there are disadvantages to designing a light string in series. When even a single light assembly is removed from a socket assembly, the entire series of lights is rendered inoperable. Because each light assembly within its respective socket completes the electrical circuit, when a light assembly is removed or the filament of the bulb burns out, a gap is created in the circuit; that is, an open circuit is formed. Thus, electricity is unable to continue to flow through the circuit.
[0022] To overcome this dilemma, in an exemplary embodiment, the socket assembly 300 can include a shunting device 350 to enable the energy flowing through the light string system to continue to flow even when a light assembly 200 is absent from the socket 310 . For example and not limitation, the light string will remain illuminated even though there may exist: for example, a faulty light emitting diode, faulty socket, or simply because the LED is not properly mounted in its respective socket, or is entirely removed or falls out of its respective socket. For instance, the bypass activating system described in Massabki et al., U.S. Ser. No. 11/849,423, filed Sep. 4, 2007, the entire disclosure of which is incorporated herein by reference, can be used as the shunting device 350 herein.
[0023] The refractive assembly 400 can include a refraction layer 405 to protect the LED 210 of the light assembly 200 . In an exemplary embodiment, the refraction layer 405 can be a globe 410 for covering most, if not all, of the LED 210 . The globe 410 is in communication with, and terminates at the base 220 . The globe 410 comprises an open bottom end 412 , such that the open bottom end 412 is in communication with a top portion of the base 220 , and a closed top end 414 . The open bottom end 412 can receive and encapsulate a portion of the LED 210 . As a result, the LED 210 is protected from harsh elements, including inclement weather (e.g., water) and other debris.
[0024] The globe 410 can be made of conventional translucent or transparent material such as plastic, glass, and the like. The globe 410 defines a hollow interior enabling protection of and receiving the LED 210 . Unlike other LED light string systems, the globe 410 provides the look of conventional incandescent light systems. Further, unlike conventional incandescent-based light strings, if the globe 410 were to break, the LED 210 will remain illuminated and protected.
[0025] The globe 410 can be either removably attached to the base of the light assembly or alternatively permanently attached. The globe 410 can be provide protection the LED 210 , such that the LED 210 and the interior of the base 220 and the socket 310 are further protected from its elements, including being waterproof.
[0026] In addition, the globe 410 can refract or change the direction of light emitting from an illuminated LED 210 . Unlike conventional LEDs, which illuminate more like a spotlight and fail to illuminate light in a large direction, the globe 410 enables the LED 210 to appear and thus illuminate as a conventional light source having a filament. For example and not limitation, by incorporated the globe 410 , the LED 210 can now shine up to 270 degrees, rather than in a single directed direction.
[0027] Exemplarily, as shown in FIG. 2 , when the globe 410 covers an illuminated LED 210 , light from the LED 210 not only illuminates upwardly, but also partially about the sides 415 of the globe 410 . The closed top end 414 of the globe 410 not only refracts the light, but also reflects the light to back within the hollow cavity, as illustrated by the exemplary light paths shown in FIG. 2 . Likewise, the sides 415 of the globe 410 can also reflect the light about and within the hollow cavity.
[0028] While the invention has been disclosed in its exemplary forms, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made therein without departing from the spirit and scope of the invention and its equivalents, as set forth in the following claims. | The light emitting diode (LED) light string system includes a plurality of lamp systems. Each lamp system includes a single LED, a base, and a globe to cover the LED. The LED light string system appears similar to the conventional incandescent light string system, but instead illuminates via LEDs. Each LED is covered by the globe similar to those available in incandescent systems, which provides refraction of the illuminated LED to produce an LED light string that has the look of a conventional incandescent light string. | 5 |
FIELD OF THE INVENTION
This invention relates to a bobbin supply system for spinning frames for supplying a predetermined bobbin precisely to a predetermined spinning frame in accordance with a type of a yarn to be set on the spinning frame when a bobbin frame which a yarn has been unwound by a winder is to be returned to the spinning frame side.
BACKGROUND OF THE INVENTION
In a spinning mill, bobbins of cops unwound by a winder are normally returned to the spinning frame side in order to use them again. To this end, various bobbin supply systems have been proposed and put into practical use. Further, it is a very popular means to differentiate bobbins to be supplied to spinning frames from each other in accordance with types of yarns to be set on the spinning frames, for example, to differentiate such bobbins in color, to facilitate discrimination of types of yarns of cops for a next step.
In this manner, it is necessary for a bobbin supply system to supply a predetermined bobbin precisely to a predetermined spinning frame, and a simplest one of conventional bobbin supply systems for realizing such function is constituted such that, for example, a pair of bobbin supply devices B1 and B2 and a plurality of spinning frames S1, S2, . . . , Sm are communicated with each other by way of a single transport passage C (FIG. 5). Here, each of the bobbin supply devices B1 and B2 is constituted such that it forwards a bobbin of a predetermined type into the transport passage C in response to a bobbin requesting signal from a predetermined spinning frame S1 (i=1, 2, . . . , m). Such bobbin requesting signal includes information representative of the spinning frame Si and information which specifies a type of a bobbin requested. It is to be noted that a bobbin change-over mechanism not shown which operates in response to a bobbin requesting signal is incorporated at each of branch points at which the transport passage C branches to the individual spinning frame Si. Thus, a bobbin transported from the upstream side of the transport passage C can be sent into a predetermined spinning frame Si by means of the corresponding change-over mechanism.
Further, m spinning frames S1, S2, . . . , Sm may be divided into two groups individually including k spinning frames and m-k simming frames, and a transport passage C and a pair of bobbin supply devices B1 and B2 may be provided similarly as in the system shown in FIG. 5 for each of the groups (FIG. 6). Such arrangement is advantageous in that the availability factor of the entire spinning frames can be improved because a bobbin supplying operation can be performed simultaneously to two spinning frames Si and Sj (1≦i≦k, k+1≦j≦m) which belong to the different groups from each other.
The prior art, however, has a problem that it cannot always be adapted precisely for a demand for lot production of many articles by small quantities which is conducted commonly in recent spinning mills. In particular, since normally the doffing period is different depending upon a type of yarn to be set on a spinning frame, in case various types of yarns are handled in the prior art arrangement shown in FIG. 5, there is the possibility that such an opportunity that a spinning frame having a comparatively short doffing period is rendered inoperative for a bobbin supplying operation for another spinning frame having a comparatively long doffing period may be increased, which will significantly deteriorate the overall availability factor.
On the other hand, while the overall availability factor can be improved as compared with the prior art arrangement shown in FIG. 5 if yarns of the same type are worked on spinning frames which belong to the same group, there is a problem that, since the number of spinning frames involved in each group is fixed, the arrangement cannot cope effectively with a variation in number of production lots of each yarn type.
OBJECT OF THE INVENTION
The present invention has been made in view of such circumstances as described above, and it is an object of the present invention to provide a bobbin supply system for spinning frames wherein the numbers of spinning frames on which yarns of different types are to be set can be changed at any time in accordance with a variation in number of production lots of yarns of different types and predetermined bobbins conforming to the yarn types to be set on the individual spinning frames can be supplied appropriately with certainty so that a plurality of types of yarns can be produced simultaneously by appropriate lot numbers without deteriorating the availability factor of the spinning frames.
SUMMARY OF THE INVENTION
In order to attain the object, according to the present invention, a bobbin supply system is constituted such that said spinning frames are divided into a plurality of dedicated machine groups each for working yarns of a fixed type and a common machine group disposed between each adjacent ones of said dedicated machine groups for working yarns of a selected one or ones of different types, and that said system comprises a main transport path capable of supplying bobbins to all of said dedicated machine groups and the common machine group or groups from the upstream side toward the downstream side, a sub transfer path joined to said main transport path at a boundary position between each of the common machine group or groups and an adjacent one of said dedicated machine groups on the downstream side of the common machine group for supplying bobbins to the spinning frames on the downstream side of the position, and a communicating transport path provided for each of the spinning frames of the common machine group or machine groups adjacent the boundary position or positions for establishing communication between said sub transport path and said main transport path.
With the bobbin supply system, bobbins are supplied by way of the main transport path at least to the spinning frames which belong to the most upstream side one of the dedicated machine groups while bobbins are supplied to the spinning frames which belong to any other dedicated machine groups by way of the sub transport path or main transport path corresponding to the dedicated machine group. On the other hand, bobbins can be supplied to the spinning frames which belong to any one of the common machine group or groups by way of the same route to that for an adjacent one of the dedicated machine groups on the upstream side of the common machine group. In this manner, the spinning frames which belong to each of the dedicated machine groups and the spinning frames which belong to an adjacent one of the common machine group or groups on the downstream side of the dedicated machine group form a group, and yarns of a same type are set for each group in operation.
When the numbers of the spinning frames which belong to the individual groups are to be changed, the communicating transport paths are used. In particular, when a certain one or ones of the spinning frames which belong to a common machine group are separated from an adjacent one of the dedicated machine groups on the upstream side and then combined with the spinning frames which belong to another adjacent one of the dedicated machine groups on the downstream side so as to form a new group, the communicating transport path corresponding to the most upstream side one of the certain spinning frame or frames is used to change to the position at which the communicating path is communicated with the main transport path. Consequently, the number of spinning frames which belong to each group can be changed by changing separation of the spinning frames of a common machine group.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic representation of an entire bobbin supply system showing an embodiment of the present invention;
FIG. 2 is a diagrammatic representation showing details of part of the system shown in FIG. 1;
FIG. 3 is a diagrammatic representation schematically showing another embodiment of the present invention;
FIG. 4 is a similar view but showing a further embodiment of the present invention; and
FIGS. 5 and 6 are similar views but showing exemplary ones of conventional yarn supply systems.
DETAILED DESCRIPTION OF THE INVENTION
In the following, different embodiments of the present invention will be described with reference to the drawings.
Referring to FIG. 1, a bobbin supply system for spinning frames includes, in combination, bobbin reservoirs Rj (j=1, 2, . . . , n) interposed between spinning frames Si (i=1, 2, . . . , m) arranged in a row and winders Wj (j=1, 2, . . . , n) and corresponding to the winders Wj, and a bobbin transport conveyor 70. It is to be noted that a cop transport system from the spinning frames Si to the winders Wj is also shown in FIG. 1.
The cop transport system is constituted such that it accommodates cops wound up on the spinning frames Si into predetermined cop magazines and transports them to the winders Wj by way of a cop transport conveyor system 10 which includes a forward conveyor 11, a working device line 12 which forms a bypass to the forward conveyor 11, a stock line 13, a communicating conveyor 14 which forms an exit passage from the stock line 13, and branch conveyors 15 which branch from the communicating conveyor 14 to the individual winders Wj.
A cop boxing device 62 is disposed on the out end side of the spinning frames Si and adapted to move back and forth by itself on a guide rail 61. The cop boxing device 62 is constituted such that it can stop on the out end side of a predetermined spinning frame Si and accommodates cops doffed from the spinning frame Si in an orderly fashion into a cop magazine, and then transport the cop magazine to a home position 62h provided on the guide rail 61.
The cop boxing device 62 can, at the home position 62h thereof, discharge the cop magazine (hereinafter referred to only as magazine), in which the cops are accommodated, onto a turntable 63a which forms a starting end portion of the cop transport conveyor system 10. Meanwhile, another turntable 63b is provided at a last end of an empty magazine conveyor system 40 which is disposed in such a manner as to reach the home position 62h, and the cop boxing device 62 can carry thereon an empty cop magazine (hereinafter referred to only as empty magazine) which has come to the turntable 63b, thereby to make preparations for an accommodating operation for cops from another spinning frame Si.
The working device line 12 branches from the forward conveyor 11 at a branching point 12a and, passing a plurality of standby lines 12b and a working device 12c which performs a setting process of a cop, for example, by steam, joins the forward conveyor 11 at a joining point 12d. The working device 12c can make batch processing of a plurality of occupied magazines while each of the standby lines 12b can store in a row thereon at least a number of occupied magazines corresponding to one batch of the working device 12c. A branch point 12e and a joining point 12f are formed on the upstream side and the downstream side, respectively, of each of the standby lines 12b.
On the other hand, the stock line 13 includes a plurality of rows of conveyors 13a each having a branch point 13b and a joining point 13c on the upstream side and the downstream side thereof, respectively. Each of the stock conveyors 13a can store thereon, for example, a number of occupied magazines sufficient to absorb a difference in working capacity between the spinning frames Si which operate continuously day and night and the winders Wj which operate only in the daytime.
The branch conveyors 15 branch from the communicating conveyor 14 individually by way of branch points 15a. A cop feed device 15b is disposed intermediately of each of the branch conveyors 15 and operates to discharge cops from an occupied magazine transported thereto and forward only a cop into a winder Wj in response to a cop requesting signal from the winder Wj. In particular, on each of the branch conveyors 15, an occupied magazine is transported to the cop feed device 15b, but only cops are transported from the cop feed device 15b to the winder Wj. Yarn end pickup devices Wja (j=1, 2, . . . , n) for picking up an end of a yarn of a cop are disposed at entrance ends of the winders Wj.
Empty magazines discharged from the cop feed devices 15b are fed back to the home position 62h by way of the empty magazine conveyor system 40 which includes a connecting conveyor 41, an empty magazine stock line 42 and a return conveyor 43. The empty magazines are thus used again by means of the cop boxing device 62.
A tab setter 20 is disposed in or adjacent the home position 62h of the cop boxing device 62 which makes the starting point of the cop transport conveyor system 10. The tab setter 20 is provided to set and store a code (hereinafter referred to as tab code) indicative of a type of code accommodated in a cop magazine into a tab device provided on the cop magazine. Such tab code setting and storing means may be any one of, for example, mechanical, electronic, magnetic or some other means.
A tab reader 30 is disposed on the upstream side of each of the branch points 12a, 12e, 13b and 15a intermediately of the cop transport conveyor system 10.
Each of the tab readers 30 is provided to read a tab code set and stored for each cop magazine by the tab setter 20, discriminate a type of yarns accommodated in the cop magazine and selectively transport occupied magazine to a predetermined destination. For example, the tab reader 30 on the upstream side of the branch point 12a can discriminate whether an occupied magazine transported thereto on the forward conveyor 11 must necessarily advance into or should bypass the working process line 12. Meanwhile, the tab reader 30 on the upstream side of the branch points 13b can select one of the stock conveyors 13a in the stock line 13 for each type of yarns of cops in an occupied magazine, and consequently, the stock conveyors 13a can individually store thereon occupied magazines selected for individual types of yarns. Further, the tab reader 30 on the upstream side of the branch lines 15a can select a specific winder Wj in accordance with an individual type of a yarn.
A tab clearer 50 is disposed intermediately of the return conveyor 43 which forms part of the empty magazine conveyor system 40. The tab clearer is provided to clear the tab code set in the tab device of an empty magazine to assure the reliability of a resetting operation of a tab code by the tab setter 20.
A cop supplied to a winder Wj from a corresponding cop feed device 15b is at first subjected to a yarn end picking up operation by the yarn end pickup device Wja of the winder Wj and is then set for working on the winder Wj on which it is rewound, for example, into a cheese-like configuration, whereafter it is discharged to a next step by means of a conveyor system not shown. On the other hand, an empty bobbin (hereinafter referred to only as bobbin) from which a yarn has been unwound is checked that it has no remaining yarn thereon by means of a remaining yarn detecting device Wjb (j=1, 2, . . . , n) disposed at an exit end of the winder Wj, and then the bobbin is discharged onto a communicating conveyor 71 which makes part of the bobbin transport conveyor system 70.
The bobbin transport conveyor system 70 includes communicating conveyors 71, connecting conveyors 72 and a returning conveyor 73.
The communicating conveyors 71 individually communicate the winders Wj with the bobbin reservoirs Rj. A transverse conveyor 74 extends transversely to the communicating conveyors 71 so that any one of the winders Wj can communicate with an arbitrary one of the bobbin reservoirs Rj by way of the communicating conveyors 71 and the transverse conveyor 74.
The bobbin reservoirs Rj are provided to temporarily store therein bobbins discharged from the winders Rj and have bobbin loaders Rja (j=1, 2, . . . , n) provided therefor for transferring accumulated bobbins individually to the connecting conveyors 72.
The connecting conveyors 72 are provided to transfer bobbin loaders Rja to the returning conveyor 73. Each of the connecting conveyors 72 includes, as shown in FIG. 2, a bucket conveyor 72a for successively scooping up and feeding out bobbins from the corresponding bobbin loader Rja, and a transfer conveyor 72b for transferring a bobbin from the bucket conveyor 72a to the returning conveyor 73. Each of the connecting conveyors 72 has change-over mechanisms 72b1, 72b2, . . . incorporated therein for selectively transporting bobbins to a main transport path 73a, a spare main transport path 73b, a sub transport path 73c and a spare sub transport path 73d which generally constitute the returning conveyor 73.
The returning conveyor 73 supplies bobbins from within the bobbin reservoirs Rj to the spinning frames Si by way of the bobbin loaders Rja and the connecting conveyors 72.
The returning conveyor 73 may be constituted, for example, such that it includes an endless drive belt for receiving and moving empty bobbins in a laid down condition and a pair of side walls provided uprightly on the opposite side of the endless belt, and empty bobbins are laid successively in a row on the endless drive belt to transport the empty bobbins.
It is to be assumed here that there are up to 16 spinning frames Si (i=1, 2, . . . , m, m=16), and the six spinning frames S1, S2, . . . , S6 on the downstream side in the bobbin supplying direction form a first dedicated machine group G1; the four spinning frames S7, S8, S9, S10 on the upstream side of the first dedicated machine group G1 form a common machine group G12; and the six spinning frames S11, S12, . . . , S16 on the most upstream side form a second dedicated machine group G2. It is to be noted that each of the spinning frames Si has a pair of spindles not shown on the right- and left-hand sides thereof and further has a pair of bobbin receiving devices SiR and SiL (i=1, 2, . . . , m) for the right- and left-hand sides provided for the spindles. Further, FIG. 2 shows as up to four bobbin reservoirs Rj and four bobbin loaders Rja are used (n=4).
The main transport path 73a, spare main transport path 73b, sub transport path 73c and spare sub transport path 73d individually serve as conveyor lines for supplying bobbins from the transfer conveyors 72b to the spinning frames Si. The main transport path 73a is disposed very closely to the out end sides of the spinning frames Si and extend over the full extent from the spinning frame S16 to the spinning frame S1 so that it may supply bobbins to all of the spinning frames Si. Further, the main transport path 73a has change-over mechanisms 73a1, 73a2, . . . , 73a32 provided therefor corresponding to the bobbin receiving devices SiR and SiL of the individual spinning frames Si. The spare main transport path 73b joins the main transport path 73a on the upstream side very near to the spinning frame S16 on the most upstream side.
The sub transport path 73c and the spare sub transport path 73d are arranged in a juxtaposed relationship to each other and both join the main transport path 73a on the upstream side very near to the most upstream side one S6 of the spinning frames S1 to S6 which belong to the first dedicated machine group G1. Meanwhile, a communicating transport path 73e for communicating the sub transport path 73c with the main transport path 73a and a spare communicating transport path 73f for communicating the spare sub transport path 73d with the main transport path 73a are disposed on the upstream side very near to each of the spinning frames S7 to S10 which belong to the common machine group G12, and change-over mechanisms 73c1, 73c2, . . . and 73d1, 73d2, . . . corresponding to the communicating transport paths 73e and spare communicating transport paths 73f are incorporated in the sub transport path 73c and the spare sub transport path 73d, respectively. Each of such change-over mechanisms may include, for example, an opening and closing plate which is quickly opened or closed by an air cylinder or an electric actuator in response to an opening/closing control signal.
It is to be noted that each of the change-over mechanisms is provided to make a changing over operation so that a bobbin transported by the main transport path may be sent into a predetermined spinning frame, and where the spinning frames are of the opposite side type having spindles on the opposite right- and left-hand sides thereof, such change-over mechanisms are provided correspondingly on the opposite sides of the spinning frames so that bobbins may be supplied to the opposite sides of the spinning frames.
The bobbin supply system for spinning frames having such a construction as described above operate in the following manner.
It is assumed here that the spinning frames S1 to S6 which belong to the first dedicated machine group G1 form a first group while the spinning frames S7 to S16 which belong to the common machine group G12 and the second dedicated machine group G2 form a second group, and the spinning frames are working with different types of yarns set thereon. In this instance, two different types of bobbins for different types of yarns are discharged from the winders Wj and individually thrown into the different bobbin reservoirs R1 and R2 by way of the corresponding communicating conveyors 71 and the transverse conveyor 74. Thereupon, the other bobbin reservoirs R3 and R4 may receive yarns of the same types with the bobbin reservoirs R1 and R2 or otherwise may be left at rest. It is assumed here, however, that bobbins to be used on the spinning frames Si (i=1, 2, . . . , 6) which belong to the first group are thrown into the bobbin reservoir R1 while bobbins to be used on the spinning frames Si (i=7, 8, . . . , 16) which belong to the second group are thrown into the bobbin reservoir R2.
The bobbin loader R1a operates in response to a bobbin requesting signal from any one of the spinning frames Si which belong to the first group and can thus supply a bobbin from within the bobbin reservoir R1 to the spinning frame Si by way of the corresponding bucket conveyor 72a, transfer conveyor 72b, and sub transport path 73c or main transport path 73a. In particular, a bobbin which has been transferred from a bucket conveyor 72a to a corresponding transfer conveyor 72b is then transferred to the sub transfer path 73c by a corresponding change-over mechanism 72 at the location at which the transfer conveyor 72b crosses the sub transport path 73c, whereafter the bobbin is transferred to the main transport path 73a at the last end of the sub transport path 73c. Consequently, the bobbin can be sent into the bobbin receiving device SiR or SiL of the predetermined spinning frame Si by suitably operating one of the change-over mechanisms 72ak-1 and 72ak (k=2i) corresponding to the predetermined spinning frame Si.
Similarly, a bobbin within the bobbin reservoir R2 can be supplied to an arbitrary one of the spinning frames Si belonging to the second group by way of the corresponding bobbin loader R2a, bucket conveyor 72a, transfer conveyor 72b and main transport path 73a. In this instance, a corresponding change-over mechanism 72b1 transfers the bobbin from the transfer conveyor 72b to the main transport path 73a.
In this instance, since there is no overlapping portion between bobbin supply routes to spinning frames Si and Sj (1≦i≦6, 7≦j≦16) which belong to different groups from each other, they can receive supply of bobbins in a simultaneous relationship with each other.
When the type of yarns to be set on the spinning frames Si which belong to the first group is to be changed, new bobbins for use with a new type of yarns are prepared in the bobbin reservoir R3 in advance, and then, upon changing over of the yarn type, bobbins of the new type can be supplied to the spinning frames Si of the first group by way of the bobbin loader R3a, transfer conveyor 72b, spare sub transport path 73d and main transport path 73a. Supply of bobbins of a new type to the spinning frames Si belonging to the second group takes place in a similar manner, and new bobbins prepared in the bobbin reservoir R4 may be supplied by way of the spare main transport path 73b.
Subsequently, such a case will be examined that some of the spinning frames S7, S8, . . . , S10 which belong to the common machine group G12 are to be changed from the second group to the first group. In this instance, bobbins for use with the first group should be supplied in place of bobbins for use with the second group in response to a bobbin requesting signal from a spinning frame Sk which should be changed from the second group to the first group. In particular, if it is assumed that the two spinning frames S7 and S8 are to be changed from the second group to the first group, then a bobbin for use with the first group which is accommodated in either one of the bobbin reservoirs R1 and R3 is transported to the main transport path 73a by way of the sub transport path 73c or spare sub transport path 73d and the communicating transport path 73d or spare communicating transport path 73f corresponding to the spinning frame S8. Consequently, the position at which the sub transport path 73c or spare sub transport path 73d joins the main transport path 73a can be substantially changed to a position on the upstream side very near to the spinning frame S8. Accordingly, the spinning frames S7 and S8 can be thereafter treated as they belong to the first group. In this instance, however, since the communicating transport path 73e and spare communicating transport path 73f corresponding to the spinning frame 8 are used, flows of bobbins on the sub transport path 73c and spare sub transport path 73d should be changed over by the change-over mechanisms 73c2 and 73d2 corresponding to such transport paths 73e and 73f.
Since this can be realized in a quite similar manner with all of the spinning frames Si (i=7, 8, . . . , 10) which belong to the common machine group G12, the spinning frames S7 to S10 can be divided into two groups individually including arbitrary numbers of spinning frames in accordance with required production lot amounts for individual types of yarns so that they may individually belong to either one of the first and second groups. Accordingly, the boundary between the first and second groups can be selected arbitrarily.
While the sub transport path may be constructed so that it may supply at least two types of bobbin as described above, where a spare sub transport path is provided in a juxtaposed relationship and extends to a position at which the sub transport path joins the main transport path and also the communicating transport paths are provided with spare communicating transport paths accordingly, new bobbins which are to be supplied after changing over can be transported onto the spare sub transport path in advance. Consequently, when the type of bobbins is to be changed over, the time required for supply of bobbins can be reduced.
Other Embodiments
It is a matter of course that the system shown in FIG. 2 may include an arbitrary total number of spinning frames Si and each of the first and second dedicated machine groups G1 and G2 and the common machine group G12 may include an arbitrary number of spinning frames Si. However, the sub transport path 73c and the spare sub transport path 73d should join the main transport path 73a on the upstream side very close to a most upstream side one of the spinning frames Si which belong to the first dedicated machine group G1 while the communicating transport paths 73e and the spare communicating paths 73f should be provided for all of the spinning frames Si which belong to the common machine group G12.
The spinning frames Si may be divided into three dedicated machine groups G1, G2 and G3 and two common machine groups G12 and G13 as shown in FIG. 3. In this instance, two sub transport paths 73c and 73g and two spare rib transport paths 73d and 73h should be provided for supplying bobbins to the dedicated machine groups G1 and G2 except the dedicated machine group G3 on the most upstream side while communicating transport paths 73e and 73m and spare communicating transport paths 73f and 73n should be provided for the individual spinning frames Si which belong to the common machine groups G12 and G23, respectively.
Further, the present embodiment can be accommodated for expansion to an arbitrary number of dedicated machine groups G1, G2, . . . and common machine groups G12, G23, . . .
Further, in each of the embodiments described above, the spare main transport path 73b and the spare sub transport path 73d can be omitted as shown in FIG. 4. In particular, referring to FIG. 4, the main transport path 73a and the sub transport path 73c may be connected in a branching manner at the starting ends thereof to the bobbin reservoirs R2 and R4 and the bobbin reservoirs R1 and R3, respectively, in preparation for changing of a type of a yarn for a spinning frame Si. It is to be noted that each of the main transport path 73a and the sub transport path 73c must only be constructed generally such that at least it can alternatively supply two different types of bobbins including bobbins in use at present and bobbins to be used anew, and upon changing to a new type of yarns, old bobbins in a bobbin reservoir Rj should be replaced by new bobbins. However, where the main transport path 73a and the sub transport path 73c are constructed such that each of them can supply three or more types of bobbins, then the opportunities for such replacing operation of bobbins are reduced, allowing more convenient use of the bobbin supply system. | A bobbin transport system for spinning frames for supplying bobbins from bobbin reservoirs to spinning frames in a spinning mill. The spinning frames are divided into dedicated machine groups and a common machine group or groups. Bobbins are supplied to the dedicated machine groups by way of a main transport path and/or a sub transport path, and a communicating transport path for transferring bobbins from the sub transport path to the main transport path is provided for each of the spinning frames of the common machine group or groups. The bobbin transport system for spinning frames makes it possible to change the allotment of numbers of spinning frames for different types of yarns to be set for the common machine group or groups and to distribute different types of bobbins accurately to predetermined spinning frames thereby to enable production of several articles by small quantities without deteriorating the availability factor of the entire spinning frames. | 3 |
BACKGROUND OF THE INVENTION
The present invention relates to an evaluation data collecting system for collecting the operation status of processing nodes such as a host computer, a distributed computer and a terminal device which are connected with one another, and more particularly to the evaluation data collecting system for an information processing system for storage, correcting and outputting of evaluation data which is preferable to system evaluation of the response time in these on-line systems.
For example, in the system evaluation method for the response time in conventional on-line systems, the evaluation data for each processing node is stored in the format peculiar to the processing node, the data is collected for each processing node to be edited, processed and output individually, and thereafter the data is correlated by manual operation to obtain materials for system evaluation. The response time is evaluated using the materials thus obtained. Such technology is disclosed in JP-A-2-310741.
As described above, in the prior art, several kinds of evaluation data for each of processing nodes, such as a host computer, a distributed computer and a terminal device, are stored in the format peculiar to each of these processing nodes. It takes a relatively long time to correlate the several kinds of evaluation data for each processing node. Further, formats for the several kinds of evaluation data are different for different processing nodes (e.g. the number of items) so that the processing node cannot be specified to collect the correlated evaluation data collectively.
Furthermore, the evaluation data refers to resource load information (CPU using rate, channel using rate, etc.), batch processing state information, etc. which are related to the response information. Processing nodes includes the host computer, distributed computer, terminal device, etc.
SUMMARY OF THE INVENTION
An object of the present invention is to provide an evaluation data collecting system for an information processing system for collection, storage and outputting evaluation data which can easily correlate several kinds of evaluation data for each processing node so that it can collect the evaluation data for all processing nodes and can edit and process the collected evaluation data in the processing node that required the evaluation data to be collected.
In order to attain the above object of the present invention, there is provided an evaluation data collecting system for an information processing system which connects plural processing nodes with one another by communication paths and collects the evaluation data representative of the operation state of each of the processing nodes from any of the processing nodes, including an I/O unit provided at each processing node so as to input a collection request of the evaluation data for a subject processing node and other processing nodes and to output the evaluation data from the other processing nodes; a processing unit provided at each of the processing nodes so as to process an input of the collection request for the evaluation data and an output of the evaluation data at the I/O unit; and a storage unit provided, at each of the processing nodes so as to provide the evaluation data for each processing node at issue as well as the other processing nodes, with a time element to synchronize data transfer between said processing nodes and so as to store the evaluation data for each processing node at issue as well as the other processing nodes in substantially the same data format.
The plural processing nodes include a terminal node, a distributed host node connected with the terminal node through a LAN (Local Area Network) and a host node connected with the distributed host node through a WAN (Wide Area Network).
Each of said processing node, distributed host node and host node includes the I/O unit, the processing unit and the storage unit.
The evaluation data includes response information, resource load information and batch processing state information. The response information includes records of an input time when a transaction request for collecting evaluation data for the other nodes is input for any one of the terminal node, distributed host node and host node and an output time when the transaction is output from the one node to the other nodes. The resource load information includes records of the using rate of a CPU (Central Processing Unit) in the processing unit and the channel using rate for data input/output for a data storage device in the storage unit. The batch processing state information includes records of starting and ending times of batch processing when the CPU in the processing unit are used for the batch processing.
Each of the response information, resource load information and batch processing information includes an information discrimination code, for discriminating each of these items of information from other items, and a storing time. The storing time of the response information is data indicating when the transaction has been stored in the storage unit, what data the resource information represents when the CPU using rate and channel using rate have been stored in the storage unit, and what data the batch processing state information represents when a batch processing program has been stored in the storage unit.
The data format of each of the response information, resource load information and batch processing state information includes an information discrimination code, a storing time and storage area as time elements in succession from its start.
The same information discrimination code and storage area among the response information, resource load information and batch processing state information correlate at least these items of information so that evaluation data is specified for any one of said terminal node, distributed host node and host node.
Each item of information of the response information, resource load information and batch processing state information with their information discrimination codes and storage areas corresponding with one another and their storing times corresponding with one another is supplied to each of the host node, distributed host node and terminal node.
As described above, the plural processing nodes are caused to have the evaluation data in the same data format and correlated in terms of the information discrimination code and storage area, and the evaluation data is given the storing time indicating when the data has been created. So, the evaluation data for all of the processing nodes at any time can be collected and output in any processing node. Therefore, the performance between the processing nodes in a hierarchical form can be efficiently evaluated without using manual operation and that of the specific processing node can also be easily evaluated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing an arrangement of the on-line system constituting a system for storing, collecting and outputting evaluation data according to the present invention;
FIG. 2 is a flowchart for explaining the processing of storing evaluation data in each processing node;
FIGS. 3A, 3B and 3C are views showing examples of formats of evaluation data;
FIG. 4 is a flowchart showing the processing of collecting evaluation data in a terminal node;
FIG. 5 is a flowchart showing the editing, processing and outputting of evaluation data in the terminal node; and
FIG. 6 is a view for explaining a typical example of the evaluation data collected in the terminal node.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now referring to the drawings, an explanation will be given of an embodiment of the present invention.
FIG. 1 shows the arrangement of the on-line system according to one embodiment of the present invention. As seen from FIG. 1, in this embodiment, the on-line system is made up of three processing nodes. A host node processing unit 31 of a host node 31a includes a host node storage unit 32 for storing the evaluation data within the host node 31a, a host node input unit 30 for requesting the collection of evaluation data for processing nodes inclusive of the host node 31a itself and the editing, processing and outputting thereof, and a host node output unit 33 for performing the editing, processing and outputting of the evaluation data for the processing nodes inclusive of the host node 31a itself. A distributed host node processing unit 21 of a host node 21a includes a distributed host node storage unit 22 for storing the evaluation data within the distributed host node 21a, a distributed host node input unit 20 for requesting the collection of evaluation data for processing nodes inclusive of the distributed host node 21a itself and the editing, processing and outputting thereof, and a host node output unit 23 for performing the editing, processing and outputting of the evaluation data for the processing nodes inclusive of the distributed host node 21a itself. A terminal node processing unit 11 of a terminal node 11a includes a terminal node storage unit 12 for storing the evaluation data within the terminal node 11a, a terminal node input unit 10 for requesting the collection of evaluation data for processing nodes inclusive of the terminal node 11a itself and the editing, processing and outputting thereof, and a terminal node output unit 13 for performing the editing, processing and outputting of the evaluation data for the processing nodes inclusive of the terminal node 11a itself.
The host node processing unit 31 is connected to the distributed host node processing unit 21 through a WAN (Wide Area Network) 50, and another host node 41 is also connected with the WAN 50. The distributed host node processing unit 21 is connected to the terminal node processing unit 11 through a LAN (Local Area Network) 51.
FIG. 2 shows the flow of the processing of storing evaluation data in the terminal node 11a which is one of the processing nodes. In FIG. 2, for example, when the terminal node 11a makes an inquiry of the distributed host node 21a and the host node 31a, it performs response information storing processing 111 which stores, in the terminal node storage unit 12, response information 121 which includes an input time when the terminal node processing unit 11 has received an inquiry transaction from the terminal node input unit 10, an output time when this transaction has issued from the terminal node processing unit 11 to the distributed host node 21a and the host node 31a through the LAN 51, another input time when the terminal node processing unit 11 has received a transaction from the distributed host node 21a and the host node 31a through the LAN 51 and another output time when the transaction has been sent to the terminal node output unit 13. A typical format of the response information 121 is shown in FIG. 3A.
Likewise, in the terminal node 11a, resource load information storing processing 112 stores the using rate of a CPU in the terminal node 11a within a fixed interval in the terminal node storage unit 12. A typical format of the resource load information 122 is shown in FIG. 3B.
Likewise, in the terminal node 11a, batch processing state information storing processing 113 stores, in the terminal node storage unit 12, e.g. the starting and ending times of the batch processing in the terminal node 11a. A typical format of the batch processing state information 123 is shown in FIG. 3C.
In connection with FIG. 2, an explanation has been given of the storing of the response information 121, resource load information 122 and batch processing state information 123 which are used as evaluation data in the terminal node 11a. But, in the same manner, the distributed host node 21a and the host node 31a also store the evaluation data. As described above, the response information 121, resource load information 122 and batch processing state information 123 are stored in the terminal node storage unit 121. But, more specifically, all of the respective storage units 32, 22 and 12 of the host node 31a, distributed host node 21a and terminal node 11a, explained in connection with FIG. 1, include storage areas for the response information 121, resource load information 122 and batch processing state information 123, as shown in FIGS. 3A, 3B and 3C, respectively. In short, all of the respective storage areas of the host node storage unit 32, distributed host node storage unit 22 and terminal node storage unit 12 have the same format for the evaluation data.
A further explanation will be given of FIGS. 3A, 3B and 3C. Where the response information 121 is to be used for the terminal node 11a, i.e., it is stored in the storage area of the terminal node storage unit 12, an area 121a is used to record the input time when a transaction is input from the terminal node input unit 10 to the terminal node 11a and the output time when the transaction is output from the terminal node processing unit 11 of the terminal node 11a via the LAN 51 to the distributed host node 21a or host node 31a, and an area 121b is used to record the input time when a transaction from the distributed host node 21a or host node 31a is input to the terminal node 11a via the LAN 51 and the output time when the transaction is output to the terminal node output unit 13 through the terminal node processing unit 11.
Where the response information 121 is to be used for the distributed host node 21a, the area 121a is used to record the input time when the distributed host node processing unit 21 has received a transaction from the terminal node 11a through the LAN 51 and the output time when the transaction is output from the distributed host node 21a via the WAN 50 to the host node processing unit 31 of the host node 31a, and the area 121b is used to record the input time when the distributed host node processing unit 21 has received a transaction from the host node processing unit 31 through the WAN 50 and the output time when the transaction is output from the distributed host node processing unit 21 to the terminal node 11a through the LAN 51.
Where the response information 121 is to be used for the host node 31a, the area 121a is used to record the input time when the host node processing unit 31 has received a transaction from the distributed host node 21a or the terminal node 11a and the output time when the transaction is output from the host node processing unit 31 via the WAN 50 to the distributed host node processing unit 21 of the distributed host node 21a.
As in the terminal node 11a described above, both the host node 31a and the distributed host node 21a can perform the transaction input/output operation by means of the input and output units 30 and 33 of the former and the input and output units 20 and 23 of the latter. A serial number is given for each transaction inquiry. A transaction name refers to the data representing the name of work which e.g. the terminal node 11a inquires from the distributed host node 21a. A storage area refers to the data indicating in which of the terminal node storage unit 12, distributed host node storage unit 22 and host node storage unit 32 the transaction at issue has been stored. A storage time refers to the data indicating when the transaction designated by the transaction name has been in the area designated by the storage area. An information discrimination code refers to the data for discriminating the response information 121, resource load information 122 and batch processing state information 123 from one another.
Where the resource load information 122 shown in FIG. 3B has been stored in the storage unit 12 of the terminal node 11a, resource load data refers to the data representing the using rate of CPU included in the terminal node 11a itself and that of a channel for data input/output such as a disk unit in the terminal node 11a. A storage area refers to the data indicating in which of the terminal node storage unit 12, distributed host node storage unit 22 and host node storage unit 32 the transaction at issue has been stored. A storage time refers to the data indicating when the resource load data has been in the area designated by the storage area. An information discrimination code refers to the data for discriminating the response information 121, resource load information 122 and batch processing state information 123 from one another.
Where the batch processing state information 123 shown in FIG. 3C has also been stored in the storage unit 12 of the terminal node 11a, starting and ending times refer to the data representing the times for starting and ending the batch processing which the terminal node 11a itself has performed. A serial number refers to the data indicating the serial number given for each creation of batch processing. A batch name refers to the data indicating the serial number given for each batch processing. A storage area refers to the data indicating in which of the terminal node storage unit 12, distributed host node storage unit 22 and host node storage unit 32 the transaction at issue has been stored. A storing time refers to the data indicating when the batch program designated by the batch name has been in the area designated by the storage area. An information discrimination code refers to the data for discriminating the response information 121, resource load information 122 and batch processing state information 123 from one another.
As described above, the response information 121, resource load information 122 and batch processing state information 123 shown in FIGS. 3A, 3B and 3C have been in the storage areas of the respective storage units 32, 22 and 12 of the host node 31a, distributed host node 21a and terminal node 11a.
If the above described information discrimination code indicates that the storage areas of the response information 121, resource load information 122 and batch processing state information 123 agree with one another, these items of information 121, 122 and 123 are correlated with each other.
FIG. 4 is a flowchart of the processing for collecting evaluation data in the terminal node 11a serving as a processing node. It is assumed that the program represented by this flowchart is also included in the host node 31a and distributed host node 21a as well as the terminal node 11a. Along with the flowchart shown in FIG. 4, an explanation will be given of the processing of collecting evaluation data in the terminal node 11a.
Collection request processing 114 periodically and automatically requests that the evaluation data for other processing nodes (i.e., the host node 31a and distributed host node 21a) and the terminal node 11a itself be input. Collection request 104 manually requests that the evaluation data be input as necessity requires. In response to the request from the collection request processing 114 or collection request 104, stored information collecting processing 115 for the host node inputs the evaluation data from the storage unit 32 of the host node 31a and stores it in the storage area of the terminal node storage unit 12 as the evaluation data 124 for the host node 31a. The stored evaluation data 124 includes the response information 121, resource load information 122 and batch processing state information 123 stored in the same area, i.e. correlated with one another.
Stored information collecting processing 116 for the distributed host node inputs the evaluation data from the storage unit 22 of the distributed host node 21a and stores it in the storage area of the terminal node storage unit 12 as the evaluation data 125 for the host node 21a. The stored evaluation data 125 also includes the response information 121, resource load information 122 and batch processing state information 123 stored in the same area.
Stored information (i.e. evaluation data for the terminal node 11a itself) collecting processing 117 for the terminal node extracts the evaluation data from the storage unit 12 of the terminal node 11a and stores it in the storage area of the terminal node storage unit 12 as the evaluation data 126 for the terminal node 11a. The stored evaluation data 126 also includes the response information 121, resource load information 122 and batch processing state information 123 stored in the same area.
Not only the terminal node 11a but the host node 31a and distributed host node 21a can input the evaluation data for the processing nodes other than themselves, along the flowchart of FIG. 4. For example, the distributed host node 21a stores, in the storage area of its storage unit 22, the respective evaluation data 126, 124 and 125 for the terminal node 11a, host node 31a and itself. The host node 31a also stores the evaluation data 124, 125 and 126.
FIG. 5 shows the flow of the processing of editing, processing and outputting evaluation data in the terminal node 11a serving as a processing node. In the example of FIG. 5, the terminal node 11a inquires through its input unit 10 a transaction of editing, processing and outputting from the distributed host node 21a and host node 31a and outputs the evaluation data for itself at its output unit 13. When the editing/processing/outputting for the evaluation data for the host node 31a, distributed host node 21a and terminal node 11a are to be performed, an editing/processing/outputting request 105 is manually input through the terminal node input unit 10. Then, in evaluation data input processing 118, as described above, these evaluation data 124, 125 and 126 are extracted successively from the terminal node storage unit 12. The evaluation data 124, 125 and 126 used in the processing 118 have the same storage area, and the response information 121, resource load information 122 and batch processing state information 123 of each of the evaluation data 124, 125 and 126 have the same storing time. In editing/processing/outputting processing 119, the evaluation data 124, 125 and 126 are edited in their output format to be output as a sheet from the terminal node output unit 13.
FIG. 6 shows the sheet on which the output evaluation data has been written. Referring to FIG. 6, the output result will be explained. As described above, the processing nodes, the evaluation data for which is to be collected, include the host node 31a, distributed host node 21a and terminal node 11a. With respect to the evaluation data 124 for the host node 31a, a CPU using rate and a channel using rate correspond to the resource load information 122, a batch processing state corresponds to the batch processing state information 123, and a response (in the host node) and the number of transactions correspond to the response information 121. With respect to the evaluation data 125 for the distributed host node 21a, the CPU using rate and the channel using rate correspond to the resource load information 122, the batch processing state corresponds to the batch processing state information 123, and the response (in the distributed host node) and the number of transactions correspond to the response information 121. With respect to the evaluation data 126 for the terminal node 11a, the CPU using rate corresponds to the resource load information 122, the batch processing state corresponds to the batch processing state information 123, and the response (in the terminal node) corresponds to the response information 121. The times will be explained below. They represent the storing times for the response information 121, resource load information 122 and batch processing information 123. Concerning the resource load information 122 generally designated by ◯ marks, the CPU using rate and channel using rate are represented in term of % for each unit time. Concerning the batch processing state information 123, the batch processing state is represented by the starting and ending times of the batch processing. Concerning the response information 121, the response is represented by the input and output times of a transaction in both transmission directions, and the number of transactions is generally represented by ◯ marks which indicate the number of transactions for each unit time. It should be noted that the response information 121 for the terminal node 11a does not include the number of transactions.
As described above, the host node 31a, distributed host node 21a and terminal node 11a are provided with the evaluation data in the same format and correlated with one another in the information discrimination codes and storage areas, and the evaluation data are caused to include the storing times representing when they have been created. For this reason, at any time, the respective evaluation data 124, 125 and 126 for the host node 31a, distributed host node 21a and terminal node 11a can be collected, edited and output in any of the host node 31a, distributed host node 21a and terminal node 11a. Therefore, the performance between the processing nodes in a hierarchical form can be efficiently evaluated without using manual operation and that of the specific processing node can also be easily evaluated.
In the above embodiment, an explanation has been mainly given of the case where collection of the evaluation data for the processing nodes, i.e., the host node 31a and distributed host node 21a is requested by the terminal node 11a. But, it is needless to say that the evaluation data 124, 125 and 126 can be collected by the host node 31a or distributed host node 21a like the terminal node 11a. Further, in the above embodiment, the evaluation data has been collected in a dedicated transaction, but can be also collected in the format in which it is supplied in a usual data transfer.
Many different embodiments of the present invention may be constructed without departing from the spirit and scope of the invention. It should be understood that the present invention is not limited to the specific embodiments described in this specification. To the contrary, the present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the claims. | An evaluation data collecting system for an information processing system which connects plural processing nodes to each other by communication paths. The evaluation collecting system includes an I/O unit provided at each of the processing nodes so as to input an collection request of the evaluation data for a processing node at issue and other processing nodes and to output the evaluation data from the other processing nodes; a processing unit provided at each of the processing nodes so as to process an input of the collection request for the evaluation data and an output of the evaluation data at said I/O unit; and a storage unit provided at each of the processing nodes so as to provide the evaluation data for each processing node at issue and that for the other processing nodes with a time element to synchronize data transfer between the processing nodes and to store the evaluation data for each processing node at issue and the other processing nodes in substantially the same data format. Thus, the evaluation data collecting system can collect the evaluation data representative of the operation state of each of the processing nodes from any of the processing nodes. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to a digital signal recording and playback apparatus, and more particularly to a digital signal recording and playback apparatus capable of satisfactorily recording or playback of a digital signal even in the case of running a magnetic tape at high speed.
For the rotary drum of a Digital Audio Tape recorder (DAT) which is an apparatus for recording and playback of a digital audio signal using a magnetic head, there is known a rotary drum in the system around which a magnetic tape (hereinafter simply referred to as a "tape") 3 is wound in an angular range of 90 degrees of a rotary drum 2 on which two rotary heads 1a and 1b having different azimuth angles are provided at an angular interval of 180 degrees as shown in FIGS. 1A and 1B.
In these figures, reference numerals 41 to 44 denote guide rods for guiding the tape 3 for the purpose of allowing the tape 3 to be in contact with the rotary drum 2, respectively.
There is an established Industry Standard for the DAT (which may be referred to as simply "the DAT format" in this specification) which specifies or recommends specifications of tape format and of related mechanical components and their performances. According to the, standard, track length L of 2.3501 cm, a track angle θ of 6 degrees 22 minutes 59.5 seconds, and a tape transport speed of 0.815 cm/sec are standardized, and a drum diameter of 30 mm and drum rotational speed of 2,000 revolutions per minute (r.p.m.) are recommended for one of the various operating modes. And a lead angle of 6 degrees 22 minutes, which will be explained later, is recommended also.
For a convenience of explanation of this invention, all of those standardized or recommended figures in the DAT format are referred to as "standard" values in this specification, further, recording and reproducing operation under those "standard" values is referred to as "standard" mode unless otherwise specified.
The above-mentioned rotary drum 2 has the standard diameter of 30 mm and rotates at the standard rotational speed of 2000 revolutions per minute (hereinafter referred to as 2000 r.p.m), and the tape 3 is transported at the standard speed of 0.815·cm/sec. Furthermore, the lead or introduction angle when the tape 3 is wound onto the rotary drum 3 is the standard lead angle 6 degrees 22 minutes (hereinafter referred to as 6°', etc.). The lead angle is the inclination of the rotary axis of the rotary drum with respect to the perpendicularly transversed direction of the magnetic tape obliquely wrapped around the rotary drum. The relationship between the rotational direction R of the rotary drum 2 and the running direction S of the magnetic tape 3 is actually determined as shown in FIG. 1. As a result, at the time of recording, the digital signal is recorded while forming tracks as a head scanning locus 4a and 4b on the tape 3 as shown in FIG. 2, and a track angle θ defined by these tracks and the running direction S of the tape 3 is equal to 6°22'59.5" standardized in the DAT format.
On the other hand, at the time of playback, the magnetic heads 1a and 1b provided and being angularly spaced to each other by an angle of 180 degrees alternately scan these tracks 4a and 4b consecutively formed without a guard band therebetween, whereby the recorded digital signal is read out. At this time, the time required until the magnetic head 1a or 1b rotates by an angle of 90 degrees to scan one track is 7.5 milliseconds (msec).
In such an arrangement where the tape 3 is wound in an angular range of 90 degrees onto the rotary drum 2 on which the magnetic heads 1a and 1b are provided at an interval of 180 degrees, there is a 7.5 msec blank period during which the tape is not contacted nor scanned by either magnetic head 1a or 1b, between the end of one track scan by one head and the beginning of the subsequent track scan by another head. Accordingly, in order to adapt the continuous recording or playback digital signal to such an intermittent operation which is carried out only when the magnetic head is scanning the track, time compression processing is implemented to the digital signal.
In general, the time required for dubbing a digital audio signal from one DAT to another DAT having a rotary drum constituted as shown in FIG. 1 is equal to the time required for reproducing the signal on the tape at the standard speed. For example, in the case of dubbing a two hour length of digital program, it takes two hours which is the same as that at the time of playback for normal listening. On the other hand, most tape recorders of analog system so-called "doubledeck machines" have a function capable of carrying out dubbing at double speed or a speed higher than a standard one. Under these circumstances, a high speed dubbing function is desired also for DATs.
Furthermore, in the case of using DAT for backing up a hard disk, etc. for use in a computer system as a data streamer, or in other similar cases, there is a need for carrying out recording/playback of data at a high speed. The transfer speed in this case is restricted by the basic electrical and mechanical characteristics of the DAT.
If an attempt was made to carry out a dubbing, e.g., at a quadruple tape speed, i.e. 4 times the standard tape speed, using the apparatus of FIG. 1, it would require to rotate the rotary drum at 8000 r.p.m. which is four times faster than the standard speed. However, since the relative speed between the magnetic head 1a or 1b scanning the tracks 4a and 4b on the tape 3 and the tape 3 would also become equal to a value four times as large, the recording/playback frequencies become extremely high. As a result, the signal level would be lowered by the inherent characteristics of the magnetic head 1a or 1b and the rotary transformer (not shown) provided within the rotary drum 2 to conduct transmission and reception of signals, resulting in the problem that it would be unable to carry out recording and playback in full fidelity. Furthermore, at this time, the modulator circuit and the demodulator circuit, etc. must perform circuit operation at four times the speed.
In addition, there would be a problem of revolving the rotary drum 2 at 8000 r.p.m. which is a value four times larger than the standard value. There would likely develop unstable tape running in the tape transport system.
SUMMARY OF THE INVENTION
This invention has been made in view of the above circumstances and its object is to provide a digital signal recording and playback apparatus capable of maintaining stable circuit operation of the modulator/demodulator circuits as well as the operation of the tape running system, and of carrying out recording and playback of digital signals at high speed in full fidelity.
To achieve the above object, when the running speed of the magnetic tape is selected to a value N times (N≧1, e.g., two times or four times) as much as the standard speed (0.815 cm/sec) and the number of revolutions of the rotary drum is selected to a value M times (M<N, e.g., one time or two times) as large as the standard speed, in order to allow the relative speed between the magnetic heads and the magnetic tape to be equal to a value M times as large as the standard relative speed for the DAT, and to enable recording of a digital signal in conformance to the DAT format and/or playback of the digital signal recorded on the magnetic tape in conformance to the standard head scanning locus rotated in the DAT format, the diameter of the rotary drum is modified to a value (e.g., 30.077 mm) slightly larger than the standard diameter (30 mm) , and the lead angle is modified to a value (e.g., 6°21'0.82") slightly smaller than the standard one (6°22').
Furthermore, when the running speed of the magnetic tape is modified to a value N times (N≧1, e.g., two times) the standard speed, and the number of revolutions of the rotary drum is also modified to a value N times as large as that, in order to allow the relative speed of the magnetic heads and tape to be equal to the afore-mentioned standard relative speed, and to enable recording of a digital signal in conformance to the DAT format and/or playback of the digital signal recorded on the magnetic tape in conformance to the standard head scanning locus, the diameter of the rotary drum is modified to a value (e.g., 15.039 mm) smaller than the standard one and the lead angle is modified to a value (e.g., 6°21'0.82") smaller than the standard lead angle.
There are other possibilities of arrangement employed wherein the diameter of the rotary drum is, e.g., 30.077 mm, four magnetic heads are provided instead of two, the lead angle is selected to, e.g., 6°21'0.82", and the magnetic tape is wound in an angular range of 90 degrees, it is possible to allow the rotational speed of the rotary drum to be 1000 r.p.m. for the standard tape running speed, or to allow the rotational speed of the rotary drum to be 2000 r.p.m. for the double (two times standard speed) tape running speed, or to allow the rotational speed of the rotary drum to be 4000 r.p.m. for the quardruple tape running speed. Thus, even in the case of carrying out recording or playback up to quadruple tape running speed, the recording and playback apparatus can record or playback a digital signal, e.g., a digital audio signal, etc. with the characteristic and the operating performance designed for the double tape running speed.
Furthermore, when there is employed a construction wherein the diameter of the rotary drum is modified to, e.g., 15.039 mm, two magnetic heads are provided, the magnetic tape is wound in an angular range of 180 degrees, and the lead angle is modified to, e.g., 6°21'0.82", it is possible to allow the rotational speed of the rotary drum to be 2000 r.p.m. for the standard tape running speed, and to allow the rotational speed of the rotary drum to be 4000 r.p.m. for the double speed tape running. Thus, even in the case of carrying out recording or playback at the double tape running speed, the recording and playback apparatus can record or playback a digital signal, e.g., a digital audio signal, etc. with the same characteristics and operating performance designed for those of the conventional DATS.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIGS. 1A and 1B are a plan view and a perspective view showing a rotary drum of DAT as an example of a conventional signal recording and playback apparatus, respectively;
FIG. 2 is a plan view showing the standard track configuration with respect to a digital signal recording tape according to the Industry Standard for DAT;
FIG. 3 is a plan view showing a rotary drum as the essential part of a digital signal recording and playback apparatus according to a first embodiment of this invention;
FIG. 4A is a vector diagram showing the running velocity of the magnetic tape, tangential velocity of the magnetic head, and a relative velocity between both these velocities, and FIG. 4B is a table in which vectors of respective velocities in FIG. 4A are comprehensibly arranged in order;
FIG. 5 is a block diagram showing the schematic circuit configuration of the Digital Audio Tape recorder (DAT) using the rotary drum shown in FIG. 3;
FIG. 6 is a block diagram showing a control signal generator circuit for controlling the recording head changeover switch 10 shown in FIG. 5;
FIG. 7(a-g) is a timing chart showing timings of control signals used for controlling the recording head;
FIG. 8 is a block diagram showing a control signal generator circuit for controlling the playback head changeover switch 11 shown in FIG. 5;
FIG. 9 (a-g) is a timing chart showing timings of control signals used for controlling the playback head;
FIG. 10 is a timing chart showing dubbing operations in the case of carrying out a dubbing using two DATs shown in FIG. 5;
FIG. 11 is a block diagram showing a DAT using the rotary drum shown in FIG. 3 and constructed as the double deck type DAT having heads exclusively used for recording and heads exclusively used for playback;
FIG. 12 is a timing chart showing the operation of the DAT of FIG. 11;
FIG. 13 is a block diagram showing the configuration in the case where the DAT of the first embodiment is used as a data streamer;
FIG. 14 is a plan view showing a rotary drum according to a second embodiment of this invention;
FIG. 15A is a vector diagram showing the running velocity of the magnetic tape, the tangential velocity of the magnetic head, and the relative velocity between both these velocities, and FIG. 15B is a table in which vectors of respective velocities of FIG. 15A are comprehensibly arranged in order;
FIG. 16 is a block diagram showing a circuit configuration of DAT using the rotary drum according to the second embodiment shown in FIG. 14; and
FIG. 17 is a timing chart showing the operation of the DAT of FIG. 14.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of a digital signal recording and playback apparatus according to this invention will be described in detail with reference to the attached drawings.
FIG. 3 shows a rotary drum 5 and its peripheral arrangement in a first embodiment of this invention. The rotary drum 5 is provided coaxially with a stationary drum (not shown) as usual. The diameter of the rotary drum 5 shown in this figure is 30.077 mm, while the diameter of the standard rotary drum 2 shown in FIG. 1 is 30 mm. The rotary drum 5 has four magnetic heads 6a, 6b, 6c and 6d (6a and 6c are plus azimuth heads, and 6b and 6d are minus azimuth heads, respectively.). In addition, tape 3 is obliquely wound onto the rotary drum 5 at a lead angle of 6°21'0.82". This is also different from the standard value of 6°22' for the conventional apparatus. In FIG. 3, reference numerals 41 to 44 denote guide rods similarly to the conventional ones, respectively.
FIG. 4A is a vector diagram showing the running velocity of the tape, the tangential velocities of magnetic heads 6a to 6d, and the relative velocities between the magnetic heads 6a to 6d and the tape 3 when the apparatus constructed in accordance with the abovementioned specifications is operated (It is to be noted that angles between respective vectors are exaggerated thus different from actual ones for facilitating the understanding of the explanation). In FIG. 4B, vectors in FIG. 4A respectively corresponding to the tangential velocities of the magnetic heads 6a to 6d, the running velocity of the tape, and the relative velocities therebetween when the apparatus operates in the respective modes are shown as a table.
In FIG. 4A, the broken line OP represents the direction of tape running, vector OC represents a tangential velocity (rotational speed is 2000 r.p.m.) in the standard mode, where the magnetic tape runs at the standard speed of the magnetic heads 1a and 1b in the conventional apparatus shown in FIG. 1, and vector CE represents a running velocity of the tape 3 in the standard mode in the same apparatus. At this time, a resultant vector OE from the vector OC and the vector CE represents a relative velocity between the magnetic head 1a or 1b and the tape 3. And an angle (∠EOP) defined by the vector OE and the tape running direction OP the standard track angle θ of 6°22'59.5" which must be observed all the time as well as the standard track length L. Accordingly, an angle (∠COP) defined by the vector OC and the vector OP corresponds to a lead angle of the tape 3 in FIG. 1. This angle becomes equal to 6°22' as previously described as the standard lead angle.
The vector OF represents a tangential velocity of the magnetic head 6a, etc. in the case of carrying out recording/playback at the standard tape speed using the apparatus of FIG. 3 which is modified from the conventional apparatus, and the revolutional speed of the rotary drum 5 in this case is modified to 1000 r.p.m., wherein ∠FOP represents a lead angle of the tape 3 in FIG. 3, which becomes equal to 6°21'0.82" as described before. Since the running velocity FG of the tape 3 in this case is equal to the standard one (CE=FG), relative velocity between the magnetic head 6a, etc. and the tape 3, which is represented by vector OG, is directed in the same direction as that of the vector OE, and its magnitude becomes equal to one half thereof but the standard track angle θ which is equal to the angle ∠EOP and the standard track length L are still observed. On the other hand, the time required until, e.g., the magnetic head 6a rotates in R-direction by an angle of 90 degrees to scan one track on the tape 3 becomes equal to 15 msec, which is two times as much as the conventional one.
In FIG. 3, when it is assumed that, the magnetic head 6a rotates by an angle of 90 degrees to effect a scanning on the tape 3 at a time period of 15 msec at the time of recording to form one track to conduct a recording, the magnetic head 6b will begin scanning on the tape at the time when the scanning of the magnetic head 6a is completed to form a next track to conduct a recording. At times subsequent thereto, when digital signals are recorded for a time period during which scanning on the tape 3 is sequentially conducted in the same manner as stated before, tracks similar to those in FIG. 2 are formed on the tape 3. Namely, the recording tape 3 based on the DAT format is obtained.
At the time of playback, by using the magnetic heads 6a to 6d as the playback heads to sequentially conduct a scanning of respective tracks on the tape 3 in a manner similar to the above, it is possible to read the digital signals recorded thereon.
As just described above, the apparatus of the first embodiment has an arrangement such that four magnetic heads 6a to 6d are provided, and that the rotary drum 5 is rotated at 1000 r.p.m. during recording/playback, thus allowing any one of magnetic heads 6a to 6d to stay on the tape 3 for scanning at all times. Thus, the blank time between scanning operations encountered with the conventional apparatus does not occur. In relation to this, since it is possible to allow the time required for scanning one track by four magnetic heads 6a to 6d to be a value two times as much as the conventional one, recording/playback can be advantageously conducted with the data bit rate therefor being one half.
An actual example for carrying out times four high-speed dubbing using the apparatus of FIG. 3 will now be described. The recording operation and the playback operation will be similarly explained. In FIG. 4A, vector AB represents a running velocity of the tape 3 at the time of times four speed dubbing, and is parallel to the vector CE and has a magnitude four times larger than the standard speed. The rotary drum 5 is rotated at 4000 r.p.m., and the tangential velocity of the magnetic heads 6a to 6d at that time is represented by vector OA. Thus, the relative velocity between the magnetic heads 6a to 6d and the tape 3 is represented by OB, and has a magnitude four times that of the vector OG in the standard mode of this embodiment. When compared with the relative velocity OE in the standard mode of the conventional apparatus, it has a magnitude two times as much as that, and an angle ∠BOP agrees to the angle ∠EOP thus the standard track angle θ and the standard track length L are observed.
FIG. 5 is a block diagram showing a recording/playback circuit when the rotary drum 5, etc. of FIG. 3 is used. This circuit includes changeover switches 7a to 7d for connecting magnetic heads 6a to 6d to the recording unit or the playback unit, which effect switching operation in response to a recording/playback control signal, recording amplifiers 8a to 8d, and playback amplifiers 9a to 9d. The recording/playback circuit further includes a select switch 10 for selection of the magnetic heads 6a to 6d at the time of recording, which effects switching operation in response to a recording head select switch control signal, and a select switch 11 for selection of the magnetic heads 6a to 6d at the time of playback, which effects switching operation in response to a playback head select switch control signal.
In FIG. 5, the recording/playback circuit further includes, as the components on the recording side, a lowpass filter 18 for passing only the low frequency components of an input analog recording signal supplied to a terminal 18a, an analog/digital (A/D) converter 16 for converting an analog signal which is an output from the filter 18 to a digital signal, an encoder 14 for encoding into a desired code format the digitalized recording signal from the A/D converter 16, and a modulator 12 for modulating the coded recording signal to output it to the select switch 10. In addition, the recording/playback circuit includes, as the components on the playback side, a demodulator 13 for demodulating a signal to be reproduced from the select switch 11, a decoder 15 for decoding an output from the demodulator 13, a digital/analog (D/A) converter 17 for converting a digital signal which is a reproduced signal from the decorder 15 to an analog signal, and a low-pass filter 19 for passing only the low frequency components of the analog reproduced signal from the D/A converter 17 to a terminal 19a. Respective digitalized signal data of signals to be recorded and then reproduced are written into a RAM 20 connected to the encoder 24 and the decoder 15 before modulation and after demodulation, respectively.
The above-mentioned select switch 10 is controlled by the recording head select switch control signal. FIG. 6 is a logic circuit diagram showing an example of the control signal generator circuit for operating the select switch 10 in FIG. 5. In FIG. 6, a recording head select switch control signal generator circuit 100 comprises a frame signal input terminal 101, a channel discrimination signal input terminal 102, first and second NOT circuits 103 and 104 for inverting signals inputted from the terminals 101 and 102, respectively, a first NAND circuit 105 for providing an inversed negated logical product of both the signals input through the terminals 101 and 102, a second NAND circuit 106 for providing an inversed logical product of the frame signal inputted from the terminal 101 and an output from the second NOT circuit 104, a third NAND circuit 107 for providing an inversed logical product of an output from the first NOT circuit 103 and the discrimination signal inputted from the terminal 102, and a fourth NAND circuit 108 for providing an inversed logical product of both outputs from the NOT circuits 103 and 104. In the recording mode, the respective outputs from the first to fourth NAND circuits 105 to 108 allow changeover contacts 10a to 10d of the select switch 10 and its movable contact to be closed, thus placing the heads 6a to 6d in a recordable state. The operation of the logic circuit shown in FIG. 6 is performed on the basis of a frame signal having a period of 5 msec shown in FIG. 7(a) which is inputted to the terminal 101, a channel discrimination signal having a period of 7.5 msec shown in FIG. 7(b) which is inputted to the terminal 102, causing a recording signal shown in FIG. 7(c) supplied from the modulator 12 so as to be supplied sequentially to the heads 6a to 6d to form alternately the tracks of A and B channels depending on the above-mentioned discrimination signal. The frame signal and the discrimination signal are genestandard in the encoder 14. By inputting these two signals having different periods to the generator circuit 100, respective logic elements 105 to 108 perform predetermined logical operations to generate respective enable signals shown in FIGS. 7(d) to 7(g). For example, when the frame signal and the channel discrimination signal are both High level, only the enable signal of the switch contact 10a shifts to Low level. Thus, as shown in FIG. 5, the digitalized recording signal supplied from the modulator 12 is delivered to the head 6a through the recording amplifier 8a.
During the recording operation explained above, all of the changeover switches 7a to 7d are kept at the recording positions to connect the heads 6a to 6d to the respective recording amplifiers 8a to 8d. As explained in the foregoing, the select switch 10 is sequentially switched by the recording head select switch control signal at timings such that the contact 10a is selected when recording is conducted using the magnetic head 6a, and that the contact 10b is selected when recording is conducted using the magnetic head 6b.
FIG. 8 is a circuit diagram showing a logic circuit configuration of a control signal generator circuit 110 for controlling the select switch 11 in FIG. 5 for sequentially switching the magnetic heads 6a to 6d in the playback operation. FIG. 9 is a timing chart showing its logical operation. In FIG. 8, the signal generator circuit 110 has an arrangement corresponding to the signal generator circuit 100 shown in FIG. 6, i.e., includes a frame signal input terminal 111, a channel discrimination signal input terminal 112, first and second NOT circuits 113 and 114, and first to fourth NAND circuits 115 to 118. The fixed contacts 11a to 11d of the switch 11 are closed by outputs from these NAND circuits 115 to 118, respectively. Thus, the playback operation of the magnetic heads 6a to 6d is carried out as shown in FIG. 9 in the similar but reversed manner explained with FIG. 7 for recording.
A dubbing operation at the quadruple tape speed using a pair of identical apparatuses shown in FIG. 5 wherein one of them is operated as a playback apparatus and another is operated as a recording apparatus and their tape speed and drum rotational speed are same each other, will be explained as follows. According to the DAT format tracks are composed of a digital signal recorded on the track 4a (see FIG. 2) having a plus azimuth (which will be called "A channel"), and a digital signal recorded on the subsequentially formed track 4b having a minus azimuth adjacent to the track 4a (which will be called "B channel"), and signal processing is carried out with one frame being as a unit.
At the time of playback, for a time period during which the rotary drum 5 makes one turn, data corresponding to 2 frames are reproduced, e.g., in order of "A channel, B channel, A channel, and B channel" by the magnetic heads 6a to 6d. At this time, all of the changeover switches 7a to 7d are maintained at the playback positions to connect the heads 6a to 6d to the respective playback amplifier 9a to 9d. The select switch 11 is switched in a manner so that it is connected to the contact 11a when playback by the magnetic head 6a is conducted, and is connected to the contact 11b when playback by the magnetic head 6b is conducted. This switching is carried out by the playback head select switch control signal, one complete cycle of the switching takes 15 msec which is four times the 3.75 msec required for playback of one channel.
Accordingly, the picked up data by the magnetic heads 6a to 6d are respectively amplified by the corresponding playback amplifiers 9a to 9d, and are converted into a continuous stream of data by the select switch 11, and are demodulated by the succeeding demodulator 13. The demodulated data are stored in the RAM 20 for being decoded and error corrected subsequently by the decoder 15, then read out from the RAM 20 to be transferred to the RAM 20 of the recording apparatus of the pair through the terminal 20a.
FIG. 10 shows a dubbing timing in the case of carrying out a dubbing using the pair of identical apparatus of FIG. 5. In the playback apparatus, a digital signal is first reproduced from a prerecorded tape 3 loaded thereto, and is written to the RAM 20 thereof at a rate of one frame being as a unit. Then, this digital signal is decoded by the decoder 15 at a rate of one frame being as a unit in a manner similar to the above, and is further transferred to the RAM 20 of the recording apparatus at the same frame rate. In the recording apparatus, the digital data of the digital signal thus transferred are received at the same frame rate, and are then encoded by the encoder 14. Furthermore, the encoded digital data of one frame are recorded onto a blank tape 3 loaded into the recording apparatus. Thus, dubbing of one cycle is completed. As can be seen from FIG. 10, it takes five frames of time from reading out the recorded data of one frame to rewriting the same one the blank tape to complete the cycle. For this reason, RAMs corresponding to three frames of data are needed on each of the recording and playback apparatus, i.e. a total of 6 frames of RAMs (Of course, a single RAM with divided memory areas may be used).
The example of dubbing operation using a pair of identical apparatus having the recording/playback functions as shown in FIG. 5 has been explained in the foregoing. In addition, when there is employed a double deck type machine in which two mutually independent tape transport mechanisms, two groups of heads, and two rotary drums one of which is used exclusively for recording and the other is used exclusively for playback are arranged in one apparatus together with a necessary circuitry as in a second embodiment shown in FIG. 11, the parts designated by the same reference numerals as those in FIG. 5 are the same construction, respectively. The arrangement of this embodiment differs from the apparatus of FIG. 5 in that a group of heads 23a to 23d exclusively used for recording and another group of heads 24a to 24d exclusively used for playback are provided, respectively, and that the changeover switches 7a to 7d are omitted. The dubbing timings in the case of the apparatus constructed as shown in FIG. 11 are shown in FIG. 12. As seen in this figure, the required RAM has a memory capacity corresponding to four frames, which is reduced by the memory capacity of two frames, as compared to the case shown in FIG. 10.
While the dubbing at the quadruple tape speed has been described up to now, a dubbing at the double speed may be conducted using the apparatus of FIG. 5. In this case, as shown in FIG. 4, the running velocity of the tape 3 is represented by vector DE, the a magnitude of which is two times as much as that of the standard running velocity CE and is one half of that of the running velocity AB of the quadruple speed, wherein the direction of the velocity vector DE is the same as those of velocity vectors CE and AB. Accordingly, in that case, the tangential velocities of the heads 6a to 6d are represented by vector OD and the drum rotational speed becomes equal to 2000 r.p.m. This rotational speed is equal to one in the standard mode of the conventional apparatus.
FIG. 13 is a block diagram showing a third embodiment in which DAT is actually used as a data streamer wherein the same components as those in FIG. 5 are designated by the same reference numerals, respectively, and their explanation will be omitted. In this figure, a hard disk drive (HDD) 26, a floppy disk drive (FDD) 27, and a DAT are connected to a computer 28 through an interface circuit 25. This arrangement is used for recording data stored in the HDD 26 and the FDD 27 onto a backup tape by means of the DAT. Because recording/playback at the double or the quadruple tape speeds can be conducted in this case, it is possible to transmit and receive data to and from the computer 28, etc. at a speed higher than that in the prior art.
FIG. 14 shows a rotary drum 29 and its peripheral arrangement according to a fourth embodiment of this invention. The diameter of the rotary drum 29 in the fourth embodiment is selected to 15.039 mm, which is substantially one half of 30 mm for the rotary drum 2 of the conventional apparatus shown in FIG. 1A, or 30.077 mm for the rotary drum 5 of the apparatus according to the first embodiment of this invention shown in FIG. 3. On the rotary drum 29, two magnetic heads 30a and 30b having different azimuth angles each other are provided at an angular interval of 180 degrees.
Different from the manners shown in FIGS. 1 and 3, the tape 3 is wound onto the rotary drum 29 in an angular range of 180 degrees, and the lead angle in this case is set to 6°21'0.82" in the same manner as in the case shown in FIG. 3.
The recording and playback apparatus of the fourth embodiment is directed in its development to build a system which satisfactorily performs a dubbing at the double tape speed. Similarly to FIGS. 4A and 4B, the running velocity of the tape 3, the tangential velocity of the magnetic head 30a or 30b, and the relative velocity between the magnetic heads 30a and 30b and the tape 3 are shown as respective vector diagrams in FIGS. 15A and 15B. In FIG. 15A, vector OC represents a tangential velocity (2000 r.p.m. when the diameter of the rotary drum is 30 mm) of the magnetic head 30a or 30b in the standard mode of the conventional apparatus, and vector CE represents a running velocity (0.815 cm/sec) in the standard mode of the tape 3. Accordingly, a lead angle defined by the vectors OC and OP is equal to 6°22'.
FIG. 15B is a table collectively showing vectors in FIG. 15A corresponding to the tangential velocity of the magnetic head, the running velocity of the tape 3, and the relative velocity therebetween in the double speed mode and in the standard mode.
When an operation is conducted to rotate the rotary drum 29 at 4000 r.p.m. in the apparatus of FIG. 14, the tangential velocity of the magnetic head 30a or 30b at that time is represented by vector OD. At this time, when the tangential velocity of the tape 3 is assumed as vector DE two times larger than the vector CE, the relative velocity between the tape 3 and the magnetic head 30a or 30b is expressed as vector OE, which is in correspondence with the case in the standard mode of the conventional apparatus. Accordingly, in this case, the circuit characteristics of the magnetic heads 30a and 30b and the rotary transformer (not shown) in the rotary drum 29, etc. may be maintained same as ones for the conventional apparatus and the standard track angle θ which is equal to an angle ∠EOP and the standard track length L are observed.
In the case of carrying out recording/playback operation in the standard mode using the apparatus shown in FIG. 14, the rotary drum 29 revolves at 2000 r.p.m. At this time, the tangential velocity of the magnetic head 30a or 30b is represented by vector OF of FIG. 15A and the relative velocity with respect to the tape 3 running at a velocity expressed as vector FG is represented by vector OG. This relative velocity is equal to one half of the relative velocity between the magnetic head and the tape 3 in the standard mode of the conventional apparatus and the standard track angle θ which is equal to the angle ∠GOP and the standard track length L are observed.
FIG. 16 is a block diagram of the recording and playback apparatus using rotary drum 29, etc. shown in FIG. 14. In this figure, the same components as those in FIG. 11 are designated by the same reference numerals, respectively, and their explanation will be omitted. In accordance with the DAT format, as described before, each frame is comprised of a set of A and B channels. Accordingly, in the playback (PB) section, as shown in the timings of FIG. 17, respective operations of playback, decoding and transfer are carried out frame by frame and three frames by such complete one playback cycle. Thus, RAM having a memory capacity corresponding to three frames is required.
The double speed dubbing of a digital signal, e.g., an audio signal, etc. using a pair of two identical recording and playback apparatus according to the fourth embodiment will be now described.
In reproducing a digital signal by means of magnetic heads 30a and 30b, a time period corresponding to one revolution of the rotary drum 29 is assumed as one cycle. At this time, a changeover switch 33 is connected to a playback side contact 33b. In the case of playback for the A channel by means of the magnetic head 30a, a changeover switch 32 is connected to a fixed contact 32a. On the other hand, in the case of playback for the B channel by means of the magnetic head 30b, the changeover switch 32 is connected to a fixed contact 32b. Since it takes 7.5 msec to reproduce one channel, the changeover switch 32 is switched to the contact 32a or 32b every 7.5 msec by the head select switch control signal.
The reproduced signal is amplified by the playback amplifier 34, and is then demodulated by a demodulator circuit 35. The signal thus demodulated is written into a RAM 36. Next, the signal data transferred from the RAM 36 is subjected to decoding and error correction performed by the decoder 37, and is then transferred through a terminal 37a as digital data to the other apparatus of the pair, which performs as a recorder.
In the recorder, the changeover switch 33 is connected to a recording side contact 33a. The digital data having been transferred is through a terminal 38a first written into the RAM 36 of the recorder. A modulated digital data stored in the RAM 36 is encoded by an encoder 38, and is then modulated by a modulator 39. The digital signal of the A channel thus formed is written onto the tape 3 by means of the magnetic head 30a being amplified by the recording amplifier 40. On the other hand, a modulated digital signal of the B channel is written onto the tape 3 by means of the magnetic head 30b being amplified by the recording amplifier 40. Also in this case, recording is conducted while the changeover switch 32 is being switched by the head select switch control signal every 7.5 msec.
In this fourth embodiment, even in the case of carrying out a dubbing at the double speed, the relative velocity between the magnetic head 30a or 30b and the tape 3 is the same as that in the standard mode, and the diameter of the rotary drum 29 is reduced to about one half of that of the conventional apparatus, resulting in the advantage that the entirety of the apparatus including mounting components for the drum can be small-sized and lightweight.
The recording and playback apparatus of this embodiment constructed as stated has following advantages. Even in the case of carrying out recording/playback at the quadruple tape speed, by arranging such that the diameter of the rotary drum is equal to, e.g., 30.077 mm and the lead angle is equal to, e.g., 6°21'0.82", there may be adopted a rotational speed of the rotary drum equal to 4000 r.p.m. which is twice as much as that of the prior art. Accordingly, a stable operation of the running system is assured. The aforementioned double rotational speed of the drum may be realized only by allowing the rotary transformer and/or the magnetic head to have a frequency characteristic extended twice as wide as the conventional one, and by allowing the operating speeds for the demodulation of a reproduced signal and writing into the RAM in the playback system, and reading from the RAM and the modulation in the recording system to be twice as high as the conventional ones. Thus, even in the case of using DAT as a data streamer, data can be transferred from the computer, etc. at a higher speed than normal. Moreover, in the case of carrying out recording/playback at the double tape speed using the rotary drum constructed above, it is sufficient that the rotational speed of the rotary drum be equal to 2000 r.p.m. At this time, the relative velocity between the magnetic tape and the magnetic head becomes the standard relative velocity. Because the frequency characteristics and the operating speeds are the same as those in the conventional apparatus, conventional components may be used for the rotary transformer, the magnetic heads, the modulator/demodulator circuits and the like.
Further advantages with this embodiment are as follows. By employing an arrangement in which the diameter of the rotary drum is selected to, e.g., 15.039 m, the lead angle is selected to, e.g., 6°21'0.82", and the magnetic tape is wound in an angular range of 180 degrees, when recording/playback at the double tape speed is conducted, the rotary drum's rotational speed becomes equal to 4000 r.p.m. and the relative velocity between the magnetic tape and the magnetic head becomes the standard relative velocity. Accordingly, the frequency characteristics of the magnetic head and the rotary transformer, the modulation/demodulation operating speeds, the operating speeds for writing/reading into and from the RAM, and the like may be maintained same as those in the conventional apparatus, and the diameter of the rotary drum may be about one half of the one for the conventional apparatus, resulting in the advantage that the apparatus can be compact and lightweight. | A digital signal recording and playback apparatus having a rotary heads mounted on a rotary drum capable of recording/reproducing a digital signal onto/from a magnetic tape at a tape speed which is N times as much as the standard speed while conforming to the standard track angle and length. The number of the rotary heads are increased from the standard two heads whereas the drum speed is made one half of N times standard speed and the drum diameter is made slightly larger from the standard so that the relative speed between the running tape and the rotating heads becomes equal to the standard in the double tape speed mode, and becomes twice that in the quadruple tape speed mode. Alternatively, the tape is wound around the drum having two heads, over the angular range of 180 degrees instead of the standard 90 degrees, the drum diameter is made smaller than the standard, and the drum speed is N times the standard so that the relative speed of the heads becomes equal to the standard in the double tape speed mode. | 6 |
[0001] This utility application is a division of U.S. patent application Ser. No. 10/423,532, filed on Aug. 11, 2003 and currently pending, which claims priority to U.S. Provisional Patent Application No. 60/377,509, filed on May 1, 2002, both of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to carwashes and, more particularly, to modular prefabricated carwashes that may be easily transported to a desired site complete with equipment installed and tested.
[0004] 2. Description of the Related Art
[0005] Many people have become accustomed to the convenience of using a carwash. Carwashes are frequently installed at gas stations whereby drivers can purchase gas and at the same time purchase a carwash. For the drivers, the combination of getting gas and a carwash at the same location is a great convenience. For the owners of the gas stations or convenience stores, the carwash presents an additional opportunity to increase sales and revenue. From a competitive aspect, many gas stations and convenience stores want a carwash in order to lure additional customers to their stores.
[0006] The construction of carwashes normally requires expertise in several different areas. After a suitable location has been secured, the floor plan of the building must be laid and the car washing equipment position determined. The building generally consists of a tunnel in which the car washing equipment is located and where the car is washed and a mechanical room where the controls for the equipment are kept. The distribution and delivery of power and supplies to such equipment must then be designed. Since each car wash building may be slightly different, each layout for the equipment is also slightly different, and the design of a system for the distribution and delivery of supplies for the equipment previously required individual attention for each carwash. The design and installation of such a system requires considerable expertise in the areas of plumbing, electricity and hydraulics. Skilled plumbers and electricians employed in the construction must also be specifically experienced in carwash equipment.
[0007] Before the present invention, the building of a carwash in a remote location required a considerable expenditure of time and effort. It was required that the builder travel to the location in order to contract skilled electricians, plumbers, and equipment installation personnel in order to ensure their availability as necessary for the installation.
[0008] Once these experienced technicians had been scheduled, it was required that they design, and subsequently install chemical, electrical and hydraulic distribution systems to deliver supplies to the equipment to be used in the carwash. This required a large expenditure of time and concerted effort by these skilled technicians, resulting in a high cost to the builder.
[0009] After installation of the equipment and supply distribution and delivery systems, these systems were subject to inspection and approval by local officials. In view of the fact that the systems were designed and built specifically for the single carwash in which they were located, these inspections were often rigorous. Occasionally parts of the systems might need to be replaced in order to meet municipal codes. Additionally, the entire design and installation would have to be supervised by representatives of the builder in order to ensure the system met the builder's standards.
[0010] Other problems with prior art carwash supply distribution systems include a difficulty in servicing defective or worn out parts such as valves or solenoids because they may be permanently installed as parts of the plumbing. Additionally these valves or solenoids may be located in the carwash tunnel, increasing the deleterious exposure to chemicals and water used in the car washing process.
[0011] The plumbing, hydraulic and electrical lines for conventional carwashes normally require that they be secured to the walls of the carwash tunnel for support. This greatly hinders the task of cleaning the walls of the tunnel. Dirt and grime are thus more likely to accumulate and associated problems arise within the carwash tunnel.
[0012] If the supplies of chemicals are also located in the carwash tunnel, the tunnel itself might need to be heated, as some of the chemicals would suffer adverse effects from low temperatures. If this were the case an additional problem arises since the viscosity of the concentrated chemicals to be used in the carwash increases substantially at low temperatures. This causes problems in the dilution and mixing of the chemicals.
[0013] Oftentimes, a carwash can be installed on-site in approximately three months. During this time, the owner of the carwash will contact with a general contractor who oversees construction of the carwash. The general contractor coordinates and schedules the various laborers involved in constructing the carwash. During a first phase, the necessary groundwork is performed, including laying the concrete and running a drainage pipe to a sewer system. Constructing the carwash involves erecting the walls of the tunnel and also constructing the equipment room with suitable access to the outside. The washing unit itself is then installed within the tunnel. This washing unit may comprise an overhead gantry system in which case the washing unit is placed upon a set of support beams. The washing unit may comprise other types of units, such as a floor-mounted gantry system.
[0014] During the construction of a prior art carwash, plumbers are needed for the running of the drainage pipe, connecting the carwash to a water supply, and for the various interconnection within the carwash itself. Electricians are also needed for the power and control wiring. Carpenters or other such laborers are needed to erect the walls and ceilings of the buildings and additional laborers needed for doing the necessary ground preparation work, laying the concrete, and perhaps for erecting an exterior elevation, such as bricks or stucco.
[0015] Thus, as can be appreciated by those skilled in the art, the construction of a carwash requires the careful coordination of a large number of skilled craftspersons. Because the construction of a carwash requires the assistance of so many people, the failure of any particular person or group of people to satisfactorily perform their tasks can have deleterious effects on the carwash. Oftentimes, problems arise during the construction of the carwash and the general contractor is forced to determine which sub-contractor is at fault, with the sub-contractors typically accusing each other of the problems in the construction of the carwash. Also, the laborers may not have experience in constructing a carwash and, as a result, the quality of their work may be sub-standard. For example, an electrician may have experience with power distribution but may not have sufficient experience with control wiring within a carwash to do a quality job on a that portion of the job. In light of all these variables in the workforce, the quality and installation of carwashes across the country is not uniform.
[0016] In addition to dealing with likely problems or obstacles in the construction of the carwash, the future owner of the carwash must also endure long delays before the carwash is operational. The typical time for constructing a carwash is on the order of three months. During this time, the future owner must cope with the nuisance of having a worksite on its premises, which could interfere with the ability to carry on normal operations at the business. This long delay also presents a financial burden to the future owner because of the financial resources tied up in the construction and the wait of three or so months before the carwash can generate any revenue. Thus, the future owner of the carwash has a great incentive to expedite construction of the carwash, not only to minimize the nuisance but also to expedite when the carwash can begin to generate revenue.
[0017] This pressure to expedite construction, however, may unnecessarily hasten work on the carwash and cause the laborers to sacrifice quality in order to meet shortened deadlines. The future carwash owner must perform a careful balancing between pushing the general contractor and sub-contractors to finish the job with the desire to have a quality constructed carwash. Any sacrifice in the quality may only cause the carwash owner to incur greater repairs down the road and an additional nuisance and expense associated with those repairs.
[0018] Some attempts have been made to simplify the construction of a carwash. For example, some carwash owners, especially gas stations, have a standard design for the carwash. The carwashes therefore may have the same dimensions, the same walls and ceilings, and same equipment installed within the carwash. By adopting a single design, the installation and construction of a carwash can become more routine and thus less prone to unforeseen problems. Another approach is to prepare assemblies of components which are then installed within the carwash structure. For instance, U.S. Pat. No. 4,955,405 describes a “Prefabricated Car Wash Distribution And Delivery System And Method” wherein a raceway is prefabricated with lines and hoses and this assembly is transported to the car wash for installation. By fabricating the raceway as a preassembled structure, the work that is needed on site for making the necessary interconnections and wiring between the equipment is reduced. While this patent addresses some of the problems mentioned above, the construction of a carwash still requires the assistance of various skilled laborers, including electricians and plumbers.
[0019] A need exists for systems and methods for constructing carwashes that address the above-mentioned problems. For example, a need exists for systems and methods for constructing a carwash that is consistently constructed according to high quality standards and can be installed in a minimal amount of time. As mentioned above, these two desires run counter to each other since hastening the construction of a carwash often results in sacrificing quality.
SUMMARY OF THE INVENTION
[0020] An object of the present invention is to provide a modular carwash for simple construction on site.
[0021] A further object of the present invention is to provide a prefabricated modular carwash assembly to reduce the number of technicians required for installation at a carwash location.
[0022] Yet a further object of the present invention is to provide a fully assembled modular carwash that can be constructed in a short period of time.
[0023] The modular carwash assembly of the present invention is modular in design such that it may be transported to any desired location.
[0024] The modular carwash assembly of the present invention includes a carwash module and an equipment module that are easily installed at a work site. Alternatively these components may be erected at a predetermined location and transported to the building site. In either case, the carwash module and equipment module are easily constructed and easily connected to each other.
[0025] The carwash module includes a skeletal system secured on a sloped flooring, wherein the skeletal system is able to support the carwash equipment. The skeletal system includes a series of columns, with pairs of columns being connected by crossarms. The skeletal system thereby is able to support a carriage that is supported on two carriage rails mounted between two crossarms. The carriage supports a pair of spray arms that direct water and cleaning fluid towards a vehicle positioned within the carwash module.
[0026] The equipment module is constructed in substantially the same manner as the carwash module, with the equipment module being positioned proximate the carwash module at the building site. The equipment module includes washing and drying components such as a pumping station for delivering water and fluid to the spray arms and an air compressor for generating a stream of air to dry the vehicle after washing. Additionally, the equipment module may include water purifiers, water softeners and related equipment.
[0027] The equipment module is therefore designed to be easily connected to the carwash module. More specifically, the carwash equipment mounted in the carwash module is easily connected with the carwash equipment housed in the equipment module, such that the connections can be completed in a quick fashion without requiring the work of plumbers, electricians, and other specialists.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] A modular carwash embodying the features of the present invention is depicted in the accompanying drawing which form a portion of this disclosure and wherein:
[0029] FIG. 1A is a front end view of the modular carwash assembly of the present invention;
[0030] FIG. 1B is a rear end view of the modular carwash assembly of the present invention;
[0031] FIG. 1C is a first side view of the modular carwash assembly of the present invention;
[0032] FIG. 1D is a second side view of the modular carwash assembly of the present invention;
[0033] FIG. 2 is a top plan view of the modular carwash assembly of the present invention;
[0034] FIG. 3 is a sectional top view of the modular carwash assembly of the present invention as illustrated in FIG. 2 ;
[0035] FIG. 4 is a schematic view of the modular carwash assembly of the present invention as illustrated in FIG. 3 ;
[0036] FIG. 5 is a partially exploded view of the carwash equipment used in the modular carwash assembly of the present invention;
[0037] FIG. 6 is a top plan view of the carwash equipment attached to the building skeleton;
[0038] FIG. 7 is an end view of the modular carwash assembly of the present invention;
[0039] FIG. 8A is a sectional view of the first side of the modular carwash assembly;
[0040] FIG. 8B is a sectional view of the second side of the modular carwash assembly; and
[0041] FIG. 9 is a sectional view of the flooring of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0042] Reference will now be made in detail to preferred embodiments of the invention, non-limiting examples of which are illustrated in accompanying FIGS. 1 through 9 . These figures illustrate just one example as to how a carwash assembly 10 according to a preferred embodiment of the present invention may be manufactured. Elevations may be customized for a location (brick, stucco, ACM and split face block) rooflines also. It should be understood that the drawings do not limit the invention to the precise embodiment disclosed; rather, carwashes according to the invention may have other dimensions or made of other materials.
[0000] Overview
[0043] Systems and methods according to preferred embodiments of the present invention address the problems mentioned in the Background section of this application by providing a modular carwash assembly 10 that may be constructed in an expedited manner and prefabricated to be shipped to a desired location. In particular, the modular carwash assembly 10 of the present invention includes a carwash module 12 and an equipment module 13 , wherein the carwash equipment 30 is installed in both modules 12 , 13 . The carwash module 12 includes a series of walls 14 , a ceiling 16 , and a sloping floor 18 . By prefabricating the entire carwash assembly 10 or substantially all of the carwash assembly 10 , both the carwash module 12 and the equipment module 13 can be transported to the site for the establishment of the carwash assembly 10 , installed, and ready to use in a minimal amount of time. For example, in contrast to the typical construction cycle of three months or more, the modular carwash assembly 10 can be installed on the building site and ready to use in as little as one or two days. Further advantages and benefits of the carwash assembly 10 according to the present invention will be apparent from the description below.
[0000] Structure
[0044] Significantly, the carwash module 12 and equipment module 13 of the modular carwash assembly 10 are such that they can be shipped either with all of the necessary carwash equipment 30 installed or the various components of the modules 12 , 13 can be transported to the building site and the carwash equipment 30 then installed. An important feature of the carwash module 12 is that the walls 14 of the carwash assembly 10 are constructed with sufficient strength to support the weight of the carwash equipment 30 . By mounting a portion of the carwash equipment 30 directly to the walls 14 of the carwash module 12 , the carwash assembly 10 according to the invention avoids the need for additional support beams or other similar structure for supporting the weight of overhead washing units.
[0045] In the preferred embodiment, both modules 12 , 13 include a skeletal system 20 , which will include a series of columns, advantageously steel columns, 22 and crossarms, advantageously steel crossarms, 24 . With the carwash module 12 , the inner surface of the columns 22 advantageously are engaged by an impervious protective layer 26 , while the outer surface of the steel columns 22 are engaged by an exterior layer 28 . This skeletal system 20 can therefore reduce the width of the carwash assembly 10 as compared to conventional carwashes, and more importantly can reduce the height of the carwash assembly 10 . With conventional carwash designs, the walls are made of metal paneling and must be constructed high enough so that the overhead washing unit and support structure can be received within the carwash. In doing so, the conventional carwash cannot have its structure prefabricated since the height of the carwash is too high to pass underneath bridges during transit on the highway. In contrast, the carwash assembly 10 according to the preferred embodiment of the present invention enables the carwash module 12 to be prefabricated and shipped preassembled to the desired site for placement, and to be within such height restrictions.
[0046] Another advantage of the carwash assembly 10 according to preferred embodiments of the present invention results from the use of the impervious protective layer 26 , which surrounds a tunnel 25 . During the fabrication of the carwash module 12 , the protective layer 26 is connected with the skeletal system 20 to form the tunnel 25 of the carwash assembly 10 . The protective layer 26 will thereby protect the carwash module 12 from the corrosive environment created during use of the carwash assembly 10 . This corrosive environment is created through the use of the various chemicals used and applied to the vehicle being cleaned as well as to the ambient environmental conditions. The protective layer 26 is preferably impervious to these chemicals and to the exposure to environmental conditions to protect the skeletal system 20 . Some examples of suitable impervious protective layers 22 include fiberglass, polyurethane or like coating, which may be applied within the tunnel 25 . It should be noted that the protective layer 26 may be sprayed onto an interior of the tunnel 25 .
[0047] The ceiling 16 of the carwash assembly 10 according to a preferred embodiment of the invention can accommodate any suitable elevation to allow the desired vehicular traffic through the carwash module 12 . Moreover, the exterior layer 28 can be formed of a variety of desired materials, such as thin set brick, panels, stucco, and so forth, as well as any desired shape, such as a gabled roof, flat roof, windows, and the like. Thus, carwashes 10 according to the preferred embodiment of the invention are not limited in any set of dimensions, but may be compacted in size as needed for a particular location.
[0000] Carwash Equipment
[0048] Looking to FIGS. 5 and 6 , the carwash equipment 30 is housed in both the carwash module 12 and the equipment module 13 . The preferred embodiment of the carwash equipment 30 will include a carriage 32 that is mounted on a pair of carriage rails 34 using a set of carriage wheels 33 . The carriage wheels 33 are thereby driven by a carriage motor (not illustrated) for the carriage 32 to traverse the carwash tunnel 25 . At least one spray arm 36 is rotatably connected to the carriage 32 such that each spray arm 36 may swivel about the vehicle positioned in the tunnel 25 . The spray arm 36 is connected to a fluid pumping station 38 located in the equipment module 13 via a spray conduit 40 . As a result, water is provided for soaking the vehicle. The fluid pumping stating 38 is housed in the equipment module 13 , such that the spray conduit 40 is used to connect between the carwash module 12 and the equipment module 13 .
[0049] In addition to the fluid pumping station 38 , other components of the carwash equipment 30 are protectively stored in the equipment module 13 . For example, a motor control unit 44 is stored in the equipment module 13 and connected to the carriage 32 to control transverse movement of the carriage 32 within the carwash module 12 . Additionally, the carwash assembly 10 includes means for drying the vehicle after it has been washed. The drying means may include an air compressor 42 that is stored in the equipment module 13 and connected to air vents 44 in the carwash module 12 via an air conduit. As a result, a stream of air is generated to be directed toward to the center of the carwash module 12 toward the vehicle to force water from the vehicle.
[0050] In addition to these components, the carwash assembly 10 may include various accessories to aid in cleaning vehicles. Some accessories are to be secured and used within the carwash module 12 . Such accessories may include a “photoeye” (not illustrated) for monitoring the vehicle in the tunnel 25 of the carwash module 12 or a directional sign (not illustrated) mounted proximate the carriage 32 to assist persons driving their vehicle into the tunnel 25 . In addition, there may be an operational interface (not illustrated) positioned at the entrance of the tunnel 25 to assist the user. Further accessories may be positioned in the equipment module 12 , such as a water purifier or softener (not illustrated).
[0051] One embodiment of the modular carwash assembly 10 as disclosed herein is fabricated to the inventors' specifications and uses carwash equipment 30 in the tunnel 25 according to the inventors' specification. However, it should be understood that carwash assemblies 10 according to the present invention are not limited to any manufacturer nor are they limited to the precise type of carwash equipment. For example, with regard to the carwash equipment 30 , the carwash assembly 10 may comprise a full service tunnel, self-serve, in-dash bay automatic, or fleet/truck wash configuration. Moreover, the carwash equipment 30 may include a touchless washing system or a frictional engagement washing system (e.g., using a cloth brush or nylon bristles) for cleaning vehicles.
[0000] Construction of the Carwash Assembly
[0052] The carwash module 12 and the equipment module 13 of the present invention advantageously are constructed using the various components at a predetermined site and then delivered to the proper location. By producing the modules 12 , 13 prior to delivery, the construction on the desired site can be prompt. Looking at FIGS. 7 and 9 , the carwash module 12 is advantageously manufactured by first forming a layer 19 a, advantageously of lightweight concrete, above a frame 19 b (such as an intermediate rib decking) so as to create a sloping floor 18 . The various columns 22 of the skeletal system 20 are set in the layer 19 a, if layer 19 a is concrete, while the concrete hardens. Advantageously layer 19 a is angled such that the water will drain to a central location, at which place a grate 21 is placed for the drain. A series of crossarms 24 are used to connect opposing columns 22 , on top of which is affixed a roof decking 46 .
[0053] At least two of the crossarms 24 are mounted on the columns 22 at opposed ends of the carwash module 12 . Connected between these two crossarms 24 are two carriage rails 34 . The carriage rails 34 support the carriage 32 on carriage wheels 33 rotatably connected to the carriage 32 and driven by the carriage motor. As a result, the carriage motor drives the carriage 32 longitudinally on the carriage rails 34 for the carriage 32 to traverse the tunnel of the carwash module 12 .
[0000] Operation of the Carwash Assembly
[0054] As discussed above, the carwash assembly 10 is separated into the equipment module 13 containing a substantial portion of the carwash equipment 30 and the carwash module 12 which forms the tunnel 25 for receiving the vehicle to be cleaned. Both modules 12 , 13 are preferably prefabricated for use together, and these two modules 12 , 13 are placed next to each other and coupled together at the construction site. Coupling the two structures 12 , 13 together is simple and can be performed in a short period of time relative to the construction of conventional carwash assemblies. While the invention has been shown and described as having two modules or structures, it should be understood that the carwash assembly 10 according to an embodiment of the invention may be formed as one structure or may be formed of more than two structures. For instance, for carwashes having longer tunnels, it is possible that the tunnel portion 27 of the carwash module 12 may be formed using two or more carwash modules 12 coupled together at the site. Two or more modules 12 may also be coupled together in a manner to form multiple bays.
[0055] The drawings show a carwash assembly 10 having a superstructure 20 formed with columns, preferably steel columns, 22 . These columns 22 form part of a skeletal system 20 that is capable of supporting carwash equipment and other equipment within the tunnel structure 14 . In addition to the skeletal system 20 , the carwash is also equipped with mounting hardware for enabling the carwash equipment 30 to be mounted to the skeletal system 20 . This mounting hardware can take any form. One example provides a series of brackets that are mounted to the walls 14 and to the skeletal system 20 within the walls 14 to support the rails 34 and crossarms 24 .
[0056] The walls 14 advantageously include protective layer 26 , which in this example is shown as fiberglass insulation. While fiberglass is one example of a protective layer, other embodiments of protective layers 26 may be used. Also, while the skeletal system 20 of the preferred embodiment provides the strength necessary to support the carwash equipment 30 through the use of columns 22 , other types of supports may be used, as well as other arrangements of supports, and other materials.
[0057] Thus, although there have been described particular embodiments of the present invention of a new and useful Prefabricated Modular Carwash Assembly, it is not intended that such references be construed as limitations upon the scope of this invention except as set forth in the following claims. | A method for assembling a prefabricated modular carwash assembly, including a carwash module and an equipment module, and transporting the assembly to a predetermined building site includes the fabrication of the carwash and equipment modules at an origin and transporting those modules to a desired location. The carwash module includes a skeletal system secured on a flooring, wherein the skeletal system supports the carwash equipment. The equipment module is constructed like the carwash module, and is positioned proximate the carwash module at the building site. The equipment module includes washing and drying components such as a water pumping station and an air compressor for generating a stream of air to dry the vehicle. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to electronic scanning devices, and, more particularly, to a system and method for manipulating regions in a scanned image.
2. Related Art
Scanning devices are useful in many applications where it is desirable to transfer an image from printed form into electronic form. Scanners capable of reading and converting a page into electronic format have been available for quite some time. Typically, a scanner will electronically read a page, classify the different types of images on the page and electronically store the information for later presentation and use. The types of classifications of a scanned page typically include text, photographs, drawings, charts, tables, business graphics, equations, handwriting, logos, etc. These different parts of a scanned image are typically classified into regions by a user after the scanner has scanned the page. Some scanners are capable of determining the classifications of particular regions of a scanned page in accordance with predetermined instructions.
For example, in a page including text and drawings, some scanners will scan the page and will classify and store the text information as a text region and will classify and store the drawing information as a drawing region, and so on. Unfortunately, it is possible for the scanner to interpret some regions in a manner different from that which a user desires. Multiple interpretations of the same scanned information are possible regarding the attributes of a scanned image that should be presented to a user. For example, a scanner, or more properly the scanner analysis code, might classify a particular section of text (e.g., a large capitalized first letter of a paragraph) as drawing information, or as another example, the scanner analysis code must determine whether text over a colored background should be presented as text or as part of a bitmap that includes all of the background pixels. These predefined classifications may be acceptable for some users of the scanner, but other users may wish to have the ability to alter, or adjust, the sensitivity of the scanner for each classified region type, or alter the manner in which the regions are grouped, or clustered.
For example, one user might wish only to scan a page for the purposes of entering the information on that page into a word processing document with no further manipulation desired. A different user may wish to scan the same page for the purposes of manipulating the information on the page in a more sophisticated manner.
Furthermore, once a region or set of regions are analyzed and interpreted by the scanner in a particular format and presented to a user, the regions are typically non adjustable.
Generally, there are four principal classes of regions.
1. “Primitive” vs. “Composite”
A primitive region is the simplest possible representation of a region. For text, therefore, a primitive is a single word. For a table a primitive is a single cell. For a business graphic a primitive is a single graphic element or a single textual element.
A composite region is comprised of two or more region primitives. For example, a text paragraph is itself comprised of text line composites, which are comprised of text word primitives. Tables are comprised of their cell, horizontal rule, vertical rule, column and row primitives. Charts, graphs and equations are comprised of combinations of text, mathematical character, rule and drawing primitives. Boxes and cartoons are comprised of drawing, text and/or handwriting primitives.
2. “Enclosed” vs. “Containing”
An “enclosed” region is a region whose entire set of pixels fall within the boundary of another “containing” region. Important examples of enclosed/containing region combinations include text, photographs, etc., that are within containing boxes; cells within tables that have containing rules; regular or “inverse” (i.e., lighter) text over a photograph or drawing; text on business graphics; and text over shaded (often uniformly shaded, or highlighted) backgrounds.
3. “Foreground” vs. “Background”
A “foreground” region is a region intended to convey information such as text, photographs, drawings, equations, handwriting, tables, graphics, etc. A “background” region is not intended to convey information, but often intended to provide segmentation of a document or isolation of one segment of a document from another. Background regions also include such elements as the scanner lid (which may be white, black or gray); the lid of an automated document feeder, which may include non-uniform areas; and “fringing” patterns caused by the edge of the scanbed and by the three dimensional aspects of the scanned document (e.g., the sides of pages of a book that is being scanned).
4. “Hidden” vs. “Visible”
“Hidden” regions are regions that have been identified by the document analysis code but are not presented to a user. Examples include obvious “junk” regions on the document such as page folds, staple marks, punch holes and blotches; background regions that are assumed to be less important to the user than the overlying regions (e.g., text or photographs); and regions corresponding to the scanning process (e.g., the fringes along the edge of the scanner, the scanner lid, or the automatic document feeder footprint). “Visible” regions are the set of regions identified by the analysis code that are presented to the user.
These regions are presented to a user by an automated document processing (page analysis code) system contained within the scanner software and typically presented to the user during a “scan preview” operation. During scan preview the user views on a display the image that will be scanned. The information viewed includes the region types and the information contained within each region. In the past a user of a scanner has been unable to alter the information contained within each region or the format of the presentation of the regions.
SUMMARY OF THE INVENTION
The invention provides a system and method for manipulating the regions of a scanned image. The invention allows a user of a scanner to, in real time, alter or modify the contents of each scanned region by adjusting the sensitivity of the attribute contained within the region, and furthermore, allows the user to alter the grouping of the regions presented. Although not limited to these particular applications, the system and method for manipulating regions in a scanned image are particularly suited for manipulating information pertaining to scanned information. Other applications may include manipulating documents from a digital database/file system or from other digital capture devices, such as video capture systems and digital cameras.
Architecturally, the present invention can be conceptualized as a system for manipulating region information generated by a scanner comprising a document analysis software component and a user interface in communication with the document analysis software component.
In a preferred embodiment the invention allows the user of a scanner to both manipulate information pertaining to a particular region of a scanned image, and to manipulate the regions themselves.
The present invention may also be conceptualized as providing a method for manipulating region information generated by a scanner comprising the following steps. First, an image comprising at least one region is scanned. Then, a document analysis software package analyzes the scanned image. The analysis code assigns attributes to the regions and groups the regions according to a predetermined instruction. The sensitivity of each scanned region and the grouping of the regions are manipulated using a user interface in communication with the document analysis software.
The invention has numerous advantages, a few which are delineated, hereafter, as merely examples.
An advantage of the invention is that it provides to a user significantly enhanced control over a scanned image.
Another advantage of the invention is that it allows the user of a scanner the ability to manipulate (regroup) the scanned document according to preferences of the particular user.
Another advantage of the invention is that it allows the development of a wide range of user adjustable scanner options.
Another advantage of the invention is that allows simple user interaction with a list of regions created by a document analysis package, thus increasing the user task flexibility and accuracy of the analysis code.
Another advantage of the invention is that it allows region grouping information to be stored with the regions, thus eliminating the need to rerun the document analysis package with user specified changes.
Another advantage of the invention is that it does not prevent any specific region types from being “autofound” by the analysis code package.
Another advantage of the invention is the improvement in speed realized by eliminating the requirement of reanalyzing the entire scanbed each time that region information is recalculated.
Another advantage of the invention is that it permits the selective retention, by a user, of automated regions that are represented as desired, while allowing the user to selectively alter those regions that a user wishes to manipulate.
Another advantage of the invention is that the motif will match the user expectations for “realtime updating” of the regions.
Another advantage of the invention is that it is simple in design and easily implemented on a mass scale for commercial production.
Other features and advantages of the invention will become apparent to one with skill in the art upon examination of the following drawings and detailed description. These additional features and advantages are intended to be included herein within the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention, as defined in the claims, can be better understood with reference to the following drawings. The components within the drawings are not necessarily to scale relative to each other, emphasis instead being placed upon clearly illustrating the principles of the present invention.
FIG. 1 is a schematic view of an exemplary scanner and computer system in which the logic of the present invention resides;
FIG. 2 is a schematic view illustrating the user interface and analysis code of FIG. 1 in which the logic of the present invention resides;
FIG. 3 is a flow diagram illustrating the operation of the scanned region type sensitivity logic of FIGS. 1 and 2;
FIGS. 4A-4N collectively illustrate the results obtained through the operation of the scanned region type sensitivity logic of FIGS. 1, 2 and 3 ;
FIG. 5 is a flow diagram illustrating the operation of the scanned region clustering/declustering logic of FIGS. 1 and 2; and
FIGS. 6A-6E collectively illustrate the results obtained through the operation of the scanned region clustering/declustering logic of FIGS. 1, 2 and 5 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The scanned region type sensitivity logic and the scanned region clustering/declustering logic of the present invention can be implemented in software, hardware, or a combination thereof. In a preferred embodiment, the scanned region type sensitivity logic and the scanned region clustering/declustering logic are implemented in software that is stored in a memory and that is executed by a suitable microprocessor (uP) situated in a computing device. However, the scanned region type sensitivity software and the scanned region clustering/declustering software, which comprise an ordered listing of executable instructions for implementing logical functions, can be embodied in any computerreadable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions.
In the context of this document, a “computer-readable medium” can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable medium can be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium. More specific examples (a nonexhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic) having one or more wires, a portable computer diskette (magnetic), a random access memory (RAM) (magnetic), a read-only memory (ROM) (magnetic), an erasable programmable read-only memory (EPROM or Flash memory) (magnetic), an optical fiber (optical), and a portable compact disc read-only memory (CDROM) (optical). Note that the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.
Moreover, while the scanned region type sensitivity logic will be illustrated hereafter with respect to adjusting the sensitivity of text, the scanned region type sensitivity logic is useful for adjusting the sensitivity of many other attributes of a scanned image, for example but not limited to drawings, photographs, equations, graphics, etc. Furthermore, the scanned region clustering/declustering logic will be illustrated with respect to drawings and large text, however it is applicable to all regions generated in a scanned image.
Turning now to FIG. 1, shown is a schematic view of a scanner and computer system 100 in which the scanned region type sensitivity and scanned region clustering/declustering logic of the present invention reside.
Illustratively, scanner 11 scans a document placed therein in cooperation with computer 12 . Computer 12 can be any general purpose computer that is capable of connecting to and executing the software that enables scanner 11 to function. Illustratively, computer 12 is a personal computer; however computer 12 may be any computer capable of communicating with scanner 11 . A scanned image is captured by data capture block 14 located within computer 12 . The scanned image data is illustratively stored in random access memory (RAM) 16 . RAM 16 communicates with analysis code 17 , user interface 13 , and microprocessor (uP) 25 over bus 24 .
Analysis code 17 is illustratively the logic that operates in conjunction with scanner 11 to determine the region types, locations and statistics of the scanned image that is stored as captured data in RAM 16 .
As stated above, region types may include text, photographs, equations, 15 drawings, tables, business graphics, etc. Furthermore, analysis code 17 in conjunction with uP 25 is the underlying processing engine that maintains the scanned image data. Analysis code 17 also includes scanned region type sensitivity logic 110 and scanned region clustering/declustering logic 120 of the present invention. Scanned region type sensitivity logic 110 resides within analysis code 17 , which communicates with data manager 21 over bus 24 and connection 28 . Data manager 21 communicates with bus 24 over connection 28 in order to access the data stored in RAM 16 in order to perform the preview scan operation or other post analysis tasks. Post analysis tasks may include, for example, printing, faxing, optical character recognition, etc. Region manager 22 communicates with bus 24 over connection 29 in order to access information pertaining to the region clustering maintained within analysis code 17 in order to draw the scanned image on display 19 during the preview scan operation.
Both scanned region type sensitivity logic 110 and scanned region clustering/declustering logic 120 are part of a probability based analysis engine, execute in uP 25 and will be discussed in detail below. User interface 13 illustratively includes preview scan block 18 , which allows a user of a scanner to view the document to be scanned prior to final scanning, or otherwise, prior to sending the appropriate scanned data regions to downstream destinations (applications, storage, etc.). Preview scan 18 outputs the scanned image on connection 32 for output to a user on display 19 .
FIG. 2 is a schematic view illustrating the user interface 13 and analysis code 17 of FIG. 1, in which the logic of the present invention resides. User interface 13 includes preview scan block 18 , which further includes user control 34 . User control 34 illustratively includes slide bar 36 and right click element 37 . Slide bar 36 may be a mode box (to be described in detail with reference to FIGS. 4 A- 4 N), or similar user interface that allows the adjustment of an attribute of a displayed element. Right click element 37 is typically the right mouse button available on a mouse user input device supplied with personal computers. Slide bar 36 and right click element 37 will be described in further detail with respect to FIGS. 4A-4N and 6 A- 6 E. Slide bar 36 communicates with application programming interface (API) 38 over connection 42 and right click element 37 communicates with API 38 over connection 44 . Scanned region type sensitivity logic 110 and scanned region clustering/declustering logic 120 reside within analysis code 17 and contain the logic necessary to allow a user to manipulate various scanned region information. API 38 communicates with analysis code 17 over connection 47 . Analysis code 17 also communicates with data manager 21 over connection 28 and with region manager 22 over connection 29 .
Scanned region type sensitivity logic 110 and scanned region clustering/declustering logic 120 are accessed by the API 38 calls through analysis code 17 over connection 47 . Analysis code 17 filters the correct API calls to send to either scanned region type sensitivity logic 110 or scanned region clustering/declustering logic 120 . Data manager 21 communicates with preview scan 18 over connection 26 and region manager 22 communicates with preview scan 18 over connection 31 in order to display preview scan information including regions and region data to a user over display 19 . Data manager 21 and region manager 22 receive information pertaining to manipulated regions from analysis code 17 over connections 28 and 29 , respectively.
In use, a user will view a scanned image on display 19 while user control 34 allows the user to manipulate the displayed image according to the user's preferences. For example, a user may adjust the sensitivity of a particular attribute of a region of a scanned image by using slide bar 36 to adjust the sensitivity of the attribute. This may be accomplished, for example, by adjusting the position of a pointer contained within slide bar 36 . By this adjustment slide bar 36 communicates a signal over connection 42 to API 38 . API 38 sends slide bar control information to analysis code 17 . This adjustment may indicate that a user wishes to change the sensitivity of a particular attribute of the displayed image and dictates the API call. API 38 communicates with analysis code 17 over connection 47 in order to update data manager 21 over connection 28 based upon the signal sent by API 38 . Data manager 21 stores the data that will be displayed to the user through user interface 13 on display 19 . Once a region attribute is adjusted, display 19 will display the adjusted regions to a user in real time. In this manner scanned region type sensitivity logic 110 , in cooperation with analysis code 17 , updates the set of regions generated by user interface 13 , while eliminating the requirement that the entire scanbed be recalculated.
In similar fashion, a user may adjust the grouping of regions by using right click element 37 to adjust the clustering/declustering of the scanned regions. This may be accomplished, for example, by right clicking the mouse while the mouse pointer is positioned over a particular region that the user might wish to manipulate. Right clicking the mouse button may expose a menu of region adjustment commands such as “delete”, “find”, “show background”, “hide background”, “show foreground regions”, “hide foreground regions”, “form composite”, “segment composite”, combine enclosed and containing regions”, and “separate enclosed and containing regions”.
A description of each region adjustment command follows. “Delete” changes a region from being “visible” to being “hidden”. “Find” brings a “hidden” region at the point clicked to being “visible”. “Show background” brings a background region that was “hidden” to being “visible”. “Hide background” is the opposite of “show background”. “Show foreground regions” makes “visible” all of the regions over the clicked background region, which had formerly been “hidden” (so that the background region had been represented as one clustered region rather than a background with foreground elements). “Hide foreground regions” is the opposite of “show foreground regions”. “Form composite” clusters together regions at the point clicked to form “composite” regions from the local “primitives”. “Segment composite” breaks up a “composite” region into its primitives. “Combine enclosed and containing regions” merges region primitives within a delimiting border with their border (clustering). “Separate enclosed and containing regions” divides a border region and its enclosed primitives into separate primitive regions.
Through the aforementioned adjustment right click element 37 communicates a signal over connection 44 to API 38 . This signal indicates that a user wishes to alter the grouping or clustering of regions in the displayed image and dictates the API call. API 38 communicates with analysis code 17 over connection 47 in order to update region manager 22 over connection 29 based upon the signal sent by API 38 . Region manager 22 stores the data that will be displayed to the user through user interface 13 on display 19 . Once the region grouping is adjusted in accordance with that described above, display 19 will display the revised region clustering to a user in real time. In this manner scanned region clustering/declustering logic 120 in cooperation with analysis code 17 updates the set of regions presented to a user, while eliminating the requirement that the entire scanbed be recalculated.
The scanned region type sensitivity logic 110 and the scanned region clustering/declustering logic 120 can be implemented using any reasonable set of algorithms for clustering and declustering segmented data and for ranking (by assigning probabilities) segmented regions for their region typedness.
For example, to illustrate a possible implementation of the scanned region type sensitivity logic 110 , a regular line of text may be assigned the following probabilities (called p-values in statistics, which must sum to 1.00 for 100% overall probability): text probability=0.99, drawing probability=0.01. A larger text line (such as a heading or title) may be assigned the following probabilities: text probability=0.45, drawing probability=0.55. Now, the default representation for the second text line will be drawing, since it may have a large enough size to warrant preservation of the exact “look and feel” of the large text (rather than matching it to the closest font available, as happens in optical character recognition (OCR) packages). However, if a slider (such as in FIG. 4B) were moved far enough to favor text (e.g. the slider adds successively more “p-value” to text), then the text representation will “outweigh” the drawing presentation. For example, if the slider is moved halfway over, its weight might be 0.20, and now text=0.45+0.2=0.65, which outweighs the 0.55 for drawing, and so the region shows up as text.
A similar statistical weighting can be used for making easy the clustering/declustering decisions. For example, to illustrate a possible implementation of the scanned region clustering/declustering logic 120 consider the case wherein the user right clicks on a region and selects “Form Composite” from a pop-up menu ( 175 of FIGS. 6 B- 6 D). Then, the scanned region clustering/declustering logic 120 selects the set of regions nearby the clicked point (using any reasonable clustering algorithm) to determine what type of cluster may be most appropriate to form. If a table is near the clicked point, for example, then there are likely to be predominantly text and rule primitives near the clicked point; in contrast, if a business graphic region is near the clicked point, then there is likely to be at least one large drawing region near the clicked point. As with all other regions using the underlying logic 110 and 120 , the clustered region will be assigned probabilities for all of the possible region types it may be.
For example, a table cluster may be assigned the following probabilities: table p=0.45, business graphic p=0.20, cartoon p=0.15, chart p=0.10, and equation p=0.10. Since the probability (p-value) is greatest for the table, the clustered region is designated a table. This demonstrates the value of the underlying probability scheme in the preferred embodiment of this invention; for, if the classification engine (any algorithm used to process the table region) decides that the clustered region is actually not a table, it can ask the scanned region clustering/declustering logic 120 to assign the cluster to the next most likely candidate (in this case, “business graphic”). In this manner, the underlying region statistics can be used to optimize the clustering/declustering accuracy.
FIG. 3 is a flow diagram illustrating the operation of the scanned region type sensitivity logic 110 of FIGS. 1 and 2. In block 111 the scanned regions are displayed to a user on display 19 . The regions are displayed in accordance with the default settings applied by analysis code 17 . Although analysis code 17 contains all the data pertaining to each region, only the regions generated by the default settings are displayed initially.
In block 112 it is determined whether the user is satisfied with the regions as displayed in block 111 . If the user is satisfied with the display, then in block 117 post analysis tasks such as faxing, printing, optical character recognition, etc., are performed as those skilled in the art will appreciate. If, however, in decision block 112 it is determined that the regions as displayed are not to the users liking, then through the use of the scanned region type sensitivity logic 110 and slide bar 36 , the user may adjust the sensitivity of any displayed region so that the desired attributes for the user's particular application are displayed.
In block 114 the user updates the desired regions by actuating slide bar 36 in accordance with that described with reference to FIG. 2 . Illustratively, the user is presented with a mode box containing a slide bar 36 adjustment. The user may adjust the sensitivity of the particular attribute assigned to the particular region of interest.
Next, in block 118 , analysis code 17 is accessed in order to obtain the desired region characteristics, and in block 116 , the region is retyped and once again displayed to a user on display 19 with the regions updated in real time. The user may accept the revised regions and proceed or may adjust the region sensitivity again.
FIGS. 4A-4N collectively illustrate the results obtained through the operation of the scanned region type sensitivity logic 110 of FIGS. 1, 2 and 3 . FIG. 4A is a view illustrating a representative scanned page 150 . Page 150 illustratively includes text over white background 151 , photograph 152 , drawing 154 , text over shaded background 156 , larger font size text 157 , special text 158 , and inverted text 159 . Page 150 can be, for example, a typical page in a magazine, book, or document in which multiple types of information are contained on a page.
FIG. 4B illustrates slide bar 36 having a setting illustrated by pointer 51 in which the text sensitivity is minimized. In this setting, slide bar 36 instructs scanned region type sensitivity logic 110 to display no text at all and page 150 would appear as blank.
FIGS. 4C and 4D illustrate scanned page 150 in which a minimal amount of text over white background 151 is displayed, corresponding to a minimal setting of pointer 51 of slide bar 36 (FIG. 4 D). Notice that pointer 51 is adjusted slightly away from the setting illustrated in FIG. 4B, in which no text was displayed. Essentially, by increasing the sensitivity of an attribute (in this example, text) via slide bar 36 , the scanned region type sensitivity logic 110 makes more regions appear as text. This corresponds to the description of the probability algorithm described with respect to FIG. 2 . For example, text probability is assigned as 0 . 45 . By moving pointer 51 of slide bar 36 to the right (thus increasing text sensitivity) additional “pvalue” is added to the text probability. In this manner more of the image will appear as text.
FIGS. 4E and 4F illustrate scanned page 150 in which the pointer 51 of slide bar 36 (FIG. 4F) is adjusted to increase further the text sensitivity. As can be seen both text over white background 151 and text over shaded background 156 is now displayed. By increasing the sensitivity using slide bar 36 , additional text is displayed. This illustrates that even if analysis code 17 initially classified text as for example a drawing, by increasing the sensitivity 36 of the scanned region type sensitivity logic 110 , a user may revise the attributes of regions that were not initially classified as text so as to be displayed as text. Essentially, movement of slide bar 36 tips the p-value “balance” in favor of regions being classified as text even if they originally had a higher probability of being classified as another type of region. This feature gives the user of a scanner product heretofore unavailable ability to manipulate the region sensitivity and allows a user to efficiently tailor the appearance of a scanned image for any particular application.
FIGS. 4G and 4H illustrate scanned page 150 in which pointer 51 of slide bar 36 (FIG. 4H) is adjusted to increase further the sensitivity of scanned text. As can be seen, in addition to text over white background 151 and text over shaded background 156 , included at this higher sensitivity adjustment is larger font size text 157 . As can be seen, by increasing the sensitivity of the scanned region type sensitivity logic 110 using slide bar 36 , more and more regions that were initially classified as something other than text are caused to appear as text.
FIGS. 41 and 4J illustrate scanned page 150 in which pointer 51 of slide bar 36 (FIG. 4J) is adjusted yet higher in sensitivity. As can be seen special text 158 now appears in the scanned image. Special text 158 may be, for example, a larger font size first letter of a paragraph that may have initially been classified by analysis code 17 as a drawing due to its larger size, but, due to the increase in text sensitivity as requested by a user through input from slide bar 36 , is now shown as text. Special text 158 may also be, for example, part of a logo at the bottom of page 150 .
FIGS. 4K and 4L illustrate scanned page 150 in which pointer 51 of slide bar 36 (FIG. 4L) is adjusted even higher in sensitivity. This adjustment now causes scanned region type sensitivity logic 110 to display inverted text 159 as text. Inverted text 159 can be text in which the foreground and background colors have been reversed, for example, from black text with white background to white text with black background. Inverted text 159 may have initially been classified by analysis code 17 as drawing information, but is now displayed as text.
FIGS. 4M and 4N illustrate scanned page 150 in which pointer 51 of slide bar 36 (FIG. 4N) is adjusted to a maximum sensitivity causing extraneous writing 161 (which is illustratively stray handwriting on the page) to be displayed to a user as text. As can be seen, as the text sensitivity is adjusted higher, more regions are displayed as text While illustrated herein using text, the adjustment of region attributes may include all available region types including, but not limited to, drawings, photographs, equations, tables, etc.
FIG. 5 is a flow diagram illustrating the operation of the scanned region clustering/declustering logic 120 of FIGS. 1 and 2. In block 121 the scanned regions are displayed to a user on display 19 . The regions are displayed in accordance with the default settings applied by analysis code 17 . Although analysis code 17 contains all the data pertaining to each region, only the region clustering generated by the default settings are displayed initially.
In block 122 it is determined whether the user is satisfied with the regions as displayed in block 121 . If the user is satisfied with the displayed regions, then in block 127 post analysis tasks such as faxing, printing, optical character recognition, etc., are performed as those skilled in the art will appreciate. If, however, in decision block 122 it is determined that the regions as displayed are not as desired by a user, then through the use of the scanned region clustering/declustering logic 120 and right click element 37 , a user may adjust the clustering of any displayed region so that the desired attributes for the user's particular application are displayed.
In block 124 the user updates the desired regions by actuating, for example, right click element 37 in accordance with that described with reference to FIG. 2 . Illustratively, a user may right click on a particular region and be presented with a list of menu choices corresponding to available region grouping adjustment options The user may adjust the clustering, or grouping, of the regions in order to obtain the desired region clustering.
Next, in block 128 , analysis code 17 is accessed in order to obtain the desired region characteristics, and in block 126 , the regions are recomputed and once again displayed to a user on display 19 with the region clustering updated in real time. The user may accept the revised region clustering or may adjust the region clustering again.
FIGS. 6A-6E collectively illustrate the results obtained by the operation of the scanned region clustering/declustering logic 120 of FIGS. 1, 2 and 5 . FIG. 6A is a view illustrating a scanned image 170 . Scanned image 170 illustratively includes text 171 , photographs 172 , large text 174 , business graphic 177 in the form of a pie chart, and text 178 surrounding business graphic 177 .
FIG. 6B is a view illustrating pie chart 177 selected by a user of a scanner by right clicking 37 (FIG. 2) through user interface 13 (FIG. 2 ). By right clicking, a menu 175 may be presented to a user on display 19 giving the user a selection of commands with which to manipulate the selected region or regions.
FIG. 6C is a view illustrating pie chart 177 clustered with text 178 surrounding pie chart 177 . This is accomplished by a user of a scanner product right clicking 37 (FIG. 2) a mouse while the cursor is positioned over the pie chart 177 . Illustratively, a user right clicks over pie chart 177 , and selects menu option “form composite”. By selecting “form composite” the result is as shown in FIG. 6C wherein pie chart 177 and text 178 surrounding pie chart 177 are clustered together forming region 179 .
Essentially, the scanned region clustering/declustering logic 120 uses input from a user interface ( 37 of FIG. 2) to access analysis code 17 to group the selected regions (i.e., pie chart region 177 and text 178 surrounding pie chart 177 ) into a particular region that the user selects. For example, pie chart region 177 and text 178 surrounding pie chart region 177 may by regrouped into region 179 as a “business graphic”, or as a new region type.
Conversely, if a user right clicks over region 179 and selects “segment composite” from the displayed menu 175 , region 179 will be segmented, or declustered, resulting in separate regions 177 and 178 , as previously illustrated in FIG. 6 B.
FIG. 6D is a view illustrating large text character 176 as selected by a user right clicking over the character. By enabling the “form composite” command from menu 175 , exposed by right clicking over large text character 176 , a user can cluster the large text into region 181 as shown in FIG. 6 E. Conversely, by right clicking over region 181 and selecting “segment composite”, region 181 can be declustered into regions 174 and 176 .
It will be obvious to those skilled in the art that many modifications and variations may be made to the preferred embodiments of the present invention, as set forth above, without departing substantially from the principles of the present invention. For example, the system and method for manipulating regions in a scanned image can be implemented using various scanning and computing products. Furthermore, the system and method for manipulating regions in a scanned image is useful for manipulating documents from a digital database/file system or from other digital capture devices, such as video capture systems and digital cameras. All such modifications and variations are intended to be included herein within the scope of the present invention, as defined in the claims that follow. | Scanned region type sensitivity logic and scanned region clustering/declustering logic allow the manipulation of regions within a scanned image. A scanned region type sensitivity logic allows the manipulation of region type attributes by allowing a user of a scanner product, through the use of a user interface, to adjust the sensitivity of a particular region type in real time, with the results of the adjustment displayed back to the user through the user interface. A scanned region clustering/declustering logic allows a user of a scanner product, through the use of a user interface, to manipulate the grouping of regions displayed to the user in real time. Both of these forms of scanning logic are predicated on the underlying use of a document analysis technology that stores probabilities (“p-values”) or other relative statistics on all plausible region types as part of the definition of the regions. | 6 |
RELATED APPLICATIONS
The present application claims priority from U.S. Provisional application No. 61/344,731 filed on Sep. 23, 2010, the disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
The present disclosure relates generally to imaging the insides of a patient's colon using an intra-lumen imaging capsule and more specifically to estimating the distance from the capsule to the internal walls of the colon and estimating the size of lesions thereof.
BACKGROUND
One method of examining the gastrointestinal tract for the existence of polyps and other clinically relevant features that may provide an indication regarding the potential of cancer is performed by swallowing an imaging capsule that will travel through the entire gastrointestinal (GI) tract and view the patient's situation from the inside. In a typical case the trip can take between 24-48 hours, after which the imaging capsule exits in the patient's feces. Typically the patient swallows a contrast agent to enhance the imaging ability of the imaging capsule. Then the patient swallows the imaging capsule to examine the gastrointestinal tract while flowing through the contrast agent. The imaging capsule typically includes a radiation source, for example including a radioisotope that emits X-rays or Gamma rays. The radiation is typically collimated to allow it to be controllably directed in a specific direction during the imaging process. In an exemplary case the imaging capsule is designed to measure Compton backscattering and transmits the measurements (e.g. count rate) to an external analysis device, for example a computer or other dedicated instruments.
In a typical implementation a radio-opaque contrast agent is used so that a position with a polyp will have less contrast agent and will measure a larger back-scattering count to enhance accuracy of the measurements. Alternatively, other methods may be used to image the gastrointestinal tract.
U.S. Pat. No. 7,787,926 to Kimchy, the disclosure of which is incorporated herein by reference, describes details related to the manufacture and use of such an imaging capsule.
One challenge in estimating the distance from the imaging capsule to the inner walls of the colon is that the measurements are affected by the radiation blocking ability of the contents surrounding the imaging capsule: generally the contrast agent. The blocking ability of the contrast agent is dependent on the concentration of the contrast agent. Generally the patient can swallow a contrast agent of a specific concentration, however while advancing through the GI tract the water contained in the colon contents is absorbed by the colon leaving a less diluted solution have a higher concentration of contrast agent surrounding the imaging capsule. Additionally in some cases the patient is required to drink more contrast agent at specific times to assure proper functionality of the imaging capsule. Therefore at any specific position the concentration is not known. As a result the distance measurements may not be accurate as desired.
There is thus a need for improved methods of measuring the distance from the imaging capsule to the walls of the colon.
SUMMARY
An aspect of an embodiment of the disclosure relates to a system and method for measuring distances inside a patient's colon and optionally using the measurements to construct an image of the inside of the colon. The patient swallows a radio opaque contrast agent and then swallows an imaging capsule. The imaging capsule emits radiation at its current location in the colon and then detects photons that are returned from interactions of the radiation with an inner will of the colon and the contents of the colon, for example the contrast agent.
Two types of interactions with the radiation produce most of the returned photons:
1. X-ray fluorescence;
2. Compton back-scattering.
The photons of each type of interaction have specific ranges of energy and can be identified by the energy level of the detected photons. The system counts the photons for each energy level and then summates the photons with energy levels corresponding to X-ray fluorescence interactions to form a first count and the photons with energy levels corresponding to Compton back-scattering to form a second count. The first count and second count are then used to determine the distance from the imaging capsule to the inner wall of the colon and to determine the concentration of the contrast agent at the location of the imaging capsule.
In an exemplary embodiment of the disclosure, the emitting and detecting are performed on the entire circumference of the inner wall of the colon at the location of the imaging capsule. Optionally, the emitting and detecting are performed repeatedly along the length of the colon as the imaging capsule progresses.
in an exemplary embodiment of the disclosure, the information from the detecting is transmitted wirelessly to an external processing device (e.g. a computer) having a program that handles the information. Optionally, the external computer counts the photons according to their energy level and summates them according to the type of interaction that they initiated from. Alternatively, the imaging capsule may summate the photons according to the type of interaction and transmit the results to the computer.
In an exemplary embodiment of the disclosure, the determined distances are used to determine the size and location of polyps inside the colon and to construct images of the inside of the colon.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure will be understood and better appreciated from the following detailed description taken in conjunction with the drawings. Identical structures, elements or parts, which appear in more than one figure, are generally labeled with the same or similar number in all the figures in which they appear, wherein:
FIG. 1A is a schematic cross sectional side view of an imaging capsule deployed in a patient's colon, according to an exemplary embodiment of the disclosure;
FIG. 1B is a schematic cross sectional view of an imaging capsule deployed in a patient's colon, according to an exemplary embodiment of the disclosure;
FIG. 2 is a schematic illustration of a graph of a count of detected photons, according to an exemplary embodiment of the disclosure;
FIG. 3 is a schematic illustration of images of the inside of a colon, according to an exemplary embodiment of the disclosure;
FIG. 4 is a schematic illustration of an experiment demonstrating the calculation of distances in the colon, according to an exemplary embodiment of the disclosure;
FIG. 5 is a schematic illustration of a graph depicting the experimental results showing the relationship of the photon count, distance from the radiation source and concentration of the contrast agent, according to an exemplary embodiment of the disclosure;
FIG. 6A is a schematic illustration of a graph depicting a surface representing the distance as a function of the count and contrast agent concentration for X-Ray fluorescence, according to an exemplary embodiment of the disclosure;
FIG. 6B is a schematic illustration of a graph depicting a surface representing the distance as a function of the count and contrast agent concentration for Compton back-scattering, according to an exemplary embodiment of the disclosure;
FIG. 7 is a schematic illustration of a graph depicting an estimation of distance and concentration for a specific photon count, according to an exemplary embodiment of the disclosure; and
FIGS. 8A , 8 B and 8 C are schematic graphs that demonstrate the relationship between an estimated distance and a real distance as a function of concentration, according to an exemplary embodiment of the disclosure.
DETAILED DESCRIPTION
FIG. 1A is a schematic cross sectional side view of an imaging capsule 100 deployed in a patient's colon 105 , and FIG. 1B is a schematic cross sectional view of an imaging capsule 100 deployed in a patient's colon 105 , according to an exemplary embodiment of the disclosure. In an exemplary embodiment of the disclosure, the patient first drinks a contrast agent 140 that mixes with the colon contents. The contrast agent 140 assists in enabling the imaging capsule 100 to perform measurements and form a 3-dimensional image of colon 105 from the inside. Optionally, the contrast agent 140 includes water mixed with a radio opaque material with a relatively high atomic number such as, for example, Barium (atomic number 56) or Iodine (atomic number 53). After drinking the contrast agent 140 the patient swallows imaging capsule 100 . Imaging capsule 100 travels through the patient's GI tract and through the colon until it exits in the patient's feces.
In an exemplary embodiment of the disclosure, imaging capsule 100 includes a radiation emitter 120 and a radiation detector 130 . In some aspects, the radiation emitter 120 provides a collimated radiation beam that emits radiation while rotating 360 degrees inside imaging capsule 100 to scan the entire inner circumference of the colon walls 110 as the imaging capsule progresses through the colon. In an exemplary embodiment of the disclosure, radiation detector 130 rotates with radiation emitter 120 to detect the photons that are returned from interactions with the emitted radiation. In some aspects, radiation detector 130 may include detectors surrounding the outer circumference of imaging capsule 100 to detect radiation from all sides of imaging capsule 100 . in some aspects, radiation detector 130 may he a solid state detector, for example a Cadmium Telluride (CdT 1 ) compound serving as a detector. In an exemplary embodiment of the disclosure, imaging capsule 100 emits X-ray radiation and measures photons returned by two physical phenomenon causing interactions with the radiation. In an exemplary embodiment of the disclosure, the two physical phenomenons are Compton back-scattering and X-ray fluorescence. The measured photons related to these phenomenon are used to determine the distance 160 from imaging, capsule 100 to the surrounding walls 110 of the colon or the distance 150 to polyps 115 extending from the inner walls 110 of the colon 105 .
In an exemplary embodiment of the disclosure, imaging capsule 100 includes a transmitter 135 (e.g. an RF transmitter) to transmit the measurements to an external processing device 190 for processing. In an exemplary embodiment of the disclosure, processing device 190 is a general purpose computer with an executable program 195 that accepts the measurements from the imaging capsule 100 . Optionally, program 195 determines the distances (e.g. 150 and 160 ) inside colon 105 and constructs a 3 dimensional image of the colon for a medical practitioner to view. Optionally, the processing device 190 also determines the width 170 and height ( 160 - 150 ) of polyps extending from the colon walls 110 . In an exemplary embodiment of the disclosure, imaging capsule 100 travels in the longitudinal direction through the colon. The imaging capsule 100 may be off center sometimes during the journey. In an exemplary embodiment of the disclosure, program 195 compensates for deviations from the center by using the measurements that are performed on the entire circumference inside the colon and adjusting the results if necessary.
In some embodiments of the disclosure, imaging capsule 100 may include an internal processing device and transmit 3-dimensional images directly to an external viewing device for the medical practitioner to view.
In an exemplary embodiment of the disclosure, the radiation emitter emits X-ray radiation, for example between 10 to 100 KeV (e.g. 59.4 KeV). Optionally, the X-ray photons interact with the contrast agent, the contents of the colon and the tissue of the colon walls 110 . The interactions cause the return of photons to detector 130 based on two physical phenomenons:
1. Compton back-scattering (CMT)—The X-ray photons emitted from imaging capsule 100 collide with the electrons of the colon content and the tissue of the colon walls 110 and provide back-scattered photons of specific energies, which are detected by detector 130 . Additionally, the backscattered photons are attenuated by the distance traveled. The larger the distance that the back-scattered photons travel through the contrast agent 140 the less the number of back-scattered photons that will be detected since the contrast agent enhances absorption of the photons. When a polyp 115 exists on the colon wall 110 the distance is shorter, less contrast agent absorbs the photons and more will he detected by detector 130 .
2. X-ray Fluorescence (XRF)—The X-ray photons emitted from the imaging capsule interact with the atoms of the contrast agent and the rest of the contents of the colon 105 , The interactions cause ionization, which yields a fluorescent photon flux with specific energy levels from the heavy atoms in the contrast agent such as Iodine or Barium. Additionally, the larger the distance from imaging capsule 100 the more X-ray fluorescence will be detected and the shorter the distance the less X-ray florescence will be detected.
The photon energy (KeV) far the photons released by each of the two physical phenomenon is different so the results from each phenomenon can be analyzed independently. FIG, 2 is a schematic illustration of a graph 200 of a count of detected photons, according to an exemplary embodiment of the disclosure. In a. typical case the X-ray fluorescence forms the two highest peaks on the of left side of the graph (lower energies) and the Compton back-scattering forms the highest peak on the right side of the graph (higher energies). The energies of the peaks are generally known since they depend mainly on the energy of the emitted radiation, the compounds in the contrast agent and the geometry between the radiation emitted and the detector's position relative to the emitter.
FIG. 3 is a schematic illustration of images 300 of a colon, according to an exemplary embodiment of the disclosure. Image 310 shows a computer reconstructed cross sectional perspective. view of the inside of colon 105 with a polyp 115 on the bottom surface. Image 310 is reconstructed based on the measurements of imaging capsule 100 . Image 320 shows a longitudinal side view of the inside of the colon 105 with polyp 115 and image 330 shows a cross sectional view of the colon at the position of the polyp 115 .
Following are details of an experiment 400 conducted to demonstrate the connection between the distances ( 150 , 160 and 170 ) and the results measured. from Compton back-scattering and X-ray fluorescence as described above. FIG. 4 is a schematic illustration of the setup of experiment 400 to demonstrate the calculation of distances in the colon 105 , according to an exemplary embodiment of the disclosure. In an exemplary embodiment of the disclosure, a tank 410 of water mixed with a contrast agent 430 is used to demonstrate colon 105 . A slab 420 of plastic with the same density as water is used to demonstrate the colon tissue and the tissues beyond. A collimated radiation source 440 emitting X-ray radiation at 59.4 Key (e.g. using an Am 241 radiation source) is used to provide X-ray radiation. A solid state (CdT 1 ) radiation detector 450 counts photons that are released responsive to the X-ray radiation. The measurements are provided to a transmitter 460 that transmits the measurements wirelessly to processing device 190 , such as, for example, a computer that executes program 195 .
In an exemplary embodiment of the disclosure, slab 420 was positioned at various distances (e.g. 0-30 mm) relative to the radiation source 440 to see the effect on the measurements. Additionally, the measurements were repeated for various concentrations of contrast agent 430 , for example 1% -8%. The graph in FIG. 2 shows a typical spectrum with two areas:
1. Area 210 representing the results from X-ray florescence with 2 peaks, for example one large and one smaller between 30 KeV and 35 KeV, and
2. Area 220 representing the results from Compton back-scattering with a peak, for example between 40-45 KeV.
The results of area 210 and area 220 for various distances and contrast agent concentrations were integrated and provided in graphical form. FIG. 5 is a schematic illustration of a graph 500 depicting the experimental results showing the relationship of the photon count, distance from the radiation source and concentration of the contrast agent, according to an exemplary embodiment of the disclosure. The lower lines correspond to X-ray fluorescence and the upper lines correspond to Compton back-scattering. Each line represents a different concentration percentage for various distances. As shown in graph 500 the more concentrated the contrast agent the greater the count the for X-ray fluorescence and the lower the count for Compton back-scattering. Likewise the greater the distance from the radiation source the greater the count for X-ray fluorescence. and the lower the count for Compton back-scattering.
In an exemplary embodiment of the disclosure, program 195 is required m determine the distance L as a function of the counts (I) of the X-ray florescence and Compton back-scattering (i.e. L=L(I CMT , I XRF )).
FIG. 6A is a schematic. illustration of a graph 600 depicting a surface representing the distance (L) as a function of the count (I) and contrast agent concentration (Ro) for X-Ray fluorescence, and FIG. 6B is a schematic illustration of a graph 650 depicting a surface representing the distance (L) as a function of the count (I) and contrast agent concentration Ro) for Compton back-scattering, according to an exemplary embodiment of the disclosure.
In an exemplary embodiment of the disclosure, for specific count values (I CMT , I XRF ) at a specific moment (when the imaging capsule is at a specific position) a set of 2 functions can be obtained from the surfaces in graphs 600 and 650 providing an estimated distance (L EST ) as a function o the concentration of contrast agent 430 (a line on the surface representing a specific concentration):
L EST =L CMT (Ro, I CMT =constant); and
L EST =L XRF (Ro, I XRF =constant).
Optionally, program 195 finds the intersection point of the 2 curves yielding the estimated distance L EST and the concentration (Ro). FIG. 7 is a schematic illustration of a graph 700 depicting an estimation of the distance L EST and concentration (Ro) for a specific photon count, according to an exemplary embodiment of the disclosure.
In an exemplary embodiment of the disclosure, during live application of imaging capsule 100 through a patient's colon 105 , various disturbances may hinder the calculations described above and disturb the smoothness of the results, for example the concentration of the contrast agent varies throughout the colon 105 . Additionally, the concentration is lower at the beginning and increases toward the exit from the colon due to absorption of water from the colon leaving the molecules of the contrast agent at a higher concentration. In order to overcome disturbances the following method and assumptions are used:
1. The contrast agent concentration (Ro) is assumed to change gently along the colon tract.
2. The results of the concentration will be calculated based on the estimation calculations used above.
3. The concentration for a sequence of positions will be filtered by regression to provide a smooth function.
4. The smoothed concentration function will be used to estimate the distance 160 either using the Compton back-scattering curve or the X-ray fluorescence curve (as shown in FIG.7 ):
L EST =L CMT ( Ro smooth , I CMT =constant) or L EST =L XRF ( Ro smooth , I XRF =constant).
In an exemplary embodiment of the disclosure, the performance of the estimation calculation is evaluated by comparing the estimated distance (L EST ) to the real (L REAL ) distance in the experiment described above. FIGS. 8A , 8 B and 8 C are schematic graphs that demonstrate the relationship between the estimated distance and the real distance as a function of the concentration (Ro). The figures show two dotted outer lines showing the boundaries of the results based on the measurements and two inner lines one showing the standard deviation of the measured results and one showing the mean of the measured results. FIG. 8A shows the relationship for Ro=8%, FIG. 8B shows the relationship for Ro=6% and FIG. 8C shows the relationship for Ro=4%. The results of the graph show that good results can be obtained for distances up to 20 mm with a concentration of 8% and larger distances for lower concentration. Typically imaging capsule 100 will travel along the longitudinal direction, which has a typical diameter of 30-40 mm and a maximum of up to about 50 mm. However it should be noted that during movement, the colon typically contracts to less than 50% of its normal diameter leaving a short distance between the colon wall 110 and imaging capsule 100 in the order of 5-15 mm at the most.
In an exemplary embodiment of the disclosure, after calculating the distance from imaging capsule 100 to the colon walls 110 other measurements may be calculated based on the results. In an exemplary embodiment of the disclosure, the width (D) 170 ( FIG. 1B ) of a polyp 115 can be estimated by calculating an angle (A) 180 enclosing the polyp 115 , for example the angle between two scanning positions during rotation of the radiation source where the length is larger than the length over width D because of the polyp 115 or that the length is substantially the same as the rest of the circumference except over width D. Additionally, geometric calculations can be used to determine the width of polyp 115 , for example by calculating D=2*L*Tan(A/ 2 ).
It should be appreciated that the above described methods and apparatus may be varied in many ways, including omitting or adding steps, changing the order of steps and the type of devices used. It should be appreciated that different features may be combined in different ways. In particular, not all the features shown above in a particular embodiment are necessary in every embodiment of the disclosure. Further combinations of the above features are also considered to be within the scope of some embodiments of the disclosure.
It will be appreciated by persons skilled in the art that the present disclosure is not limited to what has been particularly shown and described hereinabove. | A method of estimating distances in a colon of a subject, including: orally administering to a subject a contrast agent, orally administering an imaging capsule to the subject, emitting radiation from the imaging capsule at a location in the colon, detecting photons that are returned from an interaction of the radiation with an inner wall of the colon and contents of the colon, summating the detected photons with energies corresponding to X-ray fluorescence interactions to form a first count, summating the detected photons with energies corresponding to Compton back-scattering interactions to form a second count, determining the distance from the imaging capsule to the inner wall of the colon and a concentration of the contrast agent at the location of the imaging capsule in the colon using the values of the first count and the second count. | 0 |
[0001] This application is a continuation of U.S. patent application Ser. No. 13/644,114 filed on Oct. 3, 2012, which claims the benefit of commonly-owned U.S. provisional application No. 61/544,347 filed on Oct. 7, 2011, each of which is incorporated herein and made a part hereof by reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates generally to the field of label printers, such as those used for food preparation and inventory freshness. More particularly, the present invention relates to a tilting touch screen for a label printer and an improved label printer with such a tilting touch screen.
[0003] Restaurants are required to keep track of stored and/or refrigerated food products and ingredients. Label printers are provided in the food preparation/storage area of a restaurant and are used to create “freshness labels” for each package of food or ingredients which specify, among other things, the product/ingredient name, the arrival date and expiration date (and optionally time) for each package. A menu database is created for each class of food items used by a restaurant (sandwiches, salads, drinks, etc.), and the ingredients for each item are provided in the database. The menu database is downloaded to the printer terminal along with parameters for label size, format, expiration dates (or freshness periods), and the like. The label printer may include two print mechanisms, one for printing freshness labels and the other for printing nutritional information, ingredient labels, coupons, receipts, or the like.
[0004] Typical prior art label printers used to print freshness labels such as the Avery Dennison Monarch 9415 are expensive, have a large footprint, and provide unfavorable screen angles and features.
[0005] It would be advantageous to provide an improved label printer that is cheaper, smaller, easier to use, and easier to maintain than prior art label printers.
[0006] The methods and apparatus of the present invention provide the foregoing and other advantages.
SUMMARY OF THE INVENTION
[0007] The present invention relates to a tilting touch screen for a printer and a printer having such a tilting touch screen.
[0008] In one example embodiment of a tilting touch screen for a printer in accordance with the present invention, the tilting touch screen comprises a touch screen housing, a touch screen located in the touch screen housing, means for pivotally connecting the touch screen housing to a printer housing, the printer housing defining an opening closable by the tilting touch screen, and a controller for controlling the printer in communication with the touch screen.
[0009] The means for pivotally connecting the touch screen housing to the printer housing may comprise pivot arms pivotally coupling the touch screen housing to oppositely disposed inside surfaces of the printer housing at a corresponding pivot points. The pivot arms may each have a free end which extends beyond the corresponding pivot point. The free ends of the pivot arms may be resilient. Each of the free ends of the pivot arms may bear a corresponding protrusion. Each of the free ends of the pivot arms with the corresponding protrusion may be adapted to springingly engage into corresponding recesses in the oppositely disposed inside surfaces of the printer housing upon tilting of the touch screen into at least one of a fully open and a fully closed position. The protrusion may be adapted to be released from engagement with the corresponding recess upon tilting of the touch screen from the at least one of the fully open and the fully closed position.
[0010] Upper and lower recesses may be provided on the oppositely disposed inside surfaces of the printer housing. The free ends of the arms with the corresponding protrusions may spring into the lower recesses when the touch screen is tilted into the fully open position. The free ends of the arms with the corresponding protrusions may spring into the upper recesses when the touch screen is tilted into the fully closed position. In addition, one or more intermediate recesses may be provided for positioning the tilting touch screen in one or more corresponding positions between the fully open and the fully closed position.
[0011] In an alternate example embodiment, the means for pivotally connecting the touch screen housing to the printer housing may comprise counterbalanced friction hinges coupling the touch screen housing to oppositely disposed inside surfaces of the printer housing. The counterbalanced friction hinges may comprise a torsion spring and/or a friction clutch assembly.
[0012] In one example embodiment, the tilting touch screen may further comprise at least one print mechanism located in the tilting screen housing and in communication with the controller. Each of the at least one print mechanisms may comprise a print head, a stepper motor, and a top-of-form sensor. A platen associated with each of the at least one print mechanisms may be located in the printer housing. The tilting touch screen may further comprise a mechanical interface between the at least one print mechanism and the platen. The mechanical interface may further comprise at least one guiding surface for orienting the at least one print head with the platen.
[0013] A paper bucket associated with each of said at least one print mechanisms may be located in the printer housing and accessible upon tilting the touch screen into an open position. The paper bucket may be configured to receive one of a roll of paper or a fan-folded length of paper feedable to the at least one print mechanism.
[0014] In an alternate example embodiment, at least one print mechanism and at least one associated platen may be located in the printer housing. In such an example embodiment, the at least one print mechanism may be adapted to be connected to the tilting touch screen via detachable flexible flat cables. A driver card associated with the at least one print mechanism may be in communication with the controller via the detachable flexible flat cable. The controller may comprise a logic output adapted to be directed through the detachable flexible flat cable to the driver card to drive the printer. The at least one print mechanism may comprise a removable clamshell-type mechanism.
[0015] The touch screen may comprise at least a touch screen overlay and an LCD. The controller may be in communication with the touch screen, the LCD, and print mechanisms of the printer.
[0016] A layout of the touch screen overlay may be configurable. A partially translucent overlay may be provided between the touch screen overlay and the LCD, with permanent buttons being provided for controlling main printer functions on the partially translucent overlay outside of an area of the LCD.
[0017] The controller may comprise a printed circuit board mounted directly to a rear surface of the LCD. The touch screen may also comprise an SD micro card reader in communication with the controller.
[0018] A latching mechanism may be provided for securing the touch screen housing to the printer housing in a closed position. For example, the latching mechanism may comprise at least one magnet fixed to one of the touch screen housing or the printer housing and at least one corresponding metal striker plate fixed to the other of the touch screen housing or the printer housing.
[0019] A bracket may be provided which is adapted to be coupled to the printer housing for mounting the printer to a wall surface. The touch screen housing may be adapted to be pivoted open without extending beyond a back wall of the printer housing, to avoid interference issues when the printer housing is wall mounted.
[0020] The present invention also encompasses a printer having a tilting touch screen. In one example embodiment, such a printer having a tilting touch screen may comprise a printer housing, a touch screen housing, a touch screen located in the touch screen housing, means for pivotally connecting the touch screen housing to the printer housing, the printer housing defining an opening closable by the tilting touch screen, and a controller for controlling the printer in communication with the touch screen. The printer may also include additional features discussed above in connection with the various embodiments of the tilting touch screen.
[0021] The present invention also encompasses a method of providing a tilting touch screen for a printer. One example embodiment of the method may comprise the steps of providing a touch screen housing, providing a touch screen located in the touch screen housing, providing means for pivotally connecting the touch screen housing to a printer housing, the printer housing defining an opening closable by the tilting touch screen, and providing a controller for controlling the printer in communication with the touch screen.
[0022] The method may also include additional features discussed above in connection with the various embodiments of the tilting touch screen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention will hereinafter be described in conjunction with the appended drawing figures, wherein like reference numerals denote like elements, and:
[0024] FIG. 1 shows an example embodiment of a printer in accordance with the present invention;
[0025] FIG. 2 shows a representation of a front view of an example embodiment of a touch screen in accordance with the present invention;
[0026] FIG. 3 shows a representation of a side view of an example embodiment of a touch screen in accordance with the present invention;
[0027] FIG. 4 shows an example embodiment of a screen layout of a touch screen in accordance with the present invention;
[0028] FIG. 5 shows a first example embodiment of a tilting touch screen in accordance with the present invention;
[0029] FIG. 6 shows a block diagram of the electronic architecture of the example embodiment of the touch screen of FIG. 5 ;
[0030] FIG. 7 shows a second example embodiment of a tilting touch screen in accordance with the present invention;
[0031] FIG. 8 shows a block diagram of the electronic architecture of the example embodiment of the touch screen of FIG. 7 ;
[0032] FIG. 9 shows a side view of an example embodiment of a printer with the touch screen tilted open in accordance with the present invention;
[0033] FIG. 10A shows a perspective view of an example embodiment of the printer with the touch screen tilted open, illustrating an example embodiment of a mechanism for tilting the touch screen;
[0034] FIG. 10B shows a partial perspective view of a example embodiment of the printer with the touch screen tilted open, illustrating a further example embodiment of a mechanism for tilting the touch screen;
[0035] FIG. 10C shows a further example embodiment of a mechanism for tilting the touch screen;
[0036] FIG. 10D shows an exploded view of the mechanism of FIG. 10C
[0037] FIG. 11 shows an example embodiment of a latching mechanism for the touch screen housing;
[0038] FIG. 12 shows an example embodiment of a wall bracket for a printer in accordance with the present invention;
[0039] FIG. 13 shows a rear perspective view of the wall bracket of FIG. 12 connected to the printer in a first position in accordance with the present invention;
[0040] FIG. 14 shows a rear perspective view of the wall bracket of FIG. 12 connected to printer in a second position;
[0041] FIG. 15 shows a close-up view of the interior connections between the bracket and the printer in the first position shown in FIG. 13 ; and
[0042] FIG. 16 shows a close-up view of the interior connections between the bracket and the printer in the second position shown in FIG. 14 .
DETAILED DESCRIPTION
[0043] The ensuing detailed description provides exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the exemplary embodiments will provide those skilled in the art with an enabling description for implementing an embodiment of the invention. It should be understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention as set forth in the appended claims.
[0044] The present invention relates to a tilting touch screen for a printer and a printer having such a tilting touch screen. The present invention is applicable for use as a label printer for printing “freshness labels” for food product preparation and inventory storage.
[0045] As shown generally in FIG. 1 , the printer 10 may be provided with a touch screen 12 . The touch screen 12 may be angled at an advantageous viewing angle for a typical table or wall mount installation. The printer may also be provided with adjustable feet or legs for adjusting the viewing angle when installed on a shelf or desk (e.g., screw type feet, fold out legs, or the like).
[0046] As shown in FIGS. 2 and 3 , the touch screen 12 may comprise an LCD area 16 with a touch screen overlay 18 . A partially translucent overlay 20 may be disposed between the LCD area 16 and the touch screen overlay 18 . As can be seen in FIG. 2 , touch screen overlay 18 may extend outside of the LCD area 16 so that permanent “fixed” buttons 22 may be provided for controlling main printer functions (on/off, label feed, setup, stop print, display statistics report, home button, and the like) underneath the touch screen overlay but outside of the LCD area (e.g., within the partially translucent layer). The partially translucent overlay 20 is transparent over the LCD area 16 , translucent at the fixed buttons 22 , and opaque everywhere else.
[0047] The fixed buttons 22 may be conditionally lit from behind by a controlled illumination device 24 (e.g., one or more LEDs or the like), which activates to indicate a certain state or feature of the button 22 . A bezel 26 may surround the touch screen overlay 18 .
[0048] The touch screen 12 may be provided with a configurable layout of buttons in the LCD area 16 (see, e.g., FIG. 4 ). Each touch screen layout may be created in a standard drawing or graphics program such as Visio and saved, for example as a standard Visio file. Through the “properties” feature of the drawing program, each graphic (button or other screen element) is assigned a class (e.g., “button”) with a related function call, so that when the button is pressed on the touch screen 12 , an action is defined (i.e., bring up a further screen identified by the button, increment an amount, print preview, change settings/configuration, edit/add items, and the like). Attributes of the buttons and other screen elements, such as color, size, font of text, shape, and the like are also assigned via the drawing program.
[0049] Once created, each screen layout is saved in a standard file (e.g., Visio) and downloaded to an SD micro card, which can then be inserted into a corresponding card reader on the printer or LCD controller. Firmware in the printer contains a lookup table which relates the function calls to the desired actions for each button and processes the corresponding screen changes. The following are representative of function calls and corresponding functions or actions that may be provided.
[0000]
{“ScrollUpMain”, ScrollUpMain,},
→ Advance display one
screen
{“ScrollDownMain”, ScrollDownMain,},
→ Go back one screen
{“DialogExit”, DialogExit,},
→ Exit current dialog/screen
{“ChangeCategory”, ChangeCategory,},
→ Change categorey
{“BrightnessUp”, BrightnessUp,},
→ Increase screen brightness
{“BrightnessDown”, BrightnessDown,},
→ Decrease screen brightness
{“CalibrateDialog”, LCDCalibrate,},
→ Calibrate touch screen
{“SelfTestDialog”, SelfTestDialog,},
→ Do a self test
{“SetLanguage”, SetLanguage,},
→ Change language
{“GoHome”, GoHome,},
→ Go to home screen
{“CharEntry”, CharEntry,},
→ Enter character into
memory
{“SetText”, SetText,},
→ Set text of screen element
{“ReDraw”, ReDraw,},
→ redraw the screen
{“SetFieldLen”, SetFieldLen,},
→ Limit field/element length
{“IncVal”, IncVal,},
→ Increment value of
memory element
{“SetUpperLimit”, SetUpperLimit,},
→ Limit hi value of
memory/screen element
{“SetLowerLimit”, SetLowerLimit,},
→ Limit lo value of
memory/screen element
{“SetList”, SetList,},
→ Set possible text values
{“Print”, Print,},
→ Display print dialog/screen
{“SetData”, SetData,},
→ Set memory element
{“InitPreview”, InitPreview,},
→ Init/draw print preview
{“GoToPage”, GoToPage,},
→ Go to page n of total
[0050] {NULL, NULL,}//end of table marker→End of table marker
[0000] In addition to invoking functions, parameters can be defined in Visio and passed to the corresponding function calls/invocations.
[0051] Thus, the screen layout is easily customizable by using a standard drawing program to manipulate each screen layout, and downloading the modified file to the printer. Once the screen layout file is downloaded to the printer, certain features of the screen may be further configurable via the touch screen itself, including button size, font selection, font size, and the like.
[0052] In addition, as shown in FIG. 4 , a print preview 30 of the label to be printed may be provided in the LCD area 16 of the touch screen 12 alongside a touch screen keypad 32 , providing the opportunity to view the label to be printed and input or modify information on the label to be printed (e.g., number of labels to be printed, expiration dates, or notes such as “Use First” or the like). Although FIG. 4 shows a numeric keypad 32 , it should be appreciated that the touch screen can also be configured to show an alphabet keypad or an alphanumeric keypad.
[0053] The touch screen 12 may be adapted to be pivoted or tilted back to provide direct access to the inside of the printer, facilitating paper loading. In other words, the touch screen 12 comprises a cover for the printer housing 40 , and opening of this cover gives access to the printer mechanism(s) and corresponding paper bucket(s).
[0054] An example of a first embodiment of a label printer 10 with a tilting touch screen 12 in accordance with the present invention is shown in FIGS. 5 and 6 . Although the Figures show a printer with two print mechanisms 34 and correspondingly separate paper rolls 36 , it should be appreciated that the features of the present invention can easily be implemented in a printer 10 having a single print mechanism. In addition, it should be appreciated that the paper source could be in the form of fan-folded tickets, rather than a paper roll or rolls.
[0055] FIG. 5 shows the printer 10 with the touch screen 12 tilted into the open position. In this embodiment, the print mechanisms 34 are contained in the touch screen housing (upper case) 39 and tilt up with the touch screen 12 . The platens 38 remain in the printer housing (lower case) 40 .
[0056] FIG. 6 shows a block diagram of the electronic architecture of the printer 10 shown in FIG. 5 . As can be seen in FIG. 6 , the touch screen overlay 18 is mounted on the LCD display 16 , and both the LCD display 16 and touch screen overlay 18 are in communication with the controller 42 (which may be, for example, a PCB mounted directly to the LCD Display 16 ). It is noted that FIG. 6 does not include the partially translucent overlay 20 of FIG. 3 , as the partially translucent overlay 20 is not part of the electronic architecture of the printer 10 .
[0057] The print heads, stepper motors, and top of form sensors for the corresponding print mechanisms 34 are also in communication with the controller 42 . Each of the touch screen overlay 18 , LCD Display 16 , controller 42 , and print mechanisms 34 are located in the touch screen housing 39 .
[0058] The SD micro card reader may be located on or in the controller board 42 (or otherwise connected thereto).
[0059] The printer housing 40 contains the paper buckets 44 and platens 38 connected to the touch screen housing 39 and the corresponding components located therein via mechanical interfaces 50 . The mechanical interfaces 50 may include guiding surfaces to orient the printheads into proper alignment with the printing platens. A spur gear transmission may be used to move power from the stepper motors to the platens.
[0060] The printer housing 40 may also contain a power supply 46 , and communication connectors 48 (such as USB ports, Ethernet ports, memory card readers, and the like), each of which is connected to the controller 42 .
[0061] In the embodiment shown in FIGS. 5 and 6 , all active electronics are located on the main controller 42 , which is mounted on the rear of the display module. The print heads, stepper motors, and sensors reside in the upper housing 39 , while the printer housing 40 contains only passive mechanical components, such as the paper buckets 44 and platens 38 . In the embodiment shown in FIG. 5 , the print heads are easily accessible for cleaning when the upper housing 39 is tilted open.
[0062] An example of a second embodiment of a label printer 10 with a tilting touch screen 12 in accordance with the present invention is shown in FIGS. 7 and 8 . Unlike the example embodiment described above in connection with FIGS. 5 and 6 , in the example embodiment shown in FIGS. 7 and 8 , the print mechanisms 34 do not tilt with the touch screen 12 and instead remain in the printer housing 40 .
[0063] FIG. 8 shows a block diagram of the electronic architecture of the printer 10 shown in FIG. 7 . As in the FIG. 6 embodiment, the touch screen overlay 18 is mounted on the LCD display 16 , and both the LCD display 16 and touch screen overlay 18 are in communication with the controller 42 (which may be, for example, a PCB mounted directly to the LCD Display 16 ). It is noted that FIG. 8 does not include the partially translucent overlay 20 of FIG. 3 , as the partially translucent overlay 20 is not part of the electronic architecture of the printer 10 .
[0064] However, unlike the FIG. 6 embodiment, as shown in FIG. 8 the print mechanisms 34 (including platen 38 ) are located in the printer housing 40 with the paper buckets 44 . A driver card 54 associated with the print mechanisms 34 may be provided which is in communication with the controller 42 via detachable flexible flat cables (FFC cables) 52 .
[0065] In the example embodiment shown in FIGS. 7 and 8 , the main controller 42 is mounted on the rear of the display module and includes logic outputs for driving the printer.
[0066] The print mechanisms 34 may be removable clamshell type print mechanisms mounted in the printer housing 40 . Only logic signals and raw power are sent over the FFC cables 52 from the controller 42 to the driver cards 54 to drive the print mechanisms 34 .
[0067] FIG. 9 shows a side view of the example embodiment of printer 10 shown in FIGS. 7 and 8 . As can be seen in FIG. 9 , the screen 12 when tilted does not extend beyond the back of the printer housing 40 , so that there is no interference with a mounting surface when wall mounted. Thus, the present invention enables flush mounting of the printer 10 against a wall, while still enabling full opening of the tilting screen 12 for direct access to the print mechanisms 34 and paper buckets 44 for service or paper loading, without requiring the removal of any additional covers.
[0068] FIG. 10A shows a perspective view of the printer with the touch screen 12 tilted into the open position. The touch screen housing 39 may be pivotally connected to the printer housing 40 by various means. As shown for example in FIG. 10A , the means may comprise pivot arms 41 fixed to the housing 39 . For example, an upper portion 37 of the pivot arm 41 may be secured to the inside of the housing 39 (i.e., via screws or bolts) on opposite sides of the housing. The pivot arm 41 may be pivotally secured to the printer housing 40 at a central pivot point 43 (e.g., via a pin, bolt, a recess and corresponding protrusion on the housing side panel 76 and arm 41 , or the like). A free end 45 of each arm 41 is resilient and has a protrusion adapted to springingly engage with or snap into corresponding recesses or pockets 47 , 49 provided in each side panel 76 of the printer housing 40 . When the touch screen 12 is tilted open as shown in FIG. 10A , the free end 45 of the arm 41 snaps into the lower recess 47 . When the touch screen is tilted down into the closed position, the free end 45 of the arm 41 snaps into the upper recess 49 .
[0069] Other conceivable means for enabling tilting of the touch screen 12 are conceivable and within the purview of the present invention. For example, the weight of the touch screen 12 may be supported by a torsion spring which will ease opening. As shown in FIG. 10B , the means may comprise a friction clutch assembly 35 , which serves to dampen the movement of the touch screen 12 (not shown in FIG. 10B ) during opening and closing. FIGS. 10C and 10D show an example embodiment where the means comprises counterbalancing friction hinges 31 which include a clutch assembly 35 having a torsion spring 33 . Two oppositely disposed counterbalancing friction hinges 31 may be provided on either side of the touch screen housing 39 and fixed to the housing side panels 76 of the printer housing 40 .
[0070] A more positive latching mechanism may be used to ensure a positive feel when pushing the touch screen housing 39 into the closed position. For example, as shown in FIG. 11 , the latching mechanism may comprise a magnet 51 and a corresponding metal striker plate 53 . FIG. 11 shows the magnet 51 arranged on a side of the inside of the touch screen housing 39 and a corresponding striker plate 53 on the housing side panel 76 . A similar arrangement may be provided on both sides of the printer housing 40 . One skilled in the art will appreciate that a single magnet and striker plate arrangement may be used or that the location may be changed. Further, it should be appreciated that the magnet 51 may be arranged on the housing side panel 76 and the striker plate 53 may be arranged on the touch screen housing 39 .
[0071] As can be seen in FIG. 1 , the power cord receptacle 90 and on-off switch 92 may be mounted to the printer housing 40 . A USB A port 94 , USB B port 96 , and Ethernet connection 98 may also be positioned in the printer housing 40 and connected to the controller board 42 . Additional ports (USB A and B, mini-USB and the like) may also be provided. Alternatively, these ports (e.g., USB A port 94 , Ethernet port 98 , and others) may be mounted directly to the controller board 42 through the touch screen housing 39 . For example, FIG. 13 shows a slideable cover 95 in the touch screen housing 39 covering the various ports.
[0072] FIGS. 12-16 show an example embodiment of a bracket 60 for mounting the printer 10 to a wall surface. FIG. 12 shows the bracket 60 unconnected to the printer housing 40 . The mounting bracket 60 is flat and designed for flush mounting of the printer 10 to a wall surface. The bracket 60 also enables the printer 10 to be mounted in two different positions on the bracket 60 so that the viewing angle of the touch screen 12 can be adjusted, as discussed in detail below. The bracket 60 is provided with through holes 61 for mounting screws for mounting the bracket to the wall.
[0073] An arm 64 extends from each side of the bracket 60 . The arms 64 may be provided with two slots 68 and 69 each. The arms 64 extend though slots 70 in the rear of the printer housing 40 .
[0074] FIG. 13 shows the printer 10 in a “full back” position where the printer 10 is positioned in slots 68 of arms 64 of the bracket 60 . FIG. 14 shows the printer in a “full forward” position where the printer 10 is positioned in slots 69 of arms 64 of the bracket 60 . This full forward position may position the printer at an angle with respect to the full back position, for example of approximately 30 degrees. It should be appreciated that additional positions and/or viewing angles may be provided by providing additional slots in arms 64 and/or by changing the length of the arms of the positions of the slots.
[0075] FIGS. 15 and 16 show the arms 64 extending through slots 70 into the interior of the printer 10 in the full back position and full forward position, respectively. As can be seen from FIG. 15 , in the full back position, the printer 10 sits in slots 68 of arms 64 . As can be seen from FIG. 16 , in the full forward position, the printer 10 sits in slots 69 of arms 64 . Thus, the printer can easily be installed on the bracket by aligning the slots 70 in the housing with the arms 64 , moving the printer towards the bracket 60 until the rear of the printer housing 40 is in alignment with the desired slots 68 or 69 , and lowering the printer 10 into the desired slots 68 or 69 . Removal of the printer 10 from the bracket 60 for servicing or re-positioning is the reverse process and entails simply lifting the printer 10 out of the slots and pulling the printer 10 away from the bracket 60 until the arms 64 of the bracket are free of the printer housing 40 .
[0076] Those skilled in the art will appreciate that various styles of brackets and arms may be used to mount the printer to the wall, including brackets with various positioning and adjustment options, brackets which enable pivoting of the printer with respect to the wall (in defined increments or at any position within an angel range), and the like.
[0077] Although the present invention has been described in connection with a label printer for printing freshness labels, the present invention is also easily adapted for use in other environments, including but not limited to as a label printer for a deli counter of a grocery store, as a label printer for a grill or beverage area of a fast-food restaurant, as a point-of-sale receipt printer, a barcode printer for inventory control and tracking, or the like. The printer can also be coupled with a scale through a USB interface. The system could then be used for weighing and labeling any kind of bulk goods.
[0078] It should now be appreciated that the present invention provides a food preparation printer with advantageous features, including but not limited to a small footprint, an easily configurable touch screen, easy serviceability, simplified paper loading, flush mounting, adjustable touch screen viewing angles, and more.
[0079] Although the invention has been described in connection with various illustrated embodiments, numerous modifications and adaptations may be made thereto without departing from the spirit and scope of the invention as set forth in the claims. | A method of configuring a touch screen for a printer and a configurable touch screen for a printer are provided. A touch screen layout is created using a standard graphics or drawing program. The touch screen layout is saved in a standard computer file. The computer file is loaded onto the printer or a controller of the printer which is in communication with the touch screen. The controller then configures the touch screen in accordance with the touch screen layout of the computer file. | 6 |
RELATED APPLICATIONS
This application is a continuation of U.S. Patent application Ser. No. 09/483,888, filed Jan. 18, 2000 now U.S. Pat. No. 6,377,318 by the same inventor, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
The present invention relates to the field of multi channel imaging devices, and more particularly to projection type imaging devices, wherein it is very important to accurately align physical components of the apparatus such that the color components of a resulting image will be aligned. The predominant current usage of the present inventive multi channel imaging engine is as a component of projection video display devices, wherein it is desirable to have a rugged and accurately aligned electro-optical unit for projecting well aligned color images therefrom.
BACKGROUND ART
The typical arrangement for multi-channel imaging systems will have a clamshell arrangement where the internal optics and components are assembled from above and the optical cavity is split along a horizontal plane into two halves. However, the construction of such a device results in two or more assembly planes. For example, at least one is horizontal for the placement of the splitting and combining optics, and at least one is vertical for the placement of the projection optics. This requires complex molded parts with expensive tooling. Since there are two or more assembly planes, the registration of the optics becomes more difficult. This problem is made worse in an off-axis design where the optics are not all on the same plane.
It would be desirable to have a multi-channel imaging system wherein the alignment problems discussed above are ameliorated. It would be of further benefit if such a device were sufficiently rigid to prevent distortion problems caused by flexing and vibration. However, such a solution, in order to be practical, should be inexpensive to produce and inexpensive to use in the production of a final multi channel image projection system.
To the inventor's knowledge, all previous apparatus or methods for producing a multi channel imaging engine have been difficult and/or expensive to manufacture and assemble, less than optimally rigid, and difficult to align and use.
DISCLOSURE OF INVENTION
Accordingly, it is an object of the present invention to provide a video projection engine that will provide sub-pixel accuracy over an entire image range.
It is still another object of the present invention to provide a video projection engine which is simple to construct and wherein components are readily aligned.
It is yet another object of the present invention to provide a video projection engine wherein there are no problems of mis-convergence due to twisting or bending of the optical housing.
It is still another object of the present invention to provide a video projection engine wherein artifacts from vibration introduced from external sources is minimized.
It is yet another object of the present invention to provide a video projection engine which is inexpensive to produce.
It is still another object of the present invention to provide a video projection engine which can be used with inexpensive auxiliary components.
It is yet another object of the present invention to provide a video projection engine which is inexpensive to install and align.
Briefly, an embodiment of the present invention is an assembly of mechanical components that aligns, supports and houses the optical, opto-mechanical and electronic components of a three color projection system. The architecture is executed in such a way that it solves many of the problems that are associated with high resolution multi-channel imaging systems. The total cost of the components is reduced because the number of components is less and the parts can be manufactured with high volume, low cost processes. The inter-channel stiffness and the mechanical stability between the individual color channels is superior to previous approaches. This is a direct consequence of the novel approach for enclosing the multi-channel cavity. There is no optical alignment required other than convergence of the discreet images. The components are all self-aligning with very low cost registration features.
The invention has a housing that is constructed in such a way that the entire optical cavity is contained inside the single formed part. The cavity is enclosed with a bulkhead that serves as a frame to align and support the optics and opto-mechanics. There is only a single assembly plane that is the plane of the bulkhead. The splitter and combiner optics are attached to the bulkhead as well as the projection lens. The cavity is enclosed when the kernel housing is attached to the bulkhead. The kernel housing can be formed as a single piece and there are no secondary operations required. The bulkhead can be stamped or molded and the bracket that holds the splitter dichroics, the combiner prism, the polarizer/analyzer assembly, and/or any additional optical devices can be molded (also with no secondary operations). There is a novel focussing mount for the projection lens that allows for a simple, low cost, fixed focus lens.
An advantage of the present invention is that a relatively inexpensive video projection engine is provided for incorporation into video projection imaging devices.
A further advantage of the present invention is that sub-pixel accuracy is provided over an entire image.
Yet another advantage of the present invention is that effects of vibration are essentially eliminated, such that cooling fans can be mounted on the video projection engine without adverse effects.
Still another advantage of the present invention is that the rigidity of the video projection engine essentially eliminates problems of mis-convergence due to twisting or bending of the optical housing.
Yet another advantage of the present invention is that the video projection engine is rugged in construction and reliable in operation.
Still another advantage of the present invention is that it is inexpensive to produce.
Yet another advantage of the present invention is that it is inexpensive to install, align, and use.
These and other objects and advantages of the present invention will become clear to those skilled in the art in view of the description of modes of carrying out the invention, and the industrial applicability thereof, as described herein and as illustrated in the several figures of the drawing. The objects and advantages listed are not an exhaustive list of all possible advantages of the invention. Moreover, it will be possible to practice the invention even where one or more of the intended objects and/or advantages might be absent or not required in the application.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is perspective view of a multi channel imaging engine according to the present invention;
FIG. 2 is an exploded perspective view of the multi channel imaging engine of FIG. 1 ;
FIG. 3 is an exploded perspective view of the lens unit of FIGS. 1 and 2 ;
FIG. 4 is an exploded perspective view of the bulkhead and the optical assembly of FIGS. 1 and 2 ;
FIG. 5 is an exploded perspective view of the optical assembly of FIGS. 1 , 2 and 4 ;
FIG. 6 is a perspective view of another embodiment of a multi channel imaging engine according to the present invention; and
FIG. 7 is an exploded perspective view of the example of the multi channel imaging engine of FIG. 6 .
DETAILED DESCRIPTION OF THE INVENTION
The embodiments and variations of the invention described herein, and/or shown in the drawings, are presented by way of example only and are not limiting as to the scope of the invention. Unless otherwise specifically stated, individual aspects and components of the invention may be omitted or modified, or may have substituted therefore known equivalents, or as yet unknown substitutes such as may be developed in the future or such as may be found to be acceptable substitutes in the future. The invention may also be modified for a variety of applications while remaining within the spirit and scope of the claimed invention, since the range of potential applications is great, and since it is intended that the present invention be adaptable to many such variations.
The mode for carrying out the invention, as described herein, is a multi channel imaging engine. An example of the inventive multi channel imaging engine is depicted in a perspective view in FIG. 1 and is designated therein by the general reference character 10 . The multi channel imaging engine 10 has a housing 12 with a lens cradle 14 affixed thereto. The lens cradle 14 supports a lens assembly 16 which is held in place, thereon, by a lens retainer 18 . The assembled lens cradle 14 , lens assembly 16 , and lens retainer 18 will be referred to, herein, as a lens unit 19 .
This example of the invention has two cooling fans 20 affixed to the housing 12 . While the cooling fans 20 are not a necessary part of the invention, it is instructive to note that the present inventive multi channel imaging engine 20 is sufficiently rigid that the cooling fans 20 can be mounted thereon without the adverse effects of vibration which would result from a less rigid device.
In this embodiment of the invention, the housing 12 has a kernel housing 22 and a bulkhead 24 . The kernel housing 22 described herein is die cast from aluminum alloy, although other construction techniques including but not limited to alternative molding methods are within the scope of the invention. Another example of a construction technique would be to press form the housing from a single piece of sheet steel, or to cut and bend sheet metal into the desired shape. The bulkhead 24 is affixed to the kernel housing 22 by screws 26 , as shown by way of example in the view of FIG. 1 such that an interior 27 of the housing 12 is generally enclosed by the bulkhead 24 and the kernel housing 22 .
An optical assembly 28 is affixed to the bulkhead 24 within the housing 12 , and three LCD assemblies 30 are affixed to the outside of the housing 12 . The LCD assemblies 30 may optionally be of essentially any reflective type, wherein light projected onto one of the LCD assemblies 30 is modified according to an image electronically provided to the LCD assembly and the light, modified to conform to the image, is reflected therefrom. One skilled in the art will be familiar with such devices. In this present embodiment of the multi channel imaging engine 10 , the LCD assemblies 30 are of the commercially available type. The LCD assemblies 30 are each affixed to the kernel housing 22 using an alignment mount 32 whereby the LCD assemblies 30 may be aligned, as necessary, during final assembly of the multichannel imaging engine 10 . One skilled in the art will also be familiar with the alignment mount 32 , and variations of such that are available.
FIG. 2 is an exploded perspective view of a portion of the multichannel imaging engine 10 of FIG. 1 . In the view of FIG. 2 , it can be seen that the optical assembly 28 is affixed to the bulkhead 24 . Also, in the view of FIG. 2 it can be seen that the lens cradle 14 has an additional plurality (three are visible in the view of FIG. 2 ) of the screws 26 for affixing the lens cradle 14 to the bulkhead 24 .
A light entry port 34 can be seen in the bulkhead 24 wherethrough white light is introduced into the housing 12 . Also visible in the view of FIG. 2 are two of the three LCD ports 36 wherethrough light is projected onto, and reflected form the LCD assemblies 30 (FIG. 1 ). One of the two cooling ports 38 of this embodiment of the invention, whereon the cooling fans 20 ( FIG. 1 ) are affixed, is also visible in the view of FIG. 2 .
FIG. 3 is an exploded perspective view of the lens unit 19 , previously discussed herein in relation to FIGS. 1 and 2 . The fixed focus lens assembly 16 has a positioning projection 40 , and the lens cradle 14 has two retaining rings 42 for accepting the lens assembly 16 . Each of the retaining rings 42 has a gap 44 therein such that the lens assembly can be inserted into the lens cradle 14 with the positioning projection 40 aligned with the gaps 44 . The lens assembly 16 is then secured in position in the lens cradle 14 by the lens retainer 18 using a pair of cap screws 46 . As can be seen in the view of FIG. 3 , a positioning slot 48 in the lens retainer 18 is angled such that, when the positioning projection 40 is within the positioning slot 48 , the rotating the lens assembly 16 (with the cap screws 46 appropriately loosened), as indicated by arrow 50 , will cause the fixed focus lens assembly 16 to move forward or backward in the lens cradle 14 , as indicated by arrow 52 , such that the lens assembly 16 can be focused, as required.
FIG. 4 is an exploded view of the bulkhead 14 and optical assembly 28 wherein the optical assembly 28 can be more readily viewed. As can be seen in the view of FIG. 2 , an output truncated doublet 54 (which is effectively used as a prism for redirecting light) of the optical assembly 28 projects partially through a light exit port 56 in the bulkhead 14 when the optical assembly 28 is affixed to the bulkhead 14 . Also visible in the view of FIG. 4 are a dichroic mirror assembly 58 , and a color cube 60 , which will be discussed in more detail, hereinafter. The output truncated doublet 54 , the dichroic mirror assembly 58 and the color cube 60 are each affixed to an optical frame 62 .
FIG. 5 is an exploded perspective view of the optical assembly 28 , according to this presently described embodiment of the invention. One skilled in the art will recognize that the dichroic mirror assembly 58 has three dichroic mirrors 64 arranged in an “X” configuration such that white light projected onto the dichroic mirror assembly 58 is divided into its three basic component wavelength colors, with one of each such colors being directed toward a corresponding one of the LCD assemblies 30 (FIG. 1 ). One skilled in the art will also recognize that the color cube 60 is made up of four color cube prisms 65 with the contiguous surfaces thereof having dichroic surfacing such that three primary color light beams reflected from the three LCD assemblies 30 are recombined and directed toward the output truncated doublet 54 .
It is important to note that, in this embodiment of the invention, light us directed slightly upward (from a perspective where the color cube 60 is above the dichroic mirror assembly 58 ) as light enters the housing 12 through the light entry port 34 (FIG. 2 ), as indicted by a light input path arrow 66 in FIG. 1 . Accordingly, as light travels through the multi channel imaging engine 10 , the light is divided by the dichroic mirror assembly 58 , modified by and reflected from the LCD assemblies 30 , and recombined by the color cube 60 relative to a first plane 68 . The light is also moving relative to a second plane 70 (generally upward, as discussed previously herein) such that the light first passes through the dichroic mirror assembly 58 , is then reflected at an upward angle from the LCD assemblies 30 , and then passes through, and is recombined by, the color cube 60 . Since an optical axis 72 of the lens assembly 16 is aligned generally along the first plane 68 , the output truncated doublet 54 is shaped and configured to realign the (slightly upward canted) light with the optical axis 72 of the lens assembly 16 .
Accordingly, the described embodiment of the multi channel imaging engine 10 is assembled generally as follows; The optical assembly 28 is assembled as described herein and affixed to the bulkhead 24 . The bulkhead is affixed to the kernel housing 22 generally enclosing the interior 27 thereof. The LCD assemblies 30 are affixed to the exterior of the kernel housing 22 , using the alignment mounts 32 , as previously described herein. In this manner, the bulkhead 24 and the kernel housing 22 serve as mounting means for mounting the optical assembly 28 with respect to the LCD assemblies 30 . Except as otherwise stated, or as may be necessitated by a particular application or variation of the invention, the order of assembly operations is not critical and is not an inherent part of the invention.
Another embodiment of the multi channel imaging engine is depicted in a perspective view in FIG. 6 and is designated therein by the general reference character 10 a . This embodiment of the multi channel imaging engine 10 a is not greatly different in kind and in components from the previously described multi channel imaging engine 10 , previously described herein. The multi channel imaging engine 10 a is presented here in order to illustrate some possible variations in shape and construction as described herein and as depicted in the drawings. As can be seen in the view of FIG. 6 , the multi channel imaging engine 10 a has a housing 12 a with a lens cradle 14 a affixed thereto. The lens cradle 14 a supports a lens assembly 16 a which is held in place, thereon, by a lens retainer 18 a . The assembled lens cradle 14 a , lens assembly 16 a , and lens retainer 18 a will be referred to, herein, as a lens unit 19 a . As can be seen in the view of FIG. 6 , two of the cooling fans 20 are affixed to the housing 12 a in this embodiment of the invention, as well.
In this embodiment of the invention, also, the housing 12 a has a kernel housing 22 a and a bulkhead 24 a , each of which are constructed by methods similar to those previously described in relation to the first described embodiment of the invention, herein, and shaped as shown in the view of FIG. 6 and the subsequent figures of the drawing.
An optical assembly 28 a is affixed to the bulkhead 24 . within the housing 12 a , and three LCD assemblies 30 , which are not significantly different from the LCD assemblies 30 previously described herein, are affixed to the outside of the housing 12 a . The bulkhead 24 a and the kernel housing 22 a when fixed to each other, provide mounting means for mounting the optical assembly 28 a with respect to the LCD assemblies 30 .
FIG. 7 is an exploded perspective view of a portion of the multichannel imaging engine 10 a of FIG. 6 . In the view of FIG. 7 , it can be seen that the optical assembly 28 a is affixed to the bulkhead 24 a . Indeed, in this embodiment of the multi channel imaging engine 10 , the components of the optical assembly 28 a are affixed directly to the bulkhead 24 a , as will be discussed in more detail, hereinafter. In this embodiment also, a light entry port 34 a can be seen in the bulkhead 24 a wherethrough white light is introduced into the housing 12 a . Also visible in the view of FIG. 7 are two of the three LCD ports 36 a wherethrough light is projected onto, and reflected form the LCD assemblies 30 (FIG. 6 ). One of two cooling ports 38 a of this embodiment of the invention, whereon the cooling fans 20 ( FIG. 6 ) are affixed, is also visible in the view of FIG. 7 . The fixed focus lens assembly 16 a , the lens cradle 14 a , and the lens retainer 18 a function much like the fixed focus lens assembly 16 and the lens cradle 14 previously discussed herein in relation to FIG. 3 , although the actual shape is somewhat different, as can be seen by comparison of the views of FIGS. 2 and 7 .
As can be seen in the view of FIG. 7 , an output doublet 54 a is positioned in relation to a light exit port 56 a , and performs functions previously as described herein in relation to the truncated doublet 54 of the previously described embodiment.
In this presently described embodiment 10 a of the present invention, the dichroic mirrors 64 are assembled within a mirror receptacle 74 which is formed as a part of the bulkhead 24 a , and the color cube 60 is affixed to the bulkhead 24 a . The dichroic mirrors 64 and the color cube 60 are essentially the same as, and function in an similar manner to like elements previously discussed herein in relation to the first described embodiment 10 of the invention.
Various modifications may be made to the invention without altering its value or scope. For example, the housing 12 could be molded and/or made from another material.
All of the above are only some of the examples of available embodiments of the present invention. Those skilled in the art will readily observe that numerous other modifications and alterations may be made without departing from the spirit and scope of the invention. Accordingly, the disclosure herein is not intended as limiting and the appended claims are to be interpreted as encompassing the entire scope of the invention.
INDUSTRIAL APPLICABILITY
The inventive multi channel imaging engine 10 is intended to be widely used in the production of video image projection systems such as high resolution projection television devices, and particularly computer video output projection display devices. The invention allows convergence to sub-pixel accuracy over the entire image. The assembly is simplified by the self-aligning features and there is no alignment of optics other than the convergence of the three image channels. The inter-channel stiffness is substantially high so that there are no problems of misconvergence due to twisting or bending of the optical housing. There is a substantial cost advantage because the construction of the mechanics allows for simple molded and stamped parts with no secondary machining operations. The focussing mount can be molded and allows the projection lens to be purchased as a low cost fixed focus lens.
This mechanical architecture is a departure from the typical method of projection system assembly. It permits low cost system solutions, especially with (but not exclusive to) off-axis projection systems. This will allow off-axis reflective projection systems to complete effectively in the market for high resolution, low cost display systems.
One skilled in the art will readily understand the alignment procedures used in conjunction with the present invention. For example, the alignment mounts 32 are used to adjust the LCD assemblies such that the three color component images properly align when recombined in the color cube 60 . Similarly, the lens retainer 18 will be loosened and the lens assembly rotated, as briefly discussed herein before, to properly adjust the focal aspect of the lens assembly 16 .
Since the multi channel video projection engine 10 of the present invention may be readily produced and integrated with existing video creation and display systems and devices, and since the advantages as described herein are provided, it is expected that it will be readily accepted in the industry. For these and other reasons, it is expected that the utility and industrial applicability of the invention will be both significant in scope and long-lasting in duration. | A multi channel video engine ( 10 ) for accepting, dividing, modifying and recombining light to project an image. A housing ( 12 ) encloses an optical assembly ( 28 ) having a dichroic mirror assembly ( 58 ) and a color cube ( 60 ). A plurality of LCD assemblies ( 30 ) accept light from the dichroic mirror assembly ( 58 ), modifies it, and reflects it to the color cube ( 60 ). A lens assembly ( 16 ) is affixed to a bulkhead ( 24 ) of the housing ( 12 ) using a lens cradle ( 14 ) and lens retainer ( 18 ). An output prism ( 54 ) aligns light onto a second plane ( 70 ) to coincide with an optical axis ( 72 ) of the lens assembly ( 16 ). | 7 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority under Title 35, United States Code §119 of U.S. Provisional Application Serial No. 60/305,336, filed Jul. 13, 2001.
TECHNICAL FIELD
[0002] This invention relates to improved sealing and operational reliability of reciprocating gas compressor valves. More specifically, this invention is directed to the use of elastomeric material in connection with a sealing element of a reciprocating gas compressor valve to produce a reliable, durable seal.
BACKGROUND OF THE INVENTION
[0003] Reciprocating gas compressors are equipped with valves that open and close to intake and expel gases. Often such valves alternate open and close with each revolution of the compressor crankshaft and there are a very large number of suction and discharge events per minute. As a consequence, the valve must be designed to tolerate a high level of repetitive stress. The sealing element of the valve establishes a seal between it and the opposing, fixed seating surface. Without proper sealing, hot discharged gas leaks back into the cylinder and temperatures escalate from recompression of the gas. Hence, the overall throughput, reliability, efficiency and revenue generating ability of the reciprocating gas compressor are diminished.
[0004] While the valves in a reciprocating gas compressor are of various types and forms, each valve has a seating surface, a moving sealing element, a stop plate and mechanism to force the valve elements to close before the compressor piston reaches top or bottom dead center. The sealing element is pressed against the corresponding seating surface to close the valve by a combination of spring forces and differential pressures. The differential pressures are considerably larger in magnitude than the spring forces. An example of a typical reciprocating gas compressor valve is described in commonly assigned U.S. Pat. No. 5,511,583 to Bassett.
[0005] During the operation of the valve, the seating surface and the sealing element may be damaged by impact from liquids or solids entrained in the gas stream. Furthermore, operating conditions may vary in such a way that the sealing element strikes the seating surface at velocities higher than design tolerances of the sealing element or the seating surface. In other words, the forces generated cannot be tolerated by the sealing element. In such cases, the force of impact may cause fractures in the sealing element, accelerated wear in the sealing element and/or seating surface, and recession of the sealing areas of the sealing element. The recession phenomenon is particularly evident in sealing elements made of thermoplastic or metallic materials. Many traditional materials currently used do not have the ability to dissipate the energy resulting from high impact velocities, or entrained dirt and liquids and this may lead to premature failure of the ability of the reciprocating gas compressor valve to provide a gas tight seal.
[0006] When the sealing element or the seating surface is damaged and the ability to form a gas tight seal is lost, the valve or component elements must be replaced or refurbished. Additionally, in many cases such valve failures may be catastrophic in nature and result in damage to other parts of the reciprocating gas compressor or downstream equipment. Therefore, the longevity of the seal between the sealing element and the seating surface results in an increase in the useful life of the reciprocating gas compressor valve as measured by the mean time between failures of the reciprocating gas compressor valve.
[0007] The sealing elements of reciprocating gas compressor valves have historically been made of metal. However, rigid thermoplastic materials were introduced in the early 1970's. Both materials are used today. These stiff, non-elastomeric materials require a fine machine finish and are often lapped in order to further reduce surface defects. The contact surface of the seat may be flat or shaped in a manner that mimics the surface contours of the moving sealing element.
[0008] When using a metal, thermoplastic material, or other rigid material as the sealing element, for the seal to be fully gas tight, the surfaces of the sealing element and particularly the sealing surface must be smooth and free from defects. In any machining operation, the cost and time required for manufacture are directly related and proportional to the surface finish required. Tighter tolerances require machine tools that are more precise and expensive. If there are defects in the sealing of a valve, gas will leak through the valve, component temperatures will elevate and the reciprocating gas compressor will operate in a highly inefficient manner. Furthermore, once the sealing integrity of the compressor valve has been compromised, the reciprocating gas compressor must be shutdown for the repair or replacement of the reciprocating gas compressor valves.
[0009] Rigid thermoplastic materials are often filled or blended with glass fibers and other materials in order to create the properties necessary for the service conditions. The method of molding and mold design can be critical for properly aligning fibers. Furthermore, proper alignment of fibers is critical to strength and/or mechanical properties of the sealing element. Moreover, poor mold flow characteristics weaken the sealing element and make it susceptible to failure from stress raisers in the material.
[0010] Injection molding of thermoplastics requires special mold and competent mold design in order to alleviate the problems of rigid thermoplastic materials. Thermoplastic materials create wear in a mold as the plastic and abrasive fillers (e.g., glass) flow through the internal passages. Repairing or replacing a mold adds to the overall expense of the manufacturing operation.
[0011] Metal parts require rather stringent dimensional and surface finish tolerances. Machine tools capable of generating such tolerances are generally more expensive and more time is always needed to create the sealing element. This is true for thermoplastic parts as well. For example, metal sealing elements require lapping and must be put on a separate machine to be lapped to the required surface finish. Time and expense are added to the process.
[0012] Quality control of rigid components is a key step in the successful operation of the parts. Dimensional conformance must be monitored and inspected regularly to ensure a consistent product. Thermoplastic parts are susceptible to water absorption, causing swelling and dimensional changes even during storage. The changes are often severe enough to render the parts unusable. Metal parts can rust and pitting can occur that destroys the fine finishes. Parts that are mishandled or allowed to collide with other hard objects during shipment can make them unusable. This adds to the warranty loss of the supplier.
[0013] There are an infinite number of operating conditions that exist. The variables include temperature, speed, impact or shock damage during opening and closing, pressure, gas constituents, and the amount of entrained dirt and or liquids in the gas. The service life of a valve is typically inversely proportional to the amount of debris (liquid or solid) in the gas stream. As particles strike the fine surfaces of the sealing element, damage to the valve degrades its ability to establish a gas tight seal. Recovery of the gas tight seal is not possible unless the sealing element of the valve is replaced or refurbished.
[0014] Due to disruptions in service conditions and due to the nature of the motion of the sealing elements during operation, the brittle metals and thermoplastics may suffer chipping of the edges. Chipped surfaces often lead to fractures and subsequent failure of the valve whereby the sealing elements fracture into one or more parts. Total replacement of the valve is then necessary.
[0015] A need exists, therefore, for a sealing element that efficiently seals a reciprocating gas compressor valve for the purpose of improving reliability and durability.
SUMMARY OF THE INVENTION
[0016] The present invention is a reciprocating gas compressor valve comprising a sealing element made of and having at least one layer of elastomeric material. The sealing element may have a single layer or multiple layers of elastomeric material or be entirely elastomeric material.
[0017] The novel use of elastomeric materials in reciprocating gas compressor valves provides the following benefits. First, the inherent property of elastomers to flex and conform to irregular or damaged surfaces produces a gas tight seal over a variety of damaged or undamaged surfaces. In short, the use of elastomers provides greater confidence that a gas tight seal is established even when the sealing surfaces are not smooth or in perfect condition. Second, the use of elastomeric material eliminates the process of lapping the sealing surfaces. Most valves and valve designs make use of lapping to create or restore sealing surfaces. Lapping produces the fine finishes necessary to establish a gas tight or near gas tight seal in the current state of the art. Surface finishes possible by present day machining technology can easily generate a surface finish that can be sealed with an elastomer part. A great deal of manual labor and additional production costs can be eliminated. Third, since elastomeric material can be attached to nearly any form or geometry, sealing element shapes that are more aerodynamic than the current state of the art are now possible. Designing more aerodynamics shapes lowers pressure drops through the valve. Fourth, elastomers can flex and conform, and machining tolerances can be relaxed. This is a direct cost saving to the production of the parts. Current compressor valve technology requires rather tight machining tolerance in order to assure a gas tight seal. Fifth, elastomeric material may be designed to have a density less than the density of the rigid substrate of the sealing element. Therefore the parts coated are less massive and less massive parts make for less destructive collisions when the valve element makes contact with the valve seat at the time of closing. Simply having less mass means that impact energies are reduced and the parts will suffer even less damage during the closing event. Sixth, elastomeric sealing elements are relatively easy to make and cost competitive. Tight tolerances are less important. Therefore, complicated shapes can be made and the elastomer can be applied as a final step. Seventh, since elastomeric materials may be formulated in a nearly infinite number of ways, those skilled in the art have nearly as many possible solutions to a particular compressor valve performance problem. Eighth, elastomeric materials are a source for improved plant efficiency and a source for increase revenue generating capability for users of reciprocating gas compressors. Uninterrupted operation for longer periods of time means more revenues and lower maintenance cost for the end user. Ninth, elastomeric material dissipates impact energies better during the closing events. Currently used non-resilient materials lack this property and the ability of the valve to form a gas tight seal for extended periods of time diminishes. Finally, because elastomeric materials can better tolerate the impact energy at the closing event of gas compression, it will be possible to permit valve elements to operate with far more travel than current technology will allow. The capability of being able to open the valve more fully will further reduce pressure drops (losses through the valve) and improve operating efficiencies.
[0018] Sealing elements come in a variety of shapes. There are many reasons for the different shapes, but primarily the goal is to 1) improve the aerodynamics as the gas passes over and around the element and through the valve; 2) improve the strength of the part to make it less susceptible to the rigors and upsets of the operating conditions; and 3) create a real or perceived differentiation between manufacturers in order to improve sales. Furthermore, in spite of the variety of shapes, all current valve designs suffer from damage by entrained dirt and liquids in the gas stream and the accumulated wear of a large number of opening and closing events. The present invention makes use of the inherent properties of elastomeric materials to overcome this weakness of conventional materials.
[0019] The sealing element of the subject invention may be useful in any reciprocating gas compressor where gases are compressed at virtually any pressure and temperature. The reciprocating gas compressor valve may be of any shape or size and may contain any number of sealing elements. Moreover, the sealing element may be offered as a replacement/upgrade to existing equipment or as a new part in new equipment.
[0020] As used herein, elastomeric material means a material or substance having one or more elastomers, an elastomeric compound or compounds used together, or a combination of elastomer or elastomeric compounds with other substances. The elastomeric material used in connection with the subject invention does not have to be a single type of elastomer, but may be a compound or combination of substances as described below. Hence, the sealing element may be made entirely of elastomer or as a composite where the elastomer may be bonded to or combined with other materials for improved mechanical properties.
[0021] Elastomers or elastomeric materials suitable for use in connection with the subject invention include any of various elastic substances resembling rubber such as synthetic rubbers, fluoro-elastomers, thermoset elastomers and thermoplastic elastomers. Elastomers have, by definition, a certain level of elasticity, that is, the property by virtue of which a body resists and recovers from deformation produced by force. Hence, the elastic limit of such material is the smallest value of the stress producing permanent alteration. Elastomers have the inherent ability to dissipate energy from shocks and collisions.
[0022] The elastomeric material may be varied as necessary to satisfy the operating conditions of a particular application. Softer or harder compounds may be required or different mechanical properties may be required to meet the various service needs experienced by the reciprocating gas compressor valve. In addition, corrosion resistance and chemical attack may mandate different material blends. One skilled in the art will rely on experience and published data to make a proper material selection.
[0023] The hardness of elastomeric material is typically measured using the “Shore” scale. The Shore scale was developed for comparing the relative hardness of flexible elastomeric materials. The unit of measure is the “durometer”. An analogous scale would be the “Rockwell” or “Brinell” scales used in measuring the hardness of metals.
[0024] The use of elastomeric material as the sealing element of a reciprocating gas compressor valve has a number of benefits. One important benefit is a better gas tight seal within the reciprocating gas compressor. Elastomeric materials by their nature flex and conform to surfaces that they come into with. Hence, a second benefit is a durable, gas tight seal with irregularities in the seat surface. Another benefit is that the elastomeric material absorbs shock or the forces between the sealing element and the seat, reducing the potential of impact damage of either element and increasing the useful life of the compressor valve. The elastomeric material is also resilient so as to minimize the damage caused by entrained liquids or solid debris that may be in the gas stream. Time between reciprocating gas compressor valve failure is increased. Other benefits of the invention will become clear from the description of the invention.
[0025] Still other objects, features, and advantages of the present invention will be apparent from the following description of the preferred embodiments, given for the purpose of disclosure, and taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] [0026]FIG. 1A is a top view of a sealing element for a ported plate valve.
[0027] [0027]FIG. 1B is a cross sectional view of the sealing element for the ported plate valve of FIG. 1.
[0028] [0028]FIG. 2 is a cross sectional view of a sealing element for a ported plate valve.
[0029] [0029]FIG. 3 is a cross sectional view of a sealing element for a concentric ring valve.
[0030] [0030]FIG. 4A is a cross section view of a sealing element for a concentric ring valve.
[0031] [0031]FIG. 4B is the sealing element of FIG. 4A depicting a line contact between the sealing surface and the sealing element.
[0032] [0032]FIG. 5A is a cross section view of a sealing element for a single element non-concentric ring valve.
[0033] [0033]FIG. 5B is the sealing element of FIG. 5A depicting a surface contact between the sealing surface and the sealing element.
[0034] FIGS. 6 A-H is a side view of various types of sealing elements used in a single element non-concentric ring valve also known as poppet valves.
[0035] [0035]FIG. 7A is a schematic of a typical gas compressor.
[0036] [0036]FIG. 7B is a front view of the typical gas compressor of FIG. 7A.
[0037] [0037]FIG. 8 is a two dimensional graph depicting deflection of a sealing element when subjected to a pressure load.
[0038] [0038]FIG. 9 is a two dimensional graph depicting deflection of a sealing element when subjected to a pressure load.
DETAILED DESCRIPTION OF THE INVENTION
[0039] The subject invention is a sealing element 30 of a reciprocating gas compressor valve having at least one elastomeric layer 32 made from an elastomeric material. “Gas” as used herein means any compressible fluid. The sealing element may have multilayers of elastomeric material, or may be constructed entirely of elastomeric material. The elastomer layer 32 may be a coating applied to the sealing element 30 using bonding materials in a variety of methods well known in the relevant art. The bonding and primer agents are commercially available.
[0040] For example, one bonding material used in connection with the subject invention that bonds Mosites fluoroelastomer to a PEEK substrate is a commercially available product known as Dynamar 5150. Bonding is improved by the addition of an epoxy adhesive known as Fixon 300301, a two-part epoxy. Fixon was applied at the time the elastomeric material was compression molded and after the primer, Dynamar 5150, was applied and dried on the PEEK substrate. Another bonding material used to bond 58D urethane to a PEEK substrate is known as PUMTC405TCM2, a proprietary bond/primer provided by Precision Urethane.
[0041] The ability of elastomeric materials to bond to other materials varies and depends on a number of factors. Generally, elastomers will adhere to a surface that is clean and dry. Therefore, a degreasing operation using a volatile commercial solvent by wiping or spraying the surface may be necessary. Surface adhesion can be modified by sand/bead blasting, scratching with sandpaper or by eliminating the fine surface finish requirements of the non-elastomeric part. By roughing the surface, more surface area is provided for elastomer bonding. Bonding between elastomeric and non-elastomeric parts can be achieved or enhanced by coating the non-elastomeric part with a primer that is compatible with both materials. The purpose of the primer is to react chemically or thermally with the two materials to improve or create the bond. These bonding procedures have been described using one elastomer and one non-elastomer, but may be used for any number of materials metallic and nonmetallic in the composite form.
[0042] Currently, reciprocating gas compressor valves utilize several types of sealing elements. As shown in FIGS. 1, 2, 3 and 6 , three common forms of valves used in reciprocating gas compressors are: concentric ring (FIG. 3), single element non-concentric (FIG. 6) and ported plate (FIGS. 1 and 2). Concentric rings are typically set equal in distance from one another, but the distance between rings may or may be not fixed and can vary depending on the manufacturer. The distance between the rings depends on the design of the valve. Concentric rings may be simply flat plate with a rectangular cross section or they be made into special shapes (non-rectangular cross sections) for the purposes of achieving better aerodynamic efficiency or an improvement in the longevity of the seal. Metallic or non-metallic materials are common. U.S. Pat. No. 3,536,094 to Manley teaches a concentric ring type of valve.
[0043] Ported plate valves are very similar to concentric ring valves in that there are multiple rings but the rings are all connected via narrow webs. The effect is to create a single sealing element of interconnected concentric rings. An example of a ported plate valve can be found in U.S. Pat. No. 4,402,342 to Paget. The sealing element of the ported plate valve may be nearly any size and geometry. However, in almost all cases, the sealing element of the ported plate valve is flat on both sides and has areas machined out where gas is intended to flow. Machining out the areas where the gas flows essentially creates the webs that interconnect the concentric ring of the plate. Some manufacturers create molds to produce the finished sealing element in an attempt to reduce machining costs. Opinions vary as to whether molding the sealing element of the ported plate produces a quality part in terms filler or fiber alignment in the finished product.
[0044] Some of the advantages of the ported plate are that the springs that support the sealing element act on the entire sealing element rather than just the ring under which they are placed. Since the rings are all connected, the design permits the use of larger and possibly fewer springs than a valve with concentric rings that are not all connected. In non-connected concentric ring valves, the individual rings are supported by their own springs and generally the diameter of the springs is limited to the width of the particular sealing element or ring.
[0045] Ported plate valves operate in a slightly different manner than non-connected types. While the basic function is the same (to alternately open and close), the gas dynamics in the reciprocating gas compressor cylinder are such that flow through a compressor valve is rarely perfect. In other words, because of the various geometries of the gas compressor cylinders themselves, the gas forces acting on the ported plate may not be equally distributed across the entire plate and one side of the plate may open ahead of the other side. The sealing element may tip to some angle rather than moving in a motion that is purely perpendicular to the sealing surface. While this is not necessarily detrimental to performance, the sealing element the strikes the guard or stop plate or sealing surface at some angle other than perpendicular can suffer edge chipping which can lead to fractures of the ported plate valve. Conversely, concentric ring valves are less susceptible to the problems associated with edge chipping but it does occur. The operation of the concentric ring valve permits the individual rings to operate independently of one another. Opinions vary as to which functions better but they are both widely used and are very effective designs.
[0046] Ported plate valves and concentric ring valves are generally known to have rather large flow areas and lower pressure drops, representing efficiency advantages. However ported plate valves, by their nature, are difficult to form into aerodynamic shapes. What cannot be achieved with improved aerodynamics is achieved with more generous flow areas. Concentric rings as used in the MANLEY® valve can be made into aerodynamic shapes and the minor loss in flow area can be restored with better aerodynamics. The function is the same, but the path to achieve it is slightly different.
[0047] On the other hand, single element, non-concentric valves do not usually suffer from edge chipping because the diameter of the elements is small and guides within the valve seat or guard prohibit the element from tipping far enough for edge chipping to be a problem. The potential for edge chipping increases with diameter. Single element, non-concentric valve elements can be made into aerodynamic shapes as well.
[0048] The single element non-concentric type of valve includes the poppet type of valve shown in FIG. 6, and the MOPPET® valve as shown and described in U.S. Pat. No. 5,511,583 and other valves where the sealing element has a shape that fits into the available area of the valve seat. The diameter of the valve and the size of the sealing element determine the number of elements that can be fitted into the available area. A wide variety of shapes and element cross sections are available and depend on manufacturer design. Often use of single element, non-concentric element types have a single spring device that controls its motion as opposed to a concentric ring design in which a single ring or plate is supported by a number of springs. As noted the purpose of the spring is designed to close or to begin to close the sealing element before the piston reaches top or bottom dead center. Differential pressure opens and closes the valve. Springs are relevant to the dynamics of the valve element motion and they are a critical component in the valve; however, they are not relevant to the sealing characteristics of the valve elements. When the valve is in actual service, differential pressure forces dwarf the spring forces.
[0049] While the valves may vary in structure, the function of the sealing element of any type of valve is to create a reliable gas tight seal after each closing event of the valve after many repetitions. The sealing element used in any type reciprocating gas compressor valve serves the same function. In spite of the differences in geometry and design, all valve elements are made to: a) produce a gas tight seal when the valve is in the closed position; b) survive the rigors of successive impacts with the sealing surface when the valve changes from open to a closed position; c) survive and tolerate as much as possible impacts and damage caused by liquids and or solid debris entrained in the gas stream; d) seek to increase the mean time between valve failures so as to minimize unscheduled compressor shutdowns for valve repair where doing so increases revenue potential for the operator of the compressor and lowers operating costs; e) be cost effective; f) be easy to install and minimize the time needed to repair or refurbish; and g) be aerodynamic so as to minimize pressure drops (losses) as the gas flows through the valve. Pressure drops are essentially “friction” that must be overcome by the reciprocating gas compressor driver. Reducing pressure drops increases operating efficiencies by saving fuel and/or electricity.
[0050] Hence, sealing elements able to perform for long periods of time and over many cycles are considered reliable and are desired as the operating availability of the compressor is improved. Fewer unscheduled equipment failures reduce operating costs for the equipment and increase the revenue generating ability of the equipment. Noteworthy, surfaces other than the sealing surface and the sealing element make contact during opening events. Therefore, impacts and damage may occur not as a result of the impact of the sealing element. Surfaces that collide during the opening event do not influence or degrade the ability of the valve to seal unless the valve element should fracture or otherwise lose its shape.
[0051] The elastomeric materials to be used in connection with the sealing element of the subject invention include, but are not limited to, natural rubber, styrene butadiene, synthetic rubber, and polymers such as thermoplastic elastomers (TPE), thermoset elastomers, and fluoro-elastomers, elastomeric copolymers, elastomeric terpolymers, elastomeric polymer blends and a variety of elastomeric alloys. The particular type of elastomeric material utilized depends in part on the application A variety of commercially available elastomeric materials are useful with the subject invention. For example, butyl elastomer sold under the trade names of EXXON Butyl (Exxon Chemicals) or POLYSAR (Bayer Corp) performs well for MEK, silcone fluids and greases, hydraulic fluids, strong acids, salt, alkali and chlorine solutions. Ethylene and propylene are often substituted for butyl. Chloroprene sold under the trade names of BAYPREN (Bayer Corp) and NEOPRENE (DuPont Dow) performs well in petroleum oils with a high aniline point, mild acids, refrigeration seals (having resistance to ammonia and Freon), silicate ester lubricants and water. Chloroprene is also known as polychloroprene having a molecular structure similar to natural rubber. Similarly, chlorosulfonated polyethylene sold as HYPALON (DuPont Dow) performs well with acids, alkalis, refrigeration seals (resistant to Freon), diesel and kerosene. Chlorosulfonated polyethylene has good resilience and is resistant to heat, oil, oxygen and ozone. Epichlorihydrin sold under the trade name of HYDRIN (Zeon Chemicals) performs well in air conditioners and fuel systems. Epichlorihydrin is oil resistant and often used in place of chloroprene where low temperatures are a factor, having better low temperature stiffness. Ethylene Acrylic sold under the trade name of VAMAC (DuPont Dow) performs well in alkalis, dilute acids, glycols and water. This rubber is a copolymer of ethylene and methyl acrylate and has a low gas permeability and moderate oil swell resistance. Also, ethylene acrylic has good tear, abrasion and compression set properties. Ethylene propylene sold under the trade names of BUNA EP (Bayer Corp), KELTAN (DSM Copolymer), NORDEL (DuPont Dow), ROYALENE (Uniroyal) and VISTALON (Exxon Chemical) resists phosphate ester oils (Pydraul and Fyrquel), alcohols, automotive brake fluids, strong acids, strong alkalis, ketones (MEK, acetone), silicone oils and greases, steam, water and chlorine solutions. EPDM is, for example, a terpolymer made with ethylene, propylene, and diene monomer. Fluoro-elastomers sold under the names of DAI-EL (Daiken Ind.), Dyneon (Dyneon), Tecnoflon (Ausimont) and VITON (DuPont Dow) perform well in acids, gasoline, hard vacuum service, petroleum products, silicone fluids, greases and solvents. Fluoroelastomers have a good compression set, low gas permeability, excellent resistant to chemical and oils. Having high fluorine to hydrogen ratio, these types of compounds have extreme stability and are less likely to be broken down by chemical attack. Fluorosilicone sold under the trade names of FE (Shinco Silicones), FSE (General Electric) and Silastic LS (Dow Corning) performs well as static seals due to high friction, limited strength and poor abrasion resistance and particularly with brake fluids, hydrazine and ketones. Hydrogenated Nitrile sold under the trade names of THERBAN (Bayer Corp.) and ZETPOL (Zeon Chemicals) performs well in hydrogen sulfide, amines (ammonia derivatives), and alkalis, and under high pressure. Hydrogenated Nitrile is often used as a substitute for FKM materials and has high tensile properties, low compression set, good low temperature properties and is heat resistant. Natural rubber performs well in alcohols and organic acids and has high tensile strength, resilience, abrasion resistance and low temperature flexibility in addition to having a low compression set. Nitrile sold under the trade names of KRYNAC (Polysar Intl), NIPOLE (Zeon Chemicals), NYSYN (Copolymer Rubber and Chemicals) and PARACRIL (Uniroyal) performs well in dilute acids, ethylene glycol, amines petroleum oils and fuels, silicone oils, greases and water below 212° F. Also known as Buna-N, nitrile is a copolymer of butadiene and acrylonitrile. Perfluoroelastomer sold under the trade name AEGIS (International Seal Co.), CHEMRAZ (Greene Tweed), KALREZ (DuPont Dow) has low gas permeability and is resistant to a large number of chemicals including fuels, ketones, esters, alkalines, alcohols, aldehydes and organic and inorganic acids and exhibits outstanding steam resistance. Polyurethane sold under the trade names of ADIPRENE (Uniroyal), ESTAE (B. F. Goodrich), MILLITHANE (TSE Ind.), MORTHANE (Morton International), PELLETHANE (Dow Chemical), TEXIN (Bayer Corp.) and VIBRATHANE (Uniroyal) performs well under pressure, is very tough and has excellent extrusion and abrasion resistance. Silicone sold under the trade names of BAYSILONE (Bayer Corp.), KE (Shinco Silicones), SILASTIC (Dow Corning), SILPLUS (General Electric) and TUFEL (General Electric) performs well in oxygen, ozone, chlorinated biphenyls and under UV light. Silicones have great flexibility and low compression set. Tetrafluoroethylene (“TFE”) sold as ALGOFLON (Ausimont) and TEFLON (DuPont Dow) performs well in ozone and solvents including MEK, acetone and xylene. Tetrafluroethylene/propylene is a copolymer of TFE and propylene sold under the trade names of AFLAS (Asahi Glass), and DYNEON BRF (Dyneon). Tetrafluroethylene/propylene performs well in most acids and alkalis, amines, brake fluids, petroleum fluids, phosphate esters and steam.
[0052] As shown in the examples below, VITON®, a material developed by DuPont that is in the family of fluoro-elastomers is utilized as an elastomeric material. Chemically it is known as a fluorinated hydrocarbon. VITON® comes in several grades A, B, and F in addition to high performance grades of GB, GBL, GP, GLT, and GFLT.
[0053] Some of the physical properties of VITON® are as follows:
Durometer Range on the Shore scale 60-90 Tensile Range 500-2000 psi Elongation (Max %) 300 Compression set GOOD Solvent Resistance EXCELLENT Tear Resistance GOOD Abrasion Resistance GOOD Resilience-Rebound FAIR Oil Resistance EXCELLENT Low Temp range −10 F. High Temp Range 400-600 F. Aging-weather and sunlight EXCELLENT
[0054] VITON® provides chemical resistance to a wide range of oils, solvents, aliphatic, aromatic, and halogenated hydrocarbons, as well as to acids, animal and vegetable oils.
[0055] As also discussed in the examples, urethane is a thermoset elastomer as previously discussed. Some of the relevant properties of urethane are as follows:
Durometer Range on the Shore scale 68A-80D Tensile Range 2100-9000 psi Elongation 150-885 Compression set 15-45% Modulus 100% 330-7800 Modulus 300% 470-8400 Tear Strength Die C. pli 205-1380 Tear Strength Split, pli 55-476 Bayshore Rebound 18-58% Cured Density 1.07-1.24
[0056] Generally, thermoplastic elastomers (TPE) as defined in the Modern Plastics Encyclopedia (1997, 1998) are “soft flexible materials that provide the performance characteristics of thermoset rubber, while offering the processing benefits of traditional thermoplastic materials”. Hence, the thermoplastic material, a typically rigid material, is modified at the molecular level to become flexible after molding. TPE materials are popular because they are easy to make and mold.
[0057] The mechanical and physical properties of TPE's are directly related to the bond strength between molecular chains as well as to the length of the chain itself. Plastic properties can be modified by alloying and blending in various substances and reinforcements. The ease at which TPE's can be modified is a distinct advantage of these materials. The mechanical properties of these materials can be customized to suit a particular application or service.
[0058] Thermoset elastomers are plastic substances that undergo a chemical change during manufacture to become permanently insoluble and infusible. Thermoset polymers are a subset of thermoset elastomer material as these materials undergo vulcanization enabling them to attain their properties. The key difference between a thermoset elastomer and a thermoplastic elastomer is the cross-linking of the molecular chains of molecules that make up the material. Thermoset materials are cross-linked and TPE materials are not.
[0059] The family of preferred fluoro-elastomers may be subdivided into seven categories:
[0060] 1) copolymers meaning combinations or blends of two polymers;
[0061] 2) terpolymers meaning combinations or blends of three polymers. These typically have good heat resistance, excellent sealing and good chemical resistance;
[0062] 3) low temperature polymers, which have good chemical resistance and excellent low temperature properties;
[0063] 4) base resistant polymers, which have superior chemical resistance to bases, aggressive oils and amines;
[0064] 5) peroxide cure polymers, which have superior chemical resistance and excellent sealing properties;
[0065] 6) specialty polymers; and
[0066] 7) perfluorinated polymers, which have superior chemical resistance and excellent sealing properties.
[0067] Copolymers are materials made up of two or more different kinds of molecule chains. They are basically a combination of different materials fused into one. The individual compounds that make up the molecular chain are distinct and repeating over the length of the molecular chain. A terpolymer is a copolymer with three different kinds of repeating units. A homopolymer identifies a polymer with a single type of repeating unit. Other repeating units are possible as well. Alloys are elastomers with additives that improve the properties of the material, much like metal alloys.
[0068] Well known to those skilled in the art, the utility of rubber and synthetic elastomers is increased by compounding the raw material with other ingredients in order to realize the desired properties in the finished product. For example vulcanization increases the temperature range within which elastomers are elastic. In this process, the elastomer is made to combine with sulphur, sulphur bearing organic compounds or with other chemical crosslinking agents. Any number of ingredients can be combined in any number of ways to generate any number of mechanical or chemical properties in the finished elastomeric material.
[0069] In general, the elastomeric materials useful in the subject invention operate within the following ranges:
[0070] TEMPERATURE=−120° F. to 450° F.
[0071] PRESSURE=vacuum to 12,000 psi
[0072] DIFFERENTIAL PRESSURE=0 to 10,000 psi
[0073] SERVICE TYPE=Continuous or intermittent duty in any type of compressible gas or gas mixture.
[0074] OPERATING EQUIPMENT=Reciprocating gas compressors in any industry from any manufacturer of reciprocating gas compressors.
[0075] These ranges are typical for reciprocating gas compressors. Other elastomers can operate in more extreme temperatures and pressures depending on the characteristics of the elastomeric material used.
[0076] Other important characteristics of the elastomers are:
[0077] durometer range on the Shore scale or analogous scale, which is a measure of the hardness of the elastic material.
[0078] tensile strength, which is the approximate force required to make a standard material sample fail under a tensile load.
[0079] elongation, which is the amount of deformation that a sample will exhibit before failure. An elongation of 200% indicates that the sample will stretch 2 times its original length before failure.
[0080] compression set, which is a measure of the elastic materials ability to withstand deformation under constant compression.
[0081] solvent resistance, which indicates a compound's resistance to solvents that normally dissolve or degrade elastomers in general.
[0082] tear resistance, which is the ability of the elastic material to withstand tearing and shear forces.
[0083] abrasion resistance, which is the ability of the elastic material to withstand abrasion and rubbing against another material or itself.
[0084] rebound resilience, which is the measure of the ability of an elastic material to return to its original size and shape after compression.
[0085] oil-resistance, which is the relative ability of an elastic material's resistance to penetration or degradation by various hydraulic or lubrication oils commonly used in industrial services. Many reciprocating gas compressors have lubricated compressor cylinders.
[0086] aging, weather, and sunlight resistance, which is the ability of the elastic material to withstand the elements. This is not a factor in this particular use because the elastic materials will be inside of machine components.
[0087] Hence, the specific elastomeric material used for the elastomeric layer will be dictated by requirements of the reciprocating gas compressor and the compressor valves. In a chemical rich environment, an elastomer, such as a peroxide-cured polymer, having superior chemical resistance properties is required. Similarly, unusual temperature environments mandate certain appropriate properties. Engineers and individuals experienced with gas compression may analyze a particular set of operating parameters and select a material with the appropriate properties. For this reason, there will necessarily be a large number of potential elastomer compounds that may be selected or custom designed to perform in a particular set of operating conditions. The blending and the ability to modify the mechanical and chemical properties of elastomers and/or thermoplastics offer an extensive array of possible solutions to any gas compression application. This key advantage of elastomers will yield high performance solutions to common or difficult applications where none existed previous to this invention.
[0088] Examples of reciprocating gas compressor valves useful in the practice of the subject invention include U.S. Pat. No. 3,536,094 to Manley (also known as the MANLEY® valve), and U.S. Pat. No. 5,511,583 to Bassett. The teachings and disclosures of these patents are incorporated herein by reference as if fully set out herein. The MANLEY® valve is a concentric ring type of valve constructed of non-metallic thermoplastic resin. In this type of valve, the sealing element thickness may vary by design with rounded or straight vertical edges. The MANLEY® valve has a downwardly convex protruding sealing element to engage a recessed seating surface in the valve seat. U.S. Pat. No. 5,511,583, Bassett discloses the MOPPET® valve, a single element non concentric valve. When open fluid flows over the inner and outer annuls of the sealing element. The MOPPET® sealing element is different than the poppet valve sealing element (FIG. 6). In the MOPPET® valve, fluid flow travels through both an inner annulus and an outer annulus of the sealing element. In a poppet valve, fluid flows over the outer annulus of the sealing element only because it does not have a center hole.
[0089] The sealing element of the subject invention may be of various forms and types when utilized in reciprocating gas compressor valves. Generally, as depicted in the Figures, a reciprocating gas compressor valve comprises a sealing element 10 and a seating surface 12 having an opening 20 for intake and exhaust of gas. The seating surface 12 surrounds the periphery of the opening 20 . The sealing element 10 is sized and shaped to correspond with, and fully close the opening 20 when engaged against the seating surface 12 . The seating surface 12 may be part of a sealing element 10 . For example, the elastomeric material may be applied under the appropriate circumstances to the seating surface 12 either in combination with the sealing element 10 or alone.
[0090] The intake or exhaust gas flows into or out of the reciprocating gas compressor through the opening 20 . Operation of the reciprocating gas compressor requires that the opening 20 of the reciprocating gas compressor valve be alternately opened and closed. The opening 20 is closed when the sealing element 10 is moved into contact with the seating surface 12 and closes the opening 20 . When the sealing element 10 is moved out of contact with the seating surface 12 , the opening 20 is opened and gas is permitted to flow into or out of the reciprocating gas compressor cylinder depending on whether the valve is located in the suction or discharge position of the reciprocating gas compressor cylinder.
[0091] The opening 20 and sealing element 10 are often cylindrical or spherical; however, the opening 20 and sealing element 10 of reciprocating gas compressor valve may be of any geometric configuration. The only requirement is that the size and shape of the sealing element 10 must correspond to the opening 20 in order to effectuate a seal.
[0092] The movement of a sealing element 10 is often limited by a guard (also referred to as a “stop plate”). Typically, the reciprocating gas compressor geometry is such that when the seat plate 10 and the guard are joined together, there is space available between the two for the sealing element 10 to move away from the seating surface 12 and against the guard. In modern reciprocating gas compressor designs it is possible to control the total travel of the sealing element 10 by adjusting the geometry of the guard and/or varying the thickness of the sealing element 10 . The distance traveled by the sealing element is generally decided by the manufacturer of the reciprocating gas compressor valve after analysis of the operating conditions. While the distance is generally not a concern, there is a historical pattern suggesting that valves with sealing elements with high travel distances have a lower time between failures than valves with low travel distances. This is likely because the greater travel distance permits more time for the sealing elements to accelerate and thereby increasing the impact velocities described previously.
[0093] In almost all current compressor valve designs a mechanism is in place (usually a spring) that is placed in the guard for the purpose of pushing the sealing element 10 toward the seating surface 12 . In other words, the spring or some other device will push the sealing element 10 against the seating surface 12 , resulting is a gas tight seal when the compressor valve is in a static, non-pressurized condition. During operation the purpose of the spring 14 or other mechanism is to push the sealing element 10 toward the seating surface 12 at some point in time before the compressor piston reaches top or bottom dead center. By varying the spring forces, the valve designer can influence the velocity of valve sealing elements and thereby control (to some extent) the impact forces between the seat and sealing element.
[0094] Top or bottom dead center refers to the position of the compressor piston within the compressor cylinder. Since reciprocating gas compressor cylinders may be double acting, the reference to top or bottom dead center is relevant only after it is determined which end of the compressor cylinder is being analyzed. When the piston reaches top or bottom dead center at the conclusion of the discharge or suction stroke, the piston changes direction, and pressures inside the compressor cylinder reverse. Pressure that was increasing starts to decrease (and vice versa) as soon as the piston reverses direction. If this occurs and the valve sealing element(s) is some distance away from the sealing surface the valve sealing element(s) can be forced against the seat plate in a violent manner by the changing gas pressure. Differential pressure forces can be substantial. A spring or other suitable mechanism is installed behind the sealing element 10 to push the sealing element 10 toward the seating surface 12 well before top or bottom dead center such that the pressure changes resulting from the change in direction of the compressor piston do not accelerate the valve sealing elements to excessive or destructive speeds.
[0095] Technology and trends in reciprocating gas compressor philosophy have resulted in smaller reciprocating gas compressors being operated at higher speeds. Typically reciprocating gas compressors in industrial process services were operated at piston speeds no higher than about 800 ft/min. Piston speed is a function of crankshaft speed, and compressor stroke. Piston speeds have been set by convention (see API-618) as a means for increasing the mean time between failures of not only the compressor valves but other compressor components. Recently these slow speed philosophies have been abandoned for high speed, short stroke reciprocating gas compressors. As speed increases, there is necessarily less time for a compressor cylinder to expel compressed gas or admit new gas before the piston reaches top dead center. This effectively reduces the time available for the compressor valve elements to travel their full allowable distance. The increase in speed has resulted in an increase in the impact forces between the seating surface 12 and the sealing element 10 , which results in a decrease in the mean time between failures of the valve seating surface 12 or sealing element 10 . In addition, faster rotating speeds result in a considerable increase in the number of opening and closing events over a given time period. This results in a decreased useful life of the compressor valve and possibly also the reciprocating gas compressor.
[0096] The novel use of elastomeric compounds as the sealing element in valves is applicable for use in reciprocating gas compressors that are driven by electric motors, gas or liquid fuel engines, steam turbines or any other energy conversion device that provides power to a shaft for the purposes of imparting a rotating motion to a crankshaft. The reciprocating gas compressor may be directly coupled or indirectly coupled to the driver through the use of gears, belts, etc.
[0097] All reciprocating gas compressors are fundamentally the same. They are built with one or more compressor cylinders attached to a common crankshaft for the purpose of raising the gas from one pressure to another higher pressure. The reciprocating gas compressors may operate as a single stage unit or they can be designed for multistage operation. The gas cylinders can be oriented in any direction in relation to the crankshaft or to each other. Reciprocating gas compressors may be designed to operate in series or parallel with other compressors.
[0098] There are many manufacturers of reciprocating gas compressors. Each gas reciprocating gas compressor, however, performs the same task but varies in form and size. Currently known manufacturers of reciprocating gas compressors include: ABC Compressor; Ajax (Cooper); Aldrich Pump; Alley; Ariel; Atelier Francois; Atlas Copco; Bellis & Morcam; Blackmer Pump; Borsig; Broomwade; Bryn Donkin; Burckhardt; Burton Corbin; C. P. T.; Chicago Pneumatic; Clark; Consolidated Pneumatic; Corken; Crepelle; Creusot Loire; Delaval; Demag; Du Jardin; Ehrardt & Schmer; Einhetsverdichter; Energy Industries; Essington; Framatome; Frick Bardieri; Gardner Denver; Halberg; Halberstadt; Hitachi; Hofer; IMW; Ingersoll Rand; Ishikawajima-Harima Heavy Industries (IHI); Iwata Tosohki; Japan Steel Works; Joy; Kaji Iron Works; Khogla; Knight; Knox Western; Kobe Steel; Kohler & Horter; Mannesmann Meer; Mehrer; Mikuni Heavy Industries; Mitsubishi Dresser; Mitsui; Neuman & Esser; Norwalk; Nuovo Pignone; Pennsylvania Process Compressor (Cooper); Pentru; Penza; Peter Brotherhood (FAUR); Quincy; Reavell; Sepco; Siad; Suction Gas Engine Company; Sulzer; Superior (Cooper); Tanabe; Tanaise; Thomassen; Thompson; Undzawa Gumi Iron Works; Vilter; Weatherford Enterra (Gemini); Whitteman; and Worthington. FIGS. 7 a and 7 b shows a typical arrangement and design of a reciprocating gas compressor. Generally, each reciprocating gas compressor has a driver 16 , a frame 18 , a throw 22 , at least one compressor cylinder with a crank end 24 and a head end 26 , suction valves 28 and discharge valves 30 , or valves that are combination suction and discharge valves (not shown).
EXAMPLE 1
[0099] As a first field test, a 1400 rpm Ariel reciprocating gas compressor was used in gas gathering service. This machine is desirable for testing the sealing element of the subject invention because of its rotating speed. A large number of opening and closing cycles may be accumulated in a short period of time. In this initial test, 90 durometer fluoro-elastomer, Mosites was applied to a nylon disk and used in a MOPPET® valve. The materials ran for six (6) days before failure occurred. Inspection of the parts indicated that the nylon base material melted and subsequent deformation of the parts and loss of seal, resulted in overheating and forced a shutdown of the compressor.
[0100] Nylon is no longer being used as a base material. PEEK has been applied as a result of its ability to operate at higher temperatures. The same elastomeric material, Mosites, was applied to the PEEK disks and the parts were run again. The parts ran for about 205 days before failure occurred. The standard product (PEEK) without a layer of elastomeric material operated for eight (8) months. The parts were, for the most part, destroyed. However, two sealing elements were intact and showed minimal wear. As shown in FIGS. 4 and 5, the line of contact made by the sealing element with the seating surface may create a local high stresses in the elastomer. The sealing element suffered higher contact loads, resulting from the line contact. It was resolved to change to a surface type of contact. Notwithstanding, the sealing element was soft and flexible and the bond between the elastomeric material and the PEEK held up well. In this Example, the reciprocating gas compressor specifications were as follows:
Suction Pressure = 300 psi Discharge Pressure = 540 psi Suction Temperatures = 80° F. Discharge Temperatures = 200° F. Sealing Element Travel = 0.160 inches RPM = 1350 Compressor: Ariel IGE Gas: Wellhead Gas (mixture of mostly methane and other hydrocarbons)
EXAMPLE 2
[0101] In the first test of the urethane material, the material failed in four (4) days and inspection revealed that the bond between the urethane and the PEEK material permitted the urethane to separate from the PEEK at discharge temperatures. In addition, the PEEK used in this test had been colored black by the addition of carbon which has the detrimental effect of making the thermoplastic material slippery. The MOPPET® valve parts were essentially undamaged but it was clear the bonding chemical between the urethane and the plastic allowed the urethane to separate. The suction valves were intact and in good condition because the suction temperatures are much lower than discharge temperatures. It seemed clear that the bonding agent had temperature limitations. Other bonding agents capable of withstanding higher temperatures must be utilized.
[0102] It should be noted that the standard valve (without the use of elastomeric material) began to overheat in only a few hours before having to be removed. While the urethane failed prematurely, it should be noted that while the valve parts were intact the temperatures were normal and operation was improved with the elastomers. Compressor specifications were:
Suction Pressure = 43.5 psi Discharge Pressure = 174 psi Suction Temperatures = 27° F. Discharge Temperatures = 212° F. Sealing Element Travel = RPM = 1188 0.120 inches Gas: 81% Methane Compressor: Ariel JGH-4 6.9% Ethane 4.6% Propane
EXAMPLE 3
[0103] In this example, the reciprocating gas compressor operated at a rather low compression ratio and the temperatures were low and the urethane sealing element applied to standard (non-black) PEEK ran continuously for over 100 days without problems. This provided the evidence that bonding materials are temperature sensitive. Adhesives and primers able to withstand higher temperatures and new radiused valve seats (surface vs. line contact) were installed. Compressor specifications were as follows:
Suction Pressure = 503 psi Discharge Pressure = 783 psi Suction Temperatures = 106° F. Discharge Temperatures = 169° F. Sealing Element Travel = RPM = 327 0.120 inches Gas: 75.5% Hydrogen Compressor: Cooper JM-3 19.5% Methane 3.1% Ethane
EXAMPLE 4
[0104] The elastomers materials are tested in two different services as follows:
[0105] 1. Flare gas service: This service is characterized by low pressures and dirty gas. Essentially flare gas is made up of all of the gas that leaks from all of the other machines in the plant. Flare gas is a particularly difficult service for compressor valves because the molecular weight and corrosive properties of the gas change frequently over time. This gas is compressed and sent to the flare for disposal. Because of the low pressure, 70 durometer fluoro-elastomer is used. The lower hardness will permit the test pieces to seal more readily at operating pressures. The standard non-black PEEK is being used.
[0106] 2. Hydrogen service: This service is characterized by high pressures but rather clean gas. Pressures go to 3200 psi with differential pressures approaching 1500 psi. Standard non-black PEEK is being used with a very hard (>90 durometer) compound. The high pressure of this service will put rather high loads on the elastomers and a stiffer compound is required.
[0107] Compressor specifications were as follows:
Flare Gas Suction Pressure = 0.29 psi Discharge Pressure = 26.8 psi Suction Temperatures = 150° F. Discharge Temperatures = 293° F. Sealing Element Travel = RPM = 392 0.100 inches Gas: 60% Hydrogen (Flare Gas) Compressor: IR HHE-VE-3 6% to 17% Methane 1% to 5% Ethane Hydrogen Service Suction Pressure = 1263 psi Discharge Pressure = 1825 psi Suction Temperatures = 112° F. Discharge Temperatures = 177° F. Sealing Element Travel = RPM = 327 0.100 inches Gas: 79% Hydrogen (Hydrogen Compressor: Clark CLBA-4 Service) 14% Methane 3.6% Hydrogen Sulfide
EXAMPLE 5
[0108] This service is high pressure hydrogen similar to Example 4. Test pieces were made from standard PEEK with the extra hard fluoro-elastomer material, 80-90 durometer mosites 10290 compound.
[0109] Compressor Specifications are as follows:
Suction Pressure = 1662 psi Discharge Pressure = 3130 psi Suction Temperatures = 120° F. Discharge Temperatures = 233° F. Sealing Element Travel = RPM = 300 0.080 inches Gas: 92% Hydrogen Compressor: Worthington BDC-4 6.4% Methane
EXAMPLE 6
[0110] This application is somewhat different than the others because for the first time the elastomeric material is applied to a ported plate geometry as shown in FIG. 1. Two valve designs notorious for being unreliable are used. Due to the size of the valves, a new valve design was developed that made use of the elastomer. Test pieces were made using standard, non-black PEEK. The mold requires adjustment until the parts are uniform.
[0111] In the above examples (field tests), the reciprocating gas compressors were subjected to typical and routine compressor inspections. In both cases, a standard valve using current thermoplastic materials located on an adjacent compressor cylinder was monitored and compared to a cylinder with the new elastomeric materials. The accelerometer traces showed that at both locations, the elastomeric materials lowered the impact energies by approximately two thirds. While the use of elastomers would lead one to expect lower impact energies, the magnitude of the improvement was dramatic and surprising. The reduction of impact energies by the use of elastomers has been verified twice in two separate service conditions and locations.
[0112] The elastomeric sealing element made an improvement to the overall reciprocating gas compressor performance. The elastomeric sealing element has less mass than the solid Nylon or PEEK versions and one of the inherent properties of elastomers is that they absorb shock and impact better than other materials. In the field, reciprocating gas compressors can be analyzed during operation and a number of useful parameters can be recorded. With ultrasonic equipment and accelerometers (in addition to pressure and temperature measurements), it is possible to form a rather complete picture of actual reciprocating gas compressor performance.
[0113] Ultrasonic equipment can “hear” gas leaking passed the sealing elements in a valve and the accelerometers can detect the magnitude of the impact of the valve elements as they move from full open to full closed. Detecting leaks and the observation of high impact energies permits one to make predictive decisions about the condition of the reciprocating gas compressor and assist in scheduling a maintenance turnaround before catastrophic failures occur.
[0114] Since it is unlikely that any one elastomeric material will serve all applications, additional test sealing elements were made using, ethylene/acrylic, styrene/butadiene, hydrogenated nitrile, neoprene, silicone/ethylene propylene, isobutylene/isoprene, natural rubber, tetrafluoroethylene/propylene, carboxylated nitrile, chlorinated polyethylene and ethylene propylene diene monomer (EPDM) elastomers. These parts were made to: (1) prove that they could be attached to the other materials, and (2) to await testing in services where the strengths of the elastomic material can be tested and evaluated.
[0115] All of the elastomers were subjected to static pressure testing for the purposes of evaluating their tendency to extrude into the slots (flow areas) of the valve seat. Each of the materials performed well and it should be noted that the hardness of these materials is somewhat less than the 80-90 durometer of the compounds in current field tests. Any small change made in the compounding of these materials will stiffen or soften the material to any desired hardness.
[0116] The relevant properties of these and other elastomeric materials are shown in FIGS. 8 and 9. As shown in these figures, use of elastomeric material on the reciprocating gas compressor valve, the impact energies are reduced. FIG. 8 represents data from one of the tests prepared for a single elastomeric sealing element made entirely of elastomer, Mosites 10290 material (fluoroelastomer similar to VITON®) and 58D urethane material produced by Precision Urethane. The elastomeric material was molded into the shape of a MOPPET® sealing element.
[0117] The significance of FIG. 8 is that it shows the deflection of the sealing element when subjected to a pressure load. It helps one skilled in the art to determine whether the hardness of material is appropriate for the service. Two samples predictably compress as pressure increases but at about 800 to 900 psid the parts were pushed beyond the sealing surface and into the orifices of the seat itself. Remarkably, upon inspection after the test, the elastomeric material had not ruptured and was recovered in nearly its original shape. The test also revealed that sealing elements comprised completely of elastomeric material would only be effective up to about 600 to 700 psid in actual service conditions, representing only a small part of the total operating envelope that can be addressed with a reciprocating gas compressor. To cover the full spectrum of the desired operating envelope, sealing elements must handle substantially higher pressure differentials. Current production PEEK sealing elements used in MOPPET® valves have been subjected to static differential pressures in excess of 5000 psid with little or no significant deflection.
[0118] [0118]FIG. 9 shows the deflection versus pressure curves for sealing elements built with an elastomeric material bonded to a nylon or PEEK substrate. At the time of this test, no differentiation was made between the use of PEEK or nylon but subsequent field testing would essentially rule out nylon for use as a candidate for this idea. FIG. 9 has six (6) curves labeled according to the thickness of the elastomer (58D urethane in this case) and the resultant deflection under load. It is clear from the curves that the concept of applying elastomer to a rigid substrate material was the key to surviving high differential pressures. A thick layer of elastomeric material is likely to perform better at lower differential pressures than a thin layer and the test data evidences this.
[0119] For most applications, a MOPPET® sealing elements having a 0.100 to 0.050 inches thick layer of elastomeric material covers the widest range of differential pressures. Based on this data and similar curves for the Mosites 10290 material, it was determined that elastomer thickness could be limited to 0.100 or 0.050 inches. Minimizing the number of product variations helps control production costs and makes application of the product easier by limiting the number of available options. This method of testing is useful to measure the potential of other materials that may be suitable for use in compressor valves and aid those skilled in the art to make competent material selections.
[0120] In addition to the elastomer layered valves described above, it is believed that other elastomer materials will perform equally in terms of performance since the premise of this idea is to make use of the inherent properties of elastomers. It should be noted that the elastomers herein described have a hardness that is somewhat less than 90 durometer (approximately 70D). However, should a hardness greater than 90 durometers be desired, one can simply make small changes in the compounding of these elastomers to stiffen them to any desired hardness to obtain the desired sealing performance.
[0121] In order to determine which elastomer compound can be used for a particular application, static pressure testing can be performed on each elastomer compound or elastomer mixture compound to determine the amount of deflection the elastomeric compound will undergo at certain differential pressure intervals. From this data, the propensity of an elastomeric layered part to extrude into a seat can be determined. One skilled in the art can match the pressure conditions, the results of the static pressure test and historical data to determine the proper elastomeric material to use for the particular application. In addition, consideration of the operating temperatures and the corrosive properties of the gas will influence the material(s) used.
[0122] For example, a flare gas service is characterized by low pressure and dirty gas which can vary greatly in composition. Because of the low pressures, a less stiff elastomer compound, such as a 70 durometer fluoro-elastomer, can be used. In comparison, hydrogen service is characterized by high pressure and clean gas with little or no variation in gas composition. Pressures can reach as high as 3200 psi with differential pressures approaching 1500 psi (typical but can go higher). Therefore, a much harder elastomeric material (greater than 90 durometer) seems to be appropriate. An engineer skilled in the art can use the static pressure test results to match the proper compound with each particular service to obtain optimum reciprocating gas compressor performance.
[0123] Common engineering elements such as pumps, gauges, controllers, computers, software and the like are not shown or described except when necessary for the understanding of the invention, since for the most part selection and placement of such equipment is well within the skill of the ordinary engineer. Although the above apparatus and process are described in terms of the above embodiments, those skilled in the art will recognize that changes in the apparatus and process may be made without departing from the spirit of the invention. Such changes are intended to fall within the scope of the following claims.
[0124] Detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale where some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention.
[0125] Although making and using various embodiments of the present invention have been described in detail above, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention, and do not delimit the scope of the invention. | This invention relates to the use of elastomers with the sealing element of reciprocating gas compressor valves to increase the reliability of the gas tight seal within the reciprocating gas compressor valve and to increase the useful life of reciprocating gas compressor valve. The elastomeric material is either used as a coating layer on the sealing element of the reciprocating gas compressor valve, or as the entire sealing element. The elastomeric material acts as a cushion to reduce the wear on the sealing element, provides a superior gas tight seal, and is more tolerant of entrained dirt or liquids in the gas stream thereby increasing the operable life of the reciprocating gas compressor valve. Reducing the mean time between reciprocating gas compressor valve failures results in longer reciprocating gas compressor run times for the user, increased revenue generation for the user and safer operation of said equipment. | 5 |
[0001] This application is a continuation of U.S. application Ser. No. 10/805,883, filed Mar. 22, 2004, which claims the benefit of U.S. Provisional patent application Ser. No. 60/459,105, filed Mar. 31, 2003, the entire disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a pest control system which includes a pest control active ingredient and isodiphenyl phosphate as an agent to reduce parasthesia of the active ingredient. The system releases the active ingredient efficiently and uniformly. The pest control system is less irritating to the animal's skin as compared to prior art systems. The system is useful for making animal collars, ear tags, pest strips, liquid spot-on treatments, and the like.
BACKGROUND OF THE INVENTION
[0003] Many pest control active ingredients cause irritation (parasthesia) to warm blooded animals (including humans). This irritation to the skin and/or eyes of warm blooded animals hampers the use of pest control active ingredients. This irritation factor occurs even when the pest control active ingredient is blended with polymers or in other formulations (such as granules, dusts, dips, liquids, emulsions, etc.) wherein the active ingredient is considerably diluted.
[0004] U.S. Pat. No. 5,437,869 describes the use of triphenyl phosphate, a solid at room temperature, to reduce these phenomena. The more irritating the active, the higher the ratio of TPP is required. These ratios of TPP to active may be incorporated into a solid. However, when a liquid pest control system is required, a problem arises when a high level of active ingredient is also required. Due to the solubility characteristics of TPP, a high percentage of highly irritating active does not leave room for a high ratio of TPP and remain in liquid form at room temperature. Even a one-to-one ratio cannot be achieved in a liquid product and remain stable when a high level of active ingredient is required. For example, 50% active ingredient +50% TPP becomes a solid at room temperature. Additionally, in some applications it is desired to utilize a high level, up to sixty percent or more, of active ingredient and remain as a liquid in order to minimize the dose amount used in a single application. An animal spot-on product is an example of a need for a small dose amount of formulation measured in drops, which necessitates a high concentration of active agent in the formulation in order to obtain acceptable pest control.
SUMMARY OF THE INVENTION
[0005] The present invention is directed to a method and a composition for the controlled delivery of a pest control active agent or a mixture of active agents while reducing the irritation of the pest control active agent to warm blooded animals. More particularly, the pest control system of the invention comprises a pest control formulation comprising a pest control active agent and isodiphenyl phosphate (isodecyl diphenyl phosphate, IDPP) as a parasthesia-reducing agent for the active agent. The formulation may optionally include other ingredients as necessary or desired, depending on the particular active agent chosen and the form of the final product. Such optional ingredients can include, but are not limited to, system carriers such as polymers, clays, water, solvents, and the like; plasticizers; synergists; fragrances; coloring agents; preservatives; antioxidants; light stabilizers; and the like. The resulting pest control system may take the form of a solid, such as a polymer, granule, powder or dust; a liquid, such as a dip, a spray, or a spot-on; or an emulsion; as long as the pest control active agent and the IDPP remains associated together as a group within the pest control system, such that the combination is maintained when released to the locus of treatment.
[0006] The present invention is further directed to a method for reducing the irritation to warm blooded animals of a liquid pest control active agent in a solid or liquid, preferably liquid, pest control system, the method comprising associating IDPP together with the active agent into the pest control formulation, the amount of IDPP present being an amount effective to reduce the irritation of the active agent to warm blooded animals.
[0007] The system of the invention provides a non-paresthesia producing stable formulation that may include a high percentage of the irritating active agent. This invention further allows for a high concentration of active agent, such as pyrethrins and synthetic pyrethroids, in a stable liquid formulation, while reducing any irritation of the active agent. The system of the invention is effective without loss of the biological activity of the active agent. This invention is particularly useful for reducing the irritation of synthetic pyrethroids to warm blooded animals. This invention is further particularly useful when the pest control system is a liquid.
DETAILED DESCRIPTION OF THE INVENTION
[0008] As used herein, “a” and “an” mean one or more, unless otherwise indicated. “Parasthesia” as used herein and in the appended claims is defined as primarily a condition that results in a feeling (burning, tingling, and/or pricking sensation) of the skin.
[0009] Isodiphenyl phosphate (isodecyl diphenyl phosphate, CAS #29761-21-5; IDPP) is a liquid, is insoluble in water, has a low vapor pressure and is also heavier than water, which allows a formulation to become water-resistant after the water (if any) has evaporated. It is compatible with high concentrations (that is, of up to about 30 wt%, preferably up to about 40 wt%, more preferably up to about 50 wt% or more) of liquid active agents, including synthetic pyrethroids.
[0010] The pest control active agent may be chosen from any active agent known to be useful in the control of insect or acarid pests, such as but not limited to a natural or synthetic pyrethroid, a carbamate, a phosphate, a phosphorothioate, etc. The present invention is particularly useful for delivering pest control active agents that cause paresthesia in warm blooded animals, although the invention is not limited thereto. Synthetic pyrethroids are well-known to be irritating to animals. Thus, in a presently preferred embodiment of the present invention, the pest control active agents are selected from pyrethroids. However, any active agent that causes paresthesia in animals is included within the present invention. The active agents may be liquids or solids at room temperature. While the invention is particularly useful for delivering liquid active agents at high concentrations in the formulation, the invention is not limited thereto but may also be used with active agents, either liquid or solid, at any concentration. One or more active agents may be included within the formulation of the present invention. Exemplary pesticides and repellents which are effective against horn flies, face flies, stable flies, house flies, mosquitoes, lice, ticks, and mites are carbaryl, propoxur, dichlorvos, naled, diazinon, pyrethrin, cypermethrin, decamethrin, cyhalothrin, flumethrin, cyfluthrin, fenvalerate, deltamethrin, fempropathrin, fluvalinate, flucythrinate, cyfluthrin, alphamethrin, tralomethrin, cycloprothrin, karate, gokilaht, or any synthetic pyrethroid with a cyano group in it's molecular structure. Preferred pest control active agents are the pyrethrins and synthetic pyrethroids, more preferred are the synthetic pyrethroids.
[0011] Many of these active ingredients are effective both as a pesticide and a repellent, and the activity of many is enhanced by the inclusion of a synergist. Especially preferred synergists include piperonyl butoxide and N-octyl bicycloheptene dicarboximide.
[0012] The active agent and the IDPP are mixed together at a predetermined ratio to form a pre-blend. In one embodiment of the invention, the IDPP/active agent pre-blend is in high concentration in the final pest control system (that is, about 30 wt% or more, preferably about 40 wt% or more, more preferably about 60 wt% or more of the total system). By combining IDPP with the pest control active agent, the irritation to the skin and/or eyes of the active agent to warm blooded animals (including humans) is reduced. This property of the present invention is particularly useful for reducing the irritation of synthetic pyrethroids to warm blooded animals. The amount of IDPP in the formulation relative to the amount of active agent will be an amount effective to reduce the irritation caused by the active agent. The effective amount is easily determinable by routine experimentation. Generally, the amount of IDPP in the formulation should be at least equal to the amount of active agent and, often, the amount of IDPP in the formulation is double to many times the amount of active agent in the formulation in order to reduce the irritation value of the active agent. Thus, the ratio of IDPP:active agent is preferably from about 1:1 to about 99:1.
[0013] To prepare pest control systems according to the invention, the pest control active agent and the IDPP are mixed together to form an active agent/carrier blend (the pre-blend). This pre-blend is then mixed with other ingredients as necessary or desired, depending on the particular active agent chosen and the form and intended use of the final product. The resulting formulation is then processed (and, if necessary, extruded or otherwise shaped) into the desired pest control system.
[0014] For example, if the pest control system is a shaped polymeric article (such as an animal collar, an ear tag, or a pest strip, for example), a polymer or copolymer conventionally employed in such articles (such as polymers and copolymers of vinyl monomers such as polyvinyl chloride, polyvinyl acetate, polyacrylates or the like, or other powdered polymers or copolymers) is mixed with plasticizers and/or stabilizers as necessary, as are known in the art or can be determined without undue experimentation. An IDPP / active agent pre-blend is added to the polymer mixture and combined until a dry free-flowing mix is obtained. Depending on the polymer chosen, it may require a common practice of heating the polymer to expand the particle so as to accept the IDPP/active agent pre-blend and remain a dry free-flowing blend. This mix is then fused together into the desired shape by extruding or molding at the proper temperature and pressure by standard methods known in the art. When the IDPP/active agent combination is maintained as it is released from the article (which can be determined without undue experiementation), the parasthesia of the active agent is reduced.
[0015] When the pest control system is a dust or powder, for example, the pest control active agent/IDPP pre-blend is mixed together with and incorporated into (such as by absorption or adsorption) the appropriate mineral or cellulosic substrate carrier. The carrier may be selected from talc, waxes, corn starch, silica and silica derivatives, clay, diatomaceous earth, corn cob, peanut hulls, paper, and the like, as are known in the art. The dust or powder pest control system is such that it maintains the IDPP/active agent combination as they are released from the system.
[0016] When a liquid pest control system is prepared, the pest control active agent/IDPP pre-blend is mixed together with a suitable organic solvent, an aqueous solvent, or mixtures thereof. The liquid carrier is chosen such that the active agent and the IDPP will remain associated together as a group in the resulting system, which can be determined by those skilled in the art without undue experimentation.
[0017] The following examples illustrate the practice of the present invention. Parts are given as percentages and temperature in degrees Fahrenheit unless otherwise noted. “RT” is room temperature.
EXAMPLES
Example 1
[0018] For purposes of evaluation of the discovery of this invention and to assist in determining the correct ratios of active agent to IDPP, the following screening procedure was set up:
[0019] 1. Different ratios of active ingredient to IDPP are prepared for evaluation.
[0020] 2. A one-gram drop of the ratio is placed on human skin. Only one drop is evaluated within a 24-hour period.
[0021] 3. Irritation or sensitivity values are assigned according to the following scale (“Parasthesia Irritation Rating” or “PIR”):
12=Severe 8 =Noticeable discomfort 4 =Slight discomfort 0=No discomfort
[0026] 4. If irritation is severe or noticeable at any time within a 24-hour period, the skin is washed and 5% lidocaine solution is applied to lessen discomfort.
[0027] The following active agents in combination with IDPP were evaluated according to the above procedure, to demonstrate the discovery of the present invention.
Ratios Cypermethrin 0.67 0.43 0.33 0.25 0.21 0.18 IDPP 1.00 1.00 1.00 1.00 1.00 1.00 Parasthesia Irritation 12.00 12.00 12.00 4.00 0.00 0.00 Rating Ratios Cyphenothrin 1.00 1.50 1.00 0.67 IDPP — 1.00 1.00 1.00 Parasthesia Irritation Rating 12.00 4.00 0.00 0.00
[0028] When formulating, each individual formulation must be evaluated for irritation due to the influence of different actives, additional ingredients (solvents, surfactants, and the like) and/or forms (solids, liquids, dust, emulsion, and the like), which evaluation can be perfomed by those skilled in the art using known methods without undue experimentation.
Example 2
[0029] A Ready-To-Use (RTU) liquid horse spray for flies having the following formulation was prepared by mixing together the cypermethrin and IDPP, and then mixing the resulting pre-blend with the remaining ingredients.
Ingredient Amt. (wt %) Cypermethrin 1.00 Isodiphenyl Phosphate 5.00 Pemulen TR-2 0.20 Ammonia Hydroxide 27% 0.03 Isopropyl Alcohol 21.20 Deionized Water 72.57 Pemulen TR-2 is a polymeric emulsifier made by Noveon, Inc.
[0030] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 3
[0031] A Ready-To-Use (RTU) liquid spot-on for flies was prepared by mixing together the following ingredients:
Ingredient Amt. (wt %) Gokilaht Technical 42.83 Nylar Technical 2.10 Isodiphenyl Phosphate 55.07 Gokilaht (d-cyphenothrin; synthetic pyrethroid) Technical -- MGK Company. Nylar ® insect growth regulator comprises approximately 50% by weight pyriproxyfen and approximately 50% by weight corn oil and is available from MGK Company.
[0032] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 4
[0033] A dust for cattle horn fly having the following formulation was prepared by mixing together the cypermethrin and IDPP, and then mixing the resulting pre-blen with the remaining ingredients.
Ingredient Amt. (wt %) Cypermethrin Technical 1.00 Isodiphenyl Phosphate 5.00 Calcium Silicate 19.40 Kaolin 74.60
[0034] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 5
[0035] A Ready-To-Use (RTU) powder spot-on for small animals for control of external parasites, e.g. fleas and ticks, was prepared by mixing together the following ingredients, the deltamethrin and IDPP having been blended together first to form a pre-blend:
Ingredient Amt. (wt %) Poly Pore L-200 40.00 Deltamethrin 30.00 Isodiphenyl Phosphate 30.00 Poly Pore L-200 is a polyacrylate made by Chemdal Corporation Palatine, IL.
[0036] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 6
[0037] A solid dog collar for fleas and ticks was prepared by mixing together the following ingredients:
Ingredient Amt. (wt %) Polyvinyl Chloride 50.00 Stabilizer (Witco CZ19A) 0.50 Epoxidized Soybean Oil 5.00 Deltamethrin Tech., 98.4% 4.00 Isodiphenyl Phosphate 40.50
[0038] The formulation was blended by charging a ribbon blender with the PVC, stabilizer, and soybean oil, heating to about 150° F., and blending until a dry and flowable blend was obtained. Separately, IDPP and deltamethrin were blended together and heated until deltamethrin went into solution. This IDPP/deltamethrin pre-blend solution was added to the PVC blend and blended until the composition was dry and flowable. The batch was extruded at about 300° F. into collars of a size suitable for use on dogs.
[0039] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 7
[0040] A RTU liquid spray/wipe for large or small animals was prepared by mixing together the following ingredients:
Ingredient Amt. (wt %) Beta Cyfluthrin 1.00 Isodiphenyl Phosphate 99.00
[0041] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 8
[0042] A RTU liquid spray/wipe for large or small animals was prepared by mixing together the following ingredients:
Ingredient Amt. (wt %) Beta Cyfluthrin 1.00 Isodiphenyl Phosphate 20.00 Pemulen TR-2 0.20 Ammonium hydroxide 28% 0.03 Isopropyl alcohol 99% 21.00 Deionized water 54.77 Foraperle 303 3.00 Foraperle 303 is a fluoropolymer made by DuPont.
[0043] The water and isopropyl alcohol were mixed together, after which the Pemulen TR-2 was added and allowed to hydrate. The ammonium hydroxide was added to partially neutralize the Pemulen.
[0044] The beta cyfluthrin and IDPP were mixed together and the resulting pre-blend was added, with good agitation, to the above mixture. After the mixture was blended, the Foraperle was added and mixed in.
[0045] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
Example 9
[0046] A concentrate to be applied to the soil as a termicide was prepared by mixing together the following ingredients:
Ingredient Amt. (wt %) Cyphenothrin 25.00 Isodiphenyl Phosphate 25.00 Pemulen TR-2 0.30 Ammonium hydroxide 28% 0.03 Deionized water 49.67
[0047] The Pemulen was hydrated in the water and partially neutralized with the ammonium hydroxide. The cyphenothrin and IDPP were blended together and added to the water phase while using good agitation to give the liquid termicide concentrate.
[0048] Following the procedure of Example 1, the above formulation was tested for irritation. The PIR was 0.0.
[0049] Using one part of the above concentrate to 25 parts of water gives a dilution that is then applied to the soil as a drench. | The present invention relates to a pest control system which includes a pest control active ingredient and isodecyl diphenyl phosphate as a carrier for the active ingredient. The system releases the active ingredient efficiently and uniformly. The pest control system is less irritating to the animal's skin as compared to prior art systems. The system is useful for making animal collars, ear tags, pest strips, liquid spot-on treatments, and the like. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. nonprovisional patent application Ser. No. 11/846,994, filed on Aug. 29, 2007, now U.S. Pat. No. 7,901,472, which is herein incorporated in its entirety by reference.
FIELD OF THE INVENTION
The invention relates to fuel combustion. More particularly, the invention relates to combustion modifier compositions and methods for improving the combustion efficiency of a vehicle by increasing the efficiency of the internal combustion engine in combusting hydrocarbon fuels.
BACKGROUND
Soaring fuel costs, peaking fuel production and dwindling reserves, conservation efforts, and environmental concerns have increased public awareness of the fuel efficiency issues posed by automobiles and other vehicles. Internal combustion engines are often inefficient in combusting fuel in that they fail to completely burn all of the fuel entering a combustion chamber of the engine. This unburned fuel can remain within the combustion chamber where it forms unburned hydrocarbon residues that accumulate on an interior wall of the combustion chamber as well as other surfaces that play a role in the combustion process. These residues are problematic because, when incinerated, they are discharged as toxic and harmful exhaust emissions such as soot. These unburned hydrocarbons may also react with nitrogen oxides, which are also produced during fuel combustion, upon exposure to ultraviolet light to form ozone. The unburned hydrocarbon residues interfere with fuel combustion and reduce the power output of the engine. Additionally, with the present low levels of sulfur in fuels, the internal combustion engine and its parts such as the exhaust valve experience additional friction that was reduced by the lubricating effects of the sulfur previously found in most hydrocarbon fuels.
Conventional fuel additives may also be disadvantageous due to the necessity of including a carrier or substrate that may permit the active ingredients of those products to attach to the interior surface of the combustion chamber of the internal combustion engine. Carriers and substrates in these conventional fuel additives may include toxic compounds that increase production costs and harm the environment when emitted in vehicle exhaust emissions. The failure of many conventional fuel additives to coat the combustion chamber's interior surface to prevent the formation and accumulation of residues thereon decreases the efficiency of the engine in combusting fuel. Less fuel is combusted by the engine and more fuel is wasted as combustion by-product residues that are deposited onto the interior surface of the combustion chamber.
Another disadvantage of conventional fuel additives is that many include precious metals such as platinum to act as catalysts. The use of catalytically-active precious metals is undesirable due to the high costs of production of such fuel additives.
An additional disadvantage of conventional fuel additives is that many are water soluble and cannot be dissolved in oil. The insolubility of many conventional fuel additives in oil reduces the effectiveness of the fuel additives in improving fuel efficiency. Oil-insoluble conventional fuel additives must be mixed with an oil-soluble compound prior to use, thereby increasing the cost of production. Conventional fuel additives may also include other environmentally-harmful compounds, such as naphthalene, which may be toxic to animals, plants, humans, and other organisms.
Another disadvantage of many conventional fuel additives is their failure to reduce the emissions of volatile organic compounds (VOCs) and nitrogen oxides in vehicle exhaust, which are produced as byproducts of fuel combustion. Both VOCs and nitrogen oxides undergo a chemical reaction in the lower atmosphere upon exposure to ultraviolet light to form ozone, which is a hazardous smog-forming pollutant that has been linked to respiratory illnesses and lung tissue damage in humans.
Conventional fuel additives have not included a source of boron because many boron-containing compounds create a thin layer of boron oxide that deposits on the combustion surfaces of an internal combustion engine. This thin layer of boron oxide produces longer ignition delays, and thus, reduces combustion efficiency.
Conventional fuel additives have also not included a source of cerium because most conventional fuel additives work as detergents or solvents to physically affect fuel in an effort to increase the efficiency of combustion. In addition, many cerium-containing compounds have proven difficult or disadvantageous for usage in fuel additives, and thus, have been avoided by the makers of conventional fuel additives, due to the undesirable byproducts precipitated from ceric salts and cerous salts used to produce cerium metal. Ceric salts that are undesirable for producing cerium metal to be used in fuel additives include ceric fluoride, ceric oxide, and ceric sulfate. Cerous salts that are undesirable for producing cerium metal to be used in fuel additives include cerous bromide, cerous carbonate, cerous chloride, cerous fluoride, cerous iodide, cerous nitrate, cerous oxalate, and cerous sulfate. These ceric and cerous salts are not solvent-soluble and do not yield cerium metal with a high level of purity. Cerium metal derived from these ceric and cerous salts is not oil-soluble and must be finely ground into nanoparticles and complexed with a fuel-soluble compound before introduction into an internal combustion engine. The production of nanoparticles of cerium metal would greatly increase the costs of producing cerium-containing fuel additives using conventional technologies.
SUMMARY
The present invention relates to the discovery that certain organometallic soaps, when added to fuel, achieve several advantageous effects with respect to the combustion of fuel in an internal combustion engine. These organometallic soaps, which are soluble in fuel products derived from petroleum oil as well as in other hydrocarbon fuels, may contain ferric iron or cerium (III). The organometallic soap or soaps can be selected from among the following ferric and cerous compounds: cerium ammoniate, cerium ureate, cerium nitrate, cerium-2-ethylhexanoate, cerium octoate, cerium stearate, cerium naphthenate, cerium salicylate, cerium carbonate, ferric octoate, ferric-2-ethylhexanoate, ferric stearate, ferric naphthenate, ferric salicylate, ferric carbonate, diborylated ferrocene, n-butyl ferrocene, 1,1′-dimethyl ferrocene, benzoyl ferrocene, and combinations thereof. Each organometallic soap, alone or in combination with one or more other organometallic soaps, can be used as a combustion modifier that can be introduced into the internal combustion engine to increase the engine's fuel combustion efficiency.
The ferric compounds increase the efficiency of fuel combustion in internal combustion engines by creating a catalytic residue that coats an interior surface of the engine's combustion chamber. Upon combustion, diborylated ferrocene, for example, forms an iron-boron complex catalytic coating on the interior surface of the combustion chamber to create a sacrificial catalytic coating. The catalytic coating formed by the diborylated ferrocene, which is a fullerene, prevents faulty combustion caused by the accumulation of carbon deposits on the interior surface of the combustion chamber. The ferric compounds, and diborylated ferrocene in particular, also act as lubricants to replace the lubricating effect lost by the reduction of sulfur content in low-sulfur diesel fuels. The lubricating effect of the combustion modifier reduces wear of the exhaust valve seat. Like the lead that was formerly present in some fuels, the ferric compound of the combustion modifier can replace the anti-knocking effects now lost in unleaded fuels. The ferric compound of the combustion modifier can act as an anti-knocking agent to reduce or eliminate engine “knocking” By increasing the efficiency of the internal combustion engine in combusting fuel, the ferric compound of the combustion modifier also increases engine power, which, in turn, enhances the torque and fuel economy of the engine.
Diborylated ferrocene, in particular, is advantageous for use as the ferric compound in the combustion modifier. The compound includes at least one diboryl ring and at least two ferrocene units. Advantages are derived from boron's low molecular weight and high energy of combustion, which make boron an attractive additive for use in high-energy fuels such as rocket propellants. When complexed with an iron compound as in, for example, diborylated ferrocene, the boron does not produce a boron oxide layer on the combustion surfaces of the internal combustion engine thereby eliminating any negative effects produced by the formation of such a layer. In addition, the catalytic coating created by the boron-iron complex is a far superior catalyst in comparison to either an iron coating or a boron coating individually.
Diborylated ferrocene is a stable, neutral fullerene structure compound. The diborylated ferrocene dimer is able to undergo reversible conformational changes promoted by both reduction and oxidation (redox) reactions when exposed to combustion of the fuels to which it is added. Diborylated ferrocene exhibits strong boron-iron electronic interactions, and when exposed to combustion temperatures, it can undergo reduction at the diboryl ring or oxidation at the ferrocene unit. The diboryl ring sits slightly tilted in a plane between the ferrocene molecules, however, when the diborylated ferrocene is oxidized or reduced, the diboryl ring flattens in the plane. This flattening effect pushes the iron atoms of the ferrocene molecules farther apart and makes available the advantageous catalytic features inherent to both the ferrocene molecule and the boron molecule.
The cerous compounds act as catalytic oxidizers to quicken the combustion rate of the fuel in the internal combustion engine. The cerous compounds achieve this effect by exciting fuel molecules to move farther apart from one another thereby producing smaller fuel droplets. By increasing the surface-to-volume ratio of the fuel, the smaller fuel droplets combust more quickly and efficiently than fuel that does not contain the composition. The cerous compounds also reduce the ignition delay, which is the time elapsing between the application of a spark and the combustion of the fuel. Addition of one or more of the cerous compounds to the composition can reduce the ignition delay for fuel to which the composition has been added by about 1 to 4 milliseconds.
The present methods for making cerium-containing compounds is advantageous because the cerous compounds produced by these methods are reactant and oil-soluble and do not require grinding to produce fine, nanosized particles that must be complexed with fuel-soluble compounds. By eliminating the need to produce nanoparticles of cerium, the present methods reduce the cost of production of cerous combustion modifier compounds. Cerous nitrogen-containing compounds, e.g., cerium ureate, cerium ammoniate, and cerium nitrate, can be used in combination with fuel to modify the fuel's combustion rate. The cerous compounds produced by these methods can include nitrate, ammonia, or urea to enhance the combustion rate of fuel, thereby increasing fuel efficiency and reducing the production of nitrogen oxides from nitrogen compounds present in the fuel.
The organometallic soap can be mixed with a hydrocarbon fuel to improve the efficiency of the internal combustion engine, and in particular, the internal combustion engine of a vehicle, in combusting hydrocarbon fuels. For example, the organometallic soap and fuel mixture may increase the rate of fuel combustion in the engine and improve the efficiency of the engine in generating power. In one example, the combustion efficiency of an internal combustion engine increased almost 40 percent with the addition of the organometallic soap to fuel supplied to the engine for combustion. The organometallic soaps of this invention also coat the interior surface of the combustion chamber and other combustion parts of the internal combustion engine to reduce the accumulation of carbon residues therein. The mixture of fuel and organometallic soaps may also act to reduce toxic emissions released in exhaust fumes produced by the engine. Use of the composition by introduction into the internal combustion engine significantly increases combustion efficiency by increasing the amount of fuel combusted by the engine and by reducing the amount of fuel that fails to fully combust inside the engine. The composition may also reduce the accumulation of carbon residues, including soot, by preventing their deposition on the interior surface of the combustion chamber during the breakdown of hydrocarbon fuels.
The production of pollutants, including nitrogen oxides and VOCs, can also be reduced by the use of organometallic soaps. The combustion modifier may act to reduce the production of these compounds by improving the efficiency of fuel combustion so that less waste products are generated and also by incorporating a nitrogen-containing component such as cerium ammoniate or cerium ureate. By reducing the production of these waste products of inefficient fuel combustion, the combustion modifier also indirectly reduces the formation of ozone in the atmosphere by decreasing the emissions of ozone's precursor chemicals, e.g., VOCs and nitrogen oxides.
In comparison with conventional fuel additives, the organometallic soaps of this invention also present a significant advantage over many conventional fuel additives due to the solubility of the organometallic soaps in oil.
Accordingly, the invention features a composition for improving the combustion efficiency of an internal combustion engine in combusting hydrocarbon fuels. The composition may include a hydrocarbon fuel and a combustion modifier. The combustion modifier can include an organometallic soap selected from the group consisting of: cerium-2-ethylhexanoate, cerium octoate, cerium stearate, cerium naphthenate, cerium salicylate, cerium carbonate, cerium ammoniate, cerium ureate, cerium nitrate, ferric octoate, ferric-2-ethylhexanoate, ferric stearate, ferric naphthenate, ferric salicylate, ferric carbonate, diborylated ferrocene, n-butyl ferrocene, 1,1′-dimethyl ferrocene, benzoyl ferrocene, and combinations thereof.
In another aspect, the invention features as the organometallic soap a compound selected from the group consisting of: cerium octoate, cerium ammoniate, cerium ureate, and cerium-2-ethylhexanoate.
In another aspect, the invention features diborylated ferrocene as the organometallic soap.
In another aspect, the invention features as the combustion modifier a mixture of diborylated ferrocene and a compound selected from the group consisting of: cerium-2-ethylhexanoate and cerium octoate.
In another aspect, the invention features as the combustion modifier a mixture of diborylated ferrocene and a compound selected from the group consisting of: cerium ammoniate and cerium ureate.
In another aspect, the invention features as the combustion modifier diborylated ferrocene in the range of 10 to 100 percent by weight.
In another aspect, the invention features as the combustion modifier cerium-2-ethylhexanoate in the range of 10 to 100 percent by weight.
In another aspect, the invention features as the combustion modifier a mixture of diborylated ferrocene and cerium-2-ethylhexanoate wherein one of the compounds comprises 10 to 100 percent by weight of the combustion modifier with the other compound forming the remaining balance.
In another aspect, the invention features as the combustion modifier a mixture of 70 percent by weight diborylated ferrocene and 30 percent by weight cerium-2-ethylhexanoate.
In another aspect, the invention features as the combustion modifier a mixture of diborylated ferrocene at 70 percent by weight and 30 percent by weight of an organometallic soap selected from the group consisting of cerium ammoniate and cerium ureate.
In another aspect, the invention features the combustion modifier as a liquid.
In another aspect, the invention features the organometallic soap dissolved in a solvent blend comprising Solvent 142, dibasic ester, and propylene glycol mono-n-butyl ether.
In another aspect, the invention features as the combustion modifier a mixture of about 4 percent by weight organometallic soap, about 81 percent by weight Solvent 142, about 10 percent by weight dibasic ester, and about 5 percent by weight propylene glycol mono-n-butyl ether.
In another aspect, the invention features as the combustion modifier a mixture of diborylated ferrocene at 40 to 60 percent by weight and a cerous compound at 40 to 60 percent by weight wherein the cerous compound is selected from one of the group consisting of cerium ammoniate and cerium ureate.
The invention also features a method which includes the step of introducing into an internal combustion engine a hydrocarbon fuel and a combustion modifier. The combustion modifier of the method includes an organometallic soap selected from the group consisting of: cerium-2-ethylhexanoate, cerium octoate, cerium stearate, cerium naphthenate, cerium salicylate, cerium carbonate, cerium ammoniate, cerium ureate, cerium nitrate, ferric octoate, ferric-2-ethylhexanoate, ferric stearate, ferric naphthenate, ferric salicylate, ferric carbonate, diborylated ferrocene, n-butyl ferrocene, 1,1′-dimethyl ferrocene, benzoyl ferrocene, and combinations thereof.
Another method of the invention includes the step of supplying the combustion modifier into a fuel tank, which is connected to the internal combustion engine, in an amount of about 0.01 to 5 grams per about 20 gallons of fuel.
Another method of the invention includes the step of supplying the combustion modifier into a fuel tank, which is connected to the internal combustion engine, in an amount of about 0.01 to 3 grams per about 20 gallons of fuel
Another method of the invention includes the step of supplying the combustion modifier into a fuel tank, which is connected to the internal combustion engine, in an amount of about 0.25 to 1 gram per about 20 gallons of fuel.
The invention further features a method for producing a combustion modifier that includes the steps of: (a) mixing a cerium compound with a first acid and with a compound selected from the group consisting of: a salt of a second acid, an ester of the second acid, a salt of urea, an ester of urea, a salt of ammonia, and an ester of ammonia, to produce a mixture; (b) heating the mixture while placing the mixture under pressure less than standard atmospheric pressure; (c) heating the mixture while placing the mixture under pressure of about 30 inches of mercury; and (d) cooling the mixture to yield a combustion modifier.
Another method of the invention includes the step of selecting and using a synthetic mono-carboxylic acid as the first acid.
Another method of the invention includes the step of adding a ferric organometallic soap to the mixture before step (c) of the method.
Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. In the case of conflict, the present specification, including definitions will control.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a chart representing fuel pounds per hour measurements for a control test in which diesel fuel was combusted in an internal combustion engine without the addition of a combustion modifier of the invention.
FIG. 1B is a chart representing measurements of air consumed by fuel combustion for a control test in which diesel fuel was combusted in the internal combustion engine without the addition of a combustion modifier of the invention.
FIG. 2A is a chart representing fuel pounds per hour measurements for an experimental test in which diesel fuel was combusted in an internal combustion engine to which a combustion modifier of the invention was supplied.
FIG. 2B is a chart representing measurements of air consumed by fuel combustion for an experimental test in which diesel fuel was combusted in the internal combustion engine to which a combustion modifier of the invention was supplied.
DETAILED DESCRIPTION
The invention provides a composition for improving the combustion efficiency of an internal combustion engine, and in particular, the internal combustion engine of a vehicle, in combusting hydrocarbon fuels. The composition includes a mixture of a hydrocarbon fuel and a combustion modifier that contains an organometallic soap. The organometallic soap may contain ferric iron or cerium (III). The organometallic soap of the combustion modifier can be selected from among the following ferric and cerous organometallic soap compounds: cerium ammoniate, cerium ureate, cerium nitrate, cerium-2-ethylhexanoate, cerium octoate, cerium stearate, cerium naphthenate, cerium salicylate, cerium carbonate, ferric octoate, ferric-2-ethylhexanoate, ferric stearate, ferric naphthenate, ferric salicylate, ferric carbonate, diborylated ferrocene, n-butyl ferrocene, 1,1′-dimethyl ferrocene, benzoyl ferrocene, and combinations thereof. The combustion modifier can include 1, 2, 3, 4, 5, or more of the organometallic soaps. The organometallic soap is soluble in fuel products derived from petroleum oil as well as in other hydrocarbon fuels.
Hydrocarbon fuels with which the combustion modifier can be mixed include, for example, (1) petroleum-derived fossil fuels such as gasoline, diesel, jet fuel, fuel oil, and kerosene; (2) biofuels such as bioethanol, biodiesel, straight vegetable oils (pure plant oils), and waste vegetable oils; and (3) combinations thereof.
In one embodiment, the organometallic soap can be diborylated ferrocene only although the combustion modifier preferably also contains a cerous compound for increasing the combustion rate of the fuel in the internal combustion engine. In another embodiment of the composition, the combustion modifier may include only a single ferric iron-containing organometallic soap selected from among those described herein.
In another embodiment, the organometallic soap can be cerium-2-ethylhexanoate only although the combustion modifier preferably also contains a ferric compound for increasing the combustion rate of the fuel in the internal combustion engine by preventing the accumulation of carbon residues on the internal surface of the combustion chamber of the internal combustion engine. In another embodiment of the composition, the combustion modifier may include only a single cerium-containing organometallic soap selected from among those described herein.
In another embodiment, the combustion modifier can include a mixture of one or more ferric compounds selected from among those described herein and one or more cerous compounds selected from among those described herein. The combustion modifier may include the ferric compound or mixture of compounds in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and the cerous compound or mixture of compounds in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The combustion modifier can also include the ferric compound or mixture of compounds in a range of about 15 to 85, about 35 to 75, or about 65 to 75 percent by weight and the cerous compound or mixture of compounds in a range of about 15 to 85, about 25 to 65, or about 25 to 35 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight ferric compound or compounds and about 30 percent by weight cerous compound or compounds.
In another embodiment, the combustion modifier can include a mixture of n-butyl ferrocene, 1,1′-dimethyl ferrocene, or benzoyl ferrocene and one or more cerous compounds selected from among those described herein. The combustion modifier may include at least one of n-butyl ferrocene, 1,1′-dimethyl ferrocene, or benzoyl ferrocene in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and the cerous compound or mixture of compounds in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The combustion modifier can also include at least one of n-butyl ferrocene, 1,1′-dimethyl ferrocene, or benzoyl ferrocene in a range of about 15 to 85, about 35 to 75, or about 65 to 75 percent by weight and the cerous compound or mixture of compounds in a range of about 15 to 85, about 25 to 65, or about 25 to 35 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight of at least one of n-butyl ferrocene, 1,1′-dimethyl ferrocene, or benzoyl ferrocene and about 30 percent by weight cerous compound or compounds.
In another embodiment, the combustion modifier can include a mixture of cerium-2-ethylhexanoate and diborylated ferrocene. In this embodiment, the combustion modifier may include diborylated ferrocene in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and cerium-2-ethylhexanoate in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The combustion modifier can also include diborylated ferrocene in a range of about 15 to 85, about 35 to 75, or about 65 to 75 percent by weight and cerium-2-ethylhexanoate in a range of about 15 to 85, about 25 to 65, or about 25 to 35 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight diborylated ferrocene and about 30 percent by weight cerium-2-ethylhexanoate.
In a preferred embodiment, the combustion modifier can be a mixture of diborylated ferrocene and cerium octoate. In this embodiment, the combustion modifier may include diborylated ferrocene in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and cerium octoate in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The combustion modifier can also include diborylated ferrocene in a range of about 15 to 85, about 35 to 75, or about 65 to 75 percent by weight and cerium octoate in a range of about 15 to 85, about 25 to 65, or about 25 to 35 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight diborylated ferrocene and about 30 percent by weight cerium octoate. This embodiment of the composition is preferred because of the high combustion efficiency and combustion rate achieved by use of the combustion modifier during testing.
In the most preferred embodiments, the combustion modifier can be a mixture of diborylated ferrocene and cerium ammoniate or a mixture of diborylated ferrocene and cerium ureate. The mixtures of compounds contained in these embodiments of the composition may reduce nitrogen oxide emissions produced by combustion of the fuel. These embodiments of the composition are most preferred because, during testing, these embodiments of the combustion modifier achieved the highest combustion efficiency and combustion rates. The combustion modifier may include diborylated ferrocene in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and either cerium ammoniate or cerium ureate in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight diborylated ferrocene and about 30 percent by weight cerium ammoniate or cerium ureate. In other embodiments, the combustion modifier may include diborylated ferrocene in a range of about 15 to 85, about 40 to 60, about 35 to 75, or about 65 to 75 percent by weight with the remainder of the composition including either cerium ammoniate or cerium ureate in a range of about 15 to 85, about 40 to 60, about 25 to 65, or about 25 to 35 percent by weight.
In an alternate embodiment of the invention, the combustion modifier can include a mixture of diborylated ferrocene and both cerium ammoniate and cerium ureate. In this embodiment, the combustion modifier can include diborylated ferrocene in a range of about 10 to 100 percent by weight or about 60 to 80 percent by weight and a mixture of both cerium ammoniate and cerium ureate in a range of about 10 to 100 percent by weight or about 20 to 40 percent by weight. The mixture of cerium ammoniate and cerium ureate may contain cerium ammoniate in a range of about 0.001 to 99.999 percent by weight and cerium ureate in a range of about 0.001 to 99.999 percent by weight. In other embodiments, the combustion modifier can include diborylated ferrocene in a range of about 15 to 85, about 40 to 60, about 35 to 75, or about 65 to 75 percent by weight with the remainder of the composition including a mixture of both cerium ammoniate and cerium ureate in a range of about 15 to 85, about 40 to 60, about 25 to 65, or about 25 to 35 percent by weight. The combustion rate and combustion efficiency are most improved when the combustion modifier contains about 70 percent by weight diborylated ferrocene and about 30 percent by weight of the mixture of cerium ammoniate and cerium ureate.
The combustion modifier may be a solid in the form of a pill, caplet, tablet, powder, bar, block, or amorphous form. The combustion modifier may also be manufactured as a liquid or gel. In one embodiment, the combustion modifier can be manufactured to include nanophase particles of the organometallic soap.
To produce the combustion modifier as a liquid, the organometallic soap can be dissolved in a solvent blend comprising Solvent 142, dibasic ester, and propylene glycol mono-n-butyl ether. Solvent 142 is a heavy hydrotreated petroleum with a flashpoint above 142 degrees Fahrenheit, which includes a mixture of predominantly aliphatic hydrocarbons (for example, paraffins and cycloparaffins) having hydrocarbon chain lengths predominantly in the range of C9 through C12. In other embodiments, the solvent blend may include about 0.1 to 10, about 3 to 7, about 3.5 to 5, or about 4 to 6 percent by weight organometallic soap; about 70 to 90, about 75 to 85, about 77 to 83, or about 80 to 82 percent by weight Solvent 142; about 5 to 15, about 7 to 11, or about 8.5 to 10 percent by weight dibasic ester; and about 1 to 10, about 4 to 6, or about 4.5 to 5.5 percent by weight propylene glycol mono-n-butyl ether. In another embodiment, the solvent blend may include about 2 to 8 percent by weight organometallic soap, about 73 to 89 percent by weight Solvent 142, about 6 to 12 percent by weight dibasic ester, and about 3 to 7 percent by weight propylene glycol mono-n-butyl ether. In an exemplary embodiment, the blend may include about 4 percent by weight organometallic soap, about 81 percent by weight Solvent 142, about 10 percent by weight dibasic ester, and about 5 percent by weight propylene glycol mono-n-butyl ether.
Method for Making
The invention features methods for making a combustion modifier that can be introduced into a fuel tank feeding an internal combustion engine to improve the efficiency of fuel combustion in the internal combustion engine. In one step of the method, cerium can be mixed and reacted with a synthetic mono-carboxylic acid and with a salt or ester of a second acid, e.g., 2-ethylhexanoic acid, octoic acid, stearic acid, naphthenic acid, salicylic acid, carbonic acid, or nitric acid. Other cerium-containing compounds can be substituted for the elemental cerium for reaction with the mono-carboxylic acid. Other acids and acid blends, including natural mono-carboxylic acids, can also be used to produce less effective combustion modifier compositions.
In another embodiment, a salt of ammonia or urea or an ester of ammonia or urea may be substituted in place of the salt or ester of the second acid.
In another embodiment of the method, the second acid, e.g., 2-ethylhexanoic acid, may itself be reacted with cerium in place of the salt or ester of the second acid. In this embodiment, if the second acid utilized for the reaction with cerium is a carboxylic acid, such as 2-ethylhexanoic acid, octoic acid, stearic acid, naphthenic acid, or salicylic acid, the addition of a mono-carboxylic acid is not required.
The cerium-containing compound and acid are heated and mixed in a reactor to form a mixture that may include any of the following cerous organometallic soap compounds: cerium-2-ethylhexanoate, cerium octoate, cerium stearate, cerium naphthenate, cerium salicylate, cerium carbonate, cerium ammoniate, cerium ureate, cerium nitrate, and combinations thereof.
In another step of the method, a ferric compound (e.g., ferric octoate, ferric-2-ethylhexanoate, ferric stearate, ferric naphthenate, ferric salicylate, ferric carbonate, diborylated ferrocene, n-butyl ferrocene, 1,1′-dimethyl ferrocene, benzoyl ferrocene, or combinations thereof) can be added to the mixture.
In another step of the method, the mixture is placed under a pressure of about 20 inches of mercury (e.g., 15, 18, 19, 19.5, 19.9, 20, 20.1, 20.5, 21, 22, or 25 inches of mercury) while heat continues to be applied. Then, the mixture is placed under a pressure of about 30 inches of mercury (e.g., 25, 28, 29, 29.5, 29.9, 29.92, 30, 30.1, 30.5, 31, 32, or 35 inches of mercury) while continuing to be heated.
In another step of the method, the mixture undergoes cooling prior to packaging to yield a combustion modifier.
Method for Using
The invention also features methods for improving the efficiency of fuel combustion in an internal combustion engine. In one embodiment of the method, a composition containing a mixture of a hydrocarbon fuel and a combustion modifier containing an organometallic soap is introduced into a fuel tank feeding an internal combustion engine. In an exemplary embodiment of the method, the combustion modifier is introduced into the fuel tank of the internal combustion engine through a fuel line.
In another embodiment of the method, the combustion modifier may be premixed with the hydrocarbon fuel and subsequently introduced into the fuel tank of the internal combustion engine. In another embodiment of the method, the combustion modifier may be introduced into the fuel tank, directly into the combustion chamber, or into both the fuel tank and combustion chamber using a pump or another suitable system for supplying the combustion modifier into the internal combustion engine.
The internal combustion engine into which the combustion modifier is introduced can be a reciprocating engine (e.g., a diesel engine, a two-stroke engine, a four-stroke engine, a five-stroke engine, a six-stroke engine, a crude oil engine, a hot bulb engine, a controlled combustion engine, or a Bourke engine), a rotary engine (e.g., a Wankel engine), or a continuous combustion engine (e.g., a gas turbine, a jet engine, or a rocket engine). The internal combustion engine may use any suitable form of combustion such as homogeneous charge spark ignition, stratified charge compression ignition, or homogeneous charge compression ignition. In one embodiment, the fuel tank into which the composition is introduced may be part of a vehicle such as an automobile, a truck, a motorcycle, an aircraft, a personal watercraft, a boat, a bus, an all-terrain vehicle (ATV), a motorized go-cart, a motorized bicycle, a tractor, a lawn mower, a locomotive, an engineering vehicle, or a scooter. In another embodiment the fuel tank into which the composition is introduced can be part of a generator.
In one embodiment of the method, the combustion modifier is supplied into the fuel tank in an amount of about 0.01 to 5 grams (e.g., 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 3, 4, 4.9, 5, or 5.5 grams) per about 20 gallons of fuel.
In an exemplary embodiment of the method, the combustion modifier is supplied into the fuel tank in an amount of about 0.01 to 3 grams (e.g., 0.01, 0.05, 0.1, 0.5, 1, 1.5, 2, 2.9, 3, or 3.5 grams) per about 20 gallons of fuel.
In a preferred embodiment of the method, the combustion modifier is supplied into the fuel tank in an amount of about 0.25 to 1 gram (e.g., 0.1, 0.3, 0.5, 0.9, 1, 1.1, or 1.5 grams) per about 20 gallons of fuel.
EXAMPLE
By adding the combustion modifier to the fuel in an automobile or other vehicle's internal combustion engine, the combustion efficiency of that internal combustion engine may be significantly improved. During testing, diesel fuel was combusted in an internal combustion engine first without the introduction of the combustion modifier (the control test shown in FIGS. 1A and 1B ) and then with the introduction of the combustion modifier (the experimental test shown in FIGS. 2A and 2B ). The combustion modifier used in the experimental test was a mixture of 70 percent by weight diborylated ferrocene and 30 percent by weight cerium-2-ethylhexanoate. The fuel pounds per hour combusted by the internal combustion engine was measured and the air/fuel ratio was calculated from the amounts of air and fuel used in a given time period. The internal combustion engine was operated at the same horsepower during both tests and measurements were taken at intervals of about one to two minutes.
In the control test, diesel fuel was burned in an internal combustion engine in the absence of the combustion modifier. Approximately 10.8 to 11.1 fuel pounds per hour of diesel fuel were combusted by the internal combustion engine in the absence of the combustion modifier. The air/fuel ratio for the control test fell within a range of about 52 to about 54.
In the experimental test, the combustion modifier was added to diesel fuel supplied to an internal combustion engine and the fuel pounds per hour was measured and the air/fuel ratio calculated. As shown in FIGS. 1A and 1B , approximately 6.0 to 6.3 fuel pounds per hour were combusted by the internal combustion engine to which the combustion modifier was supplied. The air/fuel ratio in this experimental test fell within a range of about 99 to about 105. The amount of fuel combusted by the internal combustion engine in the presence of the combustion modifier was about 40 percent less than the amount of fuel combusted by the engine during the control test.
Other Embodiments
It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims. | A composition for improving the combustion efficiency of an internal combustion engine. The composition includes a mixture of a hydrocarbon fuel and an organometallic soap selected from among several cerium-containing and ferric compounds. The cerium-containing compound or compounds increase the energy released during combustion of the fuel. The ferric compound or compounds coat an interior wall of a combustion chamber of the internal combustion engine to increase the power output of the engine by reducing the accumulation of residues deposited on the interior wall which interfere with the combustion of fuel. | 2 |
BACKGROUND OF THE INVENTION
This invention relates generally to movable barrier operators for operating movable barriers or doors. More particularly, it relates to garage door operators having improved safety and energy efficiency features.
Garage door operators have become more sophisticated over the years providing users with increased convenience and security. However, users continue to desire further improvements and new features such as increased energy efficiency, ease of installation, automatic configuration, and aesthetic features, such as quiet, smooth operation.
In some markets energy costs are significant. Thus energy efficiency options such as lower horsepower motors and user control over the worklight functions are important to garage door operator owners. For example, most garage door operators have a worklight which turns on when the operator is commanded to move the door and shuts off a fixed period of time after the door stops. In the United States, an illumination period of 4½ minutes is considered adequate. In markets outside the United States, 4½ minutes is considered too long. Some garage door operators have special safety features, for example, which enable the worklight whenever the obstacle detection beam is broken by an intruder passing through an open garage door. Some users may wish to disable the worklight in this situation. There is a need for a garage door operator which can be automatically configured for predefined energy saving features, such as worklight shut-off time.
Some movable barrier operators include a flasher module which causes a small light to flash or blink whenever the barrier is commanded to move. The flasher module provides some warning when the barrier is moving. There is a need for an improved flasher unit which provides even greater warning to the user when the barrier is commanded to move.
Another feature desired in many markets is a smooth, quiet motor and transmission. Most garage door operators have AC motors because they are less expensive than DC motors. However, AC motors are generally noisier than DC motors.
Most garage door operators employ only one or two speed of travel. Single speed operation, i.e., the motor immediately ramps up to full operating speed, can create a jarring start to the door. Then during closing, when the door approaches the floor at full operating speed, whether a DC or AC motor is used, the door closes abruptly with a high amount of tension on it from the inertia of the system. This jarring is hard on the transmission and the door and is annoying to the user.
If two operating speeds are used, the motor would be started at a slow speed, usually 20 percent of full operating speed, then after a fixed period of time, the motor speed would increase to full operating speed. Similarly, when the door reaches a fixed point above/below the close/open limit, the operator would decrease the motor speed to 20 percent of the maximum operating speed. While this two speed operation may eliminate some of the hard starts and stops, the speed changes can be noisy and do not occur smoothly, causing stress on the transmission. There is a need for a garage door operator which opens the door smoothly and quietly, with no aburptly apparent sign of speed change during operation.
Garage doors come in many types and sizes and thus different travel speeds are required for them. For example, a one-piece door will be movable through a shorter total travel distance and needs to travel slower for safety reasons than a segmented door with a longer total travel distance. To accommodate the two door types, many garage door operators include two sprockets for driving the transmission. At installation, the installer must determine what type of door is to be driven, then select the appropriate sprocket to attach to the transmission. This takes additional time and if the installer is the user, may require several attempts before matching the correct sprocket for the door. There is a need for a garage door operator which automatically configures travel speed depending on size and weight of the door.
National safety standards dictate that a garage door operator perform a safety reversal (auto-reverse) when an object is detected only one inch above the DOWN limit or floor. To satisfy these safety requirements, most garage door operators include an obstacle detection system, located near the bottom of the door travel. This prevents the door from closing on objects or persons that may be in the door path. Such obstacle detection systems often include an infrared source and detector located on opposite sides of the door frame. The obstacle detector sends a signal when the infrared beam between the source and detector is broken, indicating an obstacle is detected. In response to the obstacle signal, the operator causes an automatic safety reversal. The door stops and begins traveling up, away from the obstacle.
There are two different “forces” used in the operation of the garage door operator. The first “force” is usually preset or setable at two force levels: the UP force level setting used to determine the speed at which the door travels in the UP direction and the DOWN force level setting used to determine the speed at which the door travels in the DOWN direction. The second “force” is the force level determined by the decrease in motor speed due to an external force applied to the door, i.e., from an obstacle or the floor. This external force level is also preset or setable and is any set-point type force against which the feedback force signal is compared. When the system determines the set point force has been met, an auto-reverse or stop is commanded.
To overcome differences in door installations, i.e. stickiness and resistance to movement and other varying frictional-type forces, some garage door operators permit the maximum force (the second force) used to drive the speed of travel to be varied manually. This, however, affects the system's auto-reverse operation based on force. The auto-reverse system based on force initiates an auto-reverse if the force on the door exceeds the maximum force setting (the second force) by some predetermined amount. If the user increases the force setting to drive the door through a “sticky” section of travel, the user may inadvertently affect the force to a much greater value than is safe for the unit to operate during normal use. For example, if the DOWN force setting is set so high that it is only a small incremental value less than the force setting which initiates an auto-reverse due to force, this causes the door to engage objects at a higher speed before reaching the auto-reverse force setting. While the obstacle detection system will cause the door to auto-reverse, the speed and force at which the door hits the obstacle may cause harm to the obstacle and/or the door.
Barrier movement operators should perform a safety reversal off an obstruction which is only marginally higher than the floor, yet still close the door safely against the floor. In operator systems where the door moves at a high speed, the relatively large momentum of the moving parts, including the door, accomplishes complete closure. In systems with a soft closure, where the door speed decreases from full maximum to a small percentage of full maximum when closing, there may be insufficient momentum in the door or system to accomplish a full closure. For example, even if the door is positioned at the floor, there is sometimes sufficient play in the trolley of the operator to allow the door to move if the user were to try to open it. In particular, in systems employing a DC motor, when the DC motor is shut off, it becomes a dynamic brake. If the door isn't quite at the floor when the DOWN travel limit is reached and the DC motor is shut off, the door and associated moving parts may not have sufficient momentum to overcome the braking force of the DC motor. There is a need for a garage door operator which closes the door completely, eliminating play in the door after closure.
Many garage door operator installations are made to existing garage doors. The amount of force needed to drive the door varies depending on type of door and the quality of the door frame and installation. As a result, some doors are “stickier” than others, requiring greater force to move them through the entire length of travel. If the door is started and stopped using the full operating speed, stickiness is not usually a problem. However, if the garage door operator is capable of operation at two speeds, stickiness becomes a larger problem at the lower speed. In some installations, a force sufficient to run at 20 percent of normal speed is too small to start some doors moving. There is a need for a garage door operator which automatically controls force output and thus start and stop speeds.
SUMMARY OF THE INVENTION
A movable barrier operator having an electric motor for driving a garage door, a gate or other barrier is operated from a source of AC current. The movable barrier operator includes circuitry for automatically detecting the incoming AC line voltage and frequency of the alternating current. By automatically detecting the incoming AC line voltage and determining the frequency, the operator can automatically configure itself to certain user preferences. This occurs without either the user or the installer having to adjust or program the operator. The movable barrier operator includes a worklight for illuminating its immediate surroundings such as the interior of a garage. The barrier operator senses the power line frequency (typically 50 Hz or 60 Hz) to automatically set an appropriate shut-off time for a worklight. Because the power line frequency in Europe is 50 Hz and in the U.S. is 60 Hz, sensing the power line frequency enables the operator to configure itself for either a European or a U.S. market with no user or installer modifications. For U.S. users, the worklight shut-off time is set to preferably 4½ minutes; for European users, the worklight shut-off time is set to preferably 2½ minutes. Thus, a single barrier movement operator can be sold in two different markets with automatic setup, saving installation time.
The movable barrier operator of the present invention automatically detects if an optional flasher module is present. If the module is present, when the door is commanded to move, the operator causes the flasher module to operate. With the flasher module present, the operator also delays operation of the motor for a brief period, say one or two seconds. This delay period with the flasher module blinking before door movement provides an added safety feature to users which warns them of impending door travel (e.g. if activated by an unseen transmitter).
The movable barrier operator of the present invention drives the barrier, which may be a door or a gate, at a variable speed. After motor start, the electric motor reaches a preferred initial speed of 20 percent of the full operating speed. The motor speed then increases slowly in a linearly continuous fashion from 20 percent to 100 percent of full operating speed. This provides a smooth, soft start without jarring the transmission or the door or gate. The motor moves the barrier at maximum speed for the largest portion of its travel, after which the operator slowly decreases speed from 100 percent to 20 percent as the barrier approaches the limit of travel, providing a soft, smooth and quiet stop. A slow, smooth start and stop provides a safer barrier movement operator for the user because there is less momentum to apply an impulse force in the event of an obstruction. In a fast system, relatively high momentum of the door changes to zero at the obstruction before the system can actually detect the obstruction. This leads to the application of a high impulse force. With the system of the invention, a slower stop speed means the system has less momentum to overcome, and therefore a softer, more forgiving force reversal. A slow, smooth start and stop also provide a more aesthetically pleasing effect to the user, and when coupled with a quieter DC motor, a barrier movement operator which operates very quietly.
The operator includes two relays and a pair of field effect transistors (FETs) for controlling the motor. The relays are used to control direction of travel. The FET's, with phase controlled pulse width modulation, control start up and speed. Speed is responsive to the duration of the pulses applied to the FETs. A longer pulse causes the FETs to be on longer causing the barrier speed to increase. Shorter pulses result in a slower speed. This provides a very fine ramp control and more gentle starts and stops.
The movable barrier operator provides for the automatic measurement and calculation of the total distance the door is to travel. The total door travel distance is the distance between the UP and the DOWN limits (which depend on the type of door). The automatic measurement of door travel distance is a measure of the length of the door. Since shorter doors must travel at slower speeds than normal doors (for safety reasons), this enables the operator to automatically adjust the motor speed so the speed of door travel is the same regardless of door size. The total door travel distance in turn determines the maximum speed at which the operator will travel. By determining the total distance traveled, travel speeds can be automatically changed without having to modify the hardware.
The movable barrier operator provides full door or gate closure, i.e. a firm closure of the door to the floor so that the door is not movable in place after it stops. The operator includes a digital controller or processor, specifically a microcontroller which has an internal microprocessor, an internal RAM and an internal ROM and an external EEPROM. The microcontroller executes instructions stored in its internal ROM and provides motor direction control signals to the relays and speed control signals to the FETs. The operator is first operated in a learn mode to store a DOWN limit position for the door. The DOWN limit position of the door is used as an approximation of the location of the floor (or as a minimum reversal point, below which no auto-reverse will occur). When the door reaches the DOWN limit position, the microcontroller causes the electric motor to drive the door past the DOWN limit a small distance, say for one or two inches. This causes the door to close solidly on the floor.
The operator embodying the present invention provides variable door or gate output speed, i.e., the user can vary the minimum speed at which the motor starts and stops the door. This enables the user to overcome differences in door installations, i.e. stickiness and resistance to movement and other varying functional-type forces. The minimum barrier speeds in the UP and DOWN directions are determined by the user-configured force settings, which are adjusted using UP and DOWN force potentiometers. The force potentiometers set the lengths of the pulses to the FETs, which translate to variable speeds. The user gains a greater force output and a higher minimum starting speed to overcome differences in door installations, i.e. stickiness and resistance to movement and other varying functional-type forces speed, without affecting the maximum speed of travel for the door. The user can configure the door to start at a speed greater than a default value, say 20 percent. This greater start up and slow down speed is transferred to the linearly variable speed function in that instead of traveling at 20 percent speed, increasing to 100 percent speed, then decreasing to 20 percent speed, the door may, for instance, travel at 40 percent speed to 100 percent speed and back down to 40 percent speed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a garage having mounted within it a garage door operator embodying the present invention;
FIG. 2 is an exploded perspective view of a head unit of the garage door operator shown in FIG. 1;
FIG. 3 is an exploded perspective view of a portion of a transmission unit of the garage door operator shown in FIG. 1;
FIG. 4 is a block diagram of a controller and motor mounted within the head unit of the garage door operator shown in FIG. 1;
FIGS. 5 A- 5 D are a schematic diagram of the controller shown in block format in FIG. 4;
FIGS. 6 A- 6 B are a flow chart of an overall routine that executes in a microprocessor of the controller shown in FIGS. 5 A- 5 D;
FIGS. 7 A- 7 H are a flow chart of the main routine executed in the microprocessor;
FIG. 8 is a flow chart of a set variable light shut-off timer routine executed by the microprocessor;
FIGS. 9 A- 9 C are a flow chart of a hardware timer interrupt routine executed in the microprocessor;
FIGS. 10 A- 10 C are a flow chart of a 1 millisecond timer routine executed in the microprocessor;
FIGS. 11 A- 11 C are a flow chart of a 125 millisecond timer routine executed in the microprocessor;
FIGS. 12 A- 12 B are a flow chart of a 4 millisecond timer routine executed in the microprocessor;
FIGS. 13 A- 13 B are a flow chart of an RPM interrupt routine executed in the microprocessor;
FIG. 14 is a flow chart of a motor state machine routine executed in the microprocessor;
FIG. 15 is a flow chart of a stop in midtravel routine executed in the microprocessor;
FIG. 16 is a flow chart of a DOWN position routine executed in the microprocessor;
FIGS. 17 A- 17 C are a flow chart of an UP direction routine executed in the microprocessor;
FIG. 18 is a flow chart of an auto-reverse routine executed in the microprocessor;
FIG. 19 is a flow chart of an UP position routine executed in the microprocessor;
FIGS. 20 A- 20 D are a flow chart of the DOWN direction routine executed in the microprocessor;
FIG. 21 is an exploded perspective view of a pass point detector and motor of the operator shown in FIG. 2;
FIG. 22A is a plan view of the pass point detector shown in FIG. 21; and
FIG. 22B is a partial plan view of the pass point detector shown in FIG. 21 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and especially to FIG. 1, a movable barrier or garage door operator system is generally shown therein and referred to by numeral 8 . The system 8 includes a movable barrier operator or garage door operator 10 having a head unit 12 mounted within a garage 14 . More specifically, the head unit 12 is mounted to a ceiling 15 of the garage 14 . The operator 10 includes a transmission 18 extending from the head unit 12 with a releasable trolley 20 attached. The releasable trolley 20 releasably connects an arm 22 extending to a single panel garage door 24 positioned for movement along a pair of door rails 26 and 28 .
The system 8 includes a hand-held RF transmitter unit 30 adapted to send signals to an antenna 32 (see FIG. 4) positioned on the head unit 12 and coupled to a receiver within the head unit 12 as will appear hereinafter. A switch module 39 is mounted on the head unit 12 . Switch module 39 includes switches for each of the commands available from a remote transmitter or from an optional wall-mounted switch (not shown). Switch module 39 enables an installer to conveniently request the various learn modes during installation of the head unit 12 . The switch module 39 includes a learn switch, a light switch, a lock switch and a command switch, which are described below. Switch module 39 may also include terminals for wiring a pedestrian door state sensor comprising a pair of contacts 13 and 15 for a pedestrian door 11 , as well as wiring for an optional wall switch (not shown).
The garage door 24 includes the pedestrian door 11 . Contact 13 is mounted to door 24 for contact with contact 15 mounted to pedestrian door 11 . Both contacts 13 and 15 are connected via a wire 17 to head unit 12 . As will be described further below, when the pedestrian door 11 is closed, electrical contact is made between the contacts 13 and 15 closing a pedestrian door circuit in the receiver in head unit 12 and signalling that the pedestriam door state is closed. This circuit must be closed before the receiver will permit other portions of the operator to move the door 24 . If circuit is open, indicating that the pedestrian door state is open, the system will not permit door 24 to move.
The head unit 12 includes a housing comprising four sections: a bottom section 102 , a front section 106 , a back section 108 and a top section 110 , which are held together by screws 112 as shown in FIG. 2 . Cover 104 fits into front section 106 and provides a cover for a worklight. External AC power is supplied to the operator 10 through a power cord 122 . The AC power is applied to a step-down transformer 120 . An electric motor 118 is selectively energized by rectified AC power and drives a sprocket 125 in sprocket assembly 124 . The sprocket 125 drives chain 144 (see FIG. 3 ). A printed circuit board 114 includes a controller 200 and other electronics for operating the head unit 12 . A cable 116 provides input and output connections on signal paths between the printed circuit board 114 and switch module 39 . The transmission 18 , as shown in FIG. 3, includes a rail 142 which holds chain 144 within a rail and chain housing 140 and holds the chain in tension to transfer mechanical energy from the motor to the door.
A block diagram of the controller and motor connections is shown in FIG. 4 . Controller 200 includes an RF receiver 80 , a microprocessor 300 and an EEPROM 302 . RF receiver 80 of controller 200 receives a command to move the door and actuate the motor either from remote transmitter 30 , which transmits an RF signal which is received by antenna 32 , or from a user command switch 250 . User command switch 250 can be a switch on switch panel 39 , mounted on the head unit, or a switch from an optional wall switch. Upon receipt of a door movement command signal from either antenna 32 or user switch 250 , the controller 200 sends a power enable signal via line 240 to AC hot connection 206 which provides AC line current to transformer 212 and power to work light 210 . Rectified AC is provided from rectifier 214 via line 236 to relays 232 and 234 . Depending on the commanded direction of travel, controller 200 provides a signal to either relay 232 or relay 234 . Relays 232 and 234 are used to control the direction of rotation of motor 118 by controlling the direction of current flow through the windings. One relay is used for clockwise rotation; the other is used for counterclockwise rotation.
Upon receipt of the door movement command signal, controller 200 sends a signal via line 230 to power-control FET 252 . Motor speed is determined by the duration or length of the pulses in the signal to a gate electrode of FET 252 . The shorter the pulses, the slower the speed. This completes the circuit between relay 232 and FET 252 providing power to motor 118 via line 254 . If the door had been commanded to move in the opposite direction, relay 234 would have been enabled, completing the circuit with FET 252 and providing power to motor 118 via line 238 .
With power provided, the motor 118 drives the output shaft 216 which provides drive power to transmission sprocket 125 . Gear reduction housing 260 includes an internal pass point system which sends a pass point signal via line 220 to controller 200 whenever the pass point is reached. The pass point signal is provided to controller 200 via current limiting resistor 226 to protect controller 200 from electrostatic discharge (ESD). An RPM interrupt signal is provided via line 224 , via current limiting resistor 228 , to controller 200 . Lead 222 provides a plus five volts supply for the Hall effect sensors in the RPM module. Commanded force is input by two force potentiometers 202 , 204 . Force potentiometer 202 is used to set the commanded force for UP travel; force potentiometer 204 is used to set the commanded force for DOWN travel. Force potentiometers 202 and 204 provide commanded inputs to controller 200 which are used to adjust the length of the pulsed signal provided to FET 252 .
The pass point for this system is provided internally in the motor 118 . Referring to FIG. 21, the pass point module 40 is attached to gear reduction housing 260 of motor 118 . Pass point module 40 includes upper plate 42 which covers the three internal gears and switch within lower housing 50 . Lower housing 50 includes recess 62 having two pins 61 which position switch assembly 52 in recess 62 . Housing 50 also includes three cutouts which are sized to support and provide for rotation of the three geared elements. Outer gear 44 fits rotatably within cutout 64 . Outer gear 44 includes a smooth outer surface for rotating within housing 50 and inner gear teeth for rotating middle gear 46 . Middle gear 46 fits rotatably within inner cutout 66 . Middle gear 46 includes a smooth outer surface and a raised portion with gear teeth for being driven by the gear teeth of outer ring gear 44 . Inner gear 48 fits within middle gear 46 and is driven by an extension of shaft 216 (FIG. 4 ). Rotation of the motor 118 causes shaft 216 to rotate and drive inner gear 48 .
Outer gear 44 includes a notch 74 in the outer periphery. Middle gear includes a notch 76 in the outer periphery. Referring to FIG. 22A, rotation of inner gear 48 rotates middle gear 46 in the same direction. Rotation of middle gear 46 rotates outer gear 44 in the same direction. Gears 46 and 44 are sized such that pass point indications comprising switch release cutouts 74 and 76 line up only once during the entire travel distance of the door. As seen in FIG. 22A, when switch release cutouts 74 and 76 line up, switch 72 is open generating a pass point presence signal. The location where switch release cutouts 74 and 76 line up is the pass point. At all other times, at least one of the two gears holds switch 72 closed generating a signal indicating that the pass point has not been reached.
The receiver portion 80 of controller 200 is shown in FIG. 5 A. RF signals may be received by the controller 200 at the antenna 32 and fed to the receiver 80 . The receiver 80 includes variable inductor L 1 and a pair of capacitors C 2 and C 3 that provide impedance matching between the antenna 32 and other portions of the receiver. An NPN transistor Q 4 is connected in common-base configuration as a buffer amplifier. Bias to the buffer amplifier transistor Q 4 is provided by resistors R 2 , R 3 . The buffered RF output signal is supplied to a second NPN transistor Q 5 . The radio frequency signal is coupled to a bandpass amplifier 280 to an average detector 282 which feeds a comparator 284 . Referring to FIGS. 5C and 5B, the analog output signal A, B is applied to noise reduction capacitors C 19 , C 20 and C 21 then provided to pins P 32 and P 33 of the microcontroller 300 . Microcontroller 300 may be a Z86733 microprocessor.
As can be seen in FIG. 5D, an external transformer 212 receives AC power from a source such as a utility and steps down the AC voltage to the power supply 90 circuit of controller 200 . Transformer 212 provides AC current to full-wave bridge circuit 214 , which produces a 28 volt full wave rectified signal across capacitor C 35 . The AC power may have a frequency of 50 Hz or 60 Hz. An external transformer is especially important when motor 118 is a DC motor. The 28 volt rectified signal is used to drive a wall control switch, an obstacle detector circuit, a door-in-door switch and to power FETs Q 11 and Q 12 (FIG. 5C) used to start the motor. Zener diode D 18 protects against overvoltage due to the pulsed current, in particular, from the FETs rapidly switching off inductive load of the motor. The potential of the full-wave rectified signal is further reduced to provide 5 volts at capacitor C 38 , which is used to power the microprocessor 300 , the receiver circuit 80 and other logic functions.
The 28 volt rectified power supply signal indicated by reference numeral T in FIG. 5C is voltage divided down by resistors R 61 and R 62 , then applied to an input pin P 24 of microprocessor 300 (FIG. 5 B). This signal is used to provide the phase of the power line current to microprocessor 300 . Microprocessor 300 constantly checks for the phase of the line voltage in order to determine if the frequency of the line voltage is 50 Hz or 60 Hz. This information is used to establish the worklight time-out period and to select the look-up table stored in the ROM in the microcontroller for converting pulse width to door speed.
When the door is commanded to move, either through a signal from a remote transmitter received through antenna 32 and processed by receiver 80 , or through an optional wall switch, the microprocessor 300 commands the work light to turn on. Microprocessor 300 (FIG. 5B) sends a worklight enable signal from pin P 07 . In FIG. 5C, the worklight enable signal is applied to the base of transistor Q 3 , which drives relay K 3 . AC power from a signal U provides power for operating the worklight 210 .
Microprocessor 300 reads from and writes data to an EEPROM 302 via its pins P 25 , P 26 and P 27 . EEPROM 302 may be a 93C46. Microprocessor 300 provides a light enable signal at pin P 21 which is used to enable a learn mode indicator yellow LED D 15 . LED D 15 is enables or lit when the receiver is in the learn mode. Pin P 26 provides double duty. When the user selects switch S 1 , a learn enable signal is provided to both microprocessor 300 and EEPROM 302 . Switch S 1 is mounted on the head unit 12 and is part of switch module 39 , which is used by the installer to operate the system.
An optional flasher module provides an additional level of safety for users and is controlled by microprocessor 300 at pin P 22 . The optional flasher module is connected between terminals 308 and 310 . In the optional flasher module, after receipt of a door command, the microprocessor 300 sends a signal from P 22 which causes the flasher light to blink for 2 seconds. The door does not move during that 2 second period, giving the user notice that the door has been commanded to move and will start to move in 2 seconds. After expiration of the 2 second period, the door moves and the flasher light module blinks during the entire period of door movement. If the operator does not have a flasher module installed in the head unit, when the door is commanded to move, there is no time delay before the door begins to move.
Microprocessor 300 provides the signals which start motor 118 , control its direction of rotation (and thus the direction of movement of the door) and the speed of rotation (speed of door travel). FETs Q 11 and Q 12 are used to start motor 118 . Microprocessor 300 applies a pulsed output signal to the gates of FETs Q 11 and Q 12 . The lengths of the pulses determine the time the FETs conduct and thus the amount of time current is applied to start and run the motor 118 . The longer the pulse, the longer current is applied, the greater the speed of rotation the motor 118 will develop. Diode D 11 is coupled between the 28 volt power supply and is used to clean up flyback voltage to the input bridge D 4 when the FETs are conducting. Similarly, Zener diode D 19 (see FIG. 5D) is used to protect against overvoltage when the FETs are conducting.
Control of the direction of rotation of motor 118 (and thus direction of travel of the door) is accomplished with two relays, K 1 and K 2 (FIG. 5 C). Relay K 1 supplies current to cause the motor to rotate clockwise in an opening direction (door moves UP); relay K 2 supplies current to cause the motor to rotate counterclockwise in a closing direction (door moves DOWN). When the door is commanded to move UP, the microprocessor 300 sends an enable signal from pin P 05 to the base of transistor Q 1 , which drives relay K 1 . When the door is commanded to move DOWN, the microprocessor 300 sends an enable signal from pin P 06 to the base of transistor Q 2 , which drives relay K 2 .
Door-in-door contacts 13 and 15 are connected to terminals 304 and 306 . Terminals 304 and 306 are connected to relays K 1 and K 2 . If the signal between contacts 13 and 15 is broken, the signal across terminals 304 and 306 is open, preventing relays K 1 and K 2 from energizing. The motor 118 will not rotate and the door 24 will not move until the user closes pedestrian door 11 , making contact between contacts 13 and 15 .
In FIG. 5B, the pass point signal 220 from the pass point module 40 (see FIG. 21) of motor 118 is applied to pin P 23 of microprocessor 300 . The RPM signal 224 from the RPM sensor module in motor 118 is applied to pin P 31 of microprocessor 300 . Application of the pass point signal and the RPM signal is described with reference to the flow charts.
An optional wall control, which duplicates the switches on remote transmitter 30 , may be connected to controller 200 at terminals 312 and 314 . When the user presses the door command switch 39 , a dead short is made to ground, which the microprocessor 300 detects by the failure to detect voltage. Capacitor C 22 is provided for RF noise reduction. The dead short to ground is sensed at pins P 02 and P 03 , for redundancy.
Switches S 1 and S 2 are part of switch module 39 mounted on head unit 12 and used by the installer for operating the system. As stated above, S 1 is the learn switch. S 2 is the door command switch. When S 2 is pressed, microprocessor 300 detects the dead short at pins P 02 and P 03 .
Input from an obstacle detector (not shown) is provided at terminal 316 . This signal is voltage divided down and provided to microprocessor 300 at pins P 20 and P 30 , for redundancy. Except when the door is moving and less than an inch above the floor, when the obstacle detector senses an object in the doorway, the microprocessor executes the auto-reverse routine causing the door to stop and/or reverse depending on the state of the door movement.
Force and speed of door travel are determined by two potentiometers. Potentiometer R 33 adjusts the force and speed of UP travel; potentiometer R 34 adjusts the force and speed of DOWN travel. Potentiometers R 33 and R 34 act as analog voltage dividers. The analog signal from R 33 , R 34 is further divided down by voltage divider R 35 /R 37 , R 36 /R 38 before it is applied to the input of comparators 320 and 322 . Reference pulses from pins P 34 and P 35 of microprocessor 300 are compared with the force input from potentiometers R 33 and R 34 in comparators 320 and 322 . The output of comparators 320 and 322 is applied to pins P 01 and P 00 .
To perform the A/D conversion, the microprocessor 300 samples the output of the comparators 320 and 322 at pins P 00 and P 01 to determine which voltage is higher: the voltage from the potentiometer R 33 or R 34 (IN) or the voltage from the reference pin P 34 or P 35 (REF). If the potentiometer voltage is higher than the reference, then the microprocessor outputs a pulse. If not, the output voltage is held low. The RC filter (R 39 , C 29 /R 40 , C 30 ) converts the pulses into a DC voltage equivalent to the duty cycle of the pulses. By outputting the pulses in the manner described above, the microprocessor creates a voltage at REF which dithers around the voltage at IN. The microprocessor then calculates the duty cycle of the pulse output which directly correlates to the voltage seen at IN.
When power is applied to the head unit 12 including controller 200 , microprocessor 300 executes a series of routines. With power applied, microprocessor 300 executes the main routines shown in FIGS. 6A and 6B. The main loop 400 includes three basic functions, which are looped continuously until power is removed. In block 402 the microprocessor 300 handles all non-radio EEPROM communications and disables radio access to the EEPROM 302 when communicating. This ensures that during normal operation, i.e., when the garage door operator is not being programmed, the remote transmitter does not have access to the EEPROM, where transmitter codes are stored. Radio transmissions are processed upon receipt of a radio interrupt (see below).
In block 404 , microprocessor 300 maintains all low priority tasks, such as calculating new force levels and minimum speed. Preferably, a set of redundant RAM registers is provided. In the event of an unforeseen event (e.g., and ESD event) which corrupts regular RAM, the main RAM registers and the redundant RAM registers will not match. Thus, when the values in RAM do not match, the routine knows the regular RAM has been corrupted. (See block 504 below.) In block 406 , microprocessor 300 tests redundant RAM registers. Several interrupt routines can take priority over blocks 402 , 404 and 406 .
The infrared obstacle detector generates an asynchronous IR interrupt signal which is a series of pulses. The absence of the obstacle detector pulses indicates an obstruction in the beam. After processing the IR interrupt, microprocessor 300 sets the status of the obstacle detector as unobstructed at block 416 .
Receipt of a transmission from remote transmitter 30 generates an asynchronous radio interrupt at block 410 . At block 418 , if in the door command mode, microprocessor 300 parses incoming radio signals and sets a flag if the signal matches a stored code. If in the learn mode, microprocessor 300 stores the new transmitter codes in the EEPROM.
An asynchronous interrupt is generated if a remote communications unit is connected to an optional RS-232 communications port located on the head unit. Upon receipt of the hardware interrupt, microprocessor 300 executes a serial data communications routine for transferring and storing data from the remote hardware.
Hardware timer 0 interrupt is shown in block 422 . In block 424 , microprocessor 300 reads the incoming AC line signal from pin P 24 and handles the motor phase control output. The incoming line signal is used to determine if the line voltage is 50 Hz for the foreign market or 60 Hz for the domestic market. With each interrupt, microprocessor 300 , at block 426 , task switches among three tasks. In block 428 , microprocessor 300 updates software timers. In block 430 , microprocessor 300 debounces wall control switch signals. In block 432 , microprocessor 300 controls the motor state, including motor direction relay outputs and motor safety systems.
When the motor 118 is running, it generates an asynchronous RPM interrupt at block 434 . When microprocessor 300 receives the asynchronous RPM interrupt at pin P 31 , it calculates the motor RPM period at block 436 , then updates the position of the door at block 438 .
Further details of main loop 400 are shown in FIGS. 7A through 7H. The first step executed in main loop 400 is block 450 , where the microprocessor checks to see if the pass point has been passed since the last update. If it has, the routine branches to block 452 , where the microprocessor 300 updates the position of the door relative to the pass point in EEPROM 302 or non-volatile memory. The routine then continues at block 454 . An optional safety feature of the garage door operator system enables the worklight, when the door is open and stopped and the infrared beam in the obstacle detector is broken.
At block 454 , the microprocessor checks if the enable/disable of the worklight for this feature has been changed. Some users want the added safety feature; others prefer to save the electricity used. If new input has been provided, the routine branches to block 456 and sets the status of the obstacle detector-controlled worklight in non-volatile memory in accordance with the new input. Then the routine continues to block 458 where the routine checks to determine if the worklight has been turned on without the timer. A separate switch is provided on both the remote transmitter 30 and the head unit at module 39 to enable the user to switch on the worklight without operating the door command switch. If no, the routine skips to block 470 .
If yes, the routine checks at block 460 to see if the one-shot flag has been set for an obstacle detector beam break. If no, the routine skips to block 470 . If yes, the routine checks if the obstacle detector controlled worklight is enabled at block 462 . If not, the routine skips to block 470 . If it is, the routine checks if the door is stopped in the fully open position at block 464 . If no, the routine skips to block 470 . If yes, the routine calls the SetVarLight subroutine (see FIG. 8) to enable the appropriate turn off time (4.5 minutes for 60 Hz systems or 2.5 minutes for 50 Hz systems). At block 468 , the routine turns on the worklight.
At block 470 , the microprocessor 300 clears the one-shot flag for the infrared beam break. This resets the obstacle detector, so that a later beam break can generate an interrupt. At block 472 , if the user has installed a temporary password usable for a fixed period of time, the microprocessor 300 updates the non-volatile timer for the radio temporary password. At block 474 , the microprocessor 300 refreshes the RAM registers for radio mode from non-volatile memory (EEPROM 302 ). At block 476 , the microprocessor 300 refreshes I/O port directions, i.e., whether each of the ports is to be input or output. At block 478 , the microprocessor 300 updates the status of the radio lockout flag, if necessary. The radio lockout flag prevents the microprocessor from responding to a signal from a remote transmitter. A radio interrupt (described below) will disable the radio lockout flag and enable the remote transmitter to communicate with the receiver.
At block 480 , the microprocessor 300 checks if the door is about to travel. If not, the routine skips to block 502 . If the door is about to travel, the microprocessor 300 checks if the limits are being trained at block 482 . If they are, the routine skips to block 490 . If not, the routine asks at block 484 if travel is UP or DOWN. If DOWN, the routine refreshes the DOWN limit from non-volatile memory (EEPROM 302 ) at block 486 . If UP, the routine refreshes the UP limit from non-volatile memory (EEPROM 302 ) at block 488 . The routine updates the current operating state and position relative to the pass point in non-volatile memory at block 490 . This is a redundant read for stability of the system.
At block 492 , the routine checks for completion of a limit training cycle. If training is complete, the routine branches to block 494 where the new limit settings and position relative to the pass point are written to non-volatile memory.
The routine then updates the counter for the number of operating cycles at block 496 . This information can be downloaded at a later time and used to determine when certain parts need to be replaced. At block 498 the routine checks if the number of cycles is a multiple of 256 . Limiting the storage of this information to multiples of 256 limits the number of times the system has to write to that register. If yes it updates the history of force settings at clock 500 . If not, the routine continues to block 502 .
At block 502 the routine updates the learn switch debouncer. At block 504 the routine performs a continuity check by comparing the backup (redundant) RAM registers with the main registers. If they do not match, the routine branches to block 506 . If the registers do not match, the RAM memory has been corrupted and the system is not safe to operate, so a reset is commanded. At this point, the system powers up as if power had been removed and reapplied and the first step is a self test of the system (all installation settings are unchanged).
If the answer to block 504 is yes, the routine continues to block 508 where the routine services any incoming serial messages from the optional wall control (serial messages might be user input start or stop commands). The routine then loads the UP force timing from the ROM look-up table, using the user setting as an index at block 510 . Force potentiometers R 33 and R 34 are set by the user. The analog values set by the user are converted to digital values. The digital values are used as an index to the look-up table stored in memory. The value indexed from the look-up table is then used as the minimum motor speed measurement. When the motor runs, the routine compares the selected value from the look-up table with the digital timing from the RPM routine to ensure the force is acceptable.
Instead of calculating the force each time the force potentiometers are set, a look-up table is provided for each potentiometer. The range of values based on the range of user inputs is stored in ROM and used to save microprocessor processing time. The system includes two force limits: one for the UP force and one for the DOWN force. Two force limits provide a safer system. A heavy door may require more UP force to lift, but need a lower DOWN force setting (and therefore a slower closing speed) to provide a soft closure. A light door will need less UP force to open the door and possibly a greater DOWN force to provide a full closure.
Next the force timing is divided by power level of the motor for the door to scale the maximum force timeout at block 512 . This step scales the force reversal point based on the maximum force for the door. The maximum force for the door is determined based on the size of the door, i.e. the distance the door travels. Single piece doors travel a greater distance than segmented doors. Short doors require less force to move than normal doors. The maximum force for a short door is scaled down to 60 percent of the maximum force available for a normal door. So, at block 512 , if the force setting is set by the user, for example at 40 percent, and the door is a normal door (i.e., a segmented door or multi-paneled door), the force is scaled to 40 percent of 100 percent. If the door is a short door (i.e., a single panel door), the force is scaled to 40 percent of 60 percent, or 24 percent.
At block 514 , the routine loads the DOWN force timing from the ROM look-up table, using the user setting as an index. At block 516 , the routine divides the force timing by the power level of the motor for the door to scale the force to the speed.
At block 518 the routine checks if the door is traveling DOWN. If yes, the routine disables use of the MinSpeed Register at block 524 and loads the MinSpeed Register with the DOWN force setting, i.e., the value read from the DOWN force potentiometer at block 526 . If not, the routine disables use of the MinSpeed Register at block 520 and loads the MinSpeed Register with the UP force setting from the force potentiometer at block 522 .
The routine continues at block 528 where the routine subtracts 24 from the MinSpeed value. The MinSpeed value ranges from 0 to 63. The system uses 64 levels of force. If the result if negative at block 530 , the routine clears the MinSpeed Register at block 532 to effectively truncate the lower 38 percent of the force settings. If no, the routine divides the minimum speed by 4 to scale 8 speeds to 32 force settings at block 534 . At block 536 , the routine adds 4 into the minimum speed to correct the offset, and clips the result to a maximum of 12. At block 538 the routine enables use of the MinSpeed Register.
At block 540 the routine checks if the period of the rectified AC line signal (input to microprocessor 300 at pin P 24 ) is less than 9 milliseconds (indicating the line frequency is 60 Hz). If it is, the routine skips to block 548 . If not, the routine checks if the light shut-off timer is active at block 542 . If not, the routine skips to block 548 . If yes, the routine checks if the light time value is greater than 2.5 minutes at block 544 . If no, the routine skips to block 548 . If yes, the routine calls the SetVarLight subroutine (see FIG. 8 ), to correct the light timing setting, at block 546 .
At block 548 the routine checks if the radio signal has been clear for 100 milliseconds or more. If not, the routine skips to block 552 . If yes, the routine clears the radio at block 550 . At block 552 , the routine resets the watchdog timer. At block 554 , the routine loops to the beginning of the main loop.
The SetVarLight subroutine, FIG. 8, is called whenever the door is commanded to move and the worklight is to be turned on. When the SetVarLight subroutine, block 558 is called, the subroutine checks if the period of the rectified power line signal (pin P 24 of microprocessor 300 ) is greater than or equal to 9 milliseconds. If yes, the line frequency is 50 Hz, and the timer is set to 2.5 minutes at block 564 . If no, the line frequency is 60 Hz and the timer is set to 4.5 minutes at block 562 . After setting, the subroutine returns to the call point at block 566 .
The hardware timer interrupt subroutine operated by microprocessor 300 , shown at block 422 , runs every 0.256 milliseconds. Referring to FIGS. 9 A- 9 C, when the subroutine is first called, it sets the radio interrupt status as indicated by the software flags at clock 580 . At block 582 , the subroutine updates the software timer extension. The next series of steps monitor the AC power line frequency (pin P 24 of microprocessor 300 ). At step 584 , the subroutine checks if the rectified power line input is high (checks for a leading edge). If yes, the subroutine skips to block 594 , where it increments the power line high time counter, then continues to block 596 . If no, the subroutine checks if the high time counter is below 2 milliseconds at block 586 . If yes, the subroutine skips to block 594 . If no, the subroutine sets the measured power line time in RAM at block 588 . The subroutine then resets the power line high time counter at block 590 and resets the phase timer register in block 592 .
At block 596 , the subroutine checks if the motor power level is set at 100 percent. If yes, the subroutine turns on the motor phase control output at block 606 . If no, the subroutine checks if the motor power level is set at 0 percent at block 598 . If yes, the subroutine turns off the motor phase control output at block 604 . If no, the phase timer register is decremented at block 600 and the result is checked for sign at block 602 . If positive the subroutine branches to block 606 ; if negative the subroutine branches to block 604 .
The subroutine continues at block 608 where the incoming RPM signal (at pin P 31 of microprocessor 300 ) is digitally filtered. Then the time prescaling task switcher (which loops through 8 tasks identified at blocks 620 , 630 , 640 , 650 ) is incremented at block 610 . The task switcher varies from 0 to 7. At block 612 , the subroutine branches to the proper task depending on the value of the task switcher.
If the task switcher is at value 2 (this occurs every 4 milliseconds), the execute motor state machine subroutine is called at block 620 . If the task is value 0 or 4 (this occurs every 2 milliseconds), the wall control switches are debounced at block 630 . If the task value is 6 (this occurs every 4 milliseconds), the execute 4 ms timer subroutine is called at block 640 . If the task is value 1, 3, 5 or 7, the 1 millisecond timer subroutine is called at block 650 . Upon completion of the called subroutine, the 0.256 millisecond timer subroutine returns at block 614 .
Details of the 1 ms timer subroutine (block 650 ) are shown in FIGS. 10 A- 10 C. When this subroutine is called, the first step is to update the A/D converters on the UP and DOWN force setting potentiometers (P 34 and P 35 of microprocessor 300 ) at block 652 . At block 654 , the subroutine checks if the A/D conversion (comparison at comparators 320 and 322 ) is complete. If yes, the measured potentiometer values are stored at block 656 . Then the stored values (which vary from 0 to 127) are divided by 2 to obtain the 64 level force setting at block 658 . If no, the subroutine decrements the infrared obstacle detector timeout timer at block 660 . In block 662 , the subroutine checks if the timer has reached zero. If no, the subroutine skips to block 672 . If yes, the subroutine resets the infrared obstacle detector timeout timer at block 664 . The flag setting for the obstacle detector signal is checks at block 666 . If no, the one-shot break flag is set at block 668 . If yes, the flag is set indicating the obstacle detector signal is absent at block 670 .
At block 672 , the subroutine increments the radio time out register. Then the infrared obstacle detector reversal timer is decremented at block 674 . The pass point input is debounced at block 676 . The 125 millisecond prescaler is incremented at block 678 . Then the prescaler is checked to see if it has reached 63 milliseconds at block 680 . If yes, the fault blinking LED is updated at block 682 . If no, the prescaler is checked if it has reached 125 ms at block 684 . If yes, the 125 ms timer subroutine is executed at block 686 . If no, the routine returns at block 688 .
Turning to FIGS. 11 A-C, the 125 millisecond timer subroutine (block 690 ) is used to manage the power level of the motor 118 . At block 692 , the subroutine updates the RS-232 mode timer and exits the RS-232 mode timer if necessary. The same pair of wires is used for both wall control switches and RS-232 communication. If RS-232 communication is received while in the wall control mode, the RS-232 mode is entered. If four seconds passes since the last RS-232 word was received, then the RS-232 timer times out and reverts to the wall control mode. At block 694 the subroutine checks if the motor is set to be stopped. If yes, the subroutine skips to block 716 and sets the motor's power level to 0 percent. If no, the subroutine checks if the pre-travel safety light is flashing at block 696 (if the optional flasher module has been installed, a light will flash for 2 seconds before the motor is permitted to travel and then flash at a predetermined interval during motor travel). If yes, the subroutine skips to block 716 and sets the motor's power level to 0 percent.
If no, the subroutine checks if the microprocessor 300 is in the last phase of a limit training mode at block 698 . If yes, the subroutine skips to block 710 . If no, the subroutine checks if the microprocessor 300 is in another part of the limit training mode at block 700 . If no, the subroutine skips to block 710 . If yes, the subroutine sets the motor ramp-up complete flag in step 702 and checks if the minimum speed (as determined by the force settings) is greater than 40 percent at block 704 . If no, the power level is set to 40 percent at block 708 . If yes, the power level is set equal to the minimum speed stored in MinSpeed Register at block 706 .
At block 710 the subroutine checks if the flag is set to slow down. If yes, the subroutine checks if the motor is running above or below minimum speed at block 714 . If above minimum speed, the power level of the motor is decremented one step increment (one step increment is preferably 5% of maximum motor speed) at block 722 . If below the minimum speed, the power level of the motor is incremented one step increment (which is preferably 5% of maximum motor speed) to minimum speed at block 720 .
If the flag is not set to slow down at block 710 , the subroutine checks if the motor is running at maximum allowable speed at block 712 . If no, the power level of the motor is incremented one step increment (which is preferably 5% of maximum motor speed) at block 720 . If yes, the flag is set for motor ramp-up speed complete.
The subroutine continues at block 724 where it checks if the period of the rectified AC power line (pin P 24 of microprocessor 300 ) is greater than or equal to 9 ms. If no, the subroutine fetches the motor's phase control information (indexed from the power level) from the 60 Hz look-up table stored in ROM at block 728 . If yes, the subroutine fetches the motor's phase control information (indexed from the power level) from the 50 Hz look-up table stored in ROM at block 726 .
The subroutine tests for a user enable/disable of the infrared obstacle detector-controlled worklight feature at block 730 . Then the user radio learning timers, ZZWIN (at the wall keypad if installed) and AUXLEARNSW (radio on air and worklight command) are updated at block 732 . The software watchdog timer is updated at block 734 and the fault blinking LED is updated at block 736 . The subroutine returns at block 738 .
The 4 millisecond timer subroutine is used to check on various systems which do not require updating as often as more critical systems. Referring to FIGS. 12A and 12B, the subroutine is called at block 640 . At block 750 , the RPM safety timers are updated. These timers are used to determine if the door has engaged the floor. The RPM safety timer is a one second delay before the operator begins to look for a falling door, i.e., one second after stopping. There are two different forces used in the garage door operator. The first type force are the forces determined by the UP and DOWN force potentiometers. These force levels determine the speed at which the door travels in the UP and DOWN directions. The second type of force is determined by the decrease in motor speed due to an external force being applied to the door (an obstacle or the floor). This programmed or pre-selected external force is the maximum force that the system will accept before an auto-reverse or stop is commanded.
At block 752 the 0.5 second RPM timer is checked to se if it has expired. If yes, the 0.5 second timer is reset at block 754 . At block 756 safety checks are performed on the RPM sen during the last 0.5 seconds to prevent the door from falling. The 0.5 second timer is chosen so the maximum force achieved at the trolley will reach 50 kilograms in 0.5 seconds if the motor is operating at 100 percent of power.
At block 758 , the subroutine updates the 1 second timer for the optional light flasher module. In this embodiment, the preferred flash period is 1 second. At block 760 the radio dead time and dropout timers are updated. At block 762 the learn switch is debounced. At block 764 the status of the worklight is updated in accordance with the various light timers. At block 766 the optional wall control blink timer is updated. The optional wall control includes a light which blinks when the door is being commanded to auto-reverse in response to an infrared obstacle detector signal break. At block 768 the subroutine returns.
Further details of the asynchronous RPM signal interrupt, block 434 , are shown in FIGS. 13A and 13B. This signal, which is provided to microprocessor 300 at pin P 31 , is used to control the motor speed and the position detector. Door position is determined by a value relative to the pass point. The pass point is set at 0. Positions above the pass point are negative; positions below the pass point are positive. When the door travels to the UP limit, the position detector (or counter) determines the position based on the number of RPM pulses to the UP limit number. When the door travels DOWN to the DOWN limit, the position detector counts the number of RPM pulses to the DOWN limit number. The UP and DOWN limit numbers are stored in a register.
At block 782 the RPM interrupt subroutine calculates the period of the incoming RPM signal. If the door is traveling UP, the subroutine calculates the difference between two successive pulses. If the door is traveling DOWN, the subroutine calculates the difference between two successive pulses. At block 784 , the subroutine divides the period by 8 to fit into a binary word. At block 786 the subroutine checks if the motor speed is ramping up. This is the max force mode. RPM timeout will vary from 10 to 500 milliseconds. Note that these times are recommended for a DC motor. If an AC motor is used, the maximum time would be scaled down to typically 24 milliseconds. A 24 millisecond period is slower than the breakdown RPM of the motor and therefore beyond the maximum possible force of most preferred motors. If yes, the RPM timeout is set at 500 milliseconds (0.5 seconds) at block 790 . If no, the subroutine sets the RPM timeout as the rounded-up value of the force setting in block 788 .
At block 792 the subroutine checks for the direction of travel. This is found in the state machine register. If the door is traveling DOWN, the position counter is incremented at block 796 and the pass point debouncer is sampled at block 800 . At block 804 , the subroutine checks for the falling edge of the pass point signal. If the falling edge is not present, the subroutine returns at block 814 . If there is a pass point falling edge, the subroutine checks for the lowest point (in cases where more than one pass point is used). If this is not the lowest pass point, the subroutine returns at block 814 . If it is the only pass point or the lowest pass point, the position counter is zeroed at block 812 and the subroutine returns at block 814 .
If the door is traveling UP, the subroutine decrements the position counter at block 794 and samples the pass point debouncer at block 798 . Then it checks for the rising edge of the pass point signal at block 802 . If there is no pass point signal rising edge, the subroutine returns at block 814 . If there is, it checks for the lowest pass point at block 806 . If no the subroutine returns at block 814 . If yes, the subroutine zeroes the position counter at block 810 and returns at block 814 .
The motor state machine subroutine, block 620 , is shown in FIG. 14 . It keeps track of the state of the motor. At block 820 , the subroutine updates the false obstacle detector signal output, which is used in systems that do not require an infrared obstacle detector. At block 822 , the subroutine checks if the software watchdog timer has reached too high a value. If yes, a system reset is commanded at block 824 . If no, at block 826 , it checks the state of the motor stored in the motor state register located in EEPROM 302 and executes the appropriate subroutine.
If the door is traveling UP, the UP direction subroutine at block 832 is executed. If the door is traveling DOWN, the DOWN direction subroutine is executed at block 828 . If the door is stopped in the middle of the travel path, the stop in midtravel subroutine is executed at block 838 . If the door is fully closed, the DOWN position subroutine is executed at block 830 . If the door is fully open, the UP position subroutine is executed at block 834 . If the door is reversing, the auto-reverse subroutine is executed at block 836 .
When the door is stopped in midtravel, the subroutine at block 838 is called, as shown in FIG. 15 . In block 840 the subroutine updates the relay safety system (ensuring that relays K 1 and K 2 are open). The subroutine checks in block 842 for a received wall command or radio command. If there is no received command, the subroutine updates the worklight status and returns at block 850 . If yes, the motor power is set to 20 percent at block 844 and the motor state is set to traveling DOWN at block 846 . The worklight status is updated and the subroutine returns at block 850 . If the door is stopped in midtravel and a door command is received, the door is set to close. The next time the system calls the motor state machine subroutine, the motor state machine will call the DOWN direction subroutine. The door must close to the DOWN limit before it can be opened to the full UP limit.
If the state machine indicates the door is in the DOWN position (i.e. the DOWN limit position), the DOWN position subroutine, block 830 , at FIG. 16 is called. When the door is in the DOWN position, the subroutine checks if a wall control or radio command has been received at block 852 . If no, the subroutine updates the light and returns at block 858 . If yes, the motor power is set to 20 percent at block 854 and the motor state register is set to show the state is traveling UP at block 856 . The subroutine then updates the light and returns at block 858 .
The UP direction subroutine, block 832 , is shown in FIGS. 17 A- 17 C. At block 860 the subroutine waits until the main loop refreshes the UP limit from EEPROM 302 . Then it checks if 40 milliseconds have passed since closing of the light relay K 3 at block 862 . If not, the subroutine returns at block 864 . If yes, the subroutine checks for flashing the warning light prior to travel at block 866 (only if the optional flasher module is installed). If the light is flashing, the status of the blinking light is updated and the subroutine returns at block 868 . If not, or the flashing is terminated, the motor UP relay is turned on at block 870 . Then the subroutine waits until 1 second has passed after the motor was turned on at block 872 . If no, the subroutine skips to block 888 . If yes, the subroutine checks for the RPM signal timeout at block 874 . If no, the subroutine checks if the motor speed is ramping up at block 876 by checking the value of the RAMPFLAG register in RAM (i.e., UP, DOWN, FULLSPEED, STOP). If yes, the subroutine skips to block 888 . If no, the subroutine checks if the measured RPM is longer than the allowable RPM period at block 878 . If no, the subroutine continues at block 888 .
If the RPM signal has timed out at block 874 or the measured time period is longer than allowable at block 878 , the subroutine branches to block 880 . At block 880 , the reason is set as force obstruction. At block 882 , if the training limits are being set, the training status is updated. At block 884 the motor power is set to zero and the state is set as stopped in midtravel. At block 886 the subroutine returns.
At block 888 the subroutine checks if the door's exact position is known. If it is not, the door's distance from the UP limit is updated in block 890 by subtracting the UP limit stored in RAM from the position of the door also stored in RAM. Then the subroutine checks at block 892 if the door is beyond its UP limit. If yes, the subroutine sets the reason as reaching the limit in block 894 . Then the subroutine checks if the limits are being trained. If yes, the limit training machine is updated at block 898 . If no, the motor's power is set as zero and the motor state is set at the UP position in block 900 . Then the subroutine returns at block 902 .
If the door is not beyond its UP limit, the subroutine checks if the door is being manually positioned in the training cycle at block 904 . If not, the door position within the slowdown distance of the limit is checked at block 906 . If yes, the motor slow down flag is set at block 910 . If the door is being positioned manually at block 904 or the door is not within the slow down distance, the subroutine skips to block 912 . At block 912 the subroutine checks if a wall control or radio command has been received. If yes, the motor power is set at zero and the state is set at stopped in midtravel at block 916 . If no, the system checks if the motor has been running for over 27 seconds at block 914 . If no, the subroutine returns at block 918 . If yes, the motor power is set at zero and the motor state is set at stopped in midtravel at block 916 . Then the subroutine returns at block 918 .
Referring to FIG. 18, the auto-reverse subroutine block 836 is described. (Force reversal is stopping the motor for 0.5 seconds, then traveling UP.) At block 920 the subroutine updates the 0.5 second reversal timer (the force reversal timer described above). Then the subroutine checks at block 922 for expiration of the force-reversal timer. If yes, the motor power is set to 20 percent at block 924 and the motor state is set to traveling UP at block 926 and the subroutine returns at block 932 . If the timer has not expired, the subroutine checks for receipt of a wall command or radio command at block 928 . If yes, the motor power is set to zero and the state is set at stopped in midtravel at block 930 , then the subroutine returns at block 932 . If no, the subroutine returns at block 932 .
The UP position routine, block 834 , is shown in FIG. 19 . Door travel limits training is started with the door in the UP position. At block 934 , the subroutine updates the relay safety system. Then the subroutine checks for receipt of a wall command or radio command at block 936 indicating an intervening user command. If yes, the motor power is set to 20 percent at block 938 and the state is set at traveling DOWN in block 940 . Then the light is updated and the subroutine returns at block 950 . If no wall command or radio command has been received, the subroutine checks for training the limits at block 942 . If no, the light is updated and the subroutine returns at block 950 . If yes, the limit training state machine is updated at block 944 . Then the subroutine checks if it is time to travel DOWN at block 946 . If no, the subroutine updates the light and returns at block 950 . If it is time to travel DOWN, the state is set at traveling DOWN at block 948 and the system returns at block 950 .
The DOWN direction subroutine, block 828 , is shown in FIGS. 20 A- 20 D. At block 952 , the subroutine waits until the main loop routine refreshes the DOWN limit from EEPROM 302 . For safety purposes, only the main loop or the remote transmitter (radio) can access data stored in or written to the EEPROM 302 . Because EEPROM communication is handled within software, it is necessary to ensure that two software routines do not try to communicate with the EEPROM at the same time (and have a data collision). Therefore, EEPROM communication is allowed only in the Main Loop and in the Radio routine, with the Main loop having a busy flag to prevent the radio from communicating with the EEPROM at the same time. At block 954 , the subroutine checks if 40 milliseconds has passed since closing of the light relay K 3 . If no, the subroutine returns at block 956 . If yes, the subroutine checks if the warning light is flashing (for 2 seconds if the optional flasher module is installed) prior to travel at block 958 . If yes, the subroutine updates the status of the flashing light and returns at block 960 . If no, or the flashing is completed, the subroutine turns on the DOWN motor relay K 2 at block 962 . At block 964 the subroutine checks if one second has passed since the motor was first turned on. The system ignores the force on the motor for the first one second. This allows the motor time to overcome the inertia of the door (and exceed the programmed force settings) without having to adjust the programmed force settings for ramp up, normal travel and slow down. Force is effectively set to maximum during ramp up to overcome sticky doors.
If the one second time has not passed, the subroutine skips to block 984 . If the one second time limit has passed, the subroutine checks for the RPM signal time out at block 966 . If no, the subroutine checks if the motor speed is currently being ramped up at block 968 (this is a maximum force condition). If yes, the routine skips to block 984 . If no, the subroutine checks if the measured RPM period is longer than the allowable RPM period. If no, the subroutine continues at block 984 .
If either the RPM signal has timed out (block 966 ) or the RPM period is longer than allowable (block 970 ), this is an indication of an obstruction or the door has reached the DOWN limit position, and the subroutine skips to block 972 . At block 972 , the subroutine checks if the door is positioned beyond the DOWN limit setting. If it is, the subroutine skips to block 990 where it checks if the motor has been powered for at least one second. This one second power period after the DOWN limit has been reached provides for the door to close fully against the floor. This is especially important when DC motors are used. The one second period overcomes the internal braking effect of the DC motor on shut-off. Auto-reverse is disabled after the position detector reaches the DOWN limit. If the door is not positioned beyond the DOWN limit setting, the subroutine sets the reason as force obstruction at block 974 , updates the training status if the operator is training limits at block 976 , and sets the motor power at 0 at block 978 . The motor state is set as autoreverse at block 980 , and the subroutine returns at block 982 .
If the subroutine determines that the door position is beyond the DOWN limit setting and if the motor as been running for one second, at block 990 , the subroutine sets the reason as reaching the limit at block 994 . The subroutine then checks if the limits are being trained at block 998 . If yes, the limit training machine is updated at block 1002 . If no, the motor's power is set to zero and the motor state is set at the DOWN position in block 1006 . In block 1008 the subroutine returns.
If the motor has not been running for at least one second at block 990 , the subroutine sets the reason as early limit at block 1026 . Then the subroutine sets the motor power at zero and the motor state as auto-reverse at block 1028 and returns at block 1030 .
Returning to block 984 , the subroutine checks if the door's position is currently unknown. If yes, the subroutine skips to block 1004 . If no, the subroutine updates the door's distance from the DOWN limit using internal RAM microprocessor 300 in block 986 . Then the subroutine checks at block 988 if the door is three inches beyond the DOWN limit. If yes, the subroutine skips to block 990 . If no, the subroutine checks if the door is being positioned manually in the training cycle at block 992 . If yes, the subroutine skips to block 1004 . If no, the subroutine checks if the door is within the slow DOWN distance of the limit at block 996 . If no, the subroutine skips to block 1004 . If yes, the subroutine sets the motor slow down flag at block 1000 .
At block 1004 , the subroutine checks if a wall control command or radio command has been received. If yes, the subroutine sets the motor power at zero and the state as auto-reverse at block 1012 . If no, the subroutine checks if the motor has been running for over 27 seconds at block 1010 . If yes, the subroutine sets the motor power at zero and the state at auto-reverse at block 1012 . If no, the subroutine checks if the obstacle detector signal has been missing for 12 milliseconds or more at block 1014 indicating the presence of the obstacle or the failure of the detector. If no, the subroutine returns at block 1018 . If yes, the subroutine checks if the wall control or radio signal is being held to override the infrared obstacle detector at block 1016 . If yes, the subroutine returns at block 1018 . If no, the subroutine sets the reason as infrared obstacle detector obstruction at block 1020 . The subroutine then sets the motor power at zero and the state as auto-reverse at block 1022 and returns at block 1024 . (The auto-reverse routine stops the motor for 0.5 seconds then causes the door to travel up.)
The appendix attached hereto includes a source listing of a series of routines used to operate a movable barrier operator in accordance with the present invention.
While there has been illustrated and described a particular embodiment of the present invention, it will be appreciated that numerous changes and modifications will occur to those skilled in the art, and it is intended in the appended claims to cover all those changes and modifications which followed in the true spirit and scope of the present invention. | A movable barrier operator having improved safety and energy efficiency features automatically detects line voltage frequency and uses that information to set a worklight shut-off time. The operator automatically detects the type of door (single panel or segmented) and uses that information to set a maximum speed of door travel. The operator moves the door with a linearly variable speed from start of travel to stop for smooth and quiet performance. The operator provides for full door closure by driving the door into the floor when the DOWN limit is reached and no auto-reverse condition has been detected. The operator provides for user selection of a minimum stop speed for easy starting and stopping of sticky or binding doors. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is related to the following copending applications:
1. Ser. No. 447,015, filed Feb. 28, 1974, for Vocabulary and Error Checking Scheme for a Character-Serial Digital Data Processor.
2. Ser. No. 446,911, filed Feb. 28, 1974, for Structured Data Files in a Data Driven Digital Data Processor.
3. Ser. No. 447,034, filed Feb. 28, 1974, for Nested Data Structures in a Data Driven Digital Data Processor.
4. Ser. No. 446,912, filed Feb. 28, 1974, for Recursive Mechanism in a Data Driven Digital Data Processor.
5. Ser. No. 447,040., filed Feb. 28, 1974, for System and Method For Concurrent and Pipeline Processing Employing a Data Driven Network.
6. Ser. No. 447,017, filed Feb. 28, 1974, for Data Processing System.
BACKGROUND OF THE INVENTION
The present invention relates generally to improvements in digital data processors, and more particularly pertains to new and improved digital data processor systems wherein the data processor is a microprogrammed integrated circuit device.
In the field of digital data processing, it is presently the practice to employ system architectures that evolved under the influence of high hardware cost. This constraint resulted in centralization of system control into devices referred to as the central processor and main memory units. Because of this massive and expensive centralized hardware which needed to be controlled, operating systems (master control programs) were evolved to generalize its utilization, by sharing it across a number of programs or tasks. The system architectures which resulted from these influences are highly generalized and as a result, are unnecssarily, compley, ad hoc, and inefficient with respect to a large number of particular situations. This type of architecture is partitioned in an irregular manner and is implemented principally by hardwire sequential logic. Where micro-programming techniques are utilized, the basic system functional architecture is not changed in that the micro-coded processors still follow register oriented clocked sequential architectures.
The new integrated circit technology, such as MSI and LSI which provide the essential elements of a data processor on a single chip can be utilized effectively only if a new set of design constraints is followed. LSI technology, for example, requires hardware regularity and non-dedication of specialized or complex algorithms to circuit chips. Additionally, since integrated circuit memories are interface compatible with integrated circuit logic, the register oriented processor architecture scheme may be eliminated by distributing the system circuit memory through the system. This, of course, eliminates the need of a centralized main memory subsystem. Now that it is feasible to distribute system memory throughout a system, it is desirable to eliminate the previously required central control operating systems.
To be able to utilize LSI technology effectively, a system architecture which results in a well-formed and regular partitionable system is required. Even though nearly all microprogramming techniques utilized in the past have this underlying objective, prior art programming techniques have failed to produce system which is efficient program and efficient in execution of its algorithms. In other words, these prior art microprogrammed systems exhibit a total lack of continuity between what the machine language is and what the user programming needs and language demands are. This is true because the prior art machine micro-code languages are serial and binding in nature which is in direct opposition to the LSI technology demands for regularity, and non-binding of complex functions.
SUMMARY OF THE INVENTION
It is an object of this invention to provide digital precessor that may be used as a basic building block in a multi-processor computer.
Another object of this invention is to provide a digital processor for use as a building block in a multi-processor computer that would not need to utilize a master control program or require an extensive interrupt system.
A further object of this invention is to provide an electronic digital computer that has improved emulation capabilities.
These objects and the general purpose of this invention are accomplished by utilizing a multi-character vocabulary in a characterserial data processor wherein two of the characters are used to define the start and end of a particular data field. Each character is represented by a plurality of binary bits. Error checking of the data structures, which are made up of a plurality of nested data fields that may be illustrated as tree structures, is accomplished by counting only the characters representing the start and end of a field. The data structures permit expansion and contraction of the fields within it. A program or process is carried out in response to the linking up of a pair of data structures, one data structure containing the program, the other data structure containing the operands. Either data structure may be resident in the data processor's storage area (static) while the other is supplied to the processor from the outside (dynamic). Arrival of the dynamic data structure at the input of the data processor causes the mating data structure in storage to be addressed. If all operands for the addressed data structure are present or have arrived, the operation designated by the program data structure is performed, the result being transmitted to a destination indicated by the program data structure.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference numerals designate like parts throughout the figures thereof, and wherein:
FIG. 1 is a block diagram illustration of a single processor data processing system, according to the invention.
FIG. 2 is a logic diagram of the input queue in the processor of FIG. 1.
FIG. 3 is a logic diagram of the vector logic unit in the processor of FIG. 1.
FIG. 4 is a logic diagram of the control unit of the processor of FIG. 1.
FIG. 5 is a logic diagram of the output queue of the processor of FIG. 1.
FIG. 6 is a logic circuit of a signal recognition circuit utilized in the input queue of FIG. 2.
FIG. 7 is an abstract illustration of a four-character vocabulary utilized by the processor of FIG. 1.
FIG. 8 is an abstract illustration of the general structure of a data file utilized by the processor of FIG. 1.
FIG. 9 is an abstract illustration of a general data structure file that has subfiles within it.
FIG. 10 is an abstract illustration representing in tree form a particular example of a program that may be executed by the computer of FIG. 1.
FIG. 11 is an abstract illustration of a simple algorithm represented in tree form and the data structure or file representing that algorithm that is utilized by the processor of FIG. 1 to perform the specified operations.
FIG. 12 is an abstract illustration of a specific example of the interaction of program and operand data structure within the various major parts of the processor of FIG. 1 to produce a desired result.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1, illustrates a one processor data driven processor system communicating with a plurality of peripheral units 15, 17, 19 through an input/output exchange 13. The input/output exchange 13 may be a standard type of switching circuit such as that used in telephone exchanges in which any one of the peripheral units may be connected to the data driven processor 11 by way of input cable 31 or output cable 33. The peripheral units may be parallel or serial format units. To accommodate the character serial nature of the processor 11, when parallel format units are utilized the input/output exchange 13 would include a multiplexor to convert the plurality of parallel signal paths coming from the peripheral units 15, 17, 19 to the relatively serial signal path input to the processor 11. To accommodate the character-serial signal transmission from the processor 11 to the parallel format peripheral units 15 through 19, the input/output exchange 13 would include a demultiplexor. Peripheral units 15, 17, 19 may be any of the well known devices, such as, magnetic tape drives, card readers, card punch units, keyboard units, printers, or drum or disk storage devices.
The data driven digital computer or data processor 11 receives data structures from the peripheral units at its input queue 21. These data structures, as will be hereinafter explained, have a specialized organization and must follow certain syntax rules. The input queue 21 is basically a FIFO (first-in-first-out buffer unit) which performs the additional function of synchronizing the asynchronous data structures received on the input cable 31 to the system clock of the computer 11. The data structures received by the input queue 21, are received character serially. A commercially available FIFO buffer which may be adapted for use in the input queue 21 is disclosed in the Signetics Corporation 1972 parts catalogue, pages 7-135 to 7-138.
These data structures may be thought of as being communicated to the other elements of the processor 11 in a character-serial manner. Data structures in the input queue 21 are transmitted to computer storage 25, for example, in a character-serial manner over cable 35, to a control unit 23, and from the control unit 23 over cable 51 to computer storage 25. The control communication between the input queue 21 and control unit 23, over cable 37, and the control communication between the control 23 and the storage 25, over cable 49, will be hereinafter explained.
Besides data structures from the input queue 21 being transmitted to the storage 25, they may be transmitted to a vector logic unit 27 by way of control 23 over cable 47. Likewise, data structures from the storage 25 may be communicated to the vector logic unit 27 by way of control unit 23, over cable 45. Control communication between the vector logic unit 27 and the control unit 23, by way of cable 43, will be explained hereinafter.
Vector logic unit 27 is basically a serial arithmetic unit that performs, for example, such basic functions as addition, subtraction, compare and send-to on variable field length data structures. The vector logic unit may communicate directly with the storage 25, over data cable 53, and with an output queue 29, over data cable 59. The control communication between the vector logic unit 27 and the storage 25, over control cable 55, and with the output queue 29, over control cable 57, will be hereinafter explained.
The computer storage 25 of the data driven computer 11 may be a random access integrated circuit memory of a preferred size constructed from random access memory chips such as manufactured by the Signetics Corporation, for example. In their 1972 parts catalogue on page 4-24, Signetics Corporation lists a 32 by 2 random access memory chip that may be utilized in constructing the storage 25. The construction of a larger size memory with such a memory chip is considered as well within the purview of a person of ordinary skill in the art. Another example of a memory chip that may be utilized to build the storage 25 can be found in the 1972 Signetics catalogue on page 4-13 which illustrates a high speed cotent addressable memory chip.
The output queue 29 which may receive data structures from the vector logic unit 27, storage 25, or the input queue 21 performs the function of placing the data structures it has received into a form that may be transmitted to the peripheral units 15-19 by way of the I/O exchange 13. The output queue, like the input queue, is basically a FIFO buffer, accepting data structures in a character-serial manner and transmitting these characters to the I/O exchange.
Referring now to FIG. 2, the input queue 21 communicates with the I/O exchange over cable 31. Cable 31 is made up of lines 79, 81, 83 and 85 which eminate from our lead to interface logic 61 in the input queue 21. Lines 85 are two parallel data lines that receive two bits in parallel from the I/O exchange (FIG. 1). These two parallel bits represent a character. The other three lines 79, 81 and 83 are control lines between the input queue and the I/O exchange. Line 79 transmits a binary signal level that instructs the I/O exchange to retransmit the data structure whenever an error has been detected in the previously received data structure. Line 81 carries a binary signal level that enables or disables the I/O exchange in regard to the transmission of data structures. Line 83 carries a signal level generated by the I/O exchange which indicates a request to send data structures from one of the peripheral units or the output queue of the data processor 11. It would be in response to such a request signal level that the signal level on line 81 would enable the I/O exchange, if the input queue could hold additional data.
The character serial data structure received on lines 85 from the I/O exchange 13 (FIG. 1), besides being submitted to the interface logic 61 is checked for errors by logic circuitry, for convenience called "paren" recognition logic, and a binary up/down counter 65 that responds to the "paren" recognition circuit 63. The count of counter 65 is transmitted to the interface logic 61 over cable 93. Suffice it to say for the present, if the count of the binary up/down counter 65 at the end of a particular data structure is not zero, interface logic 61 requests a retransmit over line 79 because an error occurred in the data structure. The specific logic of paren recognition circuit 63 and its interaction with up/down counter 65 and the interface logic 61 will be explained more fully hereinafter.
As was noted above, the input queue 21 basically functions like a FIFO buffer and synchronizes the asynchronous incoming data characters with the computer system clock (not shown) that is part of the interface logic 61. The buffer portion of the input queue is the input queue memory 67 which may be a random access memory built from integrated circuit random access memory chips manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on page 4-20.
The data characters received on lines 85 from the peripheral units are transmitted to the input queue memory 67 over lines 96 where they are stored in the next available space as indicated by the wire pointer circuit 73. In between the storing of data characters in the input queue memory, data characters are being read out of this memory and transmitted to the other components of the processor 11 (FIG. 1) by way of the control unit 23 (FIG. 1). The particular data character that is read out of the memory 67, at a certain instant in time, is determined by the read pointer circuit 71. The data character that is read out of the input queue memory is transmitted from the input queue memory over lines 98 to the interface logic 61 and then to the control unit 23 (FIG. 1) over lines 35. The control lines 123. 121 making up the control cable 37, carry read enable and read request signals from the control unit 23 (FIG. 1). Line 123 carries a read enable signal. Line 121 carries a read request signal. Generally speaking, then, information is being stored into the input queue memory 67 as fast as it is received and it is being read out from the input queue memory 67 in a FIFO order as fast as the control unit 23 (FIG. 1) is calling for it. As the interface logic 61 receives data characters over lines 85, it generates a signal on line 97 to a memory cycle control unit 69 indicating that a write function is required. Memory cycle control, in response to this write request generates a write enable signal, on line 103, to the input queue memory 67, a write select signal, on line 105, to a selector 75, and an increment signal, on line 99, to a write pointer 73.
Selector 75 may be of the type manufactured by the Signetics Corporation and described in their 1972 parts catalogue on page 2-136. Basically, the selector, in response to a write or read select signal on line 105 chooses the write or read pointer output signal supplied to it on cable 109 and 111 respectively, to transmit over cable 107 to the address register of the input queue memory 67.
The write pointer 73 and read pointer 71 may be a binary counter manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on page 2-100. The incrementing inputs 99, and 101 to the write pointer and read pointer, respectively, from memory cycle control 69 would be connected to the A input (not shown) of these Signetics counters. Line 100 from interface logic 61 to both the read pointer 71 and write pointer 73 would be connected to the reset inputs (not shown) of these counters.
The outputs of both the write pointer and read pointer, besides going through the selector to address the input queue memory 67, are sampled by a comparator 77. The comparator may take the form of a comparator circuit manufactured by the Signetics Corporation and illustrated in their 1971 TTL/MSI parts catalogue on page 101. This comparator has two output leads which indicate which of the two inputs is larger, and when they are equal. Because the input queue 67 is functioning as a FIFO, that is, a first-in first out buffer, the write pointer count will always be greater than the read pointer count, whenever the input queue memory 67 has a data therein but is not full. Therefore, a signal on line 119 from comparator 77 will indicate to interface logic 61 that the write pointer count is greater than the read pointer count. This indicates to the interface logic that data still remains in the input queue memory.
Whenever the write pointer count equals the read pointer count, a signal is transmitted from the comparator, over line 117, to the interface logic 61. This signal can mean that the input queue memory 67 is either completely empty or completely full, depending upon whether the last memory request generated by the interface logic 61 was a read or write request. The interface logic 61 interprets the signal on line 117 as meaning that the input queue memory 67 is full if the last memory operation was a write operation. If the last memory operation was a read operation, a signal on line 117 is taken as an indication that the input queue memory is empty. The interface logic 61 knows if the last memory operation was a write or read operation since it transmitted either a write or a read request over lines 97, 95, respectively, to the memory cycle control 69. Whenever the interface logic 61 determines that the input queue memory 67 is empty, it generates a reset signal on line 100 to be supplied to both the write and read pointers.
The specific logic circuitry of the memory cycle control 69 and interface logic 61 will not be discussed herein because the implementation of the functions herein attributed to these logic circuits is viewed as well within the purview of a person of ordinary skill in the art.
Referring now to FIG. 3, a serial vector logic unit 27 that may be utilized in the computer of FIG. 1 is illustrated as consisting basically of two ROMs (read-only memories) 125 and 129. Both ROMs may be of the type manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on page 4-1. Address registers 124 and 128 for the read only memory 125 and 129, respectively, are standard parallel in parallel out address registers. The only structure difference between the two read only memories resides in the micro-code contained within them. Read only memory 125 contains the micro code required for generating the results of dyadic operations such as, addition, subtraction, or compare, for example. Read only memory 129 contains the micro-code required to generate the result of monadic operations such as complement, delete first bit, or first bit to zero, for example.
Data structures coming character serially from the storage 25 of the computer 11 (FIG. 1) by way of the control unit 23 over lines 45 to the vector logic unit 27 are directed by demultiplexor 135, according to a control signal on line 43a from the control unit 23, to the dyadic ROM 125 over line 139, or the monadic ROM 129 over line 142, depending upon what kind of data structure is being addressed by the data structure in the input queue 29. This will be more fully explained hereinafter.
Likewise, the demultiplexor 137 receives character-serial data over lines 47 from the input queue 21, by way of control unit 23, and routes it either to the dyadic ROM 125 over line 141 or the monadic ROM 129 over line 143. The output of either the dyadic ROM 125 or the monadic ROM 129 will be routed to the storage 25 of the computer or to the output queue 29 of the computer (FIG. 1), depending on the destination address contained within the program data structure. This destination address is supplied to demultiplexors 133 and 130 over lines 43d by the control unit 23 of computer 11 (FIG. 1).
The demultiplexors 135, 137, 130, and 133 utilized in this vector logic unit may be of the type manufactured by the Signetics Corporation and illustrated in their 1972 parts catalogue on page 2-132.
Assuming, for purposes of example, that a dyadic operation was to be performed, an operand A being summed with an operand B, an OP code designating the dyadic operation of addition would be supplied to the address register 124, either from the storage 25 or the input queue 21 of the computer, for reasons which will be hereinafter made clear. Along with this OP code, the two operands are also supplied, character serially, to the address register 124. As a result, the output on cable 126 of the read only memory 125 would be the character serial results of the summation of the two operands. Effectively, what is occurring is the OP code, in addition to the operands, act as addresses to the particular areas in the read only memory 125 that are storing the results of the summation of a particular two characters from the two operands being summed.
The output of the read only memory 125, in this particular example, would also contain a signal on line 43c that would indicate to the control unit 23 (FIG. 1) that a particular character summation has been completed. Also, in the case of addition, carry signals are propagated back to the input of the read only memory 125 on lines 132 to modify the next character addition. In case of monadic operations being performed with read-only memory 129, feedback lines 131 may simply be a stepping counter input to modify the contents of the address register 128 of the monadic ROM so that the next memory location is addressed.
In summary, the control unit 23 introduces data structures from the storage 25 and the input queue 21 to the vector logic unit 27 which responds to these two data structures by generating a result plus control signals, which are sent back to the storage 25 over lines 53 and 55, or to the output queue 29 over lines 57 and 59.
Refer now to FIG. 4 which illustrates the control unit 23 of computer 11 to be a microprogrammed unit consisting of a plurality of read-only memories and multiplexors. The field analyzer ROM 146 receives data structures from the input queue, over lines 35, or from storage, over lines 51b. Either the data structure from the input queue 21 (FIG. 1) or the data structure from storage 25 (FIG. 1) addresses the field analyzer ROM 146 through address register 145 causing the field analyzer ROM 146 to respond by sending control signals to one of the plurality of demultiplexors 148, 150 and 152.
For example, if the data structure coming in on line 35 from the input queue (FIG. 1) happens to be an operand file, the field analyzer would direct the demultiplexor 148 to transmit the operand fields over one of the three lines 47a, 39a or 51a, line 47a leading to the vector logic unit, line 39a leading to the output queue, and line 51a leading to the store. The field analyzer would, in this instance, be responding to the description field in the operand file. Likewise, if a data structure coming in on line 51b from storage (FIG. 1) happens to be operand file or field, the field analyzer ROM 146 would direct the demultiplexor 152 over line 162 to transfer the data over line 39b or line 45, line 39b leading to the output queue and line 45 leading to the vector logic unit.
Assuming now that instead of an operand data structure being received on either lines 35 or 51b, a program data structure is received. This program data structure would address the field analyzer ROM 146 causing it to transmit an address to one of the ROMs 154, 156, 158, by way of demultiplexor 150. The ROMs 154, 156, 158 make up a microprogram library that contains particular microprograms. These microprograms are addressed by the data structure coming in on either data lins 35 or 51b. Assuming that the data structure received by the field analyzer ROM 146 starts out with a field that indicates that what is to follow is a program file, the field analyzer would generate a plurality of signals to the demultiplexor 150 that would route the signals to program file ROM 154, for example. In response to thse signals addressing particular areas in this ROM, control signals are generated, over lines 43, to the vector logic unit (FIG. 3), over the line 41b, to the output queue (FIG. 5), over line 121, to the interface logic of the input queue (FIG. 2), and when appropriate, over line 144 to the address register 145 indicating that the particular operation is completed.
In addition to receiving data structures over lines 35 and 51b, the address register 145 receives various control signals. For example, over line 123 a read enable control signal is supplied from the interface logic of the input queue (FIG. 2). Over line 43c, an operation complete signal is supplied from the vector logic unit (FIG. 3). Over line 41a, the output queue (FIG. 5) supplies a hold signal instructing the control that it is full. A continue signal is also supplied to the signal register 145 from the ROM library over line 144.
The address register 145 is a standard parallel-in parallel-out register well known to those of ordinary skill in the art. The field analyzer ROM 146 may be of the type manufactured by the Signetics Corporation and listed in their 1972 catalogue on page 4-1. The microprogram library ROMs 154, 156 and 158 may be the same type. Demultiplexors 148 and 152 may be of the type manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on pages 2-132. Demultiplexor 150 may consist of a plurality of demultiplexors in cascade, the individual demultiplexors being of a type manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on pages 2-130.
Referring now to FIG. 5, the output queue 29 is illustrated as a dual-memory FIFO circuit. Input control circuit 145 receives data from either the input queue or storage over lines 39 by way of control unit 23 (FIG. 1). Lines 41 carry control signals from control unit 23 (FIG. 1). The input control circuit 145 also receives data from the vector logic unit 27 over lines 59 and, likewise, transmits and receives control from the vector logic unit 27 over lines 57. The data received by the input control 145 over lines 39 is routed either to the RAM (random access memory) operand memory 155 or the RAM destination address memory 157, depending upon whether the data structure received is a destination address, as determined by the signals on control line 41 from the control unit 23 (FIG. 1), or is an operand, as determined by the signals on control line 41. The data received on lines 59 by the input control 145 is routed to the operand memory or to the destination address memory, as determined by the signals on control lines 57.
Both the operand memory and destination address memory may be made up of RAM memory chips manufactured by the Signetics Corporation and listed in their 1972 parts catalogue on pages 4-20. Both memories are addressed by a write pointer or a read pointer, operand memory 155 having a write pointer 147 and a read pointer 163; destination address memory 157 having a write pointer 149 and a read pointer 161. The operation of these respective write and read pointers is identical to the operation they perform in the input queue when addressing the input queue memory 67 (FIG. 2).
The input control circuit 145 functions like the interface logic 61 in the input queue (FIG. 2) in responding to signals from comparators 151 and 153 to stop the transmission of information to the output queue 29 from the input queue, stoage, or the vector logic unit. The comparators 151 and 153, respectively, indicate to the input control circuit 145, in the same manner that the comparator 77 of the input queue of FIG. 2 indicates, that the respective memories are either full, empty or contain some data.
The output control circuit 159 of output queue 29 initiates a read request from either the operand memory or destination address memory RAMs 155, 157, respectively, in response to receiving a transmit instruction from the I/O exchange 13 (FIG. 1) over line 167 of cable 33. Output control 159 also responds to a retransmit signal over line 165. In response to signals on either one of these lines, the output control circuit 159 may transmit a request to write data signal on line 169 to the I/O exchange. Upon receiving a transmit signal over line 167, for example, the data structure, part of which is in both memories, is character-serially transmitted over lines 171 to the input/output exchange 13 (FIG. 1). It will be remembered that the input/output exchange 13 of FIG. 1, in response to receiving data structures over lines 171 from the output queue 29, will route such data structures according to the address field received from the destination address memory RAM 157. Thus, peripheral unit 1, 2 or N (FIG. 1) may receive the data or the data structure may be routed directly into the input queue of the computer 11, for further processing.
Referring now to FIG. 6, specific logic for the paren recognition circuit 63 (FIG. 2) is illustrated. The paren recognition circuit 63 has a pair of input conductors 175, 173, one each connected to the pair of input conductors in line 85. The signals on each one of these conductors 173 and 175 are supplied to the input of Exclusive OR gate 177 and, in addition, to an AND gate 179 over line 193 and an AND gate 181 over line 195. The output of the Exclusive OR gate 177 on line 191 is supplied as the other input to the respective AND gates. The output 89 of AND gate 179 generates a plus one up-count signal, whereas the AND gate 171 on output line 91 generates a minus one down-count signal to the up/down binary counter 65. The up/down binary counter 65 may be of the type manufactured by the Signetics Corporation and illustrated in their 1972 parts catalogue on page 2-170. The up/down counter 65 supplies a binary count over lines 197 to interface logic 61 of the input queue (FIG. 2) and receives a clock signal from the interface logic circuit 61 over line 199 of cable 93.
FIG. 7 illustrates the preferred two bit representations of the four characters utilized throughout the computer 11 (FIG. 1). The left data delimiter, for convenience called a left paren, 174 is represented by a high signal on a first line and a low signal on a second line, both signals being received substantially at the same time. A right data delimiter or right paren, 176, is represented by a high signal on the first line and a low signal on the second line, in direct opposition to the representation of the left data delimiter. A binary 1 character 178 is represented by two high signals. A binary 0 character 171 is represented by two low signals.
Referring again to FIG. 6, its operation in recognizing whether the signals being transmitted along line 85 represents a right or left data delimiter character, or a binary 1 or binary 0 character will now be explained. Assuming for purposes of example that the binary signal on conductor 175 is a 1, or high, and the binary signal on line 173 is a 0, or low, the output of Exclusive OR gate 177 will be a binary 1, and the signal on line 193 will be a binary one, causing AND gate 179 to generate a high signal level on line 89. This signal level causes up/down counter 65 to count up by 1. Assuming now that the binary signal on line 175 is a 0 and the binary signal on line 173 is a 1, representing a right paren character, the output of Exclusive OR gate 177 will be a binary 1, causing the output of AND gate 181 on line 91 to be high. The high signal level on line 91 causes up/down binary counter 65 to count down by 1. The count of up/down binary counter 65 is supplied to interface logic 61 of the input queue (FIG. 2). Whenever both input lines 173 and 175 to paren recognition unit 63 are high, no output is generated on either lines 89 or 91 because the Exclusive OR gate 177 does not generate an enabling signal on line 191. The same situation exists when both lines 173 and 175 are binary 0.
Referring now to FIG. 8, the field arrangement or general format of a data file which is the basic unit of a data structure is as illustrated. The first field of a file is a description field. The next following fields are data fields. The last field is a terminating field. The outermost left and right parens, 201 and 219, respectively, define a file. Assumng that this file which may be considered a simple data structure is being transmitted from left to right, the opening paren is 201 and the closing paren is 219. The first field that follows the opening paren 201 is a description field 203, which is itself delimited by a pair of parens. The next field to follow the description field may be an operand field such as illustrated by field 205, or an address field, or an operator field.
The data in the description field 203 will describe the type and order of appearance of the various fields that follow it. The spaces 207, 211 and 215 between the data fields 205, 209 and 213, may, for convenience, be called "empty space" which permits the data fields 205, 209 and 213 to expand, if necessary. When these fields contract,, they create more empty space. All this empty space may be used to later allow these fields to expand. The exact vehicle by which this occurs will be more fully described hereinafter.
The last field of every file is a terminating field 217 which usually will have no data within it. In other words, it is simply two characters, a left paren and a right paren. The terminating field 217 and the file closing paren 219 are three characters that represent the ending code for the data structure or file. This code then, according to the convention of FIG. 7, is ##EQU1## transmitted character-serially or two bits at a time, parallel from left to right.
This terminating field and the ending file paren is interpreted as a file ending code by the interface logic 61 of the input queue (FIG. 2). When this code occurs, the output of the counter 65 (FIG. 2) will be 0 if no errors had occurred in the data fields of the file. For example, the output count of counter 65 for the general file structure of FIG. 8 would proceed in this manner, 121212121210. Thus, a combination of a 0 count from counter 65 and the occurrence of the terminating code indicates that the data structure received had no errors therein. If, for example, there was an error in a paren character, the counter would not be incremented or decremented. If there was an error in a data character, the paren counter would be incremented or decremented incorrectly. In either instance, a count other than zero is left at the time that the terminating code occurs. This would indicate an error, causing the interface logic of FIG. 2 to respond by requesting a retransmit, as above described.
The structure of each file as generally illustrated in FIG. 8 must follow certain syntax rules. These rules are:
(1) No 1 or 0 characters can occur between like facing parens. For example, there can be no characters between the opening file paren 201 and the opening field paren of the description field 205.
(2) The first field of a file must be the description field 203.
(3) The last field of the file is always the terminating field 217. In our example, this field has no data therein.
A data field such as the A data field 205 of FIG. 8 may itself be made up of a plurality of fields or even a plurality of files. For example, FIG. 9 represents field A as consisting of three subfiles a, b and c. The opening field paren 221 and the closing field paren 223 define data field A. But, within these parens, a plurality of what shall be called "vector fields" may occur. Files a, b and c, 225, 229 and 233, respectively, illustrate vector fiels. These files, of course, must follow the general suyntax rules described for the general file of FIG. 8. That is, each file has within it a description field, data fields and a terminating field. As may occur within a file, the spaces between vector files within a field, such as 227 and 231, can permit for expansion of the vector files within that field, if desired.
This nested structure of fields within files and vector files within fields may be more readily comprehended if thought of in terms of a tree structure having nodes that represent programs or operators. For purposes of example, let us assume that the following defined operation must be performed on a plurality of literals represented by the capital letters of the alphabet:
{[(A+B)-(C+D)]+[(F+G)-J]}-{[(K-L)+(M-N)]+[O-Q])-R;56 →X
this arithmetic combination of 14 different literals may be represented by the tree structure shown in FIG. 10.
The tree structure of FIG. 10 receives as its inputs, at the leaf level 225, the literals, or other operands, that are to be operated upon by the program described by the various nodes 227, etc., of the tree. Thus, for example, the literals A and B are supplied to the add program operator at node 227; the literals C and D are supplied to the add program operator at node 229. The results of both operations are supplied to a subtract program operator at node 231. While this is occurring, the literals F and G may be supplied to another add program operator at node 235, the result of that summation being supplied to a subtract program operator at node 237, along with another literal J. Perhaps at the same time that these previous operations are occurring, the literals K and L are being supplied to a subtract program operator at node 239, the literals N and M are being supplied to another subtract program operator at node 241, and the literals O and Q are being supplied to yet another subtract program operator at node 247. The result of the operation at node 239 and the result of the operation at node 241 are supplied to an add operator at node 243.
The result of the subtract operator node 231 and the result of the subtract operator node 237 are supplied to another add operator node 233. The result of the add operator node 243 and the subtract operator node 247 are supplied to another add operator node 245. The result of the add operator 245 is supplied to the subtract operator node 249 which is also supplied another literal R. The results of the minus operator node 249 and the add operator node 233 are supplied to another subtract operator node 251. The result of this node supplied to the send-to-X operation 253.
As is apparent from this description of the tree structure, the processing of operands in a tree structured flow facilitates the processing of operands in a concurrent manner. That is, the operations occurring on the same level such as nodes 227, 229, 235, 239, 241 and 247, may all occur substantially simultaneously if the appropriate operands are available. The same is true for all operations on another, or second, level, such as nodes 231, 237 and 243, if the results of previous operations are all available simultaneously.
The example of FIG. 10, for the purposes of simplicity of description and ease of understanding only considered dyadic operations such as add and subtract. However, it should be understood that this type of tree structured process flow will accommodate monadic and dyadic operations with equal facility. It should be understood that to take advantage of concurrent processing a system of data processes must be utilized.
To illustrate how the nested file data structures of FIG. 8 and 9 implement the tree structured processing concepts, the following simple dyadic operations on four literals will be considered: (A+B)-(C+D). These operations are illustrated in tree structured form in FIG. 11. The literals A, B, C, and D at the leaf level 255, 257, 259, 261 are supplied to the first level of operator nodes, the summing nodes 263 and 265. The results from this node level are supplied to the next level or subtracting node 267. The result of this node 269 may be sent to another node or, program operator, or a physical destination.
Each node of the tree structure, FIG. 11, can be considered to be a file. Therefore, looking at these two levels of node operators, the file that would describe the subtraction node 267 is illustrated as subtract node file 271. This file is deliminted by right and left parens, and has a first field that is a description field 277 that describes the nature and sequence of the file. In this instance, P represents program, meaning that this file is a program operator file. Since this file is an operator file the next field to follow the description field will be a field 279 containing the operator code, OP. In our example, the operator code describes a subtract operation. Since the operation is dyadic, the fields that follow the operator field describe the two operands to be subtracted. These two operands ar the results of add nodes 263 and 265.
Because the operands are results of other operations, the operand fields are vector files. Therefore, the operands are described by the vector files 273 and 275. The field that follows the operand fields is a destination address field 287 that indicates the destination to which the result of the subtract operation must be sent. The last field of the subtract file is the terminating field 289. Empty space may occur at any place between fields within a file. For example, within the subtract program file, empty space is illustrated as occurring at 281, 283, and 285. It should be remembered that since the operand fields of the subtract program file are vector files, empty space may also occur between the fields within these files.
Consider now the two vector files within the subtract program file, the add vector file 273 and the add vector file 275. These files are again structured according to the syntax rules described above. There are left and right file delimiting parens. Within these parens the first field is a description field which in this instance describes the file as a vector file, thereby reserving the next following field for the operator code. For our example, an add operation is described. The fields that follow the OP field will be the operand fields which, in our example, are literals. In addition to operand fields, the dyadic vector files such as files 273 and 275 within a larger file, such as program file 271, contain resultant fields, denoted by R in FIG. 11. These resultant (R) fields store the result of the dyadic operation described by that vector file if that result cannot be used at the time that it is generated.
In order to facilitate understanding, the general operation of the computer 11 of FIG. 1 will be described in relation to the simple program flow illustrated in FIG. 11, which only utilizes dyadic operators. To further facilitate explanation and understanding, it will be assumed that the program data structures or program files are dynamic and received by the input queue 21 (FIG. 1). It should be understood, however, that the reverse is equally applicable and that the operand files may be stored in computer storage 25 and the program files may be supplied to the computer 11 by way of input queue 21.
In order to perform the function flow of FIG. 11, the storage of the computer will contain a program file as illustrated in FIG. 12B, under the "storage" heading. The initial contents of this file, prior to the computer receiving any operand files, is illustrated at position "1". The first field 291 of this file is a description field, that identifies the file as a program file. The first field, 301, following this description field is a field describing the operation to be performed. For our example, it is a subtract operation. The next field to follow the operator field 301 is an operand field delimited by a left paren 305 and a right paren 327. This operand field is a vector file that represents a dyadic operation. Following this operand field is a second operand field that is also a vector file. The field immediately preceding the terminating field is a destination address field 343. It should be remembered that space may be provided between the varius fields of the subtract program file so that spaces 303, 329, etc., provide for the expansion of the operand fields.
Consider now the first operand field, which is a vector file. In this particular instance, an addition operation is defined. The operand fields 309 and 313 of this particular file, since it defines a dyadic operation, follow the field describing the operator. In addition, this vector file contains a result field 321 instead of a destination address field. The operand fields 309, 313 and result field 321 are all in a contracted state, leaving a considerable amount of empty space 307, 311, 315 and 323 between them. In other words, the fields are simply defined by a left paren followed by a right paren with no characters in between. Thse operand fields remain contracted, as will be more fully described hereinafter, until operands are stored therein.
The second operand field for the subtract program file is also a vector file structured in the same manner as described for the first operand field. There are a pair of operand fields 333 and 335, a result field 337 and a terminating field 341. When these fields are empty, they are in a contracted state leaving a considerable amount of empty space 331, 339, etc. between them.
The above describes the contemplated structure of a program file within the computer storage which remains static in storage until an operand data structure or file arrives at the input queue addressing this particular program file. The structure of this program file provides a recursive mechanism that speeds algorith, execution.
An alternate data structure for performing the function flow of FIG. 11 would be one that utilizes three program files, instead of one program file containing two vector files, as illustrated. Thus the two add vector files and the subtract program file represent three independent program files. The resultant (R) field of each vector file would be replaced with a destination address (DA) field. The destination address field in both add program files would address the subtract program file, in a manner to be disclosed hereinafter. Utilizing this type of data structure requires that the result of each operation be routed out of the computer and back to its input to get to the next operator node. In contrast, the illustrated program file structure eliminates the necessity of sending the result of a vector file operation out of the processor and back to its input for further processing.
To continue with the illustrated data structure, consider now the data files arriving at the input queue. Assume that the first operand to arrive in a data file is the operand A. The file that contains this operand is illustrated in FIG. 12A as file structure 1 under the "input queue" heading. The first field of this data file is a description field 375 that indicates that this particular file is an operand file containing a literal. This description field is analyzed by the field analyzer 146 (FIG. 4) of the control 23, which in response thereto sets up the appropriate paths to computer storage 25 for the next field 377 which is a storage address field addressing the particular vector file to which the literal A belongs. The storage address 377 will address the location in computer storage that starts with the left paren 305 of the add vector file within the subtract program file 301. The next field following the address field 377 is an operand location field 379 that indicates whether the operand field 383 that follows belongs in the left or right operand field 309 or 313, respectively, of that particular vector file. The operand file being received at the input queue also has a terminating field 387 and may have empty space 381, 385 between the fields of the file.
The control 23 by way of its field analyzer ROM 146 and its subroutinge library consisting of the plurality of ROMs 154, 156, 158 interrogates the add vector file, after it has been addressed by the operand file at the input queue, to determine if the B operand has previously arrived and is stored within its field 313. Since, in this case, it has not, as is indicated to the control by he empty operand fields 309, 313, the control stores the operand A in the appropriate field 309. As the operand A is written into memory, character by character, the operand file 309 is expanded to accommodate its exact size. The specifics of how the operand is actually written into memory are seen as well within the purview of a person of ordinary skill in the art, and will not be discussed herein.
As a result, therefore, of the literal file illustrated at position 1, arriving at the input queue, the subtract program file in computer storage will have the literal A stored within the appropriate operand field 347 of the vector file which was addressed and begins with the left paren 345, as shown at position 2 under the "storage" heading of FIG. 12B. Since the literal A is now stored within its appropriate operand field, that field has been expanded and the empty space 349 between this operand field and its companion operand field may be completely used up or greatly diminished.
Assume now that the next operand file that comes into the input queue 21 of the computer 11 (FIG. 1) contains operand D is its operand field 382, as shown in position 2 under the "input queue" heading. Besides the description field that tells the control unit the fields that are to follow, a storage address field 376 and an operand location field 389 are present in this operand file. The literal file at position 2 of the input queue has a storage address field 376 that addresses the add vector file within the subtract program file at the starting paren 346 (position 2 under "storage" heading). Once this vector file is addressed, the control unit, upon seeing the operator field of the vector file will cause the appropriate addition microprogram in the microprogram library, made up of ROMs 154, 156 and 158 (FIG. 4) to be activated. If this microprogram detects that all the operands that are necessary to perform the operation are not present, either in the input queue or the storage of the computer, another microprogram is activated for storing the literal D in operand field 382 of the input queue file in the appropriate operand field 351 of the add vector file, as determined by the operand location code in field 389 of the literal file at the input queue. As a result of the second literal file having been processed, the data structure in storage will appear as illustrated at position 3 under the "storage" heading. That is, a literal A is stored in its appropriate operand field in the first add vector file and a literal D is stored in its appropriate operand field in the second add vector file.
Assume now that the third operand field to come into the input queue carries a B operand in the operand field 384 that is to be combined with the A operand. The controller recognizes, because of the description field L, that this is a literal file and, therefore, the following field 378 is a storage address that addresses the first vector file containing the A operand. The controller proceeds to read this addressed vector file; and its field analyzer ROM 146 (FIG. 4) determines from the description field "V" that it is a vector file containing a program. The field that must follow this description field is then an operator code field. In response to the operator field, the field analyzer actuates the appropriate microprogram from the microprogram library ROMs 154, 156 or 158 (FIG. 4) and additionally causes the reading out from storage of the literal A to address the appropriate ROM 125 in the vector logic unit (FIG. 3), while at the same time reading out the literal B from the input queue to address the same ROM 125 in the vector logic unit.
It should be recalled that the vector logic unit is a serial arithmetic unit that operates on two characters at a time, one character from each of the two operand fields. When the vector logic unit has completed its function of adding operand A and B together, the microprogram determines if the resultant field in the second vector file is full. Since in this instance it is empty, it will store the result of the addition of literals A and B in the appropriate resultant field in the first vector file. As a result of the third operand file appearing in the input queue, the subtract program file in storage will be structured as shown at possition 4 under the "storage" heading, that is, the operand fields that literals A and B occupied fields 355 and 359, respectively, are now empty, since they were contracted as read; and the resultant field 359, containing the result of the summation of A and B, is full. The literal D as an operand of the second vector file is also present.
The only missing operand, at this time, is the C literal. Assume now that an operand file comes along containing the C operand in field 386. The control recognizes that this is a literal file and closes the appropriate paths so that the storage address field 380 may address the second vector file. The control will then read this vector file, set up the vector logic unit to perform the operation required by the operator code field therein and proceed to sum C and D in the same manner as described for operands A and B. Upon completion of this operation however, since the resultant field 369 of the first add program subfile is full, besides storing the result of the summation of literals C and D in the resultant field 367, another microprogram is chosen which conditions the vector logic unit according to the subtract operator code field in the subtract program file. This microprogram causes the control unit to supply to the vector logic unit, in character-serial manner, the resultant of the A plus B summation from the resultant field 369 in the computer storage, as the result of C plus D is supplied thereto, to have the two results subtracted.
While this operation is being performed, the destination field 343 of the subtract program file is supplied to the destination address memory 157 of the output queue 29 (FIG. 5). This destination address field 375, as shown in FIG. 12B under the "output queue" heading in position 1, is a destination vector file that has as its first field a description field 381, which, in our example, identifies the file as a literal or operand file; an address field 383 following it; and an operand location field 385 following the address field. Operand fields, such as field 387, may follow the operand location field. Since the syntax of a file structure must be followed, the destination address file terminates with a terminating field 391. The destination address field, since it is a vector file, may also have empty space between he fields within it, such as empty space 389, for example. The operand field 387, at this point, has nothing stored within it and is in contracted form. When the vector logic unit obtains the result of subtracting the literals C+D from the literals A+B, that result as shown in position 1 under the "operand memory" heading of FIG. 12B is sent to the operand memory 155 of the output queue (FIG. 5).
The output control 159 of the output queue 29 (FIG. 5) transmits a message in a form that is essentially identical to the form that is received at the input queue as shown in FIG. 12B under the "message transmitted" heading. Since, in our example, the result is a literal, the transmitted file is an operand file, delimited by a right paren 377 and a left paren 379. The first field is a description field 381 defining the file as an operand file. The second field is an address field 383. This address field, as shown in FIG. 12B, may be a simple field containing a peripheral unit designation 384, or, in case of a multi-processor system, it may contain compound fields such as a field 386 defining a processor unit and a storage address field 388, defining a specific area in the storage of the addressed processor. The field following the address field is an operand location field 385, if needed. The field following the operand location field is the result field 393. The operand file leaving the output queue ends with a terminating field 391 and a right paren 379.
In summary then, the above functional description makes it clear that the computer of FIG. 1 executes an operation only after two data structures are linked, one being a program structure, the other being an operand structure. In the case of the specific example, the program structure in the form of program files are stored in computer storage awaiting the arrival of the operand structures or operand files that address the appropriate program files, causing the control unit of the computer to execute the designated program. This data driven operation, therefore, provides a digital processor that has superior emulation capabilities, and may be used as a basic building block in a multi-processor computer, each of the building blocks having their functions defined by the program files stored within their respecting storage areas. Since the arrival of operand files at the input of a specific processor causes the activation of the addressed program when such a processor is utilized as a building block in a multi-processor computer a master control program or extensive interrupt system which would regulate the interaction of the processors within the multi-processor computer is not required.
It should be understood, of course, the foregoing disclosure relates only to a preferred embodiment of the invention and that numerous modifications may be made therein without departing from the spirit and scope of the invention as set forth in the appended claims. | A character-serial electronic digital computer utilizing a four character vocabulary, each character being represented by two binary bits, is structured to process character-serial data arriving at the computer in a manner specified and initiated by the arriving data. Data structures that may represent program or operations to be performed on data arriving at the computer input are stored in the computer's storage area in the form of nested data structures that may be illustrated as tree structures in which each node of the tree structure represents an operation. Data structures that may represent operands are also supplied to the computer in a nested organization. This operand data addresses a certain node or operation resident in the computer storage area. The linking up of the arriving operand data with its program data triggers execution of the operation. In a case where more than one operand is needed before an operation can be performed, the arrival of a first operand without the second causes storage of the first operand until arrival of the second arrival of the second operand triggers the operation to begin. This interrelationship of program data and operand data, that is, the dynamic data being linked with the static data to trigger the operation, exists whether the program data is stored and static or the operand data is stored and static. Utilizing a four character vocabulary, to represent data, two of the characters being utilized to indicate the beginning and end of a data field, facilitates the implementation of an error checking technique wherein only sensed characters indicating the beginning and end of a data field are counted. The utilization of beginning and end of data field characters in the data structures consisting of nested data fields permits at will expansion and contraction of the fields within it. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a white light emitting diode (LED), an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder, and more particularly to a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder that apply several white light nitride heterostructures capable of emitting color lights to show the features of a strong yellow color and a yellowish orange color that have a high quantum light emitting efficiency and a durable light emitting time.
[0003] 2. Description of the Related Art
[0004] Since 1968, the light emitting diode technology has started using phosphor powder and a specturm conversion structure that uses phosphor powders as a base extensively. At early times, a converter that improves the light emitting efficiency makes use of the effect of an anti-Stokes phosphor powder to convert the near infrared light of GaAsP diodes into a red light or a green light (refer to Berg, Din A., LED, <<Mir>>, 1975). Thereafter, many researchers tried to convert the weak ultraviolet light of GaN diodes into a visible light.
[0005] The experts (including S. Nakamura and S. Shimizu) of Nichia Company have achieved breakthroughs in the researches of this subject and developed a new light source by the blue light of a GaInN heterostructure and a yellow alumium yttrium garnet phosphor powder (Y 3 Al 5 O 12 ) (refer to German Pat. No. DE6933829T issued to S. Nakamura on Nov. 5, 2006 and R.O.C. Pat. No. TW156177B issued to S. Shimizu Y on Nov. 1, 2005).
[0006] The acheivements of these two paented inventions are applied to the illumination, lamp decoration and indicating purpose of the white light emitting diode. Refer to the patent specification (R.O.C. Pat. No. TW156177B issued to S. Shimizu Y. on Nov. 1, 2005), the use of aluminum yttrium garnet phosphor powder in light emitting diodes is described in details. However, we do not believet that such invention is novel, and the novelty of its prototype mentioned in the specification include: 1. using a GaInN heterostructure that emits a blue light as the structural foundation of light emitting diodes; 2. adopting phosphor powder particles with an enhanced light transfer effect in light emitting diodes; 3. mixing two portions of emitting lights such as the direct light emission of the GaInN semiconductor heterostructure and the light emission activated by the phosphor powder particles to produce a white light; and 4. adopting an aluminum yttrium garnet with a chemical formula Y 3 Al 5 O 12 :Ce and its derivative such as a phosphor powder composed of (Y,Gd) 3 (Al,Ga,Sc) 5 O 12 :Ce particles. There are many journals and literatures regarding the GaInN semiconductor heterostructure that emits blue lights, but S. Nakamura and G. Fasol et al have made technical disclosures on 1998 (refer to S. Nakamura and G. Fasol, The blue laser diodes. Berlin, Springer, 1998) and cited a portion of the GaInN semiconductor heterostructure that emits blue lights. The achievement of a high performance light emitting nitride heterostructure produced accroding to the quantum effect of S. Nakamura's study has become a public domain, and all of these are considered as Nichia Company's efforts and contributions. As mentioned above, the enhanced light transfer powder used for light emitting diodes is made of an anti-Stokes material (refer to Berg, Din A., LED, <<Mir>>), 1975) and gone through a skillful technique. A short wave radiation used for activating various different matters to emit lights has been described in details in many acacemic theses (refer to P. Pringshein, Phluorescence and phosphorescence, IL, 1950; G. Blasse, P. Grabmaier, Luminescence materials, Pergamon press, NY, 1995; and S. Shionoja, W. Yen, Handbook of phosphors, NY, 1999). We believe that the method of using a light emitting diode to emit short wave radiations to obtain long-band radiations from phosphor powders is not novel or has any significant feature. There are many light sources for emitting ligth by activating other matters, and these light sources include gas discharge light sources: 1. gas discharge of mercury vapor; 2. gas discharge of nitrogen; and 3. gas discharge of xenon and krypton. In addition, laser radiations are used extensively for activating phosphor powders to emit lights such as nitrogen lasers and Nd:YAG lasers for outputting third harmonic waves and fourth harmonic waves.
[0007] The solution of using semiconductor light emitting diodes to activate phosphor powders has been mentioned for more than one time (refer to S. Nakamura and G. Fasol, The blue laser diodes. Berlin, Springer, 1998).
[0008] The related matters of combining two or more basic light sources to obtain a white light are described below. The physical base of combining monochromatic lights such as blue light and yellow light, green light and red light, red light, green light and blue light obtained from the occurrence of a dispension of color to produce a white light was established by Newton and developed from Newton's light color theory. The phsycial principle was used extensively in the areas of printing and photography and particularly in black-and-white and color television technologies during the 19 th and 20 th centuries. Vladimir Zworykin's black-and-white cathode ray tube utilizes a blue color light and a yellow color light as two basic lights to emit a white light (refer to H. W. Leverenz, An introduction to Luminescence of Solids, NY, 1950), and it is a complicated technical solution for color television technology, not only requiring primary color lights that have complete chromatic aberration coefficients, but also requiring a compensation of primary colors to obtain a white ligth that can meet the standards of color chromaticity.
[0009] In the technical field of illuminations, the problem similar to the foregoing physical theory has been solved (refer to L. M. Kogan LED lighttechnic, Moscow, Ho. 5, pp. 16-20 (2002)): a mercury vapor discharge emits a blue color light and activates YVO 4 :Eu to emit a red color light and finally produces a white light similar to a white light source. The short wave discharge of xenon and krypton assures that the gas discharge ion panel can produce red, green, blue white color lights. Therefore, the technological advance of using a semiconductor light emitting diode to replace a gas discharge light source to activate the phosphor powders and emit lights for perfect illuminations, information, indicating system becomes a trend.
[0010] The blue light source for producing different optical effects can be used extensively. The blue light source for producing long afterglows and super long afterglows is used extensively in the radar positioning technology. The original blue light and yellowish white afterglow optics of a light emitting display device are integrated organically into a device.
[0011] Therefore, the physical theory of a white light free of chromatic aberration and syntheszed with two or three light sources has been disclosed and used publicly before Nichia Company announced its research achievements.
[0012] The use of yttrium aluminum garnet as a luminescence material causes many ligitations, because only Nichia Company has the right of using such material (and thus a new research direction shows up, and a luminescence material other than the yttrium aluminum garnet is used for light emitting diodes), and such right was proven later as lack of legal grounds. Firstly, the luminescence materials and display devices made of a yttrium aluminum garnet have been disclosed earlier in the research achivements by Japanese researchers (refer to G. Blasse, P. Grabmaier, Luminescence materials, Pergamon press, NY, 1995; S. Shionoja, W. Yen, Handbook of phosphors, NY, 1999.; H. W. Leverenz, An introduction to Luminescence of Solids, NY, 1950 and V. A. Abramov, patent USSR No. 635813, Sep. 12, 1977). The chemical material Y 3 Al 5 O 12 or (Y,Gd) 3 (Al,Ga) 5 O 12 :Ce is used extensively in a high speed cathode ray tube techology to detect black-and-white or color films. The blinking devices using powder yttrium aluminum garnets or single crystal yttrium aluminum garnets as its structureal base are applied in nuclear physics and nuclear technology. In the meantime, the physcial correction technology of spectrum is also used, and the main physcial properties of the YAG luminescence material include the features of a high light emitting efficiency, a very short afterglow, a hightly reliable luminous flux and power, and emitting bluish green color, green color, yellow color and orange color in the bands of visible lights. Such technology has been used at earlier time before Nichia Company applied garnet phosphor powders to light emitting diodes. Therefore, we believe that the research achievements of the garnet phosphor powder made by Nichia's experts have not exceeded a reasonable level of knowledge for the direct use of phosphor powder. In the meantime, it lacks of legal grounds to include all light emitting materials that use cerium as an activator in Nichia's patent rights. The well-known luminescence materials such as orthosilicates of Al 2 O 3 :Ce, gelenite:Ce, yttrium, gadolinium, and lutetium and pyrosilicates of Y 2 Si 2 O 5 :Ce, Gd 2 SiO 5 :Ce, and Lu 3 Si 2 O 7 :Ce are used extensively in the production related to the flurorescence technology and definitely are not related to the Nichia Company's patented invention in practical applications.
[0013] Based on the foregoing analysis, the following conclusions are drawn: 1. The technology of using phosphor powders and enhanced light transfer apparatuses in various different types of light emitting diodes has been disclosed and known at an earlier time. 2. The method of combining two or more basic lights to produce a white light is well known in the art, and its physics and color chromaticity theory are obvious. 3. The main composition of luminescence material that uses cerium as an activator for a yttrium aluminum garnet compound has been disclosed in 1965 which is much earlier than the Nichia Company's invention. 4. The Ce +3 is used for activating a luminescence material of various different crystal structures. 5. The Nichia Company's garnet phosphor powder related patents are not novel, and these patented inventions are technical solution of using a blue color light to achive a white light only, which is definitely a blemish.
SUMMARY OF THE INVENTION
[0014] In view of the shortcomings of the prior art, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally invented a white light emitting diode (LED), an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder in accordance with the present invention.
[0015] Therefore, it is a primary objective of the present invention to provide a feasible solution and overcome the foregoing problems by providing a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder that can be applied to light emitting diodes and have new componsitions and features.
[0016] Another objective of the present invention is to provide a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder that can selectively adopt a nitride heterostructure with a radiation wavelength from 440 nm to 475 nm as a good composition for producing phosphor powders that radiate various color temperatures.
[0017] A further objective of the present invention is to provide a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder selectively used as an enhanced light transfer material for a nitride heterostructure.
[0018] Another further objective of the present invention is to provide a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder that optimize the overall structure including an optical thickness of an enhanced light transfer layer of the light emitting diode and a component filled or submerged in the internal chamber of the light emitting diode.
[0019] To achieve the foregoing objectives, a phosphor powder in accordance with the invention applied in a white light LED that uses an oxide of Groups II or III element in the periodic table as a substrate, and an element with an electron jump from d orbital to f orbital as an activator, and the substrate of the phosphor powder is composed of solid solutions of barium and yttrium aluminates, and its chemical formula is Ba α Y 3β Al 2α+5β O 4α+12β , and the crystal system of its crystal lattice varies with the ratio of barium to yttrium. If the substrate is activated by a short wave radiation, the ions of the element radiates a greenish orange color light mixed with a short wave radiation produced by an indium gallium nitride semiconductor heterostructure to form a white light.
[0020] To achieve the foregoing objectives, a white light LED in accordance with the invention comprises an InGaN semiconductor heterostructure and an enhanced light transfer powder, wherein the enhanced light transfer powder is comprised of a polymer substrate and phosphor powders, and the degree of polymerization of its structural base is equal to 100˜500, and the molecule quality is larger than an epoxy resin or an organosilicon resin having 5000 standard carbon units, and 1%˜50% of phosphor powder is filled to form a polymer layer with an even thickness on the light emitting surface of the heterostructure, and this layer can convert the original radiation of the short wave heterostructure into a white light with a ratio color temperature from 3200K to 6000K, and the color chromaticity of its emitted light is Ra≧85.
[0021] To achevie the foregoing objective, a method of producing phosphor powder in accordance with the present invention comprises the steps of: performing a solid phase sintering for oxides and carbonates; continuing the solid phase sintering for several hours in a high temperature environment; and performing an ignition at a high temperature in a reduction environment.
[0022] To achevie the foregoing objective, a method of producing phosphor powder in accordance with the present invention comprises the steps of: using hydroxides as raw materials; and adding and mixing the hydroxides with an approriate proportion into a melted barium hydroxide.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a flow chart of a method of producing phosphor powder according to a preferred embodiment of the present invention;
[0024] FIG. 2 a flow chart of a method of producing phosphor powder according to another preferred embodiment of the present invention;
[0025] Attachment 1 shows a spectrum-color temperature feature of a solid solution synthesized of ¼ m of BaAl 2 O 4 and 1 m of Y 3 Al 5 O 12 ; and
[0026] Attachment 2 shows a light emitting spectrum of a phosphor powder synthesized of 0.5 m of BaAl 2 O 4 and 1 m of Y 3 Al 5 O 12 and activated jointly by Ce +3 and Pr +3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0027] The present invention provides a novel phosphor powder and its basic enhanced light transfer powder, and the phosphor powder uses an oxide of Groups II and III element in the periodic table as a substrate, and a d˜f element as an activator having the following characteristics: The substrate of phosphor powder is composed of solid solutions of barium and yttrium aluminates or their equivalents, and the chemical formula is Ba α Y 3β Al 2α+5β O 4α+12β , wherein α has a value within the range of α≦1 or α≦1, and β has a value within the range of β≦1 or β≧1. The cyrstal system of the crystal lattice varies with the ratio of barium to yttrium. If α≦0.1, the crystal lattice is a cubic crystal system; if α=1, β≦0.1, the the crystal lattice will be a hexagonal crystal system; and if α=1, β=1.0, the crystal lattice will be a monoclinic crystal system. A f element and a d element such as Ce, Pr, Eu, Dy, Tb, Sm, Mn, Ti or Fe is added into the foregoing compound, and these elments have different oxidation levels within +2˜+4. If the substrate compound is activated by a short wave radiation with λ≦470 nm, the foregoing ions will emit a greenish orange color light with a wavelength λ=530 nm˜610 nm mixed with a short wave radiation emitted by the indium gallium nitride semiconductor heterostructure to produce a white light.
[0028] As to the physical chemistry, the experiements of the present inveniton show that aluminates of Group II elements such as MeAl 2 O 4 (if Me=Mg or Ca, a compound MgAl 2 O 4 with a spinel type and a cubic crystal system is formed) or a compound Me 4 Al 7 O 15 have similar optical properties of the yttrium aluminate. If these compounds are activated by Ce +3 ions, a strong light will be emitted, and a light beam with λ=450˜470 nm will be activated by the blue light diodes.
[0029] The experiments of the invention also show that if a solid solution is formed by mono aluminates and poly aluminates of Group II elements and Y 3 Al 5 O 12 garnet type yttrium aluminates or calcium titanium YAlO 3 type yttrium aluminates, the emitting light will be stronger. The composition of this solid solution contains integral MeAl 2 O 4 type mono aluminate. For instance, a unit yttrium aluminum garnet may contain 1, 2, 3 or 4 units of mono aluminates. However, it may contain a solid solution with a non-integral unit of mono aluminates, such as MeAl 2 O 4 may have a number of 0.1, 0.25, 0.4 or 0.5. The solid solution formed by aluminates of Group II element and yttrium aluminate may contain less yttrium aluminate. Under this situation, if α=1, β≦0.1, a crystal structure of the solid solution will be substantially a hexagonal crystal system; if α≦0.1, β=1, the crystal structure will bve substantially a typical cubic crystal system of the yttrium aluminate garnet. Now, the parameter of the cystal lattice approaches a=12.4A°, which is larger than the parameter of the cystal lattice of the standard yttrium aluminum garnet. However, Ce +3 ions in the crystal lattice with this parameter can be dissolved more easily (its solubility may be over 15%, and the average solubility of Ce 2 O 3 in the standard yttrium aluminum garnet does not exceed 3%).
[0030] If α≦1, and β≦1, the crystal lattice structure of the solid solution will be loose, which belongs to a monoclinic crystal system (a,b,c, γ).
[0031] The solid solution formed by aluminates of Group II elements and yttrium aluminates can dissolve larger ions such as Ce +3 very well. The ions of light rare earth elements including Ce +3 and Pr +3 can be dissolved in the solid solution very easily. The ions of heavy rare earth elements including Dy +3 , Tb +3 and Eu +3 and the Sm +3 at a borderline can be dissovled in the solid solution. Now, the Eu +2 and Sm +2 having a variable valence state may simultaneously have two different oxidation states: +2 valence state and +3 valence state, and Mn +2 and Mn +4 , Ti +3 and Ti +4 , Fe +2 and Fe +3 may exist simultaneously or seprately in a crystal lattice structure of the solid solution. The foregoing ions have the property of emitting strong lights (wherien the ion such as Ti +3 gaining this light emitting property again). The bands of the lights activated by all of the foregoing ions (Dy +3 , Tb +3 , Mn +4 and Ti +3 ) with a strong light emission is close to a near ultraviolet band or a blue light band with λ=440 nm in a visible light spectrum.
[0032] The present invention performs a detail analysis of the radiating spectrum of the d element and f element syntheized in the solid solution as shown in Attachment 1 . Attachment 1 shows a spectrum-color temperature composed of a solid solution synthesized by ¼ m of BaAl 2 O 4 and 1 m of Y 3 Al 5 O 12 . The most significant characteristic of emitting light activated by the Ce +3 includes a bell-curve spectrum having a larger half width value of spectrum.
[0033] Attachment 2 shows a light emitting spectrum actiavated jointly by Ce +3 and Pr +3 in the phosphor powder which is synthesized by 0.5 m of BaAl 2 O 4 and 1 m of Y 3 Al 5 O 12 . The characteristic resides on that Pr is a +3 valence state ion, and its light emitting spectrum is situated at a long wave band at λ=610 nm˜615 nm.
[0034] The foregoing novel compound that uses several activators has the following advantages: 1. The band covered by the light emitting spectrum of phosphor powder is wider than the previous one. 2. A small quantity of second or third kind of activator is added to change or modifiy the original color of the emitted light. 3. A light of a different frequency can be selected for the activation to change the color of light emitted by the phosphor powder.
[0035] The stoichiometric parameters α and β can have arbitrary values to achieve the aforementioned advantages, and the performance is even better for 1 m of Y 3 Al 5 O 12 if α=0.25 and α=0.5. The crystal lattice of the substrate of phosphor powder is a cubic crystal system, and the compounds BaAl 2 O 4 and Y 3 Al 5 O 12 are activated by Eu +2 and/or Ce +3 respectively and dissoved to produce a fluorescent substance.
[0036] If the stoichiometric parameters α=1 and β≦0.1, a phosphor powder with the chemical formula BaY 0.3 Al 2.5 O 52 will be formed and activated by duad rare earth element ions Eu + 2 and Sm +2 to produce a narrow band bluish green color light in the spectrum, and the half width ≦λ 0.5 =60˜70 nm. The substrate of phosphor powder has an orthorhombic crystal structure. After a blue color light with λ=460 nm is activated by the heterostructure, a strong bluish green color light with chromaticity coordinates x=0.17˜0.22 and y=0.45-0.55 is emitted.
[0037] Besides the traditional activator of Ce +3 , the Ti +3 and Fe +3 can be dissolved in a substrate of phosphor powder, such that the radiation peak value of phosphor powder can be increased to 125˜130 nm, the chromaticity coordinates of x≦0.40 and y≦0.45 feature a reddish orange color.
[0038] If BaAl 2 O 4 with a stoichiometric parameter α≦1 is added to the substrate of phosphor powder, the solid solution cyrstal has the structure of an orthorhomic crystal system. Therefore Gd +3 can be used to substitute the portion of y +3 , and the radiation peak value of phosphor powder shifts towards a long wave having a band from λ=558 nm to λ≦570 nm. The summation of chromaticity coordinates of the emitted light is Σ(x+y)≧0.80. A sample of this phosphor powder shows an advantage of emitting red color light at a high temperature.
[0039] The stoichiometric parameters α and β vary within the range of α/β≧2, so that the color of the syntheized phosphor powder will be darkened. If α=1 and β=1, the phosphor powder will show a light yellow color, which is close to a yellow color of grass, and the value of α will be increased to change the color to a gold color. The miniumum radiation absorbed by the phosphor powder shows up at the band with λ=440˜480 nm, and the maximum light reflection at a band with λ≧560 nm can be up to R=90%˜95%.
[0040] As mentioned in the previous section, Sr +2 or Ca +2 can be used to substitute the portion of Ba +2 in a cation sub crystal lattice. The substrate of phosphor powder can be activated by Eu +2 , Sm +2 or Mn +2 to produce a narrow band radiation with Δλ=100˜110 nm at a band of 505 nm˜585 nm in the spectrum.
[0041] In the present invention, the features of lights emitted by the phosphor powder are studied. If the stoichiometric parameters α=1 and β≦0.5, the afterglow of the light emitted by the phosphor powder will be t e =100˜150 ns, and if β/α≧4, the afterglow will be decreased to t=40˜50 ns.
[0042] There are many solutions for synthezing this kind of phosphor powder in accordance with the invention. Referring to FIG. 1 for the flow chart of a method of producing phosphor powder in accordance with a preferred embodiment of the present invention, the method comprises the steps of: performing a solid phase sintering for oxides and carbonates (Step 1 ); continuing the solid phase sintering at a high temperature environment for several hours (Step 2 ); and performing an ignition in the reduction environment at a high temperature (Step 3 ).
[0043] In Step 1 , a solid phase sintering is performed for the oxides and carbonate, wherien the oxides include Y 2 O 3 , Al 2 O 3 and Ce 2 O 3 , and the carbonate is BaCO 3 .
[0044] In Step 2 , the solid phase sintering is continued for several hours in a high temperature environment, wherein the high temperature environment is from 1100° C. to 1500° C. and the sintering is continued for 2˜10 hours.
[0045] In Step 3 , an ignition is performed at a high temperature in a reduction environment, wherein the reduction environment is conducted at H 2 :N 2 =1:20.
[0046] Referring to FIG. 2 for the flow chart of a method of producing phosphor powder in accordance with another preferred embodiment of the present invention, the method comprises the steps of: using hydroxides as raw materials (Step 1 ); and adding the hydroxides with an appropriate proportion into a melted barium hydroxide and mixing the hydroxides (Step 2 ).
[0047] In Step 1 , hydroxides are used as raw materials, wherein the hydroxides include Ba(OH) 2 .8H 2 O, Sr(OH) 2 .8H 2 O, Al(OH) 3 and Y(OH) 3 , etc.
[0048] In Step 2 , the hydroxides with an appropriate proportion is added into the melted barium hydroxide and mixed thoroughly, wherien the phosphor powders produced by such chemical melting method show a solid solution form and achive a higher parameter of a light emission of equivalent quality. Table 1 lists the parameters of the compound obtained by the melting method.
[0000]
TABLE 1
Peak
Wavelength
when
stoichiometric
Ce +3 is
parameter
Crystal Lattice Structure
initiated
α
B
Types
(nm)
x, y
1
1.0
0.1
orthorhomic crystal
530
0.29, 0.32
system
2
1.0
0.25
hexagonal crystal system
540–55-
0.35, 0.39
3
1.0
0.5
hexagonal crystal system
545–560
0.36, 0.42
4
1.0
1.0
monoclinic crystal
560–570
0.38, 0.42
system
5
0.75
1.0
hexagonal crystal system
540–560
0.34, 0.38
6
0.5
1.0
Pseudo-cubic crystal
535–585
0.30, 0.45
system
7
0.25
1.0
Cubic crystal system
545–585
0.38, 0.44
8
0.1
1.0
cubic crystal system
550–560
0.36, 0.42
9
2.0
1.0
orthorhomic crystal
545–575
0.33, 0.43
system
10
0.10
4.0
cubic crystal system
535–575
0.30, 0.45
[0049] The phosphor powder particles produced in the melting method is substantially in a sheet form, and the change of particles is shown in its linear dimension of a plane (1 μ˜20 μ), and the change of thickness (1.5 μ˜2 μ) is not large. The structure of these sheet type phosphor powder particles can be used for making the enhanced light transfer apparatus. This apparatus is made by filling the phosphor powder particles into the polymer films. The degree of polymerization is equal to 100˜500, and an epoxy resin or an organosilicon resin with a molecule quality of 5000˜10000 is used as a membrane material. The molecule quality of polymer is too large, and thus it cannot dissipate the heat produced during the operation of the light emitting diode. The phosphor powder particles filled in the enhanced light transfer structure has a concentration of 1%˜50%, and the most approriate concentration is 15%˜25%, and all light emitting surfaces of this kind of enhanced light transfer powders in the heterostructure has a coating with an even thickness, and the geometric thickness of the coating falls within 50 μ˜200 μ and varies with the sheet phosphor powder particles. The thickness of the enhanced light tranfer layer is usually equal to 80 μ˜120 μ.
[0050] In the experiments of the inveniton, several solutions are provided for producing a white light light emitting diode, and the technical parameters are given as follows: the light emitting intensity I≧100 cd and the light emitting efficiency η≧35 lm/w. Compared with traditional garnet phosphor powders, this new phosphor powder has a wider light emitting spectrum and a higher color index R≧85, and thus it can be used extensively in light emitting diodes for professional illuminations.
[0051] In summation of the description above, the white light LED, enhanced light transfer powder, phosphor powder and a method of producing phosphor powder in accordance with the present invneiton uses a white light nitride heterostructures that can radiate several color lights, and features a strong yellow color and a yellowish orange color with a very high quantum light emitting efficiency and an enduring light emitting time, and thus the inveniton definitely can overcome the shortcomigns of the prior art white light LED and a method of producing its phosphor powder.
[0052] While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope and spirit of the invention set forth in the claims. | The invention discloses a white light LED, an enhanced light transfer powder, a phosphor powder and a method of producing phosphor powder that use a plurality of radiating color lights and include a white light nitride heterostructure. The invention provides a novel solid liquid of a luminescence material with a chemical formula Ba α Y 3β Al 2α+5β O 4α+12β , where α and β have a value ranging 0.1˜4. The crystal lattice structure of the phosphor powder varies from cubic crystal system to monoclinic crystal system accroding to the change of the ratio of α and β. It shows significant yellow color and yellowish orange color and has very high quantum light emitting efficiency and enduring light emitting time. In such novel phosphor powder base, the invention further develops an enhanced light transfer apparatus that is a blue light heterostructure emiting a raidaion with a wavelength λ=450˜475 nm and comprised of polymers and phosphor powder particles filled therein, and the concentration of phosphor powder is 1%˜50%. The novel white semiconductor source has a very high light intensity (I>100 cd) and luminous flux, and its light emitting efficiency is up to 501 m/w. | 8 |
RELATED APPLICATION DATA
[0001] This application is a continuation of copending application Ser. No. 10/113,398, filed Mar. 27, 2002, which is a continuation of application Ser. No. 09/408,878, filed Sep. 29, 1999 (now abandoned), which is a continuation of application Ser. No. 09/317,784, filed May 24, 1999 (now U.S. Pat. No. 6,072,888), which is a continuation of application Ser. No. 09/074,632, filed May 7, 1998 (now U.S. Pat. No. 5,930,377), which is a continuation of application Ser. No. 08/969,072, filed Nov. 12, 1997 (now U.S. Pat. No. 5,809,160), which is a continuation of application Ser. No. 07/923,841, filed Jul. 31, 1992 (now U.S. Pat. No. 5,721,788).
TECHNICAL FIELD
[0002] The invention relates to a method of and system for processing a digital image to encode information therein, and to subsequently determine if an image was derived from the encoded image.
BACKGROUND OF THE INVENTION
[0003] Various images in traditional print or photographic media are commonly distributed to many users. Examples include the distribution of prints of paintings to the general public and photographs and film clips to and among the media. Owners may wish to audit usage of their images in print and electronic media, and so require a method to analyze print, film and digital images to determine if they were obtained directly from the owners or derived from their images. For example, the owner of an image may desire to limit access or use of the image. To monitor and enforce such a limitation, it would be beneficial to have a method of verifying that a subject image is copied or derived from the owner's image. The method of proof should be accurate and incapable of being circumvented. Further, the method should be able to detect unauthorized copies that have been resized, rotated, cropped, or otherwise altered slightly.
[0004] In the computer field, digital signatures have been applied to non-image digital data in order to identify the origin of the data. For various reasons these prior art digital signatures have not been applied to digital image data. One reason is that these prior art digital signatures are lost if the data to which they are applied are modified. Digital images are often modified each time they are printed, scanned, copied, or photographed due to unintentional “noise” created by the mechanical reproduction equipment used. Further, it is often desired to resize, rotate, crop or otherwise intentionally modify the image. Accordingly, the existing digital signatures are unacceptable for use with digital images.
SUMMARY OF THE INVENTION
[0005] The invention includes a method and system for embedding image signatures within visual images, applicable in the preferred embodiments described herein to digital representations as well as other media such as print or film. The signatures identify the source or ownership of images and distinguish between different copies of a single image.
[0006] In a preferred embodiment described herein, a plurality of signature points are selected that are positioned within an original image having pixels with pixel values. The pixel values of the signature points are adjusted by an amount detectable by a digital scanner. The adjusted signature points form a digital signature that is stored for future identification of subject images derived from the image.
[0007] The foregoing and other features 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
[0008] FIG. 1 is a diagram of a computer system used in a preferred embodiment of the present invention.
[0009] FIG. 2 is a sample digital image upon which a preferred embodiment of the present invention is employed.
[0010] FIG. 3 is a representation of a digital image in the form of an array of pixels with pixel values.
[0011] FIG. 4 is graphical representation of pixel values showing relative minima and maxima pixel values.
[0012] FIG. 5 is a digital subject image that is compared to the image of FIG. 2 according to a preferred embodiment of the present invention.
DETAILED DESCRIPTION
[0013] The present invention includes a method and system for embedding a signature into an original image to create a signed image. A preferred embodiment includes selecting a large number of candidate points in the original image and selecting a number of signature points from among the candidate points. The signature points are altered slightly to form the signature. The signature points are stored for later use in auditing a subject image to determine whether the subject image is derived from the signed image.
[0014] The signatures are encoded in the visible domain of the image and so become part of the image and cannot be detected or removed without prior knowledge of the signature. A key point is that while the changes manifested by the signature are too slight to be visible to the human eye, they are easily and consistently recognizable by a common digital image scanner, after which the signature is extracted, interpreted and verified by a software algorithm.
[0015] In contrast to prior art signature methods used on non-image data, the signatures persist through significant image transformations that preserve the visible image but may completely change the digital data. The specific transforms allowed include resizing the image larger or smaller, rotating the image, uniformly adjusting color, brightness and/or contrast, and limited cropping. Significantly, the signatures persist through the process of printing the image to paper or film and rescanning it into digital form.
[0016] Shown in FIG. 1 is a computer system 10 that is used to carry out an embodiment of the present invention. The computer system 10 includes a computer 12 having the usual complement of memory and logic circuits, a display monitor 14 , a keyboard 16 , and a mouse 18 or other pointing device. The computer system also includes a digital scanner 20 that is used to create a digital image representative of an original image such as a photograph or painting. Typically, delicate images, such as paintings, are converted to print or film before being scanned into digital form. In one embodiment a printer 22 is connected to the computer 12 to print digital images output from the processor. In addition, digital images can be output in a data format to a storage medium 23 such as a floppy disk for displaying later at a remote site. Any digital display device may be used, such a common computer printer, X-Y plotter, or a display screen.
[0017] An example of the output of the scanner 20 to the computer 12 is a digital image 24 shown in FIG. 2 . More accurately, the scanner outputs data representative of the digital image and the computer causes the digital image 24 to be displayed on the display monitor 14 . As used herein “digital image” refers to the digital data representative of the digital image, the digital image displayed on the monitor or other display screen, and the digital image printed by the printer 22 or a remote printer.
[0018] The digital image 24 is depicted using numerous pixels 24 having various pixel values. In the gray-scale image 24 the pixel values are luminance values representing a brightness level varying from black to white. In a color image the pixels have color values and luminance values, both of which being pixel values. The color values can include the values of any components in a representation of the color by a vector. FIG. 3 shows digital image 24 A in the form of an array of pixels 26 . Each pixel is associated with one or more pixel values, which in the example shown in FIG. 3 are luminance values from 0 to 15.
[0019] The digital image 24 shown in FIG. 2 includes thousands of pixels. The digital image 24 A represented in FIG. 3 includes 225 pixels. The invention preferably is used for images having pixels numbering in the millions. Therefore, the description herein is necessarily a simplistic discussion of the utility of the invention.
[0020] According to a preferred embodiment of the invention numerous candidate points are located within the original image. Signature points are selected from among the candidate points and are altered to form a signature. The signature is a pattern of any number of signature points. In a preferred embodiment, the signature is a binary number between 16 and 32 bits in length. The signature points may be anywhere within an image, but are preferably chosen to be as inconspicuous as possible. Preferably, the number of signature points is much greater than the number of bits in a signature. This allows the signature to be redundantly encoded in the image. Using a 16 to 32 bit signature, 50-200 signature points are preferable to obtain multiple signatures for the image.
[0021] A preferred embodiment of the invention locates candidate points by finding relative maxima and minima, collectively referred to as extrema, in the image. The extrema represent local extremes of luminance or color. FIG. 4 shows what is meant by relative extrema. FIG. 4 is a graphical representation of the pixel values of a small portion of a digital image. The vertical axis of the graph shows pixel values while the horizontal axis shows pixel positions along a single line of the digital image. Small undulations in pixel values, indicated at 32 , represent portions of the digital image where only small changes in luminance or color occur between pixels. A relative maximum 34 represents a pixel that has the highest pixel value for a given area of the image. Similarly, a relative minimum 36 represents a pixel that has the lowest pixel value for a given area of the image.
[0022] Relative extrema are preferred signature points for two major reasons. First, they are easily located by simple, well known processing. Second, they allow signature points to be encoded very inconspicuously.
[0023] One of the simplest methods to determine relative extrema is to use a “Difference of Averages” technique. This technique employs predetermined neighborhoods around each pixel 26 ; a small neighborhood 28 and a large neighborhood 30 , as shown in FIGS. 2 and 3 . In the present example the neighborhoods are square for simplicity, but a preferred embodiment employs circular neighborhoods. The technique determines the difference between the average pixel value in the small neighborhood and the average pixel value of the large neighborhood. If the difference is large compared to the difference for surrounding pixels then the first pixel value is a relative maxima or minima.
[0024] Using the image of FIG. 3 as an example, the Difference of Averages for the pixel 26 A is determines as follows. The pixel values within the 3.times0.3 pixel small neighborhood 28 A add up to 69; dividing by 9 pixels gives an average of 7.67. The pixel values within the 5.times0.5 pixel large neighborhood 30 A add up to 219; dividing by 25 pixels gives an average of 8.76 and a Difference of Averages of −1.09. Similarly, the average in small neighborhood 28 G is 10.0; the average in large neighborhood 30 G is 9.8; the Difference of Averages for pixel 26 G is therefore 0.2. Similar computations on pixels 26 B- 26 F produce the following table:
26A 26B 26C 26D 26E 26F 26G Small Neighborhood 7.67 10.56 12.89 14.11 13.11 11.56 10.0 Large Neighborhood 8.76 10.56 12.0 12.52 12.52 11.36 9.8 Difference of −1.09 0.0 0.89 1.59 0.59 0.2 0.2 Averages
[0025] Based on pixels 26 A- 26 G, there may be a relative maximum at pixel 26 D, whose Difference of Averages of 1.59 is greater than the Difference of Averages for the other examined pixels in the row. To determine whether pixel 26 D is a relative maximum rather than merely a small undulation, its Difference of Averages must be compared with the Difference of Averages for the pixels surrounding it in a larger area.
[0026] Preferably, extrema within 10% of the image size of any side are not used as signature points. This protects against loss of signature points caused by the practice of cropping the border area of an image. It is also preferable that relative extrema that are randomly and widely spaced are used rather than those that appear in regular patterns.
[0027] Using the Difference of Averages technique or other known techniques, a large number of extrema are obtained, the number depending on the pixel density and contrast of the image.
[0028] Of the total number of extrema found, a preferred embodiment chooses 50 to 200 signature points. This may be done manually by a user choosing with the keyboard 16 , mouse 18 , or other pointing device each signature point from among the extrema displayed on the display monitor 14 . The extrema may be displayed as a digital image with each point chosen by using the mouse or other pointing device to point to a pixel or they may be displayed as a list of coordinates which are chosen by keyboard, mouse, or other pointing device. Alternatively, the computer 12 can be programmed to choose signature points randomly or according to a preprogrammed pattern.
[0029] One bit of binary data is encoded in each signature point in the image by adjusting the pixel values at and surrounding the point. The image is modified by making a small, preferably 2%-10% positive or negative adjustment in the pixel value at the exact signature point, to represent a binary zero or one. The pixels surrounding each signature point, in approximately a 5.times0.5 to 10.times0.10 grid, are preferably adjusted proportionally to ensure a continuous transition to the new value at the signature point. A number of bits are encoded in the signature points to form a pattern which is the signature for the image.
[0030] In a preferred embodiment, the signature is a pattern of all of the signature points. When auditing a subject image, if a statistically significant number of potential signature points in the subject image match corresponding signature points in the signed image, then the subject image is deemed to be derived from the signed image. A statistically significant number is somewhat less than 100%, but enough to be reasonably confident that the subject image was derived from the signed image.
[0031] In an alternate embodiment, the signature is encoded using a redundant pattern that distributes it among the signature points in a manner that can be reliably retrieved using only a subset of the points. One embodiment simply encodes a predetermined number of exact duplicates of the signature. Other redundant representation methods, such as an error-correcting code, may also be used.
[0032] In order to allow future auditing of images to determine whether they match the signed image, the signature is stored in a database in which it is associated with the original image. The signature can be stored by associating the bit value of each signature point together with x-y coordinates of the signature point. The signature may be stored separately or as part of the signed image. The signed image is then distributed in digital form.
[0033] As discussed above, the signed image may be transformed and manipulated to form a derived image. The derived image is derived from the signed image by various transformations, such as resizing, rotating, adjusting color, brightness and/or contrast, cropping and converting to print or film. The derivation may take place in multiple steps or processes or may simply be the copying of the signed image directly.
[0034] It is assumed that derivations of these images that an owner wishes to track include only applications which substantially preserve the resolution and general quality of the image. While a size reduction by 90%, a significant color alteration or distinct-pixel-value reduction may destroy the signature, they also reduce the image's significance and value such that no auditing is desired.
[0035] In order to audit a subject image according to a preferred embodiment, a user identifies the original image of which the subject image is suspected of being a duplicate. For a print or film image, the subject image is scanned to create a digital image file. For a digital image, no scanning is necessary. The subject digital image is normalized using techniques as described below to the same size, and same overall brightness, contrast and color profile as the unmodified original image. The subject image is analyzed by the method described below to extract the signature, if present, and compare it to any signatures stored for that image.
[0036] The normalization process involves a sequence of steps to undo transformations previously made to the subject image, to return it as close as possible to the resolution and appearance of the original image. It is assumed that the subject image has been manipulated and transformed as described above. To align the subject image with the original image, a preferred embodiment chooses three or more points from the subject image which correspond to points in the original image. The three or more points of the subject image are aligned with the corresponding points in the original image. The points of the subject image not selected are rotated and resized as necessary to accommodate the alignment of the points selected.
[0037] For example, FIG. 5 shows a digital subject image 38 that is smaller than the original image 24 shown in FIG. 2 . To resize the subject image, a user points to three points such as the mouth 40 B, ear 42 B and eye 44 B of the subject image using the mouse 18 or other pointer. Since it is usually difficult to accurately point to a single pixel, the computer selects the nearest extrema to the pixel pointed to by the user. The user points to the mouth 40 A, ear 42 A, and eye 44 A of the original image. The computer 12 resizes and rotates the subject image as necessary to ensure that points 40 B, 42 B, and 44 B are positioned with respect to each other in the same way that points 40 A, 42 A, and 44 A are positioned with respect, to each other in the original image. The remaining pixels are repositioned in proportion to the repositioning of points 40 B, 42 B and 44 B. By aligning three points the entire subject image is aligned with the original image without having to align each pixel independently.
[0038] After the subject image is aligned, the next step is to normalize the brightness, contrast and/or color of the subject image. Normalizing involves adjusting pixel values of the subject image to match the value-distribution profile of the original image. This is accomplished by a technique analogous to that used to align the subject image. A subset of the pixels in the subject image are adjusted to equal corresponding pixels in the original image. The pixels not in the subset are adjusted in proportion to the adjustments made to the pixels in the subset. The pixels of the subject image corresponding to the signature points should not be among the pixels in the subset. Otherwise any signature points in the subject image will be hidden from detection when they are adjusted to equal corresponding pixels in the original image.
[0039] In a preferred embodiment, the subset includes the brightest and darkest pixels of the subject image. These pixels are adjusted to have luminance values equal to the luminance values of corresponding pixels in the original image. To ensure that any signature points can be detected, no signature points should be selected during the signature embedding process described above that are among the brightest and darkest pixels of the original image. For example, one could use pixels among the brightest and darkest 3% for the adjusting subset, after selecting signature points among less than the brightest and darkest 5% to ensure that there is no overlap.
[0040] When the subject image is fully normalized, it is preferably compared to the original image. One way to compare images is to subtract one image from the other. The result of the subtraction is a digital image that includes any signature points that were present in the subject image. These signature points, if any, are compared to the stored signature points for the signed image. If the signature points do not match, then the subject image is not an image derived from the signed image, unless the subject image was changed substantially from the signed image.
[0041] In an alternative embodiment, the normalized subject image is compared directly with the signed image instead of subtracting the subject image from the original image. This comparison involves subtracting the subject image from the signed image. If there is little or no image resulting from the subtraction, then the subject image equals to the signed image, and therefore has been derived from the signed image.
[0042] In another alternate embodiment, instead of normalizing the entire subject image, only a section of the subject image surrounding each potential signature point is normalized to be of the same general resolution and appearance as a corresponding section of the original image. This is accomplished by selecting each potential signature point of the subject image and selecting sections surrounding each potential signature point. The normalization of each selected section proceeds according to methods similar to those disclosed above for normalizing the entire subject image.
[0043] Normalizing each selected section individually allows each potential signature point of the subject image to be compared directly with a corresponding signature point of the signed image. Preferably, an average is computed for each potential signature point by averaging the pixel value of the potential signature point with the pixel values of a plurality of pixels surrounding the potential signature point. The average computed for each signature is compared directly with a corresponding signature point of the signed image.
[0044] While the methods of normalizing and extracting a signature from a subject image as described above are directed to luminance values, similar methods may be used for color values. Instead of or in addition to normalizing by altering luminance values, the color values of the subject image can also be adjusted to equal corresponding color values in an original color image. However, it is not necessary to adjust color values in order to encode a signature in or extract a signature from a color image. Color images use pixels having pixel values that include luminance values and color values. A digital signature can be encoded in any pixel values regardless of whether the pixel values are luminance values, color values, or any other type of pixel values. Luminance values are preferred because alterations may be made more easily to luminance values without the alterations being visible to the human eye.
[0045] From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims. | A digital image is processed to hide information, by generally inconspicuous adjustments thereof. These adjustments can define a pattern that extends across some or all of the image. Desirably, the pattern is adapted to the particular image being encoded, so as to better conceal the encoding. | 7 |
This application is a continuation of application Ser. No. 07/899,039, filed on Jun. 16, 1992, now abandoned, which is a continuation of application Ser. No. 07/630,490, filed Dec. 20, 1990, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a recording apparatus, and more specifically to a recording apparatus which can use various kinds of recording sheets.
2. Related Background Art
Known recording apparatus use sheets of a plurality of sizes as recording media. For example, copying machines have been developed which permit an operator to select or exchange copying sheets in accordance with the size of an original to be copied. Such known copying machines can have plural sheet feeding units, storing copy sheets of different sizes. These machines select a copy sheet of a certain size to be fed through the machine based on the size of an original which is sensed by a sensor or based on a desired enlargement/reduction factor. As another example, known page printers permit an operator to exchange sheets or select a feeding unit storing a sheet of a designated size according to a sheet size designation accompanying printing data. However, these known recording apparatus control only the size of the recording medium. As a result, such recording apparatus cannot respond to a request for the use of various kinds of sheets for recording. Such sheets include, for example, perforated paper, pre-printed paper on which a prescribed form is printed, multi-hole paper, color paper, and paper having an adhesive backing. Thus, data to be printed on plain paper may be printed on pre-printed paper when an operator who inputs printing data does not observe the recording apparatus.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a recording apparatus that can overcome the problems described above.
It is another object of the present invention to provide a recording apparatus that can execute an appropriate recording operation on different kinds of paper.
It is still another object of the present invention to provide a recording apparatus that can prevent the unnecessary consumption of recording sheets.
It is still another object of the present invention to provide a recording apparatus that performs a proper operation without being affected by the kind of a recording sheet used.
It is still another object of the present invention to provide a recording apparatus that can prevent an unnecessary charge to an operator for printing performed on the wrong paper.
In accordance with one aspect, the present invention which achieves these objectives relates to a recording apparatus comprising discrimination means for discriminating the kind of sheet on which recording is to occur specified in input data inputted into the apparatus, a memory for storing data representing the kind the sheet set in the apparatus, and control means for controlling the apparatus based on the outputs of the discrimination means and the memory. The apparatus can further comprise informing means for informing an operator of the kind of sheets specified in the input data when the kind sheets specified is different from the kind of sheet set in the apparatus. The apparatus can also comprise size discrimination means for discriminating the size of the sheet on which recording is to occur specified in the input data, and a detector for detecting the size of the sheet set in the apparatus. The control means controls the apparatus based on the outputs from the size discrimination means and the detector. The apparatus can further comprise input means for inputting the input data. The input data can include a command sent from an external device. The apparatus can also include a printing mechanism for printing an image in accordance with the input data. The discrimination means discriminates the kind of sheet specified based on the command input by the input means and can comprise a memory for storing the data representing the kind of sheets specified.
According to another aspect, the present invention relates to a recording apparatus comprising a first memory for storing data representing the kind of sheet on which recording is to occur as specified by input data inputted into the apparatus, a second memory for storing data representing the kind of sheet set in the apparatus, and informing means for informing an operator of an inconsistency between the data stored in the first and second memories. The apparatus can further comprise a third memory for storing data representing the size of the sheet specified by the input data, and a detector for detecting the size of the sheet set in the apparatus. The informing means informs an operator of an inconsistency between the data stored in the third memory and the size of the sheet detected by the detector. The apparatus also comprises input means for inputting the input data, where the input data includes a command sent from an external device, and a printing mechanism for printing an image in accordance with the input data. The printing mechanism can comprise first and second sheet feeding mechanisms. The recording apparatus can further comprise changing means for changing the sheet feeding mechanism which feeds a sheet to the printing mechanism when data stored in the first and second memories are inconsistent.
Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred embodiment of the present invention and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the structure of a recording apparatus according to a first preferred embodiment of the present invention;
FIG. 2 is a flow chart for explaining a printing control procedure according to the embodiment shown in FIG. 1;
FIG. 3 is a block diagram showing the structure of a recording apparatus according to a second preferred embodiment of the present invention; and
FIG. 4 is a flow chart for explaining a printing control procedure according to the embodiment shown in FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiments of the present invention will be described in detail herein with reference to the accompanying drawings.
Embodiment 1
FIG. 1 is a block diagram showing the structure of a recording apparatus according to a first embodiment of the present invention. The apparatus shown in FIG. 1 includes a central processing unit (CPU) 1 for controlling the entire printing operation, including image processing, of the recording apparatus, and an input port 2 for receiving input data sent from a host device (not shown) and for providing the CPU 1 with received input data.
A printing mechanism 3 includes a sheet feeding mechanism 12, and a detecting means 12-1 for detecting the size of a sheet, which is set in the sheet feeding mechanism 12 as a recording medium. The printing mechanism 12 prints a bit image of input data on a sheet by using a known electrophotographic technology.
A console 4 is provided for displaying a message sent from the recording apparatus for an operator, and for providing the recording apparatus with instructions from an operator. An input sheet kind register 5 is also provided for storing the kind of sheet designated by a sheet designation command, which is included in input data received by the input port 2. An input sheet size register 6 is provided for storing a sheet size designated by the sheet designation command. Also provided is a printing sheet kind register 7 for storing the kind of a sheet set in the sheet feeding mechanism 12 of the printing mechanism 3. The operator inputs data into the printing sheet kind register 7 through console 4 to determine the type of sheet the operator desires to be set by the apparatus. This is done before the CPU 1 compares the contents of the input sheet kind register 5 and the printing sheet kind register 7.
In FIG. 1, the thick arrows show the flow of printing data, and the thin arrows show the flow of control information.
An explanation of a printing procedure according to the first embodiment will now be provided below with reference to a flow chart shown in FIG. 2.
In FIG. 2, steps 1 to 7 denote each procedure, and each procedure is stored in a program memory (not shown).
Before printing, the CPU 1 sets the kind of sheet in the input sheet kind register 5, and the sets the sheet size in the input sheet size register 6, in accordance with a designation by a sheet designation command, which is included in input data sent from the host device (not shown).
In step 1, the CPU 1 compares the contents of the printing sheet kind register 7 with the contents of the input sheet kind register 5, and checks whether the kind of a sheet set in the sheet feeding mechanism 12 is the same as the kind of the sheet designated by the sheet designation command. If it is, the flow advances to step 2, where the CPU 1 compares the sheet size detected by the printing mechanism 3 with the content of the input sheet size register 6, and checks whether the size of the sheet set in the sheet feeding mechanism 12 is the same as the sheet size designated by the sheet designation command. If it is, the flow advances to step 3, where the CPU 1 sets the content of the input sheet kind register 5 in the printing sheet kind register 7. Then, in step 4, the CPU 1 analyzes input data, and causes one page to be printed by the printing mechanism 3.
In step 5, the CPU 1 checks whether the printing of the entire data is completed. When in step 5 the printing is not completed, the flow returns to step 1, where the printing is continued. If the answer in step 5 is yes, the printing is terminated.
If in steps 1 or 2 the answer is no, i.e., when the kind or size of the sheet set in the sheet feeding mechanism 12 are different from the kind or size of the sheet designated by the sheet designation command, the flow advances to step 6.
In step 6, a message for requesting an operator to change the sheet is displayed on the console 4. Then, in step 7, the CPU stands by to wait for a printing restart instruction input by an operator through the console 4. When in step 7 the printing restart instruction is input, the flow returns to step 2, where the CPU 1 checks the size of the sheet set in the sheet feeding mechanism 12 again.
According to the recording apparatus of the first embodiment, in the case where the sheet designated by input data is different from the sheet set in the sheet feeding mechanism 12, this fact is detected in step 1 or step 2 in FIG. 2, so that an operator is called. If the operator sets the designated sheet in the sheet feeding mechanism 12 and inputs the printing restart instruction, the recording apparatus checks only whether the size of the sheet in the apparatus is the same as the designated sheet size in step 2. If the sheet size is the same as designated sheet size, the CPU 1 determines that a correct sheet has been set. Then, in step 3, the CPU 1 renews the content of the printing sheet kind register 7 to execute a printing operation.
It should be noted that the CPU 1 checks only the size of the sheet set in the sheet feeding mechanism 12 after the printing restart instruction is input, and renews the contents of the printing sheet kind register 7 after checking the sheet size. Because there are many kinds of sheets, it is impossible for the printing mechanism to detect every type of sheet. For example, if the printing mechanism could detect multi-holed paper, it may be difficult to detect perforated paper. In addition, even if pre-printed paper could be detected, it would be extremely difficult to discriminate the type of preprinted paper. In addition, printing mechanisms cannot detect paper having an adhesive backing, colored paper, a transparent sheet for an overhead projector, or the like. As a result, the judgment of the operator is always required. The present invention permits the judgment of the operator to be exercised by permitting the operator to determine the type of sheet the operator desires to be set by the apparatus by inputting such data into the sheet kind register 7 through console 4. In addition, when the kind of sheet set in the sheet feeding mechanism 12 is different from the sheet designated by the sheet designation command, a message requesting the operator to change the sheet is displayed on the console 4.
By executing the above-described control, it is possible to prevent paper of different kinds from being printed together when this is not the operator's intention. Further, the apparatus can be adapted to various kinds of sheets.
Embodiment 2
FIG. 3 is a block diagram showing the structure of a recording apparatus according to a second embodiment of the present invention.
According to the second embodiment, the printing mechanism 3 shown in FIG. 1 is newly structured as a printing mechanism 3a having two sheet feeding mechanisms I, II (12a), and registers 8, 9, 11 and a counter 10 for controlling each sheet feeding mechanism. In FIG. 3, the same reference numerals are used to denote the corresponding elements shown in FIG. 1.
The apparatus shown in FIG. 3 includes a CPU 1a for conducting the entire printing control, including image processing, of the recording apparatus, and an input port 2 for receiving input data sent from a host device (not shown) and for providing the CPU 1a with the received input data. The printing mechanism 3a includes the two sheet feeding mechanisms I, II (12a), and detecting means 12a-1, 12a-2 for detecting the size of sheets, which are set in the sheet feeding mechanisms I, II, respectively. The printing mechanism 3a prints a dot image of input data on a sheet.
A console 4 is provided for displaying a message sent from the recording apparatus for an operator, and for providing recording apparatus instructions from an operator. An input sheet kind register 5 is also provided for storing the kind of sheet designated by a sheet designation command, which is included in input data received by the input port 2. An input sheet size register 6 is provided for storing a sheet size designated by the sheet designation command. Also provided are printing sheet kind registers 7a, 8 for storing the kind of sheet set in the sheet feeding mechanisms I, II, respectively. A sheet feeding register 9 is provided for indicting the sheet feeding mechanism which is currently selected in the printing mechanism 3a.
The recording apparatus also includes a sheet feeding counter 10 for counting the number of times the apparatus changes the sheet feeding mechanism which is used and a sheet feeding mode register 11 for storing a sheet feeding mode.
In FIG. 3, the thick arrows show the flow of printing data, and the thin arrows show the flow of control information.
An AUTO mode and a MANUAL mode are included as sheet feeding modes. In the AUTO mode, the sheet feeding mechanisms are changed automatically to use a sheet designated by input data according to the presence of a sheet in the sheet feeding mechanism, the kind of a sheet, the sheet size, or the like. In the MANUAL mode, the sheet feeding mechanism to be used is designated by input data or the console 4.
An explanation of a printing procedure according to the second embodiment will be provided below with reference to a flow chart shown in FIG. 4.
FIG. 4 is a flow chart for showing a series of printing procedures according to the second embodiment. In FIG. 4, steps 11 to 28 denote each procedure to be performed, and each procedure is stored in a program memory (not shown). In FIG. 4, steps for controlling the plural sheet feeding mechanisms are added to the flow chart shown in FIG. 2, whereby steps 15 to 19 in FIG. 4 correspond to steps 1 to 5 in FIG. 2 and steps 24 and 25 in FIG. 4 correspond to steps 6 and 7 in FIG. 2.
Before printing, the CPU 1a sets the kind of sheet in the input sheet kind register 5, and sets the sheet size in the input sheet size register 6, in accordance with a designation by a sheet designation command, which is included in input data sent from the host device (not shown).
In step 11, the CPU 1a initializes the sheet feeding counter 10. Then, in step 12, the CPU 1a checks for the presence of the sheet designation command by analyzing input data. When in step 12 there is no sheet designation command, the flow advances to step 14 by skipping step 13. If in step 12 the answer is yes, the CPU 1a sets the kind of sheet in the input sheet kind register 5, and sets the sheet size in the input sheet size register 6, in accordance with the sheet designation command in step 13.
Then, in step 14, the CPU 1a checks the current sheet feeding mode using the contents of the sheet feeding mode register 11.
If the current sheet feeding mode is the MANUAL mode, the flow advances to steps 27, 28, where sheet feeding mechanism designation/changing processing is performed. If the current sheet feeding mode is the AUTO mode, the flow advances to step 15 by skipping steps 27, 28.
In step 15, the CPU 1a compares the contents of the printing sheet kind register designated by the sheet feeding register 9 with the contents of the input sheet kind register 5, and checks whether the kind of sheet set in the sheet feeding mechanism currently selected is the same as the kind of the sheet designated by the sheet designation command. If it is, the flow advances to step 16, where the CPU 1a compares the sheet size detected by the sheet feeding mechanism, which is designated by the sheet feeding register 9, with the contents of the input sheet size register 6, and checks whether the size of the sheet set in the sheet feeding mechanism currently selected is the same as the sheet size designated by the sheet designation command. If it is, the flow advances to step 17, where the CPU 1a sets the contents of the input sheet kind register 5 in the printing sheet kind register, which is designated by the sheet feeding register 9. Then, in step 18, the CPU 1a analyzes input data, and causes one page to be printed by the printing mechanism 3a.
In step 19, the CPU 1a checks whether the printing of the entire data is completed. When in step 19 the printing is not completed, the flow returns to step 11, where the printing is continued. If the answer in step 19 is yes, the printing is terminated.
When in steps 15 or 16 the answer is no, i.e., when the kind or size of the sheet set in the sheet feeding mechanism currently selected are different from the kind or size of the sheet designated by the sheet designation command, the flow advances to step 20. In step 20, the CPU 1a checks the current sheet feeding mode using the contents of the sheet feeding mode register 9. If the current sheet feeding mode is the AUTO mode, the flow advances to steps 21 through 23, where sheet feeding mechanism automatic changing processing is performed. If the current sheet feeding mode is the MANUAL mode, the flow advances to step 24 by skipping steps 21 to 23.
In step 21, the CPU 1a renews the sheet feeding mechanism to be selected, i.e., instructs the printing mechanism 3a to change the sheet feeding mechanism, which is used to feed sheets to the printing mechanism 3a and changes the contents of the sheet feeding register 9 so that register 9 stores data representing the other sheet feeding mechanism. Then, in step 22, the CPU 1a adds "1" to the contents of the sheet feeding counter 10. In step 23, the CPU 1a checks whether the contents of the sheet feeding counter 10 has reached the number of the sheet feeding mechanisms, i.e., 2 in this embodiment. If the contents of the sheet feeding counter 10 is less than the number of the sheet feeding mechanisms, the flow advances to step 15, where the CPU 1a checks the kind of sheet set in the other sheet feeding mechanism. If the answer in step 23 is yes, the flow advances to step 24, where a message for requesting an operator to change the sheet is displayed on the console 4.
In step 25, the CPU 1a stands by to wait for a printing restart instruction input by an operator through the console 4. When in step 25 the printing restart instruction is input, the CPU 1a initializes the sheet feeding counter 10 to "0" in step 26. Then the flow returns to step 16, where the CPU 1a checks the size of the sheet set in the former sheet feeding mechanism again.
In sheet feeding mechanism designation/changing processing of step 27, the CPU 1a checks for the presence of a sheet feeding mechanism designation command by analyzing input data. When in step 27 there is the sheet feeding mechanism designation command, the CPU 1a instructs the printing mechanism 3a to designate the sheet feeding mechanism in accordance with the command, and sets the contents of the sheet feeding register 9 according to the command. Then the flow returns to step 15.
According to the second embodiment, specific types of processing are performed in accordance with the sheet feeding modes. In the case where the sheet feeding mode is the AUTO mode, sheet feeding mechanism automatic changing processing is performed in steps 21 to 23. In the case where the sheet feeding mode is the MANUAL mode, sheet feeding mechanism designation/changing processing is performed in steps 27, 28.
According to the second embodiment, the recording apparatus can be adapted to various kinds or sizes of sheets flexibly, and can prevent an undesired sheet from being printed efficiently.
In the above-described embodiment, two sheet feeding mechanisms are provided. However, if printing sheet kind registers corresponding to the number of the sheet feeding mechanisms are provided, any number of sheet feeding mechanisms, greater than one, can be provided.
In the embodiments shown in FIG. 1 and FIG. 3, the console 4 is provided as a display means for displaying a message sent from the recording apparatus for an operator and a means for providing the recording apparatus with instructions from an operator. However, it is not necessary to integrate these means. In addition, the display means can comprise any kind of means, for example, a simple liquid crystal display or an audio synthesis device. Further, a keyboard or one button can be provided as the means for providing the recording apparatus with instruction from an operator.
The individual components represented by the blocks shown in FIGS. 1 and 3 are well known in the recording art and their specific construction and operation is not critical to the operation of the invention or the best mode for carrying out the invention. Moreover, the steps illustrated in FIGS. 2 and 4 can be easily programmed into well known central processing units by persons of ordinary skill, and since such programming per se is not part of this invention, no further description thereof is deemed necessary.
Although the preferred particular embodiments of the present invention are disclosed herein for purposes of explanation, various modifications thereof, after study of this specification, will be apparent to those skilled in the art to which the invention pertains. | A recording apparatus capable of changing the kind of sheet on which printing occurs, includes a discrimination circuit for discriminating the kind of sheet on which printing is to occur specified in input data, and a memory for storing data representing the kind of sheet set in the apparatus. A control circuit then controls the apparatus based on outputs from the discrimination circuit and the memory. | 6 |
BACKGROUND OF THE INVENTION
Fracturing of well formations is a very difficult art. According to the known procedures, the formation area which may be fractured by a fracturing treatment is limited. In order that the area of fracture may be increased, the fracturing fluid used must have a viscosity low enough to permit adequate penetration through the particular formation and at the same time high enough to prevent coefficient that excessive leak-off of fracturing fluid to the formation not occur. Fracturing fluids in the past have of necessity been formulated based on compromise between low viscosity for high formation penetration and high viscosity to prevent excessive leak-off of fracturing fluid. At the same time, the fluid must be capable of delivering the sand or other particulate matter into all parts of the fracture area. In other words, the sand should not fall from suspension in the fracturing fluid or the benefits of fracturing will not be fully realized.
In addition to the requirements of high formation penetration, low fluid loss, and satisfactory sand carrying ability of the fracturing fluid for a successful well fracturing operation, other factors are important. Well formations often contain materials which are sensitive to various liquids. In particular, the swelling clays are notably affected by water. Therefore, the amount of water used in fracturing these formations should be kept at a minimum. When a large amount of fracturing fluid (liquid) is employed in well fracturing operations, problems can occur in removing a sufficient amount of water from the formation following the fracturing treatment in order to secure adequate production from the well.
According to many well fracturing procedures, control of the fracturing operation is difficult. Not only are the factors mentioned above important, but adequate control of the fracturing fluid flow into the formation, and flow back out of the formation following completion of fracturing, is also important. The propping material must also be left in proper disposition in the formation to adequately increase production flow from the formation. The fracturing fluids afforded by this invention provide these controls, and in particular the invention affords full control of bleedback to the well of the fracturing fluid after fracturing is completed.
SUMMARY OF THE INVENTION
According to the invention, foam fracturing fluids and methods for fracturing well formations using such fluids are provided which permit increased formation penetration by the fracturing fluid, which provide low leak-off of the fracturing fluid, which provide substantially zero proppant settling in the fracturing fluid, and which cause minimal formation damage. The fracturing fluids of the invention are gas-in-liquid foams characterized by a very high foam quality, that is, the ratio of gas volume to the volume of the gas plus the liquids in the fracturing fluid is very high. These foams also have low viscosity, but at the same time have low fracturing fluid coefficients so that fluid leak-off during the fracturing operation is very low. In addition, when the foams are used as carriers for a propping agent, the settling rate of the proppant in the foams is zero or nearly zero, so dropout of the proppant from the fracturing fluid does not occur. Because of the low liquid content of the foams, there is less chance of swelling clays during fracturing treatments, and less damage to formations when water is used as the liquid component of the fracturing fluid. In addition, the high gas content of the foams allows for removal of most of the liquid from the formation after the fracturing treatment is completed. This results in faster starting of production from the well, and sometime eliminates the necessity for swabbing or pressure jetting to remove remaining water and other fluids from the formation. In addition, the gas outflow from the well following a fracturing treatment can be controlled at the surface of the well, in contrast to older methods where such control was either not satisfactory or impossible.
According to the preferred embodiment of the invention, a slurry of sand in water is pumped to a pressure sufficient to enter the well and then a relatively large amount of gas, preferably nitrogen but other gases may be used, is introduced into the pressured liquid to immediately form a very stable and stiff foam at the surface adjacent the well. A surface active agent such as soap or surfactant is added to the sand-water slurry before the gas is introduced, to assist in foam formation. Other materials, such as acids, salts, gels, polymers, and friction reducing agents, may be added to the water-sand slurry before foam formation. The foam quality may be from fifty percent (50%) to ninety percent (90%), foam quality being defined as the percentage of the volume of gas at the existing temperature and pressure to the volume of gas plus the volume of water plus the volumes of other liquid components of the foam. It has been found that if the foam quality is less than about 50 percent, a water phase may form, and if the foam quality is higher than about ninety percent, a gas phase may form. The deeper the well, and the higher the down-hole well pressure, the more gas is required at the surface to generate the same quality foam, because as the gas travels down the well it is compressed and diminishes in volume and therefore the physical properties, such as the quality of the foam changes.
The fracturing fluid is delivered into the well from the surface as a foam, and the foam quality is maintained down the well to the bottom of the well and into the formation. Usually, a volume of pressured gas, water and surfactant mixed as a foam is introduced into the formation ahead of the sand bearing foam as a pad. The sand bearing fracturing fluid is introduced at high pressure into the formation in the desired amount, to create the desired fracturing area around the well. A foam flush, formed of gas, water and surfactant is usually delivered into the well following the fracturing fluid, to flush sand from the well.
It is a feature of the invention that a substantially greater area may be fractured than with other methods. The low fracturing fluid coefficient of the foam prevents substantially all leak-off of the fracturing fluid into the formation, and the low viscosity permits greater lateral penetration through the formation. The sand carrying ability of the foam is very high, all of the sand therein being carried with the foam into the formation.
After introduction of the fracturing fluid is complete, with the sand distributed throughout the fractured area, the well is shut in until the pressure stabilizes. A small amount of nitrogen, or other gas employed in making the foam, is removed at the well head to cause breaking of the foam in the well, and to lower the pressure in the formation adjacent the well bore, thus allowing the formation to heal. The well is maintained in shutin condition for a period of time, usually from about twelve hours to about twenty-four hours, to allow the formation to heal (settle) due to the overburden above the formation. After the formation has healed, the well is opened to release the gas pressure at the formation. The pressure drop of the fracturing fluid in the formation breaks the foam in the formation, and the gas leaves the formation carrying with it substantially all of the water and other fluids originally contained in the fracturing fluid. If any water remains, it can be removed by a swabbing or jetting treatment in the well. Production from the formation can usually be commenced immediately, since no well cleaning procedure is usually required.
As has been mentioned earlier, in well formations having high sensitivity to liquids, particularly to water, damage to the formations is reduced because only a small amount of water is used in the fracturing fluids, and most of it is removed. The formation damage referred to is that caused by swelling of the so-called swelling clays in the formation.
Substantially complete removal of water following the fracturing treatment occurs because of the high foam quality, that is, the large volume of gas contained in the foam. Because of the substantially complete water removal from the formation and well, production from the well starts sooner that with other methods, and swabbing or jetting procedures necessary to start production from the well are in most cases eliminated. Since the fracturing fluid is composed mainly of gas, the rate of bleed back of the fracturing fluid from the well can be satisfactorily controlled at the surface.
A principal object of the invention is to provide improved well formation fracturing methods. Another object of the invention is to provide such methods which are safe, economical, and dependable. A still further object of the invention is to provide such well fracturing methods which yield improved results, and which are capable of fracturing greater formation areas around a well, with less loss of fracturing fluid than with other methods, and with less damage to the formations.
Other objects and advantages of the invention will appear from the following detailed description of preferred embodiments, reference during the description being made to the accompanying drawings.
BRIEF DESCRIPTIONS OF THE DRAWINGS
FIG. 1 is a schematic flow diagram showing a preferred method of formation fracturing according to the invention.
FIG. 2 is a partial schematic flow diagram illustrating a step of the preferred method.
FIG. 3 is a partial schematic flow diagram illustrating another step of the preferred well fracturing treatment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing the preferred embodiments according to the invention in detail, and referring first to FIG. 1 of the drawings, the well formation fracturing fluid is prepared by mixing sand from a source 10 with water from a source 11. Sources 10 and 11 may be any suitable sources of sand and of water, having suitable properties for their intended uses. Instead of sand, other solid particulate propping material known in the art, such as glass beads, may be used. The sand or other partculate material is usually between about eight mesh and about forty mesh in size, U.S. standard sieve size.
The sand and water are delivered into a mixing device 14 which may be of any suitable type. Propeller mixers as illustrated, or mixers utilizing augers, or any other suitable form of mixer may be used. From mixer 14, the sand-water slurry is delivered by pressurizer pump 15 to high pressure fluid pump 17. Pump 17 is shown to be mounted on a truck 18, but may be supported in any other suitable manner at the well site. High pressure sand slurry is delivered from pump 17 through a conduit 19 to the well head 20. Soap or surfactant from source 22 is admixed with the sand slurry delivered from high pressure pump 17. The soap or surfactant may alternatively be admixed with the sand slurry ahead of pump 17, as indicated by dashed line 22a. Other conditioning and treating materials for the fracturing fluid, such as acids, salts, gels, polymers, friction reducing agents, or others, may be added at the water source 11 to improve the quality of the fracturing fluid.
Acids added to the fracturing fluid assist in preventing swelling of clays. Hydrochloric acid and acetic acid are frequently used for this purpose. Salts, for example potassium chloride, also prevent clay swelling. Gels, for example Guar gum, are useful for holding the sand suspended in the sand-water slurry prior to foam formation. Oil may be added to the foam-water slurry as a lubricant and to prevent clay swelling; oil may replace all of the water in the sand slurry, in which case a chemical suitable for foaming oil is used in place of the surfactant 22. Other friction reducing materials may be added to the fracturing fluid.
High pressure gas introduced through conduit 25 is admixed with the sand slurry. High pressure nitrogen gas is preferred, but other gases may be used. Substantially any gas may be used, but among the most useful are the inert gases, carbon dioxide, air, natural gas, cumbustion or flue gases, or mixtures of any of the gases mentioned. Use of nitrogen gas is preferred since it is inert and because it may readily be provided at high pressures.
Tank 28 of tank truck 29 contains liquid nitrogen, which may be readily converted to high pressure gaseous nitrogen by pumping and heating of the liquid in unit 30 of the tank truck, as is well understood by those skilled in the art. Nitrogen gas at extremely high pressures (20,000 psia) may be readily prepared in this manner. Use of other gases, while satisfactory to the process, may be more difficult and may require the use of high pressure compressors or vaporizers to obtain the gas pressures required.
The introduction of the high pressure gas at point 19a of conduit 19 immediately converts the sand slurry to a stiff stable foam. The amount of gas in the foam is expressed in terms of foam quality, which is defined as the volume of gas at the existing temperature and pressure at the well formation or reservoir at the bottom of the well, divided by the same gas volume plus the volume of the water, surfactant or soap, plus the volumes of all other liquid materials contained in the fracturing fluid, times 100, expressed as percentage. The foam quality, according to the invention, should be between 50 percent and 90 percent. The ratio of gas to liquid in the fracturing fluid may be expressed in other terms, for example, the fracturing fluids may contain from about one thousand standard cubic feet of nitrogen or other gas per barrel of water from source 11 to about twenty thousand standard cubic feet of nitrogen or other gas per barrel of water, or even higher.
Well formations are at elevated pressures, largely proportional to well depth, and the amount of gas in the foam must be greater at greater depths and reservoir pressures in order to obtain the same foam quality. The gas volume shrinks under higher pressure, while the volume of the other components of the fracturing fluid remain substantially constant regardless of pressure. Therefore, as gas volume shrinks at higher pressure, more gas is required to obtain the gas volume required for any particular foam quality percentage.
The stiff stable foam prepared in conduit 19 by gas introduction at point 19a is delivered through conduit 19 to well head 20. The well head and well conduits as shown in the drawings are schematic, and not intended to depict an actual well structure. The equipment downhole and at the top of the well may be any suitable equipment known in the art. The foam pad, the sand bearing foam prepared as heretofore described, and the foam purge, are introduced down the well usually through a production tubing or casing in the well. According to pressure and temperature conditions in the well, and according to calculations based on the area around the well to be fractured and the fracture thickness, a prescribed amount of fracturing fluid is introduced from the well into the formation through casing perforations at the formation. In the drawing, there is shown a single casing 31 and a single tubing 32, the casing 31 having perforations 33 at formation 35. The fracturing fluid in the form of the stiff stable foam previously described is introduced down through tubing 32 and/or casing 31 and out through perforations 33 into reservoir 35. The foam as introduced into the reservoir has a foam quality between fifty percent and ninety percent, as heretofore defined. Because the foam has a relatively low density compared with the densities of other fracturing fluids, and because the fracturing fluid pressure in the well at the level of the formation must exceed the formation pressure, the foam as prepared at the surface and introduced down through the well must be at a pressure which will give the required pressure downhole at the formation. Therefore, the gas introduced at point 19a must be at a sufficiently high pressure to give the required downhole pressure in excess of formation or reservoir pressure. That is why the gas delivered from conduit 25 is preferably nitrogen gas prepared as heretofore described, since such high gas pressure is easier to achieve by this method than by the use of pressured or compressed gases or air.
The fracturing fluids herein described have better fracturing fluid coefficients than most other fracturing fluids known in the art. The fracturing fluid coefficient depends not only on the characteristics of the fracturing fluid used, but also on the characteristics of the reservoir fluids and rock. A high coefficient means high fluid-loss properties. A low coefficient means low fluid-loss properties and thus a larger fracture area for a given volume and injection rate of fracturing fluid. For any specified condition of reservoir fluid characteristics and rock characteristics, the fracturing fluid coefficient depends primarily on the fracturing fluid characteristics. A higher rate of fracturing fluid injection increases fracture area, as does lengthened pumping time using a greater volume of fracturing fluid.
After the full calculated or estimated volume of foam fracturing fluid has been introduced into the formation, a small amount of gas pressure may be bled from the well to cause the foam within the well to break, leaving the well filled with gas under pressure, the formation fracture area remaining filled with foam. The well is then shut in and maintained shut in for a period of time sufficient to permit healing of the formation. By healing, it is meant that the overburden above the formation settles, partially reducing the formation volume as increased by fracturing fluid introduction. The formation healing stabilizes the sand introduced within the formation by the foam fracturing fluid. After the formation has healed the well is opened, the pressure drop in the formation causing the foam in the formation to break. The high pressure gas leaving the formation usually carries from the well substantially all of the liquids present in the fracturing area, leaving the formation and well clean and ready for commencement of production from the well. Because of the increased fracture area, and because the sand or other propping agent is uniformly distributed throughout the fracture area, and because of the fact that the sand does not settle from the foam fracturing fluid and is carried to the full extent of the fracture area, the production from the well is greatly increased.
FIG. 2 illustrates the well and formation after bleeding off of pressure to break the foam in the well, during the formation healing period.
FIG. 3 illustrates the well and formation following formation healing, with the gas and contained liquids being purged rom the formation and well.
The foam in formation 35 is indicated by reference numeral 38.
The amount of sand in the sand-water slurry may be varied to give the desired amount of sand in the foam fracturing fluid. The sand-water slurry at the mixer may contain from nearly zero pounds of sand or other proppant per gallon of water up to as many pounds of sand or proppant per gallon of water as may be pumped. The amount of sand in the foam fracturing fluid downhole may contain from about one-fourth pound of sand or other proppant per gallon of foam up to as much as can be pumped into the formation without screen out occuring at the formation face, depending upon reservoir conditions.
In an exemplary well fracturing treatment according to the invention, in a well having a depth of 7400 feet, the sand-water slurry contained from three to four and one-half pounds of sand, 20-40 mesh, per gallon of water at the mixer. A total amount of 4494 gallons of water was used in foam production, using 535,000 standard cubic feet of nitrogen gas to yield about 643 barrels (27,000 gallons) of foam fracturing fluid, including the pad and flush, at formation pressure, containing a maximum of 0.70 pounds of sand per gallon of foam. A foam pad (96 barrels) was first introduced into the formation, using 80,000 standard cubic feet of nitrogen gas commingled with 16 barrels of treated water. This was followed by injection of the foam facturing fluid (21,100 gallons) into the formation at an injection rate of 20 barrels (42 gallons/barrel) per minute, the total injection time being about 32 minutes, at a surface pressure of 4000 psi. The well was flushed with 43 barrels of foam (no sand) using 35,000 standard cubic feet of nitrogen gas. Ten gallons of stable foam surfactant per 1000 gallons of water was used in foam generation. The calculated diameter of the fracture area based on experience gained in field operation (excluding the nitrogen pad), was about 5000 feet, with a fracture height of about 12 feet. After completion of foam injection, nitrogen was bled off from the well head to break the foam in the well, and then the well was shut in and the formation was allowed to heal for twelve hours, after which the well was opened to break the foam in the formation and to purge the gas from the formation and well. Following this, production from the well was commenced, no swabbing or other well cleaning operation having been necessary. The well, a gas well, had produced 70,000 standard cubic feet per day prior to the fracturing treatment. After the fracturing treatment, the well production was 1,800,000 standard cubic feet per day.
Comparable results are obtained in both gas wells and oil wells.
To summarize, the invention provides a formation fracturing fluid, comprising a pressured stable foam comprising a liquid carrier comprising one or more liquids selected from the group consisting of water and oil, and a solid proppant comprising one or more materials selected from the group consisting of sand, crushed rock, glass, glass beads, and nut hulls, and a surface active material comprising one or more materials selected from the group consisting of soaps and surfactants, and gas comprising one or more gases selected from the group consisting of nitrogen, carbon dioxide, air, natural gas, and combustion exhaust gases, and having a percentage ratio, volume of gas; volume of gas and liquids in the foam between about 50% and about 90% at a well formation pressure, and methods for performing fracturing treatments using the same.
It will be realized that the fracturing treatments will be varied according to well depth and pressure, nature of the formation and formation fluid, area and depth of fracture, and the like.
While preferred embodiments of the invention have been described and illustrated in the drawings, many modifications thereof may be made by a person skilled in the art without departing from the spirit of the invention, and it is intended to protect by Letters Patent all forms of the invention falling within the scope of the following claims. | Foam fracturing fluids and methods for fracturing well formations using foam as the carrier for the propping agent are disclosed. The foams are stiff stable foams formed of a relative large amount of gas and a relative small amount of liquid. The foams are stable at surface pressures and remain stable when delivered into the well formation at the bottom of the well. | 8 |
This application is a continuation of application Ser. No. 917,249, filed Oct. 8, 1986, now abandoned, which is a continuation of application Ser. No. 778,272, filed Sept. 12, 1985, now abandoned, which is a continuation of application Ser. No. 707,165, filed Feb. 28, 1985, now abandoned, which is a continuation of application Ser. No. 294,862, filed Sept. 1, 1981, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic translating unit capable of translating sentences of different languages and, more particularly, to an electronic translating unit which is capable of searching without delay a translated sentence containing a plurality of selected words.
2. Description of the Prior Art
Prior art portable electronic translating units generally translate between words of different languages. Therefore, in order to form a translated sentence, select keys to or to , for example, are assigned to particular sentences. A translated sentence, for example, "I want . . . " may be formed and displayed by combining these select keys, for example, keys and . This type of electronic translating unit has thus been extremely inconvenient for a traveller in a foreign country since he or she must be well acquainted with the combinations of the select keys for operation purposes. The electronic translating unit of this type has thus been practically unusable.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an electronic translating unit which may be operated with a simple procedure by a traveller in a foreign country, for example, and which is capable of searching for a desired sentence and its translated equivalent.
It is another object of the present invention to provide an electronic translating unit which sequentially accesses and displays, upon input of a word, sentences which are associated with the input word and which are stored in advance, so that a desired sentence and its translated equivalent may be searched for.
It is another object of the present invention to provide an electronic translating unit which displays, upon inputting a plurality of desired words, sentences including these input words so that a desired sentence and its translated equivalent may be searched for without delay.
The above and other objects of the present invention will become apparent from the following description of the preferred embodiment of the present invention when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view showing an example of the arrangement of a control panel of an electronic translating unit according to the present invention;
FIG. 2 is a flow chart showing the translating mode of the unit shown in FIG. 1;
FIG. 3 is a block diagram showing the circuitry of the unit shown in FIG. 1 and FIG. 3A is a block diagram of the comparator of the present invention; and
FIGS. 4A through 4C are diagrams showing how words and sentences are stored in the respective memory circuits of the unit shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described in more detail referring to the accompanying drawings.
An example of the arrangement of a control panel of an electronic translating unit according to the present invention is shown in FIG. 1. The control panel shown in FIG. 1 has a keyboard 21 with character keys for selection and input of letters, kana or the like by a key operation to be described later, and function keys for controlling translating operations of various kinds; and a display 22 which has liquid crystal display elements of dot type, for example, to display a sentence consisting of a number of characters. The functions of the function keys on the keyboard shown in FIG. 1 are as follow:
______________________________________ ##STR1## to make each key function as a key of the character such as kana indicated above the frame of the key. ##STR2## to make each key function as a key of the letter, numeral or the like indicated within the frame of the key. ##STR3## to separate words or numerals. For example, to separate "12" from "36" as in "12·36". ##STR4## to sequentially display words or sentences for the purpose of search. ##STR5## to designate translation into an English word or an English sentence. ##STR6## to designate translation into a Japanese word or a Japanese sentence. ##STR7## to designate translation into a French word or a French sentence. ##STR8## to designate translation into a German word or a German sentence.Name to designate input of a proper noun.Time ( ) to designate input of a time.Way ( ) to designate input of a way.Much ( ) to designate input of amount, price, etc.Yes ( ) to designate a positive response upon a single operation.No ( ) to designate a negative response upon a single operation.______________________________________
According to this arrangement, words which are frequently used in general conversation may be input by a single key operation in order to save the trouble of correctly spelling these words each time.
The mode of operation of the electronic translating unit of the present invention will now be described with reference to the flow chart shown in FIG. 2, with the operation of the control panel assuming that translation is to be made from Japanese into English.
When the power switch at the upper right corner of the keyboard 21 is turned on (S1), the electronic translating unit may be operated. When the key below the power switch is depressed (S2), the respective keys will function as kana keys (indicated above each key) thereafter. When the kana keys are depressed for " " (station) (S3) for translation of this word into an English word as a Japanese to English dictionary, the display displays " " in Japanese (S4). The key is then depressed so that each key may now function as a key of the character within the frame. Upon depression of the key (S6), an English word "station" corresponding to " " is displayed (S7) at the display 22. The electronic translating unit thus functions as a Japanese to English dictionary.
In order to search for an English sentence including a particular word with the electronic translating unit shown in FIG. 1, the key is depressed while " " is displayed (S4). When keys and are depressed next (S5 and S8), examples of Japanese sentences associated with " " are first sequentially displayed (S9):
" " (Where is the station?)
" " (Where can I purchase the ticket?)
" " (Which platform does the train for . . . leave?)
" " (What time does the train leave?)
" " (What time does the train arrive?)
When the operator depresses the key (S10) when the desired Japanese sentence is displayed, the English sentence corresponding to the displayed Japanese sentence is displayed at the display 22. When the key is depressed for translation of " ", "What time does the train leave?" is displayed (S11).
However, if the sentences associated with " ", for example, are too numerous, the search for the desired English sentence may become very cumbersome. In order to prevent this problem, with the electronic translating unit of the present invention, a plurality of desired words are simultaneously input to allow search of sentences associated with all of these input words. In the example described above, the key is depressed (S5) while " " is displayed (S4). Additionally, the word " " (when) or " " (time) associated with time is input as a key word (S12). In this embodiment, up to three key words may be input and the key is depressed every time a key word is input. For example, after operating keys for inputting " ", the key , keys for inputting " ", the key , keys for inputting " ", and the key , the key is depressed to return the function of each key to that within the frame of the key and key is depressed (S15). Then, the Japanese sentence " " is immediately displayed (S16). In the manner as described earlier, when the key is then depressed (S17), the English sentence "What time does the train leave?" corresponding to the Japanese sentence is displayed at the display 22.
An example of the circuit configuration of the electronic translation unit operated by the key operations as described above is shown in FIG. 3. In FIG. 3, reference numeral 1 denotes a multi-digit liquid crystal display of dot type and 2 denotes a driver circuit for the liquid crystal display. Reference numeral 3 denotes a semiconductor circuit which serves as access controlling means comprising a random access memory (RAM) 4, a central processing unit (CPU) 5, and a read-only memory (ROM) 6. The RAM 4 is a temporary memory circuit which stores necessary data such as data input by the key operations, data from a read-only memory semiconductor circuit 8 to be described hereinafter, and data to be displayed at the display 22. The CPU controls data transfer, data processing, data comparison and so on of the overall electronic translating unit. The ROM 6 stores in advance the control data for commanding the control operation of the CPU 5.
Reference numeral 7 denotes a keyboard matrix circuit which serves as a data input device and as a sentence selection and translation instruction means (see below), comprising keys as shown in FIG. 1. Reference numeral 8 denotes the read-only memory semiconductor circuit which stores, in advance, words of a foreign language; for example, English words, Japanese words, and examples of sentences of both languages. Connecting wires 9 to 14 connect the respective elements of the circuit. Reference numeral 15 denotes a semiconductor circuit which is to be described hereinafter and is shown in FIGS. 4A and 4B; it is a word memory circuit which stores with indices Japanese words and words of a foreign language, for example, English words. Reference numeral 16 denotes a semiconductor circuit which is shown in FIG. 4C and which stores examples of English and Japanese sentences in correspondence with each other; it is a sentence memory circuit. Reference numeral 17 denotes a power switch and 18 denotes a small, built-in type battery.
The electronic translation unit, with the respective parts as described above and shown in FIG. 3, operates in the manner to be described below.
When the power switch 17 is turned on, the electronic translation unit may be operated. When the keyboard matrix circuit 7 operates as described above upon operation of the keyboard on the control panel, the input data selected by the key operations is stored in the temporary memory circuit 4. Code signals are assigned to the letter keys, kana keys, and function keys arranged on the keyboard. For example, binary code signals are assigned as
______________________________________ A 00001 B 00010 C 00011 . . . . . .______________________________________
and so on up to "Z"; and further binary code signals are assigned as
______________________________________ 100001 100010 100011 . . . . . .______________________________________
and so on up to " "
Therefore, when " " is input by the key operations, binary code signals
100100 for " " and
100111 for " "
are stored in the temporary memory circuit (RAM) 4.
On the other hand, the binary code signals "100100" and "100111" corresponding to the kana " " and " " are similarly stored in the read-only memory semiconductor circuit 8. From the time a function key such as or is depressed, the central processing unit (CPU) 5 starts comparing the contents in the temporary memory circuit 4 with the contents as shown in FIG. 4B in the word memory circuit 15. Various measures may be taken to shorten the period of time required for such a comparison. However, describing the basic configuration of the comparing means, as shown in FIG. 4B, a series of words starting with " " are supplied to the central processing unit 5. The data from the temporary memory circuit (RAM) 4 and the data from the word memory circuit 15 are supplied to an AND gate, the output of which is written in a register, as shown in FIG. 3A. The comparator thus sequentially detects the coincidence of both data. When the coincidence is detected for the binary code signals "100100" and "100111" corresponding to " " with every digit coinciding, an address X7 stored in item β in FIG. 4B corresponding to the Japanese word " " which in turn corresponds to this combination of binary code signals is read out from the word memory circuit 15 to indicate the address of the corresponding foreign word. This address is written in the temporary memory (RAM) 4. Simultaneously with this, an address 101 read out from item γ in FIG. 4B which stores the sentence associated with this word is written in the temporary memory circuit (RAM) 4.
If the function key which has been depressed is the key , the series of binary code signals corresponding to the English word "station" at the address X7 which is written in the temporary memory circuit (RAM) 4 in this manner is written in the temporary memory circuit (RAM) 4 through the central processing unit (CPU) 5 and is then supplied to the display 1. The series of binary code signals representing the English word is decoded into a series of character signals which is supplied to the display 1 for display of the English word "station". Thus, the translation operation in response to the depression of the key is completed.
On the other hand, if the key as the function key is depressed after " " is input by the operation of the keyboard, the address X7 of the foreign word and the address 101 of the sentence associated with this word are read out from the read-only memory semiconductor circuit 8 and the unit holds this condition until the next kana key or key for searching sentences is depressed. Each time the key is subsequently depressed, according to the address 101 of the associated sentences which is stored in the temporary memory circuit (RAM) 4, sentences corresponding to "101" which in turn corresponds to " " in item β in FIG. 4C are sequentially written, through the central processing unit (CPU) 5, in the temporary memory circuit (RAM) 4 in the order stored at this address from the sentence memory circuit 16 storing the sentences in the form shown in FIG. 4C. Then, in the same manner described above, the series of binary code signals are sequentially decoded into sentences and displayed at the display 1. When the key is depressed as the desired sentence is displayed during this search procedure, the English sentence corresponding to the selected sentence is decoded and displayed in a similar manner.
When the key is depressed after the input of the word " " and then another word is input by depression of kana keys, the data associated with " " described above, that is, the address X7 of the corresponding English word and the addresses 101 of the sentences associated therewith are all written from the word memory circuit 15 to the temporary memory circuit 4 as shown in FIG. 4B. " " is displayed at the display 1, and the kana keys are depressed to input another word " " (time), for example. Then, when the function keys such as the key and the key are depressed, the data thus input is compared with the data as shown in FIG. 4B which is in the word memory circuit 15. As a result of this comparison, the address X6 of the English word corresponding to " " (time) is read out and written in the temporary memory circuit 4. The input data is also compared with the data as shown in FIG. 4C which is stored in the sentence memory circuit 16, and the address 1 of item α for storing the sentences associated with " " (time) are read out and are also written in the temporary memory circuit (RAM) 4. When the search key is subsequently depressed, the series of binary code signals corresponding to sentences with which the item α corresponding to " " (time) is "1" and the item β corresponding to " " (station) is "101" are sequentially read out from the sentence memory circuit 16 and are written in the temporary memory circuit 4. These code signals are then sequentially decoded into sentences and displayed at the display 1 for search. When the key is depressed when the desired sentence (for example, " ") is displayed during this search period, the corresponding English sentence ("What time does the train arrive at?") is displayed, thus completing the translation of a sentence based on a plurality of words as key words for search. | An electronic translating unit has switches for inputting a first language or a second language; a memory consisting of a first memory section for storing words of said first language and addresses of sentences associated with said words, a second memory section for storing words of said second language and addresses of sentences associated with said words, and a third memory section for storing said sentences of said first language and said sentences of said second language corresponding thereto; and access controlling device for accessing, upon input of words of one of said languages, words of the other, said language corresponding thereto, and said addresses of said sentences in either of said languages from said memory, sentence selecting device for accessing and selecting said sentences from said third memory section according to said addresses, and display for displaying said sentences. | 6 |
The present invention relates to manufacture of plastic shrink wrap coverings on glass containers of the type disclosed in U.S. Pat. No. 3,760,968.
BACKGROUND OF THE INVENTION
In the manufacture of plastic coated containers of the type disclosed in said patent, glass bottles or like containers are preheated or conditioned to temperature above ambient temperature and conveyed in a vertical upright position by a ware handling conveyor which has spaced chucks thereon. The chucks grip the bottles by the neck finish and the conveyor carries them in single file past a sleeve making apparatus. The sleeve making apparatus receives a continuous web of the oriented heat shrinkable plastic, preferably a foam having some stiffness, that has been preprinted with a desired decoration. The machine cuts successive lengths of the material from the web and feeds them to individual mandrels on a rotary turret. Each cut length of the material is wrapped around the periphery of the mandrels so that the leading and trailing ends overlap and the ends are united to form a cylindrical sleeve with its axis disposed vertically. The mandrels move in registered position with containers on the conveyor in an assembly station wherein the conveyor path is in overlying relationship with the path of the underlying mandrels. The sleeves are stripped axially from the mandrels and telescopically placed about the bottle such that a lower end portion overhangs the bottom end of the bottle. In this fashion, the bottle and sleeve are conveyed by the ware conveyor to an oven or like heating device and heated sufficiently to shrink the plastic sleeve snugly and firmly about the exterior of the bottle.
Various devices have been employed to assure the position of the sleeve on the bottle from the time the sleeve is initially assembled until it shrinks. Zonal heat bands have been used with some success, such as is disclosed in the copending application of R. A. Ashcroft, Ser. No. 464,224, filed Apr. 25, 1974 (now U.S. Pat. No. 3,959,065), which is of common ownership with the present application.
SUMMARY OF THE INVENTION
In making plastic wrapped glass containers covered with a polyethylene, or certain other polyolefins, polymers or copolymers as mentioned hereinafter, some difficulty is experienced in zonal heating because of the time and distance available to maintain the assembly of the sleeve on the bottle. Polyethylene materials of the heat shrinkable variety have a tendency under application of heat to first become very limp and actually grow or expand as a sleeve on the bottle just before shrinkage occurs. This tendency causes some or several of the sleeves to slip from position on the bottle in the heating oven, or on the way thereto, such that "off-ware" or rejects result to an intolerable degree.
By the present invention, the sleeves are supported in their path to and into a part of the oven, at least until shrinkage has occurred and proper position of the sleeve shrunken on the bottle is assured. This is accomplished by a support bar set at the correct height, or spacing from the bottoms of the bottles on the conveyor, such that in position as assembled on the bottle, as aforesaid, the lower edge of the sleeves engage and glide over the support bar top surface. This surface is preferably coated with a material to reduce friction and is somewhat rounded to aid in friction reduction. One such low friction coating is "Teflon" and may be applied in several convenient forms, i.e., powder, tape or sprayed-on coating.
Inasmuch as the support for the sleeve must be maintained through a portion of travel of the conveyor for the bottles in the hot atmosphere of the heating device, e.g., an elongated tunnel-type oven open at its opposite ends through which the path of the conveyor travels, the support surface and the support bar will assume the operating temperature of the oven after a time. The ovens are operated at or above 400° F for shrinking polyethylene sleeves onto bottles. This hot surface would render the plastic soft and pliable by contact and result in sticking, whereby the sleeves would become deformed at the lower edge and also result in producing intolerable quantities of off-ware.
It is therefore a very essential feature of the invention to cool the sleeve support surface below such temperature at which sticking takes place. In operating with polyethylene materials, the support bar should be cooled to maintain its temperature below 200° F and preferably below 150° F. As such, the sticking problem is overcome, i.e., by employing low friction coatings on the bar surface and cooling it to these temperatures.
Although various coolant media may be employed, a water cooled support bar is preferred. A pump-sump supply is connected to the bar, which is constructed as a pipe within a pipe and the coolant is circulated continuously internally of the support bar. Refrigeration by cooling coils implanted in the sump may be used as necessary to maintain a supply of the low temperature coolant in a closed system.
Other advantages and features of the invention will be more readily apparent to those skilled in the art from the following detailed description of the drawings, which illustrate apparatus for carrying out the method of the invention, on which:
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional, side elevational view of a tunnel-type oven for shrinking sleeves onto bottles, and includes the sleeve support bar and coolant system of the invention;
FIG. 2 is a spacial perspective view, partly broken away and sectioned, showing the assembled position of a polyethylene sleeve on a glass bottle during travel with the bottle conveyor into and through part of the oven;
FIG. 3 is a spacial perspective view, partly broken away and sectioned, which is like FIG. 2, illustrating the sleeve shrunken onto the bottle;
FIG. 4 is a three-quarter front perspective view of the machine for applying polyethylene sleeves onto glass bottles and the heating device for preheating the bottles before receiving the sleeves and the heating device for shrinking sleeves onto the bottles after the two are assembled, including the bottle conveyor, which incorporates the features of the invention for performing the method.
DESCRIPTION
Shown on FIG. 4 is a machine for producing plastic sleeves on a turret machine 10, assembling them telescopically over glass bottles carried by the conveyor 11 and shrinking them thereon in a heating apparatus 12. The glass bottles B in the examples of the present disclosure, after having a shrunken plastic covering thereon, form a composite container of a type described and shown in the aforementioned U.S. Pat. No. 3,760,968, as shown on FIG. 3.
Again referring to FIG. 4, in production of these containers, glass bottles B are picked up by the neck chucks 13 spaced along the endless bottle conveyor 11 and carried through a heating section 12b of the oven structure 12. After receiving sleeves of the plastic material, as described hereinafter, the conveyor path extends to the tunnel chamber 12a of the heating device 12, enters chamber 12a and extends through the length thereof. The heat chamber 12a of the oven is operated as a circulating hot air chamber or infra-red heaters provide the oven temperature for shrinking the plastic cylinder-like sleeves S onto bottles B.
The plastic material is a polyolefin or copolymers of olefins, for example polyethylene, or laminates of polyolefins, e.g., polyethylene foam layer and polyethylene film or polystyrene foam layer and ethyl acrylate film. The plastic material in sheet form is highly oriented in the longitudinal dimension of the web (circumference of sleeve S) in relation to any orientation of the plastic sheet in its transverse dimension (height of sleeve S). Examples of plastic sheet material that may be run in form of web 34 are foamed polyethylene on the order of 0.008-0.02 inch thickness highly oriented in the running direction of web 34.
In a more general way, the plastic sheet material may be a form of a contractible polyolefin or copolymer of olefins with vinyl esters, for example, vinyl acetate, or with alpha, beta, monoethylenically unsaturated acids, such as ethyl acrylate or ethylene ethyl acrylate. The plastic is preferably in form of a foam sheet or a foam/film laminate sheet. The general property of such materials in contraction (shrinking) is a first pliable, plastic state (very limp condition) at which time the sheet material tends to sag or slump, followed by an almost instantaneous shrinkage reaction. This invention deals with the propensity in the material to slump and grow during the initial stages of heating in the application of the sleeves of the material onto a rigid base article in the production herein described.
The inner circumference of sleeve S (FIG. 2) is slightly more than the exterior circumference of the bottle B so that the sleeve S may be telescopically applied over bottle B to a desired elevation on the latter. The preferred thermoplastic may be of foamed structure and such a material on the order of ten thousandths of an inch or greater in thickness provides a suitable sleeve S for handling on the machine.
LIQUID-COOLED SLEEVE SUPPORT BAR
Within a short span of travel of the conveyor 11 for bottles beyond the sleeve assembly point, the lower edge S' of the sleeve passes directly over a sleeve support bar 40 which extends in an underlying relationship to bottles B along the path into and through some of the length of the oven. Support bar 40 is supported by its connection on a cantilevered bracket 61 fastened to a vertical structural beam 62 at the front end of the oven 12 and may be adjusted for height on the vertical beam support. The top surface of support bar 40 should be positioned approximately one half inch below the bottom of the bottles B, which is approximately equal to the amount sleeves S overhang the bottom end of the bottles in the assembly position. This overhang dimension assures the sleeve will shrink around the lower corner radius of the bottle and onto the bottom end of the bottle.
Referring to FIGS. 1 and 4, support bar 40 is shown in its relationship with cure oven 12. Bottle conveyor 11, represented by dashed line, extends in a straight line through the length of oven 12. As bottles B enter the oven at its front entrance of chamber 12a, the lower edges S' of the plastic sleeves are supported in position by the telescopic fit on the bottles and assured this position by riding on the top of support bar 40. The cure oven 12 is heated by linearly spaced infra-red burners or hot air to a temperature in the range of 400°-1000° F. The support bar 40 is liquid cooled, as will be presently described, to a temperature below 200° F so as to avoid sticking of the plastic sleeves on the bar surface. The top bearing surface of bar 40 is coated with a lubricious surface layer, an example of which is "Teflon" in the form of a Teflon tape 41 or a thin Teflon surface coating.
The support bar 40 consists of one metal pipe 42 inside another pipe 43. The pipe 42 is closed at its one end 44 and a water outlet pipe 45 is connected thereat. The opposite end 46 of pipe 42 is open and is spaced from the closed end 47 of outer pipe 43. The aft end of pipe 43 may be slightly sloped downwardly at 48. The forward end 49 of pipe 43 is curved downwardly from the horizontal sleeve support plane (shown in dotted line extension) for providing a gentle camming action in the engagement of the support bar with the sleeves S. The outer pipe 43 is curved at forward end 49 in the horizontal plane to fit into position at turret 10a and avoid interference with mandrels 29 thereon (FIG. 4). Adjacent the curved forward end portion 49 of pipe 43 is a water inlet pipe 50 connected thereto. The preferred liquid coolant is water, although other liquid coolants may be substituted in the system. Liquid coolant is supplied from tank 51 into pipe 50 by pump 52 having a snorkel feed pipe 53 in the liquid. The pump may be an electric motor driven pump assembly of conventional type. The outlet of pump 52 is connected to the inlet pipe 50 for the outside pipe 42 of the apparatus. Liquid is pumped into pipe 43, along the length thereof, cooling the outside pipe and coating to an operating temperature. Spent coolant enters the far open end 46 of inner pipe 42 for returning used coolant to the tank. Circulated coolant is drained through outlet pipe 45 and back to the tank 51 for recirculation by pump 52.
The length of the support bar 40 should be long enough to extend from its outer sloped end 49 near the turret machine 10 to and into oven 12 a sufficient extent to allow for oven heat to shrink the sleeve S substantially or enough to grip the bottle firmly. Usually, this requires the sleeve S to traverse approximately one half of the length of the oven, shown on FIG. 1. The oven length extends from the entrance opening 12a to the exit opening at 12e. At the time bottle B and sleeve S thereon are conveyed away from the turret path of the turret machine 10 (FIG. 4), the bottle and sleeve assembly are conveyed directly over the top of support bar 40. In the initial stages of travel toward and into the oven 12, (before shrinking of the plastic sleeve takes place) the bottom edge S' of the sleeve S rides over the reduced friction top surface 41 of the support bar. At a later stage of travel inside oven 12, the plastic will shrink; whereupon, the edge S' of the sleeve will raise onto the bottle bottom such as is shown by the bottle at the right hand side of FIG. 1.
In the present invention, the sleeve support bar apparatus remains cool so that the thermoplastic sleeves do not stick on the bar as they move thereover, plus the support bar is designed with the coolant inlet pipe encircling the coolant outlet pipe, so as to be very compact and versatile in operation. The preferred circulation is that shown; however, the inlet and outlet pipes may be switched at the pump and tank reversing the circulation. This cooling arrangement will operate best by having the fresh cooling liquid supplied to the outside pipe (as shown) which provides faster cooling of the surface 41.
The support bar extends into the middle of the oven and therefore would become extremely hot if not cooled. Because some species of polyolefin materials shrink more slowly in relation to production speeds of the assembly machinery, it is necessary to support the sleeves into the oven at least until substantial shrinkage of the material takes place so as to hold the sleeves firmly in place on the container. To facilitate service and operation of the support bar, the disclosed cantilevered support thereof from the single bracket located outside the oven chamber is important.
THE MACHINE
The bottles B are fed to and loaded on the neck gripping overhead chucks 13 connected to an endless driven carriage comprised of upper and lower chains 14 and 15, respectively, extending around end-turn gears 16 and 17 each keyed onto the vertical shaft 18. A bull gear 19 is also connected at the upper end of shaft 18 in mesh with drive gear 20 connected to the power drive means (not shown) by the drive shaft 21. Power is transmitted to gear 19 to rotate it and shaft 18 counter-clockwise on FIG. 4 and drive the chains 14, 15 in a counter-clockwise direction through the endless path of the conveyor. Chucks 13 are mounted on carriage brackets 22 connected to links of the chains 14, 15. The several carriage brackets have spaced rollers 23 on their back sides running in stationary tracks 24 and 25 around the path of the conveyor. The chucks 13 are each vertically, slidably mounted on their respective carriage brackets 22 and the vertical elevation of chucks 13 is controlled by the cam roller 26 rotatably connected on the upper element 13a of the chuck running in cam track 27 fastened rigidly on the machine. The chucks 13 have three lower jaws 13b which open and close about the top end of bottle B. The jaws 13b are attached to a circular arbor including a wheel element 13c that is rotatable about shaft 13d of the chuck so that friction engagement of the periphery of the wheel element 13c of the arbor with a stationary element (to be described hereinafter) anywhere along the path of the conveyor imparts rotation of the chucks and bottles thereon about the axis of the shaft 13d.
The end-turn portion of the conveyor mechanism is supported by the upper frame 28 rigidly supported on the front wall of the oven 12.
Beneath the conveyor end-turn portion, just described, is the rotary sleeve turret 10 which is coaxial with the vertical shaft 18. Turret machine 10 is comprised of an upper annular turret 10a rotated counter-clockwise about shaft 10b over the lower stationary frame 10c.
The turret machine 10 includes a plurality of spaced mandrels 29 mounted on turret 10a whose peripheral spacing on turret 10a coincides radially and with the peripheral spacing of chucks 13 in the end-turn portion of the conveyor path. The chucks 13 have their centers in registry with the vertical central axes of underlying mandrels 29. At the base of each mandrel in an inactive position there is an annular, encircling push-up bar or stripper element 30 connected onto a vertical operating rod 31 by an arm. Rods 31 are each vertically slidable on the guides 32 connected with turret 10a and under control of the circular cam 33 extending around frame 10c in which a cam roller 33a connected to rod 31 is in running engagement. The cam 33 is a stationary element of turret frame 10c. The pattern of the rise and fall of cam 33 provides the proper vertical reciprocating motion to rod 31 and push-up bar 30 responsive to rotary movement of turret 10a.
Connected for operation with turret machine 10 is mechanism for feeding a supply of plastic strip stock and forming it to sleeve lengths. The strip stock is shown as a running web 34 guided through opposed feed rollers 35, 36 and onto the sleeve drum 37. The web 34 on drum 37 has forward lengths cut therefrom by rotary knife 38, and the cut lengths 34a are held onto drum 37 by vacuum until the leading edge thereof engages a mandrel 29 of turret 10a. The mandrel at this point is engaged by its drive means of the turret machine to rotate it more than 360° winding the strip 34a about a mandrel 29 in an end-to-end overlap of the strip to form a cylindrical shape. Thereafter, means on the turret machine connect the overlapped ends at a vertical seam to complete formation of a cylindrical, hollow sleeve S of the plastic material.
After the plastic strip 34a is wound on mandrel 29 and seamed to form sleeve S, the mandrel 29 and chuck 13 travel together through an assembly station during which the two are at zero angular velocity and displacement with respect to each other. In this span of travel, roller 33a begins its rise on cam 33, and push-up bar 30 rises on mandrel 29, which elevates sleeve S into the telescopic assembly position on bottle B (FIG. 1). Sleeve S is supported thusly by push-up bar 30 during the flat span A of cam 33.
At the point where the cam 33 falls away and push-up bar 30 is retracted, the bottle carriage path diverges tangentially away from the arc path of turret 10a. At this point, the conveyor path coincides with the length of support bar 40 to, into and over part of the length of the oven chamber 12a. The apparatus functions to perform the method described herein, which results in the production of the composite container such as is shown on FIG. 3.
Further modifications may be resorted to without departing from the spirit and scope of the appended claims. | There is disclosed a method of covering glass containers with a preformed, cylindrical sleeve of a polyethylene or like polyolefin material, or laminates of polyolefins, that are heat shrinkable circumferentially of the sleeve and made from sheet of a foam or a laminate of said plastic material such as a foam-film laminate. Upon application of heat, the sleeve initially softens or becomes limp, and grows or enlarges, such that in its telescopic assembly on the upright bottle it tends to slip from position. The method includes supporting the sleeve from underneath during heating it for shrinkage by conveying the container and sleeve over a water-cooled sleeve support bar extending into the heating device a substantial distance allowing the sleeve to shrink onto the bottle. The sleeve support bar includes a lubricious surface layer adjacent the sleeve. The lubricious layer combined with water cooling maintains support surface below 200° F, preferably below 150° F, and prevents sticking of the plastic on the support. | 1 |
BACKGROUND OF THE INVENTION
The invention proceeds from a device and a method for metering a liquid into the exhaust tract of an internal combustion engine according to the preamble of the independent claims.
For the aftertreatment of exhaust gases from an internal combustion engine, DE 44 36 397 B4 discloses the delivery by a delivery element of a liquid, for example liquid urea solution or fuel, from a reservoir to an injection valve, which meters a required quantity of the liquid into the exhaust tract. Here the injection valve is arranged on the exhaust tract in such a way that its injection orifice is directed into the exhaust tract.
In operation very high temperatures can occur on the injection valve, particularly at its injection orifice, due to hot exhaust gases in the exhaust tract. This negative effect may be further exacerbated by the need to arrange the injection valve in proximity to hot components, such as the internal combustion engine, for example, or an exhaust gas turbocharger. There is the risk here of an unwanted thermal decomposition of the liquid in the injection valve or a formation of deposits in the injection orifice of the injection valve. The metering accuracy of the injection valve may thereby be impaired, which in extreme cases can lead to failure of the injection valve.
In order to avoid these very high temperatures in the injection valve, DE 10 2007 011 686 A1 discloses an injection valve with cooling in the area of the injection orifice. In addition, DE 10 2006 019 973 A1 discloses a metering system for providing reducing agents in the exhaust tract, in which a metering valve of the metering system can be cooled by a cooling circuit.
SUMMARY OF THE INVENTION
The device according to the invention and the method according to the invention for metering a liquid into the exhaust tract of an internal combustion engine by contrast has the advantage that the injection valve opens when the restrictor element releases the volumetric flow of the liquid to the injection valve. This means that it is possible to adjust to any flow, however small, through the cooling circuit of the device, so that the cooling of the injection valve can be controlled as a function of the demand and does not always ensue at the maximum delivery of the pump. Less power is therefore needed in order to deliver the liquid through the injection valve, which leads to an increased efficiency of the internal combustion engine. In addition, a restrictor in the inlet to the injection valve gives the injection valve greater robustness to withstand pressure fluctuations in the liquid circuit upstream of the restrictor element, since such pressure fluctuations are damped by the restrictor element. Reducing such pressure fluctuations avoids injection control defects and leads to a higher metering accuracy of the injection valve.
In an advantageous development the injection valve comprises a further restrictor, arranged in the closing member, for example, which has a greater restricting effect than the restrictor element when the flow through the first restrictor element is fully opened. The further restrictor serves to limit the maximum cooling quantity through the cooling circuit of the injection valve, in particular the return quantity from the cooling circuit, so that, for example, a pressure can be built up in the injection valve.
In a further advantageous development a first operating state, in which the restrictor element determines the volumetric flow through the cooling circuit of the injection valve, is succeeded by a second operating state, in which a pressure of the liquid in the injection valve is increased when the volumetric flow to the injection valve is released and is restricted by the further restrictor in the injection valve, and the injection valve opens when a defined pressure level is reached. This development allows the injection valve to be designed as a pressure-controlled valve, which opens in excess of a defined pressure threshold. Here the pressure in the injection valve may be adjusted solely via the restrictor element, if the further restrictor has a fixed cross section and therefore from a certain release of the restrictor element onwards becomes the flow-determining restrictor of the cooling circuit.
In an advantageous embodiment of the device the closing member of the injection valve is embodied as a valve needle, in particular as a hollow needle. Designing the closing member as a valve needle allows a liquid return of the injection valve to be effected along the valve needle in the closing member, which return, in the case of a hollow needle, may be formed inside the hollow needle, so that the injection valve can be of very compact design.
In a further advantageous embodiment of the device the restrictor element comprises a metering element, for example a metering pump, in particular an electrically controlled metering pump, a variable restrictor and/or a metering valve. A metering pump is advantageous since it is capable of boosting the pressure acting on the liquid, so that the liquid can be injected at a higher injection pressure and can be atomized more finely.
In a particularly advantageous embodiment of the device the metering pump does not fully prevent the supply of liquid to the injection valve when the metering pump is in a deactivated operating state. This advantageously ensures that even with the metering pump deactivated liquid can be delivered through the injection valve for cooling purposes. Furthermore in the activated operating state the metering pump is capable of generating a pressure which exceeds the inlet pressure to the restrictor element and therefore leads to an excess pressure. The injection valve can therefore also be adjusted to opening pressures which exceed the inlet pressure to the restrictor element. The liquid supply to the restrictor element can thereby be of a particularly simple and cost-effective design, and this allows a connection to liquid circuits already existing, for example the low-pressure circuit of a fuel injection system.
In a further advantageous development the injection valve comprises a cooling circuit with a liquid inlet and a liquid return, the liquid return being arranged in an inner area of the injection valve, in particular inside the closing member. Arranging the liquid return in an inner area of the injection valve means that the heated liquid can be discharged from the cooling circuit of the injection valve over a relatively short distance, so that further heating of the liquid and possible thermal decomposition or ageing are minimized.
In a further advantageous development a filter element, for example a disk filter, is arranged in a housing of the injection valve, particularly in a liquid feed line to the cooling circuit. Incorporating a filter element in the injection valve serves to increase the robustness of the injection valve towards particles. With particles there is a risk of these particles being deposited in areas relevant to the functioning of the injection valve, in particular on the valve seat and in the further restrictor, and impairing the working of the valve or causing increased wear, and in extreme case particles may lead to a complete failure of the injection valve. The filter element reduces this risk, which leads to a longer service life and increased working accuracy over the operating life of the injection valve.
In a further advantageous embodiment of the device the cooling circuit of the injection valve cools an area of the injection valve facing the exhaust tract, in particular a valve seat. The cooling of the valve seat by the cooling circuit affords the advantage that it specifically cools precisely that point of the injection valve subjected to the greatest thermal load, in particular the area of the valve seat and the injection orifice, and therefore minimizes the risk of deposits on the valve seat and coking of the injection orifices.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary embodiments of the invention are represented in the drawings and are explained in more detail in the following description.
FIG. 1 shows a schematic representation of the device according to the invention for metering a liquid into the exhaust tract of an internal combustion engine.
FIG. 2 shows a sectional representation of a first exemplary embodiment of the device according to the invention.
FIG. 3 shows a sectional representation of a further exemplary embodiment of the device according to the invention.
FIG. 4 shows a sectional representation of a further exemplary embodiment of the device according to the invention.
DETAILED DESCRIPTION
FIG. 1 represents the device 100 according to the invention for metering a liquid 12 into an exhaust tract 20 of an internal combustion engine 10 . The device 100 here comprises the components represented inside the dashed line.
A reservoir 13 for storing the liquid 12 is connected to a suction-side inlet 21 of a pump 14 via a first connecting line 16 . Via its delivery-side outlet 22 the pump 14 is connected by a further connecting line 17 to a restrictor element 34 . From the restrictor element a further connecting line 18 leads to an injection valve 50 , which is arranged on the exhaust tract 20 of the internal combustion engine 10 . The injection valve 50 comprises a housing 51 , which is of trough-shaped design, and can be closed by a closing member 61 on its side facing the exhaust tract 20 . On its side remote from the exhaust tract 20 the housing 51 is closed by a cover 59 , which guides the closing member 61 . A cooling circuit 75 , which in an outer area of the injection valve 50 leads from the connecting line 18 to a valve seat 53 , which with the outwardly opening closing member 61 is closed by a valve disk 54 , is formed in the injection valve 50 . From the valve seat 53 the cooling circuit 75 in an inner area of the injection valve 50 leads along the closing member to the cover 59 . The cover 59 is connected via a return line 19 to the reservoir 13 .
The pump 14 draws a volumetric flow 15 of the liquid 12 from the reservoir 13 via the connecting line 16 and delivers it via the connecting line 17 to the restrictor element 34 . In the initial state the restrictor element 34 has a restricting effect, so that the volumetric flow 15 flows from the restrictor element 34 at reduced pressure via the connecting line 18 to the injection valve 50 , the connecting line 18 being connected to the cooling circuit 75 of the injection valve 50 . The main direction of flow of the liquid 12 represented by arrows in the drawing.
As it flows through the cooling circuit 75 , the volumetric flow 15 of the liquid 12 cools the area of the valve seat 53 of the injection valve 50 particularly subjected to thermal load and flows back to the reservoir 13 via the return line 19 , which is connected to the cover 59 of the injection valve 50 . If the restrictor element 34 is activated in such a way that the volumetric flow 15 to the injection valve 50 is released by the restrictor element 34 , a pressure of the liquid 12 acting on the closing member 61 increases in the injection valve 50 . If the pressure in the injection valve 50 reaches or exceeds a threshold, which is needed in order to overcome a closing force acting on the closing member 61 , the closing member 61 opens and allows a metering of the liquid 12 into the exhaust tract 20 of the internal combustion engine 10 . An aqueous urea solution or a fuel, in particular diesel fuel, is suitable as liquid 12 for use in this device 100 .
Alternatively the liquid 12 may also be stored in and fed to the device 100 from a pressurized circuit, for example a low-pressure circuit of a fuel injection system. In this case it is possible to dispense with the pump 14 , if the pressurized circuit provides the liquid 12 with a pressure which exceeds the threshold, which is needed in order to overcome the closing force acting on the closing member 61 in the injection valve 50 .
As a further alternative the injection valve 50 may also be embodied as an inwardly opening valve, in which the valve seat 53 may alternatively also be closed by a valve ball 55 . In the device claimed the cooling of the injection valve 50 by the cooling circuit 75 is not limited to the area of the valve seat 53 but may also dissipate the heat from elsewhere, in particular from the housing 51 of the injection valve 50 , so that a direct incident flow against the valve seat 53 is not absolutely essential. Here the cooling circuit 75 may also be arranged in the portion in the outer area of the injection valve 50 leading from the valve seat 53 to the return line 19 , in particular in the housing 51 . In this case the return line 19 may alternatively also be connected directly to the housing 51 .
FIG. 2 shows a sectional representation of a further exemplary embodiment of the device 100 according to the invention. Here the reservoir 13 for storing the liquid 12 is connected via the first connecting line 16 to the suction-side inlet 21 of a pre-supply pump 23 of a fuel injection system 30 . The pre-supply pump 23 is connected, via the further connecting line 17 to a metering valve 32 acting as restrictor element 34 , and via a further connecting line 25 in a known manner to the fuel injection system 30 supplying the internal combustion engine 10 . The metering valve 32 is connected via the connecting line 18 to the injection valve 50 , which is arranged on the exhaust tract 20 of the internal combustion engine 10 . The injection valve 50 comprises a housing 51 , which is of trough-shaped design, and on its side facing the exhaust tract 20 can be closed by a closing member 61 situated on a central axis 60 of the injection valve 50 . Here a valve seat 53 , which can be closed by a valve disk 54 formed on the closing member 61 , is formed on an end face of the housing 51 facing the exhaust tract 20 . The closing member 61 is embodied as a hollow needle 63 , which is guided by an insert 52 , which is pressed in the cover 59 . A valve spring 64 is arranged between a bearing surface 68 , formed on the end face of the housing 51 facing the exhaust tract 20 , and a further bearing surface 69 , embodied as a spring plate 65 of the closing member 61 . The connecting line 18 opens via an angled port 81 and a connecting port 82 in the cover 59 into an annular orifice 57 , which is defined by the cover 59 and the housing 51 . Here a sealing element 72 in the form of an O-ring 73 , which seals off the injection valve 50 externally to prevent an unwanted escape of the liquid 12 , is arranged between the cover 59 and the housing 51 . The annular orifice 57 is hydraulically connected via a disk filter 58 , which is formed by the insert 52 and the housing 51 , to the cooling circuit 75 , which comprises a liquid inlet 76 and a liquid return 77 . In order to obtain an optimum cooling effect, the liquid inlet 76 arranged in an outer area of the injection valve 50 leads to the area of the valve seat 53 subjected to a high thermal load, whilst the liquid return 77 is arranged inside the closing member 61 embodied as a hollow needle 63 . The liquid inlet 76 and the liquid return 77 are connected to one another via a further restrictor 62 , which is embodied as a port 66 in the closing member 61 embodied as a hollow needle 63 . The liquid return 77 is connected via an orifice 83 in the insert 52 and an orifice 56 in the cover 59 to the return line 19 , which connects the injection valve 50 to the reservoir 13 .
The pre-supply pump 23 of the fuel injection system 30 connected to the reservoir 13 via the connecting line 16 delivers a volumetric flow 15 of the liquid 12 to the metering valve 32 via the connecting line 17 . In the initial state the metering valve 32 restricts the volumetric flow 15 to the injection valve 50 , in such a way that the volumetric flow 15 of the liquid 12 is delivered to the injection valve 50 at reduced pressure via the connecting line 18 , the liquid 12 flowing via the angled port 81 and the connecting port 82 out of the connecting line 18 into the annular orifice 57 of the injection valve 50 . The liquid 12 passes via the disk filter 58 into the cooling circuit 75 of the injection valve 50 . As it flows through the liquid inlet 76 , the heat of the injection valve 50 , subjected to a thermal load, is absorbed and is dissipated via the liquid return 77 . In passing from the liquid inlet 76 into the liquid return 77 the liquid 12 of the port 66 flows through in the closing member 61 , which is embodied as a hollow needle 63 and which acts as a further restrictor 62 . Here the restriction effect of the port 66 in the initial state does not determine the rate of flow, so that only a slight pressure increase, if any, occurs in the liquid inlet 76 and the pressure in the liquid inlet is below the threshold, so that the pressure is not sufficient to overcome the spring force of the valve spring 64 and to lift the valve disk 64 of the closing member 61 off from the valve seat 53 of the injection valve 50 . In the initial state, therefore, no liquid 12 is metered into the exhaust tract 20 of the internal combustion engine 10 . The liquid 12 flows via the liquid return 77 through the orifice 83 in the insert 52 and the orifice 56 in the cover 59 and via the adjoining return line 19 back to the reservoir 13 .
If the metering valve 32 , proceeding from the initial state described, is opened by electrical activation, the volumetric flow 15 of the liquid 12 to the injection valve 50 is released, the actuation of the metering valve 32 causing the volumetric flow 15 through the injection valve 50 to be limited by the port 66 , acting as further restrictor 62 , as it passes between the liquid inlet 76 and the liquid return 77 of the cooling circuit 75 . The pressure in the injection valve 50 thereby increases in the liquid inlet 76 or, at least briefly, exceeds the threshold 28 , which is sufficient to overcome the spring force of the valve spring 64 . Overcoming of the spring force of the valve spring 64 causes the valve disk 54 to lift from the valve seat 53 and allows metering of the liquid 12 into the exhaust tract 20 of the internal combustion engine 10 . Due to the metering or the restriction of the volumetric flow 15 by the metering valve 32 , the pressure in the liquid inlet 76 dips below the threshold 28 again, so that the closing member 61 is returned into the initial position again by the valve spring 64 and the injection valve 50 closes.
Alternatively the metering valve 32 may also be actuated mechanically, pneumatically or hydraulically. The cover 59 of the injection valve 50 may alternatively also be integrally formed with the insert 52 , the closing member 61 also being alternatively guided in the housing 51 and/or in the cover 59 . The disk filter 58 can also possibly be dispensed with, particularly if a filter element is arranged in the connecting line 18 or in the annular orifice 57 .
The sealing between the housing 51 and the cover 59 of the injection valve 50 is not limited to a sealing element 72 , for example an O-ring 73 , other alternatives here, for example, being to connect the cover 59 to the housing 51 by a cohesive material joint, for example by welding the cover 59 and the housing 51 together, or to connect them by positive interlock, for example by way of a sealing cone.
Alternatively, as shown in FIG. 3 , the pre-supply pump 23 may be connected by its delivery-side outlet 22 via the connecting line 17 to a variable restrictor 35 , which as restrictor element 34 is capable of limiting the volumetric flow 15 of the liquid 12 to the injection valve 50 through the connecting line 18 . Here the injection valve 50 is embodied as an inwardly opening injection valve 50 , the valve seat 53 in the housing 51 being closed by a valve ball 55 arranged between the closing member 61 and the valve seat 53 . In the case of the inwardly opening injection valve 50 , the valve spring 64 is positioned between the spring plate 65 of the closing member 61 and the insert 52 situated in the cover 59 , it being possible in all exemplary embodiments for the cover 59 to be integrally formed with the insert 52 . The embodiment of an inwardly opening injection valve 50 is not confined to the exemplary embodiment represented in FIG. 3 , having a variable restrictor 35 between the pre-supply pump 23 and the injection valve 50 , but may also be transferred to the other exemplary embodiments outlined. A cardanic action of the valve ball 55 obviates the need for a highly precise alignment of the closing member 61 in the insert 52 . A further advantage accrues from the fact that an inwardly opening injection valve 50 can be configured so that opening of the injection valve gives rise to a hydraulically acting closing force, which presses the valve ball 55 back into the valve seat 53 . It is thereby possible to keep a valve lift of the closing member 61 small, improving the facility for metering minute quantities of the liquid 12 . Alternatively the valve ball 55 may also be integrally connected to the closing member 61 .
In the exemplary embodiment sketched in FIG. 3 , the volumetric flow 15 to the injection valve 50 is limited in the initial state by the variable restrictor 35 , in such a way that a pressure below the threshold 28 is set in the liquid inlet 76 . Here, as it flows through the cooling circuit 75 , the liquid 12 does not increase the pressure, or increases it only to such a degree that the threshold is not reached and the valve ball 55 of the closing member 61 , which is pressed into the valve seat 53 by the spring force of the valve spring 64 , is not lifted from the valve seat 53 . In the initial state the liquid 12 therefore flows via the liquid return 77 and the return line 19 back to the reservoir 13 . If, from the initial state, the variable restrictor 35 is activated to open it, the volumetric flow 15 of the liquid 12 in the cooling circuit 75 of the injection valve is released in such a way that the further restrictor 66 in the closing member 61 limits the flow. As a result the pressure in the liquid inlet 76 rises above the threshold 28 , so that the spring force of the valve spring 64 is overcome and the injection valve 50 allows metering of the liquid 12 into the exhaust tract 20 . A narrowing of the restrictor 35 causes the pressure in the liquid inlet 76 to drop below the threshold 28 again, so that the injection valve 50 closes again. Alternatively the pressure in the liquid inlet 76 may dip below the threshold due to the metering of the liquid 12 , that the injection valve 50 closes.
In a further exemplary embodiment represented in FIG. 4 the restrictor element 34 between the pre-supply pump 23 and the injection valve 50 is embodied as an electrically controlled metering pump 41 .
The electrically controlled metering pump 41 comprises a pump housing 42 , in which a pressure chamber 49 is formed, in which a pressure can be built up by a pump piston 45 . The pump piston 45 is held in its initial position by a spring 46 , which is arranged between the pump housing 42 and a spring plate 47 formed on the pump piston 45 . The pump piston 45 additionally comprises an armature 44 integrally connected to the pump piston 45 , the armature 44 being capable of actuation by a solenoid assembly 43 , likewise arranged in the pump housing 42 . Branching off from the connecting line 17 between the pre-supply pump 23 and the electrically controlled metering pump 41 is a connecting line 37 , which is connected via a port 39 to a hydraulic working chamber 48 of the electrically controlled metering pump 41 . Here the hydraulic working chamber 48 comprises a spring chamber 85 and an armature chamber 84 , which are hydraulically connected to one another via a guide area 85 of the pump piston 45 formed in the pump housing 42 . An inlet restrictor 38 is arranged between the connecting line 17 and the pressure chamber 49 of the electrically controlled metering pump 41 . A non-return valve 36 arranged between the connecting line 17 and the pressure chamber 49 serves to prevent the liquid 12 flowing back out of the pressure chamber 49 to the pre-supply pump 23 . Here the non-return valve 36 is preferably arranged upstream of the inlet restrictor 38 in the direction of flow indicated by arrows in the figures.
In the unactivated state of the metering pump 41 , the pre-delivery pump 23 delivers the liquid 12 into the pressure chamber 49 of the electrically controlled metering pump 41 via the non-return valve 36 and the inlet restrictor 38 . Here the pressure of the pre-supply pump 23 is sufficient to overcome the spring force of the non-return valve 36 and to open the non-return valve 36 . When the metering pump 41 is not activated, the pump piston 45 is pressure-balanced, since the hydraulic working chamber 48 of the electrically controlled metering pump 41 is hydraulically connected to the pre-supply pump 23 via the connecting line 37 and the port 39 in the housing 42 . The pump piston 45 is positioned in its initial position by the spring 46 . In the unactuated initial state of the electrically controlled metering pump 41 the liquid 12 circulates, as described in the preceding exemplary embodiments, through the cooling circuit 75 of the injection valve 50 , thereby cooling the injection valve 50 . If the solenoid assembly 43 of the electrically controlled metering pump 41 is activated, the armature 44 is pulled up by the magnetic force of the solenoid assembly 43 , overcoming the spring force of the spring 46 and causing the pump piston 45 to move in the direction of the pressure chamber 49 . As a result the pressure in the pressure chamber 49 increases. The non-return valve 36 closes due to the pressure increase in the pressure chamber 49 , preventing the liquid 12 from flowing back into the reservoir 13 counter to the direction of flow. Due to the pressure increase in the pressure chamber 49 , the pressure in the liquid inlet 76 of the cooling circuit 75 also increases. If the pressure in the liquid inlet 76 reaches or exceeds the threshold, the injection valve 50 opens and allows metering of the liquid 12 into the exhaust tract 20 of the internal combustion engine 10 . Due to the injection, the pressure in the liquid inlet 76 is reduced, so that the pressure again falls below the threshold when the pump piston 45 of the electrically controlled injection valve 41 has reached its limit position and no further pressure is being built up in the pressure chamber 49 . When the energizing of the solenoid assembly 43 ceases, the pump piston 45 is returned to its initial position again by the spring 46 and the non-return valve 36 opens again, so that the pressure chamber 49 is again filled with liquid 12 .
Alternatively, instead of a magnetic circuit, which comprises the solenoid assembly 43 and the armature 44 , the electrically controlled metering pump 41 may also be controlled by a piezo-actuator. The invention is not limited to piston pumps; alternatively it is also possible to use other metering pumps 40 , for example diaphragm pumps or centrifugal pumps, which in the unactivated operating state restrict the volumetric flow 15 of the liquid 12 to the injection valve 50 and therefore allow a flow through the cooling circuit 75 in the injection valve 50 , and which in the activated state release the volumetric flow 15 of the liquid 12 to the injection valve, at least to a degree sufficient for the pressure in the liquid inlet 76 of the injection valve 50 to build up, at least until it reaches the threshold.
The device according to the invention is likewise not limited to electrically controlled metering pumps 41 but also encompasses metering pumps 40 , which are activated pneumatically, hydraulically or mechanically, for example.
As an alternative to pressure-balanced metering pumps, it is also possible to use metering pumps 40 in which, in the unactivated initial state, different pressures prevail in the hydraulic working chamber 48 and in the pressure chamber 49 , making it possible to dispense with the connecting line 37 and the port 39 in the pump housing 42 . As a further embodiment the pump piston 45 and the armature 44 may also be of two-part design. | The invention relates to a device and method for metering a liquid, in particular a fuel, into an exhaust gas tract of an internal combustion engine, wherein the device comprises at least one injection valve that can be closed by a closing member and that has cooling circuit for regulating the temperature in the injection valve, and wherein a throttle element is connected upstream of the injection valve to control, by closed loop or open loop, the quantity of a volume flow of the liquid through the injection valve, in particular through the cooling circuit of the injection valve, wherein the injection valve opens when the throttle element de-throttles the volume flow of the liquid to the injection valve. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to Provisional U.S. Pat. Appl. Ser. No. 60/736,204, filed Nov. 15, 2005, and entitled “Iterative Interference Cancellation Using Mixed Feedback Weights and Stabilizing Step Sizes,” which is incorporated by reference in its entirety.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates generally to iterative interference cancellation in received wireless communication signals and, more particularly, to cancellation of intra-cell interference and/or inter-cell interference in coded spread spectrum communication systems.
[0004] 2. Discussion of the Related Art
[0005] In an exemplary wireless multiple-access system, a communication resource is divided into code-space subchannels that are allocated to different users. A plurality of subchannel signals received by a wireless terminal (e.g., a subscriber unit or a base station) may correspond to different users and/or different subchannels allocated to a particular user.
[0006] If a single transmitter broadcasts different messages to different receivers, such as a base station in a wireless communication system broadcasting to a plurality of mobile terminals, the channel resource is subdivided in order to distinguish between messages intended for each mobile. Thus, each mobile terminal, by knowing its allocated subchannel(s), may decode messages intended for it from the superposition of received signals. Similarly, a base station typically separates received signals into subchannels in order to differentiate between users.
[0007] In a multipath environment, received signals are superpositions of time-delayed and complex-scaled versions of the transmitted signals. Multipath can cause several types of interference. Intra-channel interference occurs when the multipath time-delays cause subchannels to leak into other subchannels. For example, in a forward link, subchannels that are orthogonal at the transmitter may not be orthogonal at the receiver. When multiple base stations (or sectors or cells) are active, there may also be inter-channel interference caused by unwanted signals received from other base stations. Each of these types of interference can degrade communications by causing a receiver to incorrectly decode received transmissions, thus increasing a receiver's error floor. Interference may also have other deleterious effects on communications. For example, interference may lower capacity in a communication system, decrease the region of coverage, and/or decrease maximum data rates. For these reasons, a reduction in interference can improve reception of selected signals while addressing the aforementioned limitations due to interference.
[0008] These interferences take the following form when code division multiplexing is employed for a communication link, either with code division multiple access (as used in CDMA 2000, WCDMA, and related standards) or with time division multiple access (as used in EV-DO and related standards). A set of symbols is sent across a common time-frequency slot of the physical channel and separated using a set of distinct code waveforms, which are usually chosen to be orthogonal (or pseudo-orthogonal for reverse-link transmissions). The code waveforms typically vary in time, and these variations are introduced by a pseudo-random spreading code (PN sequence). The wireless transmission medium is characterized by a time-varying multipath profile that causes multiple time-delayed replicas of the transmitted waveform to be received, each replica having a distinct amplitude and phase due to path loss, absorption, and other propagation effects. As a result, the received code set is no longer orthogonal. The code space suffers from intra-channel interference within a base station as well as inter-channel interference arising from transmissions in adjacent cells.
[0009] The most basic receiver architecture employed to combat these various effects is the well-known Rake receiver. The Rake receiver uses a channel-tracking algorithm to resolve the received signal energy onto various multipath delays. These delayed signals are then weighted by the associated complex channel gains (which may be normalized by path noise powers) and summed to form a single resolved signal, which exploits some of the path diversity available from the multipath channel. It is well known that the Rake receiver suffers from a significant interference floor, which is due to both self-interference from the base station of interest (or base stations, when the mobile is in a soft-handoff base station diversity mode) and multiple-access interference from all base stations in the coverage area. This interference limits the maximum data rates achievable by the mobiles within a cell and the number of mobiles that can be supported in the cell.
[0010] Advanced receivers have been proposed to overcome the limitations of the Rake receiver. The optimal multi-user detector (MUD) has the best performance, but is generally too computationally complex to implement. MUD complexity increases exponentially with respect to the total number of active subchannels across the cell of interest and the interfering cells as well as the constellation size(s) of the subchannels. This complexity is so prohibitive that even efficient implementations based on the Viterbi algorithm cannot make it manageable in current hardware structures. Another approach is a properly designed linear receiver, which in many channel scenarios, is able to retain much of the optimal MUD performance, but with a complexity that is polynomial in the number of subchannels. The most common examples are the linear minimum mean squared error (LMMSE) receiver and the related decorrelating (or zero-forcing) receiver, which both require finding, or approximating, the inverse of a square matrix whose dimension is equal to the lesser between the number of active subchannels and the length (in samples) of the longest spreading code.
[0011] Complexity can still be prohibitive with these receivers, because such a matrix inverse needs to be calculated (or approximated) for each symbol. These receivers depend not only on the spectral characteristics of the multipath fading channel (which could be slowly time varying), but also on the time-varying spreading codes employed on the subchannels over each symbol. Thus, these receivers vary at the symbol rate even if the channel varies much more slowly.
[0012] An alternative approach currently under development for advance receivers sidesteps the need to invert a matrix for each symbol. It accomplishes this by employing a PN-averaged LMMSE (PNA-LMMSE) receiver that assumes the PN code is random and unknown at the receiver (at least for determining the correlation matrix). While this receiver is generally inferior to the LMMSE approach, it has the advantage of not having to be implemented directly, because it is amenable to adaptive (or partially adaptive) implementations. The advantages of an adaptive implementation over a direct implementation include reduced complexity and the fact that the additive noise power (i.e., background RF radiation specific to the link environment, noise in the receiver's RF front end, and any processing noise such as noise due to quantization and imperfect filtering) does not have to be estimated. However, these advantages incur the costs associated with adaptive filters (e.g., performance and adaptation rate). Note that a direct implementation without knowledge of the noise power modifies the LMMSE and PNA-LMMSE receivers into the corresponding decorrelating (or zero-forcing) receivers that arise from taking the background noise power to be zero when deriving the LMMSE and PNA-MMSE receivers.
[0013] Another method for further reducing complexity is to iteratively approximate the matrix-inverse functionality of the LMMSE receiver without explicitly calculating the inverse. Receivers of this type employ multistage interference cancellation. One particular type is known as parallel interference cancellation (PIC), and is motivated by well-known iterative techniques of quadratic minimization. In each stage of PIC, the data symbols of the subchannels are estimated. For each subchannel, an interference signal from the other subchannels is synthesized, followed by interference cancellation that subtracts the synthesized interference from each subchannel. The interference-cancelled subchannels are then fed to a subsequent PIC stage. Ideally, within just a few stages (i.e., before the complexity grows too large), the performance rivals that of the full linear receiver using a matrix inverse.
[0014] PIC can be implemented in various modes depending on what types of symbol estimates are used for interference cancellation. In a soft-cancellation mode, PIC does not exploit additional information inherent in the finite size of user constellations. That is, estimates of data symbols are not quantized to a constellation point when constructing interference signals. However, in some multiple-access schemes, the user constellations may be known (e.g., in an EV-DO link or in a WCDMA link without HSDPA users) or determined through a modulation classifier. In such cases, it is possible for PIC to be implemented in a hard-cancellation mode. That is, estimates of data symbols are quantized to constellation points (i.e., hard decisions) when constructing the interference signal.
[0015] In a mixed-cancellation mode, PIC employs a soft decision on each symbol whose constellation is unknown, and either a soft or hard decision on each symbol whose constellation is known, depending on how close the soft estimate is to the hard decision. Such a mixed-decision PIC typically outperforms both the soft-decision PIC and the hard-decision PIC. Moreover, it can also substantially outperform the optimal LMMSE receiver and promises even greater performance gains over PNA-LMMSE approaches currently under development for advanced receivers. The performance of soft-decision PIC is bounded by the optimal LMMSE.
SUMMARY OF THE INVENTION
[0016] In view of the foregoing background, embodiments of the present invention may provide a generalized interference-canceling receiver for canceling intra-channel and inter-channel interference in coded, multiple-access, spread-spectrum transmissions that propagate through frequency-selective communication channels. Receiver embodiments may employ a designed and/or adapted soft-weighting subtractive cancellation with a stabilizing step-size and a mixed-decision symbol estimator. Receiver embodiments may be designed, adapted, and implemented explicitly in software or programmed hardware, or implicitly in standard Rake-based hardware, either within the Rake (i.e., at the finger level) or outside the Rake (i.e., at the subchannel symbol level). Embodiments of the invention may be employed in user equipment on the forward link and/or in a base station on the reverse link.
[0017] Some embodiments of the invention address the complexity of the LMMSE approach by using a low-complexity iterative algorithm. Some embodiments of the invention in soft-mode may be configured to achieve LMMSE performance (as contrasted to the lesser-performing PNA-LMMSE) using only quantities that are easily measured at the receiver. Some embodiments address the sub-optimality of the LMMSE and PNA-LMMSE approaches by using an appropriately designed mixed-decision mode and may even approach the performance of an optimal multi-user detector. In some embodiments, stabilizing step sizes may be used to enhance stability of various PIC approaches. Some embodiments may employ symbol-estimate weighting to control convergence of various PIC approaches. Some embodiments of the invention address the limitation of various PIC approaches to binary and quaternary phase shift keying in mixed-decision mode by being configurable to any subchannel constellation. Some embodiments of the invention address the difficulty of efficiently implementing various PIC approaches in hardware by using a modified Rake architecture. Some embodiments of the invention address the so-called “ping-pong effect” (i.e., when the symbol error rate oscillates with iteration) in various PIC approaches by pre-processing with a de-biasing operation when making symbol estimates.
[0018] In one embodiment of the invention, an iterative interference canceller comprises a weighting means configured for applying at least one symbol weight to the input symbol decisions, a stabilizing step size means configured for applying a stabilizing step size to an error signal, and a mixed-decision processing means. The canceller is iterative, and thus, the weighting means, the stabilizing step size means, and the mixed-decision processing means are configured to perform processing during each of a plurality of iterations for each of the input symbol decisions.
[0019] The mixed-decision processing means may include, by way of example, but without limitation, a combination of hardware and software configured to produce soft and/or hard symbol estimates. The mixed-decision means comprises a de-biasing means configured for scaling the input symbol estimates with a scale factor to remove bias computed on the input symbol estimates, and a processing means configured for processing each de-biased input symbol estimate, irrespective of other symbol estimates. The processing means produces a hard decision that quantizes the de-biased input symbol estimate onto a nearby constellation point, or a soft decision that scales the de-biased input symbol estimate.
[0020] The stabilizing step size means may include, by way of example, but without limitation, any combination of hardware and software configured to scale an error signal with a scaling factor that may be used for controlling convergence in an iterative canceller. For example, the stabilizing step size means may include a signal processor configured to calculate at least one stabilizing step size and a multiplier for scaling an error signal with the step size. The multiplier means is configured for scaling (e.g., multiplying) an error signal with the stabilizing step size.
[0021] The step size calculation means may include, by way of example, but without limitation, software or programmable hardware configured for calculating a stabilizing step size.
[0022] The weighting means may include, by way of example, but without limitation, a weight-calculation means configured for producing symbol weights, and a multiplier configured for scaling symbol estimates by the weights.
[0023] Embodiments of the invention may be employed in any receiver configured to support one or more CDMA standards, such as (1) the “TIA/EIA-95-B Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System” (the IS-95 standard), (2) the “TIA/EIA-98-C Recommended Minimum Standard for Dual-Mode Wideband Spread Spectrum Cellular Mobile Station” (the IS-98 standard), (3) the standard offered by a consortium named “3rd Generation Partnership Project” (3GPP) and embodied in a set of documents including Document Nos. 3G TS 25.211, 3G TS 25.212, 3G TS 25.213, and 3G TS 25.214 (the WCDMA standard), (4) the standard offered by a consortium named “3rd Generation Partnership Project 2” (3GPP2) and embodied in a set of documents including “TR-45.5 Physical Layer Standard for cdma2000 Spread Spectrum Systems,” the “C.S0005-A Upper Layer (Layer 3) Signaling Standard for cdma2000 Spread Spectrum Systems,” and the “C.S0024 CDMA2000 High Rate Packet Data Air Interface Specification” (the CDMA2000 standard), (5) Multi-Code CDMA systems, such as High-Speed-Downlink-Packet-Access (HSDPA), and (6) other CDMA standards.
[0024] Receivers and cancellation systems described herein may be employed in subscriber-side devices (e.g., cellular handsets, wireless modems, and consumer premises equipment) and/or server-side devices (e.g., cellular base stations, wireless access points, wireless routers, wireless relays, and repeaters). Chipsets for subscriber-side and/or server-side devices may be configured to perform at least some of the receiver and/or cancellation functionality of the embodiments described herein.
[0025] These and other embodiments of the invention are described with respect to the figures and the following description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Embodiments according to the present invention are understood with reference to the schematic block diagrams of FIGS. 1 through 12 .
[0027] FIG. 1 is a general schematic illustrating an iterative interference canceller.
[0028] FIG. 2 is a block diagram illustrating a front-end processor for an iterative interference canceller.
[0029] FIG. 3 is a general schematic illustrating an interference cancellation unit (ICU).
[0030] FIG. 4 shows a weighting block in an ICU configured to separately process input symbol estimates corresponding to a plurality of base stations.
[0031] FIG. 5A is a block diagram illustrating part of an interference cancellation unit configured to synthesize constituent finger signals.
[0032] FIG. 5B is a block diagram illustrating part of an interference cancellation unit configured to synthesize constituent user signals.
[0033] FIG. 6A shows a cancellation block configured to perform interference cancellation on constituent signals, followed by Rake processing and despreading.
[0034] FIG. 6B shows a cancellation block configured to cancel interference in constituent signals, preceded by Rake processing and despreading.
[0035] FIG. 7 is a block diagram of the interference cancellation part of a subtractive canceller in which cancellation occurs prior to signal despreading.
[0036] FIG. 8A is a block diagram illustrating post interference-cancellation signal despreading on constituent finger signals.
[0037] FIG. 8B is a block diagram illustrating post interference-cancellation signal despreading on constituent user signals.
[0038] FIG. 9A is a block diagram showing a method for implicitly despreading a signal in a subtractive canceller that performs interference-cancellation prior to signal despreading.
[0039] FIG. 9B is a block diagram showing a method for explicitly despreading a signal in a subtractive canceller that performs interference-cancellation prior to signal despreading
[0040] FIG. 10 is a block diagram of a subtractive canceller configured to perform interference cancellation prior to signal despreading.
[0041] FIG. 11A is a block diagram illustrating an embodiment for implicitly calculating a stabilizing step size.
[0042] FIG. 11B is a block diagram illustrating how linear functions, such as despreading and generating a difference signal, can be swapped in an alternative embodiment for calculating a stabilizing step size.
[0043] FIG. 11C is a block diagram illustrating another embodiment for implicitly calculating a stabilizing step size.
[0044] FIG. 12 is a block diagram of a symbol-estimation block in an interference cancellation unit.
[0045] FIG. 13 is a block diagram of a dual feedback algorithm configured for implementing an iterative interference canceller.
[0046] Various functional elements or steps, separately or in combination, depicted in the figures may take the form of a microprocessor, digital signal processor, application specific integrated circuit, field programmable gate array, or other logic circuitry programmed or otherwise configured to operate as described herein. Accordingly, embodiments may take the form of programmable features executed by a common processor or discrete hardware unit.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
[0048] First the invention will be described as it applies to a forward-link channel, and then extended to include reverse-link channels. The following formula represents an analog baseband signal received at a mobile from multiple base stations, each with its own multipath channel,
y ( t ) = ∑ s = 0 B - 1 ∑ l = 0 L ( s ) α ( s ) , l ∑ k = 0 K ( s ) - 1 b ( s ) , k u ( s ) , k ( t - τ ( s ) , l ) + w ( t ) ,
t ∈ ( 0 , T ) , Equation 1
with the following definitions
(0,T) is the symbol interval; B is the number of modeled base stations and is indexed by the subscript (s) which ranges from (0) to (B−1); here, and in the sequel, the term “base stations” will be employed loosely to include cells or sectors; L (s) is the number of resolvable (or modeled) paths from base station (s) to the mobile; α (s),l and τ (s),l are the complex gain and delay, respectively, associated with the l-th path of base station (s); K (s) is the number of active users or subchannels in base station (s) that share a channel via code-division multiplexing; these users or subchannels are indexed from 0 to K (s) −1; u (s),k (t) is a code waveform (e.g., spreading waveform) of base station (s) used to carry the k th user's symbol for that base station (e.g., a chip waveform modulated by a user-specific Walsh code and covered with a base-station specific PN cover); b (s),k is a complex symbol transmitted for the k th user or subchannel of base station (s); and w(t) is zero-mean complex additive noise that contains both thermal noise and any interference whose structure is not explicitly modeled (e.g., inter-channel interference from unmodeled base stations and/or intra-channel interference from unmodeled paths).
[0057] Typically, a user terminal (e.g., a handset) is configured to detect only symbols transmitted from its serving base station (e.g., the symbols from base station ( 0 )) or a subset thereof (e.g., symbols for the k th user of base station ( 0 )). Interference can impede the determination of b (s),k from y(t). Not only is additive noise w(t) present, but there may be intra-channel and inter-channel interference.
[0058] Intra-channel interference typically occurs when multiple users are served by a given base station (i.e., a serving base station). Even if the users' transmitted code waveforms are orthogonal, multipath in the transmission channel causes the codes to lose their orthogonality. Inter-channel interference is caused by transmissions from non-serving base stations whose signals contribute to the received baseband signal y(t).
[0059] FIG. 1 is a block diagram of an iterative interference canceller (IIC), which is a low-complexity receiver configured to mitigate intra-channel and inter-channel interference. The received baseband signal y(t) is input to a front-end processor 101 , which produces initial symbol estimates for all symbols of the active users served by at least one base station. The initial symbol estimates are coupled to a first interference cancellation unit (ICU) 102 configured to cancel a portion of the intra-channel and inter-channel interference that corrupts the symbol estimates. The ICU 102 outputs a first set of updated symbol estimates, which are interference-cancelled symbol estimates. The updated symbol estimates are coupled to a second ICU 103 . A plurality M of ICUs 102 - 104 illustrate an iterative process for performing interference cancellation in which the initial symbol estimates are updated M times.
[0060] FIG. 2 is a block diagram of the front-end processor 101 shown in FIG. 1 . Each of a plurality B of Rake-based receiver components 201 - 203 provides estimates of symbols transmitted from a corresponding base station. The detailed block diagram depicted in Rake receiver 202 represents the functionality of each of the components 201 - 203 . Rake receiver 202 , corresponding to an s th base station 202 , includes a plurality L (s) of delay elements 210 - 211 configured to advance the received baseband signal y(t) in accordance with multipath-delay quantities {τ (s),l } l=0 L (s) −1 . The advanced signals are scaled 212 - 213 by corresponding path gains {α (s),l } l=0 L (s) −1 prior to combining 214 to produce a combined signal of the form
∑ l = 0 L ( s ) - 1 α ( s ) , l * α _ ( s ) y ( t + τ ( s ) , l ) ,
where
α _ ( s ) = ( ∑ l = 0 L ( s ) - 1 α ( s ) , l 2 ) 1 / 2
is the Euclidean norm of the path-gain vector,
α (s) =└α (s),0 α (s),1 . . . α (s),L (s) −1 ┘ T , and the superscript T denotes the matrix transpose operator.
[0061] The combined signal is resolved onto the users' code waveforms by correlative despreading, which comprises multiplying 215 - 216 the combined signals by complex conjugates of each code waveform, followed by integrating 217 - 218 the resultant products. A despread signal corresponding to a k th code waveform is
q ( s ) , k ≡ 1 α _ ( s ) 2 ∫ 0 T u ( s ) , k * ( t ) ∑ l = 0 L ( s ) - 1 α ( s ) , l * y ( t + τ ( s ) , l ) ⅆ t . Equation 2
This value is also referred to as a Rake front-end soft estimate of the symbol b (s),k . Since Rake processing, combining, and despreading are linear operations, their order may be interchanged. Thus, alternative embodiments may be provided in which the order of the linear operations is changed to produce q (s),k .
[0062] A symbol estimator comprises scaling blocks 219 - 220 and function blocks 221 - 222 , which are configured to refine the estimates q (s),k into front-end symbol estimates {circumflex over (b)} (s),k [0] of the transmitted data symbols b (s),k . Each of the functions depicted in FIG. 2 may be configured to process discrete-time sequences. For example, time advances 210 - 211 (or delays) may be implemented as shifts by an integer number of samples in discrete-time sequences, and integration 217 - 218 may employ summation.
[0063] FIG. 3 is a block diagram of an i th ICU comprising four functional blocks. A weighting module 301 calculates and applies soft weights to input symbol estimates. A synthesizing module 302 processes weighted symbol estimates to synthesize constituent signals of an estimated received signal. For example, the estimated received signal y(t) is a sum of the constituent signals, each of which is synthesized from the weighted symbol estimates. The synthesized constituents are processed in a canceller 303 (such as a subtraction module) configured to produce interference-cancelled signals having reduced intra-channel and inter-channel interferences. The canceller 303 also includes a resolving module (not shown) configured to resolve the interference-cancelled signals onto user code waveforms to produce resolved signals. A mixed-decision module 304 processes the resolved signals to produce updated symbol estimates.
[0064] FIG. 4 shows a weighting module (such as weighting module 301 ) configured to separately process input symbol estimates corresponding to a plurality B of base stations. A plurality of scaling modules 401 - 403 scale the input symbol estimates. Scaling module 402 depicts detailed functionality for processing signals from an exemplary s th base station. Similar details are typically present in each of the scaling modules 401 - 403 .
[0065] A plurality K (s) of symbol estimates {{circumflex over (b)} (s),k [1] } k=0 K (s) −1 of transmitted symbols {b (s),k } k=0 K (s) −1 produced by an i th ICU is input to scaling module 402 . The symbol estimates are multiplied 410 - 411 by corresponding complex weights {γ (s),k [i] } k=0 K (s) −1 to produce weighted symbol estimates {γ (s),k [i] {circumflex over (b)} (s),k [i] } k=0 K (s) −1 . The magnitude of weight γ (s),k [i] may be calculated with respect to a merit of the corresponding symbol estimate {circumflex over (b)} (s),k [i] .
[0066] The soft weights can be regarded as a confidence measure related to the accuracy of a decision, or symbol estimate. For example, a high confidence weight relates to a high certainty that a corresponding decision is accurate. A low confidence weight relates to a low certainty. Since the soft weights are used to scale decisions, low-valued weights reduce possible errors that may be introduced into a calculation that relies on symbol estimates.
[0067] In one embodiment of the invention, the weights γ (s),k [i] may be derived from at least one signal measurement, such as SINR. Clearly, the larger the SINR, the greater the reliability of the corresponding symbol estimate. For example, the weights γ (s),k [i] may be expressed by
γ ( s ) , k [ i ] = max { C ( s ) , k , 1 1 + 1 / SINR ( s ) , k [ i ] } , Equation 3
where SINR (s),k [i] is a ratio of average signal power to interference-plus-noise power of a k th user in base station (s) after the i th ICU, and C k is a non-negative real constant that can be used to ensure some feedback of a symbol estimate, even if its SINR is small. Note that, as the SINR grows large, the weight tends toward unity, meaning that the estimate is very reliable.
[0068] The SINR (and thus, the soft weights) may be evaluated using techniques of statistical signal processing, including techniques based on an error-vector magnitude (EVM). Alternatively, a pilot-assisted estimate of the broadband interference-plus-noise floor, together with a user specific estimate of the signal-plus-interference-plus-noise floor, may be used to estimate the SINR values.
[0069] In another embodiment of the invention, the weights γ (s),k [i] may be expressed as a function of symbol estimates {circumflex over (b)} (s),k [i] , such as shown in the following equation
γ ( s ) , k [ i ] = Re { E [ slice ( b ^ ( s ) , k [ i ] ) * b ^ ( s ) , k [ i ] ] } E [ b ^ ( s ) , k [ i ] 2 ] , Equation 4
where Re{} returns the real part of the argument. The statistical expectations E[ ] in the numerator and denominator can be estimated, for example, via time-series averaging. The term slice({circumflex over (b)} (s),k [i] ) represents the symbol estimate {circumflex over (b)} (s),k [i] sliced (i.e., quantized) to the nearest constellation point from which the symbol b (s),k was drawn. This approach is applicable for symbols with known constellations. For example, it is typical for a receiver to know the symbol constellation for a user of interest, but it may not know which constellations are assigned to other users.
[0070] In this embodiment, the weights γ (s),k [i] are a function of a symbol estimate's {circumflex over (b)} (s),k [i] proximity to a given constellation point. Thus, a symbol estimate {circumflex over (b)} (s),k [i] that is close to a constellation point is provided with a large weight indicative of a high confidence measure in the symbol estimate's accuracy. For example, if the value {circumflex over (b)} (s),k [i] is a hard-decision estimate of b (s),k (i.e., it is quantized to the nearest constellation point), then its associated weight is γ (s),k [i] =1, which indicates a high degree of confidence in the symbol estimate.
[0071] In some embodiments, both Equation 3 and Equation 4 may be used in a receiver to calculate soft weights. Some embodiments of the invention may provide for subset selection to force one or more of the weights to zero. Such embodiments may be expressed as adaptations to Equation 3 and/or Equation 4 expressed by
γ (s),k [i] =0 for some subset of the users. Equation 5
Forcing the weights of some users to zero effectively restricts which user signals are employed for interference cancellation. Some embodiments may provide for canceling only a predetermined number P of strongest users (e.g., users having the largest weight values). The number P may be fixed for all iterations, or it may vary with respect to iteration. In some embodiments, the number P may range from zero (i.e., no interference cancellation) to
K ≡ ∑ s = 0 B - 1 K ( s )
(i.e., interference of all users cancelled). In some embodiments, the weights of user signals transmitted from at least one weakest base station are set to zero.
[0072] FIG. 5A is a block diagram of a synthesizing module (such as the synthesizing module 302 ) in which the constituent signals are associated with each Rake finger. Each of a plurality B of synthesizing modules 501 - 503 is assigned to one of a plurality B of base stations. A block diagram for an exemplary synthesizing module 502 corresponding to a base station (s) depicts details that are common to all of the synthesizing modules 501 - 503 .
[0073] Weighted symbol estimates γ (s),k [i] {circumflex over (b)} (s),k are modulated 510 - 511 onto corresponding code waveforms u (s),k (t) to produce a plurality K (s) of coded waveforms, which are combined in combining module 512 to produce a synthesized transmission signal
∑ k = 0 K ( s ) - 1 γ ( s ) , k [ i ] b ^ ( s ) , k [ i ] u ( s ) , k ( t ) .
Channel emulation (including delaying the synthesized transmission 513 - 514 by τ (s),l and scaling 515 - 516 with channel gains α (s),l ) is performed to produce constituent signals corresponding to each finger. A synthesized constituent signal for an l th finger of base station (s) is
y ~ ( s ) , l [ i ] ≡ α ( s ) , l ∑ k = 0 K ( s ) - 1 γ ( s ) , k [ i ] b ^ ( s ) , k [ i ] u ( s ) , k ( t - τ ( s ) , l ) . Equation 6
When all of the finger constituents are summed, the result is
y ~ [ i ] ( t ) ≡ ∑ s = 0 B - 1 ∑ l = 0 L ( s ) - 1 y ~ ( s ) , l [ i ] ( t ) , Equation 7
which is an estimate of the signal that would be received at the mobile if the base stations were to transmit the weighted symbols.
[0074] FIG. 5B is a block diagram of a synthesizing module (such as the synthesizing module 302 ) in which the constituent signals are associated with each user in the system. Each synthesizing module 521 - 523 is configured to emulate multipath channels for all base stations. Synthesizing module 522 includes a block diagram that is indicative of the functionality of each of the synthesizing module 521 - 523
[0075] In synthesizing module 522 , a plurality K (s) of modulators (such as modulator 531 ) modulates each weighted symbol γ (s),k [i] {circumflex over (b)} (s),k onto a corresponding code waveform u (s),k (t). Each modulated code waveform is processed by a bank of finger delay elements 532 - 533 and channel gain scaling elements 534 - 535 corresponding to the multipath channel of base station (s). The resulting emulated multipath components are combined in combining module 536 to produce an estimated received signal for a k th user of base station (s),
y ~ ( s ) , k [ i ] ≡ ∑ l = 0 L ( s ) - 1 α ( s ) , l γ ( s ) , k [ i ] b ^ ( s ) , k [ i ] u ( s ) , k ( t - τ ( s ) , l ) . Equation 8
The subscript k on the left-hand side denotes that the constituent signal is for a user k, whereas the subscript l on the left-hand side of Equation 6 represents that the constituent signal is for a finger l. The sum of the user constituent signals produces a synthesized received signal
y ~ [ i ] ( t ) ≡ ∑ s = 0 B - 1 ∑ k = 0 K ( s ) - 1 y ~ ( s ) , k [ i ] ( t ) . Equation 9
The left-hand sides of Equation 7 and Equation 9 are the same signal, whereas the right-hand sides are simply two different decompositions.
[0076] FIG. 6A shows a cancellation module 601 (such as the canceller 303 in FIG. 3 ) configured to perform interference cancellation 610 on constituent signals, followed by Rake processing and despreading 611 in a Rake-based receiver. FIG. 6B shows a cancellation module 602 configured to synthesize 621 a received signal from constituent components, followed by Rake processing and despreading 622 , and interference cancellation 623 .
[0077] FIG. 7 is a block diagram of an interference canceller comprising a plurality B of cancellers 701 - 703 configured to perform interference cancellation on a plurality J of constituent signals for each of a plurality B of base stations. Since the constituent signals may be either fingers or users, index jε{0, 1, . . . , J (s) −1γ is expressed by
J ( s ) = { L ( s ) for finger constituets K ( s ) for user constituets .
[0078] Canceller 702 includes a block diagram that represents the functionality of each of the cancellers 701 - 703 . The constituent signals corresponding to each base station are summed in a combining module 711 to produce a synthesized received signal,
y ~ ( s ) [ i ] ≡ ∑ j = 0 J ( s ) - 1 y ~ ( s ) , j [ i ] ,
where {tilde over (y)} (s),j [i] is j th constituent signal (either finger or user) for base station (s). A plurality B of these sums corresponding to different base stations are combined in combining module 721 to produce a synthesized receive signal
y ~ [ i ] ( t ) = ∑ s = 0 B - 1 y ~ ( s ) [ i ] ( t ) .
The synthesized receive signal is subtracted from the actual received signal in a subtraction module 722 to produce a residual signal y(t)−{tilde over (y)} [i] (t) . A stabilizing step size module 723 scales the residual signal by a complex stabilizing step size μ [i] to produce a scaled residual signal μ [i] (y(t)−{tilde over (y)} [i] (t)). The scaled residual signal is combined with the constituent signals {tilde over (y)} (s),j [i] in combining modules 712 - 714 to produce a set of interference-cancelled constituents represented by
z (s),j [i] ( t )≡ {tilde over (y)} (s),j [i] ( t )+μ [i] ( y ( t )− {tilde over (y)} [i] ( t )), Equation 10
where z (s),j [i] (t) is an interference-cancelled j th constituent signal for base station (s).
[0079] In an alternative embodiment, cancellation may be performed with only a subset of the constituent channels. In each base station, only those constituent signals being used for cancellation may be used to synthesize the estimated receive signal for base station (s). Thus, {tilde over (y)} (s) [i] becomes
y ~ ( s ) [ i ] ≡ ∑ j ∈ J ( s ) y ~ ( s ) , j [ i ] where J ( s ) ⊆ { 0 , 1 , … , J ( s ) - 1 }
are indices of the subset of constituent signals to be employed in cancellation. Embodiments of the invention may be configured for applications in which hardware limitations restrict the number of finger signals or user signals that can be used for interference cancellation (e.g., only the strongest constituents are used).
[0080] The interference-cancelled signals produced by the canceller shown in FIG. 7 may be processed by a Rake despreader shown in FIG. 8A , which is configured for processing finger inputs. Specifically, finger signals associated with each base station are input to corresponding fingers of a Rake despreading module tuned to that base station. A Rake despreading module 802 tuned to an s th base station comprises a block diagram indicating the functionality of a plurality B of Rake despreading modules 801 - 803 .
[0081] Interference cancelled signals z (s),l [i] (t) are time-advanced 810 - 811 by an amount τ (s),l . A maximal ratio combining module scales 812 - 813 each time-advanced signal z (s),l [i] (t+τ (s),l ) by α (s),l */∥ α (s) ∥ and combines 814 the time-advanced signals for each base station. A resolving module comprising multipliers 815 - 816 and integrators 817 - 818 resolves each combined signal
1 α _ ( s ) ∑ l = 0 L ( s ) - 1 α ( s ) , k * z ( s ) , l [ i ] ( t + τ ( s ) , l )
onto code waveforms associated with base station (s) via correlative despreading. The resulting quantity for a k th user of base station (s) is denoted by
b ~ ( s ) , k [ i ] = 1 α _ ( s ) 2 ∫ 0 T u ( s ) , k * ( t ) ∑ l = 0 L ( s ) - 1 α ( s ) , k * z ( s ) , l [ i ] ( t + τ ( s ) , l ) . Equation 11
[0082] FIG. 8B is a block diagram of a Rake despreader configured for processing interference-cancelled signals relating to user inputs. In this case, the input constituent signals are user signals. A Rake despreading module 822 tuned to an s th base station comprises a block diagram indicating functional details that are common to a plurality B of Rake despreading modules 821 - 823 .
[0083] Interference cancelled signals z (s),k [i] (t) corresponding to a k th user and s th base station are processed by a plurality L (s) of time-advance modules 831 - 832 corresponding to the multipath channel for the s th base station. The resulting time-advanced signals {z (s),k [i] (t+τ (s),l )} l=0 L (s) −1 are weighted by a plurality of weighting modules 833 - 834 , and the weighted signals are combined in combiner 835 . A resolving module comprising multiplier 836 and integrator 837 resolves the combined signal onto the k th user's code waveform to give
b ~ ( s ) , k [ i ] = 1 α _ ( s ) 2 ∫ 0 T u ( s ) , k * ( t ) ∑ l = 0 L ( s ) - 1 α ( s ) , l * z ( s ) , k [ i ] ( t + τ ( s ) , l ) . Equation 12
The values of {tilde over (b)} (s),k [i] shown in Equation 11 and Equation 12 are generally not the same value, since the value of {tilde over (b)} (s),k [i] in Equation 11 is produced by cancellation employing finger constituents, whereas {tilde over (b)} (s),k [i] expressed by Equation 12 is produced by cancellation employing user constituents.
[0084] FIG. 9A is a block diagram of a Rake despreader, such as Rake despreaders 611 and 622 shown in FIGS. 6A and 6B , respectively. The Rake despreader comprises a plurality B of Rake despreading modules 901 - 903 , each configured to process constituent signals from one of a plurality B of base stations. An exemplary Rake despreader module 902 is a block diagram illustrating functionality of each of the Rake despreader modules 901 - 903 .
[0085] Input constituent signals {tilde over (y)} (s),j [i] (t) for all values of j are subtracted 911 from the received signal y(t) to produce a difference signal, or error signal, representing the difference between the received signal and the synthesized estimates of signals received by the base stations. For base station (s), the difference signal is y(t)−{tilde over (y)} (s) [i] (t), where
y ~ ( s ) [ i ] ( t ) ≡ ∑ j = 0 J ( s ) - 1 y ~ ( s ) , j [ i ] ( t ) .
The difference signal for base station (s) is processed by a parallel bank of time advance modules 912 - 913 associated with the multipath channel for that base station, followed by maximal-ratio combining. In this embodiment, a maximal-ratio combining module is configured to perform weighting 914 - 915 and combining 916 . A resolving module comprising multipliers 917 - 918 and integrators 919 - 920 resolves the resulting combined signals onto code waveforms of the base station's users to give the difference signal vector, or error signal vector, q (s),k −{tilde over (q)} (s),k [i] , where
q ~ ( s ) , k [ i ] = 1 α _ ( s ) 2 ∫ 0 T u ( s ) , k * ( t ) ∑ l = 0 L ( s ) - 1 α ( s ) , l * z ( s ) [ i ] ( t + τ ( s ) , l ) Equation 13
and z (s) [i] (t) was defined in Equation 10.
[0086] Rake despreading, such as described with respect to the exemplary Rake despreading module 902 , may also be accomplished explicitly by employing matrix multiplication to synthesize constituent signals of the received signal, such as represented by block 931 shown in FIG. 9B .
[0087] A diagonal soft-weighting matrix may be defined as
Γ [i] =diag(γ (0),0 [i] , . . . , γ (0),K (0) −1 [i] | . . . |γ (B−1),0 [i] , . . . , γ (B−1),K (B−1) −1 [i] ), Equation 14
in which all of the users' soft weights are ordered first by base station and then by users within a base station. The same indexing may also be used to express the column vector of symbol estimates input to an i th ICU as
{circumflex over (b)} [i] =[{circumflex over (b)} (0),0 [i] , . . . , {circumflex over (b)} (0),K (0) −1 [i] | . . . |{circumflex over (b)} (B−1),0 [i] , . . . , {circumflex over (b)} (B−1),K (B−1) −1 [i] ] T . Equation 15
[0088] The weighted symbol estimates are expressed as Γ [i] b [i] , and the outputs of the Rake despreading modules 901 - 903 are expressed by the difference equation,
q − {tilde over (q)} [i] = q −RΓ [i] b [i] , Equation 16
where,
q =[q (0),0 , . . . , q (0),K (0) −1 | . . . |q (B−1),0 , . . . , q (B−1),K (B−1) −1 ] T Equation 17
and
{tilde over (q)} [i] =[{tilde over (q)} (0),0 [i] , . . . , {tilde over (q)} (0),K (0) −1 [i] | . . . |{tilde over (q)} (B−1),0 [i] , . . . , {tilde over (q)} (B−1),K (B−1) −1 [i] ] T . Equation 18
The values of q [i] represent the despread signals, such as described with respect to FIG. 2 . The values of {tilde over (q)} [i] are represented by Equation 13, and R is a square matrix whose elements are correlations between the users' received code waveforms. In FIG. 9B , the functionality expressed by Equation 16 is implemented via the matrix-multiplication block 931 and a subtraction module 932 .
[0089] A global index κε{0, 1, . . . , K−1} with
K ≡ ∑ s = 0 B - 1 K ( s )
is employed for ordering users (first by base station, and then by users within a base station) described with respect to Equation 14. Thus, κ=0 corresponds to a first user (denoted by index zero) of a first base station (denoted by an index zero), and κ=K corresponds to a last user (denoted by index K (B−1) −1) of a last base station (denoted by index (B−1) ). If a user κ is a member of base station (s) and a user κ′ is a member of base station (s′), then the (κ, κ′) element of matrix R may be expressed by
R κκ ′ = 1 α _ ( s ) α _ ( s ′ ) ∫ ∑ l = 0 L ( s ) - 1 α ( s ) , l u κ ( t - τ ( s ) , l ) ∑ l ′ = 0 L ( s ′ ) - 1 α ( s ′ ) , l ′ * u κ ′ * ( t - τ ( s ′ ) , l ′ ) ⅆ t . Equation 19
Thus, the elements of R can be built at the receiver with estimates of the path gains, path delays, and knowledge of the users' code waveforms.
[0090] FIG. 10 is a block diagram of an interference canceller, such as the interference-cancellation block 623 shown in FIG. 6 . The difference signal q (s),k −{tilde over (q)} (s),k [i] is scaled with a stabilizing step size μ (i) by a stabilizing step size module 1001 , which may include a calculation module (not shown) configured to calculate a stabilizing step size having a magnitude that is a function of proximity of input symbol decisions to a desired interference-cancelled symbol decision. The resulting scaled difference signal is summed 1003 with a product 1002 of the weighted symbol estimates Γ [i] {circumflex over (b)} [i] and a K×K implementation matrix F to yield
{tilde over (b)} [i+1] =FΓ [i] {circumflex over (b)} [i] +μ [i] ( q − {tilde over (q)} [i] ). Equation 20
[0091] The choice of F allows interference cancellation after despreading to mimic interference cancellation prior to despreading for either user constituents or finger constituents. For user constituents, F=I. For finger constituents, F is a block-diagonal matrix with a plurality B of diagonal blocks, wherein an s th diagonal block is a K (s) ×K (s) block representing the users' transmit correlation matrix for base station (s). The (k,k′) element of the s th diagonal block (denoted by F (s)(s) ) is equal to
( F (s)(s) ) kk′ =ιu (s),k ( t ) u (s),k′ *( t ) dt. Equation 21
[0092] The stabilizing step size μ [i] may be used to enhance interference cancellation in each ICU and/or stabilize iterative interference cancellation. A quality metric of a canceller's output {tilde over (b)} [i+1] may be derived as follows. If it is known (or approximated) that the additive noise w(t) in Equation 1 is Gaussian, then the despread outputs q , conditional on the transmitted symbols
b =[b (0),0 , . . . , b (0),K (0) −1 | . . . |b (B−1),0 , . . . , b (B−1),K (B−1) −1 ] T , Equation 22
are jointly complex normal random variables with mean R b and covariance Γ [i] R (i.e., q | b is distributed as CN(R b ; R)). If it is approximated that q | {tilde over (b)} [i+1] is distributed as CN(R {tilde over (b)} [i+1] ; R), where {tilde over (b)} [i+1] and its dependence on μ [i] are given by Equation 20, then the value of μ [i] that gives the maximum-likelihood soft estimate for {tilde over (b)} [i+1] is
μ [ i ] = ( q _ - RF Γ [ i ] b ^ _ [ i ] ) H ( q _ - R Γ [ i ] b ^ _ [ i ] ) ( q _ - R Γ [ i ] b ^ _ [ i ] ) H R ( q _ - R Γ [ i ] b ^ _ [ i ] ) . Equation 23
Alternatively, the value of μ [i] that gives the maximum-likelihood soft estimate for Γ [i] {tilde over (b)} [i+1] is
μ [ i ] = ( q _ - R Γ [ i ] F Γ [ i ] b ^ _ [ i ] ) H Γ [ i ] ( q _ - R Γ [ i ] b ^ _ [ i ] ) ( q _ - R Γ [ i ] b ^ _ [ i ] ) H ( Γ [ i ] ) H R Γ [ i ] ( q _ - R Γ [ i ] b ^ _ [ i ] ) . Equation 24
[0093] Different formulations of the step-size may be used within the same IIC. For example, a step size based on Equation 24 may be used in a sequence of ICUs and Equation 24 may be used in the last ICU of the sequence. The Equations 23 and 24 may be adapted for cases in which there is no soft weighting (i.e., when Γ [i] =I). Similarly step-size equations may be adapted when constituent user signals are employed (i.e., F=I). Furthermore, Equation 23 and Equation 24 may be determined implicitly whenever F=I, or when F is approximated as I. Since F contains the users' correlation matrices at the transmitter for each base station as its block diagonal, it will approximately equal identity, as the users' code waveforms are typically designed to be mutually orthogonal (or quasi-orthogonal for the reverse link). Any non-orthogonality is due to the finite duration of the pulse-shaping filters that approximate their infinite-duration theoretical counterparts. In this case, Equation 23 becomes
μ [ i ] = ( q _ - R Γ [ i ] b ^ _ [ i ] ) H ( q _ - R Γ [ i ] b _ ^ [ i ] ) ( q _ - R Γ [ i ] b _ ^ [ i ] ) H R ( q _ - R Γ [ i ] b _ ^ [ i ] ) . Equation 25
[0094] FIG. 11A illustrates a method and apparatus for calculating a stabilizing step size. A Rake receiver 1100 comprises a first Rake, maximal ratio combining, and despreading unit 1101 to process a received signal y(t) for producing an output despread signal vector q . A second Rake, maximal ratio combiner, and despreader unit 1102 processes a synthesized receive signal with weighted symbol estimates corresponding to an i th iteration, and represented by
y ~ [ i ] ( t ) = ∑ s = 0 B - 1 ∑ l = 0 L ( s ) - 1 α ( s ) , l ∑ k = 0 K ( s ) - 1 γ ( s ) , k [ i ] b ^ ( s ) , k [ i ] u ( s ) , k ( t - τ ( s ) , l ) ,
to produce an estimated received signal RΓ [i] {tilde over (b)} [i] .
[0095] A combiner 1103 calculates the difference between the outputs of 1101 and 1102 to produce a difference signal, or error signal, β [i] ≡ q −RΓ [i] b [i] , whose elements are indexed first by base station, and then by users within a base station,
β [i] =[β (0),0 [i] , . . . , β (0),K (0) −1 [i] | . . . |β (B−1),0 [i] , . . . , β (B−1),K (B−1) −1 [i] ] T .
Alternatively, since the operations used to produce β [i] are linear, a difference signal y(t)−{tilde over (y)} (s) [i] (t) may be produced prior to despreading, such as shown by block 1110 in FIG. 11B .
[0096] The norm-square of β [i] (i.e., ∥ β [i] ∥ 2 ) is evaluated 1104 to generate the numerator in Equation 25. The elements of β [i] are processed 1105 to produce a synthesized received signal
∑ s = 0 B - 1 ∑ l = 0 L - 1 α ( s ) , l ∑ k = 0 K - 1 β ( s ) , k [ i ] u ( s ) , k ( t - τ ( s ) , l ) ,
and the norm square of this signal is calculated 1106 to produce the denominator of Equation 25.
[0097] FIG. 11C is a block diagram of a method and apparatus for implicitly calculating a stabilizing step size for the special case of F=I. In this case, Equation 24 becomes
μ [ i ] = ( q _ - R ( Γ [ i ] ) 2 b _ ^ [ i ] ) H Γ [ i ] ( q _ - R Γ [ i ] b _ ^ [ i ] ) ( q _ - R Γ [ i ] b _ ^ [ i ] ) H ( Γ [ i ] ) H R Γ [ i ] ( q _ - R Γ [ i ] b _ ^ [ i ] ) , Equation 26
The signal β [i] is generated by a Rake, maximal ratio combining, and despreading unit 1120 and multiplied 1121 by Γ [i] to produce vector Γ [i] β [i] . A synthesis module 1122 processes the vector Γ [i] β [i] to produce a synthesized receive vector, which is norm-squared 1123 to produce the denominator of Equation 26.
[0098] A synthesized received signal is generated 1124 from the vector (Γ [i] ) 2 β [i] and processed with received signal y(t) by an adder 1125 to produce a difference signal. A Rake/combiner/despreader 1126 processes the difference signal to generate the vector q −R(Γ [i] ) 2 {circumflex over (b)} [i] . The inner product 1127 between this vector and the vector Γ [i] β [i] gives the numerator of Equation 26.
[0099] In an alternative embodiment, the stabilizing step size may be derived from the multipath channel gains,
μ [ i ] = μ = max { C , ( max ( s ) , l α ( s ) , l p ∑ s = 0 B - 1 ∑ l = 0 L ( s ) - 1 α ( s ) , l p ) } , Equation 27
where μ [i] is fixed for every ICU and C, p and r are non-negative constants.
[0100] FIG. 12 is a block diagram of a symbol-estimation block comprising a plurality B of mixed-decision modules 1201 - 1203 configured to process signals received from B base stations. Mixed-decision module 1202 shows functionality that is common to all of the mixed-decision modules 1201 - 1203 . De-biasing modules 1210 - 1211 scale each of a plurality K (s) of input symbol estimates {tilde over (b)} (s),k [i+1] with a non-negative de-biasing constant d (s),k [i] for producing de-biased input symbol estimates. The mixed-decision module 1202 includes symbol-estimation modules 1212 - 1213 configured to perform symbol estimation on de-biased input symbol estimates whose constellations are known at the receiver.
[0101] The de-biasing constant may be expressed by
d (s),k [i] =E[|b (s),k |]/E└|{tilde over (b)} (s),k [i+1] |┘ Equation 28
d (s),k [i] =√{square root over (E[|b (s),k | 2 ·]/E[|{tilde over (b)} (s),k [i+1] | 2 ])} Equation 29
d (s),k [i] =1 if the symbol constellation is unknown, Equation 30
where the statistical expectations may be approximated by time-averaging. De-biasing helps mitigate the “ping-pong” phenomenon often associated with iterative interference cancellation in which the symbol error rate oscillates with respect to iterations. After de-biasing, each value d (s),k [i] {tilde over (b)} (s),k [i+1 is operated on by a map Ψ (s),k that takes the input into the complex plane to yield the updated symbol estimate
{circumflex over (b)} (s),k [i+1] =Ψ (s),k ( d (s),k [i] {tilde over (b)} (s),k [i+1] ). Equation 31
[0102] The map Ψ (s),k may be a mixed-decision map, which is a combination of soft and hard decisions. A soft-decision map is provided by a function Ψ (s),k (x) that is a continuous function whose output ranges over the complex plane. Common examples, include, but are not limited to,
Ψ ( s ) , k soft ( x ) = { c ( s ) , k x or c ( s ) , k ( tanh ( a ( s ) , k Re { x } ) + - 1 tanh ( a ( s ) , k Im { x } ) ) Equation 32
for positive real-valued constants a (s),k and c (s),k . The expression Re{•} returns the real part of its argument, and Im{•} returns the imaginary part of its argument. A hard-decision map is provided when Ψ (s),k (x) slices the input so that the output is an element from the complex symbol constellation employed by the k th user of base station (s),
Ψ (s),k hard ( x )=slice( x ). Equation 33
The slicer quantizes its argument x to the nearest constellation symbol according to some metric (e.g., Euclidean distance). A hard decision is applicable only to those symbols whose constellations are known to the receiver.
[0103] A mixed-decision map Ψ (s),k mixed (x) produces an output that is a soft decision or a hard decision, such as
Ψ ( s ) , k mixed ( x ) = { Ψ ( s ) , k hard ( x ) if SINR ( s ) , k > c ( s ) , k Ψ ( s ) , k soft ( x ) otherwise Equation 34
The mixed-decision map Ψ (s),k mixed (x) produces a hard decision if the SINR of a k th user of base station (s) exceeds a threshold c (s),k . Otherwise, a soft decision is performed. The SINR may be estimated with a time-averaged error-vector measurement (EVM). Time-averaging may cause a block of symbols to share the same SINR estimate.
[0104] An alternative mixed-decision map Ψ (s),k mixed (x) may act on individual symbols,
Ψ ( s ) , k mixed ( x ) = { Ψ ( s ) , k hard ( x ) if x ∈ C ( s ) , k ( slice ( x ) ) Ψ ( s ) , k soft ( x ) otherwise , Equation 35
where the constellation space for the symbol of a k th user of base station (s) is partitioned into hard- and soft-decision regions with C (s),k (b) denoting the hard-decision region for a symbol b from that user's constellation. If xεC (s),k (b), then a hard decision for x is made. One embodiment for defining C (s),k (b) is to include all points within a predetermined distance of b in the constellation space,
C (s),k ( b )={ x :distance( x,b )< c (s),k ( b )}, Equation 36
where any distance metric may be used (e.g., |x−b| p for some p>0) and the radii c (s),k (b) over the set of constellation points b are chosen such that the hard-decision regions are non-overlapping. Alternative embodiments of the invention may employ different partitions of the constellation space. For example, edge constellation points may be given unbounded hard-decision regions.
[0105] Both the average SINR and instantaneous approaches are applicable to any known constellation; they need not be restricted to BPSK, QPSK, or even QAM. Either of these mixed-decision approaches may be performed with the additional constraint that the receiver knows only the constellation employed for a subset of the active codes. Such situations may arise in EV-DO and HSDPA networks. In such cases, the receiver may use soft decisions for codes employing an unknown modulation. Those skilled in the art will understand that a modulation classification of these codes may be performed, which may be particularly useful in systems wherein all interfering codes share the same unknown constellation.
[0106] The following algorithm, which is illustrated in FIG. 13 , demonstrates one embodiment for performing IIC.
[0000] Algorithm 1:
[0107] Purpose: Estimate the
K = ∑ s = 0 B - 1 K ( s )
symbols in {circumflex over (b)} .
Notation: The iteration index is represented by a superscript [i]; i=−1 is the initialization; i=0 corresponds to the output of the front-end processor; and i>0 corresponds to the i-th ICU.
Definitions: b is in Equation 22
{circumflex over (b)} [i] is in Equation q is in Equation 17 R is in Equation 19 F is I or as in Equation 21 Γ [i] is in Equation 14 with elements defined in Equation 3-Equation 5 μ [i] is defined in Equation 23-Equation 27 Ψ maps each argument to a complex number to implement de-biasing as in Equation 28-Equation 30Equation and then symbol estimation as in Equation 32-Equation 36
Initializations: {circumflex over (b)} [−1] =0, a K×1 zero vector
Γ [−1] =I, a K×K identity matrix μ [−1] =1
Iterations: Index i=−1, 0, 1, . . . , M−1, where M is the number of times to iterate the succeeding update equation
Update Equation: {circumflex over (b)} [i+1] =Ψ{μ [i] ( q −RΓ [i] {circumflex over (b)} [i] )+FΓ [i] {circumflex over (b)} [i] }
Output: {circumflex over (b)} = {circumflex over (b)} [M] , the symbol estimates after M iterations of the update equation.
[0117] FIG. 13 shows an internal feedback loop comprising operations 1308 , 1301 , 1302 , 1306 , and an external feedback loop comprising operations 1308 , 1301 , 1303 , and 1304 . The output of the external feedback loop is q −RΓ [i] {circumflex over (b)} [i] , which is multiplicatively scaled 1305 by μ [i] . The scaled output is combined 1306 with the internal feedback loop to yield ( q −RΓ [i] {circumflex over (b)} [i] )+FΓ [i] {circumflex over (b)} [i] , which is processed by a symbol estimator 1307 and fed to the iteration delay 1308 that begins the internal and external loops.
[0118] Although embodiments of the invention are described with respect to forward-link channels, embodiments may be configured to operate in reverse-link channels. In the reverse link, different users' transmissions experience different multipath channels, which requires appropriate modifications to Rake processing and signal synthesis. For example, a front-end processor may incorporate one Rake for every user in every base station rather than a single Rake per base station. Similarly, a separate multipath channel emulator may be employed for imparting multipath delays and gains to each user's signal. Accordingly, the number of constituent finger signals will equal the sum over the number of multipath fingers per user per base station, rather than the sum over the number of multipath fingers per base station.
[0119] It is clear that this algorithm may be realized in hardware or software and there are several modifications that can be made to the order of operations and structural flow of the processing.
[0120] Those skilled in the art should recognize that method and apparatus embodiments described herein may be implemented in a variety of ways, including implementations in hardware, software, firmware, or various combinations thereof. Examples of such hardware may include Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), general-purpose processors, Digital Signal Processors (DSPs), and/or other circuitry. Software and/or firmware implementations of the invention may be implemented via any combination of programming languages, including Java, C, C++, Matlab™, Verilog, VHDL, and/or processor specific machine and assembly languages.
[0121] Computer programs (i.e., software and/or firmware) implementing the method of this invention may be distributed to users on a distribution medium such as a SIM card, a USB memory interface, or other computer-readable memory adapted for interfacing with a consumer wireless terminal. Similarly, computer programs may be distributed to users via wired or wireless network interfaces. From there, they will often be copied to a hard disk or a similar intermediate storage medium. When the programs are to be run, they may be loaded either from their distribution medium or their intermediate storage medium into the execution memory of a wireless terminal, configuring an onboard digital computer system (e.g., a microprocessor) to act in accordance with the method of this invention. All these operations are well known to those skilled in the art of computer systems.
[0122] The functions of the various elements shown in the drawings, including functional blocks labeled as “modules” may be provided through the use of dedicated hardware, as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be performed by a single dedicated processor, by a shared processor, or by a plurality of individual processors, some of which may be shared. Moreover, explicit use of the term “processor” or “module” should not be construed to refer exclusively to hardware capable of executing software, and may implicitly include, without limitation, digital signal processor DSP hardware, read-only memory (ROM) for storing software, random access memory (RAM), and non-volatile storage. Other hardware, conventional and/or custom, may also be included. Similarly, the function of any component or device described herein may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the implementer as more specifically understood from the context.
[0123] The method and system embodiments described herein merely illustrate particular embodiments of the invention. It should be appreciated that those skilled in the art will be able to devise various arrangements, which, although not explicitly described or shown herein, embody the principles of the invention and are included within its spirit and scope. Furthermore, all examples and conditional language recited herein are intended to be only for pedagogical purposes to aid the reader in understanding the principles of the invention. This disclosure and its associated references are to be construed as applying without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. | A receiver is configured for canceling intra-cell and inter-cell interference in coded, multiple-access, spread-spectrum transmissions that propagate through frequency-selective communication channels. The receiver employs iterative symbol-estimate weighting, subtractive cancellation with a stabilizing step-size, and mixed-decision symbol estimates. Receiver embodiments may be implemented explicitly in software or programmed hardware, or implicitly in standard Rake-based hardware either within the Rake (i.e., at the finger level) or outside the Rake (i.e., at the user or subchannel symbol level). | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application relates to and claims priority of U.S. provisional patent application (“Copending Provisional Application”), Ser. No. 61/810,661, entitled “Dynamic Switching Frequency Adjustment for Fast Transient Response,” filed on Apr. 10, 2013. The disclosure of the Copending Provisional Application is hereby incorporated by reference in its entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a control loop in a power converter. In particular, the present invention relates to dynamically adjusting the switching frequency in a control loop of a power converter to provide a fast response to output transients.
2. Discussion of the Related Art
In a power converter, the output capacitor is a key factor in achieving a high power density. There are two main design considerations for an output capacitor: (a) steady state voltage ripple and (b) voltage spike during a transient. In a conventional power converter, the total output capacitance is mainly designed for transient response. Good transient response is normally achieved by optimizing the bandwidth of the power converter's control loop. However, due to non-linearity, a higher bandwidth does not always result in a better transient response. This can be illustrated, for example, by a peak current mode-controlled power converter.
FIG. 1( a ) is a schematic diagram showing single-phase circuit configuration 100 for one type of power converter. As shown in FIG. 1( a ) , circuit configuration 100 includes a control module 101 receiving an input voltage V in and providing clock signals 102 a and 102 b , which drive switch 103 (“top-side switch”) and switch 104 (“bottom-side switch”), respectively. The operations of top-side switch 103 and bottom-side switch 104 transfer energy to output capacitor 106 through output inductor 105 . Based on feedback signal (V FB ), control module 101 operates to maintain output voltage V O at a steady state value. In some power converters, multiple sets of inductors and top-side and bottom-side switches may be used in a “multi-phase” configuration to drive a common output voltage.
FIG. 1( b ) shows the waveforms of output voltage (V O ), the output current (I O ), and the switching node signal (SW), in response to a step increase in load current of 15 A. In the power converter of FIG. 1( a ) , the design parameters are: (a) a 12-volt input voltage (V in ), (b) a 1-volt nominal output voltage (V O ), (c) a 400 kHz switching frequency (f SW ), (d) a 250 nH inductor (L), and (e) a 860 μF output capacitance (C OUT ), provided by two 330 μF/9 mΩ tantalum polymer capacitors, and two 100 μF/2 mΩ ceramic capacitors. The control loop bandwidth is around 60 kHz with 72° phase margin. As shown in FIG. 1( a ) , at time t=500 μs, the output load current increases by a 15 A step. Because the step current increase occurs immediately after the top-side switch is turned off, output voltage V O on the output capacitor drops rapidly to 0.92 volts until the top-side switch turns on again at the beginning of the next switching cycle (t=502.5 μs, about 2.3 μs later). During the switching cycle delay, the feedback control loop provides no help reducing the voltage drop at the output capacitor. The situation is more acute with small duty-cycle operation, as shown in FIG. 1 .
A non-linear control scheme may reduce the switching cycle delay. In the non-linear control loop a threshold voltage is selected. When the output voltage falls below the threshold voltage, a voltage undershoot condition is deemed occurred. When the voltage undershoot condition is detected, the top-side switch is immediately turned on, rather than waiting for the beginning of the next switching cycle. There are, however, two drawbacks in this method. First, the monitored threshold voltage is sensitive to both component values and the layout. Second, the nonlinear control scheme may interact with one or more other control loops (e.g., a linear control loop) to create undesired oscillations. These drawbacks introduce unreliability in conventional designs.
SUMMARY
According to one embodiment of the present invention, a method and a circuit dynamically adjust the frequency of a clock signal that drives the operations of a power converter. The method includes (a) detecting a change from a predetermined steady state value in an output voltage of the power converter; and (b) upon detecting the change, changing the frequency of the clock signal so as to restore the output voltage to the predetermined steady state value. The change, such as a load step-up, may be detected by comparing a feedback signal generated from the output voltage and a predetermined threshold voltage. In one implementation, changing the switching frequency is achieved by increasing (e.g., doubling) the frequency of the clock signal, as needed. According to one embodiment of the present invention, the frequency of the clock signal need only be changed for a predetermined time period.
The present invention is better understood upon consideration of the detailed description below in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1( a ) is a schematic diagram showing single-phase circuit configuration 100 for one type of power converter.
FIG. 1( b ) shows the waveforms of output voltage (V O ), the output current (I O ), and the switching signal that controls the top-side switch of a power converter, in response to a step increase of 15 A load current.
FIG. 2 illustrates a dynamic frequency adjustment scheme for improving transient response, according to one embodiment of the present invention.
FIGS. 3( a ) and 3( b ) show the performances of a conventional system and the same system adapted for using a dynamic switching frequency adjustment scheme of the present invention, respectively.
FIGS. 4( a ) and 4( b ) show the performances of a conventional system during a 10 A load current step-up and a 10 A load current step-down, respectively.
FIGS. 5( a ) and 5( b ) show the operations of a system using a dynamic switching frequency adjustment scheme of the present invention that substantially meets the design specifications of the conventional system of FIGS. 4( a ) and 4( b ) under a 0 A-to-10 A step-up and under 10 A-to-0 A step-down in load current, respectively.
FIG. 6 shows the voltage spike reductions for various threshold values, in accordance with one embodiment of the present invention.
FIG. 7( a ) shows clock circuit 700 which provides a clock signal for dynamically adjusting the switching frequency of a power converter for a load step-up, in accordance with one embodiment of the present invention.
FIG. 7( b ) shows selected signals of circuit 700 for implementing the dynamically adjusted switching frequency scheme.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to one embodiment of the present invention, a dynamic switching frequency adjustment scheme improves transient response. FIG. 2 illustrates this dynamic frequency adjustment scheme, according to one embodiment of the present invention. FIG. 2 shows output voltage V O , feedback signal V FB , and the switching clock signals of the present invention. Feedback signal V FB may be derived from and may be made proportional to output voltage V O . The methods of the present invention detect a transient change in output voltage V O , such as a voltage undershoot condition. The voltage undershoot condition occurs, for example, when output voltage V O falls below a threshold voltage, such as during a load “step-up” (i.e., a sharp rise in load current). In the example of FIG. 2 , feedback voltage V FB is 0.6V and the threshold voltage is set at 0.975 times V FB , or 585 mV. When the voltage undershoot condition is detected, a controller switches to a higher switching frequency, so as to reduce the switching cycle delay. In FIG. 2 , the frequency is doubled. As shown in FIG. 2 , at the higher switching frequency, the delay between detecting the voltage undershoot condition and the time the top-side switch is turned on (i.e., the switching cycle delay) is reduced from 2.31 μs to 1.05 μs. Consequently, the voltage undershoot is reduced from 86 mV ( FIG. 1 ) to 46 mv, which is approximately a 46% reduction. The higher frequency operation may be maintained for 10 to 20 original switching cycles to ensure output voltage V O recovers smoothly. Thus, the voltage spike experience during the transient condition is significantly reduced, or equivalently, a smaller output capacitance is required to meet the same transient spike window. The methods of the present invention are equally applicable in multi-phase power converters as in single-phase power converters.
FIGS. 3( a ) and 3( b ) show the performances of a conventional system and the same system adapted for using the dynamic switching frequency adjustment scheme of the present invention, respectively. The system of FIGS. 3( a ) and 3( b ) has the following design parameters: (a) a 12-volt input voltage (V in ), (b) a 1-volt nominal output voltage (V O ), (c) a 400 kHz switching frequency (f SW ), (d) a 330 nH inductor (L), and (e) a 860 μF output capacitance (C OUT ), provided by two 330 μF/9 mΩ tantalum polymer capacitors, and two 100 μF/2 mΩ ceramic capacitors. As shown in FIGS. 3( a ) and 3( b ) , the voltage undershoot is reduced from 133 mV to 89 mV by doubling the clock frequency for a load current step-up from 0 A to 20 A.
As discussed above, the methods of the present invention allow the same design specification to be achieved with a lesser output capacitance requirement. For example, FIGS. 4( a ) and 4( b ) show the performances of a conventional system during a 10 A load current step-up and a 10 A load current step-down, respectively. This conventional system uses peak current mode control. The design specification for that conventional system is: (a) a 12-volt input voltage (V in ), (b) a 1-volt nominal output voltage (V O ), (c) a 400 kHz switching frequency (f SW ), and (d) a 40 mV peak-to-peak voltage (V pp ) limit for 10 A step-up and 10 A step-down in load currents. In the example of FIGS. 4( a ) and 4( b ) , these specifications are substantially satisfied by a 330 nH inductor (L), and a 2220 μF output capacitance (C OUT ), which was provided by four 330 μF/6 μmΩ tantalum polymer capacitors, and nine 100 μF/2 mΩ ceramic capacitors. As seen in FIGS. 4( a ) and 4( b ) , a 22.25 mV negative voltage spike is experienced during a 0 to 10 A step-up in load current, and a 19.5 mV during a 10 A to 0 A step-down in load current, thus providing a total peak-to-peak voltage spike of 41.75 mA.
The design specification of the conventional system of FIGS. 4( a ) and 4( b ) may be met using a dynamic switching frequency adjustment scheme of the present invention with a lesser requirement on the output capacitance. FIGS. 5( a ) and 5( b ) show the operations of such a system under a 0 A-to-10 A step-up and under 10 A-to-0 A step-down in load current, respectively. In the example of FIGS. 5( a ) and 5( b ) , the switching frequency is doubled, when a voltage undershoot condition (i.e., load current step up) is detected, and halved, when a voltage overshoot condition is detected (i.e., load current step-down) is detected. In FIGS. 5( a ) and 5( b ) , a 18.3 mV negative voltage spike is experienced during a 0 to 10 A step-up in load current, and a 23.75 mV during a 10 A to 0 A step-down in load current, thus providing a total peak-to-peak voltage spike of 42.05 mA. The specification is met by a 330 nH inductor (L), and a 1720 μF output capacitance (C OUT ), which was provided by four 330 μF/6 mΩ tantalum polymer capacitors, and four 100 μF/2 mΩ ceramic capacitors, which represents a reduction of output capacitance by 23%. Fewer ceramic capacitors also save significant cost. Further, as compared to the conventional nonlinear control method described above, a power converter using a dynamic switching frequency adjustment scheme of the present invention need only run in a linear control loop. Consequently, there is no concern related to interactions between a nonlinear control loop and a linear control loop, so that transient recovery can occur smoothly.
An additional advantage of a system using a method of the present invention is its relative insensitivity to threshold setting. FIG. 6 shows the voltage spike reductions for threshold values that are set from 0.99 times of reference voltage V ref to 0.95 times reference voltage V ref . Reference voltage V ref may be set to, for example, 0.6V. As shown in FIG. 6 , for a 10 A load current step-up, doubling the switching frequency provides the same performance improvement (i.e., a voltage spike reduction from 86 mV to 46 mV) over the range of threshold voltages between 0.96*V ref and 0.99*V ref .
FIG. 7( a ) shows clock circuit 700 which provides a clock signal for dynamically adjusting the switching frequency of a power converter for a load step-up, in accordance with one embodiment of the present invention. FIG. 7( b ) shows selected signals of circuit 700 for implementing the dynamically adjusted switching frequency scheme. As shown in FIG. 7( a ) , circuit 700 receives (i) feedback signal V FB , representative of output voltage V O , (ii) threshold voltage V threshold , and (iii) clock signals CLK 1 and CLK 2 of the same frequency, but separated in phase by a 180°. The waveforms of clock signals CLK 1 and CLK 2 are shown as waveform 751 and 752 in FIG. 7( b ) . When comparator 701 detects a load step-up condition, which occurs when V FB falls below threshold voltage V threshold , its output signal triggers one-shot timer 702 to provide a pulse in enable signal 703 . The pulse in enable signal 703 has a duration spanning about 10 cycles of clock signal CLK 1 . Enable signal 703 is shown as waveform 753 in FIG. 7( b ) . Enable signal 703 causes clock signal CLK 2 to be merged by AND gate 704 and OR gate 705 with clock signal CLK 1 to provide output clock signal CLKx. The waveform of output clock signal CLKx is shown as waveform 754 in FIG. 7( b ) . As shown in FIG. 7( b ) , in waveform 754 , the frequency of output clock signal CLKx is doubled during the duration of the pulse in enable signal 703 .
The above detailed description is provided above to illustrate specific embodiments of the present invention and is not intended to be limiting. Numerous modifications and variations within the scope of the present invention are possible. The present invention is set forth in the accompanying claims. | A method and a circuit dynamically adjust a frequency of a clock signal that drives the operations of a power converter. The method includes (a) detecting a change from a predetermined value in an output voltage of the power converter; and (b) upon detecting the change, changing the frequency of the clock signal so as to restore the output voltage. The change, such as a load step-up, may be detected by comparing a feedback signal generated from the output voltage and a predetermined threshold voltage. In one implementation, changing the switching frequency is achieved in increasing (e.g., doubling) the frequency of the clock signal, as needed. The frequency of the clock signal need only be changed for a predetermined time period. | 7 |
This application is a continuation of application Ser. No. 07/237,641 filed Aug. 26, 1988, now U.S. Pat. No. 4,878,069, which is a continuation of application Ser. No. 07/082,946, filed Aug. 10, 1987, now abandoned, which is a continuation of application Ser. No. 06/752,538, filed July 8, 1985, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an ink jet recording apparatus and more particularly to an improvement of an ink jet recording apparatus of the type in which one or more of a plurality of ink containers are replaceably fitted into a carriage.
2. Description of the Prior Art
As is well known, ink jet recording apparatuses have characterizing features wherein printing is effected with the generation of a noise level which is kept lower than that of wire dot type or heat sensitive type recording apparatus. An ink jet apparatus may be suitably employed for printing at a high speed. Moreover, color printing is easy to be achieved. For the above reasons, it is preferably used for an output device of electronic apparatus in the form of a printer, facsimile apparatus or the like.
The ink jet recording apparatus is generally constructed such that ink held in the ink containers is introduced into the recording head and it is then injected from ink discharging orifices toward a recording medium (e.g. paper) by activating an ink discharging energy generator disposed on the recording head in response to a printing pattern signal (recording signal). The ink discharging energy generator is adapted to generate energy required for discharging liquid (ink) from the ink discharging orifices. Thus, dot printing is effected by repeatedly injecting ink toward the recording medium.
To avoid connection of ink containers to the recording head by using long feeding tubes a recording apparatus of the above-mentioned type is often so constructed that ink containers are replaceably mounted on a carriage adapted to move along the recording medium together with a recording head disposed on the carriage. As a result, the recording apparatus can be designed in smaller dimensions.
In a conventional ink jet recording apparatus, a substantially rectangular cartridge type ink container is mounted on the carriage by inserting it from above or from the back side relative to the carriage.
On the other hand, the carriage is provided with electric circuits for turning on the recording head to activate the energy generator and a guide section for displaceably supporting the carriage. To allow the electric circuits and the guide section to be accomodated in a limited space on the carriage a variety of proposals have been already made from the design viewpoint.
However, since the conventional recording apparatus is so constructed that each of the ink containers is replaceably mounted horizontally in the above-described manner, it is difficult to keep the space required for accomodating therein electric circuits and making electric connection therebetween when the recording apparatus is designed in smaller dimensions. Another problem of the conventional recording apparatus is that there is a necessity for forming projections in order to build the guide section which serves to displaceably support the carriage, resulting in the design of the recording apparatus in a compact structure being achieved only with much difficulty.
Yet, another problem with the conventional recording apparatus is that ink held in each of the ink containers cannot be fully consumed in spite of the fact that an ink intake port is located at the position in the proximity of the bottom of the ink container, because the bottom of the ink container is flat and moreover it is held horizontally.
SUMMARY OF THE INVENTION
Hence, the present invention has been made with the foregoing problems in mind.
It is an object of the present invention to provide an improved ink jet recording apparatus of the previously mentioned type which assures that a space in the carriage is utilized in the optimum manner by forming two hollow spaces at both the upper and lower parts of the carriage to accomodate electric circuits in the one hollow space and to build a guide section in the other hollow space.
It is another object of the present invention to provide an improved ink jet recording apparatus of the previously mentioned type which assures that ink stored in each of the ink containers is fully used.
It is another object of the present invention to provide an improved ink jet recording apparatus which is constructed within compact structure and in which each of the ink containers can be easily fitted into the carriage.
It is a further object of the present invention to provide an improved ink jet recording apparatus of the previously mentioned type which assures that each of the ink containers is replaceably fitted into the carriage in such an inclined state that the rear side is raised above the fore side thereof.
To accomplish the above objects there is proposed, according to the present invention, an ink jet recording apparatus of the type in which a recording head is carried on a carriage adapted to move along a recording medium and ink stored in a plurality of ink containers is introduced into the recording head so that ink is injected through a plurality of ink discharging orifices toward the recording medium by activating an energy generator disposed on the recording head in response to a recording signal, the energy generator serving to generate energy which is utilized for the purpose of discharging ink, wherein the improvement consists in that the ink containers are replaceably fitted into the carriage in such an inclined state that the rear side is raised above the fore side thereof.
When the ink containers are fitted into the carriage, two hollow spaces are formed at both the upper and lower parts of the carriage. One of them is utilized to accommodate electric circuits and the other one is utilized to house a guide section for displaceably supporting the carriage. Thus, the space of the carriage can be utilized in the optimum manner.
Since each of the ink containers is fitted in the inclined posture, ink stored therein can be fully consumed.
By virtue of arrangement of the recording apparatus made in that way it can be designed and constructed in smaller dimensions with useles space being reduced substantially.
Other objects, features and advantages of the present invention will become more clearly apparent from reading of the following description which has been prepared in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings will be briefly described below.
FIG. 1 is a vertical sectional view of an ink jet recording apparatus in accordance with an embodiment of the invention, and
FIG. 2 is a front view of the apparatus as seen from line II--II in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Now, the present invention will be described in greater detail hereunder with reference to the accompanying drawings which illustrate a preferred embodiment thereof.
FIG. 1 is a vertical sectional view of a carriage on which a plurality of ink containers are mounted. A recording head 4 and a plurality of ink containers 5 are mounted on the carriage 3 adapted to move along a recording material (paper) 2 which is brought in contact with a platen 1. In the illustrated embodiment, as can be seen in FIG. 2, the apparatus is shown to include the number (four) of recording heads 4 to effect color printing and the same number (four) of ink containers 5 as that of the recording heads 4.
As is apparent from the drawing, each of the ink containers 5 in each of container fitting or supporting sections 6 is supported fitting sections 6 in such an inclined state that it is turned by a certain angle in the clockwise direction as seen in the drawing. The container fitting section 6 is designed in the cavity-shaped configuration of which the left-hand side is raised up above the right-hand side as seen in the drawing.
The container fitting section 6 has a hollow needle 8 fixedly secured thereto through an opening in the fitting section 6, by way of which needle the container is in communication with the recording head 4. As will be readily understood from the drawing, an ink intake hole 9 is formed by piercing the hollow needle 8 through an intake portion on the container 5 in connection with of fitting operation of the container.
In the illustrated embodiment the container 5 has a folding portion at the position located in the fore part of an upper projection 10 and an air vent hole 10A is formed by breaking the folding portion under the effect of a thrusting force provided by a thrusting portion on the foremost end of a communication tube 11 which is fitted through the wall of the carriage 3. It should be noted that breaking of the folding portion is achieved in connection with the of fitting operation of the container. The air vent hole 10 communicates with the outside atmosphere via the communication tube 11.
Since the ink container 5 is fitted in such an inclined posture that it is turned by a predetermined angle of θ in the clockwise direction as seen in the drawing, hollow spaces having the substantially triangular sectional configuration are formed at the upper fore part of the carriage as well as at the lower rear part of the same. In the illustrated embodiment the hollow space located at the upper fore part of the carriage 3 serves to accomodate therein a circuit base board 12 with an electric circuit for turning on the recording head 4 arranged thereon and other electronic components such as flexible circuits 13 or the like. On the other hand, the hollow space located at the lower rear part of the carriage 3 serves to build a guide portion 14 for displaceably supporting the carriage 3.
Thus, the carriage 3 is ready to move in the leftward or rightward direction (in the vertical direction as seen relative to the plane of the drawing) with the aid of a guide shaft 15 extending through the guide portion 14 and another guide shaft 17 extending through the fore guide portion 16. Ink 18 held in the ink container 5 is introduced into the recording head 4 via the hollow needle 8 and the ink feeding tube 7. In response to printing pattern signals transmitted from the electric circuits 12 and 13 a plurality of discharging orifices on the recording head 4 (identified by a plurality of recording head chips 19 in the drawing which constitute the discharging orifices each of which is in operative association with an energy generator) become activated whereby ink is injected toward the recording material 2 to effect ink dot printing.
As is apparent from FIG. 1, the apparatus is provided with a waste ink reservoir 20 in the bottom area of the carriage 3 and an ink absorbing material 21 is placed in the waste ink reservoir 20. The latter is communicated with the air vent hole 10A via the communication tube 11 and the passage 22 which in turn is communicated with the lower part of the recording head chips 19 via a passage 23 disposed below the recording head 4. Thus, ink leaked from the air vent hole 10A and waste ink leaking from the discharging orifices or dripping from the recording head chips 19 is introduced into the waste ink reservoir 20 and it is then absorbed in the ink absorbing material 21.
As described above, the apparatus of the invention is so constructed that a plurality of ink containers 5 are fitted into the carriage 3 in the inclined posture and hollow spaces having the substantially triangular sectional configuration are formed at both the upper and lower parts of the carriage 3 so that electric circuits 12 and 13 for turning on the recording head 4 are accomodated in the upper hollow space and a guide portion 14 is accommodated for the purpose of supporting the carriage 3, in the lower hollow space. As a result, the apparatus has an advantageous feature that a limited space in the carriage 3 can be utilized in the optimum manner.
Further, since the ink intake hole 9 is located at the position in the proximity of the lowermost part of the bottom of the ink containers 5 which are fitted into the carriage 3 in the inclined posture, ink stored in the containers can be fully taken out therefrom without any loss.
In the illustrated embodiment four ink containers are mounted on the carriage but the present invention should not be limited only to this. Alternatively, the present invention may be applied to the case where a single container is mounted for a monochromatic printer or the case where more than four ink containers are mounted on the carriage in the above-described manner.
It should , of course, be understood that the present invention should not be limited only to the foregoing embodiments but various changes or modifications may be made in any acceptable manner without departing from the spirit and scope of the invention as defined by the appended claims.
Incidentally, no description has been made above with respect to the energy generator but any well known means, for instance, a converter adapted to convert electric energy into thermal energy (heating element or the like) in the case where thermal energy is utilized and a converter adapted to convert electric energy to mechanical energy (piezo-electric element, magnetostriction element or the like) in the case where mechanical energy is utilized may be employed for the appartus, provided that liquid (ink) can be injected from ink discharging orifices in response to recorded information with the aid of the energy generator. | An ink jet recording apparatus has a recording head and replaceable ink container. The ink container is removably mounted on the apparatus and a hollow needle, connected by an ink supply path to a recording head, punctures the ink container as it is put in place on the apparatus. An absorbing material is located on the apparatus near the needle to absorb any waste ink than may fall from the needle or the ink container as the ink container is put in place or removed from the apparatus. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Pursuant to USC 35 §119(e) 3 the present application claims the benefit of a Provisional Application of Ser. No. 60/001,336 filed Nov. 1, 2007 by the present inventor, which is incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to a mechanical broadhead. More specifically the present invention relates to a family of arcuately expandable mechanical broadheads.
BACKGROUND OF THE PRIOR ART
[0003] Bow hunting is one of mans' oldest arts and has benefited over time from technological improvements towards the fundamental equipment namely the bow and the arrow including various parts and materials relative thereto. Regarding the arrow, stone points have replaced bare wood. Metal points and metal broad heads replaced the stone points. Countless alterations have been made toward these and other fundamentals relative to this ancient, crowded art.
[0004] One such improvement toward the typical metal broadhead is the so called, mechanical broadhead. These devices are found to possess a retracted state and a deployed state. During portage, loading, launch and flight, mechanical broadheads while in the retracted state will provide a minimal drag profile along the outermost longitudinal surface. Though, upon surface penetration of a target mass these type devices' blades expand outward and provide greater cutting during penetration of the flesh of the game animal. The stated goal amongst a great many bow hunters is toward a mechanical broad that performs in flight as well as a field point. “Field points” describes an arrow used in practice as well as in competition and feature a bare, tapered point in which nothing extends outward of the lateral surface of the arrow shaft. Drag and deflection are held to a minimum with field points.
[0005] U.S. Pat. No. 6,830,523 issued to Kuhn is substantially exemplary an “unfolding” type broadhead, in which the blades are hinged from a retracted state to an unfolded, deployed state. Well known in this crowded art, these type devices require heavy steel blades as a result of the impact received on impact and further, in that the trailing edge is not physically secured to the shaft of the broadhead nor that of the arrow shaft. Therefore the hinge, point of attachment and the blades themselves must be constructed so as to survive these very significant impact forces.
[0006] The second type mechanical broadhead is the so called “sliding” type mechanical broadhead. U.S. Pat. No. 6,935,976 issued to Grace Jr. et al is exemplary relative to this type arrowhead. These type sliding broadheads are those in which the blades slide, upon impact, and ramp outward to a deployed state. These devices also suffer from the fact that careful attention much be given to the weight and strength of these type blades whereby upon impact they do not break or disintegrate upon impact. These type considerations, and responses thereto, invariably increase the weight of these type arrowheads. Further, while being deployed upon impact, the mass of these type blades cause the arrow to lose valuable speed thereby lessening the effect thereof.
[0007] Another drawback relative to the above prior art broadheads is that impact upon bone can seriously hinder in not prevent further penetration of the target animal, in that these type broadhead are extremely rigid and would not contour along the terminal ballistic path if encountering bone, even as a glancing blow. These type broadheads' blades would tend to “dig in” and be stopped by a significant, bony obstacle, which could result in a wounded, but not incapacitated animal.
SUMMARY
[0008] The present invention relates to a family of mechanical broadheads in which retractable blades may be arcuately expanded from a wound to an unfurled, deployed position. The blades of the present invention may be coiled around a ferrule body and uncoiled upon impact. The blades may be restrained by a sliding outer body, bales, or by having been locked and cocked into place while under the tension of a coil spring and being extended though stationary slots. Blades of the present invention could be constructed of very thin sheet type metal, and much like a paper cut, would be able to slice through flesh with very little resistance due in part to the very thin profile of the cutting surface and body. Prior art mechanical blades are not capable of being constructed of paper thin metals for obvious reasons.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 shows a perspective view of the sliding outer body embodiment of the present invention while in the retracted state.
[0010] FIG. 2 shows a perspective view of the sliding outer body embodiment of the present invention while in the deployed state.
[0011] FIG. 3 shows a perspective view of a first alternate embodiment
[0012] FIG. 4 shows a perspective view of the first alternate embodiment with the outer body in the deployed position with no blades present.
[0013] FIG. 5 shows a perspective view of a second alternate embodiment in a cocked state.
[0014] FIG. 6 shows a perspective view of the second alternate embodiment in the deployed or triggered state.
[0015] FIG. 7 shows a side elevation of the blade ferule and point absent the cover of the second alternate embodiment.
[0016] FIG. 8 shows the attachment point for the fixed axle of the second alternate embodiment.
[0017] FIG. 9 shows the spring and winding chamber of the second alternate embodiment.
[0018] FIG. 10 shows the stop bar assembly of the second alternate embodiment.
[0019] FIG. 11 shows a bale secured arcuately expandable third alternate embodiment in a retracted state.
[0020] FIG. 12 shows a bale secured arcuately expandable third alternate embodiment in a deployed state.
[0021] FIG. 13 shows a bale secured arcuately expandable third alternate embodiment in a retracted state.
[0022] FIG. 14 shows a bale secured arcuately expandable third alternate embodiment in a deployed state.
DESCRIPTION OF THE INVENTION
A First Embodiment of the Invention
[0023] Referring to FIG. 1 , a first embodiment a sliding outer body broadhead 10 of the present invention is shown and includes a sliding outer body 12 . Disposed along the outer surface of the sliding outer body 12 are fixed blades 14 . These blades along with being capable of slicing into a target mass will urge the outer body in a direction opposite to that of the flight of the arrow. A plurality of weight relief holes 18 are disposed along the body of the sliding outer body 12 . A locking clip 26 is shown attached to a point 28 . The point 28 is disposed on the leading distal end of the sliding outer body broadhead 10 . Still referring to FIG. 1 a stop ring 32 is disposed on the broadhead rearward of the sliding outer body 12 and provides a stop relative to the sliding outer body's travel.
[0024] Referring to FIG. 2 , the first embodiment 10 is shown in a deployed state in which a plurality of flexible blades 20 are extended outward of a ferrule body 22 . The ferrule body 22 is pivotably disposed relative to the shaft of the broadhead. The blades 20 are secured to the ferrule body by corresponding set screws 24 . The blades would preferably be constructed of a thin metal not dissimilar in thickness to that of the steel tape found in tape measures, though could be constructed of much thinner material.
[0025] Still referring to FIG. 2 , upon impact the sliding outer body 12 would be urged backward releasing the blades 20 which, in the retracted state, are secured tightly around the grooves of the ferrule body 30 sufficient to be contained by the sliding outer body. The blades would preferably be constructed of flat stock whereby the natural state of this material would be flat and linear and would resist being coiled and once coiled would flatten if not restrained. In order to return to a retracted state, a blade guide 16 is disposed along the leading edge of the outer body 12 , in which a single blade may be aligned and wound by rotating the blade point 28 . This process would continue until all blades were wound and covered.
[0026] It may be preferable that the sliding outer body 12 be rotatable relative to the device and that the ferrule body be fixed and non rotatable. In the later case, retracting the blades would be effected by sliding the outer cover forward engaging the rearmost blade then winding the cover until the secure blade disappears under the sliding blade cover. This operation would be continued until each blade is retracted. The sliding cover would then be secured by the clip 26 and recess latch.
[0027] Referring to FIG. 3 , a first alternate embodiment is shown using a more sweeping type fixed blades in which two retractable blades would be contained in an arrangement similar to that of the first embodiment. FIG. 3 shows the sliding outer cover in the retracted state. FIG. 4 shows the sliding outer cover in the deployed state.
[0028] Referring to FIG. 5 a second alternative embodiment, a spring loaded cockable broadhead 34 is shown. The blades 20 as with the previous embodiment are constructed of thin, flexible sheet type steel. In this figure the blades are in a retracted cocked state, wherein the point 28 is shown in an cocked position being extended slightly forward relative to the broadhead.
[0029] Referring to FIG. 6 , the spring powered cockable broadhead is shown in a deployed state while piercing into a target mass 29 . The point 28 is shown depressed after meeting sufficient resistance from the target mass 29 upon or just prior to penetration, whereupon the blades 20 are projected outward from a plurality of slots 36 found in a blade retention cover 41 . Blade slots 36 allow for the blades 20 to extend outwardly in a substantially transverse plane to that of the broadhead 34 . A screw connector 40 is shown, as typical with broadheads in general, provides a means for connecting the broadhead to the shaft of the arrow.
[0030] Referring to FIG. 7 , a view of the cockable broadhead is shown in which the blades and the retention cover are not included. The fixed axle 42 is shown and a spring/trigger housing 66 is shown just to the rear of the point 28 .
[0031] Referring to FIG. 8 an enlarged view of the axle 42 is shown along with a set screw 67 whereby the axle 42 may be secured to the shaft of the broadhead in a non rotatable state.
[0032] Referring to FIG. 9 The spring/trigger mechanism is shown in a wound and cocked position. The point 28 is shown extended outwardly in a windable/cocked position. The point 28 is fixedly disposed on a winding shaft 38 which in turn is rotatably disposed on the fixed axle 42 . Fixedly disposed on the winding shaft 38 is a ratchet assembly 54 comprising a ratchet gear 46 and a stop bar assembly 59 . The ratchet gear 46 is held to a clockwise/only moveable state by means of a stop bar 56 and a stop bar spring 65 . The point 28 is able to crank in a clockwise motion in which to wind a spring 45 . The spring 45 is held fixed to the rotatable hub with tab 44 and though not shown the spring 45 would be anchored to the fixed axle 42 . A winding assembly 48 comprises a generally bracket shaped assembly which meshes into the winding gear 52 . When the point 28 is extended outward, as with winding a watch, the winding assembly will mesh with the winding gear 52 with which to enable the tightening of the spring 47 causing the blades to retract into a cocked state.
[0033] FIG. 10 shows an enlarged view of the stop bar assembly 59 in which a spring 60 secures a ratchet member 56 in a stable downward position relative to the stop bar 58 . The ratchet member 56 is hingeably disposed on a shaft 64 extending outward from a stop bar anchor 62 .
[0034] Referring to FIG. 11 a third alternate embodiment: a bale secured broadhead 69 of the present invention is shown. This embodiment is comprised of a plurality of blades 20 capable of being held arcuately wrapped to the shaft of the broadhead by means of a pair of bales 70 . The bales are pivotably disposed rear of the blades and when securing the blades 20 would be clipped by means of respective clips 72 disposed forward of the blades 20 . Though not shown the blades 20 are disposed as with previous type embodiment on the ferule body by means of set screws or other suitable fasteners. Still referring to FIG. 11 , the blades 20 are shown in a retracted state. Though not shown, the ferule body of the bale secured broadhead would be pivotable disposed along a fixed axle ridgidly disposed within the screw base allowing for free revolution therealong. A hinge collar 76 and a clip collar 78 would be fixedly disposed along the fixed axle.
[0035] FIG. 12 shows a perspective view of the bale secured blades in a deployed state.
[0036] FIG. 13 shows the bale secured broadhead in a retracted state.
[0037] Operation of the third alternate embodiment.
[0038] In order to retract the blades 20 with the bale secured broadhead 69 the user would clip the bales in place and wind the point until the blades 20 are tightly wound along the shaft of the broadhead where the blades are respectively attached thereto.
[0039] It should be noted that within the bow hunting/broadhead art these devices are typically screwable or otherwise affixable to the shaft of an arrow. The simplicity of the present invention's blade(s) would allow for the attachment of same to what is commonly known as a field point. In fact a channel could be recessed within the shaft of an aluminum or carbon fiber shaft for the expressed purpose of attaching these type blades directly onto the shaft further reducing the cost of production thereby.
[0040] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example, and not limitation. It will be apparent to persons skilled in the relevant art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention. This is especially true in light of technology and terms within the relevant art(s) that may be later developed. Thus, the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. | The present invention relates to a family of arcuately expandable mechanical broadheads, wherein at least one thin metal strip may be curled around and restrained to the shaft of a broadhead that once released may unfurl into a cutting surface thereby enhancing, and adding to, the wound surface of a target mass. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS AND CLAIM FOR FOREIGN PRIORITY
This application is a continuation of U.S. patent application Ser. No. 09/624,473 (now abandoned), filed Jul. 24, 2000 as a divisional of U.S. patent application Ser. No. 08/913,144 (now U.S. Pat. No. 6,126,920), filed Jan. 12, 1998 as a §371 United States National Phase filing of PCT/GB96/00490 (expired), filed Mar. 1, 1996 claiming priority from GB 9504265.1, filed Mar. 3, 1995. The entire contents of each of the earlier applications is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to an improved pharmaceutical composition for the topical administration of corticosteroid-active substances to the skin of a subject.
BACKGROUND OF THE INVENTION
Corticosteroids, particularly in the form of ester compounds, are used, inter alia, in the treatment of skin diseases in humans, such as, for example, eczema, infantile eczema, atopic dermatitis, dermatitis herpetiformis, contact dermatitis, seborrheic dermatitis, neurodermatitis, psoriasis and intertrigo. Formulations containing such active substances have conventionally been applied to the skin site in the form of alcoholic solution, lotions or creams. However, there is a high degree of ineffectiveness with such formulations. Lotions and creams are generally too viscous o allow efficient penetration of the active ingredient to the epidermis, and solution have a tendency to evaporate before penetrating the epidermis. In addition, convention cream bases are irritating to the ski, particularly over the often long exposure that is required, and the fluidity of lotions often makes the physical application difficult to control. Moreover, it is necessary to rub such formulations into the target site to improve the penetration of the active substance into the epidermis, an action which itself produces irritation.
There has therefore been a very real need in the treatment of skin disorders requiring treatment with corticosteroids for improved formulations which target the most effective corticosteroid to the skin site with improved delivery of the active substance, with decreased inconvenience and irritation, and increased ease of use for the patient.
SUMMARY OF THE INVENTION
The present invention provides an improved composition which addresses these needs.
In one embodiment, the present invention provides a foamable pharmaceutical composition comprising a corticosteroid active substance, a quick-break foaming agent, a propellant and a buffering agent.
Such a composition is applied to the skin site (after foaming) as a foam which is a thermophobic (heat sensitive) quick-break foam. On application to the skin, the composition is initially in the form of a mousse-like foam. The quick-break foam slowly breaks down at the skin temperature to a liquid to allow the alcohol and active substance to saturate the treatment site. Such a system provides enhanced penetration of the alcohol and active substance through the epidermis. Because the composition is supplied as a mousse, the semi-rigid behavior of the composite makes it easier to handle and physically control. The foamed composition, when applied, provides a thick ball of foam which disintegrates easily when spread, allowing proper coverage of the skin site to be treated without premature evaporation of the solvent. It has been found important to include a buffering agent in the composition to stabilize the active isomer of the corticosteroid active substance in the complex foamable composition, otherwise the complex interactions within the foamable composition may result in the instability of the more active isomer.
DETAILED DESCRIPTION OF THE INVENTION
Use of a quick-break foaming agent is required in the present invention. Such agents are known. Suitable quick-break foaming agents in the present invention are those described in Australian Patent Number 463216 and Published International Patent Application WO 85/01876. It is generally preferred that the quick-breaking foaming agent comprises an aliphatic alcohol, water, a fatty alcohol and a surface active agent. Particularly preferred is a quick-break foaming agent having the following composition:
(a) an aliphatic alcohol, preferably in amounts of 40–90% w/w composition, more preferably, 55–70% w/w, and especially preferred, 57–59% w/w; (b) water, preferably in amounts of 10–40% w/w; (c) at least one fatty alcohol, preferably in amounts of 0.5–10% w/w; and (d) a surface active agent, preferably an ethoxylated sorbitan ester (as emulsified), typically in amounts of 0.1–15% w/w.
In the quick-break foaming agent, the fatty alcohol may be chosen from, for example, cetyl, stearyl, lauryl, myristyl and palmityl alcohols and mixtures of two or more thereof. Mixtures of cetyl alcohol and a stearyl alcohol such as octadecan-1-o1 have been found to be particularly preferred; the ratio between these two components may be adjusted to maintain foam viscosity throughout the broadest possible temperature range. In this situation, the stearyl alcohol maintains the viscosity at temperatures above 20° C. whilst cetyl alcohol maintains the viscosity below 20° C.
The aliphatic alcohol may preferably be chosen from methyl, ethyl, isopropyl and butyl alcohols, and mixtures of two or more thereof. Ethanol has been found to be particularly preferred.
Surface active agents utilized in the quick-break foaming agent may preferably be chosen from ethoxylated sorbitan stearate, palmitate, oleate, nonyl phenol ethoxylates and fatty alcohol ethoxylates, and mixtures of two or more thereof. Thus, for example, Polysorbate 60 (a mixture of partial stearic esters of sorbitol and its anhydrides copolymerized with approximately 20 moles of ethylene oxide for each mole of sorbitol and its anhydrides) has been found to be particularly preferred. The surface active agent enhances the fatty alcohol solubility in the system and enhances foam formation.
The propellant used may be chosen from conventional aerosol propellants. Thus, one may select the propellant from propane, butane, dichloro difluoro methane, dichloro tetrafluoro ethane, octafluoro cyclobutane, and mixture s of two or more thereof. It is necessary to select a propellant most compatible with the entire system. It is particularly preferred that the propellant be present in amounts preferably of 3–30% w/w, more preferably, 3–10% w/w, and most preferably, 3–5% w/w. The maximum level of propellant will be determined as the amount miscible with the utilized water/aliphatic alcohol ratio. In addition to acting as a propellant, the propellant will also act as a solvent for the fatty acids and active substances in the aqueous/alcoholic system.
It is possible that other additives may be used. Thus, it is preferred to add a humectant to reduce the drying effects of the aqueous aliphatic alcohol. Such a humectant may preferably be present in an amount of 0.1–10% w/w and more preferably 0.5–3.0% w/w. To is particularly preferred that the humectant be propylene glycol, but other humectants such as glycerine, panthenol and sorbitol may also be use.
The composition of the present invention may be used to deliver corticosteroid compounds which have utility in the topical treatment of skin disorders. Thus, for example, the composition of the present invention may be used to deliver the following topically-effective corticosteroid:
alclometasone dipropionate
fluclorolone acetonide
amcinonide
fluocinolone acetonide
beclomethasone dipropionate
fluocinonide
betamethasone benzoate
fluocoritin butyl
betamethasone dipropionate
fluocortolone preparations
betamethasone valerate
fluprednidene acetate
budesonide
flurandrenolone
clobetasol propionate
halcinonide
clobetasol butyrate
hydrocortisone
desonide
hydrocortisone butyrate
desoxymethasone
methylprednisolone acetate
diflucortolone valerate
mometasone furoate
flumethasone pivalate
triamcinolone acetonide
and pharmacologically effective mixtures thereof
Compositions according to the invention are especially advantageous for the topical administration to the skin of human subjects of betamethasone and its derivatives, such as betamethasone benzoate, betamethasone dipropionate and betamethasone valerate. It is particularly preferred to use the valerate ester, especially in the treatment of psoriasis.
The corticosteroid active substance is preferably present in an amount o 0.01–1.0% w/w and more preferably, 0.05–0.2% w/w.
In view of the complexity of the composition, it has been found that unexpectedly, in order to ensure stability of the active isomer of the corticosteroid in the composition, and thus to ensure delivery of the most active isomer to the epidermis, it is necessary to buffer the composition by including a suitable buffering agent. Suitable buffering agents are acetic acid/sodium acetate, citric acid/sodium citrate and phosphoric acid/sodium phosphate, and it is desirable generally to buffer the composition to pH 3.0 to 6.0 and preferably, to pH 4.0–5.0. To this end, the buffering agent may preferably be present in an amount of 0.01–1.0% w/w and more preferably 0.05%–0.2% w/w. It is particularly preferred to use a citrate buffer system, and more preferably, anhydrous citric acid/potassium citrate, to buffer the composition to pH 4.5, when betamethasone valerate is used as the active substance; in this case, citrate buffering stabilizes the more active 17-valerate ester over the less active 21-valerate ester in the complex composition and ensures that the most effective form of the active substance is efficiently delivered to the epidermis.
Preparation of the composition may be affected by conventional means, so as to produce a homogeneous solution of fatty alcohol(s) or wax(es), in the alcohol/water base. The relative proportions of the fatty alcohol(s), water/aliphatic alcohol and propellant are conveniently controlled according to conventional means so as o provide a homogeneous clear solution and so as to allow the formation of a suitable quick-break foam. Generally speaking, the fatty alcohol(s), surface active agent, aliphatic alcohol and humectant (when present) are preferably mixed together with the corticosteroid active substance to produce and “alcohol phase”. An “aqueous phase” is preferably produced by mixing the buffering agent and water. These phases are then mixed, preferably in the final container, in the required amounts. The propellant is then added under pressure to produce he composition according to the present invention.
In the case of betamethasone valerate, for example, it is particularly preferred to use a composition comprising cetyl alcohol and octadecan-1-o1 as fatty alcohols, together with Polysorbate 60 surface active agent, with purified water and ethanol as the aliphatic alcohol. The system is preferably buffered with anhydrous citric acid potassium citrate and the propellant is preferably butane/propane. It is generally preferred to choose the proportion of the components to achieve a fixed pressure in the container of around 50–70 psi.
The composition of the present invention may be contained in and dispensed from, a container capable of withstanding the pressure of the propellant gas and having an appropriate valve/nozzle for dispensing the composition as a foam under pressure. If the container is made of metal material likely to suffer corrosion under the action of the composition, the composition may include a corrosion inhibitor as an additive. Thus, the present of a corrosion inhibitor may be necessary if the container is made of tin plate. Suitable corrosion inhibitors include organic acid salts, preferably chosen from sorbic acid, benzoic acid, sodium benzoate and potassium sorbate. If used, the corrosion inhibitor maybe present in amounts of 0.1–15% w/w and more preferably, 0.1–3.0% w/w. In the present invention, aluminum cans are preferred as containers, particularly when utilizing the above-mentioned composition for betamethasone valerate as the corticosteroid active substance; in this case, there is no corrosion problem and there is no need of the inclusion of a corrosion inhibiting agent.
In use, the composition is sprayed, producing a semi-solid (i.e. a foam or mousse) that is suitable for the topical application to the scalp. On application, heat from the skin causes the mousse to break down into liquid form, thus releasing the aliphatic alcohol and corticosteroid active substance which penetrate the skin site, leaving a low amount of residue, many times lower than those obtained when delivering active ingredient from a cream base. This route of administration facilitates the ease of specific local applications, and the composition according to the present invention provides a convenient, controllable and efficient vehicle for delivering active substance to the skin. This gives greater physical control compared to conventional topical corticosteroid formulations, minimizes rubbing of the target site and allows the alcoholic vehicle to penetrate the skin to deliver the active ingredient where it will have the greatest effect.
The composition of the present invention may be used in treating skin diseases that are conventionally treated with corticosteroid active substances. Thus, the composition may be use in the treatment of, inter alia, eczema, infantile eczema, atopic dermatitis, dermatitis herpetiformis, contact dermatitis, seborrheic dermatitis, neurodermatitis, psoriasis and intertrigo. The composition is especially useful in the treatment of scalp psoriasis in human subjects.
The principals of the present invention are illustrated below by means of the following non-limiting example.
A betamethasone valerate formulation having the following composition was prepared:
Ingredient % w/w betamethasone valerate .12 cetyl alcohol BP 1.10 octadecan-1-ol BP 0.50 Polysorbate 60 BP 0.4. ethanol 57.79 purified water 33.69 propylene glycol BP 2.00 citric acid anhydrous BP 0.073 potassium citrate 0.027 butane/propane 4.30 100.000
Alcoholic Phase
Cetyl alcohol (HYFATOL 1698, Efkay Chemicals Limited, London, England), octadecan-1-o1 (HYFATOL 1898, Efkay Chemicals Limited, London, England), Polysorbate 60 (CRILLET 3, Croda Chemicals, North Humberside, England) and ethanol in the appropriate proportions were mixed and heated to about 45° C., with continuous stirring until the mix became clear. Betamethasone valerate BP (Roussel Uclaf, Virtolaye, France) was slowly transferred into the mix, again with continuous stirring until the mix became clear.
Aqueous Phase
Purified water was separately heated to 45° C. and anhydrous citric acid BP and potassium citrate BP transferred to the water, with continuous stirring until dissolved.
The alcoholic and aqueous phases were each filtered through 75μ screens and the required weights filled into a can (epoxy lined aluminum) at room temperature. After attaching a valve, the butane/propane propellant (Propellant P&)) was added to the mix in the can to the required weight, and an actuator added to the valve.
The composition, on being sprayed from the can onto the skin, produces a thermophobic foam which breaks down under heating from the skin to release the active ingredient to the epidermis. The presence of the citrate buffer stabilizes the 17-valerate configuration of the betamethasone valerate over the less active 21-valerate configuration, thus producing a composition which efficaciously delivers the active ingredient to the epidermis and which is particularly suitable for the treatment of psoriasis, especially scalp psoriasis. | A foamable pharmaceutical composition comprising a corticosteroid, a quick-break foaming agent, a propellant and a buffering agent, sufficient to buffer the composition to within the range of pH 3.0 to 6.0 is disclosed. The quick-break foaming agent typically comprises an aliphatic alcohol, water, a fatty alcohol and a surface active agent. Due to the nature of the compositions of the invention, they are especially well-suited for use in the treatment of various skin diseases, and in particular, in the treatment of scalp psoriasis. | 8 |
REFERENCE TO PRIOR APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 09/611,074, filed Jul. 6, 2000 by the same title and same inventor.
BACKGROUND OF THE INVENTION
1) Field of the Invention
The subject matter of this invention is directed to a removable lid for a beverage container and more particularly to a lid that is designed to minimize the possibility of burning a user's mouth during consuming a hot beverage and also substantially prevent accidental spillage of the liquid beverage from the beverage container.
2) Description of the Prior Art
It is exceedingly common within the present day society to utilize beverage containers that are made of paper and plastic that are intended to be used once and then disposed. It is also exceedingly common for individuals to utilize these disposable beverage containers to contain hot beverages such as coffee, tea and hot chocolate. It is common that an individual is mobile while consuming of the beverage as the individual may be walking from one location to another, riding in a car or doing some other activity other than merely sitting. It is common to have a lid substantially enclose the open mouth of the beverage container. The primary function of the lid is to prevent leakage of the beverage which can easily occur when the consumer is moving from one location to another or riding in a car. The movement of the car or the movement of the consumer can cause the beverage to move within the beverage container and be squirted out through the dispensing opening formed within the lid. This spilling of the beverage can be deposited on the consumer's hands and clothing or on articles contained near the consumer, such as on a desk.
Another problem associated with lids of the past is that the hot liquid is dispensed directly from the beverage container, through the dispensing opening into the consumer's mouth. Frequently, the hot liquid is at such an elevated temperature that it can actually cause a burn to occur on the lips of the consumer and within the mouth of the consumer. In the past, there has not been made any effort to construct lids to substantially eliminate the possibility of the consumer being burned.
SUMMARY OF THE INVENTION
A first embodiment of beverage container lid which has an exterior cover and an interior cover, both of which are discoid shaped. The peripheral edge of the interior cover is permanently secured to the peripheral edge of the exterior cover. Located between the interior cover and the exterior cover is a substantially enclosed space. The peripheral edge of the exterior cover is to be removably mounted over the mouth of a beverage container with the liquid of the beverage container to be capable of being moved through an inlet opening formed within the interior cover to then be contained within the substantially enclosed space. The inlet opening is non-centrally located within the interior cover with the forward edge of the inlet opening being located substantially closer to the peripheral edge than the rearward edge of the inlet opening. A partition is attached to the interior cover and is located within the substantially enclosed space. The partition has a top edge which is to be located in contact with the interior surface of the exterior cover. The length of the partition is to be at least equal to the length of the inlet opening which requires that the beverage that passes through the inlet opening must pass around the partition to be located within a gap area defined as being part of the substantially enclosed space. A dispensing opening is formed within the exterior cover and is aligned with the gap area. The beverage from the gap area is to be dispensed exteriorly of the beverage container through this dispensing opening by tilting of the beverage container.
A second embodiment of beverage container lid which also has an exterior cover and an interior cover both of which are discoid. The peripheral edge of the interior cover is permanently secured to the peripheral edge of the exterior cover. Located between the interior cover and the exterior cover is a substantially enclosed space. The peripheral edge of the exterior cover is to be removably mounted over the mouth of the beverage container with the liquid of the beverage container to be capable of being moved through a pair of inlet openings formed within the interior cover to then be contained within the substantially enclosed space. The pair of inlet openings are non-centrally located within the interior cover with the forward edge of the inlet openings being located substantially closer to the peripheral edge than the rearward edge of the inlet openings. A wall assembly in the form of a pair of upstanding members is attached to the interior cover with the upstanding members being located between the pair of inlet openings. Each upstanding member has a top edge which is to be located in contact with the interior surface of the exterior cover. The length of the upstanding members is to be at least equal to the length of the inlet openings which requires that the vast majority of the beverage that passes through the inlet openings must pass around the upstanding members to be located within a gap area defined as being part of the substantially enclosed space. A dispensing opening is formed within the exterior cover and is aligned with the gap area. The beverage from the gap area is to be dispensed exteriorly of the beverage container through this dispensing opening by tilting of the beverage container. Each upstanding member abuts against a raised surface formed on the interior surface of the exterior cover. Each of these raised surfaces includes a groove which permits a small quantity of the beverage to be conducted directly from the substantially enclosed space to be deposited within gap area. These grooves provide an initial quantity of beverage into the gap area when the user is taking his or her first drink. The interior cover also includes a weep hole through which the liquid that is contained within the substantially enclosed space can flow back into the beverage container and thereby be reheated if a substantial length of time has occurred from the most recent consumption. Also formed within the interior cover and the exterior cover is a vent.
The primary objective of the present invention is to construct a beverage container lid which substantially eliminates the possibility of spillage of the beverage from the beverage container upon the beverage container encountering a sudden movement.
Another objective of the present invention is to construct a beverage container lid which substantially eliminates the possibility of a hot beverage burning of the consumer's lips or mouth during consuming of the hot beverage.
Another objective of the present invention is to construct a beverage container lid which can be constructed inexpensively and therefor sold to the ultimate consumer at a relatively inexpensive price.
Another objective of the present invention is to a beverage container lid which is simple in construction and therefore non-complex to manufacture.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, reference is to be made to the accompanying drawings. It is to be understood that the present invention is not limited to the precise arrangement shown in the drawings.
FIG. 1 is an exterior view of a typical beverage container on which has been installed the first embodiment of beverage container lid of the present invention;
FIG. 2 is a top plan view of the first embodiment of beverage container lid of the present invention taken along line 2 — 2 of FIG. 1;
FIG. 3 is a cross-sectional view through the beverage container and the first embodiment of beverage container lid of this invention taken along line 3 — 3 of FIG. 2 showing the beverage container in a normal resting upright position;
FIG. 4 is a view partly in cross-section through the first embodiment of beverage container lid of the present invention taken along line 4 — 4 of FIG. 3;
FIG. 5 is a view similar to FIG. 3 but showing the beverage container in the typical tilted position for consuming of the beverage contained within the beverage container;
FIG. 6 is a top plan view of a second embodiment of beverage container lid of the present invention;
FIG. 7 is a transverse cross-sectional view through the second embodiment of beverage container lid of the present invention taken along line 7 — 7 of FIG. 6;
FIG. 8 is a transverse cross-sectional view through the second embodiment of beverage container lid of the present invention taken along line 8 — 8 of FIG. 7 showing in more detail the flow of the beverage through the dispensing opening; and
FIG. 9 is a view partly in cross-section of the interior surface of the exterior cover of the second embodiment of beverage container lid of the present invention taken along line 9 — 9 of FIG. 8 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring particularly to the drawing, there is shown in FIG. 1 a beverage container 10 that has an internal chamber 12 . Within the internal chamber 12 there is to be located a quantity of a beverage 14 . The beverage container 10 has an open mouth 16 . A typical beverage could be a cold beverage or a hot beverage. However, the structure of the present invention is designed in particular to be used in conjunction with a hot beverage such as tea, coffee or hot chocolate.
The open mouth 16 is to be closeable by a first embodiment of lid 18 . The lid 18 is to be constructed of plastic or other similar type of sheet material such as a paper composition. The lid 18 has an exterior cover 20 and an interior cover 22 . Both the exterior cover 20 and the interior cover 22 are of a discoid shape and are both substantially planar.
However, it is to be within the scope of this invention that the covers 20 and 22 could be other than a discoid shape, such as for an example a square shape or another polygonal shape such as hexagonal or octagonal. Typically, the thickness of the covers 20 and 22 will generally by about one-eighth of an inch.
The interior cover 22 has a peripheral edge which is formed into an annular flange 24 . The upper edge of the annular flange 24 is glued or otherwise fixedly secured, as by heat sealing, to the inside surface of the exterior cover 20 .
Integrally connected to the peripheral edge of the exterior cover 20 is an annular depending flange 26 . In between the depending flange 26 and the annular flange 24 is located an annular groove 28 . The upper edge of the beverage container 10 located at the open mouth 16 is to be snugly located within the annular groove 28 . This will fixedly secure the lid 18 onto the beverage container 10 . However, the lid 18 can be manually disengaged from the beverage container 10 by merely pulling of the lid 18 away from the beverage container 10 .
The interior cover 22 includes an inlet opening 30 . The inlet opening 30 is generally no more than three quarters of an inch to one inch in length and about one quarter of an inch wide. The inlet opening 30 is located in an off center position within the interior cover 22 . The inlet opening 30 has a forward edge 32 and a rearward edge 34 . Upon tilting of the beverage container 10 to a tilted position, such as depicted within FIG. 5, a small quantity of the beverage 14 is to flow through the inlet opening 30 to within the substantially enclosed space 36 formed between the exterior cover 20 and the interior cover 22 .
Fixedly mounted onto the upper surface of the interior cover 22 at the forward edge 32 is a partition 38 . The partition 38 has a top edge that is to be in contact with the interior surface of the exterior cover 20 . The partition 38 comprises an arcuately shaped wall that is about three quarters to an inch long with it be important that the partition 38 be at least as long as the length of the inlet opening 30 . Actually, the partition 38 comprises the “punched out” material of interior cover 12 that forms inlet opening 30 . In between the partition 38 and the annular flange 24 is a gap area 40 . It is to be noted that the gap area 40 is generally no more than a quarter to a half inch wide. This means the partition 38 is located very near the annular flange 24 with there being a substantial amount of space from the rearward edge 34 to the annular flange 24 . The reason for this is so that when the beverage container 10 is tilted is that the beverage 14 will flow through the inlet opening 30 , depicted by arrows 42 , to against the partition 38 and then around the partition 38 is shown by arrows 44 to within the gap area 40 .
Connecting with the gap area 40 is a dispensing opening 46 , which is shown to be of a triangular configuration. The consumer is to locate his or her mouth about the dispensing opening 46 with the upper lip being located in the area of the point 48 and the bottom lip located close to but spaced from the base 50 . The point 48 prevents the beverage, if hot, from contacting to any great extent the upper lip of the consumer. This is so as to protect the upper lip against burning. Although the fact that the beverage has to travel some distance, that is from the inlet opening 30 , around the partition 38 , to within the gap area 40 prior to being dispensed through the dispensing opening 46 . This distance of travel should be sufficient enough to substantially cool the beverage and prevent burning of any portion of the consumer's mouth. Also, the vent holes 52 help to cool the beverage by letting “steam” escape into the ambient.
If the beverage container 10 is jostled or inadvertently tipped over, the fact that the beverage 14 must be conducted through the inlet opening 30 and then through the dispensing opening 46 substantially minimizes the possibility of any accidental dispensing of the beverage 14 . The vent holes 52 are so small that a minimal amount of beverage could flow through these holes 52 into the ambient if the beverage container 10 is tipped over. The purpose of this is to prevent contamination of the consumer's workplace as well as the consumer's clothes and contact with the consumer's person.
Although the partition 38 is shown to be of an arcuate configuration which is believed to help in directing the beverage 42 in the direction of arrows 42 , it is considered to be within the scope of this invention that the partition 38 could be of another configuration, such as a straight configuration or possibly even a convex configuration rather than concave shown in FIG. 4 .
Referring particularly to FIGS. 6-9 of the drawings, there is shown the second embodiment 54 of lid of this invention. The second embodiment 54 includes an exterior cover 56 and an interior cover 58 . Both the exterior cover 56 and interior cover 58 are discoid shape. However, it is considered to be within the scope of this invention that the covers 56 and 58 could be other than a discoid shape. Again, the thickness of the covers 56 and 58 will generally be about one-eighth of an inch.
The exterior cover 56 has an inner surface that defines an internal chamber 60 . Formed within the exterior cover 56 is a dispensing opening 62 . The dispensing opening 62 is positioned directly adjacent the peripheral edge 64 of the exterior cover 56 . Formed integral with the exterior cover 56 and located within the internal chamber 60 and positioned just on one side of the dispensing opening 62 is a raised surface 66 with a similar raised surface 68 being located on the opposite side of the dispensing opening 62 . The raised surface 66 includes a through groove 70 with a similar through groove 72 being formed within the raised surface 68 . The purposes of the through grooves 70 and 72 will be explained further on in the specification. The exterior cover 56 also includes a vent hole 74 . The vent hole 74 may directly connect with the substantially enclosed space 76 of the interior cover 58 or may connect directly with a hole 78 formed within a post 80 which is formed integral with the interior cover 58 . The post 80 is to cause the venting of steam to occur directly from the internal chamber 82 of the beverage container 84 . Hot liquids 86 , such as coffee or tea, are to be contained within the internal chamber 82 .
The exterior cover 56 includes a centrally located indentation 88 . This indentation 88 is for the purpose of giving strength to the overall construction of the exterior cover 56 .
The interior cover 58 also includes a partition in the form of a pair of spaced apart upstanding walls 90 and 92 . Outside of the upstanding wall 92 is located a hole 94 . Outside of the upstanding wall 90 is a hole 96 . In between the walls 90 and 92 is located a gap area 98 . When the interior cover is secured, as by adhesive or sonic welding to exterior cover 56 , the upper surface of the upstanding wall 90 is to rest against the raised surface 66 and the upper surface of the upstanding wall 92 is to rest against the raised surface 68 .
When the beverage container is first tilted and the first drink is to be consumed from the beverage container, there should be no beverage contained within the substantially enclosed space 76 . Also, if it had been some time since the last drink, the beverage 102 that would have been contained within the substantially enclosed space 76 would have leaked back through weep hole 100 into the internal chamber 82 to be intermixed with and reheated by hot beverage 86 . However, when the first drink is being consumed, there will normally be no liquid contained within the substantially enclosed space 76 as it will take some time (a few seconds) for the beverage to pass through the holes 94 and 96 to fill the substantially enclosed space 76 and then flow around the upstanding walls 90 and 92 to fill the gap area 98 . To avoid this few seconds of filling at the time the first drink is taken, the beverage is permitted to flow through the through grooves 70 and 72 directly into the gap area 98 . This initial direct flow of the beverage will then provide an immediate small quantity 104 of the beverage to the user to be consumed. This flowing through the through grooves 70 and 72 will cause a drop in temperature of the beverage so that the beverage is cooled somewhat so as to not be too hot when initially consumed. After the first drink has occurred, there will be contained a quantity 102 of the beverage within the substantially enclosed space 76 . When the user takes another drink, the quantity 102 will then merely flow around the upstanding walls 90 and 92 and fill the gap area 98 with a small quantity 104 . The time that it takes for the beverage to flow into the substantially enclosed space 76 and then around the upstanding walls 90 and 92 into the gap area 98 will result in the quantity 104 to be at a lesser temperature than the quantity 102 of the beverage or the beverage 86 so that the quantity 104 that is being directly consumed will not cause a burning of the consumer's mouth.
The present invention may be embodied in other specific forms without departing from the essential attributes thereof. Reference should be made to the appending claims rather than the foregoing specification as indicating the scope of the invention. | A removable beverage container lid wherein the lid has a substantially enclosed space defined between an exterior cover and an interior cover. At least one inlet opening is formed in the interior cover directing a hot beverage to flow into the substantially enclosed space. Attached to the interior cover at the forward edge of the inlet opening is a partition or wall assembly having a height extending to be located substantially against the exterior cover and a length at least equal to the length of the inlet opening. Between the partition or wall assembly and the peripheral edge of the exterior cover is located a gap area. Connected with the gap area is a dispensing opening formed in the exterior cover. Hot beverage is required to flow around the partition or wall assembly and into the gap area prior to flowing through the dispensing opening exteriorly of a beverage container. | 0 |
BACKGROUND OF INVENTION
[0001] The present invention relates to a method of controlling a hybrid electric automotive powertrain and in particular to a method of timing transmission gearing shifts.
[0002] A hybrid electric powertrain of an automotive vehicle may include both an internal combustion engine and an electric machine to provide propulsion. Commonly, while the vehicle is maintaining a constant cruising speed, the powertrain will stop the engine and use only the machine for propulsion. While at the machine only cruising speed, an acceleration request may be made. Meeting the acceleration request may require both restarting the engine and downshifting a transmission.
[0003] However, the combination of restarting the engine and downshifting may result in a torque shortage that delays meeting the acceleration request. The torque shortage may reduce drivability by causing a driver of the vehicle to experience a sense of deceleration despite making the acceleration request.
SUMMARY OF INVENTION
[0004] An embodiment contemplates a method of controlling a hybrid powertrain. A transmission shift request is received while an electric machine is propelling a vehicle and an engine is stopped. A torque capacity of the machine is determined. Completion of the shift request is timed as a function of the torque capacity relative to a shifting torque required to complete the shift request.
[0005] Another embodiment contemplates a method of controlling a hybrid powertrain. A transmission shift request is received while an electric machine is propelling a vehicle and an engine is stopped. A shifting torque to complete the shift request is determined. A torque capacity of the machine is evaluated. The shift request is completed using the machine to change gearings in a transmission when the torque capacity exceeds the shifting torque. Completing the shift request is delayed while starting the engine when the shifting torque exceeds the torque capacity. The shift request is then completed using the machine and started engine to change gearings in the transmission.
[0006] Another embodiment contemplates a method of controlling a hybrid powertrain. An acceleration request is received while an electric machine is propelling a vehicle and an engine is stopped. A determination is made that downshifting a transmission and starting the engine are needed to meet the acceleration request. A torque capacity of the machine and a shifting torque required to downshift the transmission by changing transmission gearing are determined. Downshifting the transmission is timed as a function of the torque capacity relative to the shifting torque.
[0007] An advantage of an embodiment is that both the starting of the engine and completing of the shift request can be completed without a torque shortage. This improves driveability of the vehicle.
BRIEF DESCRIPTION OF DRAWINGS
[0008] FIG. 1 is a schematic view of a hybrid electric powertrain.
[0009] FIG. 2 is a flow chart of a control routine for a powertrain.
[0010] FIGS. 3 a and 3 b are a flow chart of a control routine for a powertrain.
DETAILED DESCRIPTION
[0011] FIG. 1 schematically illustrates a hybrid electric powertrain 10 for an automotive vehicle 12 . This powertrain 10 is merely exemplary, and may take other forms, which may be front wheel drive, rear wheel drive, or all wheel drive types of powertrains. As described, the powertrain 10 is a parallel type hybrid electric powertrain but may also be another suitable powertrain known to one skilled in the art.
[0012] The powertrain 10 includes an internal combustion engine 14 powering a crankshaft 16 . Interposed between the engine 14 and an electric machine 22 , which may be an electric motor or motor/generator, is an engine disconnect clutch 18 . When engaged, the clutch 18 connects the crankshaft 16 with an electric machine input 20 and transmits torque between the engine 14 and the machine 22 . In turn, the machine 22 transmits torque to a torque converter 26 through a torque converter input 24 and the torque converter 26 transmits torque to a transmission 30 through a transmission input 28 . The transmission 30 includes a plurality of gearings that are changeable to alter the input to output gear ratio, and hence rotational speed and torque output of the powertrain 10 by any suitable technique known to those skilled in the art. The transmission 30 turns a driveshaft 32 which in turn drives a differential 34 . The differential 34 transmits torque to first and second axles 36 and 38 , respectively, which drive first and second wheels 40 and 42 , respectively. A controller 44 controls operation of the powertrain 10 .
[0013] FIG. 2 will now be discussed with reference to FIG. 1 . FIG. 2 illustrates a control routine 100 for the powertrain 10 .
[0014] In a step 102 , the controller 44 receives a shift request for the transmission 30 while the vehicle 12 is being propelled by the machine 22 with the engine 14 stopped. The shift request is made to shift the transmission 30 from a present gear ratio to a new gear ratio. The controller 44 , in a step 104 , determines a shifting torque to complete the transmission shift request and, in a step 106 , a torque capacity of the machine 22 . The shifting torque is a torque required for the transmission 30 to shift from the present gear ratio to the new gear ratio. The torque capacity of the machine 22 may include a torque reserve for starting the engine 14 .
[0015] In a step 108 , the controller 44 determines if the torque capacity is greater than the shifting torque. If the torque capacity is not greater than the shifting torque, then, in a step 110 , the controller 44 delays completing the shift request. In a step 112 , the controller 44 prepares the transmission 30 to complete the shift request. The shift request is prepared by reducing an off going clutch pressure for the present gearing to almost slipping and increasing an oncoming clutch pressure for the new gearing to just below a torque force in the transmission input 28 . While the shift request preparation is completed, the controller 44 starts the engine 14 in a step 114 . Once the engine is running in a step 116 , the controller 44 engages the engine disconnect clutch 18 in a step 118 . The shift request is then completed in a step 122 .
[0016] If, in the step 108 , the torque capacity is greater than the shifting torque, then, in a step 120 , the controller 44 prepares the transmission 30 to complete the shift request. The shift request is then completed in the step 122 .
[0017] FIGS. 3 a and 3 b will now be discussed with reference to FIG. 1 . FIGS. 3 a and 3 b illustrate a control routine 200 for the powertrain 10 .
[0018] In a step 202 , the controller 44 receives an acceleration request for the transmission 30 while the vehicle 12 is being propelled by the machine 22 with the engine 14 stopped. In a step 204 , the controller 44 determines that starting the engine 14 is required to meet the acceleration request and in a step 206 , the controller 44 determines that downshifting the transmission from a higher gearing to a lower gearing is also required to meet the acceleration request. In a step 208 , the controller 44 determines a shifting torque to complete downshifting the transmission and, in a step 210 , a torque capacity of the machine 22 . The shifting torque is a torque required for the transmission 30 to change from the higher gear ratio to the lower gear ratio. The torque capacity of the machine 22 may include a torque reserve for starting the engine 14 .
[0019] In a step 212 , the controller 44 determines if the torque capacity is greater than the shifting torque. If the torque capacity is not greater than the shifting torque, then, in a step 214 , the controller 44 delays completing the downshift. In a step 216 , the controller 44 prepares the transmission 30 to downshift while also, in a step 218 , starting the engine 14 . The transmission 30 is prepared to downshift similarly to how the transmission 30 is prepared to shift for the control routine 100 . Preparing to downshift the transmission 30 in step 216 may be simultaneous with starting the engine 14 in the step 218 . After the engine 14 is running in a step 220 , the clutch 18 is engaged to transmit torque in a step 222 , and in a step 224 , downshifting the transmission 30 is completed. Following downshifting the transmission 30 , the acceleration request is completed in a step 240 .
[0020] If, in the step 212 , the torque capacity is greater than the shifting torque, then in a step 236 the controller 44 prepares the transmission 30 to downshift while, in a step 230 , the engine 14 is started. The transmission 30 is downshifted in a step 228 . Once the engine 14 is running in a step 232 , the clutch 18 is engaged to transmit torque in a step 234 . As illustrated, the steps 226 and 228 comprise a downshift subroutine 236 and the steps 230 , 232 , and 234 comprise an engine start subroutine 238 . The downshift and engine start subroutines 236 and 238 , respectively, may occur simultaneously. Following downshifting the transmission 30 in the step 228 and engaging the clutch 18 in the step 234 , the acceleration request is completed in the step 240 .
[0021] While certain embodiments of the present invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims. | A transmission shift is timed for a hybrid electric powertrain as a function of a torque capacity of an electric machine relative to a shifting torque required to change gearings of a transmission. A vehicle is being propelled by the machine, with an engine stopped, when the shift is requested. If the machine has insufficient torque capacity to change transmission gearings, then the shift request is delayed until the engine has started. | 8 |
This is a continuation of application Ser. No. 926,591 filed Nov. 3, 1986 now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to coupling members that can be quickly latched together and disconnected, and more particularly to a novel coupling assembly that can be depressurized while the coupling members are latched together to permit safe and easy separation of the coupling members.
As used herein the terms "depressurize", "depressurization of the coupling assembly" and "depressurization of the coupling members" are intended to refer to a rapid loss of pressure by one of two coupling members.
Quick disconnect coupling assemblies afford instant utilization of a fluid supply source and allow the fluid supply source to be interconnected with different fluid outlets. Some fluid supply sources, such as pressurized gas tanks will cause a relatively high pressure buildup across the coupling members. Consequently, a quick disconnection of the coupling assembly usually results in a rapid depressurization of the coupling member that is disconnected from the fluid supply source. During such depressurization the coupling member which loses pressure has a tendency to "shoot away" from the other coupling member due to the forces generated when there is a rapid release of pressure.
Because of the risk of injury when one coupling member "shoots away" from another coupling member during disconnection of high pressure couplings, special techniques have been developed for safely disconnecting coupling assemblies that join with a high pressure fluid supply. Such techniques usually require a combination of strength and skill, thus limiting the handling of high pressure couplings to select individuals even though numerous other personnel may be qualified to operate other parts of a fluid flow system that incorporates the high pressure couplings.
One known structure for dealing with the problem of "shoot-away" couplings, as shown in U.S. Pat. No. 4,483,510, is a coupling assembly with a two-stage release mechanism for disconnecting the coupling members. During the first stage of release, a locking element is actuated to permit movement of one of the coupling members away from the other coupling member to an intermediate locked position. As the actuator returns to its original unactuated position, the movable coupling member shifts to a second locked position wherein depressurization can take place. A subsequent actuation of the locking element frees the moveable coupling member to permit disconnection from the coupling assembly.
Although depressurization occurs while the coupling members are locked together, the need to actuate the locking element more than once to accomplish a safe disconnection can be confusing because most coupling assemblies are separable with one actuation of an actuating mechanism.
Another known coupling assembly as shown in U.S. Pat. No. 4,541,457 requires unthreading of the coupling members after fluid flow has been shut off by a poppet valve in the coupling assembly. Although the coupling assembly depressurizes during the unthreading process, there is no quick disconnection of the coupling members.
It is thus desirable to provide a reusable, quick disconnect coupling assembly that can be depressurized with the coupling members latched together and requires only one actuation of a release mechanism to depressurize and separate the coupling members.
OBJECTS AND SUMMARY OF THE INVENTION
Among the several objects of the invention may be noted the provision of a novel coupling assembly, a novel coupling assembly that can be safely and easily uncoupled without one of the coupling members shooting away from the other coupling member, a novel coupling assembly that is depressurized while the coupling members are latched together, a novel coupling assembly that can be depressurized and the coupling members separated from each other with one actuation of an actuating member, a novel coupling assembly that requires release of an actuating member after it has been depressed before the coupling members can be separated, and a novel method for safely disconnecting a coupling assembly.
Other objects and features of the invention will be in part apparent and in part pointed out hereinafter.
In accordance with the present invention, the coupling assembly includes a pair of interengageable and separable coupling members. Moveable latching means are provided on one of the coupling members to engage with latch engaging means provided on the other coupling member. Cooperation between the latching means and the latch engaging means enable the coupling assembly to be placed in at least two separate positions such as a fluid flow position which permits movement of fluid through the coupling members and a depressurization position wherein fluid cannot flow through the coupling members and the coupling assembly depressurizes.
In another embodiment of the invention, the latching means and the latch engaging means cooperate to position the coupling assembly in an intermediate position between the fluid flow position and the depressurization position wherein the coupling assembly remains under pressure but fluid flow is shut off.
Actuating means are provided on one of the coupling members for actuating movement of the latching means in a first direction when the coupling assembly is in the fluid flow position. The actuating means moves the latching means from the first latching position to a second latching position to permit placement of the coupling members in the depressurization position. Biasing means that cooperate with the actuating means return the actuating means to its initial position to permit movement of the coupling members from the depressurization position to an unlatched position that allows separation of the coupling members.
In the preferred embodiment of the invention, the latching means are provided on the female coupling member and the latch engaging means are provided on the male coupling member. The latch engaging means are operable by the actuating means to move transversely to a longitudinal axis of the coupling assembly. The latching means include a pair of latching members that are engageable, in sequence with at least one stop surface provided on the male coupling member.
Engagement of one of the latching members with the stop surface locks the coupling assembly in the fluid flow position, and engagement of the other latching member with the stop surface locks the coupling assembly in the depressurization position.
The latching members have opening therein which are sized to clear the male coupling member. However, the openings in the latching members are out of alignment with each other by a predetermined amount such that when one of the openings in one of the latching members clears the male coupling member the other opening in the other latching member interferes with the male coupling member.
In this manner the interference between at least one of the latching members and the male coupling member results in an engagement between one latching member and the stop surface on the male coupling member to lock the coupling assembly in a predetermined position.
In the other embodiment of the invention, the male coupling member includes two stop surfaces which cooperate with the two latching members to establish three latching positions of the coupling assembly, the additional latching position being the intermediate position wherein the coupling assembly remains pressurized but the fluid flow through the coupling assembly is shut off.
In either embodiment of the invention the actuating member which controls movement of the latching members is actuated only once to accomplish movement of the coupling assembly from the fluid flow position to the depressurization position, to the unlatched position.
In the embodiment of the invention which permits the intermediate latching position between the fluid flow position and the depressurization position, a single actuation of the actuating member will likewise permit movement of the coupling assembly through the three latching positions and the unlatched position that permits separation of the coupling members.
The coupling assembly can thus be quickly depressurized and unlatched with a single actuation of the actuating member in a safe manner by individuals having no special skills or strength.
The invention accordingly comprises the constructions and method hereinafter described, the scope of the invention being indicated in the claims.
DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, in which several embodiments of the invention are illustrated,
FIG. 1 is a simplified perspective view of a coupling assembly incorporating one embodiment of the present invention;
FIG. 2 is a perspective view thereof, with the coupling members separated from each other;
FIG. 3 is an enlarged fragmentary plan view thereof, partly shown in section;
FIG. 4 is an enlarged fragmentary sectional view thereof, with the coupling members engaged to permit fluid-flow;
FIG. 5 is a sectional view taken along the line 5--5 of FIG. 4;
FIG. 6 is a sectional view taken along the line 6--6 of FIG. 4;
FIG. 7 is an enlarged fragmentary sectional view thereof with the coupling members positioned to shut-off fluid flow while under pressure;
FIG. 8 is a view similar to FIG. 7 with the coupling members engaged to permit depressurization;
FIG. 9 is a fragmentary perspective view thereof, partly shown in section;
FIG. 10 is a view similar to FIG. 8 with the coupling members unlatched prior to separation thereof;
FIG. 11 is an enlarged fragmentary sectional view of the coupling members separated from each other;
FIG. 12 is a sectional view taken along the line 12--12 of FIG. 10;
FIG. 13 is a sectional view taken along the line 13--13 of FIG. 10;
FIG. 14 shows a modified poppet valve thereof; and,
FIG. 15 is a fragmentary sectional view of another embodiment of the invention.
Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, a coupling assembly incorporating one embodiment of the invention is generally indicated by the reference number 10 in FIG. 1.
The coupling assembly 10 comprises a hollow male coupling 12 which defines a fluid passage 13, and a female coupling 14. Each of the coupling members are engagable with respective fluid flow lines of connections such as line 15, which is threaded to the female coupling 14.
The male coupling member 12, which can be formed as an integral unit, preferably from stainless steel, includes a nipple 16. As most clearly shown in FIG. 11, the nipple 16 has a reduced finished end 18, a tapered camming section 20 and a narrow section 22. The narrow section 22 is spaced from an enlarged elongated section 24 of identical diameter by annular steps 26 and 28. The steps 26 and 28 form a channel between the narrow and elongated sections 22 and 24, with the step 26 being narrower and of greater diameter than the step 28. An annular collar 29 surrounds the elongated section 24 and can be formed integrally with the elongated section 24.
The female coupling member 14, which is shown separate from the male coupling member 12 in FIG. 11, includes a sleeve 30 which can be formed of plastic such as sold under the designation DELRIN, joined to a coupling body 32 by a set screw 34. The coupling body 32, preferably formed from stainless steel, includes a nipple recess portion 36 (FIG. 11) of complementary size and shape with the nipple 16 to slidably accommodate the nipple 16 of the male coupling 12. An O-ring 38 is provided in the coupling body 32 at the reduced end of the nipple recess 36.
A poppet valve 40, which can also be formed of DELRIN plastic, includes a head portion 42 retained in an inlet space 44 of the coupling body 12. The head portion 42 is formed with a flange 46. An O-ring 48 is provided between the flange 46 and a tapered surface 50 of the coupling body 32 within the confines of the inlet space 44. A hollow body section 52 of the poppet valve 40 extends beyond the head portion 42 toward the O-ring 38. A clearance section 56 is formed in the coupling body 32 near the O-ring 38 and a clearance undercut 58 is formed in the poppet valve 40 between the head portion 44 and the body portion 52.
A plurality of elongated slots such as 60, 62 and 64 are provided in the body portion 52 extending axially along a longitudinal axis 66 of the female coupling member 14 from the head portion 42 of the poppet valve 40 to a skirt portion 68. The body section 52 defines a flow passage 70 that extends from the head portion 42 through the skirt portion 68. It should be noted that further reference to axial distances are intended to refer to the longitudinal axis 66.
An inlet end portion 72 of the female coupling 14, which surrounds the inlet space 44, is threaded at 74 to the fluid line 15 which extends from a fluid source (not shown).
The end portion 72 of the female coupling 14 includes a wire mesh screen 80, preferably formed of brass, sandwiched between a retainer 82 and a spacer ring 84. The retainer 82 is press-fit into the inlet end portion 72 whereas the spacer ring 84 bears against one side of a retaining ring 86. Preferably the retainer 82, the spacer 84 and retaining ring 86 are formed of stainless steel.
A coil spring 88 disposed in the inlet space 44 bears against an opposite side of the retaining ring 86 and the flange 46 of the poppet valve 40. Under this arrangement the coil spring 88 normally urges the poppet valve 40 in a closed condition as shown in FIG. 10 wherein the O-ring 48 seals off communication between the inlet space 44 and the flow space 54.
The female coupling 14 further includes first and second latching rings 90 and 92 which are L-shaped in cross-section as shown in FIG. 4 for example. The latching ring 90 includes a generally elliptical leg portion 94, also referred to as an interference member, having a circular opening 96 sized to accommodate the nipple 16 upon insertion of the male coupling 12 into the female coupling 14. The latching ring 90 also includes a generally rectangular leg portion 98 that is bent 90° with respect to the leg portion 94 and joined to an actuator button 100 by affixation in a slot 102 of the button 100 (FIGS. 5 and 6).
The button 100 is depressible in a recess 104 of the sleeve 30 to enable the elliptical leg portion 94 to move transversely in slots 106 and 107 (FIG. 3). The slots 106 and 107 are defined by oppositely disposed insert pieces 108 and 110 axially spaced from corresponding insert pieces 112 and 114 held in the sleeve 30.
A coil spring 116 based in a recess 118 of the coupling body 32 bears against the leg 98 and normally biases the button 100 to its unactuated position. The coil spring 116 also normally maintains the leg portion 94 in a position wherein the center of the opening 96 is offset from the axis 66 of the female coupling 14, as most clearly shown in FIG. 11.
The latching ring 92 includes a generally elliptical leg portion 120 having a circular opening 122 substantially equivalent in size to the opening 96 of the latching ring 90. The elliptical leg portion 120, also referred to as an interference member, is moveably confined in slots such 124 and 125 (FIG. 3). The slots 124 and 125 are defined between and end portion 126 of the coupling body 32 and the insert pieces 112 and 114.
The latching ring 92 also includes a generally rectangular leg portion 128 that is narrower and shorter than the leg portion 98 of the latching ring 90, and is receivable in a recess 130 (FIG. 6) of the botton 100. A coil spring 132, based in a recess 134 of the coupling body 32 bears against the leg portion 128 to bias the leg portion 128 toward the leg portion 98 of the latching ring 90.
Referring to FIG. 10, the leg portions 128 and 98 normally do not engage when the female coupling 14 is separated from the male coupling 12. In addition, the openings 122 and 96 of the leg portions 120 and 94 are normally misaligned a predetermined amount.
An end portion 136 of the sleeve 30 includes a central access opening 138 for the male coupling 12. The access opening 138 leads to an intermediate space 140 between the sleeve 30 and the coupling body 32. The intermediate space 140 also accommodates movement of the latching rings 90 and 92.
The end portion 136 further includes an annular recess 142 that receives the annular collar 29 of the male coupling 12 when the coupling members 12 and 14 are engaged. A plurality of pressure relief openings 144 and 146 in the end portion 136 extend into the intermediate space 140.
In using the coupling assembly 10, assume that the coupling members 12 and 14 are initially separated from each other such as shown in FIG. 11. Coupling or connection is accomplished by simply pushing the male coupling member 12 into the central access opening 138 of the female coupling member 14 until the nipple 16 is received in the nipple recess portion 36.
Insertion of the male coupling member 12 into the female coupling member 14 does not require external actuation of any mechanism of the female or male coupling members. When the male coupling member 12 is fully inserted in the female coupling member 14 the nipple 16 forces the poppet valve 40 into an open position by shifting the poppet valve to the left as noted from a comparison of FIG. 11 and FIG. 4.
With the poppet valve 40 in an open condition, fluid flows from the fluid source (not shown) through the wire screen 80, to the inlet space 44 past the O-ring 48 and clearance section 58 into the elongated slots 60, 62 and 64 of the poppet valve 40. Fluid then flows through the flow passage 70 of the poppet valve 40 into the passageway 13 of the male coupling 12.
A leak-tight joint between the poppet valve 40 and the male coupling member 12 is established by the O-ring 38 at the skirt portion 56 of the poppet valve 40 and the reduced end portion 18 of the nipple 16.
Referring to FIG. 4, The male coupling member 12 is held in position within the female coupling member 14 to permit fluid flow by engagement between the leg portion 120 of the latching ring 92 and the latch engaging stop surface 27 at the step 26 of the male coupling 12.
The opening 96 of the latching ring 90 is sized to clear the portion of the male coupling member 12 engaged in the female coupling 14. The opening 96 aligns with the male coupling 12 in the fluid flow position. Thus there is no engagement between the latching ring 90 and the male coupling member 12 during conditions of fluid flow from the female coupling member 14 through the male coupling 12.
Referring to FIG. 11, it will be noted that the opening 96 in the latching ring 90 is normally coaxial with the longitudinal axis 66 of the female coupling member 14. Consequently during insertion of the male coupling member 12 into the female coupling member 14, there is sufficient clearance between the male coupling member 12 and the opening 96 to avoid any engagement between the male coupling member 12 and the latching ring 90.
However, the opening 122 of the latching ring 92 which is also sized to clear the portion of male coupling member 12 engaged in the female coupling 14, is normally offset from the longitudinal axis 66 of the female coupling member 14. Consequently during insertion of the male coupling member 12 into the female coupling member 14, the camming portion 20 of the nipple 16 interfers with the leg portion 120 of the latching ring 92 as the nipple 16 passes through the opening 122 within the leg portion 120.
As a result of the interference between the nipple portion 16 and the leg portion 120, the leg portion 120 is cammed in a downward direction with respect to FIG. 11 by the camming section 20 of the nipple 16, in opposition to the force of the biasing spring 116. Thus as the nipple 16 moves through the opening 122 of the latching ring 92, the latching ring 92 exerts an upward force against the camming surface 20, and the short narrow section 22. The latching ring 92, under the influence of the biasing spring 116 snaps against the step 26 and eventually snaps against the step 28 to bear against the stop surface 27 at the step 26 thereby locking the male coupling member 12 into the female coupling member 14 in the fluid flow arrangement of FIG. 4.
The longitudinal dimensions of the nipple 16 of the male coupling member 12 are predetermined such that the reduced end 18 of the nipple 16 urges the poppet valve 40 into the open position of FIG. 4 when the latching ring 92 interferes with and thus latches against the stop surface 27. During engagement of the coupling members 12 and 14 in the fluid flow position, the annular collar 29 of the male coupling 12 engages the annular recess 142 of the female coupling member 14.
To separate the coupling members 12 and 14 and shut off the flow of fluid through the coupling assembly the button 100 is depressed. Referring to FIG. 7 in comparison with FIG. 4, it will be noted that when the button 100 is depressed, the opening 122 of the latching ring 92 clears the step 26 of the male coupling member 12. The opening 96 of the latching ring 90 clears the step 28. Accordingly the coil spring 88 in the inlet space 44 urges the poppet valve 40 to the right along the longitudinal axis 66 by an amount equal to the axial width of the step 26, which can be referred to as the sealing distance.
When the poppet valve 40 has moved longitudinally by an amount equal to the sealing distance, the flange 46 of the head portion 42 forces the O-ring 48 against the tapered surface 50 thereby sealing the inlet space 44 to prevent fluid from flowing past the O-ring 48. In addition, the O-ring 38 maintains a seal around the reduced end portion 18 of the male coupling member 12. Consequently, although fluid flow is shut off when the coupling members are positioned as shown in FIG. 7, the male coupling member 12 remains pressurized.
The coupling assembly 10 is maintained in the position of FIG. 7 by engagement of the leg portion 120 of the latching ring 92 against a latch engaging stop surface 25 at the short narrow section 22. The leg portion 120 is also seated on the step 26 at the opening 122 thus limiting transverse movement of the leg portion 120.
Referring to FIG. 8, further depression of the button 100 operates to depressurize the male coupling member 12. As the button 100 is depressed a predetermined amount beyond the position of FIG. 7 the opening 122 of the latching ring 92 clears the short narrow section 22 of the nipple 16.
However, after the button 100 is depressed a predetermined amount from the position of FIG. 4 the latching ring 90 is simultaneously depressed with the latching ring 92 which causes the opening 96 in the leg portion 94 to interfere with the short narrow section 22, as shown in FIG. 8. The leg portion 94 thus engages against the stop surface 25 to prevent the male coupling member 12 from being removed from the female coupling member 14 as long as the button 100 is held in its depressed position.
Engagement of the leg portion 94 and the stop surface 25 occurs when the male coupling member 12 moves outwardly from the female coupling member 14. Movement of the male coupling member 12 during depressurization usually causes such engagement.
The male coupling member 12 in its movement from the position of FIG. 7 to the position of FIG. 8, moves an axial distance equal to the distance between corresponding surfaces of the leg portions 120 and 94. As a result of such movement, the reduced end 18 of the nipple 16 is spaced from the O-ring 38 as well as the body portion 52 of the poppet valve 40. Pressure within the passage 13 of the male coupling 12 is then permitted to escape at the reduced end 18 of the nipple 16 for exhaustion through the nipple recess portion 36, the intermediate space 140 and the pressure relief openings 144 and 146.
Depressurization of the male coupling member 12 thus occurs while the coupling member 12 is latched to the female coupling member 14 by engagement of the latching ring 90 against the stop surface 25 of the male coupling member 12.
Referring to FIG. 11 in comparison with FIG. 8, release or deactuation of the button 100 enables the biasing springs 118 and 134 to urge the respective latching rings 90 and 92 into their normal positions wherein the opening 96 of the latching ring 90 aligns with the longitudinal axis 66 of the female coupling member 14. The normal position of the latching ring 92 provides a misalignment of the opening 122 with the longitudinal axis 66.
However, as the latching ring 92 moves into interference with the nipple 16 during release of the button 100, the opening 122 encircles and engages the camming section 20. Since the widest portion of camming section 20 is moved away from the latching ring 92, such interference does not prevent withdrawal of the male coupling member 12 from the female coupling member 14 to a separation condition as shown in FIG. 11.
As the male coupling member 12 is depressurized while still latched to the female coupling member 14 and depressurization occurs before separation of the male coupling 12 from the female coupling member 14, there is no "shooting away" of the male coupling member 12 from the female coupling member 14 during separation of the coupling members. Thus, the process of shutting off fluid flow from the female coupling member 14 to the male coupling member 12 and the depressurization of the male coupling member 12 are accomplished with one depression of the button 100. The separation of the male coupling member 12 from the female coupling member 14 is further accomplished when the botton 100 is deactuated or released from its depressed condition, and returns to its unactuated position. Consequently only one actuation cycle of the button 100 is required for separation of the coupling members thereby providing a quick and a safe uncoupling of the coupling assembly.
In another embodiment of the invention, the poppet valve 40 of the coupling assembly 10 is replaced by the poppet valve 150 of FIG. 14.
Referring to FIG. 14, the poppet valve 150 includes a head portion 152 with a flange 154 and a body portion 156 extending from the head portion 152. Although not shown, when the poppet valve 150 is positioned in the female coupling 14, the head portion 152 is disposed in the head space 44 with the flange 154 engaging the spring 88.
A peripheral channel 158 is formed in the head portion 152 to accommodate an O-ring 160. The body portion 156 is open-ended with an end taper 162 and includes a flow passage 164 that communicates with peripheral ports such as 166, 168 and 170. The outside diameter of the body portion 156 is sized to permit slideable movement in the flow space 54 of the female coupling 14 in a manner similar to that described for the poppet valve 40. An end portion of the O-ring 160 seals against the tapered surface 50 of the female coupling 14 to shut off fluid flow when the male coupling 12 is separated from the female coupling 14.
In using the poppet valve 150 of FIG. 14 in a coupling assembly arrangement similar to that shown in FIG. 4, fluid flows past the poppet valve flange 154 into the ports 166, 168 and 170 and through the flow passage 164 to the male coupling 12. Operation of a coupling assembly using the poppet valve 150 is otherwise similar to the operation described for the coupling assembly 10.
A coupling assembly incorporating another embodiment of the invention is generally indicated by the reference number 180 in FIG. 15. The coupling assembly 180 includes a male coupling member 182, and a female coupling member 184 identical to the female coupling member 14.
The male coupling member 182 includes a nipple 186 having a reduced finished end 188, a tapered camming section 190 and a narrow section 192 similar to the finished end 18, the tapered camming section 20 and the narrow section 22 of the nipple 16. The narrow section 192 is spaced from an enlarged elongated section 194 of identical diameter by a reduced section 196. An annular channel 198 is thus defined between the narrow section 192 and the enlarged elongated section 194.
The remaining structure of the male coupling member 182 is similar to that of the male coupling member 12.
In using the coupling assembly 180, the male coupling member 182 is fully inserted into the female coupling member 184 as shown in FIG. 15, wherein the latching ring 92 bears against a latch engaging stop surface 193 at an end of the enlarged narrow section 192 within the annular channel 198. The latching ring 192 thus latches the male coupling member 182 to the female coupling member 184 in a position which permits fluid to flow through the coupling assembly 180.
The reduced finished end 188 of the nipple 186 thus forces the poppet valve 40 into an open condition wherein fluid flows through the inlet space 44 into the flow passage 70 and through the fluid passage 13 of the male coupling member 182.
In the fluid flow arrangement of FIG. 15, there is no engagement between the latching ring 90 and the male coupling member 182, since the opening 96 of the latching ring 90 clears the male coupling member 182 and normally aligns with the longitudinal axis 66 of the coupling assembly 180. Thus there is no interference between the latching ring 90 and the male coupling member 182 during insertion of the male coupling member 182 into the female coupling member 184.
The opening 122 in the latching ring 92 is normally out of alignment with the opening 96 and also misaligns with the longitudinal axis 66 of the coupling assembly 180. The opening 122 thus interferes with the nipple 186 during insertion of the male coupling member 182 in the female coupling member 184. The tapered camming section 190 of the nipple 186 cams the latching ring 92 along the peripheral surface of the nipple 186 to permit the latching ring 92 to snap into the annular channel 198 and engage the stop surface 193 when the male coupling member 182 is fully engaged in the female coupling member 184.
When it is desired to separate the male coupling member 182 from the female coupling member 184 the button 100 is depressed to effect simultaneous downward movement of the latching rings 90 and 92.
Depression of the latching ring 92 places the opening 122 into alignment with the longitudinal axis 66 of the coupling assembly and also places the opening 96 of the latching ring 90 out of alignment with the longitudinal axis 66. The opening 122 in the latching ring 92 thus clears the male coupling member 182, enabling the spring 88 in the inlet space 44 to urge the poppet valve 40 into a closed position and also force the nipple 186 of the male coupling member 182 to the right with reference to FIG. 15.
As long as the button 100 is depressed, the nipple 186 is limited in its movement to the right by interference between the latching ring 90 and the stop surface 193. Although this interference condition or latching position is not shown, the interference between the latching ring 90 and the stop surface 193 occurs when the male coupling member 182 moves outwardly from the female coupling member 184. Such engagement usually occurs during depressurization.
Thus, when the button 100 is depressed, the male coupling member 182 cannot be separated from the female coupling member 184 even though fluid flow to the male coupling member 182 has been shut off by the poppet valve 40. However, the axial distance travelled by the male coupling member 182 to the right, with reference to FIG. 15, is predetermined by the distance between corresponding surfaces of the leg portion 94 and 120. This distance is predetermined to permit the reduced end 188 of the nipple 186 to unseal from the O-ring 38 and allow the male coupling member 182 to depressurize. Depressurization occurs when fluid within the passage 13 of the male coupling member 182 is permitted to escape at the reduced end 18 of the nipple 186 for exhaustion through the nipple recess portion 36 and out the pressure relief openings 144 and 146.
Separation of the male coupling member 182 from the female coupling member 184 is accomplished when the button 100 is deactuated or released to enable the opening 96 of the latching ring 90 to align with the longitudinal axis 66 and thereby clear the portion of the male coupling 182 engaged in the female coupling 184. Clearance between male coupling 182 and the opening 122 of the latching ring 92 is accomplished when the button 100 is initially depressed.
Since the latching rings 90 and 92 no longer interfere with the nipple 186 of the male coupling member 182, separation of the male coupling member 182 is accomplished by pulling the male coupling member 182 from the female coupling member 184.
Consequently, there is no shooting away of the male coupling member 182 from the female coupling member 184 during the separation of the coupling members since the coupling members are latched together during the depressurization operation.
Some advantages of the present invention evident from the foregoing description include a coupling assembly that can be used on high pressure fluid systems by personnel that require no special skills or training, a coupling assembly that can be fully depressurized while the coupling members are latched together, and a coupling assembly that can be quickly and safely disconnected with one actuation of a release button.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes can be made in the above constructions and method without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. | A coupling assembly includes a female coupling member that can be connected to a fluid supply source and a male coupling member that can be quickly coupled to the female coupling member and quickly separated from the female coupling member. A pair of spaced latching members provided on the female coupling member move transversely with respect to a longitudinal axis of the coupling assembly into and out of engagement with one or more latch engaging surfaces on the male coupling member. The latching members have openings that are out of alignment with each other. An actuating button on the female coupling member is arranged to move the latching members in predetermined fasion to permit the openings in each of the latching members to sequentially interfere with the latch engaging surface or surfaces on the male coupling member to establish sequential latching positions. The sequential latching positions permit placement of the coupling assembly in a fluid flow position, a depressurization position and an unlatched position which permits separation of the coupling members. A further embodiment of the invention permits placement of the coupling assembly in an intermediate position between the fluid flow position and the depressurization position wherein the coupling assembly remains pressurized but fluid flow is shut off. The further embodiment includes a pair of stop surfaces on the male coupling members which interengage with the latching members. The coupling assembly is thus depressurized while the coupling members are latched together and a single actuation of the actuating button permits the coupling assembly to pass through each of the latching positions in a predetermined sequence before the coupling members are unlatched. Quick and safe uncoupling is thus accomplished. | 5 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention generally relates to break-away couplings for lighting poles or appurtenances mounted along highways and roadways and, more specifically, to such a break-away coupling with enhanced fatigue properties.
[0003] 2. Description of the Prior Art
[0004] Many highway and roadside appurtenances, such as lighting poles, signs, etc., are mounted along highways and roads. Typically, these are mounted on and supported by concrete foundations, bases or footings. However, while it is important to securely mount such roadside appurtenances to withstand weight, wind, snow and other types of service loads, they do create a hazard for vehicular traffic. When a vehicle collides with such a light pole or sign post, for example, a substantial amount of energy is normally absorbed by the light pole or post as well as by the impacting vehicle unless the pole or post is mounted to fail at the base. Unless the post is deflected or severed from the base, therefore, the vehicle may be brought to a sudden stop with potentially fatal or substantial injury to the passengers. For this reason, highway authorities almost universally specify that light poles and the like must be mounted in such a way that they must fail at the support structure upon impact by a vehicle.
[0005] In designs of such break-away couplings several facts or considerations come into play. The couplings must have maximum tensile strength with predetermined (controlled) resistance to lateral impact load. Additionally, the couplings must be easy and inexpensive to install and maintain. They must, of course, be totally reliable.
[0006] Numerous break-away systems have been proposed for reducing damage to a vehicle and its occupants upon impact. For example, load concentrated break-away couplings are disclosed in U.S. Pat. Nos. 3,637,244, 3,951,556 and 3,967,906 in which load concentrating elements eccentric to the axis of the fasteners, for attaching the couplings to the system oppose the bending of the couplings under normal loads while presenting less resistance to bending of the coupling under impact or other forces applied near the base of the post. In U.S. Pat. Nos. 3,570,376 and 3,606,222, structures are disclosed which include a series of frangible areas. In both cases, the frangible areas are provided about substantially cylindrical structures. Accordingly, while the supports may break along the frangible lines, they do not minimize forces for bending of the posts and, therefore, generally require higher bending energies, to the possible determent of the motor vehicle.
[0007] In U.S. Pat. No. 3,755,977, a frangible lighting pole is disclosed which is in a form of a frangible coupling provided with a pair of annular shoulders that are axially spaced from each other. In a sense, the annular shoulders are in the form of internal grooves. A tubular section is provided which is designed to break in response to a lateral impact force of an automobile. The circumferential grooves are provided along a surface of a cylindrical member.
[0008] A coupling for a break-away pole is described in U.S. Pat. No. 3,837,752 which seeks to reduce maximum resistance of a coupling to bending fracture by introducing circumferential grooves on the exterior surface of the coupling. The distance from the groove to the coupling extremity is described as being approximately equal to or slightly less than the inserted length of a bolt or a stud that is introduced into the coupling to secure the coupling, at the upper ends, to a base plate that supports the post and to the foundation base or footing on which the post is mounted. The grooves are provided to serve as a stress concentrators for inducing bending fracture and to permit maximum effective length of moment arm and, therefore, maximum bending movement. According to the patent, the diameter of the neck is not the variable to manipulate in order to achieve the desired strength of the part, as the axial (tensile/compressive) strength is also affected.
[0009] However, the above mentioned couplings have shown signs of limited fatigue strength and, therefore, premature failure. Fatigue strength is a property of break-away couplings that has not always been addressed by the industry, partly because of the complex nature of the problem and its solution.
[0010] U.S. Pat. No. 5,474,408, assigned to Transpo Industries, Inc., the assignee of the present invention, discloses a break-away coupling with spaced weakened sections (Alternative Coupler). The controlled break in region included two axially spaced necked-down portions of smaller diameter and solid cross section. The dimensions of the coupling were selected so the ratio D/L is within the range V/L<=0.3 where L is the axial control breaking region and the necked-portion has a diameter D. The necked-portions have conical type surfaces to assure that at least one of the necked-portions break upon bending prior to contact between any surfaces forming or defining the necked-portions.
[0011] A multiple necked-down break-away coupling has been disclosed in U.S. Pat. No. 6,056,471 assigned to Transpo Industries, Inc., in which a control breaking region is provided with at least two axial spaced necked-portions co-axially arranged between the axial ends of the coupling (alternative coupler). Each necked-portion essentially consists of two axially aligned conical portions inverted one in the relation to the other and generally joined at their apices to form a generally hour-glass configuration having a region of a minimum cross section at an inflection point having a gradually curved concave surface defining a radius of curvature. Each of the necked-down portions have different radii of curvature that are at respective inflection points to provide preferred failure modes as a function of a position in direction of the impact of a force.
[0012] The prior patented steel couplings will be referred to as “Existing” for the one Transpo Industries has used in the field for the last 30 years and “Alternative” for the more recently developed coupling. However, these “Existing” and “Alternative” couplings have shown signs of limited fatigue strength. Therefore, a new coupling design was sought that would show marked improvements in fatigue strength.
SUMMARY OF THE INVENTION
[0013] It is, accordingly, an object of the present invention to provide a fatigue-enhanced break-away coupling for a highway or roadway appurtenance which does not have the disadvantages inherent in comparable prior art break-away couplings.
[0014] It is another object of the present invention to provide a fatigue enhanced break-away coupling which is simple in construction and economical to manufacture. It is still another object of the present invention to provide a break-away coupling of the type under discussion that is simple to install and requires minimal effort and time to install in the field.
[0015] It is yet another object of the present invention to provide a fatigue-enhanced break-away coupling as in the aforementioned objects which is simple in construction and reliable, and whose functionality is highly predictable.
[0016] It is yet another object of the present invention to provide a fatigue-enhanced break-away coupling as in the previous objects which can be retrofitted to most existing break-away coupling systems.
[0017] It is still a further object of the present invention to provide a fatigue-enhanced break-away coupling that minimize forces required to fracture the coupling in bending while maintaining safe levels of tensile and compressive strength to withstand non-impact forces, such as wind load.
[0018] It is yet a further object of the present invention to provide fatigue-enhanced break-away couplings of the type suggested in the previous objects which essentially consists of one part and, therefore, requires minimal assembly in the field and handling of parts.
[0019] It is an additional object of the present invention to provide a break-away coupling as in the above objects geometrically optimized to enhance the fatigue properties of the coupling.
[0020] In order to achieve the above and additional objects a break-away coupling in accordance with the invention is formed of metal and has a central axis and a necked-down central region formed by two inverted truncated cones each having larger and smaller bases. The cones are joined at the smaller bases by a narrowed transition region having an exterior surface formed by a curved surface of revolution having an inflection point of minimum diameter substantially midway of the coupling along said axis, said cones each defining an angle θ 1 and θ 2 , respectively, at each of said larger bases, wherein both θ 1 and θ 2 are selected to be less than 40°, such as within the range of 20°-40°, and, preferably, within the range of 30°-37°.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Those skilled in the art will appreciate the improvements and advantages that derive from the present invention upon reading the following detailed description, claims, and drawings, in which:
[0022] FIG. 1 illustrates a typical geometry of a necking region of a double cone coupler and the component pails thereof;
[0023] FIG. 2 is a schematic of a necking region with an elliptic torus surface of revolution;
[0024] FIGS. 3( a )- 3 ( c ) are snapshots of finite element models of double cone couplers with an elliptic torus (a/b=0.65) surface of revolution and three different base angles;
[0025] FIGS. 4( a )- 4 ( c ) are snapshots of finite element models of double cone couplers with an elliptic torus (a/b=1.0) surface of revolution and three different base angles;
[0026] FIGS. 5( a )- 5 ( c ) are snapshots of finite element models of double cone couplers with an elliptic torus (a/b=1.5) surface of revolution and three different base angles;
[0027] FIG. 6 is a schematic of a necking region with a hyperboloid surface of revolution;
[0028] FIGS. 7( a )- 7 ( c ) are snapshots of finite element models of double cone couplers with a hyperboloid (c/d=3) surface of revolution and three different base angles;
[0029] FIGS. 8( a )- 8 ( c ) are snapshots of finite element models of double cone couplers with a hyperboloid (c/d=4) surface of revolution and three different base angles;
[0030] FIGS. 9( a )- 9 ( c ) are snapshots of finite element models of double cone couplers with a hyperboloid (c/d=5) surface of revolution and three different base angles;
[0031] FIG. 10 is a schematic of a necking region with a catenoid surface of revolution;
[0032] FIGS. 11( a )- 11 ( c ) are snapshots of finite element models for double cone couplers with a catenoid surface of revolution and three base angles;
[0033] FIG. 12 is a schematic of a necking region with a elliptic torus surface of revolution and two different base angles;
[0034] FIG. 13( a )- 13 ( f ) are snapshots of finite element models for unequal double cone couplers with an elliptic torus surface of revolution and different combinations of base angles;
[0035] FIG. 14 is a schematic representation for a coupler geometry with equal base angles showing the location of the critical points used for computing stress gradients;
[0036] FIG. 15 is a schematic representation for a coupler geometry with unequal base angles showing the location of the critical points used for computing stress gradients;
[0037] FIGS. 16( a )- 16 ( c ) illustrate the dimensions for two-cone couplers with different surfaces of revolution;
[0038] FIGS. 17( a )- 17 ( c ) illustrate the sensitivity analysis on the coupler's dimensions with different surfaces of revolution;
[0039] FIGS. 18( a )- 18 ( c ) illustrate the Von Mises stresses at the ends of the cone for different surfaces of revolution;
[0040] FIGS. 19( a )- 19 ( c ) illustrate the stress gradients at the transition zones within the cone for different surfaces of revolution;
[0041] FIGS. 20( a )- 20 ( c ) illustrate the combined objective functions for different base angle values showing the significant drop in objective function values of the proposed design interval θ=[30°-37°] compared with current design θ=45° for different surfaces of revolution;
[0042] FIGS. 21( a )- 21 ( c ) are snapshots of (a) EF, (b) EF-Mod-A, and (c) EF-Mod-B couplers;
[0043] FIG. 21( d ) is a rendering of an EF coupler in accordance with the invention having two base angles equal to 32°;
[0044] FIG. 21( e ) is a fragmented enlarged view of the neck portion of the coupler shown in FIG. 21 ( d );
[0045] FIG. 21( f ) is similar to FIG. 21( d ) for a modified EF coupler-Mod-A;
[0046] FIG. 21( g ) is similar to FIG. 21( e ) for the Mod-A coupler shown in FIG. 21( f );
[0047] FIG. 21( h ) is similar to FIG. 21( f ) but for a modified EF coupler-Mod-B;
[0048] FIG. 21( i ) is similar to FIGS. 21( e ) and 21 ( g ) for the Mod-B coupler shown in FIG. 21( h );
[0049] FIG. 22 is a snapshot of the fatigue test setup;
[0050] FIG. 23 illustrates the fatigue testing protocols, showing the mean and amplitude of the fatigue load cycles for test protocols 1-4 used to evaluate tested couplers;
[0051] FIG. 24 illustrates the fatigue testing protocols, showing the mean and amplitude of the equivalent fatigue stress cycles for test protocols 1-4 used to evaluate tested couplers;
[0052] FIG. 25 is a snapshot of five fractured EF couplers tested in Test Protocol-4;
[0053] FIG. 26 is a snapshot of EF Mod-A couplers tested in Test Protocol-4;
[0054] FIG. 27 is a snapshot of EF Mod-B couplers tested in Test Protocol-4;
[0055] FIG. 28 is a chart comparing the fatigue performance of the three couplers (Existing, Alternative and EF);
[0056] FIG. 29 is a chart comparing the fatigue performance of the five couplers under testing protocol-4 including the two EF Mod-A and Mod-B couplers;
[0057] FIG. 30 illustrates the Mean Stress Equivalent S-N curve for the EF, Existing, and Alternative couplers;
[0058] FIG. 31 illustrates the Stress Range Equivalent S-N curve for the EF, Existing, and Alternative couplers;
[0059] FIG. 32 is a snapshot of an EF 6 Failure at 430,150 cycles (mean load=9.40 kip; mean stress=34.85 ksi);
[0060] FIG. 33 is a snapshot of an EF 7 Failure at 439,150 cycles (mean load=9.40 kip; mean stress=34.85 ksi);
[0061] FIG. 34 is a snapshot of an EF 9 Failure at 440,114 cycles (mean load=9.40 kip; mean stress=34.85 ksi);
[0062] FIG. 35 is a snapshot of an EF 10 Failure at 404,763 cycles (mean load=9A0 kip; mean stress=34.85 ksi);
[0063] FIG. 36 is a snapshot of an EF 15 Failure at 453,966 cycles (mean load=9A0 kip; mean stress=34.85 ksi);
[0064] FIG. 37 is a snapshot of an EF 21 Failure at 861,697 cycles (mean load=7.88 kip; mean stress=29.22 ksi);
[0065] FIG. 38 is a snapshot of an EF 24 Failure at 411,064 cycles (mean load=7.88 kip; mean stress=29.22 ksi); and
[0066] FIG. 39 is a snapshot of an EF 25 Failure at 666,331 cycles (mean load=7.88 kip; mean stress=29.22 ksi).
DETAILED DESCRIPTION
Introduction
[0067] Transpo Industries Inc. has designed and patented two steel couplers in 1985 and 2000. The 1985 Coupler is described in U.S. Pat. No. 4,528,786 and will be referred to as the “Existing” coupler that Transpo Industries has used in the field for the last 30 years. The 2000 coupler is described in U.S. Pat. No. 6,056,471 and will be referred to as “Alternative” for the more recently developed coupler. However, these couplers were designed for enhanced mechanical performance but not specifically for fatigue properties. This application describes a geometry for couplers to enhance their fatigue performance over previous couplers. The geometrical design process recognizes a geometrical design range “interval” where the fatigue performance of couplers is expected to significantly exceed that of the “Existing” and the “Alternative” couplers.
[0068] The objective of this work was to design a coupler geometry that significantly increases the fatigue strength of existing couplers. Couplers designed in accordance with the present invention that improve fatigue strength properties will be designated herein as “enhanced fatigue” couplers or “EF” couplers. The process aims to reduce the stress gradients within the necking region. These stress gradients are believed to control the fatigue life of the couplers. High stress gradients result in premature fatigue failure under cyclic loads.
[0069] The typical geometry for the necking region of a double cone coupler consists of two cones and a surface of revolution as shown in FIG. 1 .
[0070] In particular, the objective of the design process was to:
[0000] 1—Determine the significance and select the type of surface of revolution of the necking region. Three types of surfaces of revolution were examined. The three types are elliptic torus, hyperboloid, and catenoid. Different surfaces of revolution yielded different curvature profiles through the depth of the necking region which in turn affected the stress gradients in the necking region.
2—Identify the effect and value(s) of geometric designs including different base angles θ 1 , θ 2 . It is explained below how all the other design variables (dimensions) are based on the base angles θ given the problem constraints to keep the base diameter, the neck diameter and the coupler height constant to satisfy other critical requirements of the couplers.
3—Examine the significance of using unequal base angles θ 1 , θ 2 on the stress gradients in the necking region. This included developing two sets of design variables (dimensions) for the two halves of the necking region. In this study, elliptic torus surface of revolution is selected as a case study for creating the surface of revolution. However, similar findings could be observed for all surfaces of revolution with unequal base angles.
Geometrical Considerations
[0071] Several geometric variables were defined for the design effort. These variables include the base angle (θ), the constants of the surface curvature, the depth of the cone (h 1 ), and half the depth of the surface of revolution (h 2 ). Assuming that the origin is located at the mid height and width of the necking region, there are three other characteristic points that determines the geometry of the necking region. These are A, B, and D. Geometrical relationships were developed for each type of surface of revolution as discussed in this section. To develop these relationships, three geometrical constraints were imposed to all necking region geometries. These constraints are described below.
1) The first constraint implies that the necking diameter remains constant (0.582″) to maintain the same shear design capacity of the couplers. Therefore, the coordinates of point A is set as (0.291″,0). 2) The diameter of the base is also maintained constant of 1.625″. This is necessary to keep the diameter of the coupler unchanged. Therefore, the coordinates of point D is (0.812″, 0.57″). 3) The depth of the necking region is maintained 0.572″ as described by Eqn. (1). In addition, Eqn. (2) describes the limitation for minimum practical depths of h 1 and h 2 .
[0000] h 1 +h 2 =0.57″ (1)
[0000] h 1 and h 2 ≦0.05″ (2)
4) The surface of the cone is maintained tangent to the surface of revolution at point B. This constraint guarantees smooth transition for the stresses between the cone and the surface of revolution. Based on the geometrical constraints, the geometrical relationships were developed for each surface of revolution. The case of equal base angles is covered in subsections (a), (b), and (c) while the case of unequal base angles is covered in subsection (d).
[0076] (a) Equal Elliptic Torus
[0077] The development of the surface of the necking region was obtained by rotating a tangent line and elliptic torus 360° about the couplers longitudinal axis as shown in FIG. 2 . The elliptic torus is characterized by its horizontal and vertical axes (a and b) and its center location at point C (0.291+a,0). Three horizontal-to-vertical axes ratios (a/b) are examined in the optimization process; 0.65, 1.0, and 1.5. The following set of equations is developed for the geometrical relationships of the necking region based on the geometrical constrains and the elliptic torus characteristics.
[0078] Definition of horizontal-to-vertical axes ratio
[0000] a/b= 0.65, or 1.5 (3)
[0079] Base angle is the slope of the tangent
[0000] m =tan θ (4)
[0080] Total depth of necking region is 0.57″
[0000] h 1 +h 2 =0.57″ (5)
[0081] Points B (x B , h 2 ) and Point D (0.812,0.57) satisfies the tangent equation
[0000] y D =m·x D +c (6)
[0000] y B =m·x B +c (7)
[0082] Points B (x B , h 2 ) satisfies the elliptic torus equation
[0000]
(
x
B
-
0.291
-
a
)
2
a
2
+
(
y
B
)
2
b
2
=
1
(
8
)
[0083] Tangency condition at point B.
[0000]
Discriminant
of
[
(
x
-
0.291
-
a
)
2
a
2
+
(
m
·
x
+
c
)
2
b
2
=
1
]
=
0
(
9
)
[0084] The geometry of the necking region of the coupler was obtained by solving the aforementioned seven simultaneous equations (Eqns 3 to 9) to find the seven geometrical parameters (a,b,c,x B ,h 1 ,h 2 ,m). Table (1) to (3) show the calculated geometrical parameters for some base angles with different a/b ratios while FIGS. 3( a )- 5 ( c ) show the corresponding snapshots of the EF models.
[0000]
TABLE (1)
Geometrical parameters for necking region with elliptical
torus (a/b = 0.65)
Base angle
Cone depth
Elliptic torus
Horizontal
Vertical axes
θ, degree
(h 1 ), inch
depth (h 2 ), inch
axis (a), inch
(b), inch
20
0.102
0.468
0.312
0.481
30
0.206
0.364
0.252
0.388
40
0.373
0.196
0.145
0.224
[0000]
TABLE (2)
Geometrical parameters for necking region with elliptic torus (a/b = 1.0)
Elliptic torus
Base angle θ,
Cone depth
depth (h 2 ),
Horizontal
Vertical axes
degree
(h 1 ), inch
inch
axis (a), inch
(b), inch
20
0.058
0.513
0.546
0.546
30
0.165
0.406
0.469
0.469
40
0.350
0.221
0.289
0.289
[0000]
TABLE (3)
Geometrical parameters for necking region with elliptic torus (a/b = 1.5)
Elliptic torus
Base angle θ,
Cone depth
depth (h 2 ),
Horizontal
Vertical axes
degree
(h 1 ), inch
inch
axis (a), inch
(b), inch
20
0.0073
0.562
0.961
0.641
30
0.124
0.445
0.883
0.589
40
0.333
0.237
0.571
0.381
[0085] (b) Equal Hyperboloid
[0086] The development of the surface of the necking region was obtained by rotating a tangent line and a hyperbola 360° about the coupler's longitudinal axis as shown in FIG. 6 . The hyperbola is characterized by its horizontal and vertical semi-axes (c and d) and its symmetric axis location passing through point k (x k ,0). Three horizontal-to-vertical semi-axes ratios (c/d) are examined in the optimization process; 3, 4, and 5. The following set of equations is developed for the geometrical relationships of the necking region based on the geometrical constrains and the hyperbola characteristics.
[0087] Definition of horizontal-to-vertical semi-axes ratio
[0000] c/d= 3,4 or 5 (10)
[0088] Base angle is the slope of the tangent
[0000] m =tan θ (11)
[0089] Total depth of necking region is 0.57″
[0000] h 1 +h 2 =0.57″ (12)
[0090] Points B (x B , h 2 ) and D (0.812,0.57) satisfies the tangent equation
[0000] y D =m·x D +n (13)
[0000] y B =m·x B +n (14)
[0091] Points B (x B , h 2 ) satisfies the elliptic torus equation
[0000]
(
x
B
-
x
k
)
2
c
2
-
(
y
B
)
2
d
2
=
1
(
15
)
[0092] Center of Symmetry of hyperbola point k (x k ,0)
[0000] x k +c= 0.291 (16)
[0093] Tangency condition at point B.
[0000]
Discriminant
of
[
(
x
-
x
k
)
2
c
2
+
(
m
·
x
+
n
)
2
d
2
=
1
]
=
0
(
17
)
[0094] The geometry of the necking region of the coupler was obtained by solving the aforementioned eight simultaneous equations (Eqns 10 to 17) to find the eight geometrical parameters (c,d,n,x B ,h 1 ,h 2 ,x k ). Table (4) to (6) show the calculated geometrical parameters for some base angles with different c/d ratios while FIGS. 7 to 9 show the corresponding snapshots of the EF models.
[0000]
TABLE (4)
Geometrical parameters for necking region with hyperboloid (c/d = 3)
Base
Horizontal
angle θ,
Cone depth
Hyperboloid
semi axis (c),
Vertical semi
degree
(h 1 ), inch
depth (h 2 ), inch
inch
axes (d), inch
32
0.036
0.533
2.537
0.845
38
0.226
0.343
2.182
0.727
45
0.469
0.101
0.856
0.285
[0000]
TABLE (5)
Geometrical parameters for necking region with hyperboloid (c/d = 4)
Base
Horizontal
angle θ,
Cone depth
Hyperboloid
semi
Vertical semi
degree
(h 1 ), inch
depth (h 2 ), inch
axis (c), inch
axes (d), inch
32
0.058
0.511
4.683
1.170
38
0.235
0.334
3.966
0.991
45
0.470
0.099
1.543
0.3857
[0000]
TABLE (6)
Geometrical parameters for necking region with hyperboloid (c/d = 5)
Base
Horizontal
angle θ,
Cone depth
hyperboloid
semi
Vertical semi
degree
(h 1 ), inch
depth (h 2 ), inch
axis (c), inch
axes (d), inch
32
0.067
0.502
7.436
1.487
38
0.238
0.331
6.259
1.251
45
0.470
0.099
2.425
0.485
[0095] (c) Equal Catenoid
[0096] The development of the surface of the necking region was obtained by rotating a tangent line and a catenary curve 360° about the couplers longitudinal axis as shown in FIG. 10 . The catenary curve is characterized by its scaling parameter a and its vertex location. Unlike the elliptic torus and the hyperboloid, the catenoid has only one geometrical case for each base angle. The following set of equations is developed for the geometrical relationships of the necking region based on the geometrical constrains and the catenary curve characteristics.
[0097] Base angle is the slope of the tangent
[0000] m =tan θ (18)
[0098] Total depth of necking region is 0.57″
[0000] h 1 +h 2 =0.57″ (19)
[0099] Points B (x B , h 2 ) and D (0.812,0.57) satisfies the tangent equation
[0000] y D =m·x D +c (20)
[0000] y B =m·x B +c (21)
[0100] Points B (x B ,h 2 ) satisfies the elliptic torus equation
[0000]
x
B
=
a
·
Cosh
(
h
2
a
)
-
x
k
(
22
)
[0101] Vertex location at point A (0.291,0) requires that.
[0000] a=x k +0.291 (23)
[0102] Tangency condition at point B.
[0000]
Discriminant
of
x
-
a
·
[
1
+
1
2
!
(
m
·
x
+
c
a
)
2
]
+
x
k
=
0
(
24
)
[0103] The geometry of the necking region of the coupler was obtained by solving the aforementioned eight simultaneous equations (Eqns 18 to 24) to find the eight geometrical parameters (c,a,x B ,h 1 ,h 2 ,m,x k ). Table (7) shows the calculated geometrical parameters for some base angles while FIGS. 11( a )- 11 ( c ) shows the corresponding snapshots of the EF model.
[0000]
TABLE (7)
Geometrical parameters for necking region with catenoid.
Base angle θ,
Cone depth (h 1 ),
catenoid depth
Scaling parameter
degree
inch
(h 2 ), inch
(a), inch
32
0.081
0.488
0.305
38
0.244
0.325
0.254
45
0.472
0.098
0.098
[0104] (d) Unequal Elliptic Tori
[0105] This case is similar to case (a) except that there are two different lines and two different elliptic tori that are used to create the necking region. The development of the surface of the necking region in this case was obtained by rotating the two tangent lines and the two elliptic tori 360° about the couplers longitudinal axis as shown in FIG. 12 . The elliptic tori are characterized by their horizontal and vertical axes (a 1 , b 1 and a 2 , b 2 ) and their centers location at point C 1 (0.291+a 1 ,0) and point C 2 (0.291+a 1 ,0). One horizontal-to-vertical axes ratio (a/b) of 1.5 is examined in the optimization process. The same set of equations (Eqns 3-9) is used for developing the geometrical relationships of each half of the necking region based on the geometrical constrains and the elliptic tori characteristics. Three different base angles are altered to develop six cases of necking regions with unequal base angles as shown in the snapshots in FIG. 13( a )- 13 ( f ). The base angles are 45°, 42°, and 32°. The three selected angles represent large, moderate, and small angles and cover the entire range of base angles. The dimensions for the six cases are also summarized in Table (8).
[0000]
TABLE (8)
Geometrical parameters for necking region with unequal base angles.
Case 1
Case 2
Case 3
Case 4
Case 5
Case 6
First base angle
45
45
45
42
42
32
θ 1 , degree
Second base angle
45
42
32
42
32
32
θ 2 , degree
First cone depth
0.48
0.48
0.48
0.39
0.39
0.16
(h 1 ), inch
First elliptical
0.09
0.09
0.09
0.18
0.18
0.41
torus depth
(h 2 ), inch
Second cone
0.48
0.39
0.16
0.39
0.16
0.16
depth (h 1 ), inch
Second elliptical
0.09
0.18
0.41
0.18
0.41
0.41
torus depth (h 2 ),
inch
Horizontal axis
0.24
0.24
0.24
0.46
0.46
0.85
for first
elliptical torus
(a 1 ), inch
Horizontal axis
0.16
0.16
0.16
0.31
0.31
0.56
for second
elliptical torus
(a 2 ), inch
Vertical axis for
0.24
0.46
0.85
0.46
0.85
0.85
first elliptical
torus (b 1 ), inch
Vertical axis for
0.16
0.31
0.5
0.31
0.56
0.56
second elliptical
torus (b 2 ), inch
Objective Function
[0106] The main objective is to reduce or to minimize the stress gradient within the cone and the surface of revolution. In particular, the stress gradients through the necking region need to be reduced or minimized. Two cases are considered in this investigation as discussed herein; equal base angles and unequal base angles.
(a) Equal Base Angles
[0107] In this case it is assumed that the two base angles in the necking region are equal. This would yield symmetric necking region about X and Y axes as shown in FIG. 12 . In this case the stress gradients for the top and bottom halves are similar and therefore examining only one half of the necking region is sufficient. Therefore, the stress gradient between points A & B (SG_AB) and the stress gradient between points B & D (SG_BD) as shown in in FIG. 14 is minimized. To minimize the stress gradients, the objective function F were developed and evaluated as discussed in this section. The necking geometry has one independent variable which is the base angle (θ) and other dependent variables that fully describe the coupler geometry [(a, b, h 1 , h 2 ) for elliptic torus case; (c, d, h 1 , h 2 ) for hyperboloid case; (a, h 1 , h 2 ) for catenoid case]. In each iteration, the design variable (base angle) θ is assumed and the corresponding design parameters including the curvature constants, the depth of the cone h 1 , and half the depth of the surface of revolution h 2 are computed.
[0108] The stress gradients between points A & B (SG_AB) and points B & D (SG_BD) were calculated based on the gradient of Von Mises stress obtained by EF simulation as described by Eqn. (25) & Eqn. (26) respectively. The objective function “F” is defined as a multi-objective function combining the two functions ƒ 1 and f 2 from Eqn. (25) and Eqn. (26) respectively.
[0000]
f
1
=
SG_AB
=
von
Mises
(
A
)
-
von
Mises
(
B
)
h
2
(
25
)
f
2
=
SG_BD
=
von
Mises
(
B
)
-
von
Mises
(
D
)
h
1
(
26
)
[0000] The objective function “F” is formulated as a weighted sum of the two stress gradients as described by Eqn. (27).
[0000] F=w 1 ·ƒ 1 +w 2 ·ƒ 2 (27)
[0000] where w 1 is the weight of the stress gradient between A & B, w 2 is the weight of the stress gradient between B & D. In this study, w 1 and w 2 are chosen to be ⅔ and ⅓ respectively. The preference made for SG_AB over SG_BD because our prior observations of fatigue behavior of the couplers (Phase I and Phase II of this study) showed that failure usually occurs in the necking region (AB). The base angle(s) θ with the lowest objective function value represents optimal design(s).
(b) Unequal Base Angles
[0109] In this case, it is assumed that the two base angles differ which would result in different dimensions between the top and bottom halves. This in turn will differ the stress gradients between the two halves. Two elliptic tori and cones were used with unequal base angles to define the surface of revolution region as shown in FIG. 15 . As a result, two objective functions are developed for the two halves. Points A, B 1 , D 1 are used to calculate the stress gradients for the top half SG_AB 1 and SG_B 1 D 1 as shown in Eqns (28) and (29) respectively. On the other hand, points A, B 2 , D 2 are used to calculate the stress gradients for the bottom half SG_AB 2 and SG_B 2 D 2 as shown in Eqns (30) and (31) respectively. The objective functions F 1 and F 2 for the two halves are then calculated according to Eqns (32) and (33) respectively with same weights for stress gradients as used for the equal base angles case.
[0000]
f
AB
1
=
SG_AB
1
=
von
Mises
(
A
)
-
von
Mises
(
B
)
h
2
(
28
)
f
BD
1
=
SG_B
1
D
1
=
von
Mises
(
B
1
)
-
von
Mises
(
D
1
)
h
1
(
29
)
f
AB
2
=
SG_AB
2
=
von
Mises
(
A
)
-
von
Mises
(
B
2
)
h
4
(
30
)
f
BD
2
=
SG_B
2
D
2
=
von
Mises
(
B
2
)
-
von
Mises
(
D
2
)
h
2
(
31
)
F
1
=
w
1
·
f
AB
1
+
w
2
·
f
BD
1
(
32
)
F
2
=
w
1
·
f
AB
2
+
w
2
·
f
BD
2
(
33
)
Results and Analysis
[0110] The range of base angles θ was determined for each surface of revolution so that it achieves the geometrical considerations. Based on the geometrical consideration, the elliptic torus has a base angle ranging between 20° and 46° while the hyperboloid and catenoid has a base angle ranging between 30° and 46°. It is important to note that the current design for Alternative (AL-1) couplers is based on base angle of 45°.
[0111] The change in couplers dimensions as a function of base angle is depicted in FIG. 16 . One geometrical case for each surface of revolution is presented here. However, all other geometrical cases share similar results. For the elliptic torus, the case of a/b=1.0 is presented while for hyperboloid, the case of c/d=3.0 is presented. As expected, FIG. 16 , shows that all geometric parameters changes nonlinearly with the change of base angle θ. The surface of revolution depth h 2 increase nonlinearly with the increase of base angle θ while the cone depth h 1 decreases with the increase of base angle θ. The nonlinear relationship between the base angle θ and other dimensions demonstrates the complexity in the stress state and justifies the need for multi-objective optimization in order to determine a suitable or optimal coupler geometry for improved fatigue properties.
[0112] It is also observed in FIGS. 16( a )- 16 ( c ) that the change in base angle θ has a significant effect on the geometry of the coupler for relatively large base angles (>40°). As the base angle θ decreases, its effect on the coupler's geometry decreases gradually. For instance, in the snapshots for the case of elliptic torus shown in FIGS. 3-5 , there is no significant difference in geometry between couplers with base angles θ of 20°-30°. On the other hand, significant change in the coupler's geometry takes place as the base angles changes θ between 30° and 40°. A sensitivity analysis was performed to provide in-depth understanding of geometrical design sensitivity to the independent variable (base angle θ). The results of this sensitivity analysis are shown in FIGS. 17( a )- 17 ( c ) where the change in the dimensions with respect to the base angle θ (dimension gradient) is plotted against the base angle. The figure shows that at relatively high base angles (>40°) the change in dimensions is very sensitive to changes in the base angle. In design, it is recommended to have design geometry within a region of relatively low sensitivity in dimension gradient. This would reduce the statistical variation of the mechanical response of the coupler due to relatively small variations in geometry during production. The analysis performed here proves that the current design (AL-1) falls within a region of very high geometrical sensitivity which is not good.
[0113] Von Mises stresses at the two ends of the surfaces of revolution (points A & B) and the cone (points B & D) are presented in FIGS. 18( a )- 18 ( c ). It is noted that Von Mises stress at point A increases exponentially with the increase in base angle θ while Von Mises stress at point D remains constant. However, Von Mises stresses at point B is obviously more complex and increases in high order polynomial fashion with respect to the increase in base angle θ. The complexity in the Von Mises stress profile is due to the simultaneous change in the location of the point, the cross sectional area of the respected plane, and the curvature of the surface. The trend for Von Mises stress is similar for all surfaces of revolution or substantially independent of the surface of revolution used.
[0114] The stress gradients SG_AB and SG_BD are shown in FIGS. 19( a )- 19 ( c ). The figure also shows that above base angle 40°, SG_AB is very high and SG_BD is lower than its peak but still higher compared with much smaller angles such as 26° in the case of elliptic torus or 32° in the case of hyperboloid and catenoid. As the base angle decreases, SG_AB decreases significantly and SG_BD increases slightly. As both gradients govern fatigue behavior, it is obvious that current geometry with traditional high base angle θ=45° does not fall within an optimal design region/interval. Similar trends were observed for all surfaces of revolution.
[0115] There exists two objectives: reducing the two stress gradients A-B and B-D. It is obvious from FIGS. 19( a )- 19 ( c ), that these objectives are not necessarily antagonistic. One technique to handle this case is to combine both objectives in a single objective function based on Eqn. 20. The combined objective function is calculated and plotted as a function of the base angle θ as for all geometrical cases shown in FIGS. 20( a )- 20 ( c ). Two regions for the combined objective function can be identified in FIG. 20 . The first region is for large base angles (θ>40°) where the current design (θ=45°) exists. In this region, the combined objective function is very high and the design is therefore not a suitable one. The second region falls for small base angles (θ<40°). In this region, the combined objective function decreases significantly and approaches steady state or constant value between θ=30° and θ=37°. The objective function of the current design is 120 ksi/inch, approximately three times the steady-state value (˜40 ksi/inch). This is because the base angle θ for the current or traditional design is relatively large (>40°) compared with the preferred design region θ=[30″-37°] in accordance with the invention. It is also important to note that the objective function is insensitive to the type of surface or revolution used in the optimization. In other words, all surfaces of revolution share similar trend for the objective function and very close stress gradient values.
[0116] The effect of unequal base angles on the stress gradients and objective functions is evident in Table (9). The table shows two objective functions for each case, one objective function for each half of the necking region. It is important to consider the maximum objective function for each case since it represents the critical stress gradient upon which the fatigue failure occurs. In this context, the table shows that the highest maximum objective function of 203 ksi/inch belongs to case 1 (θ 1 =θ 2 =45° while the lowest maximum object function of 44 ksi/inch belongs to case 6 (θ 1 =θ 2 =32°). The cases 2 to 5 vary in their maximum objective function between case 1 and case 6. For instance, case 3 (θ 1 =45°, θ 2 =32° exhibits maximum objective function of 89 ksi/inch. It is evident from these results that in order to reduce the maximum objective function, the two base angles should lie within the optimal range (θ=30-37°). It is also evident that the two base angles do not have to be equal to achieve suitable or optimal performance as long as they both lie within the optimal range.
[0000]
TABLE (9)
Objective function for necking region with unequal base angles.
Case 1
Case 2
Case 3
Case 4
Case 5
Case 6
First base angle
45
45
45
42
42
32
θ 1 , degree
Second base angle
45
42
32
42
32
32
θ 2 , degree
First objective
146
110
89
60
52
41
function (F 1 ),
ksi/inch
Second objective
203
115
55
100
48
44
function (F 1 ),
ksi/inch
Maximum
203
115
89
100
52
44
objective
function (F 1 ),
ksi/inch
[0117] The design process was performed using three types of surface of revolution (elliptic torus, hyperboloid, and catenoid) and a wide range of base angles. The representative surfaces of revolutions cover all possible surfaces given the coupler geometry. The base angle of the coupler denoted “θ” was defined as the independent design variable. The relationships with other geometrical dependent variables were developed. A set of constraints for acceptable design of the coupler was defined. A combined multi-objective function to reduce the stress gradients in the surface of revolution and the cone areas was defined. The effect of unequal base angles on the stress gradient was also investigated.
[0118] The design showed that the objective function is substantially insensitive to the type of surface of revolution. The optimization also showed that the objective function is sensitive to the base angle θ. A base angle range between 30 to 37° represents a good working range for minimizing the objective function and improving the fatigue strength of the coupler. Within this interval or range the stress gradients are less than ⅓ of stress gradients developed with the current (Existing) or alternative (ALT-1) design angle of θ=45°. In addition, it is evident that preferred fatigue performance can be obtained using unequal base angles as long as both angles are within the optimal range. The current designs, known as Existing or Alternative couplers, are obviously not a design that addresses and improves fatigue performance.
[0119] Breakaway couplers in accordance with the present invention include base angles and geometry within the range of 30°-37° (an angle of 32 degree might be considered). The new coupler design will have improved fatigue strength compared with Existing and Alternative (AL-1) couplers and have been referred to as “Enhanced-Fatigue” or “EF” Coupler. The “EF” coupler is designed to meet AASHTO requirements for highway couplers.
Test Results
Scope of Testing
[0120] The EF couplers were tested with the objective to evaluate the fatigue strength of the EF coupler and compare it with the Existing and Alternative couplers. Twenty couplers were tested under cyclic loading with different mean stress levels and different stress ranges and determining the number of cycles to failure. The equivalent Stress-Number of Cycles to failure (S-N) curves and report the types of fracture were observed. Moreover, two additional modified-optimized steel couplers were tested: EF-Mod-A and EF-Mod-B, shown in FIGS. 21( f )-( i ).
[0121] Four couplers of each type were tested under cyclic loading then the fatigue life was compared with Existing, Alternative, and EF couplers.
[0122] Referring to FIGS. 21( d ) and 21 ( e ) an enhanced fatigue or EF coupler in accordance with the present invention is shown which is provided with two full truncated cones at the two axial ends of the neck down region each having a base angle of 32°. Modified EF couplers, Mod-A and Mod-B are shown in FIGS. 21( f )-( i ) which have dimensions of the neck down region reduced from those in the EF coupler shown in FIGS. 21( d )-( e ). Thus, whereas the height of the neck down region for the EF coupler shown in FIGS. 21( d )-( e ) is 1.145″ and the minimum neck diameter is 0.582″ the height of the neck down region for EF Mod-A is 0.975″ and the minimum diameter is 0.57″. While the base angle θ of the upper cone is still 32° the lower cone has been further truncated somewhat to shorten the height of the neck down region and, essentially, remove some of the volume of material in the neck. Similarly, in FIGS. 21( h )-( i ) the aforementioned dimensions have been modified to provide a minimum neck diameter of 0.58″ and a neck height of 0.985″. The remaining dimensions of the externally and internally threaded ends or posts are the same for all of the couplers. The truncation of the lower cones for Mod-A and Mod-B were intended to change the amount of energy needed to sever the coupler upon impact. However, the upper cone base angles for all of these couplers in FIGS. 21( d )-( i ) are all the same at 32°
Fatigue Tests Description
[0123] The purpose of the fatigue test is to determine the number of cycles to failure and develop equivalent Stress-Number of Cycles to failure (S-N) curves to allow comparison of the fatigue behavior of the three types of galvanized steel couplers. The word “equivalent” here is used to describe the S-N curves as establishing the “true” S-N curves for the couplers requires testing very high number of specimens (>30 specimens). The “EF” coupler is examined under cyclic loading. The modified-EF, EF-Mod-A, and EF-Mod-B couplers are shown in FIGS. 21( a )- 21 ( c ). The fatigue test was performed with an Instron® loading frame connected to MTS® 793 Flex DAQ. The test was conducted on series of maximum 5 couplers at a time connected by the male and female threads to form a chain as in FIG. 22 . The chain is connected to the bottom platen with threaded rod and to the top cross head with plate bending frame. The frame is designed to avoid producing bending moments on the couplers.
Tension Fatigue Tests
[0124] Four test protocols were performed on a total of 25 specimens of EF couplers. Each test protocol was cyclic load controlled with a frequency of 1 Hz. The mean tension loads and stresses vary in the four test protocols as follows:
[0000] Test protocol-1 mean tension load of 4.85 kip, amplitude of 3.03 kip mean stress of 17.98 ksi, 51.59% of max stress test Test protocol-2 mean tension load of 6.37 kip, amplitude of 4.55 kip mean stress of 23.60 ksi, 67.72% of max stress test Test protocol-3 mean tension load of 7.88 kip, amplitude of 6.06 kip mean stress of 29.22 ksi. 83.85% of max stress test Test protocol-4 mean tension load of 9.40 kip, amplitude of 7.58 kip mean stress of 34.85 ksi, 100% of max stress test
Furthermore, 8 specimens of the modified-EF couplers, EF-Mod-A and EF-Mod-B, were tested under Test protocol-4.
[0125] The couplers were kept under tension-tension fatigue cycles during all test protocols 1 through 4. All stress values reported represent the average stress over the area of the smallest diameter of the coupler as shown in FIG. 23 . It is important to note that the smallest diameter of the couplers were kept the same for all couplers compared here (Existing, Alternative and EF). The mean loads and load amplitudes for each test protocol are shown in FIG. 24 . The equivalent fatigue stress cycles for the four protocols is shown in FIG. 25 . If failure did not happen, the test was stopped at 1.7 million cycles for test protocol-1 and at 1 million cycles for all other test protocols. All modified-optimized couplers were tested under Test protocol-4 only.
Fatigue Test Results
[0126] All couplers tested under test protocol-1 and test protocol-2 did not fail. All the couplers failed in test protocol-3 and test protocol-4 fractured at the threads section and not at the coupler's neck. This indicates that the coupler's neck does not govern fatigue of the couplers any further. This proves the significantly different performance of the EF couplers compared with Existing and Alternative couplers where neck failure was dominant in fatigue. FIG. 5 shows photos of the five fractured couplers under maximum fatigue stress (Test Protocol-4). For modified-EF couplers, EF-Mod-A and EF-Mod-B, four couplers of each type were only tested under test protocol-4. FIG. 6 and FIG. 7 show tested EF-Mod-A and EF-Mod-B couplers.
[0127] The object of the design effort was to experimentally compare the fatigue strength/life of EF couplers with both Existing and Alternative couplers. Twenty EF Transpo couplers were tested under 4 testing protocols to identify the fatigue strength of the couplers. These protocols included varying mean stress values.
[0128] All the tests showed that the fatigue strength of the EF Transpo coupler is higher (twice to six times) than that of the Alternative couplers under tension fatigue loads. All tested couplers did not fail under mean stresses of 17.98 ksi and achieved endurance limit of 1.7 million cycles. Fracture surfaces of EF couplers were recorded and no failure took place at the coupler's neck. Failures in the outer thread were observed at much high fatigue strength compared with Existing or Alternative Couples. It is evident that the EF coupler has superior fatigue strength compared with Existing and Alternative Transpo couplers.
[0129] Furthermore, it is also evident that the modified-EF couplers, (Mod-A) and (Mod-B), have superior fatigue performance that is one order of magnitude higher in fatigue life than Existing couplers and about 4 times higher in fatigue life compared with Alternative couplers. Some of the modified-EF couplers did not fail under the test protocol #4 used. The modified-EF couplers showed a fatigue life about 75% of that of the EF couplers. Nevertheless, the fatigue life shown by the modified-EF is superior for all intended applications and is an order of magnitude higher than Existing couplers used today in field applications.
[0130] 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. | A break-away coupling is formed of metal and has a central axis and a necked-down central region formed by two inverted truncated cones each having larger and smaller bases. The cones are joined at the smaller bases by a narrowed transition region having an exterior surface formed by a curved surface of revolution having an inflection point of minimum diameter substantially midway of the coupling along the axis. The cones each define an angle θ 1 and θ 2 , respectively, at each of the larger bases, wherein both θ 1 and θ 2 are selected to be within the range of 20°-40° and, preferably within the range of 30°-37°. | 4 |
This is a continuation in part application of application Ser. No. 08/498,252, filed Jun. 29, 1996 now abandoned.
TECHNICAL FIELD
This invention is in the general field of an on-site glass receptacle hammer mill to facilitate the environmentally safe disposal and recycling of primarily glass beer, soda, wine, condiment and food receptacles in bars, restaurants and other establishments generating substantial glass waste in the course of their business or operations. This would also include but not be limited to larger, industrial sized glass receptacle hammer mill and/or glass crushers.
BACKGROUND OF THE INVENTION
Glass receptacles, be they containers for beer, wine, soda, food or condiments, are a problem for the business and/or establishment generating the empties as well as posing as a landfill waste disposal problem when they are dumped as trash and left to nature to assimilate them back into the earth. Unbroken glass receptacles also consume considerable amount of space, critical waste disposal area space that is becoming dangerously scarce throughout the globe. The decomposition of discarded glass receptacles can take centuries.
Most, if not all glass receptacles, can be recycled and reused in the furtherance and manufacture of new glass receptacles. This would save valuable landfill waste disposal space; reduce finite mineral consumption; plus conserve the amount of energy required in recycling glass receptacles rather than manufacturing the receptacles from raw materials.
A problem arises when conservation-minded individuals and businesses attempt to save and store empty glass receptacles for recycling. The space required for the storage of empty glass receptacles can be considerable, especially in small or enclosed areas such as in bars and restaurants. Transporting these glass containers can also be a problem when the empty glass containers are in their original, unbroken form. Breaking glass containers immediately after use can produce health and safety hazards especially if the breaking is conducted in the beverage, food or condiment serving area. Additionally, the box or container in which the glass receptacles were originally packaged, would not nor could not adequately catch, contain or allow transportation of broken glass chard cullets. This invention addresses the problem of broken glass, including glass dust, so that it's adequately handled to virtually eliminate contamination of the ambient air in the working environment. This is done by means of a dedicated collection bag that can be adequately sealed when transported from the breaking area to the recycling storage area. Empty glass receptacles can be generated in large quantities in a minimum amount of time in even a relatively small establishment. Previous inventions showed various means of crushing or breaking a single bottle at a time and usually didn't provide for the entire process to be encapsulated and/or self-contained from glass receptacle insertion through removal and storage of glass chard cullets for recycling service pickup.
An establishment that is in the food service business with glass receptacles as merely by-products of that service, i.e. bar or restaurant, normally doesn't have the time or means to adequately preserve and store the empty glass containers in the area and usually throw them into the common trash containers to be picked up and delivered to the nearest land fill disposal area.
Previous inventions and all the prior art in this field attempt to address some of the listed problems but most, if not all, do not answer or provide for all of the problems associated with preparing empty glass receptacles for collection, storage and recycling in an effective, economical and safe manner. The patents reviewed: U.S. Pat Nos. 5,350,120; 5,328,106; 5,310,122; 5,289,980; 5,226,606; 5,242,126; 5,215,265; 5,186,403; 5,184,781; and 5,150,844 bear this out.
Thus, this invention addresses all of the above listed problems of trash accumulation, storage and disposal and the opportunities for conservation, energy savings and recycling of a by-product. This invention apparatus and methodology adequately solves the problems addressed above and makes on-site glass receptacle crushing economically feasible, environmentally and occupational safe, plus prepares recyclable glass chard cullets for easy storage, transportation and recycling.
SUMMARY OF THE INVENTION
Described herein is an apparatus and method for smashing empty glass receptacles into pre-determined sizes to facilitate the collection, storage, transportation and recycling of glass chard and/or cullets. This apparatus is a type of hammer mill that, when the glass receptacles are dropped or inserted into the area of the motor driven radius of the horizontally spinning, hardened blades, encountering the blades, and are thereby shattered into pre-determined chard or cullet size. The embodiment of the apparatus described herein includes a cabinet or housing that is comprised of two sections. The upper section has two compartments, a rear compartment that contains the motors, gears and electrical wiring. The upper front compartment has a hinged lid that can be opened to expose a loading trough that would accept a substantial quantity of empty glass receptacles. The lower section is sealed from the upper section by means of a partition that contains a rotary tray door that remains in the closed position until the upper lid has been closed and the safety circuit activated and the hammer mill blades have reached optimum revolution speed. Once the operator has filled the upper trough with the glass receptacles that are to be smashed, a start switch will activate the motor and accelerate the hammer mill blades in a horizontal plane to the pre-determined optimum revolution speed to produce the pre-determined correct size broken glass chard and/or cullets, a rotary or horizontally slideable tray door located in the partition between the upper and lower chambers whereby the rotary tray door is attached to and moved by a motor activated gear drive that turns a pinion attached to the rotary tray door so that the rotary tray door opens or a horizontally located slideable tray door mounted on dual tracks and moved horizontal by means of a pinion motor driving a gear that would then open allowing the glass receptacles to drop into the hammer mill blades. A pinion motor turning a pinion attached to a rotary try door turns the center mounted pinion and turns the rotary tray door through a 360 degree movement thus allowing the glass containers to fall through from the upper loading chamber into the hammer mill break area. The horizontally located, slideable tray door is attached to a pinion motor and pinion gear that drive the slideable tray door back and forth on dual racks. The rotary tray door does not require any reversing motor as it is driven through a 360 degree horizontal plane. The slideable tray door utilizes relay switches that are appropriately mounted to automatically reverse the pinion motor when the slideable tray door reaches its fully opened position and another relay switch is mounted to shut the pinion motor off when the slideable tray door is fully closed and ready for another load of glass bottles.
That upper rear chamber portion, that chamber that does not house the glass receptacle loading trough, is separated by means of a sealing partition. The portion of the upper chamber that is not dedicated as the glass bottle loading trough contains a motor, an electric motor in the preferred embodiment, that is situated in one corner of the cabinet. The motor would be located such that a sheave would be mounted on the bottom or lower end of the motor and would be above and nearest the top of the upper and lower chamber partition. A drive chain or rubber belt would then extend from the motor sheave transversely to the center of the cabinet where it would be matched to a sheave mounted to a drive shaft that extends vertically through the upper and lower chamber partition. The drive shaft would be mounted on flange and pillow block bearings so that the hammer mill blades mounted on the lower end of the vertically mounted shaft would allow the hammer mill blades to rotate horizontally just under the partition of the upper and lower chambers. The mounting of the motor in one corner and transferring the rotary power to the vertical shaft mounted in the center of and through the partition of the upper and lower chambers of the cabinet by means of a chain or belt drive would enable the upper glass receptacle loading trough to be maximized in size loading as many empty glass receptacles as possible.
The rotary hammer mill blades are attached by means of the vertical drive shaft at the under side of the upper and lower chamber partition just below the slideable tray door. The activation of the motor by the operator would, in addition to starting the motor driven hammer mill blades' rotary motion in a horizontal plane, would also activate the rack and pinion drive gear (if it is desirable to have the slideable tray door to be independently motor and gear driven), and open the slideable tray door allowing the glass receptacles to drop from the upper loading trough down into the spinning hammer mill blades thus smashing the glass receptacles into the predetermined size desired.
If the apparatus does not employ the motor/gear rack and pinion drive system, a manual slideable tray door mechanism is also shown whereby the operator can manually open the slideable tray door to allow the glass receptacle to fall into the rotating hammer mill blades after the upper trough lid has been closed, the circuit switch closed and the motor driven hammer mill blades reach or are at optimum revolutions per minute as determined by the cullet size desired by the recycling industry. The slideable tray door would be located adjacent to the front of the cabinet and extend in two quarter pie shapes nearer to but not entirely reaching the midpoint of the upper and lower chamber partition where the vertical drive shaft is located. Opening the slideable tray door would expose the hammer mill blades below an elliptical-shaped aperture allowing the glass receptacles to drop through and into the hammer mill blades thus shattering into predetermined shards and/or cullets.
The blades are surrounded or girdled by a tapered metal skirt to ensure that the hammer mill blades contact with the glass receptacle and the shattered, flying glass cullets can not be flung uncontrollably throughout the lower chamber but are directed so they drop into the cullet collection container bag.
The lower chamber also holds the glass chard or cullet collection container cradle frame. The collection container cradle frame can be made of sheet metal or plastic or any other such material so as to allow the actual bag or chard collection container to be held in place until the collection container is full and requires removal and replacing. The container cradle frame is bottomless. It is best manufactured to include tapered upper flanges that will hold the actual collection bag in place while it is being filled.
To remove the cullet filled bag from the lower chamber, the collection container cradle frame can be pulled from the lower chamber by means of an attached handle.
This described apparatus and methodology can be of any size to enable operators to use in an industrial application but the herein described type apparatus would fit in a bar, restaurant or similar type establishment.
Another configuration of the apparatus would be to have a spherical door that pivots around a center tube that houses the drive shaft and two flange bearings. The center tube would be sealed by multiple sealing points, the flange bearings and several layers of sealing compounds.
The electrical drive motor would be mounted so that the drive pulleys would be on top of the motor drive shaft and the hammer mill blades shaft.
Instead of a pinion motor activating and pulling and pushing the loading bin door open and shut, the center mounted, spherical door would be activated by a DC drive motor and rotate around the center tube so that the loading bin door is opened and shut by a complete revolution of the spherical loading bin door.
In another embodiment of the present invention, there is provided an apparatus for crushing glass that uses hammer mill blades that control the movement of a door for accessing the hammer mill blades. As shown previously, the base of the apparatus can have wheels to make it easier to move the apparatus. The apparatus has a housing halving an upper chamber and a lower chamber being separated by a partition, a top and a base The upper chamber is divided into a forward section and a rearward section by a wall. The rearward section is sealed from the forward section and the lower chamber by the wall and the partition. The forward section defines an opening therein that is positioned adjacent to the top of the housing. The partition defines a hole therein that is substantially the same size as the opening defined by the forward section
A motor means is mounted within the rearward section having a pulley shaft connected to a hammer mill blade shaft having a first end and a second end. The first end extends into the lower chamber. A first hammer mill blade and a second hammer mill blade are attached to the first end of the hammer mill blade shaft.
A hinged lid is attached to and in covering relationship with the opening defined by the forward section. A funnel means has mouth portion and a neck portion. The mouth portion is connected to the partition and the neck portion is connected to a receiving means. The funnel means receives the crushed glass cullets and funnels them towards the receiving means.
There is a rotatable panel that defines a hole therein sized to fit the hole formed by the partition so that more than one glass container may be deposited into the apparatus at one time. The rotatable panel is attached to a rotatable panel shaft. The panel remains in a closed position so that no glass enters the lower chamber when the apparatus in turned off or not activated. Once glass is placed in the forward section and the lid is closed, the hammer mill blades are activated and the rotatable panel shaft moves the rotatable panel to an open position so the glass contacts the moving hammer mill blades. There is a weighing means disposed in the base of the housing and a means for cleaning the forward section, the lower chamber, and the hammer mill blades.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is the external appearance of the apparatus in a perspective view that embodies the preferred general principals of this invention.
FIG. 2 is a left side cutaway view of FIG. 1 partially in section and illustrating functional elements of this invention that encompass a preferred configuration.
FIG. 3 is a perspective view of the cullet bag cradle frame detailing the preferred configuration.
FIG. 4 is a cutaway perspective view of the upper chamber of FIG. 2 embodying a preferred general principal of this inventions configuration and the placement of relay switches, relays and relay contact blocks to energize and stop the pinion motor.
FIG. 5 is a detailed view of the movable shelf utilizing either a foldable, manual push/pull handle or a linear drive motor and worm gear detailing the preferred configuration.
FIG. 6 is a detailed view as shown in FIG. 2 detailing the preferred configuration with some of the preferred alternative configurations detailing a rack and pinion drive mounted on the slideable tray door.
FIG. 7 is a detailed view of the apparatus utilizing a front loading door that can be protracted and retracted with the preferred configuration.
FIG. 8 is a perspective view of FIG. 2 incorporating additional preferred configurations including the placement of sound proofing materials.
FIG. 9 is a view along cut lines A--A showing the layout of the rack and pinion attachment on the slideable tray door and a proposed arrangement of the pinion motor, pinion drive shaft, gears and matching racks.
FIG. 10 is a cutaway perspective view of the apparatus embodying a preferred general principal of this inventions configuration and the placement of detailed components.
FIG. 11 is a detailed view of the motors and gear drive arrangements that drive the pinion shaft attached to the hammer mill blades and the required bearings and packing sealing.
FIG. 12 is a detailed view of the mounting bracket, motors, sheaves and belt drives.
FIG. 13 is a sectional view of the apparatus, loading bin, rotary door, hammer mill blades and glass container break area.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In detail and in which like numerals refer to like parts throughout, FIG. 1 depicts the external appearance of an apparatus that embodies principals of the present invention in a preferred form. The apparatus 1 is seen to be substantially a sealed rectangular box like device with the top encompassing a hinged portion 3 that allows the lid sections 2 to be affixed to apparatus 1 and allow lid section 4 to be opened. Momentary activation switch 5 is shown in the preferred position. Lower section of apparatus 1 shows door 7 latched when closed by latch 6. The apparatus 1 is mounted with omni-directional wheels or rollers 8 to allow apparatus 1 to be easily moved.
FIG. 2, shows the top of apparatus 1 containing hinge 3 to allow the front lid 4 to be opened 9 to expose collection area 11 for glass bottles for crushing. The apparatus contains an inner mechanical locking device 10 to lock lid 4 closed whenever motor 13 has been activated by pressing momentary switch 5. The mechanical locking device 10 also disables lower compartment 44 from being opened when the motor 13 has been engaged, the hammer mill double blades 17 in motion and the loading bin movable closure door 22 is aperture and/or opened.
The apparatus 1 is divided into an upper chamber 39 and a lower chamber 40 being separated by a partition shelf 19. The upper chamber 39 is also divided and sealed into a forward chamber 11 and a rearward chamber 44 by means of partition 19. Forward Chamber 11 is the glass bottle loading area and is lined with stainless steel sheeting for anti-corrosion and contamination and rearward chamber 44 is the motor, drive shaft, jack shaft, pillow block bearings, motor mounting bracket, interior circuit breaker and ancillary equipment housing area. Forward chamber 11 and rearward chamber 44 are sealed from each other as best as can be with sealing compound.
Motor 13 is mounted against the wall nearest one corner of rearward chamber 44 by means of motor housing bracket 12. Rotary drive shaft 16 has pulley 14 attached. Drive belt 15 drives jack shaft 45 pulley 53 which drives hammer mill blades 17 pulley 46 which is mounted on hammer mill blade rotary drive shaft 47. Drive belt 52 connects jack shaft 45 pulley to hammer mill rotary shaft pulley 53. Rotary drive shaft 16 is mounted between one pillow block bearing 43 and one flange bearing 34. Jack shaft 45 is also mounted between a pillow block bearing 48 and a flange bearing 49. The hammer mill blade rotary drive shaft is also mounted between pillow block bearing 50 and flange bearing 51.
Motor 13 is preferably at least a 1/2 horsepower 110/120 v electric motor that is electrically connected through circuit breaker box 33 that encompasses a 20 amp breaker. Circuit breaker box 33 is attached by means of electrical cord 32 to any available 110/120 v outlet through electrical junction box 31.
The hammer mill blade rotary drive shaft 47 has two heat-treated, alloy steel, case hardened, hammer mill blades 17 and 25 perpendicular to the hammer mill drive shaft 47 but mounted horizontally so that they meet at the center of the hammer mill blade drive shaft 47 and cross each other at 90° with spacer 55 providing a 1 inch space between the first hammer mill blade 17 and the second hammer mill blade 25. The second hammer mill blade 25 is the lower and longer and than the first hammer mill blade 17. The second hammer mill blade 25 is the lower positioned blade that is approximately four inches longer than the first hammer mill blade 17.
The hammer mill rotary drive shaft 47 is mounted through the upper chamber 39 and lower chamber 40 partition shelf 19 and sealed by means of upper hammer mill rotary drive shaft flange bearing 51 and lower hammer mill rotary drive shaft flange bearing 54. Upper chamber 11 and the adjacent partition shelf 19 has a matching corresponding space similar to a half moon shape in the area forward of chamber 39 and chamber 11 partition 19. Hammer mill blades 17 and 25 are positioned beneath partition 19 by means of a fixed spacer 18 that is permanently affixed to hammer mill rotary drive shaft 47 to ensure the glass bottles would not encounter the hammer mill blades 17 and 25 until they fell into the cullet collection area 24 below partition 19 and inside the funnel shaped hammer mill blade/bottle impact area 23. The inside of the funnel shaped hammer mill blade/bottle impact area 23 is also sheeted with stainless steel.
The upper chamber 11 also called the loading bin has a movable (slideable) tray bottom 22. Bottom 22 cannot move until mechanical locking device 10 has been engaged and momentary switch 5 activated. Bottom 22 is mounted between two geared racks 56 that are attached on opposing sides of chambers 11 and 39 that is driven by pinion gear 57 that is activated by pinion drive motor 58.
When the loading bin area door 4 is opened to load bottles for crushing, the system has closed movable slide door 22. Once the loading bin door 4 has been closed and the mechanical locking device 10 engaged, an operator can push momentary switch 5 to start motor 13 thus engaging the drive belts 15, 59, 60 developing a pre-determined RPM for the hammer mill blades 17 and 25. When a pre-determined RPM of the hammer mill blades has been reached, then a electrical lockout device 61 disengages the rack and pinion drive motor 58 engaging the fixed geared racks 56, that is permanently attached to movable shelf 22, with pinion 57. The electrical lockout device 61 and the mechanical lockout device 10 both ensure that the process could not be interrupted nor upper chamber door 4 or lower chamber door 7 be opened until the cycle was completed. The cycle would include the dual locking of the mechanical lock 10 and the electrical lockout device 61, the activation of motor 13 developing a pre-determined RPM for hammer mill blades 17 and 25 and then engaging pinion drive motor 58 turning pinion 57 that engage geared racks 56 thus aperture movable tray door 22 laterally from chamber 11 into chamber 39 allowing the glass bottles previously loaded in chamber 11 to drop through the aperture 62 into the funnel shaped hammer mill blade/bottle impact area 23 encountering the hammer mill blades 17 and 25 thus breaking into cullets of a pre-determined size and dropping them into a gusseted, disposable bag 63 that is supported by cullet storage box 29 for recovery and recycling.
The bottom of chamber 40 has weight sensors 27 mounted thereon to determine when the cullet collection bag 63 has received a pre-determined weighted accumulation of cullets and electronically transmits a warning signal that activates loaded condition light 65.
FIG. 2 also shows the bottom chamber 40 can be opened by door 7 when the mechanical locking device 5 and the electrical lockout device 61 are not engaged by aperture latch 6 thus allowing cullet storage box 29 to be removed and the gusseted, disposable bag 63 full of cullets to be removed when cullet storage box 29 has been lifted and the hinged bottom 66 drops open. Noise suppression foam and/or other type noise suppression material 67 to be inserted into or placed about all open chambers not affecting any moving parts.
FIG. 3 is a detailed view that shows the cullet storage box 29 is manufactured of a material that will maintain rigidity of shape and size so as to adequately hold gusseted, disposable bag 63 to hold the cullets. The bottom of cullet storage box 29 is hinged by hinges 26 so as to allow the bottom to drop open when the cutlet storage box 29 is lifted vertically. The hinged bottom 66 allows support for gusseted, disposable bag 63 when in the lower chamber 40 and drops open to allow the gusseted, disposable bag 63 full of cullets to remain in place on the floor when the cullet storage box 29 is lifted to remove the disposal bag 63 of cullets.
FIG. 4 is a perspective view that shows the arrangement inside cabinet 1 of the motor drive and shaft assembly area 44 the drive motor 13, jack shaft 45 hammer mill blade pulley 46 upper hammer mill blade 25, lower hammer mill blade 17 geared rack 56 movable slideable tray door slot 37 jack shaft bearing 49, jack shaft pulley 53, jack shaft pillow block bearing 48, alternate manual push/pull moveable shelf handle 35, motor drive belt 15 drive belt jack shaft to hammer mill blade shaft 59. The slideable tray door 69 has a relay shim block 86 mounted so that it makes contact with relay contact shim block 86 and activates relay switch 85 so that when the activation switch 5 is energized, relay switch 85 allows pinion drive motor 58 to move the slideable tray door 69 along geared racks 56 opening the aperture to allow the glass bottles to fall through and into the hammer mill blades 17 and 18. The slideable tray door 69 makes contact with relay switch 85 when the slideable tray door reaches the end of the geared racks 56 and the relay switch 85 reverses the pinion drive motor 58 so that the slideable tray door 69 returns to the closed position.
FIG. 5 shows a detailed view of the moveable (slideable) tray 69 and the access slot 37 for hammer mill blade rotary drive shaft 47 clearance plus both a manual push/pull folding arm 35 and an alternate linear drive worm gear 21 utilizing a linear drive motor 20.
FIG. 6 shows a detailed view of the moveable (slideable) tray 69 and the access slot 37 for hammer mill blade rotary drive shaft 47 clearance and a rack 56 and pinion 57 driven by pinion drive motor 58.
FIG. 7 shows a detailed view of the apparatus utilizing a front bottle loading bin 11 that would enable a user to load bottles while the apparatus is position under a counter. The activation switch 5, dual locking device 10, the electrical lockout safety device 61 and the cutlet bag load condition warning light 65 would be moved to the side of the apparatus to facilitate the front loading bin 11.
FIG. 8 shows the preferred application of sound proofing materials 60 in the upper chamber 39 of the apparatus.
FIG. A--A is a detailed cut view of FIG. 2 showing the slideable tray door 69 with the mounting of the relay contact blocks 84, the relay switches 85 and the relay shim blocks 86, the geared racks 56, the pinion drive shaft 72 and the pinion gears 57 in apparatus cabinet 1. Also shown is the hammer mill blade rotary drive shaft 47 clearance slot 37.
OPERATION
This apparatus is designed to be placed in establishments that generate considerable and substantial amounts of empty glass bottles ranging from beer bottles to wine jugs. The invention is designed so that up to a case of empty beer bottles or several wine jugs can be placed within the upper loading chamber 11, the lid 4 closed and automatically locked and an operator then initiates the glass bottle crushing process by pushing a momentary switch 5. The process starts with the pressing of the momentary switch 5 which activates the electrical lockout devise 61 and starts the electric motor 13 thus rotating the drive 16, jack shaft 45 and hammer blade drive shaft 47 to a pre-determined speed after which reaching, enables the pinion drive motor 58 causing the pinion 57 to engage the geared rack 56 that is permanently attached to a slideable tray door 22 that is pulled rearward from the upper loading chamber 11 towards and into the equipment chamber 39 thus exposing the contents (bottles) of the loading chamber 11 to an aperture in upper and lower chamber partition shelf 19 that allows the contents (bottles) to come into contact with the hammer mill blades 17 and 25 while they are at fill pre-determined RPM speed. The use of contact relay switches 85 and the mounting of the relay shim blocks 86 so that contact with the relay contact blocks 84 enable the apparatus to be operated with a single push on the activation switch 5 and the cycle starts up and completes without any other procedures.
The contact of the contents (bottles) with the hammer mill blades 17 and 25 pulverizes the glass into a pre-determined size called cullets. The speed of the hammer mill blades 17 and 25 is critical and the configuration of the funnel shaped hammer mill blade/bottle impact area 23 to ensure the proper sizing of the cullets. The pulverized cullets then fall into a gusseted, disposable bag 63 that is held in place and supported by cullet storage box 29. The gusseted, disposable bag 63, when filled, can then be removed to the recyclable pickup area for delivery to a glass company for recycling. If the glass cullets aren't recycled, the pulverized cullets won't take up but a fraction of intact bottles in landfills.
This invention allows the originator of large amounts of empty glass bottles to economically pulverize the glass containers thus requiring substantially less storage area for the refuge discharge until the cullets are either recycled or shipped as small fragments to landfills. The size of the apparatus allows for placement in nearly every eating and drinking establishment to maximize the efforts of most such establishments to engage in as much recycling and environmentally safe trash disposal as possible.
Another embodiment of the present invention is shown in FIGS. 10-13. FIG. 10 is a cutaway perspective view of the apparatus 100 embodying a preferred general principal of this invention's configuration and the general placement of detailed components. The apparatus 100 is seen to be substantially a sealed rectangular box like device with the top encompassing a hinged portion 400 that allows the lid sections 202 and 300 to be affixed to apparatus 100 and allow lid section 300 to be opened. The forward section or loading bin area 500 is partitioned from the rearward section or equipment area 230 by wall 362. The entire loading bin area 500 is a sealed chamber on the four adjacent and opposed sides and allows rotary door 600 to be moved on a horizontal plane in a 360 degree rotary movement to allow glass containers loaded in the loading bin 500 to drop into the bottle break area 240 and be struck by the hammer mill blades 700 and 720. The broken glass cullets 110 drop through the funnel means 800 into the collection box 110 located in collection chamber 90. Weight means 140 ensures that a pre-determined amount of glass cullets 110 do not exceed a weight that would make removal difficult. Door 130 allows the apparatus 100 to be opened so the glass cullets 110 can be removed. Cleaning jet nozzle 380 is attached to a line or conduit 390 that allows cleaning fluid to be fed from intake valve 420. The wall 362 divides the loading bin 500 from the equipment area 230 in which bracket 280 holds motor 210 and motor 220. Motor 210 has motor shaft 310 on which sheave 200 is mounted. Belt drive 190 connects motor 210 to hammer mill blade shaft 350. Hammer mill blade shaft 350 has hammer mill blades 700 & 720 attached and held in place by lock nut 290. Hammer mill blade shaft 350 is located and sealed into tube 170 to ensure glass dust and cullets 110 cannot be introduced into equipment area 230. The hammer mill blade shaft 350 is sealed at both ends with packing material 320 and 330 and a polyflex seal 172. Non functional areas 410 and 120 are filled with noise suppression packing foam.
Rotary door motor 220 with a first sprocket 250 utilizing chain drive 270 attached to a second sprocket 260 that activates door 600 when apparatus 100 is activated in the run mode. The apparatus 100 is mounted with omni-directional wheels or rollers 150 to allow apparatus 100 to be easily moved.
In another embodiment of the present invention, there is provided an apparatus 100 for crushing glass that uses hammer mill blades that control the movement of a door for accessing the hammer mill blades. As shown previously, the base 128 of the apparatus 100 can have wheels to make it easier to move the apparatus. The apparatus 100 has a housing 120 having an upper chamber 122 and a lower chamber 124 being separated by a partition 360, a top 126 and a base 128. The upper chamber 122 is divided into a forward section 500 sometimes referred to as a loading bin area and a rearward section 230 sometimes referred to as an equipment area by a wall 362. The rearward section 230 is sealed from the forward section 500 and the lower chamber 124 by the wall 362 and the partition 360. Preferably, the lower chamber 124 defines a sidewall 126 having a door 134 disposed therein for removing the broken glass cullets 110. The forward section 500 defines an opening 510 therein that is positioned adjacent to the top of the housing. The partition 360 defines a hole 364 therein that is substantially the same size as the opening 510 defined by the forward section 500.
A motor means 356 is mounted within the rearward section 230 having a pulley shaft 620 connected to a hammer mill blade shaft 350 having a first end 352 and a second end 354. The first end 352 extends into the lower chamber 124. A first hammer mill blade 700 and a second hammer mill blade 720 are attached to the first end 352 of the hammer mill blade shaft 350.
A hinged lid 300 is attached to and in covering relationship with the opening 510 defined by the forward section 500. A funnel means 800 has mouth portion 810 and a neck portion 820. The mouth portion 810 is connected to the partition 360 and the neck portion 820 is connected to a receiving means. The funnel means 800 receives the crushed glass cullets and funnels them towards the receiving means 130. Preferably, there is a bar 382 attached to the mouth portion 810 of the funnel means 800 that is positioned parallel to the hammer mill blades 700 & 720 and extending inward toward the hammer mill blade shaft 350. The bar 382 keeps any glass pieces from resting on the top of the hammer mill blades.
There is a rotatable panel 600 that defines a hole 620 therein sized to fit the hole 364 formed by the partition 360 so that more than one glass container may be deposited into the apparatus at one time. The rotatable panel 600 is attached to a rotatable panel shaft 630. There is a weighing means 140 disposed in the base 128 of the housing and a means for cleaning 142 the forward section 500, the lower chamber 124, and the hammer mill blades.
In a preferred embodiment, the motor means 356 comprises a panel driving motor 220 and a hammer mill driving motor 210. The hammer mill driving motor 210 has a motor shaft 310 on which a sheave 200 is mounted. The sheave 200 is connected to the hammer mill blade shaft 350 by a hammer mill drive belt 190. The panel driving motor 220 is connected to the hammer mill driving motor 210 via a sprocket 250 and a chain drive means 270, so that the rotatable panel 600 is rotated in a plane that is horizontal with the partition 360 to an open position in response to the hammer mill driving motor 210 rotating. The hammer mill blade shaft 350 is surrounded by an inner tube 340 having a generally cylindrical shape, and the inner tube 340 is surrounded by an outer tube 170 having a generally cylindrical shape. The inner tube 340 and the outer tube 170 are sealed by a sealing means 330.
Preferably, the cleaning means comprises a first spray means 382 positioned inside the forward section 500, a second spray means 380 positioned inside the lower chamber 124, and a valve means 420 positioned adjacent to the base of the housing 120. The first spray means 382 is connected to the second spray means 380 and the valve means 420 by a conduit 390.
In yet another embodiment, there is provided a method for crushing glass containers. The method comprises providing an apparatus as described previously having hammer mill blades and a means for locking the door so the apparatus cannot be opened during operation. The apparatus is activated to crush glass containers into a plurality of cullets. The plurality of cullets are collected into a receiving means. The plurality of cullets are then weighed and the apparatus is deactivated when an amount of cullets reaches a predetermined weight.
While described herein in terms of preferred embodiments and methodologies with particularity, it will be obvious to those skilled in the art, however, that numerous additions, deletions, and modifications might well be made to the illustrated embodiments without departing from the spirit and scope of the invention as set forth in the claims. | An apparatus and method for smashing empty glass receptacles into predetermined sizes to facilitate the collection, storage, transportation and recycling of glass chard and/or cullets is disclosed. The apparatus includes a cabinet or housing that is comprised of two sections. The upper section has two compartments, a rear compartment that contains the motors, gears and electrical wiring. The upper front section has a hinged lid that can be opened to expose a loading trough. The lower section is sealed from the upper section by means of a partition that contains a rotary tray door that remains in the closed position until the upper lid has been closed and the safety circuit activated and the hammer mill blades have reached optimum revolution speed. The rotary hammer mill blades are attached by means of the vertical drive shaft at the under side of the upper and lower chamber partition just below the slideable tray door. The lower chamber also holds the glass chard or cullet collection container cradle frame. Another embodiment of the apparatus has a housing having an upper chamber and a lower chamber being separated by a partition, a top and a base. A motor means is mounted within the rearward section and has a pulley shaft connected to a hammer mill blade shaft that has a first end and a second end. The first end extends into the lower chamber. There is a rotatable panel that defines a hole therein sized to fit the hole formed by the partition. The rotatable panel is attached to a rotatable panel shaft. There is a weighing means disposed in the base of the housing and a means for cleaning the forward section, the lower chamber, and the hammer mill blades. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a throttle valve control system for opening and closing a throttle valve for use in an automobile by means of an actuator such as a motor or the like.
For an electronically controlled throttle system in which the throttle valve is operated by electronic control, in addition to such a case in which a throttle demand opening is instructed from an engine control system and it operates in response to this instruction, there is another case in which an electronically controlled throttle valve is provided independently of the engine control system for allowing operation by determining a control target position thereof by the electronically controlled throttle system itself. More specifically, there are such cases including: a case for driving its throttle to its close direction or to its open direction in order to learn a minimum position (full close learning) or a maximum position (full open learning); a case for driving its throttle by the steps of reading its acceleration pedal position, obtaining a corresponding throttle opening relative to the value read out from a look-up table or the like; or a case in which the electronically controlled throttle system drives its throttle without instruction from the engine control system when data exchange between the electronically controlled throttle system and the engine control system is interrupted. Because that the engine is driven based on an air flow quantity that is controlled by a throttle opening, and a fuel injection control and an ignition control in which the engine control system is involved, in case where the electronically controlled throttle system itself determines a control target for operation, in order appropriately to execute the fuel injection control, the ignition control and the like, it is necessary for the electronically controlled throttle system and the engine control system to exchange information and control the throttle in collaboration with each other.
For example, in the throttle full close position learning, all that is required is simply to operate the throttle valve until it makes contact with a stopper provided in its close direction, and it is not necessary for the engine to be rotating. In view of safety, it is rather preferable for the engine not working, thereby suppressing fuel injection and the engine should be stopped. In the full open learning, it is necessary for the engine to be controlled not to rotate. Further, in case a throttle opening is to be set up from a position of the acceleration pedal, it is necessary for the electronically controlled throttle system to inform a present position of the acceleration pedal to the engine control system such that the engine control system executes its engine control appropriately in response to the information.
Conventionally, in such a case as above, the electronically controlled throttle system and the engine control system are operated in synchronism with each other, and when the electronically controlled throttle system executes an operation that does not need engine speed, the engine control system is caused to take a measure to stop the engine operation. As a method for synchronizing therebetween, such methods have been utilized as one for taking a necessary step by exchanging contents of operation via a communication line therebetween, or one for monitoring a signal level of its ignition key and synchronizing at a period of timing of a change thereof.
However, as for the electronically controlled throttle system, it is more advantageous to be treated as a one unit and to minimize a relation with other systems, more specifically, interdependency with other systems, because a burden for newly incorporating the electronically controlled throttle system is substantially reduced. However, it should be noted that as described above, there is the case in which the electronically controlled throttle system depends on the behavior of the engine that is controlled by the engine control system.
SUMMARY OF THE INVENTION
An object of the present invention is to reduce an interdependency between the electronically controlled throttle system and the engine control system and improve a system reliability.
An electronically controlled throttle system of the invention monitors behaviors of an engine that is a target of direct control of an engine control system by means of an engine behavior monitor, and executes a fail-safe processing when a predetermined condition is not satisfied. An example of the engine behavior monitor is an engine speed monitor.
More specifically, when the electronically controlled throttle system of the invention controls its throttle independently of the engine control system, monitors engine behaviors using the engine behavior monitor, and if a predetermined condition is not satisfied, executes a fail-safe processing. For example, in the case in which the engine is controlled not to rotate in the step of the full open learning, when the engine behavior monitor that monitors engine speed indicates a value in excess of a predetermined speed, an engine control abnormality is judged to have occurred, and the electronically controlled throttle system terminates the full open learning operation abnormally. An advantage for allowing the electronically controlled throttle system also to monitor the engine behavior in addition to the monitoring and controlling by the engine control system resides in starting the fail-safe processing as quickly as possible and contributing to the improvement in the system reliability.
Because the full close learning or the full open learning are operations that do not require engine operation, there may be a case in which the electronically controlled throttle system and the engine control system are desired to be separated. Even in a state they are separated, in a method in which the electronically controlled throttle system is allowed to monitor the engine behavior, the electronically controlled throttle system is ensured to detect abnormality in the engine behavior and proceed to execute its fail-safe operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram indicating a first embodiment of the invention;
FIG. 2 is a schematic block diagram indicating a second embodiment of the invention;
FIG. 3 is a schematic block diagram indicating a third embodiment of the invention;
FIG. 4 is a schematic block diagram indicating a fourth embodiment of the invention; and
FIG. 5 is a schematic block diagram indicating a fifth embodiment of the invention.
DESCRIPTION OF THE INVENTION
Preferred embodiments of the invention will be described with reference to the accompanying drawings in the following.
FIG. 1 is a schematic block diagram indicating a first embodiment of the invention.
An electronically controlled throttle module 100 communicates with an engine control system 200 via a communication line 150 , receives a throttle demand opening 151 from engine control system 200 and transmits a throttle's present position 152 to engine control system 200 . Further, the same causes a throttle valve 115 to operate by driving a throttle actuator 110 . A position of throttle valve 115 is read using a throttle sensor 120 to be used as a feedback signal for driving throttle actuator 110 . Engine control system 200 reads an output of an air flow sensor 230 , and controls the output of an engine 250 by operating a fuel injection controller 210 and a ignition controller 220 . An engine speed that is a typical value for indicating engine behaviors is fed back to the engine control system, and is also read in electronically controlled throttle module 100 via engine speed monitor 280 .
The learning of the full close position of throttle valve 115 is executed by the electronically controlled throttle module 100 at the time when the ignition switch is turned on or off, under no throttle opening demand from engine control system 200 . Electronically controlled throttle module 100 causes throttle actuator 110 to drive the throttle in the direction of closure, during which, reads values of throttle sensor 120 , and sets up a value of throttle sensor 120 which is judged to have reached its minimum as a learned full closure value. At this stage, electronically controlled throttle module 100 notifies engine control system 200 completion of the full close position learning via communication line 150 . Until the notification of the completion of the full closure learning from electronically controlled throttle module 100 , engine control system 200 does not drive fuel injection controller 210 and ignition controller 220 , and upon notification thereof, drives fuel injection controller 210 and ignition controller 220 to start the engine control operation.
In the process of the full closure learning by electronically controlled throttle module 100 , if engine control system 200 misjudges that the electronically controlled throttle module 100 does not execute the full closure learning, the engine control system 200 attempts to control engine 250 by operating fuel injection controller 210 and ignition controller 220 , however, because that throttle valve 115 is driven to its full closure position, there is a probability for the engine 250 to become in a state of engine stall. At this moment, in the case in which a full open learning is to be executed, its engine speed increases with opening of throttle valve 115 in such a case as above. However, according to the invention, because electronically controlled throttle module 100 monitors the revolution of engine 250 via engine speed monitor 280 , when it senses an increase in the engine speed, interrupts its full open learning and closes throttle valve 115 , thereby capable of suppressing the output of engine 250 .
In the case described above, when engine speed monitoring unit 280 malfunctions, the state of the engine 250 cannot be known. Therefore, according to the invention, its full open learning is interrupted in the same way as in the case where the engine speed monitoring unit 280 operates normally and an increase in the engine speed is sensed. Malfunctioning of engine speed monitor 280 probably occurs due to a short-circuit or open-circuit of wiring, and can be detected by a change in the output level of engine speed monitor 280 .
The foregoing description has been made by way of examples of the full close and the full open learning operations, however, it may also be applied to a case in which a throttle return spring is to be checked. When the throttle control becomes abnormal, throttle valve 115 stops the motor drive as a fail-safe procedure. A return spring is provided for ensuring the throttle valve to return to a predetermined position (a default position) at this instant. The default position is set, not at the full closure position, but mostly at a position at which the throttle valve 115 is slightly open. This is because of ensuring that even if the motor drive is stopped as the fail-safe procedure under abnormality of the throttle control, the vehicle may be moved at least to a safety position. In order to allow for the throttle valve 115 to be moved to a predetermined position at the time when the motor drive is stopped, two kinds of throttle return springs are used for urging throttle valve 115 into both directions of an open and a closure directions. Diagnosis of these two springs whether or not they function normally is done by observation that throttle valve 115 returns to its default position from its full open position and full close position after it is driven thereto, and then the motor drive is stopped. Also, in the diagnosis of this operation, this embodiment of the invention is applicable.
A second embodiment of the invention is indicated in FIG. 2, in which engine speed monitor 280 indicated in FIG. 1 of the first embodiment of the invention is eliminated, and instead thereof, its engine speed is notified from engine control system 200 to electronically controlled throttle module 100 via communication line 150 . In the electronically controlled throttle module 100 , only a means for knowing its engine speed is changed, and its operating principle is the same as in the case of FIG. 1 . Further, such a case in which the electronically controlled throttle module 100 fails to learn the engine speed due to abnormality in communication line 150 corresponds to the case of malfunctioning of engine speed monitor 280 described with reference to FIG. 1 .
A third embodiment of the invention will be described with reference to FIG. 3. A driver's intent input device 300 is typically represented by an acceleration pedal, and when the driver operates the pedal, it outputs a value in response to its control quantity. Electronically controlled throttle module 100 reads an output value from driver's intent input device 300 , and obtains a first throttle target opening by means of a driver's intent/throttle opening converter 310 . Further, an engine control demand opening converter 320 calculates a second throttle target opening on the basis of the throttle demand opening value received from engine control system 200 via communication line 150 . A final throttle target opening arithmetic unit 330 adds the first throttle target opening and the second throttle target opening, and drives throttle actuator 110 in accordance with a value obtained as a result of addition.
In the process of receiving a throttle demand opening value from engine control system 200 via communication line 150 according to this embodiment of the invention, it may be considered that the throttle demand opening value cannot be received properly due to a failure such as open circuit, short circuit, or by noise. In such cases, according to this embodiment of the invention, a predetermined value is used as a throttle demand opening value.
A fourth embodiment of the invention, which is a modification of the third embodiment above, will be described with reference to FIG. 4 . In this embodiment of the invention, a throttle demand opening buffer 321 is added to in comparison with the configuration of FIG. 3 . Engine control demand opening converter 320 , everytime it calculates a second throttle target opening on the basis of the throttle demand opening value received from engine control system 200 via communication line 150 , stores a result of its calculation in throttle demand opening buffer memory 321 . In case electronically controlled throttle module 100 is unable to receive the throttle demand opening value properly, a second throttle target opening value is calculated on the basis of the values stored in throttle demand opening buffer memory 321 . At this time, as methods of the above calculation, there are such ones as follows. Simply to continue to use the value stored in throttle demand opening buffer 321 , to use a value which is obtained by subtracting a predetermined value from the value stored in throttle demand opening buffer memory 321 , or to change the value to be used along a curve predetermined relative to the value stored in throttle demand opening buffer 321 .
A fifth embodiment of the invention will be described with reference to FIG. 5 . In this embodiment of the invention, a target opening select information 153 is received from engine control system 200 . Target opening select information 153 is either value of 1, 2 and 3, and each of which means as follows.
1: its final throttle target opening is to be obtained by addition of values of the first throttle target opening and the second throttle target opening,
2: its final throttle target opening should be the first throttle target opening, and
3: its final throttle target opening should be the second throttle target opening.
A case where its target opening select information 153 is “1” corresponds to a normal case; another case where its target opening select information 153 is “2” corresponds to a case in which an output from driver's intent input device 300 is to be disregarded, wherein its throttle is controlled in accordance with the first throttle target opening requested by engine control system 200 even if the acceleration pedal is not pressed, which corresponds to a case of a cruising state; and the remaining case where its target opening select information 153 is “3” corresponds to a case in which the first throttle target opening received from engine control system 200 is to be disregarded, wherein the second throttle target opening that is calculated on the basis of the throttle demand opening value received from engine control system 200 via communication line 150 is disregarded due to detection of abnormality in communication with engine control system 200 , even if the communication therebetween is recovered, thereby operating throttle valve 115 only according to a value read from driver's intent input device 300 .
According to the invention, even in such a case where the throttle valve is operated independently of the engine control system, it is enabled to detect occurrence of abnormality in the engine and execute a necessary fail-safe procedure. | Even in such an arrangement in which the throttle valve is operated independently of the engine control system, abnormal engine behavior is ensured to be detected such that a necessary fail-safe operation should be taken. The arrangement of the invention is comprised of the electronically controlled throttle system, engine control system and engine speed monitoring unit, wherein the electronically controlled throttle system is allowed to monitor engine behaviors. Thereby, in the case when the throttle valve is operated independently of the engine control system, if its engine behavior becomes abnormal relative to its drive contents, the engine system senses the abnormality, and takes a fail-safe operation such as to stop operation of the throttle valve and the like. | 5 |
FIELD OF THE INVENTION
[0001] The present invention concerns a card incorporating an electronic display. This electronic display is generally associated with an electronic data processing circuit and, in some variants, with a switch or sensor enabling a user to activate a certain function. The electronic display can display variable codes and other data for increasing the security of bankcards or secure access cards, for example. Integrating an electronic display in a card causes a particular manufacturing constraint, given that the card has to be transparent above the display. The electronic display module is located inside the card according to the invention. Thus, the display module is covered by at least one additional outer protective layer.
BACKGROUND OF THE INVENTION
[0002] According to an advantageous method of manufacturing cards incorporating various electronic elements, the electronic elements are coated or embedded in a resin that forms a core or intermediate layer of the card. EP Patent No. 0 570 784 generally discloses a manufacturing method of this type. In order to obtain a core that has flat, uniform surfaces, it is preferable to coat all of the electronic elements incorporated in the card and thus to cover the electronic display with the resin coating. In this latter implementation made, the resin must be transparent at least in the display area. The transparency of the resin causes a problem as regards obtaining high quality printing, in particular on the top surface of the card where the display appears. Consequently, it raises a dual problem. Generally speaking, printing patterns on a transparent layer causes a decrease both in colour intensity and contrast, so that the colours have a translucent appearance. Secondly, the presence of various electronic elements in the transparent core causes variations in light reflected by the core, which results in darker areas on the surfaces of the core. The support on which a pattern is printed is thus not optically uniform, which generally leads to variations in contrast and variations in colour intensity on the top surface side of the finished card.
[0003] In order to overcome the aforementioned problem, in manufactured cards of the prior art, a light-coloured, preferably white, ink or varnish is deposited underneath the printed patterns relative to the core of the card, via a silkscreen printing technique, so that the thin layer of ink or varnish has a certain thickness. Two variants of cards made in accordance with this technique are shown in FIGS. 1 and 2 .
[0004] Card 2 of FIG. 1 is formed of a core 4 incorporating an electronic unit 8 and an electronic display 10 . These electronic elements 8 and 10 are embedded in a transparent resin 6 that forms core 4 , which is made in a first step of a manufacturing method for such cards. Core 4 is formed by a technique known to those skilled in the art, in particular in a press or by injecting the resin into a mould. Next, a transparent film 12 is arranged on the top surface side of the core, on the inner surface of which a pattern 14 is printed. To obtain high quality printing, i.e. high definition, printed patterns 14 are preferably obtained by an offset printing technique. Then, according to this prior art method, a layer of ink or varnish 16 is printed on pattern 14 . This layer 16 is preferably white and it extends over the entire bottom surface of transparent film 12 except for the display area located above electronic display 10 . Layer 16 thus defines a window through which electronic display 10 is visible.
[0005] Likewise, a transparent film 18 is arranged on the bottom surface side of the card 2 , on the top surface of which a pattern 20 is printed. This pattern 20 is covered by a layer of ink or varnish 22 . Layer 22 is also preferably deposited by silkscreen printing. However, it should be noted that bottom layers 16 and 22 might be deposited by various techniques.
[0006] Card 22 according to the variant shown in FIG. 2 includes a core 24 formed of a resin or any material 26 . Core 24 differs from core 4 of FIG. 1 in that the electronic display 10 at the top surface thereof is flush with the top surface of core 24 . Unlike the preceding variant, material 26 does not have to be transparent here. Material 26 may be added in liquid form in a press or injection moulding installation, as for core 4 of FIG. 1 . In another method of manufacturing core 24 , electronic display 10 can be inserted in a shell with a preformed housing or in the aperture of a layer forming core 24 , which may be formed of one or several layers assembled by lamination or by press bonding. In order to have a flat, uniform support for printing pattern 14 , a transparent film 30 is arranged on the top surface of core 24 . A layer of ink or varnish 16 is deposited on the top surface of film 30 , leaving a window for electronic display 10 . Pattern 14 is printed on this bottom layer 16 by an offset technique. A transparent external film 12 is then assembled to printed film 30 . A fine layer of adhesive or resin is provided between printed film 30 and external film 12 to increase adherence between these two transparent films. On the bottom surface side of card 22 , an opaque layer 32 is arranged against the core, on the bottom surface of which a pattern 20 is printed. This pattern 20 is then covered by a transparent external film 18 by means of a thin layer of adhesive or resin 36 .
[0007] Besides problems linked to the thickness of card 22 , when developing the present invention it was observed that embodiments of cards 2 and 22 did not efficiently resolve the previously identified problem, i.e. the problem of a decrease in contrast and low colour intensity due to the presence of a transparent layer or film behind the printed patterns 14 . Two major problems appear with the embodiments described with reference to FIGS. 1 and 2 .
[0008] First of all, the deposition of layer 16 by a printing technique does not provide a perfectly opaque background. Various experiments have demonstrated that it is necessary to deposit several layers particularly by silkscreen printing in order to obtain an opaque background providing a satisfactory visual appearance for high quality cards. Moreover, the inks or varnish that can produce this opaque background 16 are the type that have two components. Such inks or varnish have a relatively long drying time, which raises several manufacturing problems. Thus, the time necessary for printing or depositing several layers of varnish or ink for the opaque background is considerable. This raises a storage problem during the drying periods for each print or ink or varnish deposition. This results in a relatively expensive manufacturing method requiring a large storage capacity. This storage is not easy either since the printed films must not be touched during the drying periods.
[0009] The second major problem is the problem of adherence of the transparent external layer 12 in finished cards 2 and 22 . The patterns 14 made by an offset printing technique adhere relatively poorly to the transparent plastic film 12 . To increase the adherence of this external layer, printed pattern 14 is generally either covered with a thin layer of adhesive or resin that adheres well to the transparent plastic film used. If the two bottom layers 32 and 18 of card 22 are laminated to each other with a printed pattern 20 and fine layer of adhesive 36 between them, the adherence between layers 32 and 18 is sufficient. It was observed that this is due to the fact that adhesive 34 slightly penetrates the printed pattern and creates a multitude of anchorage points with the layer or film on which pattern 20 is printed. In other words, printed pattern 20 is sufficiently permeable to the adhesive for the latter for form a real adherence interface between the two plastic films or layers. The same effect is observed in the case of a similar card to that of FIG. 1 where only printed patterns 14 and 20 are provided. By selecting a resin 6 that adheres well to transparent layers 12 and 18 , these layers have sufficient adherence to core 4 because resin 6 penetrates slightly printed patterns 14 and 20 during the card lamination assembly operation. Thus, it has been observed that the presence of the bottom layer forms a barrier to the adhesive or to the resin such that they can no longer ensure the proper adherence of layer 12 in cards 2 and 22 , and respectively of layer 18 in card 2 .
SUMMARY OF THE INVENTION
[0010] After highlighting the various aforementioned problems in the envisaged prior art solutions, shown in FIGS. 1 and 2 , it is an object of the present invention to propose a solution for overcoming the aforementioned problems and to provide a card with an integrated electronic display therein, yet which has a very high quality printed pattern on the top surface thereof.
[0011] The present invention therefore concerns a card comprising an electronic display, arranged in a core of said card, and above said core a plastic layer, the greater part of which is formed of an opaque material and of a transparent material in a display part located above said electronic display. This transparent material defines a window for reading the electronic display.
[0012] In a main variant, the plastic layer forms a printing support or substrate for at least one printed pattern on the opaque part of the plastic layer. Preferably, the opaque material is white.
[0013] In a preferred variant, the plastic layer is formed of a sheet made of said opaque material, in which an aperture has been made in said display area. A transparent plate is arranged in said aperture. The thickness of the plate is preferably approximately equal to that of the opaque sheet.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The present invention will be described in more detail in the following description, made with reference to the annexed drawings, given by way of non-limiting example, in which:
[0015] FIGS. 1 and 2 respectively show two transverse cross-sections of cards made in accordance with a method prior to the present invention;
[0016] FIG. 3 is a transverse cross-section of a card according to the present invention;
[0017] FIG. 4 shows an alternative embodiment of the card according to the invention;
[0018] FIG. 5 shows a pierced opaque sheet involved in forming the card of FIGS. 3 and 4 ;
[0019] FIG. 6 shows schematically a first variant of a printed opaque sheet that has windows filled with a transparent material; and
[0020] FIG. 7 shows how one part of the card shown in FIG. 3 is formed in accordance with a specific manufacturing method.
DETAILED DESCRIPTION OF THE INVENTION
[0021] FIG. 3 shows an embodiment of a card according to the invention. This card 38 has a core 4 , similar to the core of card 2 of FIG. 1 , in which an electronic unit 8 and electronic display 10 are embedded. Core 4 is formed by a transparent resin 6 , which also covers electronic display 10 . The electronic elements are thus coated or embedded in resin 6 , which defines a compact core with two approximately flat surfaces. It will be noted that, in other variants of the cores, the electronic elements are merely covered by the resin without being entirely coated by said resin.
[0022] A layer 40 , formed partly by an opaque material 42 and by a transparent material 44 , is arranged on core 4 , above electronic display 10 such that the display is visible from outside card 38 . The greater part 42 of layer 40 is formed of opaque material, which is preferably white. Only one aperture 46 , defined by opaque part 42 in the display area above electronic display 10 , is filled by a transparent part 44 . This aperture 46 defines a window whose dimensions are such that only the part used for the display of characters, numbers or other patterns of display unit 10 is visible. The thickness of transparent part 44 is approximately equal to that of opaque part 42 . Thus, outside window 46 , layer 40 defines a perfectly opaque light-coloured background for printing patterns 14 on the top surface of layer 40 . Pattern 14 is preferably printed by an offset technique. A transparent external layer 12 is arranged on printed layer 40 , using a thin layer of adhesive 34 ensuring that external layer 12 adheres properly to intermediate layer 40 . As previously explained, given that it is only necessary to print a pattern, in particular in an offset printing installation, the thin layer of adhesive really defines an adherence interface between layers 40 and 12 . The problems mentioned in relation to cards 2 and 22 of the prior art are thus solved by card 38 according to the invention.
[0023] In order to obtain a symmetrical card that also has a high quality print on the bottom surface of the card, an opaque layer 32 is added, on the bottom surface of which a pattern 20 is printed. Next, a transparent external layer 18 , coated with a thin layer of adhesive 36 is added against printed sheet 32 . The whole assembly is laminated in a press or using laminating rollers to ensure its assembly. Cards are thus obtained that have an integrated electronic display inside the card, visible through transparent layers or films, while outside the display area there is a print on a relatively thick opaque layer that allows very good contrast and good colour intensity. It will be noted that one could envisage having an electronic display on the bottom surface of the card or on the two sides of the card.
[0024] Card 48 shown in cross-section in FIG. 4 is a variant made from a similar core 24 to that of card 22 shown in FIG. 2 . On the top surface of core 24 there is a layer 40 of plastic material, the greater part 42 of which is formed of an opaque material. In the display area located above display unit 10 , layer 40 has a part 44 formed of a transparent material. A printed pattern 14 is provided on opaque part 42 . The printed layer 40 is covered with a transparent film 12 . In this variant, there is no thin layer of adhesive between layer 40 and film 12 . However, in another variant, a film acting as adherence interface may be arranged between layer 40 and external film 12 . It will be noted that it is also possible to provide a thin layer of resin or adhesive between plastic layer 40 and core 24 to ensure that plastic part 40 adheres well to electronic display 10 . This fine layer of adhesive is advantageously applied on the bottom surface of layer 40 before assembly to core 24 . The thin adhesive layer may alternatively be deposited beforehand on the top surface of core 24 or be added in the form of a thin sheet arranged between layer 40 and core 24 . These different alternatives and variants also apply to the arrangement of a fine layer of adhesive or resin between layer 40 and external layer 12 .
[0025] Pattern 14 can be printed, in a variant, on the bottom surface of transparent film 12 . This transparent film is then positioned such that printed pattern 14 is opposite opaque part 42 .
[0026] On the side of the bottom surface of core 24 an opaque layer 32 and a transparent external film 18 are arranged, with a printed pattern 20 between them.
[0027] It will be noted that a transparent lacquer may replace transparent external films 12 and 18 , for example, or any other transparent material that can protect printed patterns 14 and 20 .
[0028] FIG. 5 shows a pierced plastic sheet 50 used to form layer 40 for a plurality of batch-manufactured cards. The contour 58 of the cards, obtained after cutting the finished cards from the batch, is represented by a dotted line. The sheet 50 has an aperture 46 for each card. The largest part 42 is formed by the opaque material of sheet 50 , particularly PVC. Patterns 14 can be printed on this sheet either before making apertures 46 , or after this operation. Printing beforehand provides a printed pattern that perfectly surrounds the aperture provided for each card.
[0029] FIG. 6 shows an intermediate product 52 involved in a first implementation of a card manufacturing method according to the invention.
[0030] Intermediate product 52 is formed of sheet 50 , shown in FIG. 5 , which defines a plurality of opaque parts 42 for a corresponding plurality of cards. In apertures 46 of sheet 50 there are transparent parts 44 , which have approximately the same thickness as parts 42 , so as to form an intermediate product 52 that defines a flat structure. A plurality of patterns 14 is printed on the top surface of sheet 50 . Transparent parts 44 are preferably formed by plates cut from a transparent sheet and inserted into apertures 46 . Plates 44 can be obtained in other ways known to those skilled in the art.
[0031] Those skilled in the art can use various assembly techniques to ensure that plates 44 remain in place until the step for laminating them to the cores of the manufactured cards. For example, a few weld spots can be made using a simple heated tool tip, applied to the edge of apertures 46 . The plastic material melts locally, which creates weld spots and thus assembles plates 44 to sheet 50 . These weld spots are preferably made on the bottom surface of sheet 50 , i.e. on the side opposite the printed surface. However, it is also possible to make these weld spots carefully on the side of the printed surface, in particular when printing is carried out subsequently. It is also possible to secure plates 44 using an adhesive. This bonding step to keep transparent plates 44 in place may be combined with the deposition of a thin layer of adhesive on the bottom surface and/or the top surface of intermediate product 52 . Transparent plates 44 may also be assembled to pierced plate 50 in a laminating step. It will be noted that this lamination may also be provided in addition to the aforementioned spot assembly. Providing heat can thus at least partially weld the lateral faces of the plates to the wall of the corresponding apertures 46 and provide a flat, uniform layer. The layer may then be used in a method of forming cards at a relatively low temperature.
[0032] Intermediate product 52 is particularly advantageous for a method where patterns 14 are printed after the opaque sheet has been assembled to the transparent plates, as the printing can then also partially cover the transparent plates.
[0033] The transparent parts 44 may, in another way of making cards according to the invention, be obtained by injecting a transparent material through windows 46 .
[0034] FIG. 7 shows a cross-section of another intermediate product 54 obtained within a second implementation of a card manufacturing method according to the invention. To obtain intermediate product 54 , opaque sheet 50 is first printed to obtain a plurality of patterns 14 . Then, a transparent film 12 covered with a layer of adhesive 34 is placed against sheet 50 on the side of printed patterns 14 . Printed sheet 50 is then assembled to transparent film 12 and housings are obtained formed by apertures 46 that have adhesive layer 34 at the bottom thereof. Transparent plates 44 are then inserted into apertures 46 and secured to film 12 via the locally heated adhesive layer, for example. An intermediate product 54 is thus obtained which can then be assembled to a core 4 or 24 to provide cards according to the present invention. It will be noted that this intermediate product can also be obtained without the adhesive layer. In this latter case, the temporary assembly is achieved via a weld spot on one side or the other, on the edge of the apertures or at the centre, by welding the plates to transparent film 12 . Preferably, the assembly thereby obtained is then laminated to obtain a properly flat, multi-layered structure, without slots and without any marks that could result from the temporary assembly of the transparent plates.
[0035] In a method where the core is not made in a prior step, but is formed simultaneously while the whole card is being formed, intermediate product 54 is then used as a top, multi-layered structure, arranged in the laminating installation (flat press or rollers) on a resin in a viscous liquid state used to form a central core incorporating the electronic elements. A bottom sheet or multi-layered structure is generally arranged underneath the resin that is added in the laminating installation. Pre-assembled layers 18 and 32 , as shown in FIG. 3 or 4 , may form this bottom multi-layered structure. The top and bottom multi-layered structures are generally laminated at a relatively high temperature, but the entire card is finally made at a low temperature or ambient temperature, to prevent damaging the electronic elements.
[0036] It will be noted finally that transparent part 44 of plastic layer 40 may have various optical functions, particularly polarising or filtering functions, and have undergone various treatments, particularly an anti-reflective treatment. In an advantageous variant, this transparent part defines a Fresnel lens, which gives a magnifying effect. These functions or optical treatments are used first and foremost for increasing the reading comfort of the electronic display. However, they may also be used to give a certain visual or aesthetic appearance. | The invention relates to a card ( 38 ) including a digital display ( 10 ) arranged in a node ( 4 ) defining the central portion of the card. It further comprises a plastic layer ( 40 ) the major portion ( 42 ) of which is opaque, and a transparent display portion ( 44 ). A pattern ( 14 ) is printed on the upper face of the plastic layer ( 40 ), in particular by an offset printing technique. The plastic layer ( 40 ) is covered with a transparent film ( 12 ) attached thereto by a thin glue layer ( 34 ) defining an adhesion interface. The electronic display ( 10 ) is fully integrated in the card ( 38 ) and the printed pattern ( 14 ) exhibits a good contrast on the opaque portion of said plastic layer. Furthermore, a good adhesion is obtained between all the layers of the card. | 6 |
BACKGROUND
[0001] The invention relates to an apparatus and method of preventing unauthorized access to data stored on a mobile device.
DESCRIPTION OF RELATED ART
[0002] Traditionally, stored data is protected through the mean of a password. Those traditional methods require that the users manually provide their identifier for each data access. Those methods also require the installation of specialized drivers in the host machine of the storage device. So, for example, a secured USB key could only be accessed on computer on which the security software has been installed, preventing their use as back-up or data transfer systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] FIG. 1 shows a possible embodiment of the invention, in which a control device ( 101 ) is used to manage all data and information exchange within the secure storage system
[0004] FIGS. 2 and 3 show possible embodiments in which the data path and the security subsystem are decoupled as to accelerate data exchange between the secure storage system and its host
[0005] FIG. 4 shows a possible implementation in which the secure storage is used to enable a function depending on the presence of a reference device in close proximity.
[0006] FIG. 5 shows a possible implementation in which the function of the secure storage is enabled or disabled by a host system, depending on the presence of a reference design in close proximity.
DETAILED DESCRIPTION
[0007] According to one embodiment of the invention, the storage device may be equipped with a short range wireless subsystem, including a radio. The storage device may utilize the wireless subsystem to detect the presence of a reference wireless device, such as a cell phone, laptop or specially designed device within a close proximity. Once the reference device is detected, the data storage device becomes accessible. In one embodiment, if the reference device is absent from the wireless range, protective actions may be taken by the storage device, such as locking access to the data, erasing the data, or sending an alarm message.
[0008] Referring to FIG. 1 , in one embodiment, the secure data storage ( 10 ) may be made up of four different devices: a host interface device ( 102 ) that connects to host systems ( 11 ) such as computers or servers for example, using a data link ( 13 ) such as USB, SATA or others; a storage device ( 103 ) such as but not exclusive to a flash optical storage; a communication device ( 104 ) using protocols such as but not exclusive to Bluetooth or RF_ID to detect the presence of a reference security system ( 12 ) such as, but not exclusive to, a cell phone or an RF-ID tag; and a control device ( 101 ), such as but not exclusive to a micro-controller or micro-processor. In this embodiment, the Host System ( 11 ) performs a data access request through the data link ( 13 ). The Host Interface Device ( 102 ) notifies the Control Device ( 101 ) that a data request took place. The Control Device ( 101 ) then asks the Communication Device ( 104 ) to check for the presence of the Reference Security System ( 12 ) in the vicinity. For example, in the case of a Bluetooth protocol, the Communication Device ( 104 ) will check that a Phone with the right ID is present. If the Reference Security System ( 12 ) is detected, the data access is granted to the Host System ( 11 ). Note that the Reference Security System ( 12 ) ID can be stored in the Storage Device ( 103 ) or any other storage device in the apparatus. The apparatus might be kept in an unlocked state until a Reference Security System ( 12 ) is associated to it by the user, or can be associated to a Reference Security System in the factory. An example of factory association would be to associate a secured USB storage key with one or more key chain RF ID tags.
[0009] In another embodiment, the Storage Device ( 103 ) can be partitioned. Each partition may be associated to one or more Reference Security System ( 12 ), a map of those associations can then be stored in the apparatus. The map might be a separate partition in the storage device ( 103 ) associated to its own Reference Security System ( 12 ). The map can then only be modified if its Reference Security System ( 103 ) is present. One example application would be in a business environment where the user of a laptop or USB key will have access to a storage partition using their badge equipped with an RF-ID tag while the IT department will have access to the partition map using a separate badge, allowing them to reset the partition association in case of incident such as the loss of the employee badge.
[0010] In another embodiment, the Secure Storage ( 10 ) may use build-in feature of the protocol used as the security link ( 14 ) to establish a connection with the Reference Security System ( 12 ) and only unlock access to the Storage Device ( 103 ) when this connection is established. In such case, access to the Storage Device ( 103 ) is blocked as soon as the connection between the Reference Security System ( 12 ) and Secure Storage ( 10 ) is broken.
[0011] In another embodiment, the secure Storage would be USB key or external Hard drive associated to a cell phone via Bluetooth. In this embodiment, the Personal Computer ( 11 ) performs a data access request through the USB interface ( 13 ). The microcontroller ( 101 ) build in the Storage device ( 10 ) check for the presence of the Mobile Phone ( 12 ) using the built-in Bluetooth radio ( 104 ). The close Range nature of Bluetooth ensures that the Mobile Phone can only be detected when in close proximity. If the Mobile Phone ( 12 ) is detected, the data access is granted to the Host System ( 11 ). In such an embodiment, the associated mobile phone unique ID can be stored in storage ( 103 ).
[0012] In another embodiment described in FIG. 1 ( f ), the secure Storage would be an internal Hard drive associated to a cell phone via a built-in Bluetooth. In this embodiment, the Personal Computer's Motherboard ( 11 ) performs a data access request through the SATA interface ( 13 ). The microcontroller ( 101 ) build in the Storage device ( 10 ) check for the presence of the Mobile Phone ( 12 ) using the built-in Bluetooth radio ( 104 ). The close Range nature of Bluetooth ensures that the mobile Phone can only be detected when in close proximity. If the Mobile Phone ( 12 ) is detected, the data access is granted to the Mother Board ( 11 ). In such an embodiment, the associated mobile phone unique ID can be stored in storage ( 103 ).
[0013] In another embodiment described in FIG. 1 ( g ), the secure Storage would be an external Storage Device associated to a card or badge equipped with a RFID chip. In this embodiment, the Personal Computer ( 11 ) performs a data access request through the USB interface ( 13 ). The microcontroller ( 101 ) build in the Storage device ( 10 ) check for the presence of the associated Card or Badge ( 12 ) using the built-in RFID radio ( 104 ). The close Range nature of RFID ensures that the associated Card or Badge can only be detected when in close proximity. If associated Card or Badge ( 12 ) is detected, the data access is granted to the Personal Computer ( 11 ). In such an embodiment, the associated mobile phone unique ID can be stored in storage ( 103 ).
[0014] In another embodiment, referring to FIG. 2 , the control device ( 204 ) is taken out of the data path as to increase the data exchange speed. In this embodiment, the control device is used to control the access rights through the host interface device ( 202 ).
[0015] In another embodiment, referring to FIG. 3 , a timer device ( 305 ) is added to the system as to conduct periodic check of the presence of the Reference Security System ( 32 ). If Reference Security Systems ( 32 ) are present, the Storage Device ( 103 ) partitions associated to them become unlocked until the next periodic check takes place. If some Reference Security Systems ( 32 ) are absent, the Storage Device ( 103 ) partitions associated to them become locked until the next periodic check takes place. If the Host System ( 31 ) tries to access a locked partition of the Data storage ( 303 ), the control device ( 301 ) will start the sequence to determine if the Reference Security Systems ( 32 ) is now present.
[0016] In another embodiment, the apparatus will take protective measures if a certain number of consecutive data access from the Host System have been rejected. Those measures could be such as erasing the data of the partition being targeted by the host system, encrypting the data of the partition being targeted by the host system, sending an alert message in the case of an apparatus connected to a communication network, adding a secondary level of security such as predetermined password.
[0017] In another embodiment, the security method can be combined with other method such as encryption and passwords.
[0018] In another embodiment, referring to FIG. 4 , the storage device ( 403 ) is used to store a map associating Reference Security Systems with predetermined functions of the Secure Device ( 40 ). When a Host System ( 41 ) request the Secure Device ( 40 ) to perform a function, the Secure Device ( 40 ) uses the method described above to check for the presence of the Reference Security System ( 42 ) associated with the function. Such an apparatus can be implemented on payment devices such as credit cards and only allows transactions to be made if the Reference Security System is present in the vicinity.
[0019] In such an embodiment, described in FIG. 4 ( d ), the Host System can be a credit card payment terminal ( 41 ) and the Secure Storage Device a credit card ( 40 ) equipped with a SmartChip ( 401 ). The payment terminal ( 41 ) will first request the Credit card SmartChip ( 401 ) to provide the ID of its associated Reference Security System, usually a mobile phone. The payment terminal will then use the Bluetooth or similar close range Protocol ( 44 ) to check for the presence of the Reference Security System ( 42 ) within Close Range. The credit card ( 40 ) usage will only be allowed by the payment terminal ( 41 ) if the Reference Security System ( 42 ) is detected.
[0020] In another embodiment, described in FIG. 4 ( f ), the Host System can be a credit card payment terminal ( 41 ) and the Secure Storage Device a credit card ( 40 ) equipped with a SmartChip ( 401 ) and an RFID radio. The Credit card SmartChip ( 401 ) will only provide information stored in its internal storage ( 403 ) to the payment terminal ( 41 ) if it can access its Reference Security System ( 42 ) using its built-in RFID radio. ( 404 ). The inherent short range nature of RFID will ensure that a detected Reference security system is within close range. The reference Security System may be a mobile phone or a card with built-in RFID chip.
[0021] In another embodiment, described in FIG. 5 , the host system ( 51 ) will first request the Secure Device ( 50 ) to provide its own ID stored in built-in storage device ( 503 ). The Host System ( 51 ) will then obtain the Reference Security System ( 52 ) ID from a central database ( 55 ) using the Secure Device ( 50 ) ID. The Host System will then use the Bluetooth or similar close range Protocol ( 54 ) to check for the presence of the Reference Security System ( 52 ) within Close Range. The function associated with the Secure Device ( 50 ) will only be performed by the host system if the Reference Security System ( 52 ) is detected within close range. The inherent short range nature of the security link ( 54 ) will ensure that a detected Reference Security System ( 52 ) is within close range.
[0022] In such an embodiment, described in FIG. 5 ( c ), the Host System can be a credit card payment terminal ( 51 ) and the Secure Storage Device a credit card ( 50 ) equipped with a SmartChip ( 501 ). The payment terminal ( 51 ) will first request the Credit card SmartChip ( 501 ) to provide its own ID. The payment terminal ( 51 ) will then obtain the Reference Security System ( 52 ) ID from a central database ( 55 ) using the SmartChip ( 501 ) ID. The payment terminal will then use the Bluetooth or similar close range Protocol ( 54 ) to check for the presence of the Reference Security System ( 52 ) within close range. The credit card ( 50 ) usage will only be allowed by the payment terminal ( 51 ) if the Reference Security System ( 52 ) is detected. The inherent short range nature of Bluetooth ( 54 ) will ensure that a detected Reference Security System ( 52 ) is within close range.
[0023] In another embodiment, described in FIG. 5 ( b ), the Host System can be a credit card payment terminal ( 51 ) and the Secure Storage Device a credit card ( 50 ) equipped with a Magnetic stripe ( 503 ). The payment terminal ( 51 ) will first read the credit card ( 50 ) ID from the Magnetic Stripe ( 503 ). The payment terminal ( 51 ) will then obtain the Reference Security System ( 52 ) ID from a central database ( 55 ) using the credit card ( 50 ) ID. The payment terminal will then use the Bluetooth or similar close range Protocol ( 54 ) to check for the presence of the Reference Security System ( 52 ) within close range. The credit card ( 50 ) usage will only be allowed by the payment terminal ( 51 ) if the Reference Security System ( 52 ) is detected.
[0024] Generally, in one embodiment, provided is a data storage device having of the storage itself and a wireless communication interface used to secure the data. Below are further examples of various other embodiments and features that may be included in such a device.
[0025] The data may be accessed via a USB protocol.
[0026] The wireless communication protocol used for securing the data may be RF-ID, Bluetooth, Wi-Fi or other protocols.
[0027] The data storage may be different types of memory, including a hard disk-drive, Flash, or other types of memory.
[0028] The data storage may be partitioned, with each partition having a different security profile, with some partitions being secured and some being unsecured
[0029] The data may be erased after a certain number of unsuccessful data access attempts.
[0030] The data storage device my include the storage itself and a wireless communication interface used to secure the data, wherein the data storage is partitioned, with each partition having a different security profile.
[0031] In the following disclosure, numerous specific details are set forth to provide a thorough understanding of the invention. However, those skilled in the art will appreciate that the invention may be practiced without such specific details. In other instances, well-known elements have been illustrated in schematic or block diagram form in order not to obscure the invention in unnecessary detail. Additionally, for the most part, details concerning network communications, data structures, and the like have been omitted inasmuch as such details are not considered necessary to obtain a complete understanding of the invention, and are considered to be within the understanding of persons of ordinary skill in the relevant art. It is further noted that all functions described herein may be performed in either hardware or software, or a combination thereof, unless indicated otherwise. Certain terms are used throughout this description and claims to refer to particular system components. As one skilled in the art will appreciate, components may be referred to by different names. This document does not intend to distinguish between components that differ in name, but not function. In the following discussion and in the claims, the terms “including”, “comprising”, and “incorporating” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . ”. Also, the term “couple” or “couples” is intended to mean either an indirect or direct electrical or communicative connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices and connections.
[0032] Within the different types of devices wherein the invention may be utilized, such as laptop or desktop computers, hand held devices with processors or processing logic, USB storage key and external hard Drive, and also possibly computer servers or other devices that utilize the invention, there exist different types of memory devices for storing and retrieving information while performing functions according to the invention. Cache memory devices are often included in such computers for use by the central processing unit as a convenient storage location for information that is frequently stored and retrieved. Similarly, a persistent memory is also frequently used with such computers for maintaining information that is frequently retrieved by the central processing unit, but that is not often altered within the persistent memory, unlike the cache memory. As described above in reference to the figures, components included for storing and retrieving larger amounts of information such as data and software applications configured to perform functions according to the invention when executed by a central processing unit. These memory devices may be configured as random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), flash memory, and other memory storage devices that may be accessed by a central processing unit to store and retrieve information. During data storage and retrieval operations, these memory devices are transformed to have different states, such as different electrical charges, different magnetic polarity, and the like. Thus, systems and methods configured according to the invention as described herein enable the physical transformation of these memory devices. Accordingly, the invention as described herein is directed to novel and useful systems and methods that, in one or more embodiments, are able to transform the memory device into a different state. The invention is not limited to any particular type of memory device, or any commonly used protocol for storing and retrieving information to and from these memory devices, respectively.
[0033] The term “machine-readable medium” or similar language should be taken to include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) that store the one or more sets of instructions. The term “machine-readable medium” shall also be taken to include any medium that is capable of storing, encoding or carrying a set of instructions for execution by the machine and that causes the machine to perform any one or more of the methodologies of the invention. The machine-readable medium includes any mechanism that provides (i.e., stores and/or transmits) information in a form readable by a machine (e.g., a computer, PDA, cellular telephone, etc.). For example, a machine-readable medium includes memory (such as described above); magnetic disk storage media; optical storage media; flash memory devices; biological electrical, mechanical systems; electrical, optical, acoustical or other form of propagated signals (e.g., carrier waves, infrared signals, digital signals, etc.). The device or machine-readable medium may include a micro-electromechanical system (MEMS), nanotechnology devices, organic, holographic, solid-state memory device and/or a rotating magnetic or optical disk. The device or machine-readable medium may be distributed when partitions of instructions have been separated into different machines, such as across an interconnection of computers or as different virtual machines.
[0034] While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative of and not restrictive on the broad invention, and that this invention not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.
[0035] Reference in the specification to “an embodiment,” “one embodiment,” “some embodiments,” or “other embodiments” means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least some embodiments, but not necessarily all embodiments. The various appearances “an embodiment,” “one embodiment,” or “some embodiments” are not necessarily all referring to the same embodiments. If the specification states a component, feature, structure, or characteristic “may”, “might”, or “could” be included, that particular component, feature, structure, or characteristic is not required to be included. If the specification or claim refers to “a” or “an” element, that does not mean there is only one of the element. If the specification or claims refer to “an additional” element, that does not preclude there being more than one of the additional element.
[0036] The apparatus and method include a method and apparatus for enabling the invention. Although this embodiment is described and illustrated in the context of devices, systems and related methods of storing data, the scope of the invention extends to other applications where such functions are useful. Furthermore, while the foregoing description has been with reference to particular embodiments of the invention, it will be appreciated that these are only illustrative of the invention and that changes may be made to those embodiments without departing from the principles, the spirit and scope of the invention, the scope of which is defined by the appended claims, their equivalents, and also later submitted claims and their equivalents.
[0037] Although the invention has been particularly described with reference to embodiments thereof, it should be readily apparent to those of ordinary skill in the art that various changes, modifications and substitutes are intended within the form and details thereof, without departing from the spirit and scope of the invention. Accordingly, it will be appreciated that in numerous instances some features of the invention will be employed without a corresponding use of other features. Further, those skilled in the art will understand that variations can be made in the number and arrangement of components illustrated in the above figures. It is intended that the scope of the appended claims include such changes and modifications. | More and more personal or confidential information is stored in storage devices such as but not limited to, laptops, cell phones or USB keys, which are mobile per essence. Due to their mobility, such devices tend to be left unattended or even be lost, compromising the security of the data. This invention is a method to prevent access to the data on a mobile storage device when the intended recipient or user is not in closed range. The invention relies on the use of wireless communication protocol such as but not limited to RF, Bluetooth or Wi-fi to pair a security device with the storage device to enable its functionality. When the security device is not in communication range of the storage device, the data is made inaccessible. A data storage device may include a wireless communication interface used to secure the data, wherein the data storage is partitioned, with each partition having a different security profile. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to control equipment and, more particularly, to electronic and electrical control equipment for use with a laser beam ground leveling device.
Laser beam ground leveling equipment, that is presently available for leveling agricultural fields and the like, utilizes a laser beam transmitter set up in a field at a selected location and a laser beam receiver that is mounted on a conventional box blade type of scraper towed behind a conventional powered tractor. The laser beam, when received by the receiver, actuates controls in the cab of the tractor that raise and lower the box blade relative to an established grade level.
Presently available laser beam control equipment, however, require that frequently the box blade be controlled manually from the tractor cab while the operator of the tractor steers it over the field along prescribed paths. Thus, the tractor operator has too many things to do to perform leveling work efficiently. It is a prime object of the present invention to eliminate manual operation of the box blade by making the operation of the box blade automatic.
The manner in which the present invention electrically and automatically controls the box blade so that there is no gouging and no undesirable dumping of earth from the box blade will become clear to those of ordinary skill in the art from the following description and drawing of a practical example of the invention.
SUMMARY OF THE INVENTION
The present invention provides an electronic and electrical automatic control system for laser beam ground leveling equipment, a portion of which is mounted on a conventional box blade, and a portion of which is mounted in the cab of a tractor drawing the box blade, interconnected with a conventional laser beam ground leveling control. The invention permits to control the raising and lowering of the box blade to effect leveling the ground to a desired grade level without having to operate the conventional box blade controls manually. The present invention permits to actuate the box blade entirely automatically when so desired.
For a further description of the present invention and for features and advantages of it, reference may be had to the following description and drawing representing an example of practical embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWING
In the drawing:
FIG. 1 is a schematic view of a ground leveling operation laser beam effected by means of a tractor-drawn box blade equipped with laser beam control equipment and the control system of the present invention;
FIG. 2 is a schematic enlarged view of the box blade showing some of the controls of the present invention applied thereto; and
FIG. 3 is a schematic wiring diagram of the control of the present invention interconnected with a conventional laser beam earth leveling control.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, a plot of ground 11 has both high areas 13 and low areas 15 that are above and below a desired grade level 17. A tripod-supported pole 19 carries at its top a rotating laser beam transmitter 21 that radiates a narrow laser beam which is received by a laser beam receiver 23 mounted atop a pole 24 affixed adjustably to a conventional box blade 25.
Initially the laser beam transmitter 21 is set on the ground at a height "D" above the desired grade level 17. The ground 11 has the usual high areas 13 and the low areas 15 that have to be reduced and filled respectively to achieve the desired grade level 17.
The box blade 25 is attached to and towed behind a conventional powered tractor 27 in the cab of which are conventional laser beam actuated leveling controls that are operated both automatically and manually. Electrical lead wires 26 connect the laser beam receiver with the laser beam control equipment in the cab of the tractor 27.
Referring to FIG. 2, a schematic view of the box blade 25 is shown with a side plate removed for clarification purposes. The other side plate 29 is fixed to a curved scraper blade 31 to which is mounted pivotally, as at 33, one end of a yoke-carriage 35. The other end of the yoke-carriage 35 is supported by a plurality of rubber tired wheels 37.
The box blade 25 is affixed, as at 39, to another yoke support or drawbar 41 that is attached to the rear of the tractor 27 by a conventional ball and socket arrangement or the like, not shown. Depending from the yoke support 41 is a vertical plate 43 to which is attached the clevis end 44 of a fluid actuated jack in the form of a double acting piston and cylinder assembly 45. The cylinder end portion of the assembly 45 is pivotally connected to a bracket 49 fixed to the yoke-carriage 35, about where shown in FIG. 2. A three-way electrically operated valve 50 is arranged to controllably introduce pressurized fluid to one side or the other of the piston in the piston and cylinder assembly 45 to raise or lower the scraper blade 31.
Mounted also on the yoke-carriage 35 is a level sensor, such as a mercury switch or a mechanical switch 53 that is adjustable.
The three-way valve 50 is operated through a multiconductor electrical cable 51 from a laser control unit mounted in the cab of the tractor 27. The scraper blade 31 is raised when the overall length of the piston and cylinder assembly 45 is lengthened, simultaneously increasing the angle, relative to the ground 17, of the yoke-carriage 35.
The yoke support 41 includes a transverse beam 55 to which is preferably adjustably attached, in any convenient manner, a tubular member 57. The tubular member 57 is angled downwardly, as shown at FIG. 2, and one end of the tubular member carries a fill sensor 59, that is a conventional photoelectric cell. The fill sensor 59 can take any other convenient form indicating filling of the box blade 25 to a predetermined level, such as a mechanical switch, a light beam and light detector, or an infra-red beam and infra-red detector arrangement, for example.
As schematically illustrated at FIG. 3, the level sensor 53 and the fill sensor 59, which are electrically connected in series by a wire 28, are connected, by means of lines 60 and 61, across the pair of inputs 62 and 63 of a control circuit 65.
The control circuit 65, forming the crux of the present invention is preferably mounted, in some convenient location within the cab of the tractor 27, proximate the conventional laser circuit unit 67 to which the laser beam receiver 23 is connected through the electric cable 26. The laser control unit 67, such as, for example, that manufactured and sold by Laser Alignment Co., Inc. of Grand Rapids, Michigan, has a power input connected across the tractor electrical system, not shown, and the usual on and off switch. In addition, the laser control unit 67 has three indicator lights, respectively a red indicator light 69, a green indicator light 71 and a yellow indicator light 73 and three output terminals 74, 75 and 76 labeled respectively "up valve", "down valve" and "down supply". The terminals 74 and 75 are connected to the control wires in the electrical cable 51 connected to the three-way flow control valve 50, FIG. 2, operating the jack 45 for raising or lowering the scraper blade 31. In addition, the laser control unit 67 has a toggle switch 77 capable of occupying a manual and an automatic position. When the switch 77 is placed in the manual position, the action of the laser control unit is inhibited, although the indicator lights 69, 71 and 73 may remain activated. When the toggle switch 77 is thrown to the automatic position, the laser control unit 67 operates the raising and lowering of the scraper blade 31 by way of the control valve 50 through the control cable 51 connecting the laser control unit 67 to the valve 50. When the toggle switch 77 is in the manual position, the lifting and lowering of the scraper blade 31 is controlled directly by the tractor operator by means of the usual manual controls, not shown, in the cab of the tractor 27, such manual controls being directly connected to the valve 50, or to a second valve, not shown, placed in parallel in the hydraulic circuit supplying fluid under pressure to the cylinder piston assembly of the jack 45.
The automatic control unit 65 of the invention, in addition to being connected across the level sensor 53 and the fill sensor 59 through its terminals 62 and 63, is further provided with a pair of input terminals 78 and 79 connected respectively via a line 81 to the grounded chassis of the laser control unit 67, and via a line 82 to a terminal 83 provided on the laser control unit 67. Providing the terminal 83, and two other terminals, 84 and 86, and internally disconnecting the "down supply" from the "down valve" are the only modifications that the present invention require to be incorporated in the laser control unit 67. Terminal 83 is connected internally to one of the contacts of the switch 77 such that the B+ voltage applied to the laser control unit 67 appears at the terminal 83 only when the switch 77 is placed in the automatic position, that is when the laser control unit 67 is energized to be functionally active. Under those conditions, voltage is applied across the terminals 79 and 78 of the control circuit 65. By closing a toggle switch 85, the control circuit 65 is turned on, as indicated by an indicator light 89 connected across the terminals 79 and 78 through the switch 85.
The control circuit 65 is further provided with terminals 74c, 75c, 76c, 84c and 86c which are connected respectively to the terminals 74, 75, 76, 84 and 86 of the laser control unit 67. The terminal 86 is internally connected to a common junction of the red, green and yellow indicator lights 69, 71 and 73 of the laser control unit 67 while the terminal 84 is connected through diodes 87 and 88, respectively, to the other terminal of the green indicator light 71 and the yellow indicator light 73, such that a signal in the form of a voltage is applied to the terminal 84 when either the green light 71 or the yellow light 73 of the laser control unit 67 is turned on. When the laser control unit 67 is in operation, the green indicator light 71 being "on" provides to the operator an indication that grading is effected normally. When the red indicator light 69 turns "on", it provides an indication that grading is being effected at too high a level, namely with the laser beam receiver 23 being positioned above the axis of the laser beam emitted by the transmitter 21, FIG. 1. When the yellow indicator light 73 turns "on", it provides an indication to the operator that grading is being effected at too low a level.
The control circuit 65 comprises a relay 1 having a coil C1 connected across the terminals 78 and 79 through the switch 85. The switch SW1 of the relay 1 is normally closed, thus shunting the terminals 75c and 76c of the control circuit 65 and therefore interconnecting the supply voltage of the laser control unit 67 to the "down valve" command terminal 75. When electrical power is applied to the control circuit 65 the coil C1 of the relay 1 opens the switch SW1, and the terminals 75 and 76 of the laser control unit 67 are no longer interconnected thus allowing the laser control unit 67 to have its action modified by the control circuit 65 as hereinafter explained in further detail.
The control circuit 65 is provided with three indicator lights, a yellow light 90, a green light 91 and a red light 92. A common terminal of the three indicator light 90, 91 and 92 is connected to ground when the control circuit switch 85 is closed. The other terminal of the yellow indicator light 90 is connected through a diode 93 to the terminal 74c of the control circuit, and consequently to the "up valve" terminal 74 of the laser control unit 67. The other terminal of the green indicator light 91 is connected through the normally closed switch SW2 of a relay 2 and through the normally closed switch SW5 of a relay 5 to the terminal 75c of the control circuit 65 and consequently to the "down valve" terminal 75 of the laser circuit unit 67. The other terminal of the red indicator light 92 is connected through the normally closed switch SW3 of a relay 3, through the normally closed switch SW5' of the relay 5 and through the normally closed switch SW4' of a relay 4 to the terminal 74c of the control circuit 65, via a diode 93. The sole function of the relay 2 is to turn off the green indicator light 91 when the red indicator light 92 is on, therefore causing the coil C2 of the relay 2 to open the switch SW2 of the relay 2. The function of the relay 3 is to turn off the red indicator light 92 when the yellow indicator light 90 comes on, therefore causing the coil C3 of the relay 3 to be energized, opening the switch SW3 of the relay 3.
The relay 4 has a normally open switch SW4 and a coil C4 which is in the series circuit of the level sensor 53 and fill sensor 59, which each consists of a normally closed switch. The fill sensor 59 and the level sensor 53 being normally closed switches, when power is applied to the control circuit 65, current flows through the coil C4 of the relay 4. The switch SW4 of the relay 4 closes, thus placing the terminal 75c of the control circuit 65 in connection with the terminal 76c, thus in turn connecting the "down valve" control terminal 75 to the "down supply" terminal 76, with the result that the scraper blade 31 is commanded, FIG. 2, downwardly such as to take the bigger bite in the ground. At the same time, the switch SW4' opens the circuit of the yellow indicator light 90 and closes the circuit of the green indicator light 91.
When the fill sensor 59 becomes covered with earth being scraped by the scraper blade 31, ambient light no longer reaches the photocell of the fill sensor 59, and the photocell no longer conducts electricity. The fill sensor 59 having become an open switch, the "down valve" control terminal 75 of the laser control unit 67 is no longer connected to the supply terminal 76, with the result that the scraper blade 31, FIG. 2, is commanded upwardly. Similarly, when the angle of the yoke-carriage 35 pivotally connecting the box blade 25 to the wheels 37 exceeds the angle limit for which the level sensor 53 has been set, the circuit of the level sensor 53 and fill sensor 59 opens, and the wheels 37 of the scraper blade 31 are commanded downwardly. The level sensor 53 has for its principal purpose to prevent the wheels 37 to come off the ground too high. When traveling over hard ground, for example, it often happens that the scraper blade 31 does not cut deep enough and the wheels 37 come up off the ground. Under the normal control of the laser beam control unit 67, because the box blade has been displaced upwardly, and consequently the laser beam receiver 23 has been displaced upwardly relative to the level of the laser beam, automatic control of the piston and cylinder assembly 45 causes the wheels 37 to continuously raise up, with the result that the scraper digs heavily into the ground. Because the wheels have been raised very high in the air, they can not be returned by the piston and cylinder assembly 45 to a normal position fast enough to prevent the scraper blade 31 from digging a substantially deep hole in the ground.
The control circuit 65 of the invention further comprises a relay 5 having a coil C5 connected across the terminals 86c and 84c, and therefore across the terminals 86 and 84 of the laser control unit 67. Consequently, the relay 5 is activated any time either the green indicator light 71 or the yellow indicator light 73 of the laser control unit 67 is on. When the relay 5 is activated, it opens its normally closed switches SW5 and SW5'. The opening of the switch SW5 turns off the green indicator light 91, which results in turning on the red indicator light 92. The opening of the switch SW5' commands the scraper blade 31 downwardly, unless the fill sensor 59 or the level sensor 53 is open, thus preventing the box blade 25 from coming down. The invention, therefore, permits to remedy one of the shortcomings of the conventional laser control system resulting from the condition present when the box blade 25 is at a high spot in the field that causes the laser beam receiver 23 to be out of range, as being too high, which causes the laser alignment system to become inoperative. When the laser control system becomes inoperative, the operation of the box blade 25 has to be effected, for example lowered, manually. With the present invention, when the laser beam receiver 23 is too high, the relay 5 of the control circuit 65 lowers the box blade 25 automatically.
In a typical operative situation, wherein a field of ground is to be leveled to some arbitrary grade level 17, FIGS. 1 and 2, the box blade 25 is initially empty and may be brought down to ground level by operating the piston and cylinder assembly 45. The tractor 27 draws the box blade 25 over the preselected area of the field to be leveled, such field having high areas 13 and low areas 15 relative to grade level 17. The conventional laser control unit 67, FIG. 3, in the cab of the tractor 27 is activated and the control circuit 65 of the present invention is also activated.
Assuming at first that the box blade 25 is set adjacent a high area 13 and the tractor 27 commences to draw the box blade 25 over the high area 13, the box blade 25 begins to fill with earth until it is full, but the conventional laser beam control equipment would not indicate when the box blade 25 is full of earth. Without the improvement of the invention, when the box blade 25 becomes full of earth, the wheels 37 start to raise up from the ground and the tractor begins to bog down. Therefore, the tractor operator is required to manually override the laser control unit 67 and to operate the box blade 25 through the manual controls in the tractor cab. The box blade 25 is then raised and excess earth drops from the box blade.
As soon as enough earth has been dumped from the box blade 25, the tractor operator reactivates the laser beam control unit 67. When the box blade 25 again becomes full of earth, the tractor operator must again operate the conventional controls manually. It is apparent that the tractor operator must be alert to operate the controls manually while steering the tractor over the prescribed path in the field, and to switch from manual to automatic control as required. When the box blade 25 overfills, the operator is forced to find a low area 15 in the field where the excess earth can be dumped. The operator must ever be alert for overfilling of the box blade, in which situation the operator must revert to manual control. Because most fields are not level, the box blade will be filled continually and the operator of the tractor must work the controls manually a great deal of the total time spent in leveling the field.
In contrast to the way the conventional laser beam control equipment operates, the present invention controls filling and dumping of the fill box or box blade 25 automatically and without operating the manual controls, as long as the conventional laser beam control unit 67 is on automatic position, and prevents overfilling and bogging down of the box blade 25.
When the box blade fills with earth so that the earth covers the photoelectric cell fill sensor 59, as shown at FIG. 2, the controls of the present invention override the conventional laser beam controls and equipment, and the box blade 25 raises and starts to dump some of the earth, thereby exposing the photoelectric fill sensor 59 to daylight.
The mercury or mechanical switch forming the level sensor 53 prevents the wheels 37 from going up too high and causing digging into deep, thus eliminating one of the inconveniences of the conventional laser beam control system.
In a situation wherein the box blade 25 is on a very high area of the field, relatively speaking, the conventional laser beam control equipment continues to command the scraper blade 31 to dig in. The wheels 37 come up off the ground and the tractor bogs down as the box blade 25 becomes overfilled. The improvement of the present invention prevents digging in and overfilling of the box blade 25 because as soon as the circuit including the level sensor 53 and the fill sensor 59 is broken, some earth is dumped by the raising of the box blade 25.
When the red indicating light 92 turns on, it indicates that the box blade 25 is being lowered to grade after dumping some earth. When the box blade 25 reaches grade level, the red indicating light 92 goes off and as soon as the green light 91 comes on, the conventional laser beam control unit 67 takes over.
When the green light 71 of the laser control unit 67 is "on", it indicates that the box blade 25 is on grade with the laser beam receiver 23 receiving the beam emitted by the laser beam transmitter 21. When the yellow light 73 of the laser control unit 67 is "on", it indicates that the box blade 25 is below level. In both those conditions, either when working at grade level or working below grade level, down movement of the scraper blade 31 which will result in scraping more earth should ideally be avoided. Because the relay 5 is switched "on" any time the green indicator light 71 or the yellow indicator light 73 is "on", any down movement of the blade box 25 is prevented, as previously mentioned. | In combination with a conventional laser beam control system for controlling an earth scraping and storing apparatus, such as a box blade for example, for leveling terrain, an improvement detecting when the box blade is full and overflowing is imminent and sensing the level of the box blade relative to the ground. The improvement overrides the functions of the conventional laser beam controls, when desirable, whereby overfilling and bogging down of the box blade is prevented and whereby rough terrain is readily and effectively leveled. | 4 |
RELATED PATENT APPLICATION
This is a division of Ser. No. 08/930,228, filed Jan. 12, 1998, now U.S. Pat. No. 6,144,300, issued Nov. 7, 2000.
BACKGROUND OF THE INVENTION
This invention relates to the exploitation of magnetic properties in a range of practical techniques, and utilizes a new technique of spatial magnetic interrogation in conjunction with a magnetic marker or identification tag. More particularly, but not exclusively, the invention relates to methods of determining the presence and/or the location of a magnetic marker or tag within an interrogation zone; to methods of identifying a magnetic tag (e.g. identifying a given tag in order to discriminate that tag from others); to systems for putting these methods into practice; to magnetic tags for use in such methods and systems; and to the storage of data in such tags, and the subsequent remote retrieval of data from such tags.
It should be understood that the terms “tag” and “marker” are used herein interchangeably; such devices may be used in many different applications and, depending on the magnetic qualities of the device, may serve to denote (a) the mere presence of the tag (and hence that of an article to which the tag is attached); or (b) the identity of the tag (and hence that of an article to which it is attached); or they may serve to define the precise position of the tag with respect to predetermined coordinates (and hence that of an article to which it is attached); or they may serve to provide access codes (e.g. for entry into secure premises; or for ticketing purposes, e.g. on public transport networks); or they may serve generally to discriminate one article or set of articles from other articles.
In addition, the terms “AC field” and “DC field” are used herein to denote magnetic fields whose characteristics are, respectively, those associated with an electrical conductor carrying an alternating current (AC) or a direct current (DC).
The tags, methods and systems of this invention have a wide variety of applications as indicated above. These include (but are not restricted to) inventory control, ticketing, automated shopping systems, monitoring work-in-progress, security tagging, access control, anti-counterfeiting, and location of objects (in particular the precise positioning of workpieces (e.g. probes in surgery)).
PRIOR ART
There are a number of passive data tag systems currently available. The most widely-used is based on optically-read printed patterns of lines, popularly known as barcodes. The tag element of such systems is very low-cost, being typically just ink and paper. The readers are also relatively low cost, typically employing scanning laser beams. For many major applications the only real drawback to barcodes is the need for line-of-sight between the reader and the tag.
For applications where line-of-sight is not possible, systems not employing optical transmission have been developed. The most popular employ magnetic induction for coupling between the tag and the interrogator electronics. These typically operate with alternating magnetic fields in the frequency range of 50 kHz to 1 MHz, and generally employ integrated electronic circuits (“chips”) to handle receive and transmit functions, and to provide data storage and manipulation. In order to avoid the need for a battery, power for the chip is obtained by rectification of the interrogating signal received by an antenna coil. In order to increase the power transferred, and to provide discrimination against unwanted signals and interference, the coil is usually resonated with a capacitor at the frequency of the interrogation signal carrier frequency. A typical product of this type is the TIRIS system manufactured by Texas Instruments Ltd.
Other multi-bit data tag systems have employed conventional h.f. radio technology, or technologies based on surface acoustic waves or magnetostriction phenomena.
FIELD OF THE INVENTION
The present invention involves, inter alia, the use of a new type of passive data tag system which employs small amounts of very high-permeability magnetic material, and a scanned magnetic field for interrogation. Since the magnetic material can be in the form of a thin foil, wire or film, it can be bonded directly to a substrate, e.g. paper or a plastics material, to form self-supporting tags.
Alternatively, the magnetic material may be incorporated into the structure of an article with which the tag is to be associated; thus a tag may be formed in situ with the article in question by applying the magnetic material to the surface of the article, or by embedding the magnetic material within the body of the article.
The invention exploits magnetic fields which contain a “magnetic null”—this term is used herein to mean a point, line, plane or volume in space at or within which the component of the magnetic field in a given linear direction is zero. The volume in space over which this condition is met can be very small—and this gives rise to certain embodiments of the invention in which precise position is determined. Typically the magnetic null will be extant over a relatively small linear range. It should be understood that, where there is a magnetic null, it is possible (and is often the case) that the magnetic field component in a direction orthogonal to the given linear direction will be substantial. In some embodiments of this invention, such a substantial orthogonal field is desirable.
One way of creating the magnetic null is to employ opposing magnetic field sources. These may be current-carrying coils of wire, or permanent magnets (these being well suited to small-scale systems), or combinations of coil(s) and permanent magnet(s). It is also possible to exploit the magnetic nulls which exist in specific directions when a single coil or permanent magnet is used.
For large scale applications, the magnetic field sources are preferably coils carrying direct current.
The invention also utilizes the relative movement between a magnetic marker and an applied magnetic field in order to effect passage over the marker of the magnetic null. This can be achieved by moving the marker with respect to the applied magnetic field, or by holding the marker in a fixed position while the magnetic field is scanned over it. Generally, the invention exploits the difference between the magnetic behavior of the marker in (i) a zero field (at the magnetic null), and (ii) in a high, generally saturating, magnetic field.
Tags of this Invention
According to one aspect of the present invention, there is provided a magnetic marker or tag which is characterized by carrying a plurality of discrete magnetically active regions in a linear array. The discrete magnetically active regions may be supported on a substrate, e.g. paper or a plastics material, or they may be self-supporting. Alternatively, the magnetic elements may be incorporated directly into or onto articles during manufacture of the articles themselves. This is appropriate, for example, when the articles are goods, e.g. retail goods, which carry the tags for inventory purposes; or when the articles are tickets or security passes.
A tag as defined above can also be formed from a continuous strip of high permeability material, discrete regions of which have their magnetic properties permanently or temporarily modified. It will be appreciated that such a process can begin with a high permeability strip selected regions of which are then treated so as to modify their magnetic properties, generally by removing or reducing their magnetic permeability; or with a strip of high permeability magnetic material accompanied by a magnetizable strip positioned close to the high permeability magnetic material, e.g. overlying it or adjacent to it, selected regions of which are magnetized. In relatively simple embodiments, each magnetically active region has the same magnetic characteristics; in more complex embodiments, each magnetically active region can possess a different magnetic characteristic, thus making it possible to assemble a large number of tags, each with unique magnetic properties and hence with a unique magnetic identity and signature (when processed by a suitable reader device).
Because the invention utilizes relative movement between a tag and an applied magnetic field, it will be appreciated that there will be a correspondence between the time domain of output signals from a tag reading device and the linear dimensions of the magnetically active regions of a tag and of the gaps between the magnetically active regions. In this sense, the active regions and the gaps between them function analogously to the elements of an optical bar code (black bar or white gap between adjacent bars). It follows from this that, just as variability of magnetic characteristics in the active regions can be used to generate part of a tag “identity”, so can the linear spacing between adjacent magnetically active regions. It will readily be understood that a vast number of tags, each with its own unique identity, can thus be produced in accordance with this invention.
Although the tags have been described as possessing a linear array of magnetically active regions, the tags may in fact have two or more such linear arrays. These may be disposed mutually parallel, or mutually orthogonal, or in any desired geometrical arrangement. For simplicity of reading such tags, arrays which are parallel and/or orthogonal are preferred.
Appropriate techniques for manufacturing the tags of this invention are well-known in conventional label (i.e. magnetic marker) manufacture. Suitable magnetic materials are also well-known and widely available; they are high-permeability materials which preferably have an extrinsic relative permeability of at least 10 3 . The coercivity of the magnetic material will depend on the tag's intended use. The magnetic material is preferably in the form of a long thin strip or of a thin film; these formats avoid major internal demagnetization effects. Suitable strip materials are readily available from commercial suppliers such as Vacuumschmeltze (Germany), Allied Signal Corp. (USA), and Unitika (Japan). Thin film material currently manufactured in high volume by IST (Belgium) for retail security tag applications is also suitable for use in this invention.
Detection/Identification Methods
As well as the tags defined above, the present invention provides a variety of useful methods for detecting the presence of a magnetic marker and/or for identifying such a marker. While in many cases these methods will be intended for use in conjunction with the tags of the invention, this is not a necessary prerequisite in the methods of the invention.
According to a second aspect of the invention, there is provided a method of interrogating a magnetic tag or marker within a predetermined interrogation zone, the tag comprising a high permeability magnetic material, for example to read data stored magnetically in the tag or to use the response of the tag to detect its presence and/or to determine its position within the interrogation zone, characterized in that the interrogation process includes the step of subjecting the tag sequentially to: (1) a magnetic field sufficient in field strength to saturate the high permeability magnetic material, and (2) a magnetic null as herein defined.
Preferably the magnetic null is caused to sweep back and forth over a predetermined region within the interrogation zone. The scanning frequency (i.e. the sweep frequency of the magnetic null) is preferably relatively low, e.g. 1-500 Hz. Conveniently, the field pattern is arranged so that (a) said magnetic null lies in a plane; and (b) the saturating field occurs adjacent to said plane.
According to a third aspect of this invention, there is provided a method of determining the presence and/or the position of a magnetic element within a predetermined interrogation zone, the magnetic element having predetermined magnetic characteristics, which method is characterized by the steps of: (1) establishing within said interrogation zone a magnetic field pattern which comprises a relatively small region of zero magnetic field (a magnetic null) contiguous with regions where there is a magnetic field sufficient to saturate the, or a part of the, magnetic element (the saturating field), said relatively small region being coincident with a region through which the magnetic element is passing, or can pass, or is expected to pass; (2) causing relative movement between said magnetic field and said magnetic element such that said magnetic null is caused to traverse at least a part of the magnetic element in a predetermined manner; and (3) detecting the resultant magnetic response of the magnetic element during said relative movement.
According to a fourth aspect of the present invention, there is provided a method of identifying a magnetic element which possesses predetermined magnetic characteristics, which method is characterized by the steps of: (1) subjecting the magnetic element to a first magnetic field which is sufficient to induce magnetic saturation in at least a part of the magnetic element; (2) next subjecting the magnetic element to conditions of zero magnetic field (i.e. a magnetic null), the zero field occupying a relatively small volume and being contiguous with said first magnetic field; (3) causing relative movement between the applied magnetic field and said magnetic element such that said magnetic null is caused to traverse at least a part of the magnetic element in a predetermined manner; and (4) detecting the resultant magnetic response of the magnetic element during said relative movement.
In the identification method defined above, the magnetic element is advantageously caused to traverse an interrogation zone within which the required magnetic conditions are generated.
In a fifth aspect, the invention provides a method of identifying a magnetic element, the magnetic element having predetermined magnetic characteristics, which method is characterized by the steps of: (1) causing the magnetic element to enter an interrogation zone within which there is established a magnetic field pattern which comprises a relatively small region of zero magnetic field (a magnetic null) contiguous with regions where there is a magnetic field sufficient to saturate the, or a part of the, magnetic element (the saturating field); (2) causing the magnetic element to be moved through the saturating field until it reaches the magnetic null; (3) causing relative movement between said magnetic field and said magnetic element such that said magnetic null is caused to traverse at least a part of the magnetic element in a predetermined manner; and (4) detecting the resultant magnetic response of the magnetic element during said relative movement.
The relative movement between the magnetic element and the magnetic field may advantageously be produced by sweeping the applied magnetic field over the magnetic element. Alternatively, the relative movement can be achieved by the application of an alternating magnetic field to a generally static magnetic field pattern.
In carrying out the methods defined above, preferred embodiments of the magnetic element are either elongate, and the magnetic null is then arranged to extend along the major axis of said magnetic element; or they are in the form of a thin film, in which case the magnetic null is arranged to extend to be aligned with the axis of magnetic sensitivity of the thin film material.
The magnetic field or field pattern utilized in the methods defined above may be established by the means of two magnetic fields of opposite polarity. This can conveniently be achieved by use of one or more coils carrying direct current; or by the use of one or more permanent magnets; or by a combination of coil(s) and magnet(s).
Where a coil is used, it may be arranged to carry a substantially constant current so as to maintain the magnetic null at a fixed point. Alternatively, the coil(s) carry/carries a current whose magnitude varies in a predetermined cycle so that the position of the magnetic null is caused to oscillate in a predetermined manner. We describe this as a “flying null’. A similar arrangement can be used to give a flying null when both a coil or coils and a permanent magnet are used.
According to a further aspect of the present invention, there is provided a method of determining the presence and/or the position of a magnetic element, which is characterized by the steps of: (1) applying a magnetic field to a region where the magnetic element is, or is expected to be, located, said magnetic field comprising two opposed field components, generated by magnetic field sources, which result in a null field (a magnetic null) at a position intermediate said magnetic field sources (which position is known or can be calculated); (2) causing relative movement between said magnetic field and said magnetic element; and (3) detecting the resultant magnetic response of the magnetic element during said relative movement.
Relative movement between the magnetic field and the magnetic element may be achieved by applying a relatively low amplitude alternating magnetic field superimposed on the DC field. Typically, such a low amplitude alternating magnetic field has a frequency in the range from 10 Hz to 100 kHz, preferably from 50 Hz to 50 kHz, and most advantageously from 500 Hz to 5 kHz.
In one embodiment, the coils carry a substantially constant current so as to maintain the magnetic null at a fixed point. In another embodiment, the coils carry a current whose amplitude varies in a predetermined cycle so that the position of the magnetic null is caused to oscillate in a predetermined manner.
In the methods according to this invention, detection of the magnetic response of the magnetic element advantageously comprises observation of harmonics of the applied AC field which are generated by the magnetic element as its magnetization state is altered by passing through the magnetic null.
As indicated above, the system operates with a zero or very low frequency scanning field, and an HF (high frequency) in the range 50 Hz-50 kHz. This allows for good signal penetration through most materials including thin metal foils. In addition, international regulations allow high fields for transmission at these low frequencies.
Preferred embodiments of the invention provide a multi-bit data tag system which employs low-frequency inductive magnetic interrogation, and avoids the need for complex, expensive tags.
According to another aspect of the present invention, there is provided a method of coding and/or labeling individual articles within a predetermined set of articles by means of data characteristic of the articles, e.g. article price and/or the nature of the goods constituting the articles, which method is characterized by applying to each article a magnetic tag or marker carrying a predetermined arrangement of magnetic zones unique to that article or to that article and others sharing the same characteristic, e.g. article price or the nature of the goods constituting the article, said magnetic tag or marker being susceptible to interrogation by an applied magnetic field to generate a response indicative of the magnetic properties of the tag or marker and hence indicative of the nature of the article carrying the magnetic tag or marker.
Fundamentals of the Invention
Before describing further embodiments, it will be helpful to explain some fundamental aspects of the invention, giving reference where appropriate to relatively simple embodiments.
A key aspect of the invention is the form of the magnetic field created in the interrogation zone; as will become apparent later, this field allows very small spatial regions to be interrogated. The means for generating this magnetic field will be termed hereinafter an “interrogator”. In one simple form, the interrogator consists of a pair of closely-spaced identical coils arranged with their axes coincident. The coils are connected together such that their winding directions are opposed in sense, and a DC current is passed through them. This causes opposing magnetic fields to be set up on the coils' axis, such that a position of zero field—a magnetic null—is created along the coil axis, mid-way between the coils. The level of current in the coils is such as to heavily saturate a small sample of high permeability magnetic material placed at the center of either of the two coils. A much lower amplitude AC current is also caused to flow in opposite directions through the two coils, so that the AC fields produced sum together midway between the coils. This can easily be arranged by connecting a suitable current source to the junction of the two coils, with a ground return. The frequency of this AC current may typically be about 2 kHz, but its value is not critical, and suitable frequencies extend over a wide range. This AC current generates the interrogating field which interacts with a magnetic tag to generate a detectable response. Another effect of this AC current is to cause the position of zero field—the magnetic null—to oscillate about the mid-way position along the coils' axis by a small amount (this is a wobble or oscillation rather than an excursion of any significant extent).
In addition, a further, low frequency AC current may be fed to the coils so as to generate a low frequency scanning field (which may be zero). The frequency of the scanning field (when present) should be sufficiently low to allow many cycles of the relatively high frequency interrogation field to occur in the time that the magnetic null region passes over the tag; typically, the frequency ratio of interrogating field (ω c ) to the scanning field (ω b ) is of the order of 100:1, although it will be appreciated that this ratio can vary over a considerable range without there being any deleterious effect on the performance of the invention.
When a tag containing a piece of high-permeability magnetic material is passed along the coils' axis through the region over which oscillation of the magnetic zero plane occurs, it will initially be completely saturated by the DC magnetic field. It will next briefly be driven over its B-H loop as it passes through the zero field region. Finally it will become saturated again. The region over which the magnetic material is “active”, i.e. is undergoing magnetic changes, will be physically small, and is determined by the amplitude of the DC field, the amplitude of the AC field, and the characteristics of the magnetic material. This region can easily be less than 1 mm in extent. If the level of the alternating field is well below that required to saturate the magnetic material in the tag, then harmonics of the AC signal will be generated by the tag as it enters the zero field region of interrogator field and responds to the changing field. As the tag straddles the narrow zero field region the tag will be driven on the linear part of its B-H loop, and will interact by re-radiating only the fundamental interrogation frequency. Then, as the tag leaves the zero field region, it will again emit harmonics of the interrogation field frequency. A receiver coil arranged to be sensitive to fields produced at the zero field region, but which does not couple directly to the interrogator coils, will receive only these signals. The variation of these signals with time as the tag passes along the coils axis gives a clear indication of the passage of the ends of the magnetic material through the zero field region.
It will be appreciated that because the interrogation zone can be very narrow, each individual piece of magnetic material can be distinguished from its neighbors, from which it is separated by a small distance. Naturally, the magnetic material will be selected to suit the particular application for which the tag is intended. Suitable magnetic materials are commercially available, as described hereinbefore.
If a tag containing a number of zones or pieces of magnetic material placed along the axis of the label is now considered, it will be appreciated that as each zone or piece of magnetic material passes through the zero-field region, its presence and the positions of its ends can be detected. It then becomes a simple matter to use the lengths and spacing of individual zones or pieces of magnetic material to represent particular code sequences. Many different coding schemes are possible: one efficient arrangement is to use an analogue of the coding scheme used for optical barcodes, where data is represented by the spacing and widths of the lines in the code.
The system so far described allows for the scanning of a single-axis tag (e.g. a wire or a thin strip of anisotropic material, having a magnetic axis along its length) as it physically moves through the coil assembly. It will be appreciated that relative movement between the tag and the interrogating field can be achieved either with the field stationary and the tag moving, or vice versa. If required, the arrangement can be made self-scanning, and thus able to interrogate a stationary tag, e.g. by modulating the d.c. drive currents to the two interrogator coils, so that the zero field region scans over an appropriate portion of the axis of the coils. The extent of this oscillation needs to be a: least equal to the maximum dimension of a tag, and should preferably be considerably greater, to avoid the need for precise tag positioning within the interrogation zone.
By using extra coils arranged on the 2 axes orthogonal to the original, tags in random orientations can be read by sequentially field scanning. This involves much greater complexity in the correlation of signals from the three planes, but because of the very high spatial resolution available would be capable of reading many tags simultaneously present in a common interrogation volume. This is of enormous benefit for applications such as tagging everyday retail shopping items, and, for example, would allow automated price totalization of a bag of shopping at the point of sale. Thus the invention has applicability to the price labeling of articles and to point-of-sale systems which generate a sales total (with or without accompanying inventory-related data processing)
The size of a simple linear tag is dependent on the length of the individual elements, their spacing and the number of data bits required. Using strips of the highest permeability material commercially available, such as the “spin-melt” alloy foils available from suppliers such as Vacuumschmeltze (Germany) and Allied Signal (USA), the minimum length of individual elements which can be used is probably of the order of a few millimeters. This is because the extrinsic permeability will be dominated by shape factors rather than by the very high intrinsic permeability (typically 10 5 ), and shorter lengths may have insufficient permeability for satisfactory operation.
For this reason it is attractive to use very thin films of high permeability magnetic material. Provided it is very thin, (ideally less than 1 μm), such material can be cut into small 2 dimensional pieces (squares, discs, etc.) with areas of just 20 mm 2 or less, yet still retain high permeability. This will enable shorter tags than possible with elements made from commercially available high-permeability foils. Suitable thin film materials are available commercially from IST (Belgium).
An extension to this type of programming can also be used to prevent the composite tag producing an alarm in a retail security system (such an alarm would be a false indication of theft, and would thus be an embarrassment both to the retailer and to the purchaser). If different regions of the tag are biased with different static field levels, they will produce signals at different times when they pass through retail security systems. This will complicate the label signature in such systems and prevent an alarm being caused. In the present invention, the reading system will be able to handle the time-shifted signals caused by such magnetic biasing.
Thus far tag coding has been described on the basis of physically separated magnetic elements. It is not essential, however, to physically separate the elements; programming of data onto a tag may be accomplished by destroying the high-permeability properties of a continuous magnetic element in selected regions thereof. This can be done, for example, by local heating to above the re-crystallization temperature of the amorphous alloy, or by stamping or otherwise working the material. Of even more importance is the ability to magnetically isolate regions of a continuous element of high permeability material by means of a magnetic pattern stored on an adjacent bias element made from medium or high coercivity magnetic material. Such a composite tag could then be simply coded by writing a magnetic pattern onto the bias element using a suitable magnetic recording head. If required, the tag could then be erased (by de-gaussing with an AC field) and re-programmed with new data.
The scheme described can also be extended to operate with tags storing data in two dimensions. This allows for much more compact tags, since as well as being a more convenient form, a tag made up from an N×N array of thin-film patches has much more coding potential than a linear array of the same number of patches. This is because there are many more unique patch inter-relationships that can be set up in a given area.
FURTHER EMBODIMENTS
Use of Spatial Magnetic Scanning for Position Sensing
In addition to interrogating space to read data tags, this new technique of moving planes of zero field through space (or moving things through the planes) can be used to provide accurate location information for small items of high permeability magnetic material.
Thus, according to another aspect, the invention provides a method of determining the precise location of an object, characterized in that the method comprises: (a) securing to the object a small piece of a magnetic material which is of high magnetic permeability; (b) applying to the region in which said object is located a magnetic field comprising two opposed field components, generated by magnetic field sources, which result in a null field at a position intermediate said magnetic field sources; (c) applying a low amplitude, high frequency interrogating field to said region; (d) causing the position of the null field to sweep slowly back and forth over a predetermined range of movement; (e) observing the magnetic interaction between said applied magnetic field and said small piece of magnetic material; and (f) calculating the position of the object from a consideration of said magnetic interaction and from the known magnetic parameters relating to said applied field and to said small piece of magnetic material. Advantageously, the small piece of high permeability magnetic material is in the form of a thin foil, a wire or a thin film.
This aspect of the invention is of particular interest when the object whose location is to be determined is a surgical instrument, for example a surgical probe or needle. The invention allows precise determination of the location of, for example, a surgical probe during an operation.
This technique is ideal for accurate location of very small markers within relatively confined volumes; it can separately resolve multiple markers. It also displays low sensitivity to extraneous metal objects.
The magnetic tag or marker can typically be a 1 cm length (longer if desired) of amorphous wire (non-corrosive, diameter 90 micron or less) similar to that used in EAS tags or, with suitable process development, a short length (e.g. 1 cm) of a needle sputter-coated with a thin layer of soft magnetic material.
In use around the head of a patient, resolution to 0.1 mm with the described markers can be achieved. Accuracy should also have the potential to approach this value if some precautions about calibration and use of other magnetic materials are observed, but for optimum performance a rigid but open structure close to the head would be desired. The magnetic field levels employed will be lower than those generated by everyday magnets (e.g. kitchen door catches, etc.).
This technique has particular application to brain surgery, where there is the requirement to locate the position of probes in three dimensions and with high precision. It is therefore possible, in accordance with this invention, to use small magnetic markers on such probes or needles. In this case, a key advantage is that the signal from the marker need only be detected and resolved in time; the resolution is determined by the location of the zero field plane, not by the signal-to-noise ratio of the detected marker signal. This permits a very small marker to be used.
A single axis position sensor may be implemented with a set of coils similar to the tag reading system described above. This comprises: a pair of opposed coils carrying DC current to generate a DC field gradient; a means of applying a relatively uniform low level AC field to drive the marker in and out of saturation in the small region where the DC field is close to zero; and a means of applying a relatively uniform DC field of variable strength and polarity to move the location of the plane of zero DC field around the volume to be interrogated.
An anisotropic marker—i.e. one having a preferential axis of magnetization—resolves the magnetic field along its length. Such a marker can be obtained, for example, by using a long, thin element of a magnetic material or by suitable treatment of an area of magnetic material having a much lower aspect ratio, e.g. by longitudinally annealing a generally rectangular patch of a spin-melt magnetic material. In the context of the single axis position sensor under discussion there are five degrees of freedom (x, y, z and two angles (rotation of the marker about its axis has no effect)). Three orthogonal complete sets of coils can capture sufficient information by doing three scans of the uniform DC field on each of the sets of coils in turn. The first scan with no field from the other sets, the second with a uniform DC field from one of the other sets, and the third with DC field from the other set. This gives nine scans in all; these may be represented as in the following table, in which the magnetic field sources are identified as a, b and c and the scans are numbered from 1-9 (scanning order being of no significance)
Ortho-
gonal
field
source
1
2
3
4
5
6
7
8
9
a
ON
ON
ON
OFF
OFF
ON
OFF
OFF
ON
b
OFF
ON
OFF
ON
ON
ON
OFF
ON
OFF
c
OFF
OFF
ON
OFF
ON
OFF
ON
ON
ON
The only information required from each scan is the position of the center of the harmonic output from the marker within that scan. These nine DC field values can then be converted into the xyz-theta-phi coordinates of the marker. To start with, the system can simply be used by holding the marker in the desired position before the head is put into the coils; and then when the head is placed in the coils the marker can be moved until the same signals are obtained.
An alternative to sequential interrogation which has the advantage of requiring less time to scan the region of interest is to rotate the magnetic field gradient continuously so as to scan all directions of interest. This can be accomplished by driving three sets of coils with appropriate continuous waveforms. For example, a suitable scanning field will be created if coils in the x, y and z planes are driven with currents I x , I y and I z given by the equations:
I x =cos ω a t(A cos ω b t−sin ω b t.sin ω c t)−sin ω a t.cos ω c t
I y =sin ω a t(A cos ω b t−sin ω b t.sin ω c t)+cos ω a t.cos ω c t
I z =A sin ω b t+cos ω b t.sin ω c t
where: ω a =overall frequency of rotation of applied magnetic field
ω b =null scanning frequency
ω c =interrogation frequency
A=amplitude ratio ω b : ω c .
Typical (but non-limiting) values of these parameters are:
A=10;
frequency ratio ω a :ω b ≅1:10; and
frequency ratio ω b :ω c ≅1:400.
DESCRIPTION OF THE DRAWINGS
The invention will now be illustrated with reference to the accompanying drawings, in which:
FIG. 1 illustrates the fundamental elements of a tag reading system of the invention;
FIG. 2 is a circuit diagram illustrating one mode of generating the desired magnetic field pattern with the arrangement of FIG. 1;
FIG. 3 relates the magnetic response of a tag to its position within the reading system of FIG. 1;
FIG. 4 illustrates where magnetic nulls occur with a permanent magnet;
FIG. 5 illustrates an embodiment of the invention which utilizes a coil and a permanent magnet to generate the desired field pattern;
FIG. 6 illustrates an embodiment of the invention which utilizes a pair of permanent magnets to generate the desired field pattern;
FIG. 7 illustrates an embodiment of the invention which utilizes a plurality of permanent magnets disposed in an annular array with a coil to generate the desired field pattern;
FIG. 8 is a schematic circuit diagram for one embodiment of a tag interrogator in accordance with the invention;
FIG. 9 illustrates a selection of tags in accordance with this invention; and
FIG. 10 illustrates an embodiment of the invention as applied to surgical operations.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Referring to FIG. 1, a schematic arrangement is shown in which a tag 1 is positioned mid-way between two coils Tx 1 and Tx 2 . The tag is of the type shown in FIG. 9 a , i.e. a simple linear tag carrying a plurality of magnetic elements each of which is a high-permeability magnetic alloy material, for example Vacuumschmeltze 6025 spin melt ribbon having an intrinsic permeability of about 10 5 . The reader will appreciate that the values given in this description for the various parameters associated with the elements shown in FIG. 1 are given merely by way of example, and illustrate one working embodiment. The values of these parameters will inevitably vary according to the overall size of the system and its intended function. The magnetic elements which constitute the discrete magnetically active regions of the tag have dimensions 10 mm×1 mm×25 microns; the spacing between adjacent elements is 1 mm. The two coils are spaced apart by approximately 20 cm and each comprise 450 turns of 0.56 mm copper wire wound in a square configuration typically 45 cm×45 cm. Each coil has a resistance of GD and an inductance of 100 mH. Each of the coils Tx 1 and Tx 2 carries a direct current I superimposed upon which is a smaller alternating current i; typically, the direct current I is of the order of 3A while the superimposed alternating current I is of the order of 50 mA. The alternating current i is of relatively high frequency, typically about 2 kHz.
With a system such as that just described, the alternating and direct currents in the two coils generate a magnetic field pattern in which there is a magnetic null in the direction of arrow x at points lying in a plane parallel to the two coils and mid-way between them. In FIG. 1, the x- and y-coordinates of this mid-way plane are represented by the lines 2 and 3 , respectively.
If a magnetic tag of this invention is passed through the two coils shown in FIG. 1, travelling in direction x and generally along the longitudinal axis defined between the center points of the two coils, ft will pass through a magnetic field polarity inversion at the mid-way plane defined by coordinates 2 and 3 . The change in polarity of the magnetic field comes about because the DC current flows in one sense in the first of the coils and in the opposite sense in the other of the coils, as indicated by the bold arrows in FIG. 1 . At the mid-way plane, the magnetic field component generated by the direct current flowing in the first coil exactly cancels the magnetic field component generated by the direct current flowing in the other coil.
As the tag travels through the center of the first coil, it experiences a high magnetic field which is sufficient to saturate its magnetically active elements; as the field strength decreases on moving towards the mid-way plane, the magnetic material is influenced by the decreasing magnetic field in a way dictated by its hysteresis curve. In the vicinity of the magnetic null, the direction of magnetization of the magnetic elements of the tag is reversed.
The relatively high frequency alternating current i shown in FIG. 1 is identical in each of the coils Tx 1 and Tx 2 .
The alternating current can have a frequency within a wide range, as indicated hereinbefore; a typical operating value with the arrangement of FIG. 1 is about 2 kHz. The effect of this relatively low amplitude alternating current is to cause the mid-way plane defined by coordinates 2 , 3 to oscillate about the geometric midpoint along the longitudinal axis defined between the midpoints of the two coils. In other words, the plane containing the magnetic null oscillates or wobbles back and forth over a small spatial region at the frequency of the alternating current.
FIG. 2 shows a simple circuit for providing opposed DC fields combined with AC fields. Capacitor C 1 is selected to resonate with the inductance of coils Tx 1 and Tx 2 at the AC drive frequency; each of these coils has a resistance of 6 ohms and an inductance of 100 millihenries. A typical value for C 1 is 0.1 μF. C 2 is a capacitor selected to behave as an effective short-circuit at the AC drive frequency; a typical value for this component is 22 μF. The DC power supply will typically provide 30 volts at 3 amps; and the AC source will typically deliver an alternating current at a frequency of 2 kHz at 2 v rms.
FIG. 3 illustrates how the magnetization of a single magnetic element varies with time at different positions within the magnetic field pattern defined between the coils Tx 1 and Tx 2 of FIG. 1 . For ease of illustration, the oscillation of the plane containing the magnetic null is represented by the bold double-headed arrow (⇄) 4 , the extreme positions of the plane being represented by dashed lines 5 and 6 , respectively, and the mid-point between limiting planes 5 and 6 being represented by dashed line 7 . In the right hand portion of FIG. 3, the applied AC field is shown varying with time between positive (H+) and negative (H−) field values. Beneath the graph of the applied AC field, there are five graphs depicting how the net magnetization of the magnetic element varies with time in each of five geometric positions indicated to the left as Position 1 , Position 2 , etc. Planes 5 and 6 define the limits of regions within which magnetic field polarity reversals occur. In practice, the separation between planes 5 and 6 is typically of the order of 1 mm; for a given magnetic material, this distance can be increased or decreased at will within certain limits by varying the amplitude of the AC current and/or the DC current in the coils.
At all times, the magnetic element has a linear magnetic axis which is orthogonal to the planes 5 , 6 and 7 .
In Position 1 , the end of the magnetic element is adjacent to plane 6 ; in this condition, it experiences a positive magnetic field at all times and its net magnetization is time-invariant. In Position 2 , the leading end of the element has reached the mid-way plane 7 . Most of the magnetic material, however, still remains outside limiting plane 6 . In consequence, the null plane is able to interact with only a portion of the magnetic material, resulting in a time-variable net magnetization having the repeat pattern shown, i.e. a straight line positive-value portion followed by a generally sinusoidal arc which dips towards zero and then rises to its original positive value.
In Position 3 , the magnetic material is positioned symmetrically with respect to the mid-way plane 7 . Here, the net magnetization versus time plot consists of a sine wave whose frequency corresponds to that of the applied AC field. In Position 4 , the majority of the magnetic element experiences a negative field at all times, while a smaller part of the element experiences polarity reversals; this leads to the net magnetization versus time plot as shown. The fact that Position 4 is in effect the inverse of Position 2 is reflected in the relationship between the magnetization plots for these two positions; as can be seen, the plot for Position 4 is effectively a mirror image of that for Position 2 but with the curved portions time-shifted.
Finally, that Position 5 , all of the tag experiences the negative field, and no part of the tag experiences field polarity reversal. In consequence, the net magnetization is time-invariant, being a constant negative value as shown.
When a tag containing such a magnetic element is passed along the coils' axis through the region of zero field, it will initially be completely saturated by the DC magnetic field. It will next briefly be driven over its B-H loop as it passes through the zero field region. Finally it will become saturated again. The portion of the traverse over which the magnetic material is “active”, i.e. is undergoing magnetic changes, is physically small, and is determined by the amplitude of the DC field, the amplitude of the AC field, and the characteristics of the magnetic material. This region can easily be less than 1 mm in extent. If the level of the alternating field is well below that required to saturate the magnetic material in the tag, then harmonics of the AC signal will be generated by the tag as it enters the zero field region (Positions 1 to 2 ) and responds to the changing field. As the tag straddles the narrow zero field region (Position 3 ) the tag will be driven on the linear part of its B-H loop, and will interact by re-radiating only the fundamental interrogation frequency. Then, as the tag leaves the zero field region, (Positions 4 to 5 ) it will again emit harmonics of the interrogation field frequency.
A receiver (Rx) coil arranged to be sensitive to fields produced at the zero field region, but which does not couple directly to the interrogator (Tx) coils, will receive only these signals. Such an arrangement can be achieved by using separate Tx and Rx coils physically arranged to have low mutual coupling; or by using a single coil (having both Tx and Rx functions) together with suitable filtering in the Tx and Rx paths. The variation of these signals with time as the tag passes along the coils' axis gives a clear indication of the passage of the ends of the magnetic material through the zero field region.
The result of this interaction between the tag and the magnetic field it experiences is shown in FIG. 3 b . Here, the region 4 over which the magnetic null oscillates is shown on a smaller scale, and the numbered dots represent the location of the mid-point of the tag in each of Positions 1 - 5 . The generation of a harmonic signal by the tag (illustrated by the second harmonic of the applied frequency) is apparent at positions where the tag enters the region defined by limiting planes 5 and 6 , i.e. the zone where magnetic field polarity reversals occur. Because of the symmetry of the system, a single magnetic element will generate a doublet peak 8 a and 8 b since Positions 2 and 4 are redundant.
Referring now to FIG. 4, this illustrates the lines of force (i.e. the magnetic contours) existing with a simple bar magnet. The plane X-Y which intersects the longitudinal axis of the bar magnet and which is orthogonal to the plane of the paper constitutes a magnetic null plane. Thus a magnetic element possessing a sensitive magnetic axis aligned orthogonally with respect to the null plane will experience a magnetic null as it traverses either path A-B or path C-D. Consequently a simple bar magnet can be used as part of an interrogation system to detect the presence of such a magnetic tag, or to read information carried by such a tag.
The generation of second harmonic signal can form the basis of a tag detection system. If, instead of just a single magnetic element the tag includes a linear array of n magnetic elements, the second harmonic output from the tag will comprise n duplet peaks, each of the type shown in FIG. 3 b . If the size and magnetic characteristics of the magnetic elements are all the same, the peaks will have the same profile and each peak will define an envelope of constant area. The spacing between individual magnetic elements will influence the relative positions of the duplet peaks on an amplitude versus time plot. It will be appreciated that the present invention is not restricted to the use of such simple tags as just described. The use of magnetic elements of different sizes and magnetic characteristics, and with non-uniform spacing along the length of the magnetic tag, will generate more complex signal patterns which nevertheless are characteristic of the given tag construction. By varying the number, the magnetic characteristics, and the positioning of a series of magnetic elements, it is possible to manufacture a very large number of magnetic tags each with its own unique characteristics which will accordingly generate a unique signal when used in conjunction with the system of FIGS. 1-3.
It will also be appreciated that the invention is not limited to observing the second harmonic of the applied alternating frequency; this particular harmonic has been selected for the purposes of illustration since it is relatively easy to generate a transmit signal (Tx output) which has no (or very little) second harmonic content, thus permitting good discrimination between the Tx signal and the response of the tag; and since it also contains a relatively high proportion of the total harmonic energy output from the tag.
Referring next to FIG. 5, there is shown a schematic arrangement for a simple tag reader in accordance with this invention, the reader utilizing a permanent magnet 10 and a coil 11 located adjacent to one face of the magnet. In this embodiment, a tag which is to be read can be passed along path C-D through coil 11 or along path A-B above the coil. The tags must be oriented with their magnetic axis aligned with the direction of tag movement. In FIG. 5, the magnetic null plane is positioned at 12 as shown.
Referring next to FIG. 6, the use of two permanent magnets positioned with their magnetic axes aligned and with like poles opposing one another is illustrated. Such an arrangement generates a null plane 13 ; the direction of tag motion required is indicated by arrows 14 . Again, the magnetic axis of the tag must be aligned with the direction of movement.
FIG. 7 shows a simple realization of a tag reader head using a plurality of permanent magnets to generate a magnetic null plane. As illustrated ten polymer-bonded ferrite magnets are disposed in an annular array with like poles facing inwards. A common transmit/receive coil L 1 sits within the annulus of magnets in the manner indicated. The tag is read as it passes through the null plane in the center of the loop of magnets.
Referring next to FIG. 8, there is shown one embodiment of an interrogation system in accordance with this invention. This is based on the use of a single coil L 1 to act as both transmitter (Tx) coil, which generates the desired magnetic field pattern, and as the receiver (Rx) coil. The system uses the second harmonic output of the tag as the oasis for tag detection/identification. Circuit components C 1 and L 2 form a resonant trap at frequency 2f to reduce signals at this frequency in the Tx output to a very low level; C 2 resonates with L 1 at frequency f; and components C 3 , C 4 , L 1 and L 3 form a filter to pass wanted signals from the tag at frequency 2f while rejecting signals at the transmitted frequency f.
The output obtained from this circuit passes through a low pass filter to an analogue to digital converter (ADC) and thence to a digital signal processor. These components, and in particular the signal processor, will be configured to suit the intended application of the interrogation unit. The nature of the signal processing, and the means by which it is achieved, are all conventional and therefore will not be described further here.
FIG. 9 illustrates the basic structure of magnetic tags in accordance with the invention. FIG. 9 a shows a tag 100 which comprises a support medium 101 (e.g. paper or a plastics material) and a linear array of magnetically active regions 102 , 103 , 104 , 105 and 106 . Each magnetically active region is formed from a patch of high-permeability magnetic material (e.g. Vacuumschmeltze 6025) having its magnetic axis aligned along the length of the tag. Each patch is about 10 mm 2 in area and is adhesively secured to the substrate 101 .
Patches 102 - 105 are identical in dimensions and magnetic properties, and are uniformly spaced apart, gaps 110 , 111 and 112 all being the same. The gap between patches 105 and 106 , however, is larger—as though there were one patch missing at the position indicated by dotted lines at 113 .
Tag 100 behaves as a six-bit tag, coded 111101 (the zero being area 113 ).
A functionally equivalent tag 120 is formed of a substrate 121 carrying magnetic elements 122 - 126 and having a “gap” 127 ; in this embodiment, the magnetic elements are in the form of a strip or wire of high-permeability magnetic material (e.g. Vacuumschmeltze 6025), typically being about 5 mm long, 1 mm wide and about 15 microns in thickness.
FIG. 9 b illustrates an alternative construction for a six-bit, laminated tag 130 . This tag is coded 111101, as in FIG. 9 a . Here, a continuous layer or length of high permeability magnetic material 131 (in the form of wire, strip, thin film or foil) and a substrate 133 have sandwiched between them a magnetic bias layer 132 . The bias layer is magnetized in predetermined areas which influence the overlying high permeability material to generate magnetically active regions indicated as 134 , 135 , 136 , 137 and 138 . Region 139 is not active, and thus constitutes a magnetic zero. When read by an interrogation system such as that of FIG. 8, the output generated by tags 100 , 120 and 130 will be as shown in FIG. 9 d.
A more complex tag is shown in FIG. 9 c . Here there are a series of parallel linear arrays of magnetically active material, generating a 4×4 array of sites where the magnetically active material may be present (coding as ‘1’) or absent (coding as ‘0’).
FIG. 10 illustrates the general arrangement of three sets of coils as used in accordance with this invention for surgical applications. The three sets of coils are all mutually orthogonal and define a cavity into which the head 200 of a patient may be positioned. The first coil set consists of coils 201 a and 201 b ; the second set consists of coils 202 a and 202 b ; and the third set consists of coils 203 a and 203 b . In the drawing, two surgical probes 204 and 205 are shown schematically in position within the patient's cranium. The probes each have, at their distal ends, a magnetic tag 206 , 207 such as one of those described with reference to FIG. 9 above. Because the magnetic element of the tag is only required to provide information of its presence (rather than hold extensive data), relatively simple tags are preferred. A single magnetic element of high permeability magnetic material located at the tip of the probe is sufficient. The coils are operated in the manner described in detail hereinabove. By means of the present invention, it is possible to determine the positions of the ends of the probes with high precision—and thus to carry out delicate surgical procedures with accuracy and with minimum damage to healthy tissue. | Magnetic tags or markers are disclosed, together with a variety of techniques by means of which such tags may be interrogated. In one aspect, the magnetic marker or tag which is characterised by carrying a plurality of discrete magnetically active regions in a linear array. In another aspect, the invention provides a method of interrogating a magnetic tag or marker within a predetermined interrogation zone, the tag compromising a high permeability magnetic material, for example to read data stored magnetically in the tag or to use the response of the tag to detect its presence and/or to determine its position within the interrogation zone, characterized in that the interrogation process includes the step of subjecting the tag sequentially to: (1) a magnetic field sufficient in field strength to saturate the high permeability magnetic material, and (2) a magnetic null as herein defined. Applications of such techniques are described, inter alia, in relation to (a) identifying articled to which tags are attached; (b) accurate determination of position, as in the location of surgical probes; (c) totalisation of purchases, where each item carries a tag coded with data representing its nature and its price. | 8 |
TECHNICAL FIELD
This invention relates generally to improved microwave monolithic integrated circuits, and more specifically to heat radiating electrodes for such circuits.
BACKGROUND ART
Microwave monolithic integrated circuits (MMIC) made of gallium arsenide (GaAs) are well known in the art and typically have a configuration similar to that which is shown in FIG. 1. More specifically, a GaAs MMIC 10 generally comprises a GaAs substrate 11 having an active region 12 and first and second passive regions 13, 14. The active region 12 may, for example, comprise at least one MESFET having three electrodes: a drain 15a, a gate 15b and a source 15c. The drain 15a and the source 15c may be respectively connected to the microwave band matching circuits comprising the passive regions 13, 14 by means of metallized bridges (not shown in FIG. 1). Constituted as such, the GaAs MMIC 10 may be used as a high frequency amplifier.
In a GaAs MMIC used as a high output amplifier, the operational temperature of the active region 12 may exceed 100° C. Therefore, it is important that the MMIC be provided with means for radiating the heat, thereby enhancing its operational characteristics and reliability. In the prior art GaAs MMIC shown in FIG. 1, heat generated in the active region 12 radiates downwardly through the GaAs substrate 11. Since GaAs has a low thermal conductivity, however, the heat radiation characteristics of this prior art GaAs MMIC are inadequate.
Another prior art GaAs MMIC, in which a relatively good heat radiation effect is obtained, is shown in FIG. 2C. GaAs MMICs of such construction are disclosed in "A Packaged 20-GHz 1-W GaAs MESFET with a Novel Via-Hole Plated Heat Sink Structure" and "A K-Band GaAs FET Amplifier with 8.2-W Output Power", which appeared in IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-32, No. 3, March 1984 at pages 309-316 and 317-324, respectively.
A method of producing this type of GaAs MMIC is illustrated in FIG. 2. First, as shown in FIG. 2A, a coating of wax 16 is provided over the entire surface of the MMIC to protect the active region 12 and the passive regions 13, 14, and a glass plate 17 is provided thereon. The GaAs substrate 11 is then reduced to a thickness of approximately 50 microns by grinding, for example. Thereafter, titanium and gold are successively plated on the GaAs substrate 11, thereby producing a titanium cladding layer 18 and a gold cladding layer 19. Next, as shown in FIG. 2B, a plated heat sink (PHS) 20 having a thickness of approximately 50 microns is electrolytically plated on the gold cladding layer 19. Preferably, the plated heat sink should be comprised of a material having high thermal conductivity, such as gold. To complete the production of the GaAs MMIC, the glass plate 17 and the wax 16 are removed (see FIG. 2C).
In a GaAs MMIC having a structure such as described above and shown in FIG. 2C, heat generated in the active region 12 is more efficiently radiated through the PHS 20. However, due to the substantially decreased thickness of the GaAs substrate underlying the passive regions, the pattern sizes of the microwave transmission lines in those regions must be narrowed to achieve proper impedance matching. Consequently, the transmission losses of the lines are increased.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide an improved microwave monolithic integrated circuit which is highly efficient and reliable, having excellent heat radiation characteristics and low transmission losses in the microwave operation band.
A further object of the present invention is to provide such an improved microwave monolithic integrated circuit in which the patterning of the passive regions may be easily achieved.
Other objects and advantages of the invention will be apparent from the following detailed description.
In accordance with the present invention, there is provided a a microwave monolithic integrated circuit comprising a semiconductor or semiinsulator substrate having upper and lower opposed surfaces. At least one active region and at least one passive region are produced on the upper surface of the substrate. A heat sink is plated on the lower surface of the semiconductor substrate. Prior to applying the plated heat sink, the substrate lower surface is altered to render the substrate thickness beneath the active region smaller than the substrate thickness beneath at least one passive region, thereby disposing the heat sink near the active region to improve the heat dissipation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a prior art MMIC;
FIGS. 2A to 2C illustrate in cross section a prior art process for producing an MMIC having a heat sink plated thereon;
FIG. 3 is a perspective view of a prior art microwave transmission line of general construction;
FIG. 4 is a graph showing the relationship between the W/H quotient and the characteristic impedance Z 0 of the prior art microwave transmission line of FIG. 3;
FIGS. 5A to 5D illustrate in cross section a process for producing electrical interconnections between the passive and active regions of a MMIC;
FIGS. 6A to 6G illustrate in cross section a process for producing a MMIC according to a first embodiment of the present invention;
FIG. 7 is a cross-sectional view showing the path through which heat is radiated from the active region of a prior art MMIC; and
FIG. 8 is a cross-sectional view of a second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
While the invention will be described in connection with certain preferred embodiments, it will be understood that it is not intended to limit the invention to these particular embodiments. On the contrary, it is intended to cover all alternatives, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims.
Typically, each of the passive regions of a MMIC is associated with a microwave transmission line having a predetermined pattern size (i.e., width) and a desired characteristic impedance. As is well known in the art, there is a predetermined relationship between the pattern size of a microwave transmission line, the characteristic impedance thereof, and the thickness of the substrate beneath the transmission line. Specifically, when a microwave transmission line 21 has a predetermined width W and the substrate material 22 beneath the microwave transmission line 21 has a thickness H (see FIG. 3), the characteristic impedance Z 0 of the microwave transmission line is defined by the following formulae: ##EQU1## wherein the entire transmission line device has a dielectric constant ε rE defined by ##EQU2## in which ε r is the dielectric constant of the substrate material 22 and the function F(W/H) is defined by ##EQU3##
FIG. 4 shows the relationship between the W/H quotient and the characteristic impedance Z 0 of the microwave transmission line at different dielectric constant ε r values for the underlying substrate material. Thus, it may be seen that the characteristic impedance Z 0 decreases as the W/H quotient increases (i.e., as the width of the transmission line increases or the thickness of the underlying substrate material decreases). Accordingly, if it is desired to maintain the characteristic impedance Z 0 of a transmission line at a constant value as the thickness H of the substrate underlying the line is decreased, the width W of the line must also be decreased. In other words, in producing microwave transmission lines associated with the passive regions of a MMIC, it must be kept in mind that the thinner the substrate is beneath the passive sections, the smaller the transmission line pattern size must be to keep the characteristic impedance constant. Decreasing the pattern size makes it harder to produce and increases the transmission losses of the line at microwave frequencies, thus deteriorating the overall characteristics of the MMIC.
Referring to FIGS. 5A to 5D, there is shown a method of interconnecting the active region of a MMIC with its passive regions. A MMIC generally comprises (FIG. 5A) a semiconductor or semiinsulator substrate 23 having an active region 24 (which may include at least one MESFET) and first and second passive regions 25, 26. The active region 24 has three electrodes: a drain 27a, a gate 27b, and a source 27c. A resist 28 is selectively placed on the top surface of the MMIC (see FIG. 5B), covering all but the drain 27a, the source 27c, and portions of the two passive regions 25, 26. The entire surface of the resist 28 is then coated with a metal film 29 so that the active and passive regions of the MMIC are electrically interconnected. Another resist 30 is then selectively placed above portions of the active and passive regions of the MMIC (FIG. 5C) and, thereafter, a metallized layer 31 is electrolytically produced using the metal film 29 as the electrode. Finally, the two resists 28, 30 are removed, producing two metallized bridges 32 (each comprising portions of the metal film 29 and the electrolytic metallized layer 31) which electrically connect the drain 27a to a first passive region 25 and the source 27c to a second passive region 26, respectively. As so configured (FIG. 5D), the MMIC may be used as an amplifier, but, as discussed above, would have inadequate heat radiating characteristics.
In accordance with a first embodiment of the present invention, portions of the substrate 23 of a MMIC are selectively decreased in thickness using well-known grinding and etching techniques and a heat sink is plated on the newly-configured lower surface of the substrate. This process is described in greater detail below with reference to FIGS. 6A to 6G.
First, as shown in FIG. 6A, a coating of wax 33 is provided which completely covers the top surface of the MMIC, including the active region 24, the passive regions 25, 26 and the metallized bridges 32 therebetween. A glass plate 34 is then placed over the layer of wax 33, and together these elements serve to protect the active and passive regions, and their interconnections, while the bottom surface of the substrate 23 is being worked.
After the wax coating 33 and the glass plate 34 are in place, the bottom surface of the substrate 23 is ground away so that the entire substrate has a uniform predetermined thickness. For example, as shown in FIG. 6B, the bottom surface of the substrate 23 is ground until the thickness of the substrate is equal to a thickness T 1 which is desired under the passive region 26 for output impedance matching purposes. Thereafter, the portion of the bottom surface of the substrate 23 underlying the passive region 26 is coated with a resist mask 35, and the uncoated portion is etched using a conventional technique, such as reactive ion etching. Thus, the thickness of the substrate 23 beneath the passive region 26 is maintained at the desired dimension T 1 , while the remainder of the substrate is further decreased in thickness (FIG. 6C) until it equals a thickness T 2 which is desired beneath the other passive region 25 for input impedance matching purposes. A second resist 36 is placed on the portion of the lower surface of the substrate 23 underlying the passive region 25, and the remaining uncoated portion is further etched. Once the thickness of the substrate underlying the active region 24 is decreased to its desired dimension T 3 (FIG. 6D), the etching again ceases and a third resist 37 is placed on the portion of the lower surface of the substrate underlying the active region 24. Etching is then resumed until substantially all of the substrate 23 underlying the regions intermediate to the active region 24 and the passive regions 25, 26 is removed (FIG. 6E).
Next, the three resist masks (35, 36 and 37) are removed and a non-electrolytic metallized cladding layer 38 (having a thickness of approximately 0.5 microns and comprising nickel and gold, for example) is deposited on the entire lower surface of the etched substrate 23 (FIG. 6F). Using this cladding layer 38 as an electrode, a layer of gold (or other metallized material having a high thermal conductivity) is then electrolytically plated on the entire underside of the MMIC to form a heat sink 39. This heat sink underlies the active and passive regions of the MMIC and fills the intermediate regions so as to at least partially surround the portion of substrate beneath the active region. Finally, as shown in FIG. 6G, the bottom surface of the heat sink layer 39 is ground flat, and the glass plate 34 and the wax 33 are removed from the top surface of the MMIC.
With this configuration, the active region of a MMIC has substantially improved heat radiating characteristics. A large part of the heat generated by the active region is irradiated downwardly by diffusion through the underlying substrate. This characteristic is shown in FIG. 7 for a prior art MMIC, wherein approximately eighty percent of the generated heat is diffused through a conical section A of the substrate 11 underlying the active region 12. It is therefore understandable that such prior art MMICs have poor heat radiating characteristics, since the thick substrate has a low thermal conductivity (e.g., GaAs has a thermal conductivity of 0.8 W/cm·deg) and, thus, prevents efficient heat radiation.
In contrast, a MMIC configured in accordance with the above-described embodiment of the present invention (FIG. 6G) has only a relatively thin substrate of semiconductor or semiinsulator material underlying the active region 24, and has a heat sink 39 having a relatively high thermal conductivity (e.g., the thermal conductivity of gold is approximately 3.1 W/cm·deg) provided to surround that portion of the substrate. Heat generated in the active region 12 quickly escapes through both the bottom and side surfaces of the underlying thin substrate into the highly conductive heat sink 39, thereby transversely expanding the heat radiation zone of the MMIC substantially beyond the conical section A shown in FIG. 7 for the prior art configuration. Accordingly, heat is diffused more rapidly, suppressing the operating temperature of the MMIC and enhancing its reliability.
It should be noted that in practicing this invention it is possible to reduce the substrate underlying the active region to a thickness T 3 as small as 0.5 microns. However, in order to maximize the performance characteristics of the active region (which may comprise at least one MESFET), it is best that the substrate beneath that region have a thickness T 3 in the range of 30-100 microns, with 30, 50 and 100 microns being preferred values in that range. With regard to the substrate portions intermediate to the active and passive regions, it is preferable to reduce those portions to a thickness of approximately 0.5 microns in order to maximize the transverse diffusion of heat.
As discussed above, a further benefit of this invention is that it provides for relatively simple establishment of desired characteristic impedances (Z 0 ) for the respective microwave transmission lines associated with the passive regions. Thus, in accordance with the previously discussed formulae relating to Z 0 , it is possible to set the characteristic impedance of a microwave transmission line having a preset width W to a desired value by decreasing the thickness (T 1 , T 2 ) of the semiconductor substrate underlying the respective passive region. Typically, the substrates underlying the passive regions of the MMIC should have thicknesses in the range of 100-200 microns, with 100, 150 and 200 micron thicknesses being preferred to establish typical input and output impedances for transmission lines having standard pattern sizes (i.e., widths).
It will be noted, therefore, that the present invention provides improved heat radiating characteristics for the active region of the MMIC, while, at the same time, providing for impedance matching without adjusting the pattern sizes of the respective transmission lines associated with the passive regions. Thus, large standard pattern sizes may be used, making production of the MMIC easy and reducing transmission losses in the microwave operating band.
A second embodiment of a MMIC according to the present invention is shown in FIG. 8. This embodiment is substantially the same as the embodiment of FIG. 6G, except that the portions of the substrate 23 beneath the two passive regions 25, 26 have equal respective thicknesses T 1 , T 2 and have no underlying plated heat sink. This is accomplished by applying a resist mask (such as mask 35 in FIG. 6B) which covers both portions of the bottom surface of the substrate underlying the two passive regions and, thereafter, etching the substrate beneath only the active and intermediate regions. Accordingly, a heat sink 39 is provided only under the active and intermediate regions so as to at least partially surround the substrate portion beneath the active region. Nevertheless, due to the decreased thickness T 3 of the substrate 23 beneath the active region and the close proximity of the heat sink 39 to the active region, this embodiment of the present invention also exhibits excellent heat radiating characteristics.
As can be seen from the foregoing detailed description, this invention provides an improved microwave monolithic integrated circuit which has excellent heat radiating characteristics and low microwave operation transmission losses and is, therefore, highly efficient and reliable. Moreover, this invention provides for impedance matching of the input and output of the MMIC while utilizing standard, easily-produced, pattern sizes for the transmission lines associated with the passive regions. | A microwave monolithic integrated circuit comprising a GaAs substrate having upper and lower opposed surfaces, an active region and at least one passive region produced on the upper surface of the substrate, and a heat sink produced on the lower surface of the substrate, wherein the substrate thickness beneath the active region is smaller than the substrate thickness beneath at least one passive region, thereby disposing the heat sink near the active region to improve heat dissipation therefrom. The active region and the passive regions are separated by intermediate areas and the substrate thickness beneath the intermediate areas is smaller than the substrate thickness beneath the active region such that the heat sink at least partially surrounds the substrate beneath the active region. Each passive region is associated with a respective microwave transmission line having a predetermined width and a desired characteristic impedance and the thickness of the substrate beneath each of the passive regions is established individually based on the width and the desired characteristic impedance of each respective microwave transmission line. | 8 |
[0001] This application is a continuation-in-part of application Ser. No. 10/803,009, filed on Mar. 17, 2004, now pending.
FIELD OF THE DISCLOSURE
[0002] The disclosure relates to micro-fluid ejection devices. More particularly, the disclosure relates an improved method for making micro-fluid ejection devices in order to increase the yield of usable product.
BACKGROUND
[0003] Micro-fluid ejection head such as used in ink jet printers are a key component of ink jet printer devices. The processes used to construct such micro-fluid ejection heads require precise and accurate techniques and measurements on a minute scale. Some steps in the ejection head construction process are necessary but can be damaging to the ejection head. Such damage to the ejection head affects the quality of fluid output, and, therefore, has an affect on the value of the ejection device containing the ejection head.
[0004] One example of a technique that can result in such damage to an ejection head is the removal of an etch mask layer from photoresist planarization and protection layer on a semiconductor chip in a given ejection head. Ejection heads include a silicon substrate and a plurality of layers including passivation layers, conductive metal layers, resistive layers, insulative layers, and protective layers on the substrate. Fluid feed holes or fluid supply slots are formed in the substrate and various layers in order for fluid to be transferred through the holes or slots to ejection devices on a substrate surface. Such holes of slots are often formed through the semiconductor chip using deep reactive ion etching (DRIE) or mechanical techniques such as grit blasting. A planarization and protection layer is preferably used to smooth the surface of the semiconductor chip so that a nozzle plate may be attached to the substrate more readily. The planarization layer also functions to protect the components between the planarization layer and the surface of the substrate from corrosion.
[0005] Before holes or slots are formed in the semiconductor chip containing a planarization layer, the planarization layer is desirably masked by an etch mask layer. Like the planarization layer, the etch mask layer is typically a photoresist material. In order to complete the hole formation process, the etch mask layer must be removed. However, techniques sufficient to remove the etch mask layer may also strip away portions of the planarization layer that are needed for protection of underlying layers. This undesirable effect results in less protection for the semiconductor chip. If, on the other hand, less aggressive stripping of the etch mask layer is conducted, portions of the semiconductor chip are left with an insoluble residue from the etch mask layer which makes the chips unsuitable for use. There is, therefore, a continuing need for a process that will remove substantially all of the etch mask layer without damaging the underlying planarization and protection layer.
SUMMARY
[0006] With regard to the above and other objects the disclosure describes a method of etching a semiconductor substrate. The method includes the steps of applying a photoresist etch mask layer to a device surface of the substrate. A select first area of the photoresist etch mask is masked, imaged and developed. A select second area of the photoresist etch mask layer is irradiated to assist in post etch stripping of the etch mask layer from the select second area. The substrate is etched to form fluid supply slots through a thickness of the substrate. At least the select second area of the etch mask layer is removed from the substrate, whereby mask layer residue formed from the select second area of the etch mask layer is significantly reduced.
[0007] In another embodiment there is provided a process of forming one or more fluid feed slots in a semiconductor substrate chip for use in a micro-fluid ejection head. The process includes applying a photoresist planarization layer to a first surface of the chip. The planarization layer has a thickness ranging from about 1 to about 10 microns. The photoresist planarization layer is patterned and developed to define at least one ink feed via location therein and to define contact pad areas for electrical connection to a control device. A photoresist etch mask layer is applied to the photoresist planarization layer on the chip. The photoresist etch mask layer has a thickness ranging from about 10 to about 100 microns. The photoresist etch mask layer patterned and developed with a first photomask to define the at least one fluid supply slot location in the photoresist etch mask layer. Deprotection of the photoresist etch mask layer in a select second area of etch mask layer is induced by exposing the select second area to radiation through a second photomask. The exposure through the second photomask is sufficient to deprotect the photoresist etch mask layer in the select second area so that the photoresist etch mask layer in the select second area can be substantially removed with a solvent without substantially affecting the photoresist planarization layer. The chip is dry etched to form at least one fluid supply slot in the defined at least one fluid supply slot location. Subsequently, the photoresist etch mask layer is removed from the planarization layer.
[0008] An advantage of certain embodiments described herein may be that select areas of the photoresist etch mask may be essentially completely removed from the substrate with less aggressive techniques. Also, the planarization layer is left relatively smooth and substantially unaltered after the dry etching process and removal of the photoresist etch mask layer. Unlike conventional techniques used to remove etch mask layers, the exemplary embodiments described herein provide removal of substantially all of the photoresist etch mask layer, leaving essentially no residue on critical components such as electrical bond pads thereby improving product yield.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Further features and advantages of the embodiments described herein will become apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale, wherein like reference numbers indicate like elements through the several views, and wherein:
[0010] FIG. 1 is a cross-sectional view, not to scale, of a micro-fluid ejection head;
[0011] FIGS. 2-8 illustrate steps in a process for forming a micro-fluid ejection head according to one embodiment of the invention;
[0012] FIG. 9A is a cross-sectional view, not to scale, of an imaging process for activating select areas of a photoresist etch mask layer using radiation according to an embodiment of the disclosure;
[0013] FIG. 9B is a plan view, not to scale, of an etch mask for imaging a photoresist etch mask layer according to the disclosure;
[0014] FIG. 10 is a photomicrograph of a contact pad of a substrate containing residue from removal of a photoresist etch mask layer by a prior art method;
[0015] FIG. 11 is a photomicrograph of a contact pad of a substrate after removal of a photoresist etch mask layer treated with radiation according to the disclosure;
[0016] FIG. 12 is a plan view, not to scale, of a etch mask for imaging a photoresist etch mask layer according to another embodiment of the disclosure;
[0017] FIG. 13 is a cross-sectional view, not to scale, of a reactive ion etch process according to the disclosure; and
[0018] FIG. 14 is a cross-sectional view, not to scale, of a substrate according to the disclosure after removal of an etch mask layer.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0019] In one embodiment, there are provided methods for substantially removing an etch mask layer from a surface of a silicon substrate during a manufacturing process for making a semiconductor silicon chip used in micro-fluid ejection devices, such as ink jet printers. With reference to FIG. 1 , a micro-fluid ejection head 10 for a micro-fluid ejection device such as an ink jet printer includes a semiconductor substrate 12 , preferably made of silicon, having a thickness T. The substrate includes a plurality of fluid ejection devices such as heater resistors 14 on a device surface 16 thereof. The device surface 16 of the substrate 12 also includes various conductive, insulative and protective layers for electrically connecting the heater resistors 14 to a control device for ejecting fluid from the ejection head 10 and for protecting the resistors 14 from corrosion by contact with the fluid.
[0020] In order to provide a relatively planar surface for attaching a nozzle plate 18 to the substrate 12 , a planarization layer 20 may be applied to the device surface 16 of the substrate 12 . An exemplary planarization layer 20 is provided by a radiation curable resin composition that may be spin-coated onto the surface 16 of the substrate 12 . A particularly advantageous radiation curable resin composition includes a difunctional epoxy component, a multifunctional epoxy component, a photoinitiator, a silane coupling agent, and a nonphotoreactive solvent, generally as described in U.S. Publication No. 2003/0207209 to Patil et al., the disclosure of which is incorporated by references as if fully set forth herein.
[0021] The nozzle plate 18 includes nozzle holes 22 and may include fluid chambers 24 laser ablated therein. In the alternative a thick film layer may be attached directly to the planarization layer 20 and a nozzle plate attached to the thick film layer. In the case of a separate thick film layer, the ink chambers are typically formed in the thick film layer and the nozzle holes are formed in the nozzle plate.
[0022] A fluid supply slot 26 is formed through the thickness T of the semiconductor substrate 12 to provide a fluid supply path for flow of fluid to the fluid chambers 24 and heater resistors 14 . The fluid supply slot 26 may be provided by an elongate slot or individual holes through the thickness T of the substrate 12 . Methods for making fluid supply slots 26 are known and include mechanical abrasion, chemical etching, and dry etching techniques. A particularly advantageous method for forming a fluid supply slot 26 is a deep reactive ion etching (DRIE) process, generally as described in U.S. Pat. No. 6,402,301 to Powers et al., the disclosure of which is incorporated by reference as if fully set forth herein. While the fluid supply slot 26 is shown as having substantially vertical walls, the walls of the fluid supply slot 26 are typically slightly tapered so that the fluid supply slot 26 is wider on one end than on the other end.
[0023] With reference to FIGS. 2-11 , an exemplary method for making micro-fluid ejection devices according to one embodiment of the disclosure is illustrated. The method includes providing a substrate 12 having a thickness ranging from about 200 to about 800 microns or more. A plurality of layers including insulative, conductive, and resistive materials are deposited on the device surface 16 of the substrate to provide a plurality of heater resistors 14 thereon and electrical tracing to the heater resistors 14 . The substrate 12 may also include driver transistors and control logic for the resistors 14 and contact pads 27 for connecting the heater resistors 14 to a control device as by use of a tape automated bonding (TAB) circuit or flexible circuit connected to the contact pads 27 .
[0024] In the next step of the process, shown in FIG. 3 , a planarization layer 20 , as described above, is applied to the surface 16 of the substrate. The planarization layer may have a thickness ranging from about 1 to about 10 microns or more. Since the planarization layer 20 may be spin-coated onto the substrate surface 16 , the layer 20 may be made to completely cover the exposed surface 16 of the substrate 12 including the heater resistors 14 and contact pads 27 as shown. The result after the deposition of the planarization layer 20 is a planarized surface 28 .
[0025] Next, with reference to FIG. 4 , the planarization layer 20 is photoimaged to cure selected portions of the layer 20 . The selected portions of the planarization layer 20 may be cured using a radiation source 30 such as ultraviolet (UV) radiation. A mask 32 having radiation blocking areas 31 and 33 is used to shield one or more portions and of the planarization layer 20 from the radiation 30 as illustrated so that the shielded portions of the planarization layer 20 remain uncured. The uncured portions are located in areas that are to be developed and removed from the device surface 16 of the substrate 12 . Accordingly, the planarization layer 20 atop the resistors 14 and contact pads 27 is removed and the device surface 16 of the substrate is exposed in location 34 for the fluid supply slot 26 . The fully cured and developed planarization layer 20 is illustrated in FIG. 5 .
[0026] With reference to FIG. 6 , an etch mask layer 36 is then applied to the planarization layer 20 , the exposed location 34 of the substrate 12 and the exposed contact pads 27 . The layer 36 acts as an etch mask layer for a DRIE process for forming one or more fluid supply slots 26 or holes through the thickness T of the substrate 12 . The etch mask layer 36 desirably has a thickness ranging from about 10 to about 100 microns, and more particularly, from about 30 to about 70 microns. The thickness of the etch mask layer 36 is not critical provided the thickness is sufficient to protect the planarization layer 20 , heater resistors 14 , and contact pads 27 during the etching process and not so thick that it inhibits a photoimaging process.
[0027] The etch mask layer 36 may be provided by a photoresist material comprised of a polymer containing acid labile protecting groups thereon. An exemplary polymer for use as the etch mask layer 36 includes a protected polyhydroxystyrene material available from Shin-Etsu MicroSi, Inc. of Phoenix, Ariz. under the trade name SIPR 7121M-16, and generally described in U.S. Pat. No. 6,635,400 to Kato et al., the disclosure of which is incorporated herein by reference thereto.
[0028] A second irradiation process as illustrated in FIG. 7 is used to provide a select first area 37 in the etch mask layer 36 for forming one or more fluid supply slots 26 through the thickness T of the substrate 12 . A second mask 38 is used to photoimage the etch mask layer 36 using a radiation source 40 such as UV radiation. Unlike the process described with respect to FIG. 4 , portions of the etch mask layer 36 in the first area 37 subject to radiation are transformed into materials that are readily removed with a suitable solvent rather than cured to prevent removal with a solvent. In the case of use of the photoresist etch mask layer 36 having acid labile protecting groups thereon, irradiation of the etch mask layer 36 causes deprotection of the acid labile protecting groups. Conventional developing solutions may then be used to remove portions of the etch mask layer 36 in area 37 wherein the substrate surface 16 is exposed as shown in FIG. 8 .
[0029] Prior to etching the substrate 12 , a third radiation process is used in conjunction with an etch mask 42 ( FIGS. 9A and 9B ) to irradiate select second areas 44 of the etch mask layer 36 for subsequent removal after the dry etch process is complete. Accordingly, the etch mask 42 contains substantially transparent areas 46 ( FIG. 9B ) corresponding to select second areas 44 on the substrate. The mask 42 is configured to expose the select second areas 44 which correspond to the contact pads on the substrate to enable easy removal of the photoresist etch mask layer 36 from the contact pads 27 .
[0030] Without desiring to be bound by theory, it is well known that exposure of a positive photoresist to UV radiation causes the photoresist to react in such away that solubility of the photoresist is increased in alkaline solvents as well as organic solvents such as acetone. The same is true for both chemically amplified positive photoresist materials as well as standard positive photoresist materials. However, in the embodiments described herein, a chemically amplified positive tone photoresist as described above is used as the etch mask layer 36 . Chemically amplified resists (CAR's) contain a phototacid generator (PAG) which upon exposure to the appropriate UV wavelengths will generate an acid and deprotect the photoresist thereby altering the solubility of the photoresist material. In the case of the use of a polyhydroxystyrene material as described above as the etch mask layer 36 , exposure to UV radiation induces deprotection of the acid labile groups in the mask layer 36 so that the layer 36 can then be cleanly removed with a solvent in which the mask layer 36 is substantially soluble while the cured planarization layer 20 remains substantially unaffected by the solvent. Suitable solvents include, but are not limited to, compounds in which polyhydroxystyrene is substantially soluble. Examples of such solvents include propyleneglycol monomethyletheracetate (PGMEA), cyclopentanone, N-methylpyrrolidone, aqueous tetramethyl ammonium hydroxide, acetone, isopropyl alcohol, and butyl cellosolve acetate. Aqueous tetramethyl ammonium hydroxide is particularly suitable for removing a chemically amplified resist.
[0031] It will be appreciated that during a DRIE process, the substrate 12 and the photoresist etch mask layer 36 are exposed to a variety of environmental conditions including UV radiation and heat. The extent of the exposure of the etch mask layer 36 to these conditions affects the stripability of the photoresist etch mask layer 36 upon completion of the etch process. Heat and UV radiation cause the photoresist etch mask layer 36 to interact with contact pads 27 , particularly contact pads 27 made of aluminum-copper. A photomicrograph of a contact pad 27 A using a prior art etch process having a residue 48 thereon after photoresist stripping is illustrated in FIG. 10 . In the prior art process, the step illustrated and described with respect to FIG. 9A is omitted.
[0032] It has been observed that if the substrate 12 has the residue 48 on the contact pads 27 , electrical leads connected to the contact pads 27 will not adequately bond to the pads 27 causing the ejection head to be discarded. However, if the photoresist etch mask layer 36 is deprotected in select areas 44 by exposing the select areas 44 to UV radiation prior to the DRIE step used to form the fluid supply slots 26 , then stripping of the etch mask layer 36 from the substrate 12 and planarization layer 20 is substantially improved as illustrated by the photomicrograph of a contact pad 27 B illustrated in FIG. 11 .
[0033] Exposure of select areas 44 of the photoresist etch mask layer 36 to UV radiation is conducted at an unconventional time. The exposure step, illustrated in FIG. 9A is conducted after the initial imaging and photoresist development steps illustrated in FIGS. 7 and 8 and before a DRIE step illustrated in FIG. 14 . Accordingly, the exposed areas 44 of the photoresist etch mask layer 36 are not washed away during the initial development cycle illustrated in FIG. 8 .
[0034] Blanket exposure of the photoresist etch mask layer 36 without the use of etch mask 42 to provide selective exposure is detrimental to the DRIE etch process as lateral etching of walls for the fluid supply slot 26 in the first area 37 may occur. Accordingly, the etch mask 42 is beneficial in selectively exposing areas of the photoresist etch mask layer 36 prior to DRIE etching.
[0035] In the case of chemically amplified resists, there is a short delay time between exposure of the select areas 44 of the photoresist etch mask layer 36 and the DRIE etching step. The delay time should be sufficient to enable the etch mask layer 36 in the select areas 44 to react to the exposure before the DRIE etch process is conducted. Typically, at least a five minute delay time may be required for reaction, depending on the thickness of the etch mask layer 36 .
[0036] In another embodiment, a mask 50 as illustrated in FIG. 12 may be used to expose the select second areas 44 to UV radiation through transparent areas 52 . Rounding the corners of the transparent areas 52 as shown may reduce internal stresses in the photoresist etch mask layer that may cause photoresist cracking.
[0037] In yet another embodiment, all areas of the photoresist etch mask layer 36 are exposed to UV radiation, except areas immediately adjacent the select first area 37 for etching the fluid supply slots 26 . Accordingly, exposure of the photoresist etch mask layer 36 may include all areas greater than about 0 to about 30 microns from the first area 37 . Such an overall exposure has the advantage of increasing etch mask layer 36 stripability over the largest substrate area without substantially contributing to lateral etching of the fluid supply slots 26 .
[0038] The UV radiation dose and spectrum for exposing the select second areas 44 are chosen such that the UV radiation induces a chemical transformation of the photo active compound in the photoresist etch mask layer 36 (.i.e., deprotection and or rearrangement) thereby reducing interaction between the etch mask layer 36 and the Al—Cu surface of the contact pads 27 . Further, since this exposure is done selectively, the lateral etch problem associated with etching the fluid supply slots 26 may be avoided.
[0039] After exposing the photoresist etch mask 36 to UV radiation as set forth above, formation of the ink vias 26 is provided by DRIE 54 as described above. FIG. 13 illustrates an exemplary dry etching process used for forming the one or more fluid supply slots 26 through the thickness T of the substrate 12 . Once the fluid supply slot 26 is formed through the thickness of the substrate 12 , the etch mask layer 36 may be removed as shown in FIG. 14 . Finally, with reference to FIG. 1 , the nozzle plate 18 is then attached to the planarization layer 20 to provide the micro-fluid ejection head 10 described above.
[0040] Having described various aspects and exemplary embodiments of the disclosure and several advantages thereof, it will be recognized by those of ordinary skills that the disclosed embodiments are susceptible to various modifications, substitutions and revisions within the spirit and scope of the appended claims. | A method of etching a semiconductor substrate. The method includes the steps of applying a photoresist etch mask layer to a device surface of the substrate. A select first area of the photoresist etch mask is masked, imaged and developed. A select second area of the photoresist etch mask layer is irradiated to assist in post etch stripping of the etch mask layer from the select second area. The substrate is etched to form fluid supply slots through a thickness of the substrate. At least the select second area of the etch mask layer is removed from the substrate, whereby mask layer residue formed from the select second area of the etch mask layer is significantly reduced. | 1 |
This application is a continuation of U.S. application Ser. No. 376,857 filed May 10, 1982 by the same inventors, which is now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the art of polymerization, and more particularly to the art of making polymer compositions which release from surfaces contacted during processing.
2. Discussion of the Technology
Release of polymer materials from molds or other processing surfaces is generally accomplished by applying a release agent at the interface of the polymer and the processing surface.
For example, U.S. Pat. No. 3,808,077 to Rieser et al discloses fabricating bilayer safety glass by assembling a preformed plastic sheet between a glass sheet and a mold coated with a release agent such as polyvinylidene fluoride, polyethylene glycol terepthalate, organopolysiloxanes, and high silica content glass resins.
U.S. Pat. No. 4,278,299 to Cherenko et al discloses a mold release composition comprising a phenyl methyl polysiloxane resin and a phenyl methyl siloxane fluid useful in laminating polyurethane to glass.
U.S. Pat. No. 3,900,686 to Ammons et al discloses that a combination of an organic phosphorus acid such as stearyl acid phosphate and an organic silane provides controlled adhesion between polyurethane and glass layers in a laminate.
Inert materials which affect the adhesion of a polymeric material to a contacting surface may be considered nonreactive internal release agents. However, these may be incompatible with the polymer composition at levels high enough to effect release. For example, the release agent may form a haze in an otherwise transparent polymer.
SUMMARY OF THE INVENTION
The present invention provides a polymer reaction mixture with a reactive internal release agent. Polyurethane compositions of the present invention achieve improved release from a casting cell or mold by means of a low adhesion surface provided by long chain hydrocarbon or fluorocarbon radicals pendent from the polymer backbone. Compounds useful in accordance with the present invention contain at least one functional group capable of reacting with the isocyanate or polyol urethane reactants. Since these compounds are reactive internal release agents, incompatibility with the reaction mixture is not a problem.
Release properties are provided by a straight or branched chain hydrocarbon or fluorocarbon compound, preferably having at least 6 carbon atoms beyond the reactive functional group, which carbon chain is pendent from the polymer backbone. Long chain hydrocarbons and fluorocarbons, typically containing at least about 8 carbon atoms and containing hydroxyl or amine groups capable of reacting with isocyanate groups, are suitable reactive internal release agents for polyurethane reaction mixtures. Alternatively, long chain hydrocarbon or fluorocarbon compounds containing isocyanate groups capable of reacting with hydroxyl groups in the polyol component of the urethane reaction mixture may be used. Long chain acids or anhydrides may be used as reactive internal release agents in polyester reaction mixtures, while long chain aldehydes may be used in polyacetal reaction mixtures. Long chain epoxy compounds may be used as reactive internal release agents in polyether reaction mixtures. Preferably, the reactive internal release agent has more than one functional group, provided a sufficiently long chain remains beyond the additional functional group.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Polyurethane compositions in accordance with the present invention may be broadly defined as consisting essentially of an organic polyisocyanate and an organic compound having at least two hydrogens capable of reacting with the isocyanate to form polyurethane linkages. Preferably, the composition further comprises a crosslinking agent, typically an organic compound having at least three hydrogens capable of reacting with the isocyanate. The reactive internal release agent is a long chain hydrocarbon or fluorocarbon having at least one reactive hydrogen.
The organic polyisocyanate component should preferably be an organic diisocyanate. Cyclic aliphatic diisocyanates are preferred since they are not adversely affected by ultraviolet light and have high impact energy absorption levels. In addition, polyurethanes prepared with cyclic aliphatic diisocyanates are not adversely affected by conventional processing temperatures. A preferred cyclic aliphatic diisocyanate is 4,4'-methylene-bis(cyclohexyl isocyanate). Other dinuclear cyclic aliphatic diisocyanates which are preferred are those formed through an alkylene group of from 1 to 3 carbon atoms and which can be substituted with nitro, chloro, alkyl, alkoxy and other groups which are not reactive with hydroxyl groups, provided the substituents are not positioned so as to render the isocyanate group unreactive. Another preferred dinuclear cycloaliphatic diisocyanate is 4,4'-isopropylidene-bis-(cyclohexyl isocyanate). An example of a preferred mononuclear cyclic aliphatic diisocyanate is 1,4-cyclohexyl diisocyanate. Hydrogenated aromatic diisocyanates such as hydrogenated toluene diisocyanate, as well as dinuclear diisocyanates in which one of the rings is saturated and the other unsaturated, can also be employed. Mixtures of cyclic aliphatic diisocyanates with straight chain aliphatic diisocyanates and/or aromatic diisocyanates can also be employed. Thioisocyanates corresponding to the above diisocyanates can be employed, as well as mixed compounds containing both an isocyanate and a thioisocyanate group.
Straight chain aliphatic diisocyanates such as 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,10-decamethylene diisocyanate, and hexamethylene adipamide diisocyanate can also be employed. Suitable aromatic diisocyanates, although not preferred, can be employed in some instances, and include mononuclear types such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, metaphenylene diisocyanate; dinuclear aromatic diisocyanates such as 4,4'-diphenylene diisocyananate and 1,5-naphthalene diisocyanate; halogenated substituted aromatic diisocyanates such as 4-chloro-1-3-phenylene diisocyanate; alkyl substituted diisocyanates such as 3,3'-dimethyl 4,4'-diphenylene diisocyanate; xylene diisocyanates including 1,3-xylene diisocyanate and 1,4-xylene diisocyanate; durene isocyanates such as 2,3,5,6-tetramethyl-1,4-diisocyanate; aromatic-cycloaliphatic diisocyanates such as 1,5-tetrahydronaphthalene diisocyanate; polynuclear aromatic diisocyanates bridging through aliphatic groups such as diphenyl methane diisocyanate and diphenyl isopropylidene diisocyanate; alkoxy substituted aromatic diisocyanates such as dianisidine diisocyanates; mononuclear aralkyl diisocyanates such as xylene diisocyanates; aliphatic branched chain diisocyanates such as 2,2,4-trimethylhexamethylene diisocyanate; and ester-containing aliphatic diisocyanates such as 2,6-diisocyanato methyl caproate (Lysine diisocyanate). In addition, sterically hindered compounds wherein the isocyanate groups differ in reactivity such as 2,4-diethylmethylene-bis-(4-phenylene isocyanate); 3-isocyanato methyl-3,5,5'-trimethylcyclohexyl diisocyanate and 2,6-diethyl-1,4-phenylene diisocyanate may also be employed. In addition, diisocyanates bonded from sulfonyl groups such as 1,3-phenylene disulfonyl diisocyanate and 1,4-xylene disulfonyl diisocyanate may be used.
The polyisocyanate component as described above is reacted with at least one compound containing at least two groups which are reactive with the isocyanate group. The preferred compounds are those which have at least two, preferably only two, active hydrogens per molecule, such as polyols and polyamines, preferably diols. Preferred compounds include polyester diols, polycarbonate diols and polyether diols, as well as chain extenders such as monomeric aliphatic diols, e.g. 1,4-butanediol and cyclohexanedimethanol. The polyisocyanate component also reacts with the reactive internal release agent which is defined as a compound comprising at least one hydrogen capable of reacting with the isocyanate and further comprising long chain hydrocarbon or fluorocarbon segments to provide release characteristics. Preferred internal release agents include C 12 and C 18 alcohols, preferably diols having only one terminal hydroxyl group. Most preferred are 1,2-dodecanediol and 1-octadecanol, especially in combination.
Preferred polyester diols can be prepared by the polyesterification reaction of an aliphatic dibasic acid or an anhydride thereof with a diol, preferably an aliphatic diol. Suitable aliphatic dicarboxylic acids can be represented by the formula HOOC--R--COOH wherein R is an alkylene radical containing from 2 to 12, and preferably from 4 to 8, carbon atoms, examples of which are adipic, succinic, glutaric, palmitic, suberic, azelaic and sebacic radicals. Suitable aliphatic diols contain from 2 to 15 carbon atoms, examples of which are ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and cyclohexanedimethanol. The number average molecular weight of the polyester diol prepared from aliphatic diols and carboxylic acids is preferably between about 500 and about 5000, preferably about 500 to 2000.
Polyester diols can also be made from the polymerization of lactone monomers. Polyester polyols from caprolactone can be prepared by subjecting a lactone represented by the formula: ##STR1## wherein R 1 and R 2 are each hydrogen or an alkyl of 1 to 10 carbon atoms, and n is an integer from 1 to 3, to polymerization in the presence of water or minor amounts of a low molecular weight glycol such as ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, propylene glycol, 1,6-hexanediol, glycerine, etc. The ring opening in polymerization is generally effected at a temperature between about 50° C. and 300° C., and preferably in the presence of a catalyst. Preparation of polycaprolactones is well known in the polyester art. Suitable caprolactones include epsilon-caprolactones; monoalkyl, for example, methyl and ethylepsilon-caprolactones, dialkyl, for example dimethyl and diethylepsilon-caprolactones, cyclohexylepsilon-caprolactones, etc. The preferred lactone is epsilon-caprolactone. The number average molecular weight of polyesters prepared from polycaprolactone diols should be between about 300 to 5000, preferably about 300 to 2000.
The above described polyesters can be represented by the following formulae: ##STR2## wherein R is the alkylene portion of the glycol used to prepare the polyester, R' is the alkylene portion of the dicarboxylic acid, and m is a number that ranges to about 15 or more; and ##STR3## which represents polycaprolactones, wherein n is preferably 4, R 1 and R 2 are each hydrogen or C 1 to C 10 alkyl, preferably C 1 -C 4 alkyl, R is the alkylene portion of the glycol used to ring open the lactone and x plus y is a number that ranges up to 30 or more, but x and y are not simultaneously 0.
Besides polyether and polyester diols, poly(alkylenecarbonate) diols such as poly(1,6-hexylenecarbonate) diol can be used. The preparation of the poly(alkylenecarbonate) diols can be carried out by reacting an aliphatic diol with phosgene; with a chloroformic acid ester; with a diaryl carbonate such as diphenyl carbonate, ditolyl carbonate, or dinaphthyl carbonate; or with a di-lower alkyl carbonate such as dimethyl, diethyl, or di-n-butyl carbonate, either by heating the reactants alone or with the use of an ester interchange catalyst depending on the identity of the reactants. Polycarbonates of different higher molecular weights are obtained depending on the proportions of reactants used. When carbonate ester reagents are used, a calculated quantity of the by-product monohydroxy compound is removed by distillation. Suitable alkylene diols include linear aliphatic diols having from about 4 to 10 carbon atoms such as 1,4-butanediol, 1,6-hexanediol and 1,10-decanediol, with 1,6-hexanediol being preferred. Poly(alkylenecarbonate) diols having number average molecular weights from 300 to 5000 are suitable, with a 300 to 2000 molecular weight range being preferred.
In synthesizing the polyurethanes, chain extension can be accomplished with a compound having two active hydrogens per molecule. The resulting polyurethanes have thermoplastic properties. Preferred chain extenders are aliphatic diols having a molecular weight below 250, and from 2 to 15 carbon atoms, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol and cyclohexanedimethanol.
The polyurethane can be cured with a compound having more than two active hydrogens per molecule. The resulting polyurethanes have thermosetting properties. Representative curing agents are polyols having at least three hydroxyl group, such as trimethylolpropane, trimethylolheptane, pentaerythritol and castor oil. Also suitable are mixed curing agents such as polyols having three hydroxyl groups in conjunction with a low molecular weight diol such as ethylene glycol or 1,4-butanediol. The polyols can also be mixed with polyamines having 2 or more reactive amine groups. Suitable polyamines are aromatic amines such as 4,4'-methylene-bis(2-chloroaniline) and diamino diphenyl sulfone.
For optimum results, the water content of the hydroxyl-terminated reactants should be as low as possible, and the isocyanate reaction should generally be conducted under anhydrous conditions with dry reactants, such as in a nitrogen atmosphere at atmospheric pressure. The reaction is conducted until there are essentially no free isocyanate or hydroxyl groups, (i.e. less than about 0.6 percent and preferably less than 0.3 percent by weight NCO). The ratio of reactants may vary depending upon the materials employed and the intended use of the urethane, but preferably the total number of active hydrogen atoms is approximately equivalent to the number of isocyanate groups. The NCO to active hydrogen ratio is generally from between about 0.9 to about 1.1, preferably between about 0.97 and about 1.03.
Preferably, the polurethane reaction is carried out in the presence of a catalyst. Catalysts have been found to give shorter cure times at lower temperatures and to insure complete reaction resulting in a cured polymer being essentially free of unreacted NCO groups. Suitable urethane-forming catalysts are those that are specific for the formation of the urethane structure by the reaction of the NCO group of the diisocyanate with the active hydrogen-containing compound and which have little tendency to induce side reactions. For these reasons, catalysts such as stannous salts of organic acids and organotin compounds are preferred. Preferred catalysts include stannous octoate, stannous oleate, dibutyltin diacetate, butyl stannoic acid and dibutyltin dilaurate. The amount of catalyst used in any particular reaction mixture may be determined empirically and will be determined by the desired curing time and temperature. In general, amounts of from about 5 to 1000 parts per weight of catalyst per million parts of polyurethane-forming ingredients are useful. The polyurethane compositions of the present invention may be formulated by a prepolymer method or by mixing all components simultaneously in a so-called "one-step" or bulk polymerization process.
Casting may be accomplished by merely pouring the resin into a cell, but preferably casting is accomplished by pumping a metered quantity of liquid resin into an interlayer space. After the resinous interlayer has been cast, the cell is sealed and the resin is permitted to cure in place. The time and temperature of cure will be from about 230° to 290° F. for a time up to about 24 hours. If a catalyst is present in the polyurethane the cure time can be significantly reduced from 24 to less than about 6 to 8 hours. The cured polyurethane comprising a reactive internal release agent is released from the casting cell more easily than a polyurethane composition without an internal release agent.
The present invention will be further understood from the descriptions of specific examples which follow.
EXAMPLE I
Cyclohexanedimethanol, trimethylolpropane and a polycaprolactone diol having a molecular weight of approximately 1000 are melted and mixed together under vacuum. The polycaprolactone diol component contains a UV stabilizer and an antioxidant as well as butyl stannoic acid catalyst. The equivalent weights, equivalent proportions and actual weights of the components are shown in the table below. When the temperature of the polyol mixture has dropped to about 60° C., the isocyanate component, which is at room temperature, is added. The temperature of the reaction mixture is then about 45° C. The equivalent and weight properties of the components of the reaction mixture are given below.
______________________________________Component Equivalents Weights______________________________________Trimethylolpropane 0.23 10.8Polycaprolactone diol 0.37 190.6Cyclohexanedimethanol 0.40 30.84,4'-methylene-bis-(cyclohexyl isocyanate) 1.00 131.0______________________________________
The reaction mixture is cast into a cell which comprises two 12 by 12 inch (about 30 by 30 centimeter) glass plates which define a 30 mil (0.8 millimeter) space. One of the glass sheets is coated with a siloxane release coating. The filled cell is then placed in a 300° F. oven to cure the polyurethane. When the cell is removed from the oven, and an attempt is made to remove the release plate while the cell is still hot, it is not possible to remove the release plate from the cured polyurethane. The casting cell is then placed in dry ice to cool the cell to facilitate removal of the release plate. However, the release plate broke after only partial release from the polyurethane.
EXAMPLE II
Trimethylolpropane, polycaprolactone diol, cyclohexanedimethanol and 1-octadecanol are melted and mixed together in the proportions shown below.
______________________________________Component Equivalents Weights______________________________________Trimethylolpropane 0.27 12.7Polycaprolactone diol 0.35 175.0Cyclohexanedimethanol 0.38 29.51-octadecanol 0.014 3.754,4'-methylene-bis-(cyclohexyl isocyanate) 1.03 135.0______________________________________
When the temperature of the mixture of polyols falls to about 57° C., the isocyanate component which is at room temperature is added to the reaction mixture, bringing the temperature to about 44° C. The reaction mixture is then cast into cells and cured as in Example I. When the cells are removed from the oven, all of the release plates can be released while the cell is still hot from the oven, typically about 250° F.
The above examples are offered to illustrate the present invention, the scope of which is defined by the following claims. | A method for obtaining improved release of a polymer from a contacting surface by incorporating a reactive internal release agent in the polymer reaction mixture is disclosed. | 2 |
BACKGROUND—FIELD OF THE INVENTION
This invention “fluid levitating caster integrating load lifting device” applies to the industry concerned with transporting heavy loads from place to place about a floor in an industry where loads levitate upon pressurized fluid casters during transport. More particularly, this invention integrates a fluid levitating caster with a load lifting device to extend fluid caster usefulness to transporting loads with flexible-sagging frames over un-flat floors.
BACKGROUND—DESCRIPTION OF PRIOR ART
In the fluid caster industry of my invention, a load is levitated upon multiple fluid casters attached beneath the load. Fluid casters accomplish the levitation or load lift from fluid pressure confined within a plenum volume beneath the casters. Plenum volume is constrained by the floor upon which the load is moving and the wall of a hollow flexible membrane of the fluid caster.
Most fluid casters used today utilize membranes of such design shape that the footprint area near floor contact is a circle. With these designs, each caster will then lift or levitate a weight equal to the circular area (in square inches for example) multiplied by the plenum fluid pressure (in pounds per square inch for this example).
The levitation or rise height of the load is determined by the designed shape of the caster and particularly the caster membrane. Manufacturers try to design casters with the maximum lift possible for reasons which will soon become apparent. Typically, this lift height is about ⅜ inch for smaller casters 8 inches in diameter and increases to about ¾ inch for larger casters 24 inches in diameter.
This relatively low rise height of ⅜ inch to ¾ inch can be problematic. Several conditions can occur in air bearing transport applications where these low rise heights are insufficient:
Difficulty Flexible-Sagging Load
One example of insufficient caster rise height would be an application where the machine to be moved is large and is flexible. Consider a 6,000 pound machine 10 foot square in size, constructed on a frame fabricated from thin gauge square tubes, normally resting on four legs. If one were to place four air bearings with a rise height of ⅜ inch at four places strategically placed under this machine frame, the casters when inflated will all rise ⅜ inch, but the machine frame may be so compliant (bendable) as to only allow the frame tubing in close proximity above the casters to lift the ⅜ inch. However, the machine frame at locations further away from the casters may not lift at all or very little. One or more machine legs may remain resting on the floor when the casters inflate. If the operator tried to move the machine as described, the dragging leg or legs could damage the machine or floor, or cause enough friction as to not allow the machine to move at all!
Difficulty Un-flat Floor
Another example of insufficient caster rise height would be where the floor is undulated (un-flat) and includes pockets of recessed areas or raised areas that exceed the caster rise heights within an area about the same size as the caster. Visualize another machine again with a very rigid frame resting normally on four legs. Assume four air bearings with a rise height of ⅜ inch are placed strategically under the machine frame. Consider that the floor over which the machine is to be moved has a depression or pocket of size about equal to the caster size and about ½ inch deep. If the operator were to try to move the machine over this depression, one of the casters would lower into the ½ inch depression, the machine over that caster would also lower ½ inch, and one or more machine legs would drag on the floor and cause damage or stop the move!
Difficulty Caster Tilting
A third example of insufficient caster rise height would be combination of the previous two scenarios and involves caster tilting. Conditions of floor flatness and machine frame bending can combine to cause non-parallel-ness between the local floor area (where the caster traverses) and the sagging frame structure to which the caster is attached. If this condition occurs, the caster membrane can be tilted or tipped from one side to the other exceeding the rise height capability of the caster. If this occurs, the membrane can not seal with the floor and the caster will not levitate. It happens, that manufacturers design caster lift heights relative to membrane diameters such that casters must be positioned parallel to the local floor within 2½ degrees for the caster to be able to seal with the floor. This 2½ degree limit can be exceeded by combinations of local machine frame bending and local floor undulation.
It is an object of my invention to integrate the fluid levitating caster with a high rise load lifting device so that the caster functionality problems described above are solved. This high rise caster integration of my invention can have a machine or load lifting capability of several times the ⅜ and ¾ inch membrane lifting heights described. With my invention, practical machine lifting heights exceeding 3 inches for the caster diameters of 8″ to 24″ are quite practical. With my invention “fluid levitating caster integrating load lifting device”, the common operational problems associated with machine frame flexure/bending, undulating floors, and non parallel caster mounting between the floor and load disappear!
Numerous inventors have patented various configurations of fluid levitating casters from about the 1960's and on. However, none of these patents mention the inclusion of a high lift device to add lift beyond the membrane lift height. U.S. Pat. No. 3,756,342 by Burdick, Sep. 15, 1971 shows a very representative fluid caster patent. FIG. 3 shows a (levitation membrane) diaphragm 15 in contact (or near contact) with a floor 12 . The same view also shows a fluid caster platform 10 raised or levitated off floor 12 by an amount equal to diaphragm 15 lift (as caused by automobile inner tube like air inflation). In this patent (as all others in this industry), it is clear that no structure element exists to raise caster platform 10 an amount exceeding diaphragm 15 lift.
Prior Art Method to Achieve High Load Lift
Prior to my invention, if an air caster operator wanted to lift a load higher than the caster membrane lift height (to compensate for load frame flexure, uneven floors, etc.); they would attach an independent load lifting device between each caster mounting plate and the load frame.
A typical example of such a device would be an independent air bag.
Air bags used are smaller in diameter than the caster and so must operate at a greater fluid pressure to lift the same load as the caster beneath. A typical application might use an 8 inch diameter caster operating at 25 pounds per square inch, and an air bag above the caster of 4 inches in diameter. The air bag would have to operate at 100 pounds per square inch pressure to lift the same load as the caster. The dual pressure requirements increases the system complexity significantly.
For one thing, each caster/air bag unit must include two supply hoses.
For another complexity, the air bag can't just rest on top of the caster. Instead, it must be secured to either the load frame above or the caster frame below. The securing design or method will be complex as it must allow flexible vertical motion between the load and the caster, yet constrain the caster center to the center of the load area above. Additionally, the air bag securing method must not add appreciable collapsed height to the caster as it may no longer fit under the load space.
As a final complexity, the caster control console with pressure gauges, valves, regulators, quick connects, etc. (needed to operate the caster/air bag system) is nearly double in complexity over that required for my invention. The system operators have to contend with a larger control console to move around and to manipulate. The purchaser of the relatively awkward caster/air bag system will have to pay significantly extra for the transport system over that of my invention.
SUMMARY OF THE INVENTION
General
My invention integrates a fluid caster with a load lifting device into a single assembly. This invention results in a unique device that not only efficiently levitates with near-friction-less-ness a heavy load for transporting, but can also lift the load a height off the floor far exceeding the rise height of prior art fluid casters alone. The word “caster” will be used to mean “fluid caster” to simplify hereafter discussions.
Loads to be levitated for moving usually rest on four legs contacting the floor—legs cumulatively support the load weight. Four casters are usually placed under the load somewhere near the legs, so as they inflate, the load legs lift off the floor for transport on casters. It is advantageous for casters to lift the load above the floor as far as is possible as some flexible loads can have at least one load leg remaining or dragging on the floor even after prior art casters are inflated.
Multiple conditions can occur when a load leg is not lifted off the floor when prior art casters inflate:
One condition is when the load frame is so compliant as to sag an amount more than the prior art caster rise height. Another condition is when the local floor area over which a prior art caster is moving includes a concave or convex area (about the same size as the caster area) and of a depth or height exceeding the prior art caster rise height. Another condition is when prior art casters are mounted between local load attachment areas and local floor traverse areas at a bias angle exceeding that possible by prior art caster rise heights (about 2½ degrees for commercially available prior art casters).
The high rise feature of my invention “fluid levitating caster integrating load lifting device” can transport loads normally experiencing the above problematic conditions.
A load can have four of my inventions positioned beneath it so as they are pressurized (levitated) the load rises a greater height above the floor then possible with prior art casters. The load lifts all four resting legs off the floor and assumes a position to be transported.
With my invention, a smaller contribution to the load rise height is the rise of the caster membranes. The larger contribution to the load rise height is the rise of the load lifting device on top of the fluid caster. The load lifting device of my invention pushes upward against the bottom of the load, and so raises the load an additional amount.
Bellows Load Lifting Device
One practical design shape of the load lifting device of my invention is a round pie pan shaped flexible bellows held in place on top of the fluid caster frame plate by a clamping ring sealing the bellows lip so as to form a fluid leak proof bellows type chamber. As the bellows load lifting device inflates, it pushes up on the base of the load, and lifts it an amount that is far greater than possible with caster membrane lift alone. The word “bellows” will be used to mean “bellows load lifting device” to simplify hereafter discussions.
The bellows designed lifting area should be made only slightly larger than the caster membrane area so that it can operate at the identical pressure of the caster membrane and still lift the same load as the caster. With this design, the bellows does not require a separate hose, controls, or pressure supply. The bellows can simply be inflated via a conduit or pressure port from the caster membrane plenum. A port passageway through the caster frame plate conveying pressure from the caster membrane plenum to the inside of the bellows will insure that the bellows inflates whenever the caster membrane inflates. Note, if the bellows area were smaller than the membrane footprint area, than the load would rise only the amount of caster membrane lift, but not receive the added rise from the bellows; as the bellows could not exert enough force to lift the load.
Of course, my invention design must include some vertical limit constraining hardware between the bottom load surface and the caster frame plate to keep the load lift operating in the proper range. This vertical constraining hardware must also act as a lateral positioner of the caster frame plate with respect to the load. With proper constraining hardware, my invention will allow the rise height of the load to vary from a rest zero position to a full rise extent possible by the constrained bellows.
Constraining Hardware Shoulder Screws
This constraining hardware can simply comprise four shoulder screws thread anchored into the bottom of the load, but slideable with regard to the caster frame plate. The bottom of the load can then move vertically with respect to the caster frame plate if the corresponding caster frame plate holes are larger than the screw shoulder diameters. This shoulder screw design also constrains the caster frame plate laterally to the load, as the shoulder screws are guiding within the caster frame plate holes. With properly selected shoulder screw lengths/diameters and corresponding caster frame plate hole diameters:
My invention can allow the load to move up and down freely as it is inflated and uninflated to a maximum design height that is far greater than the prior art caster membrane lifting capability. My invention can allow the load to tilt an angle far exceeding 2½ degrees with respect to the floor—2½ degrees being the design limit of commercial prior art casters.
Constraining Hardware—Mounting Plate and Brackets
Another constraining hardware configuration is to add an additional mounting plate above the caster frame plate so that the bellows is sandwiched between the two plates. Brackets can be securely attached to the new mounting plate, but vertically slideable relative to the caster frame plate to the design limits of the bracket. These brackets can slide along the caster frame plate so the caster frame plate is confined laterally. With properly selected bracket design shape/positioning on the mounting plate:
My invention can allow the load to move up and down freely as it is inflated and uninflated to a maximum design height that is far greater than the prior art caster membrane lifting capability. My invention can allow the load to tilt an angle far exceeding 2½ degrees with respect to the floor.
The bellows was discussed only as one example of many possible load lifting devices that maybe integrated with the caster. A second example would be a pressure fluid bag such as that used by emergency rescue teams. The fluid bag can be mounted between the caster body/frame/plate and the load (or another mounting plate which in turn can attach to the load).
My invention vertical motion limit and horizontal constraining hardware discussed above as shoulder screws in one example and formed brackets in another example are not the only hardware devices possible. These were discussed to provide two design methods to provide understanding of achieving free vertical motion of the load above the caster to a limit, while preventing lateral motion of the caster body. Many other design hardware methods can accomplish same: including telescoping tubes, pins siding within slots, and flexible webbing straps to name but only three more.
The important invention objective is to integrate with a prior art fluid caster a practical vertical load lifting device that can lift the load to a far greater height than prior art fluid caster membranes can alone.
My invention “fluid levitating caster integrating load liffing device” is not appreciably larger in physical size, nor in weight, nor in cost than that of prior art fluid casters alone. Therefore cost and space advantages can be realized over alternative methods required when high load lifting is required over non flat floors, with loads having bendable frames, or when casters are mounted non-parallel to the load.
The original problem my invention was attempting to solve was to add increased load lift to prior art casters with low cost, and low uninflated thickness so it can be positioned under loads resting only a nominal distance above the floor.
Unexpected Angular Operational Benefit
However during my invention development, two unexpected advantages were realized: First, it was learned the invention became useful in situations where the caster is angled relative to the load (or where the floor slopes are at an angle relative to the load). In these situations, if this angle exceeded about 2½ degrees, prior art casters would not operate/inflate. However, my invention hardware designs between the load and the caster frame plate allow the caster to tilt relative to the load at an angle far exceeding the here-to-fore 2½ degree practical limit. This angular operating feature/benefit of my invention opens to the industry the fluid levitated transport of loads using casters in situations not possible with prior art casters.
Unexpected Dampening Benefit
The second unexpected advantage of my invention is that the bellows chamber in direct pressure communication with the caster levitation chamber provides a most effective vibration or hopping damping correction to the caster. This unstable hopping characteristic of fluid casters is well understood by caster designers, and so, is the solution of adding the largest possible fluid reservoir in pressure communication with the caster levitation chamber. The high lift device of my invention “fluid levitating caster integrating load lifting device” includes just such a bellows chamber reservoir and unexpectedly solves the hopping problem inherent in fluid casters without having to add an external costly, and space consuming reservoir.
The prior art U.S. Pat. No. 3,756,342 by Burdick, Sep. 15, 1971 identifies this prior art solution to the inherent caster hopping problem. This Burdick U.S. Pat. No. 3,756,342 patent at about line 48 of column 2 of the specification refers to a dampening chamber 32 in pressure connection with the caster annular zone 25 through a damping opening 36 . Damping chamber 32 purpose is described as serving to dampen or smooth out surges in air pressure within caster annular zone 25 .
The bellows or similar pressure chambered high rise device of my invention “fluid levitating caster integrating load lifting device” serves the exact same damping function of the Burdick U.S. Pat. No. 3,756,342 damping chamber 32 .
By way of example, my invention is illustrated herein by the accompanying drawings, wherein:
DRAWING FIGURES
In the drawings, closely related components from different figure assemblies have the same number but different alphabetic suffixes.
FIG. 1 is a perspective view of a prior art fluid caster
FIG. 2 shows a fragmentary sectional elevation view of FIG. 1 taken as suggested by lines 2 — 2 shown placed between a floor and load to be levitated and moved.
FIG. 3 is a perspective view of a fluid levitating caster integrated with a load lifting device—where lift device vertical motion is constrained by shoulder screws.
FIG. 4 shows a sectional elevation view taken as suggested by lines 4 — 4 of FIG. 3 shown placed between floor and load to be levitated and moved—where caster is shown inflated.
FIG. 5 shows a sectional elevation view of the assembly of FIG. 4 —where caster is shown uninflated.
FIG. 6 shows a sectional elevation view of the assembly of FIG. 4 —where caster is shown inflated and floor is not parallel to the load.
FIG. 7 shows another embodiment of a fluid levitating caster integrated with a load lifting device—where lift device vertical motion is constrained by slideable brackets.
FIG. 8 shows a sectional elevation view taken as suggested by lines 8 — 8 of FIG. 7 shown placed between floor and load to be levitated and moved
FIG. 9 shows another embodiment of a fluid levitating caster integrated with a load lifting device—where lift device vertical motion is constrained by webbing straps.
FIG. 10 shows a sectional elevation view taken as suggested by lines 10 — 10 of FIG. 9 shown placed between floor and load to be levitated and moved.
REFERENCE NUMERALS IN DRAWINGS
11 & 11 a membrane
12 & 12 a caster body
13 & 13 a conduit
14 & 14 a caster plate
15 & 15 a plenum
16 mounting plate
17 load
18 floor
19 clamp ring
20 ring screw
21 bellows port
22 bellows
23 & 23 a mounting shoulder screws
24 positioning brackets
25 bracket screws
26 mounting holes
27 & 27 a levitation chamber
28 webbing straps
29 matching holes
30 assembly
31 invention A
32 invention B
33 invention C
MR membrane rise height
ER extra rise height
AR angular tilt
DESCRIPTION OF THE PREFERRED EMBODIMENTS
1. Description of a Prior Art Embodiment
The view of FIG. 1 shows a prior art fluid caster construction referred to as an assembly 30 . Components of assembly 30 will be referred to as the same numbers with an “a” suffix as components later used in my invention descriptions to help comparative understanding. Assembly 30 includes a caster body 12 a , a levitation membrane 11 a , a mounting caster plate 14 a , and a pressure inlet conduit 13 a . Referring now to the view of FIG. 2 , assembly 30 is shown resting on the surface of a floor 18 . Positioned above assembly 30 is a load 17 to be levitated and moved. Load 17 is shown fastened to caster plate 14 a with mounting shoulder screws 23 a . Assembly 30 is shown inflated in that load 17 rises a height above floor 18 an amount referred to as a membrane rise height MR. Levitation is accomplished whenever pressurized fluid is conveyed into conduit 13 a , which pressurizes a sealed levitation chamber 27 a above membrane 11 a and within a membrane plenum 15 a . Note the total load 17 lift is only that distance provided by membrane 11 a inflation—membrane rise height MR.
2. The Invention A Embodiment With Bellows High Lift and Shoulder Screw Attachment to Load
The view of FIG. 3 shows an embodiment of my invention “fluid levitating caster integrating load lifting device” referred to as an invention A 31 . Invention A 31 includes a caster body 12 , a levitation membrane 11 , a mounting caster plate 14 , and a pressure inlet conduit 13 .
Referring now to the view of FIG. 4 , invention A 31 is shown resting on surface of floor 18 . Positioned above invention A 31 is load 17 to be levitated and moved. Load 17 is shown fastened to caster plate 14 with a series of long mounting shoulder screws 23 . Invention A 31 is shown inflated in that caster body 12 rises a height above floor 18 an amount equal to membrane rise height MR. Levitation is accomplished whenever pressurized fluid is conveyed into conduit 13 , which pressurizes a levitation chamber 27 above membrane 11 and within plenum 15 . So far invention A 31 is nearly identical in design and function to prior art caster assembly 30 of FIG. 1 .
Mounting plate 16 thickness found to work well to attach with high rise lifting bellows 22 is ¼ inch and made from a stiffer aluminum alloy such as 6061 T6. However, thicker plates should work as well as or better to the limit of fitting under the load space available.
However, attached to the top of invention A 31 are additional extra lifting components: These include a pie plate shaped bellows 22 , with a clamp ring 19 and an annular series of ring screws 20 . Ring screws 20 and clamp ring 19 seal bellows 22 with the top surface of caster plate 14 so bellows 22 confines an inflatable chamber within. Included in invention A 31 is a bellows port 21 which conveys pressurized fluid from a caster levitation chamber 27 to bellows 22 . In this manner, whenever caster membrane 11 is pressurized, bellows 22 is also pressurized.
The area of bellows 22 in contact with load 17 is designed to be slightly larger than the contact area of membrane 11 with floor 18 . This area selection insures that when enough pressure is applied within membrane 11 to levitate load 17 , bellows 22 will also lift load an extra height referred as an extra rise height ER.
A flexible thin material that has been found to work well for fabricating bellows 22 is polyurethane reinforced with cotton cloth weave. An effective hardness for the polyurethane can be 65 shore A, as it is flexible enough to seal well under clamp ring 19 and ring screws 20 . A good material thickness is 0.05 inches. Bellows 22 lip width to affect a leak proof seal is around ⅝ inch. The molding can be easily performed by most commercial rubber molding houses such as Advanced Urethane Solutions, 3912 Tryon Courthouse Road, Cherryville, N.C. 28021.
Mounting shoulder screws 23 slip within caster plate 14 , and thread within the bottom of load 17 . In this way, mounting shoulder screws 23 allow bellows 22 to lift load 17 vertically while constraining laterally to extra rise height ER limit as determined by the shoulder length of mounting shoulder screws 23 .
Shoulder screws 23 used in the first constraining mount configuration are well known fasteners by machinists and machine designers. It has been found that 5/16 inch shoulder diameter provides good strength for lateral caster plate 14 guidance. They can be purchased from catalog sales from McMaster Carr Supply Company of Dayton, N.J. 08810.
Note the total load 17 lift is the sum of membrane rise height MR plus extra rise height ER. Load 17 , with invention A 31 , can be lifted to far greater heights above floor 18 (easily several times membrane rise height MR of prior art caster assembly 30 of FIG. 1 ).
Invention A 31 is shown in FIG. 5 uninflated. Membrane 11 is collapsed against floor 18 and there is no membrane rise height MR. High lift bellows 22 is collapsed between load 17 and caster plate 14 , with load 17 resting upon clamp ring 19 . Mounting shoulder screws 23 are shown slipped to their fullest extent toward floor 18 .
Invention A 31 is shown in FIG. 6 with an angular tilt AR separation shown between load 17 and caster body 12 . The angularity is possible simply by using enlarged holes through caster plate 14 through which slide mounting shoulder screws 23 . Note angular tilt AR magnitude is greater than maximum possible membrane rise height MR With invention A 31 , load 17 can be tilted with respect to local floor 18 area to a far greater amount than is possible with prior art caster assembly 30 of FIG. 1 .
3. The Invention B Embodiment With Bellows High Lift and Bracket With Mounting Plate Attachment to Load
The view of FIG. 7 shows an embodiment of my invention “fluid levitating caster integrating load liffing device” referred to as an invention B 32 . Invention B 32 includes caster body 12 , levitation membrane 11 , caster plate 14 , and pressure inlet conduit 13 . Invention B 32 includes an extra mounting plate 16 above bellows 22 . Mounting plate 16 has attached to its periphery a series of positioning brackets 24 secured with a series of bracket screws 25 rigidly securing positioning brackets 24 and threaded into mounting plate 16 . Positioning brackets 24 are positioned and shaped so that they allow vertical travel between caster plate 14 and mounting plate 16 as bellows 22 lifts and contracts. Yet positioning brackets 24 constrain lateral motion between mounting plate 16 and caster plate 14 . Note further that the design and location of positioning brackets 24 with respect to caster plate 14 will allow angular tilt AR similar to that shown in FIG. 6 .
Brackets 24 used in the second constraining mount configuration can be made of a formed steel alloys, with a thickness exceeding about 0.10 inch, and a width exceeding about 1 inch. These approximate minimum sizes provide good lateral caster plate 14 guidance.
Referring to the view of FIG. 8 , caster invention B 32 is shown resting on surface of floor 18 . Positioned above invention B 32 attached to mounting plate 16 with screws (not shown) through a series of mounting holes 26 (shown in FIG. 7 ) is load 17 to be levitated and moved. As with invention A 31 of FIGS. 3–6 , attached to the top of invention B 32 are the extra lifting components: bellows 22 , clamp ring 19 ring screws 20 . Invention B 32 is shown levitated in that load 17 rises a height above floor 18 an amount equal to membrane rise height MR plus extra rise height ER.
4. The Invention C Embodiment With Bellows High Lift and Webbing Strans With Mounting Plate Attachment to Load
The view of FIG. 9 shows an embodiment of applicant's invention “fluid levitating caster integrating load lifting device” referred to as an invention C 33 . Invention C 33 includes caster body 12 , levitation membrane 11 , caster plate 14 , and pressure inlet conduit 13 . Invention C 33 includes an extra mounting plate 16 above bellows 22 . Mounting plate 16 has attached to its periphery a series of webbing straps 28 shown in this example laced through matching holes 29 in both mounting plate 16 and caster plate 14 . Webbing strap 28 length is selected so they allow desired vertical travel between caster plate 14 and mounting plate 16 as the bellows 22 lifts and contracts. Yet webbing strans 28 constrain excessive lateral motion between mounting plate 16 and caster plate 14 . Note further that the design and location of webbing straps 28 with respect to caster plate 14 will facilitate angular tilt AR similar to that shown in FIG. 6 .
Webbing Straps 28 used in this constraining mount configuration can be made of flexible/bendable braided steel wires strong enough to withstand the maximum bellows 22 lift force possible. Alternately, polyester flexible multi-strand cord or woven fabric again strona enough to withstand the maximum bellows 22 lift force possible can be used for constructing webbing straps 28 . The two loose ends of the webbing straps 28 can be secured to the mounting plate 16 with screws (not shown). McMaster Carr Company at 473 Ridge Road. Dayton, N.J. 08810 offers a wide selection of steel braided, multi-strand cord, and fabrics both strong enough and flexible enough for this application.
Referring to the view of FIG. 10 , invention C 33 is shown resting on surface of floor 18 . Laced through mounting plate 16 positioned above invention C 33 are shown multiple webbing straps 28 . Correspondingly, same webbing straps 28 are shown laced through caster plate 14 . Shown above the mounting plate 16 is load 17 to be levitated and moved. As with invention A 31 of FIGS. 3–6 , attached to the top of invention C 33 are the extra lifting components: bellows 22 , clamp ring 19 , ring screws 20 . Invention C 33 is shown levitated in that load 17 rises a height above floor 18 an amount equal to membrane rise height MR plus extra rise height ER. | A fluid levitating caster lifts a heavy load “( 17 )” off a floor “( 18 )” with near friction-less-ness for transport has integrated a load lifting device. This extra rise height “(ER)” lifting feature accommodates moving loads “( 17 )” which have flexible-sagging frames, over uneven floors “( 18 )”, and which have frames that are not parallel to floor “( 18 )”. An inflatable bellows “( 22 )” design of the load lifting device receives its pressurization from fluid levitating caster, and additionally serves as a dampening reservoir to reduce hopping-pressure surges inherent in fluid levitating casters. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is generally related to hydrocarbon well stimulation, and is more particularly directed to a method for designing matrix treatment, or generally any treatment with a fluid that will react with the reservoir minerals or with chemicals resulting for instance from a previous treatment. The invention is particularly useful for designing acid treatment such as for instance mud acid treatments in sandstone reservoirs.
[0003] 2. Discussion of the Prior Art
[0004] Matrix acidizing is among the oldest well stimulation techniques. It is applied to sandstone formations to remove near-wellbore damage, which may have been caused by drilling, completion, production, or workover operations. Matrix acidizing is accomplished by injecting a mixture of aids (typically hydrofluoric and hydrochloric acids) to dissolve materials that impair well production, as a rule designated as near-wellbore damages.
[0005] Matrix treatments ma sandstone reservoirs have evolved considerably since the first mud acid treatment in the 1930s. Treatment fluid recipes have become increasingly complex. Several additives are now routinely used and organic acids are frequently used in high temperature formations to avoid precipitation reactions. Chelating agents are often added to avoid precipitation in formations with high carbonate content.
[0006] Substantial production improvements can be achieved by this type of well stimulation technique if treatments are engineered properly. However, matrix treatments are also often a main contributor to reservoir damages. Indeed, the side reactions that occur in almost all mud acid treatments, lead to the formation of precipitates. Precipitates plug pore spaces and reduce permeability and can therefore adversely affect acid treatments if precipitates deposit near the wellbore. Far from the well precipitates are considered to have negligible effect. Moreover, recent studies have made the industry wary of damage due to secondary and tertiary reactions. Accurate prediction of the effectiveness of a matrix treatment involves calculation of the rates of the dissolution and re-precipitation reactions of minerals because the rates dictate where precipitates will be deposited in the reservoir.
[0007] Moreover, sandstone mineralogy is quite complex and acid/mineral compatibility as well as acid/crude oil compatibility is often an issue. At present, there is a lack of tools that can predict accurately the reactivity of acids with clays, and consequently, there are treatments currently in practice that use empirical rules—or at the opposite extreme, rely on extensive costly and time-consuming laboratory testing.
[0008] Beyond the treatment fluid selection, the pumping schedule is also a crucial parameter. In The Stimulation Treatment Pressure Record - An Overlooked Formation Evaluation Tool, by H. O. McLeod and A. W. Coulter, JPT, 1969, p. 952-960, a technique is described wherein each injection stage or shut-in during the treatment is considered as a short individual well test. The transient reservoir pressure response to the injection of fluids is analyzed and interpreted to determine the conditions of the wellbore skin and formation transmissibility.
[0009] In New Method Proves Value of Stimulation Planning, Oil & Gas Journal, V 77, NO 47, PP 154-160, Nov. 19, 1979, G. Paccaloni proposes a method based on the instantaneous pressure and injection rate values to compute the skin factor at any given time during the treatment. Comparison is made with standard curves calculated for fixed values of skin effect to evaluate skin effect evolution during treatment. Standard curves are generated using Darcy's equations for steady state, single phase and radial horizontal flow in reservoirs.
[0010] A technique presented by Prouvost and Economides enables continuous calculation of the skin effect factor during the course of the treatment and accounts for transient response, see Real - time Evaluation of Matrix Acidizing, Pet. Sci, and Eng., 1987, p.145-154, and Applications of Real - time Matrix Acidizing Evaluation Method, SPE 17156, SPE Production Engineering, 1987, 4, No. 6, 401-407. This technique is based on a continuous comparison of the measured and presumed good reservoir description including the type of model and well and reservoir variables of the subject well.
[0011] It is also known from U.S. Pat. No. 5,431,227 to provide a method for matrix stimulation field monitoring, optimization and post-job evaluation of matrix treatments based on calculated and measured bottom hole pressure used in a step rate test to estimate the damage skin.
[0012] A number of sandstone acidizing models have been presented in the literature aiming at computing changes in porosity resulting from the dissolution and precipitation of minerals.
[0013] In the lumped mineral models, the complex sandstone mineralogy is lumped into characteristic minerals and an average reaction rate for these minerals is determined from core tests. In two mineral models the sandstone minerals are lumped into fast- and slow-reacting groups on the basis of their reactivity with HF. Two mineral models do not account for precipitation reactions. A three mineral lumped model has also been proposed in S. L. Bryant, SPE 22855, An Improved Model of Mud Acid/Sandstone Acidizing, in SPE Annual Technical Conference and Exhibition, 1991, Dallas. The third mineral accounts for the precipitation of amorphous silica. Disadvantages of lumped mineral models are that they do not allow for equilibrium reactions to be modeled and need to be carefully calibrated to the treatment condition and formation of interest. Therefore, these models are not applicable to fluids systems containing weak acids (e.g. most organic acids) and chelating agents and are not reliable outside the calibrated region.
[0014] The equilibrium approximation is another approximation that is frequently used for the design of matrix treatments. This model has been presented in Walsh, M. P., L. W. Lake, and R. S. Schechter, SPE 10625, A Description of Chemical Precipitation Mechanisms and Their Role in Formation Damage During Stimulation by Hydrofluoric Acid, in SPE International Symposium on Oilfield and Geothermal Chemistry, 1982, Dallas. In the equilibrium approximation it is assumed that the reactions are much faster than the contact time of the minerals with the acids. The equilibrium constants for the reactions are usually better known than the rate constants, so large reaction sets can be included and complex sandstone mineralogy can be accounted for without speculating on the reactions and rate laws as is necessary in the lumped mineral approach. Unfortunately, the assumption that the reactions are much faster than the contact time is not valid for the injection rates used in most acid treatments and thus the equilibrium approach is useful only as an indicator for precipitation. The question that must be answered for a successful design is not if but where precipitation will occur. An equilibrium model alone with no time dependence cannot answer this question.
[0015] To address this discrepancy in the equilibrium models, partial local equilibrium models have been proposed and first described in Sevougian, S. D., L. W. Lake, and R. S. Schechter, KGEOFLOW: A New Reactive Transport Simulator for Sandstone Matrix Acidizing, SPE Production & Facilities, 1995: p. 13-19 and in Li, Y., J. D. Fambrough, and C. T. Montgomery, SPE 39420, Mathematical Modeling of Secondary Precipitation from Sandstone Acidizing, SPE International Symposium on Formation Damage Control, 1998, Lafayette. The partial equilibrium approach combines the kinetic and equilibrium approaches. Slow reactions are modeled with a kinetic model, and an equilibrium model is used for fast reactions. This computation scheme enables comprehensive and flexible modeling of sandstone acidizing, but traditionally suffered from several disadvantages. First, accurate computation of the activity coefficients for high acidic and high ionic strength solutions is difficult. Second, due to inefficient numerical algorithms numerical convergence was a frequent problem. Therefore, only 1-2 precipitated mineral species could be practically simulated. Third, only a limited thermodynamic data was available. Hence, simulations for hot reservoirs and with nontraditional fluid systems were not possible.
[0016] The previous models are applicable to a limited range of temperatures, injection rates and mineral composition. So yet, despite the important risk of damaging a reservoir, no satisfactory method for modeling matrix treatments over a much broader range of these variables, to make the model more reliable for extrapolating laboratory data to field conditions.
[0017] This failure of the existing models is all the more critical that treatment fluid recipes have become increasingly complex. Several additives are now routinely added, organic acids are frequently used in high temperature formations to avoid precipitation reactions and chelating agents are often added to avoid precipitation in formations with high carbonate content.
SUMMARY OF THE INVENTION
[0018] The subject invention is directed to a method for designing matrix treatments, and more particularly, for stimulation with reactive fluid in sandstone formations, even though the invention extends to other areas such as carbonate acidizing, scale inhibition and related fields. In particular, according to a first embodiment, the invention relates to a method for selecting the optimal treatment wherein reservoir characteristics including reservoir minerals are obtained and a treatment fluid comprising a mixture of chemical species is designed to further select a subset of chemical reactions that can occur between the reservoir minerals and the treatment fluid the reaction kinetic and equilibrium data on the minerals and chemical species of interests, and depending on the predicted damages consecutive to those reactions, the stimulation treatment is adjusted to optimize the results. In other words, the invention proposes a virtual chemical laboratory that makes it possible to simulate a large number of laboratory tests.
[0019] In a second embodiment of the invention, the method further includes modeling a reservoir core having a length, a diameter and a permeability so that the invention makes it possible to simulate core tests. The invention also provides a way to simulate sequential treatments where successions of treatment fluids are injected at specific rates.
[0020] In a third embodiment of the invention, the method further includes scaling up the treatment to a reservoir using a mathematical model to predict damages resulting from the treatment. In a most preferred embodiment, the invention includes selecting a treatment, carrying out the treatment on a well while real time damage are computed based on bottomhole pressure and injection rate and simultaneously, performing a simulation scaled up to the reservoir to compare the predicted damages and the computed damages and adjusting the treatment if required.
[0021] In the preferred embodiments of the invention, the three flow geometries have been implemented: (1) batch, (2) core and (3) reservoir geometries. The batch flow geometry approximates the reactions occurring in a flask or a beaker, the core flow geometry approximates linear flow in cores such as that in laboratory core flooding experiments, and the reservoir flow geometry approximates flow in a single layer, radially symmetric reservoir. The batch and core flow geometries provide a means for validating the mathematical model, so that the predictions for the reservoir can be made with more confidence.
[0022] The model generated by the method of the subject invention can facilitate optimization of matrix treatments by providing a rapid quantitative evaluation of various treatment strategies for a formation. Stimulation with non-traditional fluid recipes containing mixtures of inorganic and organic acids, and chelating agents can be readily computed. The computed values can then be used in an economic model to justify the additional costs associated with the use of the non-traditional fluids. Apart from optimizing matrix treatments, the method of the subject invention can also be used as a development tool for new fluid systems, as a tool for prediction and removal of inorganic scale and for fluid compatibility testing such as that required in waterflooding projects.
[0023] The method of the subject invention combines a geochemical simulator to an extensive database of thermodynamic properties of aqueous chemical species and minerals. The subject invention overcomes many limitations of previous simulators. Chemical equilibrium calculations can be performed between any number of minerals and aqueous solutions, whereas previous simulators were limited to only one or two precipitated minerals. Additionally, any number of kinetically controlled reactions can be simulated with user-defined kinetics.
[0024] The modeling method of the subject invention is a finite-difference geochemical simulator capable of modeling kinetic and/or equilibrium controlled reactions in various flow geometries. The mathematical formulation provides the capability to model an arbitrary combination of equilibrium and kinetic reactions involving an arbitrary combination of equilibrium and kinetic reactions involving an arbitrary number of chemical species. This flexibility allows the simulation model to act as a pure kinetic model if no equilibrium are specified or as a pure equilibrium model if both kinetic and equilibrium reactions are specified. A semi-implicit numerical scheme is used for integration in time for kinetic reactions. This scheme provides greater numerical stability compared to explicit schemes, especially at high temperature. A Gibbs free energy minimization algorithm with optimized stoichiometry is used in computing chemical equilibrium between aqueous species and minerals. Base specie switching is implemented to improve convergence. The resulting algorithm for chemical equilibrium calculation is of greater numerical stability and is more efficient than prior art algorithms based on a non-stoichiometric approach.
[0025] The treatment design preferably includes variables such as fluid type, composition, volume, pumping sequence and injection rates. A database is used to get the reaction kinetics data. If insufficient data is available, laboratory experiments may be conducted, preferably using multiple linear core flow tests for a range of injection rates.
[0026] The reservoir characteristics typically include mineralogy data, permeability and preferably, an estimate of the quantity and depth of damage such as scales, fines migration or drilling-related damages including the initial damage skin. This estimate can be made for instance based on nodal analysis or available mud and resistivity logs. The reservoir characteristics may be stored in a database and if not already available, are obtained by geochemical logging or from core analysis and further stored in the database for further use.
[0027] The model is preferably calibrated with data including effluent analysis and permeability evolution (including predicted damages). Sensitivity analysis may be also performed to optimize the design variables and select improved treatment design.
[0028] Once an optimized design has been selected, the execution of the treatment can begin and damage skin can be computed on a real time basis. This allows a comparison with the predicted damages and, if appropriate, adjustment of the treatment.
[0029] Specifically, the invention comprises data collection, design optimization, execution and evaluation. In the execution phase, the damage is computed in real time from either calculated or measured values of bottomhole pressure and injection rate. It can then be compared to the computed damage skin with that predicted by the mathematical model. The model can thereafter be refined by better estimates for type, quantity and depth of damage to match the measured values and, if needed, appropriate changes to the treatment design are performed.
[0030] Post treatment data, such as flowback analysis, production data and production logs, are used to further refine the mathematical model and the estimates of damage depth and quantity. The treatment data can finally be uploaded into the database so it can be used in improving future treatment designs.
[0031] The method of the subject invention facilitates treatment design with the methodology described above. This can be implemented with a mathematical model and databases. The mathematical model may comprise the following components:
[0032] 1. Algorithm for automatic selection of the various applicable chemical reactions for the defined system of fluids and minerals
[0033] 2. Modeling of organic acids and chelating agent chemistry for sandstone acidizing
[0034] 3. Algorithm for scale up from core to reservoir
[0035] 4. Modeling of multiple precipitates
[0036] The mathematical model can be extended later to other processes such as carbonate acidizing, scale inhibition, or other mechanisms that involve fluid/reservoir interaction.
[0037] According to a preferred embodiment, the method of the subject invention incorporates extensive databases of minerals, chemical reactions, fluids and reservoirs in order to feed the mathematical model with accurate geological, physical and reactivity data, thereby ensuring the success of the process. Users preferably have the ability to create new components (fluids, minerals, reactions) and add them to the database for future use. This allows continued expansion of the methodology of the subject invention to new systems and new processes. In accordance with the teachings of the subject invention, chemical equilibrium calculations can be performed between any number of minerals and aqueous solutions.
[0038] In the preferred embodiment of the invention, the essential steps are stored on a CD-ROM device. In another preferred embodiment, the method/process is downloadable from a network server, or an internet web page. Moreover, the present invention can be subsumed using a software developed to assist acid treatments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] [0039]FIG. 1 shows a comparison of the measured effluent concentration of HF, Al, and Si with those predicted by the model of the present invention.
[0040] [0040]FIG. 2 are graphs providing a snapshot of the reservoir at the end of the mud acid stage.
[0041] [0041]FIG. 3 compares the results for different injection rates and a different mud acid formulation.
[0042] [0042]FIG. 4 shows the result of the treatment if the reservoir had been damaged with a mineral similar to kaolinite.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] The methods of the subject invention provide a virtual laboratory geochemical simulator for well simulating by permitting and supporting scaled laboratory modeling to be scaled to reservoir adaptability. The laboratory experiments validate the model and permit scaling up to reservoir level with precision and efficiency. The fundamental tools provide: (1) a reaction model, (2) analysis of the model, (3) testing at the model level, (4) validation, and (5) scale-up to reservoir. This permits laboratory review and modeling of formation damage with predictabilaty, accurate confirmation and ready and efficient adjustability. Specifically, the methods of the subject invention permit laboratory design, execution and evaluation prior to reservoir application greatly increasing the efficiency of the process.
[0044] The numerical model of the present invention is a finite-difference geochemical simulator capable of modeling kinetic and/or equilibrium controlled reactions (i.e. partial local equilibrium reaction moe) in various flow geometries. The mathematical formulation provides the capability to model an arbitrary combination of equilibrium and kinetic reactions involving an arbitrary number of chemical species. This flexibility in the mathematical formulation allows it to act as a pure kinetic model if no equilibrium reactions are specified, or a pure equilibrium model if no kinetic reactions are specified, or as a partial equilibrium model if both kinetic an equilibrium reactions are specified. A semi-implicit numerical scheme is used for integration in time for kinetic reactions. This scheme provided greater numerical stability compared to explicit schemes, especially at high temperature. A Gibbs free energy minimization algorithm with optimized stoichiometry is used in computing chemical equilibrium between aqueous species and minerals. Base specie switching is preferably implemented to improve convergence. The resulting algorithm for chemical equilibrium calculation was found to be much more numerically stable and computationally efficient than algorithms based on the nonstoichiometric approach.
[0045] In this embodiment, three flow geometries are implemented in the simulator. These are batch, core and reservoir flow geometries. The batch flow geometry approximates reactions occurring in a flask or a beaker, the core flow geometry approximates linear flow in cores such as that in laboratory core flooding experiments, and the reservoir flow geometry approximates flow in a single layer, radially symmetric reservoir. The batch and core flow geometries provide a means for validating the mathematical model, so that the predictions for the reservoir can be made we more confidence. For example, the geochemical simulator can be validated with measured effluent ion concentrations and the permeability evolution from laboratory core flow experiments, prior to making predictions for the reservoir.
[0046] Typical matrix stimulation fluids are extremely non-ideal. The ideal solution assumption usually breaks down for salt concentrations higher than that of fresh water. Activity coefficients capture deviations from ideal solution behavior, and are therefore crucial for accurate modeling of kinetic and equilibrium reactions in concentrated electrolyte solutions (e.g. matrix treatment fluids containing acids and brines).
[0047] The following symbols and their definitions are used throughout this application and the appended claims:
[0048] A γ =electrostatic Debye-Hückel parameter
[0049] A j, s =specific reactive surface area of mineral j (m 2 /kg)
[0050] A A , A B , A C , A W =activity of aqueous species A, B, C and water (kgmole/m3)
[0051] a i (P, T), a i, P t T t =ionic diameter, ionic diameter at reference temperature and pressure (Å)
[0052] a i, 1-4 =parameter in Helgeson EOS for aqueous species
[0053] b i =salting-out parameter for specie i (kg/mol)
[0054] B γ =electrostatic Debye-Hückel parameter
[0055] {dot over (B)}(T)=deviation function describing the departure of the mean ionic activity coefficient of an electrolyte from that predicted by Debye-Hückel expression (kg/mol)
[0056] b NaCl =electrostatic salvation parameter for NaCl (kg/J)
[0057] b Na+Cl− =short-range interaction parameter for NaCl (kg/mol)
[0058] C p, i =heat capacity of specie i at constant pressure (J/mol-K)
[0059] C 1-2 =parameter in variable reaction order kinetic model (1/K)
[0060] c i, 1-2 =parameters in Helgeson EOS for aqueous species
[0061] E a , E′ a =activation energy (J/mol)
[0062] f(T)=temperature function in variable reaction order kinetic model
[0063] G i, P, T t o G i, P t , T t o =standard molal Gibbs free energy of formation at subscripted temperature and pressure (J/mol)
[0064] g(P, T)=pressure and temperature dependent solvent function (Å)
[0065] H i o =standard molal enthalpy of formation (J/mol)
[0066] I=ionic strength of solution (mol/kg)
[0067] K=equilibrium constant
[0068] K″ 0 , k″ 0 =pre-exponential factors
[0069] k 0 , k=initial and final permeability (mD)
[0070] M j, 0 , M j =initial and final volume fraction of mineral j (m3/m3)
[0071] M j, W =molecular weight of mineral j (g/mol)
[0072] [M j ]=concentration of mineral j (kgmol/m 3 )
[0073] m i , {right arrow over (m)}=molality of specie i and vector of molalities (mol/kg solvent)
[0074] P, P r =pressure (bar) and standard pressure (1 bar)
[0075] P inj =bottomhole injection pressure (bar)
[0076] P res =reservoir pressure at out boundary (bar)
[0077] R=gas constant (=8.314 J/mol-K)
[0078] rate=volumetric reaction rate (kg mole mineral/m 3 sec)
[0079] S i, P r , T r o =standard molal entropy of formation at P r and T r (J/mol-K)
[0080] T, T r =temperature (K) and standard temperature (298.15 K)
[0081] V P r, T r o =standard molal volume at P r and T r (m 3 /mol)
[0082] x, y, z=reaction order with respect to species A, B and C
[0083] Y P r , T r =electrostatic Born function at P r and T r
[0084] Z, Z P r , T r =electrostatic Born function at P and T, and at P r and T r
[0085] z i =ionic charge of specie i
[0086] β i, 0-7 =heat capacity parameter for specie i
[0087] γ i =activity coefficient for specie i
[0088] δ j =Labrid parameter for mineral j
[0089] ξ i, 1-5 =chemical potential parameters for specie i
[0090] η=constant (=694630.393 ÅJ/mol)
[0091] Θ=constant (=298 K)
[0092] θ i, 1-3 =Maier-Kelly heat capacity coefficients
[0093] μ i , μ j 0 =chemical potential and standard chemical potential of specie i (J/mol)
[0094] μ w , μ w 0 =chemical potential and standard chemical potential of water (J/mol)
[0095] ν i =stoechiometric coefficient of specie i (positive for products, negative for reactants)
[0096] φ 0 =initial porosity
[0097] Ψ=constant (=2600 bars)
[0098] Ω=moles of water/kg
[0099] ω i, ω i, Pr, Tr =Born coefficient of specie i at P and T, and at P r and T r (J/mol)
[0100] Activity coefficient models available in a typical prior art version of the simulator are shown in Table 1:
TABLE 1 Activity Coefficient Models Extended Debye- Hückel log γ i = ( - z i 2 A γ I 1 + B γ a i I ) + Γ Davies log γ i = - z i 2 A γ ( I 1 + I - 0.3 I ) B-Dot log γ i = ( - z i 2 A γ I 1 + B γ a i ( P , T ) I ) + Γ + B . ( T ) I a i ( P , T ) = a i , P r , T r + 2 z i g ( P , T ) HFK log γ i = ( - z i 2 A γ I 1 + B γ a i ( P , T ) I ) + Γ + ( 2 η z i 2 a i ( P , T ) b NaCl + b Na + Cl - - 0.19 ( z i - 1 ) ) I a i ( P , T ) = a i , P r , T r + 2 z i g ( P , T ) Neutral species log γ i = b i I Water log A w = 1 Ω ( - ∑ m i ln 10 + 2 3 A γ I 1.5 σ - B . ( T ) I 2 ) σ = 3 ( 4 B γ I ) 3 ( 1 + 4 B γ I - 1 1 + 4 B γ I - 2 ln ( 1 + 4 B γ I ) )
[0101] The Extended Debye-Hückel uses a species dependent ionic size. The Davies model (in Davies, C. W., Ion Association. 1962, London: Butterworths) uses a constant ionic size and requires only the specie charge. The B-Dot model (in Helgeson, H. C., Thermodynamic of Hydrothermal Systems at Elevated Temperatures and Pressures, American Journal of Science, 1969. 267 (Summer): p. 729-804) captures the temperature dependence of activity coefficients. The HKF model is described in Helgeson, H. C., D. H. Kirham, and G. Flowers, Theoretical Prediction of the Thermodynamic Behavior of Aqueous Electrolytes at High Pressures and Temperatures: IV. Calculation of Activity Coefficients, Osmotic Coefficients, and Apparent Molal and Standard and Relative Partial Molal Properties to 600° C. and 5 KB, Amer. J. Sci., 1981. 281: p. 1249-1516. Activity coefficients in this model are computed by specifying the specie charge and ion-size under standard conditions. All other parameters in the equation are computed internally in the simulator. For aqueous species for which ion-size data is not available, an estimate for ion-size from species with similar charge and atomic structure and use of the HKF model gives a reasonable representation for most stimulation.
[0102] For neutral species in aqueous solutions the salting out model is used. The value of b i in this model is typically zero or very close to zero for most species. Therefore for species for which this parameter is not known a value of zero is usually accurate enough for most simulations.
[0103] Once the mineralogy and treatment fluids are specified, the system may automatically select the applicable kinetic reactions and presents them to the user for review. The user may then accept the default reactions, add new reactions or modify the kinetics of the default reactions. The standard database provided with the program contains data for common matrix reactions. New reactions may be added by specifying the reaction stoichiometry and kinetic rate law parameters. Table 2 lists kinetic rate laws preferably implemented:
TABLE 2 Reaction Rate Law Models Reaction Rate Law Equation Arrhenius Surface rate = A j,s M j,w [M j ]k 0 ″e −E a /RT A A x A B y A C z Catalytic rate = A j,s M j,w [M j ]k 0 ″e −E a /RT [1 + K 0 ″e −E a /RT A A x ]A B y Variable Reaction Order rate = A j,s M j,w [M j ]k 0 ″e −E a /RT A A ƒ(T) ƒ(T) = C 1 T/(1 − C 2 T)
[0104] The reaction rate laws are formulated in pseudo-homogeneous form i.e. the heterogeneous (surface) reaction between the aqueous phase and the mineral is multiplied by the factor A j, s M j, w [M j ] to compute a volumetric reaction rate. Any number of kinetic reactions can be specified for a simulation.
[0105] As for kinetically controlled reactions, the appropriate aqueous species and minerals, and corresponding thermodynamic data are automatically selected from the database and presented to the user for review, once the mineralogy and treatment fluids are specified. The user may then accept the default selections, add new species or minerals or modify the default properties. A brief description of the calculation procedure is presented below to assist in adding to or modifying thermodynamic data for aqueous species and minerals.
[0106] Standard partial molal free energy (standard chemical potential) at simulation temperature and pressure, μ i 0 (T, P), is required for each chemical specie that must be added to the equilibrium calculation. The value of μ i 0 (T, P) may be entered directly for each specie, or a model to compute μ i 0 (T, P) must be selected. Table 3 gives a list of available models for computing:
TABLE 3 Models for Calculating Standard Chemical Potential Model Equation Helgeson EOS (for aqueous species) μ i o ( T , P ) = G i , P r , T r o - S i , P r , T r o ( T - T r ) + c i , 1 [ T ln T T r - T + T r ] - c i , 2 { [ ( 1 T - Θ ) - ( 1 T r - Θ ) ] [ Θ - T Θ ] - T Θ 2 ln ( T r ( T - Θ ) T ( T r - Θ ) ) } + a i , 1 ( P - P r ) + a i , 2 ln ( Ψ + P Ψ + P r ) + ( 1 T - Θ ) [ a i , 3 ( P - P r ) + a i , 4 ln ( Ψ + P Ψ + P r ) ] - ω i ( Z + 1 ) + ω i , P r , T r ( Z P r , T r + 1 ) + ω i , P r , T r Y P r , T r ( T - T r ) Helgeson EOS (for minerals) μ i o ( T , P ) = G i , P r , T r o - S i , P r , T r o ( T - T r ) + ∫ T i T ( θ i , 1 + θ i , 2 T + θ i , 3 T - 2 ) T - T ∫ T r T ( θ i , 1 + θ i , 2 T + θ i , 3 T - 2 ) ln T + V P r , T r o ( P - P r ) CpModel (for aqueous species and minerals) C p , i = β i , 0 + β i , 1 T - 0.5 + β i , 2 T 0.5 + β i , 3 T - 1 + β i , 4 T + β i , 5 T - 2 + β i , 6 T 2 + β i , 7 T - 3 C p , i = ( δ H i o δ T ) P , ( δ ( μ i o / T ) δ T ) P = - H i o T 2 Polynomial Model (for aqueous species and minerals) μ i o ( T , P ) = G i , P , T r o + ξ i , 1 T + ξ i , 2 T 2 + ξ i , 3 T 3 + ξ i , 4 T 4 + ξ i , 5 T 5
[0107] Helgeson equation of state (EOS) (in Helgeson, H. C., et al., Summary and Critique of the Thermodynamic Properties of Rock-forming Minerals. American Journal of Science, 1978. 278-A: p. 229 and Tanger, J. C. and H. C. Helgeson, Calculation of the Thermodynamic and Transport Properties of Aqueous Species at High Pressures and Temperatures: Revised Equation of State for the Standard Partial Molal Properties of Ions and Electrolytes. Amer. J. Sci, 1988. 288: p. 19-98.) is the preferred model for both aqueous species and minerals, and majority of data provided with the program is in this form. Chemical species for which data is not available in Helgeson EOS form, the CP model or the polynomial model may be used to estimate μ i 0 (T, P). For chemical species for which data is only available in equilibrium constant form, μ i 0 (T, P) for the specie can be calculated from the following thermodynamic identity
ln ( K ) = - ∑ υ i μ i o RT ,
[0108] provided the values of μ i 0 (T, P) for all the other chemical species in the reaction are known. In a preferred embodiment of the present invention, a graphical tool can be provided to assist in the conversion of equilibrium constant data to free energy form.
[0109] Once μ i 0 (T, P) for aqueous species i is computed at simulation temperature and pressure, the chemical potential of the aqueous species in solution is then computed internally in the simulator from the following equation
μ i ( T, P, {right arrow over (m)} )=μ i 0 ( T, P )+ RTlnγ i ( T, P, {right arrow over (m)} ) m i
[0110] For solvent (water) the following equation is used
μ w ( T, P, {right arrow over (m)} )=μ w 0 ( T, P )+ RTlna w ( T, P, {right arrow over (m)} )
[0111] For minerals that are equilibrated with the aqueous phase species, a separate pure solid phase for that mineral is assumed (i.e. no solid solutions). The equation for the chemical potential for the solid phase specie than simplifies to
μ s ( T, P )=μ s 0 ( T, P )
[0112] The numerical algorithm then computes the value of {right arrow over (m)} for which the system Gibbs free energy is a minimum and the element abundance constraint is satisfied.
[0113] The kinetic and equilibrium models described above compute changes in porosity due to dissolution and precision of minerals. A porosity-permeability relation is then needed to compute the permeability and hence the skin for the treatment. Several porosity-permeability models have been proposed in the literature including the Labrid Model (in Labrid, J. C., Thermodynamic and Kinetic Aspects of Argillaceous Sandstone Acidizing. SPEJ, April 1975: p. 117-128). According to the invention, the following modified Labrid is preferably used:
k k o = ∏ j [ φ 0 + M o , j - M j φ 0 ] δ j
[0114] The modified Labrid model allows each mineral to uniquely impact the permeability, whereas in most other models, permeability changes are completely determined by net changes in porosity without accounting for the identities of the dissolved or precipitated minerals. The parameter δ j in the modified Labrid model is specific to each mineral and allows the mineral identity to impact the permeability. The higher the value of δ j the stronger the impact.
APPLICATION EXAMPLE
[0115] The main features of the invention are illustrated in this section by means of a simple application example. The example is based on core test data reported by Hsi et al (IN Hsi, C. D., S. L. Bryant, and R. D. Neira, SPE 25212 Experimental Validation of Sandstone Acidization Models, in SPE International Symposium on Oilfield Chemistry. 1993. New Orleans) for the Endicott Kediktuk sandstone formation in Alaska. The core tests were conducted on damaged cores at 80° C. with 12/3 Mud acid. The length and diameter of the core plugs were 7.6 and 2.54 cm, respectively. An inductively coupled plasma (ICP) spectrophotometer was used to measure effluent Al and Si concentrations. The HF concentration in the effluent was measured gravimetrically using the weight-loss method with pre-weighted glass slides. The mineralogy of the Kekiktut formation is 98% Quartz and 2% kaolinite.
[0116] [0116]FIG. 1 shows a comparison of the measured effluent concentration of HF, Al, and Si with those predicted by the model of the present invention. The solid lines represent the modeling results, the triangles in FIGS. 1A, 1C and 1 E indicate experimental data for the normalized HF concentration (the normalized HF concentration is the ratio of the HF in the effluent to the injected HF concentration. In FIGS. 1B, 1D and 1 F, the squares represent the Al concentration and the circles the concentration of Si. The tests were performed at 80° C., with 12-3 mud acid, at a flow rate of 0.033 cm/s (FIGS. 1A and 1B), with 12-3 mud acid and a flow rate of 0.0099 cm/s (FIGS. 1C and 1D) and with 6-1.5 mud acid at a flow rate of 0.0099 cm/s (FIGS. 1E and 1F). The model provides a reasonable match to the experimental data even with an order of magnitude change in the flow rate. The match with experimental data was obtained using the default selections of kinetic and thermodynamic data. The match can further be improved by fine tuning the default values.
[0117] On the geochemical model is validated, it can be used to scaleup the results to the reservoir. With the present invention, this requires only a simply switch in the flow geometry from the core to reservoir flow geometry. The pay zone height was assumed to be 3.05 m (10 ft) and the wellbore diameter was assumed to be 0.2032 m (8 in). A preflush volume of 1.24 m 3 /m (100 gal/ft) of 5 wt % HCl was used, followed by a main stage of 2.48 m 3 /m (200 gal/ft) of 12/3 mud acid. The treatment fluids were pumped at 2.65×10 −3 m 3 /sec (1 bbl/min). The graphs in FIG. 2 are a snapshot of the reservoir at the end of the mud acid stage. FIG. 2A shows the mineral profile in the reservoir (in FIG. 2A, the left axis is used for the quartz volume fraction and the right axis for the kaolinite and the colloidal silica). As shown in FIG. 2B, some colloidal silica precipitation did occur, but the amount was not significant enough to impact the permeability appreciably. No AlF 3 or Al(OH) 4 precipitation was observed. FIGS. 2C and 2D show the profile of the dominant aqueous species in the reservoir. HF penetration of about 0.75 m in the formation was achieved at the end of the mud acid stage. FIG. 2D shows the concentration of aluminum fluoride AlF +2 (left axis) and AlF 2 + (right axis) and the concentration of silicon fluoride SiF 6 2− (left axis) and H 2 SiF 6 . This Figure shows that AlF +2 was the dominant aluminum fluoride. Higher fluorides of aluminum than AlF 2 + , such as AlF 3 , AlF 4 − , AlF 5 2− and AlF 6 3− were present in negligible concentrations. SiF 6 2− was the dominant silicon fluoride. Other silicon fluorides were present in negligible concentrations. The aluminum and silicon species Al(OH) 2+ , Al(OH) 2 + , Al(OH) 4 − , H 3 SiO 4 − , H 2 SiO 4 2− and AlO 2 − were also present in negligible concentrations.
[0118] The sensitivity analysis tool facilitates optimization against any of the treatment design parameters. FIGS. 3A and 3B compare the results for the permeability (FIG. 3A) and for the HF concentration (FIG. 3B) for different injection rates and for a different mud acid formulation (9/1 mud acid) against the previous base case examined. The total injection volume was kept constant for all cases shown. At slower injection rates mineral near the sandface are preferentially dissolved, and therefore most of the permeability improvement occurs close to the wellbore. However, at extremely slow injection rates of about 0.1 bbl/min to complete shut-in (not shown), colloidal silica precipitation inhibits permeability improvement. The use of 9/1 mud acid system results in a smaller permeability improvement because the stoichiometric dissolving power of the 9/1 mud acid system is much less than that of the 12/1 mud acid system. Several variations in treatment design parameters may be similarly examined to select the optimum strategy for the final design recommendation.
[0119] In the cases examined herein, the reservoir was considered to be undamaged initially; i.e. the skin before the treatment was zero. FIG. 4 shows the result of the treatment if the reservoir had been damaged with a mineral similar to kaolinite. More precisely, FIG. 4A shows the permeability profile, FIG. 4B the HF concentration profile and FIG. 4C the profile of the differential of pressure between the bottomhole injection pressure P inj and the reservoir pressure at out boundary P res .
[0120] The damage penetration was assumed to be 0.3048 m (1 ft) and the initial skin value was assumed to be 5. All other design parameters were the same as the previous base case. If post-treatment data such as flowback analysis, post-treatment skin and injection pressure data are available, they can be compared against the predictions from the simulator, to assist in diagnosing the type, quantity and depth of damage. The information can be used to optimize future treatments for the reservoir.
[0121] While certain features and embodiments of the invention have been described in detail herein it will be understood that the invention includes all modifications and enhancements within the scope and spirit for the following claims. | A method for designing acid treatments provides for the selection of optimal treatment for well stimulation wherein reservoir characteristics are obtained to further select the reaction kinetic data on the minerals of interests, the treatment to the reservoir is scaled up using a mathematical model and real time damage are computed based on bottomhole pressure and injection rate and compared to that predicted by the mathematical model to adjust the treatment. The model generated facilitates optimization of matrix treatments by providing a rapid quantitative evaluation of various treatment strategies for a formation. Stimulation with non-traditional fluid recipes containing mixtures of inorganic and organic acids, and chelating agents can be readily computed. The computed values can then be used in an economic model to justify the additional costs associated with the use of the non-traditional fluids. Apart from optimizing matrix treatments, the method can be used as a development tool for new fluid systems, as a tool for prediction and removal of inorganic scale and for fluid compatibility testing such as that required in water flooding projects. | 4 |
TECHNICAL BACKGROUND
[0001] The present invention is directed to three-dimensional imaged nonwoven fabrics and the methods for employing such three-dimensional imaged nonwoven fabrics as a means for imparting an improved textured quality or appearance to painted or stained surfaces, or the surface facing materials thereon.
BACKGROUND OF THE INVENTION
[0002] Over the years, the enhancement of the aesthetic qualities of home interiors has been the focus for improvement. In a desire to deviate from flat and perceptually uninteresting wall, ceiling and interior appliance surfaces, artisans have developed and employed a number of techniques by which to modify those surfaces. These techniques address modifying such surfaces by either imparting an actual change in the physical character of the surface, i.e. impart a texture in the actual facing material on the surface, or by creating the perception of depth or irregularity in the paints or stains applied over the surface facing material.
[0003] The modification of the surface facing material to impart an enhanced aesthetic quality involves working with the topical application of plasters, mortars, thin-set cements, or high viscosity polymer based thermosets. As, for example, an interior wall is conventionally fabricated with a sheet-rock outer layer, it is necessary to apply surface facing material to cover or otherwise hide imperfections including nail or screw holes and to provide a homogeneous surface over the extent of the interior wall. During the application of the surface facing material, a modicum of surface texture is sometimes applied by means of stiff bristle over-brushing of the already applied surface facing material or by employing a “stippling” method. The “stippling” method involves subjecting a low viscosity surface facing material to a continuous air stream. The continuous air stream thus disrupts the flow of facing material into droplets or globules, which subsequently disperse as a discontinuous spray of facing material. These droplets or globules impact upon and adhere to the surface being so treated. By the further application of a smooth surface, such as a trowel, with a light level of applied pressure, the droplets or globules are partially spread out on the surface and form what might be considered as a “stippled” surface. While such modifications to the surface facing material generally exhibit an improved aesthetic quality, the nature of the mechanisms is such that a deleterious reproducing pattern is created, a pattern that can detract from the aesthetic quality by naturally drawing the eye to incongruous or faulty areas of the surface. Further, such methods described involve a significant amount of clean-up of the displaced or over-sprayed facing materials.
[0004] Once an interior surface has received a facing material, either in a textured or un-textured form, further application of paints or stains typically follows. As is routinely practiced in the construction of housing and office space interiors, a latex paint is applied by sprayer or roller which results in a homogeneous presentation of color and tint. Significant endeavors have been made to disrupt or alter the homogenous quality in an attempt to enhance the interest of the surface. An example of such a technique is referred to as “faux” or “fauxing”, whereby paints or stains are applied and removed in a random pattern.
[0005] U.S. Pat. No. 5,980,802 to Wakat, et al., U.S. Pat. No. 6,022,588 and U.S. Pat. No. 6,117,494 to Wakat disclose the method whereby a conventional napped or piled paint roller is modified to have an altered surface texture to the roller. When such a roller, either used singly or in plural, is used to apply a paint to a surface, the roller imparts a periodic pattern as the paint roller turns about a central axis. U.S. Pat. No. 5,693,141 to Tramont also discloses an improved paint roller comprising a resilient layer affixed to the paint roller core and an outer layer of loosely folded sheet material attached to the resilient layer. The outer layer employed by Tramont relies upon the loosely folded sheet material having wrinkles which impart the faux textured surface. A general concern exists that the periodicity of the paint roller having a simple surface and turning about the central axis will impart a deleterious reproducing pattern that will again naturally draw the eye to incongruous or faulty areas of the surface.
[0006] An alternate mechanism by which a painted or stained surface can be imparted with a faux texture that attempts to avoid the problems of periodicity experienced by paint roller mechanisms is the method of “ragging” or “blotting”. The art of imparting a faux texture by ragging involves the application of a discontinuous coating of a thinned paint to a surface. The discontinuous coating of paint is created by then blotting the surface with a bundled or bunched “rag”, which is either a linen fabric swatch or wet-laid wood pulp sheet such as a paper towel, and which is preloaded with the thinned paint. As there is only contact with the high points of the bundled or bunched rag, only those points impart paint to the surface. Alternatively, a continuous layer of paint may be initially applied. While the paint is still in a wet state, a clean bundled or bunched rag is blotted against the painted surface and removed. As the rag is withdrawn from the surface, the high points of the fabric or paper towel that have come in contact with the wet paint subsequently removes that paint from the surface. Both fauxing methods are continued in overlapping segments, the amount of pressure applied and the orientation of the rag being varied with each iteration of the paint application or removal process. The end result is an overall surface having localized variations in tint and the perception of depth and texture. While “ragging” can provide a very effective means for altering the aesthetic quality of a surface, optimal results are obtained by the diligent and conscious application of the rag technique so as to avoid repetitive blotting at the same level of pressure and rag orientation. To those artisans particularly familiar with the technique, there remains the problematic nature of the material being used as a rag having a very short useful life-span before the material loses performance, issues of the rag linting or depositing unrestrained fibers into the paint, and the need to vary the practice of the technique else issues of deleterious patterning will occur.
[0007] Direct fauxing techniques have also been employed, as shown in U.S. Pat. No. 5,655,451, to Wasylczuk, et al., whereby a plurality of rigid backed stamps are use in conjunction to create a faux texture. The complexity of orienting each stamp to impart an image yet avoiding repetitive patterning would be extremely taxing on the user and a slow process to the untrained.
[0008] There remains an unmet need for a material that better suits the application of texture to surfaces. In particular, there is a need for a fauxing material that enhances the aesthetic quality of a surface without the complicated procedures of application, does not create undue fouling of the work environment or treated surface, and exhibits an increased working life-span.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to enhancing the aesthetic appearance of surfaces by the contact application of a nonwoven fabric having a three-dimensional image imparted therein. The three-dimensional image of the nonwoven fabric induces a topical modification in either the actual or perceived texture of a surface when the imaged nonwoven fabric is applied to, then removed from the surface. The imaged nonwoven fabric disclosed herein exhibits low Tinting qualities thereby reducing the potential of fiber contamination of the treated surface and is sufficiently durable that the sample can be used and rinsed clean a plurality of times, markedly increasing the working life-span.
[0010] A method of making the present durable nonwoven fabric comprises the steps of providing a precursor web which is subjected to hydroentangling. The precursor web is formed into an imaged nonwoven fabric by hydroentanglement on a three-dimensional image transfer device. The image transfer device typically defines three-dimensional elements against which the precursor web is forced during hydroentangling, whereby the fibrous constituents of the web are imaged by movement into regions between the three-dimensional elements of the transfer device. The image transfer device includes drainage openings each having a downwardly, inwardly tapering configuration. This configuration abates passage of fibers through the openings, and results in formation of a fabric image which corresponds, at least in part, to the pattern of the drainage openings.
[0011] In the preferred form, the precursor web is hydroentangled on a foraminous surface prior to hydroentangling on the image transfer device. This pre-entangling of the precursor web acts to integrate the fibrous components of the web, but does not impart imaging as can be achieved through the use of the three-dimensional image transfer device in subsequent steps.
[0012] It is further contemplated by the present invention that the use of a durable three-dimensional imaged nonwoven fabric can be employed by the layperson with improved results and reduced possibility of deleterious patterning.
[0013] Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The invention will be more easily understood by a detailed explanation of the invention including drawings. Accordingly, drawings which are particularly suited for explaining the invention are attached herewith; however, is should be understood that such drawings are for explanation purposes only and are not necessarily to scale. The drawings are briefly described as follows:
[0015] [0015]FIG. 1 is a diagrammatic view of an apparatus for manufacturing a durable three-dimensional imaged nonwoven fabric, embodying the principles of the present invention;
[0016] [0016]FIG. 2 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “hexagon-Z”;
[0017] [0017]FIG. 3 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “square-Z”;
[0018] [0018]FIG. 4 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “bar-Z”;
[0019] [0019]FIG. 5 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “crisscross-Z”;
[0020] [0020]FIG. 6 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “no hole-Z”;
[0021] [0021]FIG. 7 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “large segmented diamond”;
[0022] [0022]FIG. 8 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “wave”;
[0023] [0023]FIG. 9 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “large basket weave”;
[0024] [0024]FIG. 10 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “large square”;
[0025] [0025]FIG. 11 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “zig-zag”;
[0026] [0026]FIG. 12 is a plan view of a three-dimensional image transfer device of the type used for practicing the present invention, referred to herein as “large honeycomb”;
[0027] [0027]FIG. 13 is a representative depiction of a paint roller body having a three-dimensional image nonwoven fabric;
[0028] [0028]FIG. 14 is a representative depiction of a packaged three-dimensional image nonwoven fabric in a perforated roll form; and
[0029] [0029]FIG. 15 is a representative depiction of a packaged three-dimensional image nonwoven fabric in an interleaved and folded sheet form with dispenser.
DETAILED DESCRIPTION
[0030] While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.
[0031] Nonwoven fabrics are used in a wide variety of applications where the engineered qualities of the fabric can be advantageously employed. These types of fabrics differ from traditional woven or knitted fabrics in that the fabrics are produced directly from a fibrous mat, eliminating the traditional textile manufacturing processes of multi-step yarn preparation, and weaving or knitting. Entanglement of the fibers or filaments of the fabric acts to provide the fabric with a substantial level of integrity. Subsequent to entanglement, fabric integrity can be further enhanced by the application of binder compositions and/or by thermal stabilization of the entangled fibrous matrix.
[0032] U.S. Pat. No. 3,485,706, to Evans, hereby incorporated by reference, discloses processes for effecting hydroentanglement of nonwoven fabrics. More recently, hydroentanglement techniques have been developed which impart images or patterns to the entangled fabric by effecting hydroentanglement on three-dimensional image transfer devices. Such three-dimensional image transfer devices are disclosed in U.S. Pat. No. 5,098,764, hereby incorporated by reference, with the use of such image transfer devices being desirable for providing a fabric with enhanced physical properties as well as having a pleasing appearance.
[0033] For application in fauxing, a nonwoven fabric must exhibit a combination of specific physical characteristics. For example, the nonwoven fabrics used in imparting an actual or perceived texture on a surface should be soft and drapeable so as to conform to the resilient core of a paint roller or can be bunched into a crenellated hand pad, and yet withstand repeated use and rinsings. Further, nonwoven fabrics used in the fauxing of texture must be resistant to abrasion and Tinting yet also exhibit sufficient strength and tear resistance.
[0034] With reference to FIG. 1, therein is illustrated an apparatus for practicing the present method for forming a nonwoven fabric. The fabric is formed from a fibrous matrix preferably comprising staple length fibers, but it is within the purview of the present invention that different types of fibers, or fiber blends, can be employed. The fibrous matrix is preferably carded and air-laid or cross-lapped to form a precursor web, designated P.
[0035] Manufacture of a nonwoven fabric embodying the principles of the present invention is initiated by providing the precursor nonwoven web preferably in the form of a blend of staple length fibers. Such fibers may be selected from fibers of natural or synthetic composition and, of homogeneous or mixed fiber length. Suitable natural fibers include, but are not limited to, cotton, wood pulp and viscose rayon. Synthetic fibers which may be blended in whole or part include thermoplastic and thermoset polymers. Thermoplastic polymers suitable for this application include polyolefins, polyamides and polyesters. The thermoplastics may be further selected from homopolymers, copolymers, conjugates and other derivatives including those thermoplastic polymers having incorporated melt additives or surface modification agents, either of which may be selected from the group consisting of hydrophobic modifiers and hydrophilic modifiers. Staple lengths are selected in the range of 0.25 inch to 4 inches, the range of 1 to 2 inches being preferred and the fiber denier selected in the range of 0.08 to 15, the range of 1 to 6 denier being preferred for general applications. The profile of the fiber is not a limitation to the applicability of the present invention.
[0036] The composition of the three-dimensional imaged nonwoven fabric can be specifically chosen in light of the paint, stain, or surface facing material to be used or applied. For example, if a water based latex paint is to be applied, a hydrophobic thermoplastic polymer fiber such as polypropylene staple fiber, or a hydrophobic melt additive in a polyester staple fiber, would facilitate the imaged nonwoven fabric not overly absorbing the paint. Should it be known that an abrasive surface facing material, such as a plaster, is to be textured, a polyamide staple fiber selected from the upper range of staple fibers would be advised.
[0037] It is within the purview of the present invention that a scrim can be interposed in the formation of the precursor nonwoven web. The purpose of the scrim is to reduce the extensibility of the resultant three-dimensional imaged nonwoven fabric, thus reducing the possibility of three-dimensional image distortion and further enhancing fabric durability. Suitable scrims include unidirectional monofilament, bi-directional monofilament, expanded films, and thermoplastic spunbond.
[0038] It is also within the purview of the present invention that a binder material can be incorporated either as a fusible fiber in the formation of the precursor nonwoven web or as a liquid fiber adhesive applied after imaged fabric formation. The binder material will further improve the durability of the resultant imaged nonwoven fabric during application of harsh or abrasive surface treatments.
[0039] [0039]FIG. 1 depicts the means for imparting the three-dimensional quality during the manufacture of the nonwoven fabric. The image transfer device shown as imaging drum 18 can be selected from a broad variety of three-dimensional image types. Exemplary FIGS. 2, 3, 4 , 5 and 6 , are three-dimensional images of the “nub” type. Fibrous nubs are formed during the process of entangling on the imaging drum 18 , these nubs extending out of the planar background of the resulting fabric. These fibrous nubs act as the high points described in the “ragging” technique. These nubs are typically formed where fibers of the precursor web are directed generally into drainage openings in the surface of the imaging device as high pressure liquid is directed against the precursor web. In these illustrations, the drainage openings are shown as white against the gray background, with upstanding three-dimensional elements (when provided) shown in black. The image transfer devices illustrated in these drawings form fabric “nubs” corresponding to the thickness (0.15″) at the drainage openings. To abate fiber passage through the drainage openings, the openings are formed in an inwardly tapering configuration.
[0040] [0040]FIGS. 7, 10, 11 , and 12 , are examples of the “geodesic” type of images. In this image type, regular blocks of entangled constituent fibers extended out of the planar background, the fibrous blocks creating high points that are particularly effective at disrupting deleterious patterning when applied in the ragging technique. These high points are formed about the upstanding three-dimensional surface elements of the imaging surface against the foraminous planar background of the surface. These surface elements are illustrated in black, and had a dimension of 0.10″ projecting above the planar background of the surface.
[0041] [0041]FIGS. 8 and 9 represent images of the “natural” type. In FIG. 8, upstanding “walls” extend upwardly from the forming surface, with drainage openings extending downwardly therefrom. In FIG. 9, surface elements (black) extend across a foraminous background surface of the image transfer device. The flexibility inherent to the fabrication of the image on the image transfer device, variations in three-dimensional image including multi-planar images, variations in image juxtaposition, and the ability to create complex images having no discontinuities allow for the creation of textures in textiles not seen in the art. Apertures or holes can also be created in the nonwoven fabric. Such apertures can allow for air transfer between layers when bunched in a rag, which prevents tacking of the fabric layers, and can allow for the presentation of subsurface resilient layers when employed as a paint roller cover.
[0042] Three-dimensional imaged nonwoven fabrics designed for enhancing the aesthetic qualities of surfaces can ultimately be employed by a number of different mechanisms. U.S. Pat. No. 5,397,414 to Garcia, et al., and U.S. Pat. No. 4,467,509 to Dezen, hereby incorporated by reference, disclose mechanisms by which the nonwoven fabric may be fabricated in paint roller body. The general design is such that a strip of imaged nonwoven fabric is wrapped about a cylindrical tube of 4 to 12 inches in length as depicted in FIG. 13. The paint roller includes an inner resilient cylindrical core, and an outer annular surface contact material formed in accordance with the present invention. The outer material forms a paint roll medium that is fixedly attached to the resilient core. The resilient core and paint roll medium rotate together about an axis of the cylindrical core during use. The outer material can be loosely attached to the resilient core so as to form irregular pleats. Most usually, the nonwoven fabric is wrapped at an angled juxtaposition such that a transverse seam along the long axis of the cylinder is avoided. In the alternative, sheets of imaged nonwoven fabric are packaged such that a single sheet is made available to the user at any point in time. Examples of such packaging include continuous rolls of nonwoven fabric of a minimum 10 to 12″ width and of convenient finite length. Imaged nonwoven fabric packed in a roll 30 as shown in FIG. 14, would further have evident pre-formed perforations 31 at a recurrent distance of separation throughout the length of the roll 30 , these perforations facilitating the removal of a single sheet 32 by tearing across the width at these locations. Single sheets 42 of imaged nonwoven fabric can also be supplied as individual sheets having been stacked in a multifold orientation as shown in FIG. 15. Thusly packaged, as a single sheet is removed, a subsequent sheet is partially extended out of the box 40 through slot 41 , and made ready for removal.
[0043] The imaged nonwoven fabric is further designed to facilitate optimal performance when used by the non-artisan. Of primary concern when employing a ragging or fauxing technique is to avoid the creation of re-occurring patterns. The presence of patterns is naturally and immediately visible to the human eye and any subtle variation in that pattern will result in a detracting and particularly strong “artificial” feel. When the desire is to impart an interesting aesthetic quality on a surface such as an interior wall by fauxing, patterning should be avoided. The inherent three-dimensional image in the nonwoven fabric of the present invention aids in the fauxing technique by breaking or disrupting potential pattern creation.
EXAMPLES
Example 1
[0044] Using a forming apparatus of the type illustrated in FIG. 1, a nonwoven fabric was made in accordance with the present invention by providing a precursor web comprising 100 percent by weight polyester fibers as supplied by Wellman as Type T-472 PET, 1.2 dpf by 1.5 inch staple length. The precursor fibrous batt was entangled by a series of entangling manifolds such as diagrammatically illustrated in FIG. 1. FIG. 1 illustrates a hydroentangling apparatus for forming nonwoven fabrics in accordance with the present invention. The apparatus includes a foraminous forming surface in the form of belt 12 upon which the precursor fibrous batt P is positioned for pre-entangling by entangling manifold 14 . In the present examples, the entangling manifold 14 included three orifice strips each including 120 micron orifices spaced at 42.3 per inch, with the orifice strips of the manifold successively operated at 100, 300, and 600 pounds per square inch, and with a line speed of 45 feet per minute. The precursor web was then dried using two stacks of steam drying cans at 300° F. The precursor web had a basis weight of 1.5 ounce per square yard (plus or minus 7%).
[0045] The precursor web then received a further 2.0 ounce per square yard air-laid layer of Type-472 PET fibrous batt. The precursor web with fibrous batt was further entangled by a series of orifice strips as described above, with the orifice strips successively operated at 100, 300, and 600 pounds per square inch, with a line speed of 45 feet per minute. The exemplary entangling apparatus of FIG. 1 further includes an imaging drum 18 comprising a three-dimensional image transfer device for effecting imaging of the now-entangled layered precursor web. The image transfer device includes a moveable imaging surface which moves relative to a plurality of entangling manifolds 22 which act in cooperation with three-dimensional elements defined by the imaging surface of the image transfer device to effect imaging and patterning of the fabric being formed. The entangling manifolds 22 included 120 micron orifices spaced at 42.3 per inch, with the manifolds operated at 2800 pounds per square inch each. The imaged nonwoven fabric was dried using two stacks of steam drying cans at 300° F.
[0046] The three-dimensional image transfer device of drum 18 was configured with a multiple image forming surface consisting of five different patterns, as illustrated in FIGS. 2, 3, 4 , 5 , and 6 .
Example 2
[0047] An imaged nonwoven fabric was fabricated by the method specified in Example 1, where in the alternative, the precursor fibrous batt was comprised of viscose rayon as supplied by Lenzing at T-8191, 1.5 dpf by 1.5 inch staple length. Final weight of the dried prebond layer before layering of the PET fiber fibrous batt was 1.5 ounces per square yard.
Example 3
[0048] An imaged nonwoven fabric was fabricated by the method specified in Example 1, where in the alternative, the precursor fibrous batt was comprised of 2.0 ounces per square yard PET fiber.
Example 4
[0049] An imaged nonwoven fabric was fabricated by the method specified in Example 2, where in the alternative, the precursor fibrous batt was comprised of 2.0 ounces per square yard viscose rayon.
Fabric Strength/Elongation ASTM D5034 Elmendorf Tear ASTM D5734 Handle-o-meter ASTM D2923 Stiffness - Cantilever Bend ASTM D5732 Fabric Weight ASTM D3776
[0050] The test data in Table 1 shows that nonwoven fabrics approaching, meeting, or exceeding the various above-described benchmarks for fabric performance in general, and to commercially available products in specific, can be achieved with fabrics formed in accordance with the present invention. Fabrics having basis weights between about 2.0 ounces per square yard and 6.0 ounces per square yard are preferred, with fabrics having basis weights of about 3.0 ounces per square yard and 4.0 ounces per square yard being most preferred. Fabrics formed in accordance with the present invention are durable and drapeable, which is suitable for faux texturing applications.
[0051] From the foregoing, it will be observed that numerous modifications and variations can be affected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.
Combined Combined Three- Grab Grab Grab Grab Canti- Canti- Tensile Elongation Fiber Dimen- Ten- Ten- Elonga- Elonga- Soft- Soft- lever lever Elmendorf Elmendorf Per Per Compo- sional Basis sile sile tion tion ness ness Bend Bend Tear Tear Basis Basis sition Image Weight Bulk (MD) (CD) (MD) (CD) (MD) (CD) (MD) (CD) (MD) (CD) Weight Weight EXAM- FIG- 3.5 0.096 43.2 65.8 27.0 141.9 98 47 8.8 5.3 2348.0 3983.6 31.5 48.8 PLE 1 URE 2 FIG- 3.4 0.092 45.8 62.8 28.9 149.0 77 48 7.6 5.3 2641.4 No Tear 31.8 52.0 URE 3 FIG- 3.3 0.088 43.0 63.5 25.0 142.4 93 46 7.6 5.2 2412.3 4439.4 32.2 50.6 URE 4 FIG- 3.3 0.092 37.7 66.7 25.6 161.2 82 42 8.7 5.2 2536.0 No Tear 31.7 56.8 URE 5 FIG- 3.8 0.092 68.0 46.7 42.7 109.7 85 35 8.2 5.3 1458.7 3751.1 30.0 39.9 URE 6 EXAM- FIG- 3.9 0.063 35.5 53.1 27.0 149.8 106 32 9.0 6.1 1785.7 3704.8 22.7 45.3 PLE 2 URE 2 FIG- 4.0 0.075 30.9 58.2 24.3 152.0 91 25 7.5 4.6 1877.6 3933.4 22.6 44.6 URE 5 FIG- 3.8 0.071 34.5 58.4 26.3 146.6 99 35 8.2 6.4 1576.7 4129.0 24.4 45.5 URE 8 FIG- 3.8 0.070 30.8 53.7 24.7 151.4 101 20 8.1 5.0 1745.4 3454.0 22.1 46.1 URE 11 FIG- 4.1 0.074 44.4 40.3 32.0 108.2 98 23 8.4 5.6 1129.8 3085.6 20.4 33.8 URE 14 EXAM- FIG- 3.8 0.105 43.2 70.8 28.1 135.6 112 54 9.0 6.2 2618.3 4185.2 30.2 43.3 PLE 4 URE 2 FIG- 3.7 0.092 44.5 73.7 28.7 147.8 84 46 8.0 6.2 2892.6 4784.1 31.9 47.7 URE 5 FIG- 3.7 0.088 44.3 71.1 29.8 167.4 105 60 8.4 5.9 2872.3 4716.7 31.2 53.3 URE 8 FIG- 3.6 0.092 42.2 70.8 25.9 137.6 100 51 8.9 6.1 2558.3 4088.8 31.6 45.7 URE 11 FIG- 4.3 0.093 75.6 53.0 45.7 111.8 114 48 9.0 5.7 1547.8 4157.8 29.9 36.6 URE 14 EXAM- FIG- 4.3 0.074 32.2 45.1 26.8 138.0 131 49 8.5 6.6 2156.9 4057.9 18.0 38.3 PLE 5 URE 2 FIG- 4.3 0.082 26.4 36.8 20.8 138.2 124 38 7.8 5.3 2437.9 4159.9 14.7 37.0 URE 5 FIG- 4.3 0.082 26.4 36.8 20.8 138.3 124 38 7.8 5.3 2437.9 4159.6 14.7 37.0 URE 8 FIG- 4.2 0.086 30.5 54.4 17.7 110.8 132 46 7.1 4.8 2687.8 3558.1 20.1 30.4 URE 11 FIG- 4.5 0.083 46.1 41.9 34.4 98.0 127 34 8.8 5.6 1441.0 2966.4 19.6 29.4 URE 14 | The present invention is directed to enhancing the aesthetic appearance of surfaces by the contact application of a nonwoven fabric having a three-dimensional image imparted therein. The three-dimensional image of the nonwoven fabric induces a topical modification in either the actual or perceived texture of a surface when the imaged nonwoven fabric is applied to, then removed from, the surface. The imaged nonwoven fabric disclosed herein exhibits low Tinting qualities thereby reducing the potential of fiber contamination of the treated surface and is sufficiently durable that the sample can be used and rinsed clean a plurality of times, markedly increasing the working life-span. | 3 |
BACKGROUND OF THE INVENTION
This relates to N-well or P-well strap structures for use in integrated circuits.
N-well or P-well strap structures are typically used in integrated circuits to tie a source line to a well region so as to assure that the voltage in the well region is the same as the voltage at the source line.
FIGS. 1 and 2 depict a top view and a cross-section along lines 2 - 2 of FIG. 1 of a typical integrated circuit structure 100 that includes an active device and a well strap formed in a well in a semiconductor substrate 105 It will be understood that this structure may be replicated multiple times in the integrated circuit. Structure 100 includes source and drain regions 110 , 120 formed in a well 130 with a polysilicon gate finger 140 formed on a dielectric layer (not shown) on the surface of well 130 . These elements will be recognized as forming a MOS transistor; but it is to be understood that the MOS transistor is only illustrative of any active device. Following industry practice, the length L of gate 140 is its shorter dimension.
Structure 100 further includes diffusion region 160 that makes ohmic contact with well 130 and ohmic contacts (or taps) 115 to source region 110 , ohmic contacts 125 to drain region 120 , and ohmic contacts 165 to diffusion region 160 . The diffusion region 160 and its contacts or taps 165 constitute the well strap. A shallow trench isolation (STI) region 150 surrounds the active device and well strap.
Illustratively, the transistor is a PMOS transistor, source and drain regions are P-type, well 130 is an N-type well, and diffusion region 160 is N-type. Alternatively, the transistor is an NMOS transistor, source and drain regions 110 , 120 are N-type, and well 130 and diffusion region 160 are P-type.
In certain prior art integrated circuits, the N-well or P-well strap is placed so that it is directly abutting an active device such as the MOS transistor as shown in FIGS. 1 and 2 . Further details concerning such an implementation of a N-well strap may be found in U.S. Pat. No. 7,586,147B2 for “Butted Source Contact and Well Strap,” which is incorporated herein by reference. In alternative structures, the well strap may form a ring around the active device or group of active devices.
In certain other prior art integrated circuits, dummy polysilicon is placed next to the device gates so as to control uniformity of critical dimensions. In this case, the well strap is spaced apart from the active device. FIG. 3 is a top view of such a prior art integrated circuit structure 300 including an active device and a well strap. Illustratively, structure 300 includes source and drain regions 310 , 320 formed in a well 330 with a polysilicon gate finger 340 formed on a dielectric layer (not shown) on the surface of well 330 . These elements will be recognized as forming a MOS transistor; but it is to be understood that the MOS transistor is only illustrative of any active device. A substrate (not shown) similar to substrate 105 of FIG. 2 underlies well 330 .
Structure 300 further includes diffusion region 360 that makes ohmic contact with well 330 and ohmic contacts (or taps) 315 to source region 310 , ohmic contacts 325 to drain region 320 , and ohmic contacts 365 to diffusion region 360 . The diffusion region 360 and its contacts or taps 365 constitute the well strap. A STI region 350 surrounds the active device and the well strap. Again, the transistor can be a PMOS transistor with P-type source and drain regions 310 , 320 and N-type well 330 and diffusion region 360 ; or the transistor can be a NMOS transistor with N-type source and drain regions 310 , 320 and P-type well 330 and diffusion region 360 .
Structure 300 further comprises dummy polysilicon gate fingers 371 , 372 located on opposite sides of the active device above portions of the STI region 350 . As a result, the well strap is separated from the active device by at least one length of the dummy polysilicon finger.
In certain other prior art integrated circuits, double dummy polysilicon is placed next to active devices. FIG. 4 is a top view of such a prior art integrated circuit structure 400 including an active device and a well strap. Illustratively, structure 400 includes on the left-hand side source and drain regions 410 , 420 formed in a well 430 with a polysilicon gate finger 440 formed on a dielectric layer (not shown) on the surface of well 430 . These elements will be recognized as forming a first MOS transistor; but it will be understood that the MOS transistor is only illustrative of any active device. A second MOS transistor is formed on the right-hand side of FIG. 4 and includes the same elements bearing the same numbers followed by the suffix A. Again, a substrate (not shown) similar to substrate 105 of FIG. 2 underlies well 430 .
Structure 400 further includes diffusion region 460 that makes ohmic contact with well 430 and ohmic contacts (or taps) 415 to source region 410 , ohmic contacts 425 to drain region 420 , and ohmic contacts 465 to diffusion region 460 . The diffusion region 460 and its contacts or taps 465 constitute the well strap. A STI region 450 surrounds the active devices and the well strap. Again, the transistor can be a PMOS transistor with P-type source and drain regions 410 , 420 and N-type well 430 and diffusion region 460 ; or the transistor can be a NMOS transistor with N-type source and drain regions 410 , 420 and P-type well 430 and diffusion region 460 .
Structure 400 further comprises dummy polysilicon gate fingers 471 , 472 , 473 , 474 with the first two fingers 471 , 472 located above portions of STI region 450 between the well strap and the first transistor and the second two fingers 473 , 474 being located above other portions of STI regions 450 between the well strap and the second transistor. As a result, the well strap is separated from the active device by at least two lengths of the dummy polysilicon fingers.
SUMMARY OF THE INVENTION
The use of increasing numbers of dummy polysilicon gate fingers to separate the active device(s) from the well strap takes up considerable amount of space on the semiconductor substrate. The present invention is improved N-well or P-well strap structures with lower space requirements. In illustrative embodiments, reduced space requirements are achieved by forming the strap on both sides of one or more floating polysilicon gate fingers.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the present invention will be apparent to those of ordinary skill in the art in view of the following Detailed Description in which:
FIGS. 1 and 2 are a top view and a cross-sectional view of a first well strap structure of the prior art;
FIG. 3 is a top view of a second prior art well strap structure;
FIG. 4 is a top view of a third prior art well strap structure;
FIGS. 5 and 6 are a top view and a cross-sectional view of a first illustrative embodiment of the invention;
FIG. 7 is a top view of a second illustrative embodiment of the invention;
FIG. 8 is a top view of a third illustrative embodiment of the invention; and
FIG. 9 is a top view of a fourth illustrative embodiment of the invention.
DETAILED DESCRIPTION
FIGS. 5 and 6 are a top view and a cross-sectional view of a first illustrative embodiment of the invention. Structure 500 includes source and drain regions 510 , 520 formed in a well 530 with a polysilicon gate finger 540 formed on a dielectric layer (not shown) on the surface of well 530 . These elements will be recognized as forming a MOS transistor; but it will be understood that the MOS transistor is only illustrative of any active device that may be used in the practice of the invention. A second MOS transistor is formed on the right-hand side of FIG. 5 and includes the same elements bearing the same numbers followed by the suffix A. As shown in FIG. 6 , a semiconductor substrate 605 underlies well 530 .
Structure 500 further includes diffusion regions 560 , 562 that make ohmic contact with well 530 , a floating polysilicon gate finger 580 between diffusion regions 560 , 562 , and ohmic contacts (or taps) 515 to source region 510 , ohmic contacts 525 to drain region 520 , and ohmic contacts 565 , 567 to diffusion regions 560 , 562 . The diffusion regions 560 , 562 , and contacts or taps 565 , 567 constitute the well strap. A STI region 550 surrounds the active devices and the well strap. As shown in FIG. 5 , taps 565 and taps 567 are on opposite sides of floating gate finger 580 . While two taps 565 and two taps 567 are shown, a single tap 565 or 567 or more than two taps 565 or 567 may be used.
Structure 500 further comprises dummy polysilicon gate fingers 575 , 576 located on opposite sides of diffusion regions 560 , 562 and above portions of STI region 550 . As a result, the well strap is separated from the active device by only one length of the dummy polysilicon gate finger, thereby reducing the distance between the active device and the diffusion region 560 compared with the distance between the active device and the diffusion region 460 in the prior art structure of FIG. 4 .
To form structure 500 , dopants of a first conductivity-type, illustratively N-type, are first implanted in a substrate 602 of a second conductivity type, illustratively P-type, to form an N-type well 530 . STI region 550 is then formed in well 530 . An insulating layer is then formed on the surface of the well; and polysilicon gate fingers 540 , 540 A, 575 , 576 , 580 are formed on the insulating layer. Lightly doped drain regions are then formed in the well on each side of gates 540 , 540 A; and sidewalls 542 , 542 A are then formed on the sides of gates 540 , 540 A. The gates and sidewalls are then used as masks to control the implantation of dopants during formation of the source and drain regions and the diffusion regions. Illustratively P-type dopants are implanted on both sides of gates 540 , 540 A and sidewalls 542 , 542 A to form source regions 510 , 510 A and drain regions 520 , 520 A of the PMOS transistors; and N-type dopants are implanted on both sides of gate finger 580 to form diffusion regions 560 , 562 . Because the gates and sidewalls shield the well regions directly underneath them, these well regions are not doped during the implantation process with the result that separate source and drain regions and separate diffusion regions 560 , 562 are formed. Holes are then made in the insulating layer and contacts are formed to the source and drain regions 510 , 510 A, 520 , 520 A and the diffusion regions 560 , 562 . Advantageously, the N-type diffusion regions 560 , 562 may be formed at the same time as the same process is used to form other N-type regions, such as source and drain regions, elsewhere on the integrated circuit; and similarly, the P-type process used to form the P-type source and drain regions 510 , 510 A, 520 , 520 A may be used to form P-type diffusion regions elsewhere on the integrated circuit.
FIG. 7 is a top view of a second illustrative embodiment of the invention. Structure 700 includes source and drain regions 710 , 720 formed in a well (not shown) with a polysilicon gate finger 740 formed on a dielectric layer (not shown) on the surface of the well. These elements will be recognized as forming a MOS transistor; but it will be understood that the MOS transistor is only illustrative of any active device that may be used in the practice of the invention. A second MOS transistor is formed on the right-hand side of FIG. 7 and includes the same elements bearing the same numbers followed by the suffix A. The well is formed in a semiconductor substrate (not shown); and the cross-section of the active device, well and substrate of the embodiment of FIG. 7 is similar to the cross-section of the active device, well 630 and substrate 605 of FIG. 6 .
Structure 700 further includes diffusion regions 760 , 762 , 764 that make ohmic contact with well 730 , at least two floating polysilicon gate fingers 782 , 784 between diffusion regions 760 , 762 and ohmic contacts (or taps) 715 to source region 710 , ohmic contacts 725 to drain region 720 , and ohmic contacts 765 , 767 to diffusion regions 760 , 762 . No contacts are made to diffusion region 764 with the result that region 764 is left floating. The diffusion regions 760 , 762 , and contacts or taps 765 , 767 constitute the well strap. A STI region 750 surrounds the active devices and the well strap. As shown in FIG. 7 , taps 765 and taps 767 are on opposite sides of floating gate fingers 782 , 784 .
Structure 700 further comprises dummy polysilicon gate fingers 775 , 777 located on opposite sides of the active device and above portions of the STI region 750 . As a result, the well strap is separated from the active device by only one length of the dummy polysilicon gate finger, thereby reducing the distance between the active device and the diffusion region compared to prior art structures.
The process for forming structure 700 and the resulting structural cross-section are substantially the same as those of structure 500 except that two floating polysilicon gate fingers 782 , 784 are used instead of a single polysilicon gate finger 580 with the result that three diffusion regions 760 , 762 , 764 are formed instead of two.
FIG. 8 is a top view of a third illustrative embodiment of the invention. Structure 800 includes source and drain regions 810 , 820 formed in a well (not shown) with a polysilicon gate finger 840 formed on a dielectric layer (not shown) on the surface of the well. These elements will be recognized as forming a MOS transistor; but it will be understood that the transistor is only illustrative of any active device that may be used in the practice of the invention. A second MOS transistor is formed on the right-hand side of FIG. 8 and includes the same elements bearing the same numbers followed by the suffix A. Again, the well is formed in a semiconductor substrate (not shown); and the cross-section of the active device, well and substrate of the embodiment of FIG. 8 is similar to the cross-section of the active device, well 630 and substrate 605 of FIG. 6 .
Structure 800 further includes diffusion regions 860 , 862 that make ohmic contact with well 830 , a floating polysilicon gate finger 880 between diffusion regions 860 , 862 and ohmic contacts (or taps) 815 to source region 810 , ohmic contacts 825 to drain region 820 , and ohmic contacts 865 to diffusion region 860 . As shown in FIG. 8 , the contacts 865 to diffusion region are located on only one side of the floating polysilicon gate finger 880 with the result that diffusion region 862 is left floating. The diffusion region 860 and contacts or taps 865 constitute the well strap. A STI region 850 surrounds the active devices and the diffusion regions.
Structure 800 further comprises dummy polysilicon gate fingers 871 , 872 located on opposite sides of the active device and above the diffusion regions. As a result, the well strap is separated from the active device by only one length of the dummy polysilicon gate finger; and the size of diffusion region 862 is reduced by eliminating the taps on one side of the floating gate finger.
The process for forming structure 800 and the resulting structural cross-section are substantially the same as those of structure 500 except that contacts to the diffusion region are formed on only one side of the floating polysilicon gate finger 880 .
FIG. 9 is a top view of a fourth illustrative embodiment of the invention. Structure 900 includes source and drain regions 910 , 920 formed in a well (not shown) with a polysilicon gate finger 940 formed on a dielectric layer (not shown) on the surface of the well. These elements will be recognized as forming a MOS transistor; but it will be understood that the MOS transistor is only illustrative of any active device that may be used in the practice of the invention. A second MOS transistor is formed on the right-hand side of FIG. 9 and includes the same elements bearing the same numbers followed by the suffix A. Again, the well is formed in a semiconductor substrate (not shown); and the cross-section of the active device, well and substrate of the embodiment of FIG. 9 is similar to the cross-section of the active device, well 630 and substrate 605 of FIG. 6 .
Structure 900 further includes diffusion regions 960 , 962 , 964 that make ohmic contact with well 930 , at least two floating polysilicon gate fingers 982 , 984 between diffusion regions 960 , 962 , 964 , and ohmic contacts (or taps) 915 to source region 910 , ohmic contacts 925 to drain region 920 , and ohmic contacts 965 to diffusion region 960 . As shown in FIG. 9 , the contacts 965 to diffusion region 960 are located on only one side of the floating polysilicon gate fingers 982 , 984 with the result that diffusion regions 962 , 964 are left floating. The diffusion region 960 and contacts or taps 965 constitute the well strap. A STI region 950 surrounds the active devices and the well strap.
Structure 900 further comprises dummy polysilicon gate fingers 971 , 972 located on opposite sides of the active device and above portions of the STI regions. As a result, the well strap is separated from the active device by only one length of the dummy polysilicon gate finger; and the size of the diffusion region is reduced by eliminating the contacts on one side.
The process for forming structure 900 and the resulting structural cross-section are substantially the same as those of structure 700 except that contacts to the diffusion region are made on only one side of the floating polysilicon gate fingers 982 , 984 .
As will be apparent to those skilled in the art, numerous variations may be practiced within the spirit and scope of the present invention. For example, the well and diffusion region can be either a P-type well and diffusion region or an N-type well and diffusion region. If the active device is a transistor, it can be an NMOS transistor in a P-well or a PMOS transistor in an N-well. Other active devices may also be used in the practice of the invention. For purposes of illustration, the contacts or taps have been depicted as a pair of contacts; but the invention may be practiced with a single contact or with more than two contacts. Other modifications will be apparent to those skilled in the art. | Embodiments of N-well or P-well strap structures are disclosed with lower requirements achieved by forming the strap on both sides of one or more floating polysilicon gate fingers. | 7 |
FIELD OF THE INVENTION
[0001] The invention relates to the design and fabrication of a magnetic tunnel junction (MTJ) Magnetic Random Access Memory (MRAM) array, and more specifically to magnetic tunnel junction devices with improved signal-to-noise ratio and switching behavior.
BACKGROUND OF THE INVENTION
[0002] The magnetic tunnel junction (MTJ) basically comprises two electrodes, which are layers of ferromagnetic material, separated by a tunnel barrier layer, which is a thin layer of insulating material. The tunnel barrier layer must be sufficiently thin so that there is a probability for charge carriers (typically electrons) to cross the layer by means of quantum mechanical tunneling. The tunneling probability is spin dependent, however, depending on the availability of tunneling states with different electron spin orientations. Thus, the overall tunneling current will depend on the number of spin-up vs. spin-down electrons, which in turn depends on the orientation of the electron spin relative to the magnetization direction of the ferromagnetic layers. Thus, if these magnetization directions are varied for a given applied voltage, the tunneling current will also vary as a function of the relative directions. As a result of the behavior of an MTJ, sensing the change of tunneling current for a fixed potential can enable a determination of the relative magnetization directions of the two ferromagnetic layers that comprise it. Equivalently, the resistance of the MTJ can be measured, since different relative. magnetization directions will produce different resistances.
[0003] The use of an MTJ as an information storage device requires that the magnetization of at least one of its ferromagnetic layers can be varied relative to the other and also that changes in the relative directions can be sensed by means of variations in the tunneling current or, equivalently, the junction resistance. In its simplest form as a two state memory storage device, the MTJ need only be capable of having its magnetizations put into parallel (low resistance) or antiparallel (high resistance) configurations (writing data) and that these two configurations can be sensed by tunneling current variations or resistance variations (reading data). In practice, the free ferromagnetic layer can be modeled as having a magnetization which is free to rotate but which energetically prefers to align in either direction along its easy axis (the direction of magnetic crystalline anisotropy). The magnetization of the fixed layer may be thought of as being permanently aligned in its easy axis direction. When the free layer is anti-aligned with the fixed layer, the junction will have its maximum resistance, when the free layer is aligned with the fixed layer, the minimum resistance is present.
[0004] In typical MRAM circuitry, the MTJ devices are located at the intersection of current carrying lines called word lines and bit lines. When both lines are simultaneously activated, information gets written on the device, i.e. the magnetization direction of its free layer is changed. When only one line is activated, the resistance of the device can be sensed, so the device is effectively read.
[0005] A routine search of the prior art was performed with the following references of interest being found:
[0006] U.S. Pat. No. 5,650,958 (Gallagher et al) discloses a barrier layer between free and pinned layers while U.S. Pat. No. 6,166,948 (Parkin et al) shows a multi-layer free layer structure and U.S. Pat. No. 6,665,155 (Gill) describes an amorphous cobalt niobium or cobalt hafnium layer between two free layers.
[0007] In U.S. Pat. No. 5,966,012 (Parkin),U.S. Pat. No. 6,839,206 (Saito et al), and U.S. Pat. No. 6,756,237 (Xiao et al) use of an amorphous barrier layer is disclosed and, in U.S. Pat. No. 6,831,312, Slaughter et al. teach at least one amorphous layer for smoothness so that the free layer and the ferromagnetic layers, for example, may comprise amorphous alloys of CoFeB.
[0008] U.S. Pat. No. 6,818,458 (Gill) shows an amorphous alloy of CoFeX as a ferromagnetic layer for smooth growth of a thin barrier layer while U.S. Pat. No. 6,452,762 (Hayashi et al) teaches that the fixed layer and the free layer may be of amorphous material. In U.S. Pat. No. 6,703,654 (a Headway patent by Horng et al) a smooth bottom electrode is disclosed. Finally, U.S. Patent Publication 2004/0229430 (Findeis et al) describes a free layer comprising multiple layers including amorphous CoFeB alloys.
[0009] Because of their greater dR/R and very low Hc, MTJ devices with amorphous CoFeB free layers are preferred for ultra high density and low power MRAM applications. In practice, however, the extremely high positive magnetostriction of CoFeB is a source of problems such as a widely varying switching field distribution among MRAM arrays. The present invention discloses how these problems can be overcome through suitable control of the composition and structure of free layer films.
SUMMARY OF THE INVENTION
[0010] It has been an object of at least one embodiment of the present invention to provide a TMR based device having improved sensitivity.
[0011] Another object of at least one embodiment of the present invention has been that said device have increased breakdown and reduced current characteristics.
[0012] Still another object of at least one embodiment of the present invention has been that said device have minimal magnetostrictive behavior.
[0013] A further object of at least one embodiment of the present invention has been to provide a process for manufacturing said device.
[0014] These objects have been achieved by arranging for the ferromagnetic layers of the device to have an amorphous structure, particularly those films that contact the dielectric layer. An amorphous film is smoother than a film with crystalline structure since it has no preferred texture. To ensure the dissipation of any epitaxial effects that derive from the layer on which each of these amorphous layers is deposited, they are required to have a minimum thickness (of about 15 Å). A preferred material for contacting the dielectric layer is CoFeB. This has an amorphous structure when certain constituents exceed a particular concentration. CoFeB does, however, have an undesirably large magnetostriction constant. Ways of overcoming this latter problem are disclosed and a description of a process for manufacturing the device is included.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic illustration of the structure of the invention
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0016] It is known that the smoothness of TMR films, especially, the dielectric layer, is critical to achieving high dr/r and other vital parameters such as breakdown voltage(Vbd), the dropping rate of TMR versus applying voltage, and V 50 (voltage at which dR/R is reduced by 50%). Thus improved techniques are needed to obtain a smooth film prior to depositing the dielectric layer.
[0017] The structure of the invention is schematically illustrated in FIG. 1 . Seen there are upper and lower conductive leads 18 and 19 with seed layer 10 being on layer 19 . Antiferromagnetic layer 11 lies on seed layer 10 while AP2 and AP1 layers, 12 and 14 respectively, are immediately above it, with AFM decoupling layer 13 between them. Dielectric tunneling layer 15 lies on AP1 layer 14 and free layer 16 is on top of layer 15 . Capping layer 17 , on free layer 16 , completes the structure.
[0018] To manufacture the invention, the layers are deposited in the order described in the previous paragraph and as shown in FIG. 1 .
[0019] The ferromagnetic layers all have an amorphous structure and are required to have a minimum thickness, particularly those films that contact the dielectric layer. A preferred material for contacting the dielectric layer is CoFeB. This has an amorphous structure when certain constituents exceed a certain concentration. An amorphous film is smoother than a film with crystalline structure since it has no preferred texture, but to fully utilize this smoothness, especially when grown on top of a crystalline film, the thickness needs to exceed a certain critical value.
[0020] Although CoFeB meets these criteria, it also has a relatively large magnetostriction constant (about 10 5 ). Accordingly, if we elect to use it for the layer on whose surface the tunneling layer is grown (i.e. AP1), the layer on the tunneling dielectric's other surface (i.e. the free layer) needs to have a magnetostriction constant of the opposite sign and approximately equal absolute value so the final structure has a net magnetostriction constant that is close to zero.
[0021] Materials that satisfy this requirement, as well as being suitable for use as a free layer, include CoB, CoNb, and CoNbHf. This arrangement works best with an alumina tunneling dielectric but when a magnesia tunneling dielectric is used, it is preferable to have CoFeB on both its surfaces. In that case, the free layer is a laminate of CoFeB and one or more of the materials already mentioned (CoB, CoNb, and CoNbHf), to a sufficient thickness to cause the full structure to have a magnetostriction constant very close to zero.
[0022] When Al 2 O 3 was used for the dielectric layer of a typical NiFe based TMR film, the dr/r is about 42%, Vbd about 1.50V and V 50 about 560 mV. With a (CoFe) 4 B film having the same dielectric thickness, the dr/r is about 73.2%, Vbd about 1.76V and V 50 about 780 mV, i.e. all have significantly improved.
[0023] When MgO was used for the dielectric layer, an MTJ with (CoFe) 4 B for both the free and pinned layers, a dr/r of about 230% was achieved. However, the magnetostriction of a CoFeB film is positive (+10 −5 ) which is too large for an MTJ free layer. Reducing the Fe content makes the magnetostriction smaller but reducing Fe content too much would cause a drop of dR/R. Since the magnetostriction of CoB, CoNb, CoNbHf, CoTa, and CoW, all range from −2×10 −6 to −8×10 −6 , these can be used directly on top of a CoFeB film to partially compensate for the positive magnetostriction of CoFeB, when forming an amorphous free layer having very small Hc. These results are summarized in TABLE I below:
TABLE I free and V bd V 50 dielectric pinned layers dR/R % volts mV alumina NiFe 42 1.50 560 alumina CoFeB 73.2 1.76 780 magnesia CoFeB 230 — —
where V bd is the breakdown voltage and V 50 is the voltage at which dR/R is reduced by 50% The fixed multilayers, comprising a 1st ferromagnetic layer's magnetization is substantially antiparallel to the magnetization of the 2nd ferromagnetic layer, these layers being separated by a thin layer of material such as (but not limited to) Rh, Ru, Cr, or Cu which serve to maintain strong antiparallel magnetic coupling between the two ferromagnetic layers, the magnetic moments of these two layers being closely matched so as to reduce any net moment of the fixed multilayer. An antiferromagnetic layer of (but not limited to) PtMn, NiMn, OsMn, IrMn, or PtPdMn is positioned immediately below AP2 in order to fix its magnetization direction uni-directionally. | An improved TMR device is disclosed. The ferromagnetic layers of the device, particularly those that contact the dielectric tunneling layer have an amorphous structure as well as a minimum thickness (of about 15 Å). A preferred material for contacting the dielectric layer is CoFeB. Ways of overcoming problems relating to magnetostriction are disclosed and a description of a process for manufacturing the device is included. | 6 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] Reference is made to the co-pending, commonly assigned, U.S. Provisional Patent Application Ser. No. 60/532,162 filed on Dec. 23, 2003, entitled: GLOSS AND DIFFERENTIAL GLOSS CONTROL MEHODOLOGY, the disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to controlling gloss and differential gloss, and more specifically, controlling gloss and differential gloss while maintaining flexibility in media selection, reducing differential gloss and image relief, improving fuser reliability and lifespan, and enhancing overall gloss control.
BACKGROUND OF THE INVENTION
[0003] In high-speed, high-quality electrophotographic printing applications, it may be desirable to get high gloss on the pictorial areas of an image but not on the text areas (i.e., differential gloss). As described in U.S. Pat. No. 5,234,783, issued to Ng, herein incorporated in its entirety by reference, this may be accomplished by selectively putting a transparent toner overcoat on the pictorial area. One example described in the Ng patent makes use of a lower viscosity toner so that there can be a higher gloss in the pictorial areas.
[0004] However, with high speed and high quality printing, there still can be disadvantages from the viewpoint of achieving higher gloss with heated roller fusing. For example, too much total toner coverage on the media may stress the fusing subsystem. Moreover, at the higher temperatures required to fuse a transparent toner overcoat along with the color toner lay-down, roller reliability as well as artifacts from the fuser roller oiler may become problematic. Additionally, there may also be problems relating to image relief differences between toner-covered areas versus adjacent areas without the transparent toner overcoat.
[0005] Other conventional systems to increase image gloss include an ultraviolet (UV) curable overcoat that may be applied over the total image or over, for example, only pictorial portions of the image. The UV curable overcoat may be applied by a conventional commercial printing coater or by ink jet printing, wherein a specific area may be coated selectively. However, with UV curable inks, even though image protection may be achieved over a wide variety of media, only certain types of coated media can benefit from the UV coating to lower differential gloss. In some cases, with uncoated matte media for example, differential glass can get worse with UV coating. Moreover, because most UV curable ink layers are a few microns thick, image relief may be quite visible on the dry electrophotographic prints.
[0006] As can be seen, there is a need for improved control of differential gloss on a wide variety of media substrates while minimizing image relief that may result from certain conventional differential gloss control methods.
SUMMARY OF THE INVENTION
[0007] As will be discussed in more detail below, a variety of technologies may be used to maintain flexibility in media selection, reduce differential gloss and relief, and improve fuser reliability and lifespan. These technologies include, for example, transparent toner overcoat, negative transparent toner masks, variable transparent toner screen mask, UV coater (off-line or ink jet), belt fusing, and transparent toner compensation for height relief. These technologies, when appropriately selected and applied, may be used to achieve overall appearance control for high quality and high-speed images.
[0008] The term “appearance” as used herein refers to those qualities well known in the art to those in the printing field. Such qualities include, for example, gloss, color density, differential gloss, and image relief.
[0009] The term “differential gloss” as used herein refers to the differences in image gloss among different portions of the same printed page.
[0010] The term “image relief” as used herein refers to differences in image surface heights along the same printed page.
[0011] The term “low differential gloss” as used herein refers to a difference in gloss value along a printed page of less than about 30 (in G60 units, for reference, please see Yee Ng, et al, “Standardization of Perceptual based Gloss and loss Uniformity for Printing Systems (INCITS W1.1)”, IS&T's 2003 PICS Conference Proceedings, pp. 88-93, 2003), in some instances less than about 20, and in other instances less than about 10.
[0012] The term “in-line” as used herein refers to a process occurring without user intervention, usually within the same apparatus as a previous process, while the term “off-line” as used herein refers to a process occurring after a break in the overall process, usually requiring the user to continue the process on a different apparatus or at a different location on the same apparatus.
[0013] In one aspect of the present invention, a method for controlling gloss and/or differential gloss of a printed image provides applying a color toner lay-down onto a media substrate to form a pre-fused image; applying a transparent toner over at least a portion of the pre-fused image to form a coated pre-fused image; fusing the coated pre-fused image to form a fused print; and finishing the fused print to increase a gloss value of the fused print.
[0014] In another aspect of the present invention, a method for controlling gloss and/or differential gloss of a printed image provides applying a color toner lay-down onto a media substrate to form a pre-fused image; applying a transparent toner over at least a portion of the pre-fused image as a negative mask to form a coated pre-fused image; selecting parameters for the negative mask to obtain a desired level of at least one of gloss, differential gloss and image relief; fusing the coated pre-fused image to form a fused print; and finishing the fused print to increase a gloss value of the fused print.
[0015] In yet another aspect of the present invention, a method for controlling gloss and/or differential gloss when creating a printed image on a printing device provides applying a color toner lay-down onto a media substrate to form a pre-fused image; fusing the coated pre-fused image to form a fused print; and finishing the fused print to increase a gloss value of the fused print.
[0016] In a further aspect of the present invention, a color image printing device provides a four-station color lay-down section for applying color toner to a media substrate to form a pre-fused image; a fifth station section for applying transparent toner to the pre-fused image; a fuser for fusing the pre-fused image into a fused image; and at least one of an in-line ink jet overcoat application device, an off-line ink jet overcoat application device, an in-line ultraviolet overcoat application device, and an off-line ultraviolet overcoat application device for increasing a gloss value of the fused image.
[0017] In still another aspect of the present invention, a computer readable media for controlling at least one of gloss and differential gloss of a printed image on a substrate provides a code segment for obtaining a desired level of gloss and differential gloss from a user; a code segment for reading an original image from which the printed image is to be made and calculating a color toner lay-down of the original image; a code segment for calculating an appropriate negative mask application of transparent toner based on at least one of the color toner lay-down of the original image, the desired level of gloss and differential gloss and the substrate.
[0018] These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 shows a schematic sketch of a paper path through a printing device according to the present invention;
[0020] FIGS. 2A and 2B shows methods for controlling differential gloss on glossy coated paper according to one embodiment of the present invention;
[0021] FIG. 3 shows methods for controlling differential gloss on matte coated paper according to one embodiment of the present invention;
[0022] FIG. 4 shows a graph illustrating the exemplary amount of clear ink to be used versus the amount of color toner to achieve image features according to the present invention; and
[0023] FIG. 5 shows a graph illustrating gloss uniformity when applying the negative mask method according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The following detailed description is of the best currently contemplated modes of carrying out the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.
[0025] Broadly, the present invention provides for the controlling of differential gloss of a printed image while minimizing the negative effects of image relief. Conventional methods may use a transparent toner overcoat to achieve low differential gloss, high overall gloss, and image protection. However, often times conventional methods result in image relief that is unacceptable to the end customer. Further, the amount of transparent toner overcoat needed may stress the heated fuser roller, as an increase in the amount of transparent toner overcoat results in an increase in the amount of heat needed to fuse the toner (color lay-down plus transparent overcoat) onto the media substrate. By using a variety of technologies according to the present invention, such as transparent toner overcoat, negative transparent toner masks, variable transparent toner screen masks, UV coater (off-line or ink jet), belt fusing, and transparent toner compensation for height relief, one may achieve high overall image gloss and low differential gloss as well as protection for the fused image.
[0026] Referring to FIG. 1 , there is shown a schematic sketch of a paper path 500 through a printing device 510 according to the present invention. Along paper path 500 there may be disposed a four-color toner lay-down section 520 for laying colored toner onto a substrate 502 to form a pre-fused image. Next, along paper path 500 , there may be disposed a fifth section, transparent toner lay-down section 530 , for laying down transparent toner onto the pre-fused image. Once transparent toner is laid down, the substrate 502 may be fused with a roller fuser 540 to produce a fused image. Following fusing, a post-fusing finishing step may include at least one of an in-line ink jet overcoat application device, an off-line ink jet overcoat application device, an in-line ultraviolet overcoat application device, and an off-line ultraviolet overcoat application device (each of these devices may be present in section 550 ) for increasing a gloss value of the post-fused image. Finally, the finished image may be further processed through a belt fuser 560 for further increasing the gloss value of the final product.
[0027] Referring to FIGS. 2A and 2B , there is shown a flow chart for various methods of differential gloss control using a glossy coated paper substrate 200 . After the conventional, well-known process of laying down the four-color toner 202 , the process of the present invention sub-processes into one of four main sub-processes—A, B, C, and D. Broadly, and as will be discussed in more detail below, sub-process A uses an ink jet or ultraviolet overcoat either in-line or off-line to generate a high gloss, low differential gloss, high relief image print. Sub-process B uses the printer's fifth station to apply an ink jet overcoat to obtain a similar (to sub-process A) high gloss, low differential gloss, high-relief image print. Sub-process C uses the printer's fifth station to lay down a negative mask transparent toner layer following four-color toner lay-down. Finally sub-process D uses the printer's fifth station to lay down a layer of transparent toner over the entire surface of the image.
[0028] In the case of glossy coated media 200 , after color toners were laid down (step 202 ) by the four color stations, the toned image can be fused (step 204 in sub-process A or step 210 in sub-process B) by regular heated roller fusing at high speed to get to a certain degree of gloss. Alternatively, the toned image may be fused with a smooth belt fuser to get to even higher gloss. One example of heated roller fusing may be found in U.S. Pat. No. 5,956,543. Examples of belt fusing may be found in U.S. Pat. Nos. 5,666,592; 5,890,032; and 5,887,234. Each of these patents is herein incorporated in their entirety by reference.
[0029] Due to different gloss levels of coated media, only a small number of media types are able to produce a relatively uniform gloss (i.e., small differential gloss, for example a differential gloss less than about 20) with varying amounts of toner coverage.
[0030] One method, as shown in sub-process A, to enhance overall image gloss while minimizing differential gloss may include using an in-line or off-line UV overcoat, as shown in step 206 , that may be applied to the fused images (after step 204 ). Due to the similar level of adsorption of the UV overcoat into the coated media with respect to the toner-covered area, high gloss with low differential gloss can be achieved. High adjustable gloss (for example, a gloss value greater than 60) can be achieved with the proper selection of UV curable ink while maintaining low differential gloss. Image protection may also be achieved by this method. UV curable inks are known in the art for both image protection and imparting gloss. Examples of UV curable ink may be found in U.S. Pat. No. 5,371,058, issued to Wittig et al., herein incorporated in its entirety by reference.
[0031] However, because the UV overcoat can be quite thin (˜2 μm) compared with the toner coverage (for example, 280% maximum total four-toner coverage), high relief images can be seen. An appearance of larger color gamut may be achieved due to the increase in gloss. Therefore, lower toner coverage may be used to obtain a similar gamut compared with the original four-color toned images with this overcoat technique, thereby reducing relief images.
[0032] Another method, as shown in sub-process B, to accomplish a similar result as above (i.e., high gloss, low differential gloss, high relief image, and image protection) may include using an ink jet with UV ink, as shown in step 212 , in the fifth station of the high speed printer. Because an ink jet application method is used, this method has the added advantage of being able to selectively gloss some of the image elements on every page. With the proper selection of UV curable ink, high gloss, some adjustable gloss (from varying the locations and amounts of ink jet UV curable ink lay-down), and low differential gloss can be obtained on coated glossy media. Of course, like the UV overcoat method of sub-process A previously discussed, the method of sub-process B also may produce high relief images on the toner-covered images. However, lower toner coverage may be possible to obtain a similar gamut compared with the original four-color toned image with the ink jet overcoat technique. Inks other than UV curable ink, such as thermal cross-linkable ink, can also be used for this purpose.
[0033] As shown in sub-process D, transparent toner overcoat may be used in the fifth station of the high-speed printer as shown in step 230 . Regular heated roller fusing (step 232 ) may then be used to obtain a certain degree of uniform (i.e., lower differential gloss as compared to the four-color images) adjustable gloss in the printed image. Lower relief, as compared with the UV overcoat methods (sub-processes A and B) previously discussed, can be achieved due to the larger layer thickness (for example, >2 μm) of the toner overcoat. However, due to the thick transparent toner overcoat layer, in-line heated roller fusing may not have sufficient power to achieve a high gloss image. Gloss enhancements, after fusing the transparent toner overcoat, may be accomplished by either in-line ink jet UV system/curer or an off-line UV ink coater/curer, as shown in step 224 . In this case, a wide range of paper may be used without the problem of differential surface adsorption (between toner laid down areas and non-toner laid down areas), since now the adsorption surface onto which the UV curable ink is applied is defined by the transparent toner overcoat surface rather than the paper surface (which may have varying surface adsorptions). Gloss enhancement may also be achieved in the above-described sub-process D by using a belt fuser on the previously roller-fused image (also shown in step 224 ). Alternatively, as shown in sub-process D′, overall gloss may be enhanced by using a high gloss special paper that has a softenable, polymer-based overcoat that the toner can be buried within. Fusing (roller-fusing with optional belt fusing) of this special paper, as shown in step 234 , with the transparent toner overcoat layer may achieve a printed image with low differential gloss and low relief image.
[0034] Referring still to FIGS. 2A and 2B , sub-process C may use a fifth station negative mask transparent toner at step 220 to achieve high gloss for high speed printing applications. A negative transparent toner mask is the negative of the four-color image in terms of toner height, so the overall toner image height is uniform across the page. Because the original image is known, the toner lay-down coverage may be calculated by any well-known method in the art. From this calculation, the amount of transparent toner negative mask may be determined based upon the user's desired gloss, differential gloss and image relief, by using, for example, the curve of FIG. 4 , as described in more detail below. After application of the negative mask transparent toner in step 220 , the image may be fixed or fused in step 222 (sub-process C) or step 226 (sub-process C′).
[0035] If higher gloss is desired, then an in-line or off-line ink jet UV system/curer or regular UV coater/curer can be used, as shown in step 228 , to bring up the overall gloss of the image while still retaining the low differential gloss and low relief images. Another method for increasing the overall image gloss may include using a post-press belt fuser, as shown in step 224 and as previously described. A further method for obtaining in-line gloss enhancement of low differential gloss and low relief images at high speed is to use an in-line ink jet UV overcoat system, as shown in step 228 .
[0036] While FIGS. 2A and 2B shows each of these methods (sub-processes A, B, C, and D) as leading to a single result, a combination of methods may be used. For example, the glossy coated paper may be passed through fifth station negative mask transparent toner in step 220 , coated with an ink jet or UV overcoat, as shown in step 228 , and then passed through a belt fuser, as shown in step 224 , to achieve high gloss and low differential gloss.
[0037] Referring to FIG. 3 , there is shown a flow chart for various methods of differential gloss control using a matte coated paper substrate 300 having a gloss value from about 5 to about 10. As shown in step 302 , a four-color toner lay-down is applied to the matte coated paper substrate. Next, following sub-process F, either a fifth station ink jet overcoat, an in-line or off-line ink jet overcoat, or an in-line or off-line UV overcoat may be applied as shown in step 304 to give a printed image having image protection with some control of differential gloss (for example, a differential gloss from about 20 to about 20). To resolve this problem of differential gloss with matte coated paper, as shown in sub-process G, a transparent toner may be used in the fifth station (either as an overcoat or as a negative mask) (step 310 ) in conjunction with an ink jet or UV overcoat (step 312 ) to get high gloss with the less expensive matte paper, as shown in step 314 . Optionally, to further increase the gloss of the finished product, the fused image may pass through a post-press belt fuser.
[0038] Referring now to FIG. 4 , there is shown a graph of the amount of clear ink (transparent toner) usable in conjunction with the amount of four-color lay-down (% CMYK) in order to achieve certain results. More specifically, based on the user's selection of at least one of desired gloss, desired differential gloss and desired relief image, the graph of FIG. 4 , according to one method of the present invention, may help determine the negative mask calculations required in step 220 of FIG. 2 .
[0039] Alternatively, the determination of the negative mask calculations required in step 220 of FIG. 2A may be determined, in one embodiment of the present invention, by computer software encoded on a computer readable media. The computer software may have a code segment for obtaining a desired level of gloss and differential gloss from a user, reading an original image from which the printed image is to be made and calculating a color toner lay-down of the original image, and calculating an appropriate negative mask application of transparent toner based on at least one of the color toner lay-down of the original image, the desired level of gloss and differential gloss and the substrate.
[0040] Line 420 shows the desired negative mask calculation to achieve minimum color impact while matching substrate gloss for a glossy coated paper of intermediate level of gloss. In other words, if the user desires a print that would have a gloss value similar to the substrate gloss value, the amount of transparent toner negative mask to use on the substrate varies with the amount of four-color ink based on this curve.
EXAMPLES
[0041] Referring to FIG. 5 , there is shown a graph illustrating gloss uniformity when applying the negative mask method according to the present invention. The x-axis of the graph represents various color patches of a printed image, having varying percentages of color lay-down. The y-axis shows the gloss value. For these experiments, a glossy coated paper was used (Lustro Gloss 118) and two different transparent toner negative mask models were used to obtain a maximum gloss of 40 (square-indicated graph) and a maximum gloss of 50 (triangle-indicated graph). The results show that, with no transparent toner negative mask, the gloss value varied from about 20 to about 40 (a differential gloss of about 20). Using the negative mask model of the present invention, the gloss varied from about 35 to about 40 with the NMaxG40 negative mask model and from about 35 to about 50 with the NMaxG50 negative mask model. As can be seen, lower differential gloss and high overall gloss may be achieved by the negative mask method according to the present invention.
[0042] It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.
Parts List
[0000]
A, B, C, D, F, and G sub-processes
200 glossy coated paper substrate
202 four-color toner lay-down step
204 fusing step
206 in-line/off-line UV overcoat step
210 fusing step
212 fifth station ink jet step
220 fifth station negative mask transparent toner step
222 fusing step
224 in-line/off-line ink jet/UV coat step
226 fusing step
228 in-line ink jet UV overcoat step
230 fifth station transparent toner overcoat step
232 fusing step
234 fusing step
300 matte coated paper
302 four-color toner lay-down step
310 fifth station transparent toner lay-down step
312 ink jet or UV overcoat
314 result step
420 minimum color impact/match substrate gloss line
500 paper path
502 substrate
510 printing device
520 four-color lay-down section
530 fifth-section transparent toner lay-down section
540 roller fuser
550 section (for post-finishing step)
560 belt fuser | Gloss, differential gloss, and image relief of a printed image may be controlled by utilizing a combination of technologies in the appropriate manner. These technologies include the use of transparent toner overcoats, negative transparent toner masks, variable screen transparent toner screen masks, UV coaters, and post-press belt fusing. Unlike conventional systems, which may increase gloss at a cost of also increasing image relief, the present invention may produce an image having a controlled gloss, differential gloss, and image relief. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an antitheft method for a vehicle having an immobilizer which prohibits the engine from starting when a key with an ID code, which does not match an ID code previously registered in a controller mounted on the vehicle is used and to a method and device for providing an antitheft operation in the event a person attempts to defeat the theft by replacement of the controller.
[0002] Typical antitheft devices for vehicle as shown the U.S. Pat. Nos. 6,525,433 and 6,683,391 and co-pending U.S. application Ser. No. 10/707689, filed Jan. 5, 2004, of the assignee hereof and comprises a key cylinder and a controller on a vehicle body, that control an ignition immobilizer. The operation is such that when a key having a built-in transponder is inserted into the key cylinder, the controller performs an ID check through a circuit that communicates with the transponder via an antenna located in the vicinity of the key cylinder to read an ID code of the key. The immobilizer only permits the engine to start if the ID code matches the one previously registered in the controller.
[0003] In accordance with the disclosure thereof backup power is constantly supplied to the immobilizer generally through the vehicle battery even when the vehicle is not running. Thus even when the main switch is off the immobilizer is kept in an alert mode for theft through illegal means.
[0004] When a vehicle is equipped with such an antitheft device, the engine cannot be started without a key with an ID code which matches the ID code previously registered in the controller. Thus, the vehicle cannot be illegally driven by someone other than the owner of the vehicle and is prevented from being stolen.
[0005] However, such an antitheft device are commercially available and the coupler for coupling the device and the on-board battery is a standardized product. Therefore a prospective thief can steal the vehicle by removing the entire antitheft device could be removed and replacing it with another device that matches a key possessed by the prospective thief.
[0006] One conventional preventive measure against such theft of a vehicle is to make it difficult to steal the vehicle by complicating the structure in which an antitheft device is attached to the vehicle, for example, by increasing the number or types of attaching devices or encasing the device, so that it cannot be removed quickly. However these remedies add to the cost of both assembly and servicing and also can be defeated by skilled thieves.
[0007] Therefore it is a principal object of this invention to provide an easily attached, serviced and removed system and method of antitheft protection that nevertheless makes it difficult to remove the device within a short period of time.
[0008] It is a further an object of the invention is to provide antitheft method and device for a vehicle which does not complicate the structure of the attachment but nevertheless prevents theft.
SUMMARY OF THE INVENTION
[0009] A first feature of the invention is adapted to be embodied in an antitheft method for a vehicle equipped with an immobilizer having a controller which transmits an ignition prohibition canceling signal to an ignition control unit of an engine when an ID code of a transponder built in a key matches an ID code previously registered in the controller on the vehicle. The method comprises the steps of maintaining the ignition control unit in an ignition prohibition mode for a predetermined period of time after the immobilizer has been disconnected from a power source and is subsequently connected to a backup power source.
[0010] Another feature of the invention is adapted to be embodied in an antitheft device for a vehicle having an engine comprising an immobilizer having a controller that checks an ID code of a transponder built in a key against an ID code previously registered in the controller. A timer circuit counts the connection time that has elapsed after the immobilizer has been disconnected from a power source and is connected to a backup power source for prohibiting starting of said engine when the connection time is shorter than a predetermined period of time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a schematic view illustrating the components of an embodiment of the invention.
[0012] FIG. 2 is a block diagram illustrating the embodiment
[0013] FIG. 3 is a circuit diagram of the antitheft device.
[0014] FIG. 4 is a flowchart illustrating the operation of the device and its method.
DETAILED DESCRIPTION
[0015] Referring now to the drawings and initially to FIGS. 1 and 2 these illustrate the configuration of an antitheft device of the present invention. The antitheft device of the present invention is comprised of a vehicle mounted immobilizer 11 connected to an on-board battery 12 with a voltage of 12V, for example, an ignition control unit (ECU) 13 , a key cylinder assembly, indicated generally at 14 , and a cooperating key 15 . The immobilizer 11 has an antenna 16 , generally incorporated in the body of the key cylinder 14 , and a controller, indicated generally at 17 . The antenna 16 and the controller 17 may be integrated with each other.
[0016] A main switch 18 is built in a key cylinder 14 . When the appropriate key 15 is inserted into the key cylinder 14 and operated, the main switch 18 is turned on or off. In addition to its keying, if employed, the key 15 has a built-in transponder 19 in which a unique ID code is recorded.
[0017] The controller 17 is formed on a printed circuit board and has an ID reading circuit 21 , a CPU 22 , a power source circuit 23 , a timer circuit 24 and a memory 25 . The controller 17 is connected to the antenna 16 and the ignition control unit, and has a function of communicating with the transponder 19 built in the key 15 and the ignition control unit 13 of an engine 12 . The ignition control unit may be incorporated in the controller 17 . The battery 12 is connected to the immobilizer 11 via a coupler 26 ( FIG. 3 ) as described later, and supplies backup power with a low voltage (5V, for example) to keep the controller 17 operational regardless of the on or off condition of the main switch 18 .
[0018] When the key 15 is operated and the main switch 18 is turned on, the battery 12 is connected to load components such as lights and an ignition circuit (not shown), and an ID code signal is transmitted from the key 15 to the controller 17 via the antenna 16 of the key cylinder 14 .
[0019] The timer circuit 24 counts the connection time, that is, the amount of time which has elapsed after the last initial connection of the immobilizer 11 to the battery 12 (the amount of time from the point at which the backup power starts to be supplied from the battery 12 by connecting the coupler 26 ). Since backup power is kept supplied to the immobilizer 11 even when the main switch is off, the timer circuit 24 can count the connection time after the immobilizer 11 has been attached.
[0020] The immobilizer 11 is programmed not to read the transponder 19 even if the key 15 is turned to the on position until a predetermined period of time elapses. Each of the immobilizer 11 and the ignition control unit 13 is connected to the on-board battery 12 via a respective coupler 26 as shown in FIG. 3 , and the counting of the connection time is automatically started when the immobilizer 11 is connected to the coupler 26 . Although shown separately in FIG. 3 , the couplers 26 may be contained in a common body. Thus, the connection time cannot be changed illegally from the outside.
[0021] The ignition control unit 13 may be also counted the connection time and controlled not to be activated until a predetermined period of connection time elapses as in the case with the immobilizer 11 .
[0022] The ID code recorded in the transponder 19 of the key 15 is recorded in the memory 25 , and the CPU 22 determines whether the ID code, read by the ID reading circuit 21 when the key 15 is inserted into the key cylinder 14 , matches the ID code recorded in the memory 25 . When the ID codes match with each other, an ignition prohibition canceling signal is transmitted from the CPU 22 to the ignition control unit 13 to activate the ignition control unit 13 , allowing a starter motor 27 and ignition coil 28 of the of an associated engine 29 to start.
[0023] When the ID codes do not match with each other, the ignition control unit 13 is maintained in an ignition prohibition mode and the engine 29 cannot be started. At this time, an alarm or indication lamp indicates the improper operation.
[0024] The implementation procedure of the present invention will be described with reference to FIG. 4 . When the key 15 is inserted into the key cylinder 14 at the step S 1 ) and turned to the on position, the main switch 18 is turned on and the controller 17 detects this at the step S 2 . The controller 17 then determines at the step S 3 whether a predetermined period of time has elapsed after the connection of the immobilizer 11 to the on-board battery 12 via the coupler 26 . If the connection time is determined to be insufficient, jumps to the step S 8 and no further operations are performed and the engine 29 cannot be started.
[0025] If, however, the predetermined period of time has elapsed, the program moves to the step S 4 where an ID code check is performed. Radio waves are transmitted from the battery 12 to the key 15 via the antenna 16 to supply electric power to the transponder 19 to perform the ID code check. When a predetermined amount of electric power is charged in the transponder 19 , the unique ID code of the transponder 19 is transmitted to the controller 17 via the antenna 16 . The controller 17 reads the ID code with the ID reading circuit 21 and transmits it to the CPU 22 , where the read ID code is compared with the ID code registered in the memory 25 to determine whether they match with each other, that is, whether the key is the correct key for the controller 17 at the step S 5 .
[0026] If the key 14 is determined to be the correct key, a canceling signal for canceling the start prohibition mode of the engine 29 and permitting the engine 29 to start is transmitted to the ignition control unit at the step S 6 . Then at the step S 7 the ignition control unit starts the engine 29 .
[0027] On the other hand the code is different from the previously registered ID code, the key is determined to be an incorrect key and the engine 29 is maintained in the start prohibition mode by jumping to the step S 8 . Then, the operation is completed.
[0028] Alternatively, the step S 3 may be programmed to be performed after the step S 5 . That is, the determination of the connection time of the backup power source may be conducted after the ID check.
[0029] As described above, the vehicle cannot be illegally driven by someone other than the owner of the vehicle having the correct key 15 . Even if the immobilizer 11 mounted on the vehicle is illegally removed and replaced with a new one, the vehicle cannot be driven within a short period of time due to the necessity of the time set at step S 3 is reached. Thus, it is very difficult to steal the vehicle during temporary parking.
[0030] When the key 15 is turned to the off position to turn off the main switch and then removed from the key cylinder 14 after the vehicle has been stopped, the engine 29 is stopped but backup power is kept supplied to the controller 17 .
[0031] Thus from the foregoing description it should be readily apparent that the described constructions and methods a very effective and difficult to defeat vehicle antitheft protection is provided without interfering with the simplicity of instillation and servicing as well as reducing the cost thereof. Of course those skilled in the art will readily understand that the described embodiments are only exemplary of forms that the invention may take and that various changes and modifications may be made without departing from the spirit and scope of the invention, as defined by the appended claims. | Simple but very effective vehicle antitheft methods and apparatus that avoid theft by replacement of the antitheft device by determining the time it has been before the device is powered up and prohibiting starting if it is not long enough. | 4 |
BACKGROUND OF THE INVENTION
With the proliferation of digital camera technology higher resolution digital cameras are finding their way into more and more consumer electronics. Mobile devices such as cellular or mobile telephones and other portable wireless devices, have benefited from the improved compactness and increased resolution of small digital cameras. This is evident from the increased number of mobile devices that incorporate a digital camera.
However, ergonomics, portability and power consumption can constrain the size of a display incorporated in a mobile device. Even with increased resolution of portable displays, high-resolution digital cameras can necessitate resizing an image on a mobile device in order to fit the entire image on the display. Similarly, in order to display details that can be captured by high-resolution digital camera devices, it may be necessary to resize a portion of the image on a portable electronic device's display. Constrained with often-limited processing capacity of mobile devices, many image resizing processes scale an image from the upper left corner of the image. Unfortunately, scaling from the upper left corner can result in the bottom and right edge of the image not being visible on the display.
In view of the forgoing, there is a need for a center based image resizer.
SUMMARY
In one embodiment, a method for resizing image data from a first size image to a second size image is disclosed. In one operation of the method, a scale factor is determined based on a number of gaps between pixels in the first size image and a number of gaps between pixels in the second size image. In another operation, the scale factor is applied to the first size image to generate a representation of the second size image data. In yet another operation a remainder representing an offset from a last pixel of the first size image data and a last pixel from the representation of the second size image data is determined. With the offset determined, another operation offsets each end pixel of a line of the second size image data by a portion of the remainder.
In another embodiment a method for center-based image resizing is disclosed. In one operation a scale factor is determined based on a number of gaps between pixels in the first size image and a number of gaps between pixels in the second size image. In another operation a vertical remainder is determined, the vertical remainder representing a difference between a last pixel position of the first size image and a last pixel position of the second size image. In yet another operation, a vertical offset is determined for the second size image based on a proportion of the remainder. With the vertical offset determined, another operation applies the scale factor and vertical offset to vertical pixels in the first size image. In still another operation, a horizontal remainder is determined, the horizontal remainder representing a difference between a last pixel position of the first size image and a last pixel position of the second size image. Similar to the vertical offset, a horizontal offset can be determined for the second size image based on a proportion of the remainder. In another operation, the scale factor and horizontal offset are applied to horizontal pixels in the first size image.
In yet another embodiment, a resizer for scaling image data is disclosed. The resizer can include a vertical accumulator. The vertical accumulator can be configured to apply a scale factor based on a number of gaps between vertical pixels in the first image size and a number of gaps between vertical pixels in the second image size. The resizer can also include a horizontal accumulator. The horizontal accumulator can be configured to apply the scale factor based on a number of gaps between horizontal pixels in the first image size and a number of gaps between horizontal pixels in the second image size. Wherein a center based scaled image is output from the resizer based on the scale factor.
Other aspects and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention, together with further advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings.
FIG. 1 is a simplified schematic diagram illustrating a high level architecture of a device implementing a center based image resizer in accordance with one embodiment of the present invention.
FIG. 2 is a simplified schematic diagram illustrating a high level architecture for the graphics controller 106 in accordance with one embodiment of the present invention.
FIG. 3 is a high level schematic illustrating elements within the resizer module 206 , in accordance with one embodiment of the present invention.
FIG. 4A illustrates an original image having a width of five pixels, represented by original pixels O 0 -O 4 that will be scaled to a resized image having eight pixels N 0 -N 7 , in accordance with one embodiment of the present invention.
FIG. 4B illustrates pixel spacing between the resized image pixels in accordance with one embodiment of the present invention.
FIG. 4C illustrates correcting the offset caused by the remainder value in accordance with one embodiment of the present invention.
FIG. 4D illustrates the result of center-based image resizing when an original image is resized to a smaller size, in accordance with one embodiment of the present invention.
FIG. 5 is a flowchart illustrating the operations that perform center based resizing in accordance with one embodiment of the present invention.
DETAILED DESCRIPTION
An invention is disclosed for a center-based image resizer capable of scaling images from a first size to a second size based on a central point of the first size. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order not to unnecessarily obscure the present invention.
FIG. 1 is a simplified schematic diagram illustrating a high level architecture of a device 100 implementing a center based image resizer in accordance with one embodiment of the present invention. The device 100 includes a processor 102 , a graphics controller or Mobile Graphic Engine (MGE) 106 , a memory 108 , and an Input/Ouput (I/O) interface 110 , all capable of communicating with each other using a bus 104 .
Those skilled in the art will recognize that the I/O interface 110 allows the components illustrated in FIG. 1 to communicate with additional components consistent with a particular application. For example, if the device 100 is a portable electronic device such as a cell phone, then a wireless network interface, random access memory (RAM), digital-to-analog and analog-to-digital converters, amplifiers, keypad input, and so forth will be provided. Likewise, if the device 100 is a personal data assistant (PDA), various hardware consistent with a PDA will be included in the device 100 .
The processor 102 performs digital processing operations and communicates with the MGE 106 . The processor 102 is an integrated circuit capable of executing instructions retrieved from the memory 108 . These instructions provide the device 100 with functionality when executed on the processor 102 . The processor 102 may also be a digital signal processor (DSP) or other processing device.
The memory 108 may be random-access memory or non-volatile memory. The memory 108 may be non-removable memory such as embedded flash memory or other EEPROM, or magnetic media. Alternatively, the memory 108 may take the form of a removable memory card such as ones widely available and sold under such trade names such as “micro SD”, “miniSD”, “SD Card”, “Compact Flash”, and “Memory Stick.” The memory 108 may also be any other type of machine-readable removable or non-removable media. Additionally, the memory 108 may be remote from the device 100 . For example, the memory 108 may be connected to the device 100 via a communications port (not shown), where a BLUETOOTH® interface or an IEEE 802.11 interface, commonly referred to as “Wi-Fi,” is included. Such an interface may connect the device 100 with a host (not shown) for transmitting data to and from the host. If the device 100 is a communications device such as a cell phone, the device 100 may include a wireless communications link to a carrier, which may then store data on machine-readable media as a service to customers, or transmit data to another cell phone or email address. Furthermore, the memory 108 may be a combination of memories. For example, it may include both a removable memory for storing media files such as music, video or image data, and a non-removable memory for storing data such as software executed by the processor 102 .
FIG. 2 is a simplified schematic diagram illustrating a high level architecture for the graphics controller 106 in accordance with one embodiment of the present invention. The graphics controller 106 can accept input to host interface module 200 . For example, the host interface module 200 can receive pixel data to be processed by the graphics controller 106 . As previously discussed, the graphics controller 106 can also be referred to as an MGE or alternatively, a Liquid Crystal Display Controller (LCDC) or a Graphics Processing Unit (GPU). Additionally, the host interface module 200 can also receive various signals to synchronizing various buses and clocks to ensure proper communications to other components of the device. The host interface 200 can also bi-directionally communicate with a register 202 . The register 202 can broadly be defined as a storage area for hardware input/output. Though the register 202 is shown as a single module, in other embodiments registers can be distributed throughout the graphics controller 106 . Registers can be associated with components of the graphics controller 106 that are illustrated in FIG. 2 along with additional components that are not illustrated for simplicity. Also connected to the host interface 200 is a memory frame buffer 204 . The memory frame buffer 204 can broadly be defined as a storage area for pixel data. In one embodiment, the memory frame buffer 204 can be a first-in-first-out (FIFO) buffer. Other embodiments can use different types or techniques to buffer pixel data. One skilled in the art should recognize that the examples provided are intended to be exemplary and do not limit the scope of this disclosure.
A resizer module 206 can receive pixel data from the memory frame buffer 204 and includes logic capable of calculating and manipulating pixel data to resize an image based on a center of the image. The resizer module 206 can resize an image based on manipulating the distance, or gaps, between adjacent pixels. As will be described in further detail below, decreasing the distance between adjacent pixels, results in zooming in on an image. Conversely, increasing the distance between adjacent pixels results in zooming out of an image. Pixel data for the resized image can then go to a display pipe 208 . Broadly defined, the display pipe 208 is a memory capable of storing pixel data for the resized image. In one embodiment, the display pipe 208 can be a FIFO buffer. Connected to the display pipe 208 is a display interface 210 . The display interface 210 can be used to manipulate pixel data from the display pipe 208 so it can be properly formatted for a display device 212 . In some embodiments, the display device 212 can integrated into the device such as displays for mobile phones, portable video game systems and smartphones. In other embodiments, the display device 212 can be external to the device requiring an external connection such as a discrete computer monitor.
FIG. 3 is a high level schematic illustrating elements within the resizer module 206 , in accordance with one embodiment of the present invention. As shown in FIG. 3 , data processed by the resizer 206 first pass through a vertical accumulator 300 and then a horizontal accumulator 302 before being stored in a memory 304 . Note that in other embodiments, data can be processed by the horizontal accumulator, passed to the vertical accumulator and then stored in a memory. Alternatively, other permutations are possible where a separate memory is maintained for each accumulator.
FIGS. 4A-4D illustrate changes in horizontal pixel spacing calculated using the horizontal accumulator of the center-based resizer to display new pixels N 0 -N 7 from original pixels O 0 -O 4 , in accordance with one embodiment of the present invention. In one embodiment of the center-based resizer calculations for pixel placement of a resized image are based on the number of gaps between pixels of an original image and the number of gapes between pixels in the resized image. For example, if the original image has X pixels in a row or column, then there are X−1 equally spaced gaps between the pixels. Similarly, resizing an image with Y pixels in a row or column means there are Y−1 gaps.
FIG. 4A illustrates an original image having a width of five pixels, represented by original pixels O 0 -O 4 that will be scaled to a resized image having eight pixels N 0 -N 7 , in accordance with one embodiment of the present invention. As this is a center based resizer, all attempts will be made to align the first (N 0 ) and last (N 7 ) new pixels of the resized image with the location of the first (O 0 ) and last (O 4 ) pixels of the original image shown in FIG. 4A . Thus, the original pixels are separated by four equally spaced gaps whereas the resized image will have seven equally spaced gaps.
FIG. 4B illustrates pixel spacing between the resized image pixels in accordance with one embodiment of the present invention. To determine the resized pixel spacing, a scale factor for this particular embodiment is calculated using the following formula:
scale factor=(original width−1)/(resized width−1)
Using fixed point math, with seven bits of integer and nine bits of decimal, the scale factor calculation becomes:
scale factor=2 9 Δ(original width−1)/(resized width−1)=512Δ( 4/7)=292remainder4
Where the 2 9 is used to calculate the nine bits of decimal. Thus, spacing between the resized image pixels N 0 -N 7 is calculated. Note that alternative values of integer and decimal values can be used when calculating the scale factor. One skilled in the art should recognize that the values provided above are intended to be exemplary and should not be construed to limit the claims. Because of the finite precision of the calculation in hardware, some scale factors will not be calculated as integers resulting in a leftover remainder. A scale factor with a remainder means that the last pixel of the resized image will be misaligned with the last pixel of the original image. The amount of misalignment means the resized image will not be perfectly centered because the last pixel of the resized image and the last pixel of the original image is offset by the remainder value.
FIG. 4C illustrates correcting the offset caused by the remainder value in accordance with one embodiment of the present invention. To correct for the offset, the position of the first pixel of the resized image can be shifted by a value that is half of the remainder, or:
offset=(remainder)/2
Thus, using the values of the current example results in the first pixel of the resized image being offset by two. Dividing the remainder by two results in the offset centering the resized image. In other embodiments it may be desirable to calculate the offset by dividing the remainder by a value other than two. While this can result in the resized image no longer appearing centered on a display in relation to the original image, the resized image will still be resized proportionally based on the gaps between pixels. In alternative embodiments, the scale factor can be further defined as a vertical scale factor and a horizontal scale factor. In embodiments where the horizontal and vertical scale factors are not identical, it is possible that the resized image will be distorted because of the asymmetric scale factors.
FIG. 4D illustrates the result of center-based image resizing when an original image is resized to a smaller size, in accordance with one embodiment of the present invention. In this example, the original image has a width of five pixels and the resized image has a width of four pixels. Using the fixed point math formula to determine scale factor results in:
scale factor=2 9 Δ(original width−1)/(resized width−1)=512Δ( 4/7)=682remainder2
As there is a remainder, to correct for the misalignment of the last pixel, the first pixel can be offset by half of the remainder, or one.
One skilled in the art should note that the techniques discussed to illustrate calculations of the horizontal accumulator in FIG. 4A-4D can also be applied to the vertical accumulator using columns of pixels separated by a vertical pixel spacing.
FIG. 5 is a flowchart illustrating the operations that perform center based resizing in accordance with one embodiment of the present invention. Operation 500 , START beings in the procedure. Operation 502 loads pixel data for an original image, the pixel data including pixel location data, for the original image. In operation 504 , a scale factor is determined based on the desired resized image. In the embodiment illustrated in FIG. 5 , the resized image will be positioned to appear centered relative to the original image after being resized. In order to center the resized image relative to the original image, operation 506 determines whether the scale factor calculation results in a remainder.
If the resized image results in a remainder, operation 508 is used to determine an offset value. Operation 510 adjusts the scaled pixel data by the offset value calculated in operation 508 while operation 512 applies the scale factor to the pixel data of the original image. In other operations, operation 514 stores the pixel data for the resized image in a memory location while operation 516 terminates the procedure. Note that in embodiments where the resized image does not need to be centered relative to the original image, operations 508 - 512 do not need to be performed.
If operation 506 determines that the scale factor will not result in a remainder, operation 512 applies the scale factor to the pixel data for the original image. In other operations, operation 514 stores the pixel data for the resized image in a memory location and operation 516 terminates the procedure.
It will be apparent to one skilled in the art that the functionality described herein may be synthesized into firmware through a suitable hardware description language (HDL). For example, the HDL, e.g., VERILOG, may be employed to synthesize the firmware and the layout of the logic gates for providing the necessary functionality described herein to provide a hardware implementation of the resizing techniques and associated functionalities.
Although the foregoing invention has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the appended claims. Accordingly, the present embodiments 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 and equivalents of the appended claims. | A method for resizing image data from a first size image to a second size image is disclosed. In one operation of the method, a scale factor is determined based on a number of gaps between pixels in the first size image and a number of gaps between pixels in the second size image. In another operation, the scale factor is applied to the first size image to generate a representation of the second size image data. In yet another operation a remainder representing an offset from a last pixel of the first size image data and a last pixel from the representation of the second size image data is determined. With the offset determined, another operation offsets each end pixel of a line of the second size image data by a portion of the remainder. | 6 |
CROSS-REFERENCES TO RELATED PATENT APPLICATIONS
[0001] The subject matter described in the present application is related to that described in the U.S. Patent Application No. 61/246,499 to Valencia filed Sep. 28, 2009 and U.S. Patent Application No. 61/382,905 to Valencia filed Sep. 14, 2010, now pending, each of which is incorporated by reference herein in their entireties.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0003] Not Applicable.
FIELD
[0004] Embodiments of the claimed subject matter relate to devices, systems and methods using those devices used in training animals, and more particularly, devices that can be attached or used in conjunction with collars providing one or more alerts for eliciting and enhancing the responsiveness of the animal.
BACKGROUND
[0005] It is well know that many devices have been disclosed in the prior art that assist in training and enhance the responsiveness of animals. Of particular interest are training devices which are worn by animals.
[0006] For example, U.S. Pat. No. 6,748,902 (issued to Boesch et al.) discloses an animal worn training device that attaches to a lead having a transducer that responds to the amount of force pulling on the leash. If the force from pulling exceeds a first threshold a warning audio tone sounds and if the force from pulling strength exceeds a second threshold level, then a shock is administered to the animal.
[0007] United States Published Application No. 2007/0261645 to Van De Merwe et al. discloses a pet leash apparatus that deters a dog from pulling on the leash. The focus of this disclosure is towards spray to control the animal. Ultrasound emissions and electrical shocks are also disclosed though the main focus remains on spraying the animal.
[0008] U.S. Pat. No. 6,116,192 to Hultine et al. describes an animal training device which is a electric pulse generator attached between the collar and leash that is used to shock as animal. The disclosed device has cylindrical, sliding inner and outer housings.
[0009] Patent Number DE 20313319 to Flexi Bogdahn Tech relates to an animal control device with a cable 30 wound on a reel, a battery and a sensor used to activate a loudspeaker via a metal clamp near the end of the lead. As the metal clamp approaches the sensor, a signal is emitted that can be recognized by the animal.
[0010] United States Published Patent Application No. 2008/0173257 to Steiner et al. describes a retractable animal leash and methods for animal control. The apparatus can be configured to generate unpleasant high-sonic or ultrasonic (e.g., greater than 20 kHz) emissions akin to a dog whistle.
[0011] To the best of the inventors' knowledge, the present embodiments of such improved devices and methods have not been provided in the art. The present application provides some of such improved methods and devices that are useful in the training of animals.
SUMMARY
[0012] According to one aspect of the invention, there is provided an activation device for an ultrasonic transducer which is capable of producing sound waves having one or more predetermined or user adjustable decibel level and one or more predetermined or user adjustable frequencies. The activation device is coupled to a circuit that is used to produce sound waves. A battery supply can provide electrical power for circuits and the transducer.
[0013] Embodiments described herein detail devices and methods that are useful in the training of animals, specifically dogs. These embodiments employ devices that provide an alert for an animal to enhance the responsiveness of the animal. In one embodiment, sound waves having a sufficiently high frequency to be inaudible to humans but audible to many animals, such as dogs, are employed to provide an alert.
[0014] In another embodiment, the sound level produced, as measured in decibels, can be altered for different training purposes. For example, one sound wave may be produced to elicit one desired behavior or two or more different sound waves can be used to elicit desired behaviors in the animal.
[0015] In another embodiment, a circuit board is configured with a circuit can be used to regulate the production of sound. The circuit board has inputs to receive signals from an activation mechanism. The activation mechanism produces signals upon the occurrence of an event, for example, movement in a mechanical device, which can be used to trigger the activation mechanism. The switches, or other activation device, can be configured to produce different volumes of sound.
[0016] In another embodiment an indicator light activates if the device is producing sound waves to enable humans to understand the events as they occur. In another embodiment, two casing layers are used to house the unit and movements of the two casing relative to each other causes the sounds waves to be produced.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] FIG. 1 is an illustration of an embodiment of an activation device;
[0018] FIG. 2 is an illustration of the embodiment of FIG. 1 showing motion activation;
[0019] FIG. 3 is an illustration of the embodiment of FIG. 1 showing the inner casing;
[0020] FIG. 4 is an illustration of the embodiment of FIG. 1 showing the outer casing;
[0021] FIG. 5 is an illustration of an embodiment for electronics that can be used with the activation device shown of FIG. 1 ; and
[0022] FIG. 6 is an embodiment of a circuit diagram for controlling an ultrasonic transducer.
[0023] FIG. 7 is an illustration of another embodiment of the inventive subject matter;
[0024] FIG. 8 is an illustration of the embodiment of FIG. 7 with a clip attachment positioned at the rear of the embodiment;
[0025] FIG. 9 is an illustration of the embodiment of FIG. 7 shown from the top with a clip attachment positioned at the rear of the embodiment;
[0026] FIGS. 10A and 10B are illustrations of several components an embodiment of FIG. 7 with a clip attachment positioned at the rear of the embodiment;
[0027] FIG. 11 is an illustration of the embodiment of FIG. 7 showing the use with an external 9 Volt battery supply;
[0028] FIG. 12 shows a breakaway view of a PCB with side walls according to an embodiment of the subject matter;
[0029] FIG. 13 shows a breakaway view of a PCB without side walls according to an embodiment of the subject matter;
[0030] FIG. 14 shows additional housing configurations used with embodiment of the subject matter;
[0031] FIG. 15 shows a breakaway view of a PCB without side walls according to an embodiment of the subject matter;
[0032] FIG. 16 is an illustration of several components of an embodiment including a channel for a slideable line, cord or rope which may be used with embodiments of the subject matter; and
[0033] FIG. 17 shows a housing configuration used with an embodiment of the subject matter.
DETAILED DESCRIPTION
[0034] Referring first to FIG. 1 , an illustration for an embodiment of an activation device 10 is shown which is constructed using an outer casing 21 and an inner casing 22 that are slideably engaged with each other such that inner casing 22 can slide in to and out of, of outer casing 22 . Activation device 10 has first attachment mechanism 11 for attachment to an animal collar and second attachment mechanism 12 used for attachment to a leash for a dog or other type of animal. Audio device 15 provides an alert once collar 10 is stretched beyond a certain point. The outer casing 21 to activation device 10 has cut out area 18 a and protrusion area 19 a that allow for accommodation of levers 18 , 19 . Levers 18 , 19 are contained on inner casing 22 and used to activate the alert generated by audio device 15 . Inner casing 22 is slideably mounted with respect to outer casing 21 .
[0035] A pulling force exerted on activation device 10 while attached to an animal will force outer casing 21 to slide with respect to inner casing 22 effectively elongating collar 10 . As the outer casing 21 slides over outer casing 22 , protrusion area 19 a no longer abuts lever 19 . Instead an area of outer casing 21 without any cut out or protrusion areas abuts lever 19 causing a depression of lever 19 . The depression of lever 19 causes an ultrasonic alert sound to be made by audible device 15 . The activation device 10 can be used for training of animals, including dogs, horses. Activation device can provide an alert useful in training an animal and enhance the responsiveness of the animal.
[0036] It should be understood that levers 18 , 19 are just one possible mechanism that can be used within the embodiment shown in FIG. 1 to activate the alert. Other mechanisms can be used in varying embodiment that can detect to the mechanical movements are also envisioned. Optical detectors could be used in place of levers 18 , 19 . In FIG. 1 , lever 19 is shown as a dotted line because it is contained below outer casing 21 . Lever 18 is shown as solid lines because area 18 a is actually a cut out in outer casing 21 . It should be understood that cut out area 18 a and protrusion area 19 a are simply examples contained in a single embodiment and that numerous variations are envisioned.
[0037] Referring to FIG. 2 , which is an illustration of the activation device 10 sliding as a result of pulling by an animal on a leash connected to attachment mechanism 12 causing the outer casing 21 to slide with respect to inner casing 22 . It should be noted that first attachment mechanism 11 and second attachment mechanism 12 would normally be attached to each other during use and that a dog leash (not shown) would attach to one of the either the first attachment mechanism 11 or second attachment mechanism 12 . In FIG. 2 , the protrusion 19 a in the outer casing 21 has slid past both levers 18 and 19 . As a result, both levers 18 and 19 are beneath outer casing 21 are shown in dotted lines. The sliding of outer casing 21 over lever 19 causes a first audible alert to be sounded by audio device 15 . Once outer casing 21 slides over lever 18 , a second audible alert is sounded.
[0038] Various embodiments are envisioned here. For example, the first and second audible alerts can be the same frequency and decibel level; different frequencies having the same or similar decibel levels; or the same frequencies with different decibels levels. Additional embodiments are envisioned that will have continuous alerts sounding, alerts that are a series of beeps or simply a single sound made be the depression of each of levers 18 and 19 .
[0039] An embodiment will have audible device 15 create sound waves that have a sufficiently high frequency to be inaudible to humans but audible to many animals, such as dogs, are employed to provide an alert. In another embodiment, the sound level produced, or decibels, can be altered for different training purposes. The sound waves can be triggered to mandate desired behaviors in the animal.
[0040] FIG. 3 shows the outside of the inner casing 22 with the outer casing 21 removed. Levers 18 , 19 as well as audio device 15 , attachment mechanism 12 and spring 33 are connected to inner casing 22 . Spring 33 provides a biasing force that keeps activation device 10 in the original state shown in FIG. 1 . The biasing can alternatively be provided by elastomeric materials or any type of device that will provide a biasing force. FIG. 4 shows the outer casing 21 with a clip for attaching to a collar as attachment device 11 . Aperture 25 is formed in outer casing 21 to allow audio device 15 to have access to the ambient surroundings to be heard.
[0041] FIG. 5 is a diagram of the internal layout to inner casing 22 . An ultrasonic transducer can be used as audio device 15 to produce the sound waves having a predetermined decibel level and a predetermined frequency. Circuit board 51 rests inside of inner casing 22 with switches 31 , 32 that are activated by levers 33 , 34 , respectively. Circuit board 51 contains the circuits that control that production of signals to have ultrasonic transducer used as audio device 15 produce sound waves. Modernly, circuits can be miniaturized to produce the desired sound waves or an analog circuit can be used to produce the sound waves. Devices can be coupled to the circuit used to produce sound waves. Various mechanisms are envisioned as possible alternatives to activation devices. Switches, optical or other activation devices, can be configured to produce different volumes of sound. A battery supply can provide electrical power for circuits and the transducer.
[0042] In an embodiment, circuit board 51 is configured with a circuit to regulate the production of sound. The circuit board 51 can have an input or a set of inputs to receive signals from switches or other mechanisms used for activation. The signals are activated upon the occurrence of an event, for example, movement in a mechanical device, which can be used to trigger the activation mechanism. Once triggered by the signal, the activation device 10 will produce ultrasonic sounds. Switches 32 , 33 are attached to the circuit board 51 and can be used to activate the ultrasonic sound. The switches 32 , 33 , or other activation device, can be configured to produce different volumes of sound. A battery supply 52 can be used to provide electrical power for the circuit board 51 and transducer 15 . In an embodiment switch 38 provides for selectively changing frequency. In another embodiment switch 30 provides for a selection of small or large for the animal type with more sliding of inner and outing casings in 21 , 22 for a larger animal.
[0043] FIG. 6 is an example of a circuit that can be placed on circuit board 51 . The circuit of FIG. 6 can be used to create the different frequencies. [Did you have another example of a circuit?] A sinusoidal wave is created from a 9 volt D.C. input. Included in FIG. 6 is a simple inverter oscillator which uses an R/C feedback circuit in which the resistor (R) and the capacitor (C) values are calculated to produce 25 Khz. Input 61 is the input from switch 31 and input 62 is the input from switch 32 in FIG. 5 . In an embodiment, an indicator light 63 is provided to illuminate when the activation device 10 is producing ultra sonic sound waves to enable the human operator to understand the events as they occur. The circuit of FIG. 6 has ultrasonic transducer PZ 1 that receives inputs from transformer T 1 . Transformer T 1 receives inputs from two mirror transistor circuits. Transformer T 1 has a 1:2 ratio. Therefore, application of a 9 volt p-p sine wave to the input of transformer T 1 will result in twice that amount out of transformer T 1 , e.g. 18 volts. Labels 66 , 67 , and 68 are supply voltages the come from the switches 1 , 2 . R 3 can control the frequency value has it is adjusted. L 1 indicates inputs from switches 1 , 2 . R 5 receives the input from switch 1 , R 10 receives the input from switch 2 . The switches 1 , 2 apply the power from battery 52 to R 5 , R 10 , respectively. R 5 is 0 ohms for full power or maximum loudness. R 10 can be selected to reduce volume output.
[0044] In an embodiment, a unit comprising the ultrasonic transducer 15 , circuit board 51 , and activation switches mechanism are incorporated two casing layers. Two casing layers are used to house the unit. The inner casing layer houses all electrical components. The ultrasonic transducer is attached to the inner casing in a way that it protrudes from the casing layer. The inner casing layer has multiple levers that can be pressed down into the casing layer. These levers operate the switches described earlier. The outer area of the inner casing layer must be in a cylindrical shape in order to accommodate the spring mechanism. A spring is placed around the cylindrical part of the casing and the outer casing layer is then attached. The spring can vary in strength and size to obtain a wide range of applications. At one end of the inner casing layer an attachment device, such as a clip, is attached.
[0045] The outer casing layer is slightly larger than the inner casing. The inner area of the outer casing layer can be cylindrically fashion in a particular embodiment. The outer casing will cover the inner casing entirely with the exception of one of the switches. The other switch(es) will be covered with a hood that protrudes from the outer casing layer. The hood will be elevated over the switch(es). At one end of the outer casing layer an attachment device, such as a clip, is attached. The end used must be the opposite side from the inner casing attachment device.
[0046] The device operates in multiple ways. One being to keep an animal from pulling on a leash. The device can be attached to the animal's collar, harness, or similar apparatus via the attachment device on the casing layer. The other attachment device on the other casing layer is attached to the leash. When the animal pulls forward the outer casing layer is extended outwards and the spring mechanism retracts. When the animal is not pulling and there is no pressure applied, the spring pressure retracts the outer casing layer back over the inner casing layer and the spring is back in its original position.
[0047] When the outer casing layer is extended it moves forward depressing the levers on the inner casing layer in an ordered fashion. The first lever depressed activates a switch which activates an ultrasonic sound. As the outer casing continues to extend outwards, the next switch(es) are depressed. The lever(s) produce(s) an ultrasonic noise that is higher than the volume(s) produced by the preceding lever(s).
[0048] The device can be used manually without attachment to the animal. A person can hold the device freely and operate the lever(s) on the inner casing layer that are not covered by the outer casing. This can be used for behavior modification in an animal.
[0049] Other embodiments may be used with clips, harnesses, collars as well as any other restraining device. The embodiments may be used with any suitable animal including dogs, cats, horses, and any other animal that can hear the designated frequency such as ranges in the 20 kHz to 30 kHz or any other suitable range. The described embodiments may also be used with a leash, rope, chain or any other suitable restraining element which is attached at one end to a stationary object, a person such as a walker of the animal or any other element which can substantially secure the embodiment and the attached animal so that the animal remains in proximity to the embodiment.
[0050] FIG. 7 is an illustration of another embodiment of the inventive subject matter showing the aperture in which a line may be used to hold an animal. In this embodiment, when the animal attached to the device pulls away from the device a spring is compressed by a rod that is compressed/extended out of the device by the pulling action. When the rod reaches a predetermined activation point on the PCB, an frequency wave or waves are activated and emitted and the noise/signal emitted by the device is heard by the animal. When the animal stops pulling, the spring tension pulls the device back into the device which signals the PCB to deactivate the frequency wave or waves so that the noise emitted from the device stops.
[0051] In several embodiments, a manual mode is provided to the animal does not need to pull the device in order for it to emit a noise. In these embodiments, a user can manually activate the production or cessation of the noise with or without action by the animal connected to the device. In several of the embodiments, the level of noise can be adjusted manually by the user or it may be adjusted automatically by the PCB, for instance in relation to the distance the animal is from the device. This information may be gathered from any suitable distance reading device known to those skilled in the art.
[0052] FIG. 8 is an illustration of the embodiment of FIG. 7 with a clip attachment positioned at the rear of the embodiment. The clip could then be attached to a lead line which is in turn attached to an animal that can pull forward, pull back or not move in relation to the embodiment.
[0053] FIG. 9 is an illustration of the embodiment of FIG. 7 shown from the top with a clip attachment positioned at the rear of the embodiment and the slideable mechanism with spring attached to the clip. The PCB assembly is shown under the slideable mechanism and spring.
[0054] FIGS. 10A and 10B are illustrations of several components an embodiment of FIG. 7 with a clip attachment positioned at the rear of the embodiment. FIG. 10A shows the spring in an extended position and FIG. 10B shows the spring in a compressed position.
[0055] FIG. 11 is an illustration of the embodiment of FIG. 7 showing the use of the embodiment with an external 9 Volt battery supply and FIG. 12 shows a breakaway view of a PCB with side walls according to an embodiment of the subject matter. FIG. 13 shows a breakaway view of an embodiment with a PCB without side walls and FIG. 14 shows additional housing configurations used with embodiment of the subject matter.
[0056] Another embodiment includes a frequency changing switch which can also lower the frequency to the audible range for humans. Additional embodiments may emit both ultrasonic frequencies and frequencies audible by humans. In several of these embodiments, a user may select one or both of these functions so that the emitter emits one or more than one frequencies when the emitter is activated by the apparatus 10 .
[0057] In other embodiments, an additional speaker may be used with the apparatus 10 , for example a mini loud speaker or other audible frequency generator known to those skilled in the art. In several of these embodiments, the additional audible frequency generator may be used in conjunction with the ultrasound generator, for example to have more than one reinforcement sound provided to the animal for more effective training results. The one or more additional sounds which are audible to humans also provide a signal that lets the person know when the animal is pulling. This will not only increase the effectiveness of the animal training, but also aid in the understanding of the results of the training by the person using the apparatus or third parties observing the use of the apparatus 10 . For example, a person training a dog can know when the dog is pulling via this alarm and can take the corrective action such as a tug back, a command to stop walking, or a verbal command to heal. This would reinforce the audible sounds received by the dog. In other embodiments, the apparatus 10 may use an additional audible frequency generator to emit before the ultrasound is emitted to aid in training the dog to stop pulling prior to the ultrasound going off, and to allow the trainer to take corrective measures before the ultrasound is emitted.
[0058] In several embodiments, a light such as an ultra-bright light LED or light emitting diode can be attached to the device to activate in the same manner as the audible loud speaker. This light can give the dog additional corrective stimuli to train the animal which would aid the sound generated to more effectively train the animal. The embodiments may also be used as a personal safety device for the animal, the trainer and/or third parties. For example, one or more loud speakers can be used to ward off attacks and draw attention to an emergency situation. Additionally, a light such as an ultra bright light LED may be used for night and low light conditions to aid in visibility.
[0059] In other embodiments, the apparatus 10 further includes a shut off safety timer. In these embodiments, the apparatus could be set to shut off at a certain point. For example, this element would shut the sounds off if a dog was left unattended and the sounds were to be continuously emitted, for instance in a situation such as when the dog was caught up on the device or wrapped in its leash which would make the apparatus emit sound continuously.
[0060] In many embodiments, a spring is used with the apparatus 10 but any suitable elastic material or other material with spring like properties may be used. Similarly, in many of the embodiments, a limit switch is used to actuate or trigger the emitted but other elements such as proximity/reed switch with a magnet may also be used in conjunction with or instead of the limit switch. Other embodiments may use a contract break instead of the closing a contact point. For example, two contacts that connect on the same pull mechanism may be used. In these embodiments, if the housing where to break, the unit would still work. In these embodiments, the two contacts may be positioned on the same plane with the wire leads wrapped around to ensure the device will continue to work should the housing break.
[0061] In several of the embodiments, a metal or polymer pull mechanism may be used to attach the leash to the collar. In these as well as other embodiments, the apparatus 10 may be used with any animal restraining device including but not limited to collars, harnesses, muzzles.
[0062] In many of the embodiments, the frequency emitted may be changed by the user or the apparatus may be made to send out different frequencies. For example, a user may use the limit switch so that the apparatus 10 emits more than one frequency and these frequencies may be used to train more than one animal simultaneously.
[0063] In several of the embodiments, the apparatus 10 uses a clip (such as a swivel clip positioned at the rear of the housing) and this clip may be used in order to allow the leash to be looped around the animal's neck and threaded through the clip. In these embodiments, a separate collar would not be needed as the leash (formed as a loop) would function as a collar.
[0064] In several of the embodiments, a LED indicator light may be used to indicate if there is a sufficient voltage to drive the piezo. For example a zener diode, additional diodes, and a resistor may be used. A light may also be used to indicate a low battery or a malfunction of the PCB board controller. For example, a led indicator can be used by splitting up the positive and negative pulses and running battery checks on both currents. If the currents are not identical, the light could emit indicating a potential malfunction with the board.
[0065] In several of the embodiments, the apparatus 10 may 3 coin lithium batteries as a power source. In other embodiments, rechargeable batteries may be used with the apparatus 10 and those batteries could be plugged into an external power source and periodically recharged.
[0066] Although the foregoing embodiments of the inventive subject matter have been described in some detail by way of illustration and example for purposes of clarity and understanding, it will be apparent to those of ordinary skill in the art in light of the teaching of this invention that certain changes and modifications may be made thereto without departing from the spirit or scope of the inventive subject matter including the appended claims. | Embodiments of the claimed subject matter relate to devices, systems and methods using those devices used in training animals, and more particularly, devices that can be attached or used in conjunction with collars and/or leashes with provide one or more alerts for eliciting and enhancing the responsiveness of the animal. One example device for training animals includes a housing with a connector for a leash, a noise emitter capable of producing one or more noises with one or more ranges of frequencies, a circuit that signals the audio device to provide or stop the one or more noises and a switch to activate the circuit. The circuit is activated when the leash is pulled with a predetermined amount of force and the circuit activates the noise emitter which produces one or more noises. The circuit is deactivated when the leash is released and the noise emitter stops emitting noise. | 0 |
[0001] This invention relates generally to canal and levee devices, and specifically to structural reinforcement of canal and levee devices.
STATEMENT REGARDING FEDERALLY FUNDED RESEARCH
[0002] This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.
BACKGROUND OF THE INVENTION
[0003] The strength and durability of canals and levees in the US has never been more important than at the present time, as the continual physical development of the nation brings ever larger numbers of individuals and ever more expensive physical investments into areas prone to damage should a levee or canal break.
[0004] Obviously, the devastation in the aftermath of Hurricane Katrina and the collapse of the levees protecting New Orleans and other parts of Southern Louisiana from flooding of the waters of Lake Pontchartrain is the first example of this which comes to mind: at least 1836 people lost their lives. It has been estimated that if the federal government undertook the task of rebuilding New Orleans, it would cost between 80 and 100 billion US dollars.
[0005] But the problem is potentially much more widespread than that. There are so many aqueducts, ditches, canals and levees in the United States that numbering them may be impossible.
[0006] The single largest and most expensive aqueduct system built in the US, the Central Arizona Project, has a backbone which covers 336 miles (˜540 km) from Lake Havasu to the Tucson area, with vast amounts of concrete and berming used to try and provide long term stability to the walls of the aqueduct.
[0007] Numerous other smaller US canals and aqueducts exist, for example, the California Aqueduct is 444 miles (˜700 km) long. One (partial) list of US irrigation aqueducts includes the All-American Canal, Coachella Canal, the Colorado River Aqueduct, the Contra Costa Canal, the Hillsboro Canal, the Los Angeles Aqueduct and storm drainage system often seen in movies, the Miami Canal, the famous St. Lucie Canal crossing Florida, the Tamiami Canal, the El Paso Canal, the Franklin Canal, the American Canal, the largely abandoned Erie Canal, and the Riverside Canal, however, many more irrigation canals exist, and a large number of transportation canals also exist as well. Most of these are “dug in” and thus not in immediate danger of collapse, but nonetheless large numbers of levees and canals have miles of unsupported “levee” style sides. The Army Corps of Engineers inspects over 2,000 levees nationwide, some of them miles long. The total number of levees in the US may be unknown, but the Corps estimates that up to 146 of these levees may present flood risks in danger of failure. In the end, many of these levees and many more will need to be made stronger.
[0008] Thus even if irrigation ditches and the like (functionally smaller canals and smaller levees) are not counted, the problem of levee strength is a gigantic one.
[0009] It would be preferable to provide some method of increasing the strength of levee walls at low cost, without berming or other large scale engineering projects.
[0010] Various systems exist of internal bracing.
[0011] U.S. Pat. No. 4,596,491 to Dietzler on Jun. 24 th , 1986 teaches small bore plastic pipes having internal reinforcement, and since it involves small pipes, it cannot be considered relevant to levees large enough to hold supertanker ships. The internal reinforcement is primarily designed to withstand external forces rather than hydrostatic or hydrodynamic forces.
[0012] U.S. Pat. No. 6,202,305 to Bracque et al on Mar. 20 th , 2001 teaches a large air distillation column with external bracing around a cylindrical central fluid unit, which suffers from a great structural variance from both prior art levees and also from the present invention.
[0013] U.S. Pat. No. 4,315,099 issued to Gerardot et al on Feb. 9 th , 1982 teaches yet another pipe or cable type device, again not relevant to ocean or river levees.
[0014] Finally WO 2004/056677 to Ki-jun Kim and published Jul. 8 th , 2004, teaches a portable cubical holding tank with internal supports which run in diagonal directions between small square plates of the skin of the tank. It does not teach a design allowing waterborne traffic, does not teach perpendicular internal supports and relates to water storage, not to waterways or shorelines.
SUMMARY OF THE INVENTION
[0015] General Summary
[0016] The present invention teaches that a levee, canal or aqueduct wall may be internally supported by tensional members such as cables, bars, chains, carbon composites and the like which stretch across the width of the waterway. By this means, outward hydrostatic and/or hydrodynamic force of water onto the wall of the waterway or shoreline levee is matched by a tensional force anchored on the opposite wall.
[0017] In embodiments the tensional members may leave a space between the topmost member and the water level, so as to allow for passage of water vessels above the cables, in waterways, lakes or oceans in which traffic occurs.
[0018] Vertical or horizontal struts or individual anchors attached to the ends of the cables may be positioned within, partially within or outside of the walls. Struts may extend so as to provide anchoring to several tensional members, and in addition act to spread the tensional forces of the member onto a larger area of the wall.
[0019] Due to the strength of the device, the waterway wall/shoreline levee may even be constructed at an angle to the vertical, even leaning outwards, advantageous in that it allows a wider waterway for traffic but may be narrower at the bottom as necessary for local conditions.
[0020] External guying tensional members may be anchored and may connect to the wall or the internal tensional members to provide tensional support to prevent motion in the inward direction, especially collapse, either temporarily (such as during construction) or permanently. These anchoring guying tensional members would also provide stability in situations where hydrostatic and/or hydrodynamic pressure may be greater on one of the 2 walls or the waterway, such as a curve or change in course of the waterway.
[0021] Unlike tensional members for placid water storage devices, such as water tanks, the tensional members of the waterways of the invention must be anchored, strong enough, and dimensioned and configured to resist the side pressure of moving water.
[0022] Summary in Reference to Claims
[0023] It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a waterway comprising:
[0024] first and second parallel facing sidewalls having a first thickness, two proximally open sides and a bottom, thereby defining therebetween an extended longitudinal water course through which water may flow for a first distance;
[0025] at least one tensional member firmly secured to and bearing load in tension from both sidewalls.
[0026] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0027] two ends of the tensional member; and
[0028] at least one anchor firmly securing at least one end of the tensional member to at least one sidewall.
[0029] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, wherein the tensional member further comprises:
[0030] a cable.
[0031] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0032] a second tensional member firmly secured to and bearing load in tension from both sidewalls at a second distance from the first tensional member.
[0033] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
a vertical navigation clearance distance, the vertical navigation clearance distance greater than the second distance.
[0035] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0036] two ends of the perpendicular tensional member; and
[0037] at least one horizontal anchor strut firmly securing at least one end of the tensional member to at least one sidewall.
[0038] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0039] two ends of the perpendicular tensional member; and
[0040] at least one vertical anchor strut firmly securing at least one end of the tensional member to at least one sidewall.
[0041] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0042] at least one guying tensional member external to the water course, the at least one guying tensional member having a first end secured to the first wall.
[0043] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0044] a second end of the at least one guying tensional member, the second end secured to an anchor located separate from the first wall.
[0045] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway, further comprising:
[0046] two ends of the tensional member; and
[0047] at least one anchor firmly securing at least one end of the tensional member to at least one sidewall, the anchor having a U-shaped body, the U-shaped body having an internal diameter, the internal diameter substantially equal to the first thickness.
[0048] It is therefore another aspect, advantage, objective and embodiment of the invention to provide a waterway wherein the second distance between the first and second tensional members further comprises:
[0049] an intermediate navigation clearance distance.
BRIEF DESCRIPTION OF THE DRAWINGS
[0050] FIG. 1 is a cross-sectional view of a first embodiment of the device showing a simple embodiment.
[0051] FIG. 2 is a cross-sectional diagram of a second embodiment of the device, having a space allowing navigation above the tensional members.
[0052] FIG. 3 is a cross-sectional diagram of a third embodiment of the device, showing vertical outside struts.
[0053] FIG. 4 is a cross-sectional diagram of a fourth embodiment of the device showing horizontal longitudinal outside struts.
[0054] FIG. 5 is a cross-sectional diagram of a fifth embodiment of the invention showing that it makes it more practical to make levees or canals with sides sloping outward but without earthen or other support.
[0055] FIG. 6 is a cross-sectional diagram of a sixth embodiment of the invention showing that external guying tensional members may be used.
[0056] FIG. 7 is a cross-sectional diagram of a seventh embodiment of the invention showing that tensioning members and walls of the levees may extend into and under the ground beneath the waterway.
[0057] FIG. 8 is a cross-sectional diagram of an eighth embodiment of the invention showing that elevated guying tensional members may be used.
[0058] FIG. 9 is a cross-sectional diagram of a ninth embodiment of the invention showing that a sleeved retrofit may be used within the scope of the invention.
[0059] FIG. 10 is a top planform view of a section of waterway seen from above, showing alternative arrangements of the tensional members.
[0060] FIG. 11 is a cross-sectional diagram of an tenth embodiment of the invention showing that only elevated guying tensional members may be used.
[0000]
INDEX TO REFERENCE NUMERALS
Levee/canal
100
First side wall
102
Second side wall
104
Open bottom
106
Foundation/berm
108
Tensional members
110a-i
Tensional tightening mechanism
111a, 111b
Bottom
206
Tensional members
210a-d
Vertical navigation clearance
212
First side wall
302
Second side wall
304
Open bottom
306
Foundation/berm
308
Tensional member
310a
Vertical strut
312
Tensional members
410a-d
Horizontal longitudinal struts
416a-d
First eccentric side wall
502
Second eccentric side wall
504
Differing tensional members
510a-d
Side wall
604
Tensional members
610a-d
Guying tensional members
618a-d
Anchor
620
First sidewall
702
Second sidewall
704
Berm
708
First tensional member
710a
First sidewall
802
Tensional member
810d
Sidewall
902
Tensional member
910d
Sleeve
922
Opening/attachment
924
Sidewall
1004
First tensional member
1010d
Second tensional member
1026
Third tensional member
1028
Anchor
1030
First sidewall
1102
Tensional member
1110d
DETAILED DESCRIPTION
[0061] FIG. 1 is a cross-sectional view of a first embodiment of the device showing a simple embodiment. Levee/canal 100 may be a small “ditch” (irrigation canal mere inches or feet in width) or it may be wide enough to allow supertanker ships. In any case, it may extend for a first distance which may be as much as many miles in length or it may be merely blocks in length, as some of the levees are in the city of New Orleans.
[0062] First side wall 102 and second side wall 104 act to contain water within the confines of the waterway. The side walls 102 , 104 may be constructed of reinforced concrete, concrete, metal, masonry, carbon composites, wood, and combinations thereof and have a first thickness suitable to containing such water given the additional reinforcement provided by the invention. In particular, in original equipment installations, the thickness of the walls may be less than the thickness of a side wall required to withstand the hydrostatic and hydrodynamic forces of the waterway unaided. The side walls 102 , 104 may have foundations, or may have small earthen berms 108 as foundations as shown, or may sit atop substantial berms for additional height, or may realistically extend into the ground for a certain depth, so as to act as their own foundations.
[0063] Open bottom 106 may exist in certain embodiments such as irrigation channels or the like.
[0064] Side walls 102 , 104 and bottom 106 define therebetween the extended/elongated water course of the waterway, through which water may flow from end to end of the waterway for the distance of the waterway, as two locally or proximally open “sides” of the waterway allow the waterway to be a waterway for moving water or vehicular traffic rather than a storage tank having four enclosed sides. That is, the device of the invention has two side walls and two openings (the entire length of the waterway) which allow water flow therethrough. The total length of the waterway may have one or two “ends” at some distant location, but is nonetheless locally open on two sides at any point other than the end or ends and thus the proximal sides are “open” for the entire intermediate length of the waterway so as to allow motion of water or ships through the waterway.
[0065] Foundation/berm 108 may be constructed of rammed earth or the like, or may be constructed of concrete or the like.
[0066] Tensional members 110 a - i may be present in such numbers are as necessary to support the expected maximum load of water. In embodiments, at least one perpendicular tensional member is used, secured to each facing sidewall and extending across the width of the waterway between the sidewalls under tension, so as to provide tensional support to each wall and in effect, to “balance” the forces generated by water on one wall with the forces generated by water on the other wall. A first distance may separate two of the tensional members, which distance may be vertical or horizontal or a combination of both, and which distance may be different for different pairs of the members.
[0067] Preferably the tensional members should be perpendicular to the length of the parallel side walls, as non-perpendicular tensional members will exert undesirable forces along the length of the side walls. However, in alternative embodiments other orientations may be used.
[0068] Unlike tensional members for water storage devices with little or no water motion, the tensional members of the waterways of the invention must undergo lateral forces due to moving water (hydrodynamic forces) and thus are structurally more sturdy than tensional members for static water structures: this difference is termed “strong enough to resist lateral hydrodynamic forces” for purposes of this invention. The tensional member of the invention must also have stronger anchoring, and must dimensioned and configured to resist the side pressure of moving water. For example, the tensional members may have struts or anchors as discussed in regard to FIG. 3 and other figures, and must be anchored into the strong, normally reinforced concrete walls of the waterway. The tensional members may also have hydrofoil cross shapes to aid in minimizing forces due to water flow or water motions (such as from passing vessels). Tensional tightening mechanisms 111 a , 111 b may be provided to maintain the tensional members under tension at all times or to tighten them as necessary periodically. It will be appreciated that unlike static water holding tanks, random variations in moving water of waterways will cause random variations in tension, which may be undesirable, and thus tightening mechanisms may be necessary.
[0069] It may be seen that the device and apparatus of the invention may easily be retrofitted to an existing waterway wall or incorporated as original equipment in a newly constructed/reconstructed wall. In particular, the use of struts/anchors external to the wall is suited to retrofit applications.
[0070] The device of the invention even allows creation of portable temporary waterways, since the waterway of the invention can be constructed with no berming nor concrete of any type, merely with large strong plates or panels joined at water-tight edges so as to make walls, with cables to support the walls.
[0071] While the top of waterway is shown to be open, the waterway may of course be enclosed in alternative embodiments of the invention.
[0072] FIG. 2 is a cross-sectional diagram of a second embodiment of the device, having a space allowing navigation above the tensional members.
[0073] Bottom 206 may be a solid construction, much like the side walls. For example, the bottom 206 may be reinforced concrete or other materials used in the construction of the side wall, including portable panels.
[0074] Tensional members 210 a - d may be seen to be disposed with a fairly large vertical navigation clearance 212 between them and the maximum water level in the waterway. In the diagram, the tensional members 210 a - d may be seen to be disposed closer to bottom 206 than to the top of the waterway side walls and/or the maximum water level (which may be either below the top of the waterway side walls or coterminous therewith).
[0075] FIG. 3 shows water traffic using such a waterway, as long as the depth of water above the topmost tensional member exceeds the draft of the vessels using the waterway.
[0076] FIG. 3 is also a cross-sectional diagram of a third embodiment of the device, showing vertical outside struts. First side wall 302 and second side wall 304 bear on them anchors which aid in securing the tensional members such as tensional member 310 a to the side walls 302 , 304 . The wall anchors also aid in transferring the load from a larger area of the wall to the tensional members, thus providing load distribution and allowing for thinner and thus more portable walls.
[0077] Vertical strut 312 may be seen to be one such anchor, which in this variant embodiment extends vertically up the sides of the waterway walls. Such anchors may be disposed on the outside faces of the walls, or may be partially within the wall structure, or may even be entirely within the wall structure. Each strut 312 may meet more than one tensional member in a vertical direction.
[0078] Open bottom 306 and foundation/berm 308 are as previously discussed in relation to FIGS. 1 and 2 .
[0079] FIG. 4 is a cross-sectional diagram of a fourth embodiment of the device showing horizontal longitudinal outside struts, the preferred embodiment and best mode contemplated for the invention.
[0080] Tensional members 410 a - d meet a plurality of horizontal longitudinal struts 416 a - d , which may extend along the length of the waterway (or at least a portion of the waterway length) or may be individual cable end anchors anchoring only one tensional member end. If the longitudinal struts are employed, then each strut may secure a number, even a large number, of cables disposed in a horizontal line.
[0081] Note that in alternative embodiments, struts may extend in a diagonal direction and meet and secure several cable ends.
[0082] FIG. 5 is a cross-sectional diagram of a fifth embodiment of the invention showing that the invention makes it more practical to make levees or canals with sides sloping outward but without earthen or other support. First eccentric side wall 502 and second eccentric side wall 504 may extend in directions not necessarily vertical, nor even mirror images of each other, if properly supported by differing tensional members 510 a - d , which may be seen to have differing lengths. Normally extensive berming is required to make an aqueduct or canal or levee wall safe in a non-vertical orientation, however, the present invention allows quick construction of a waterway even with sloping side walls 502 and/or 504 . Advantages of such slopes include the ability to allow the waterway to avoid ground level obstacles, allow creation of a smaller bottom and/or smaller “footprint”, and yet allow a wider waterway for increased water flow or wider waterborne traffic.
[0083] FIG. 6 is a cross-sectional diagram of a sixth embodiment of the invention showing that external guying tensional members may be used. Side wall 604 has internal tensional members 610 a - d and also has another set of secure attachments to guying tensional members 618 a - d which are located external to the waterway. The secure attachments of the internal and external tensional members may be at the same place, functionally connecting the two sets of members, or the attachments may be at different places, or there may be single set of tensional members which extend through the side walls and are thus both external and internal to the waterway, and are also both external and internal to the side wall 604 .
[0084] Anchor 620 may be of normal type for suspension cable anchoring, devices of the type are used in suspension bridge construction and similar applications.
[0085] The width, size, length and material of the members may be different between external and internal or between members located at different locations, as seen in comparing the lower and upper external tensional members 618 a and 618 d of FIG. 6 .
[0086] FIG. 7 is a cross-sectional diagram of a seventh embodiment of the invention showing that tensioning members and walls of the levees may extend into and under the ground beneath the waterway. First sidewall 702 and second sidewall 704 may be seen to extend their feet or foundations down into or even through and below berm 708 . First tensional member 710 a may be seen to be partially or wholly underground in such variations.
[0087] FIG. 8 is a cross-sectional diagram of an eighth embodiment of the invention showing that elevated guying tensional members may be used. An intermediate navigation clearance distance is thus created allowing vehicular traffic to pass below some sets of cables, and also decreasing the water flow drag on the cables by reducing the number of cables underwater.
[0088] First sidewall 802 may be seen to be tall enough to allow tensional member 810 d to extend therefrom yet still be above the level of waterborne traffic. Posts, pillars and extensions of the sidewall and the like may be used to elevate the tensional members in variations of this.
[0089] FIG. 9 is a cross-sectional diagram of a ninth embodiment of the invention showing that a sleeved retrofit may be used within the scope of the invention.
[0090] Sidewall 902 may be an older sidewall not originally intended for use with the invention. Thus it may have a thickness greater than a sidewall originally designed for the invention, but may still be employed with the invention. Examples of the need for this include cases in which reassessment of the local environmental conditions indicate greater strength is called for, or in which the wall is degrading with age, found to be substandard and so on.
[0091] Tensional member 910 d may be attached to permanent anchors within or without the walls as previously shown, however, in this embodiment tensional member 910 d is affixed to an anchor in the form of elongated U-shaped sleeve 922 having an open bottom which may be easily affixed over the top of the older wall. Opening/attachment 924 may have an internal diameter substantially equal to the thickness of the wall, that is, equal to or slightly greater than the thickness of the wall. An attachment on opening 924 may assist in securing sleeve 922 to wall 902 as well.
[0092] FIG. 10 is a top planform view of a section of waterway seen from above, showing alternative arrangements of the tensional members. Sidewall 1004 may have first perpendicular tensional member 1010 d but may instead or additionally have second tensional member 1026 set at a first angle to the perpendicular and third tensional member 1028 set at a second angle.
[0093] Anchor 1030 may have multiple tensioning members affixed thereto, so as to allow side forces to be cancelled at the anchor point rather than in the wall.
[0094] FIG. 11 is a cross-sectional diagram of an tenth embodiment of the invention showing that only elevated guying tensional members may be used. First sidewall 1102 has only elevated tensional members such as member 1110 d , and thus the vertical navigation area is below the members: this embodiment may be either original equipment or a retrofit.
[0095] The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims. | A levee, canal or aqueduct wall is internally supported by tensional members such as cables which stretch across the width of the waterway. In embodiments the tensional members may leave a space between the topmost member and the water level, so as to allow for passage of sea vessels above the cables. Vertical or horizontal struts or individual anchors attached to the ends of the cables may be positioned within, partially within or outside of the walls. Due to the strength of the device, the waterway wall may even be constructed at an angle to the vertical, even leaning outwards. External guying tensional members may be anchored and may connect to the wall or the internal tensional members to provide tensional support to prevent motion in the inward direction, either temporarily (such as during construction) or permanently. | 4 |
CROSS REFERENCES TO RELATED APPLICATIONS
This is a continuation-in-part of copending application Ser. No. 288,846, filed Sept. 13, 1972, which is in turn a division of Ser. No. 137,627, filed Apr. 26, 1971, both now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to the production of cellular fused silica, and more particularly to the production of cellular fused silica having a bimodal closed cell structure. The invention also relates to such cellular fused silica and to the compound boron oxynitride, which is especially useful as the cellulating agent employed in the method of the invention.
Fused silica possesses a number of highly desirable properties, such as relative chemical inertness and resistance to attack by moisture, high electrical resistivity, and impermeability to liquids and gases. It is particularly known for its desirable refractory qualities, including a low thermal coefficient of expansion, high temperature resistance and high thermal shock resistance. Accordingly, fused silica is an exceedingly useful material in many applications including, for example, chemical apparatus, thermocouple protection devices, components of electronic systems, furnace parts and the like.
Dense, relatively nonporous fused silica blocks and bricks have long been known, being useful for the construction of refractory linings and the like, especially in open hearth steel furnaces. Open cell fused silica, i.e., cellular fused silica containing a multiplicity of cells which are inter-connected, is also well-known as a thermal insulating material. By virtue of its cellular structure, it is superior to the dense silica material in respect of its lighter weight, and also in having a lower thermal conductivity, which renders it more effective for thermal insulation. However, open cell fused silica is generally limited to use in dry environments, since its interconnected cells permit penetration of liquids. Moreover, open cell fused silica is generally characterized by low compressive strength and modulus of rupture as compared with the dense material, the strength decreasing with decreasing bulk density, thus precluding the use of open cell fused silica in many structural applications. For example, open cell fused silica having a bulk density of 0.5 g./cc. may have a compressive strength of only about 450 psi. and a modulus of rupture of only about 150 psi.
Closed cell silica, i.e., cellular silica wherein most or all of the cells are noncommunicating, has heretofore been produced, overcoming the disadvantageous permeability of the open cell type, but such materials have heretofore been characterized by poor mechanical strength, just as the open cell type. For example, U.S. Pat. Nos. 2,890,126 and 2,890,127 disclose an improved method of producing cellular silica with a closed cell structure, but the highest compressive strength reported therein is 125 psi. Further, due to the use of carbon and silicon carbide containing foaming agents, the silica foam thus made is frequently quite dark in color, often approaching black. This greatly degrades thermal insulating ability, due to increased thermal conductivity.
SUMMARY OF THE INVENTION
In accordance with the present invention, there is provided a method for making cellular fused silica having a very bright, clean white color due to the use of a foaming agent having no carbon or carbide content. The material has a bimodal closed cell structure, i.e., the material contains cells of two distinctly different size ranges and types, and substantially all of the cells are noncommunicating, i.e., not interconnected. The material consists of a multiplicity of relatively large closed cells, herein referred to as the primary cells, which are defined by a matrix which consists essentially of silica. However, the silica matrix itself additionally contains a multiplicity of relatively small but nonetheless macroscopic closed cells, herein referred to as the secondary cells, the secondary cells being substantially smaller than the primary cells, i.e., by at least one order of magnitude (e.g., a power of ten). Based upon microscopic measurements, the secondary cells in the silica matrix seldom exceed about 10 microns in size, their mean size being less than about 10 microns and usually considerably less than 10 microns. In contrast, the relatively large primary cells generally have a mean size in the range from about 0.5 mm. to about 5 mm. Both the primary and the secondary cells may vary considerably in shape from substantially spherical to highly irregular. In addition to having the advantage of being impervious to gases and liquids at room temperature and elevated temperatures, the cellular fused silica of the invention is characterized by a significantly higher compressive strength and modulus of rupture than closed cell silica materials heretofore available. Further, due to the absence of any carbonaceous blowing agent decomposition products, the whiteness, or brightness, of the fused silica is not discolored. This factor also results in lower thermal conductivity than previously achieved.
DESCRIPTION OF PREFERRED EMBODIMENTS
Bodies of cellular fused silica may be produced in accordance with the invention having bulk densities as low as about 0.4 g./cc. and up to about 1.2 g./cc. Bodies with considerably higher bulk densities may also be prepared, if desired, but there is seldom any advantage in such heavier bodies. Preferably, the bodies have a bulk density within the range from about 0.4 g./cc. to about 0.8 g./cc., such bodies providing a more or less optimum balance between light weight and mechanical strength. In general, the mechanical strength of the bodies tends to increase with increasing bulk density. Bodies having a bulk density of at least about 1.2 g./cc. may be produced having a compressive strength of at least about 4000 psi. and a modulus of rupture of at least about 2000 psi. Bodies having a bulk density of about 0.4 g./cc. may be produced having a compressive strength of at least about 370 psi. and a modulus of rupture of at least about 370 psi., while bodies having a bulk density of about 0.8 g./cc. may be produced having a compressive strength of at least about 2200 psi. and a modulus of rupture of at least about 1300 psi.
The method of the invention is particularly advantageous in being simple, short and relatively inexpensive, and in permitting the reproducible production of bodies of any desired bulk density within the range mentioned. The method is based in part upon the use of a novel cellulating agent, boron oxynitride. In accordance with the method, a substantially homogeneous mixture is formed of finely divided silica and from about 0.1% to about 10%, based upon the total weight of the mixture, of finely divided boron oxynitride. The mixture is then heated to a temperature of at least the melting point of the silica employed, whereupon the silica melts. While the cellulating mechanism is not fully understood, the boron oxynitride decomposes to produce gas, presumably oxygen, which is entrapped within the molten silica and which forms closed cells therein, producing a cellulated mass which, upon cooling, forms a rigid body of closed cell fused silica. The boron oxynitride apparently loses oxygen during the heating and is converted in whole or in part to boron nitride, which remains in the product but which is unobjectionable in view of its excellent high temperature properties and lack of discoloration effect. When the boron oxynitride is employed in the mixture in amounts of less than about 0.1% or more than about 10%, no appreciable cellulation occurs. Maximum cellulation is observed when the boron oxynitride is employed in the preferred amount of from about 0.3% to about 3.0%. In general, the mean size of the primary cells tends to increase with increasing amounts of boron oxynitride employed, and for reasons mentioned hereinafter, relatively small mean sizes of the primary cells are preferred. Accordingly, it has been found most preferable to employ the boron oxynitride in an amount of about 0.5%, which is within the range which produces maximum cellulation but which is low enough to result in relatively small primary cells.
Boron oxynitride suitable for the practice of the present invention may readily be prepared by heating boric acid in an ammonia atmosphere, increasing the temperature gradually or stepwise to a final temperature within the range from about 700°C to about 1300°C and continuing the heating at the final temperature until the desired composition is obtained. As the temperature rises, the boric acid slowly liberates water to produce boric oxide, which reacts slowly with the ammonia and is thereby nitrided to produce boron oxynitride. It will be apparent that boric oxide may be used as a starting material instead of boric acid, if desired. The temperature increase should be sufficiently slow as to avoid melting the boric oxide or intermediate products formed therefrom before the desired production of boron oxynitride occurs. Preferably, the boric acid is mixed with a suitable carrier material such as tricalcium phosphate to avoid agglomeration of the boric oxide, the tricalcium phosphate subsequently being leached out of the product, e.g., with dilute aqueous HCl. The preparation of boron oxynitride is illustrated in copending application Ser. No. 288,831, filed Sept. 13, 1972, now abandoned.
Boron oxynitride is a compound consisting of boron, oxygen, and nitrogen, but as with certain other compounds such as boron carbide, the proportions of its constituents are not rigorously governed by stoichiometry and the law of constant commposition. Rather, boron oxynitride is a compound of somewhat variable composition in that the proportions of oxygen and nitrogen in boron oxynitride may vary within certain limits, subject to the limitation that for each mole of boron, there must be precisely one mole of nitrogen and oxygen taken together. Thus, the compound may be represented by the formula BN 1 -m O m .
A series of boron oxynitride compounds has been prepared and tested for their utility as cellulating agents. This series of compounds corresponds to boron oxynitride having the formula BN 1 -m O m wherein m is a number from about 0.05 to about 0.3 and they have been found to be particularly suitable as cellulating agents. Accordingly, it is preferred that the boron oxynitride employed in the method of the present invention contain at least about 3% oxygen and have a maximum oxygen content of about 18%, this range of oxygen content corresponding to the stated range for the values of m. It has been observed that maximum cellulation occurs when the boron oxynitride contains about 13% oxygen.
EXAMPLE
Finely divided boron oxynitride is intimately mixed with finely divided silica to obtain a substantially homogeneous mixture containing 1% boron oxynitride, based on the total weight of the mixture. The silica, of the quartzite crystal form, analyzes 99.6% SiO 2 , and has a maximum particle size of about 50 microns, a mean particle size of about 8 microns, and a melting point of about 1680°C. The mixture is employed in a series of runs to produce cellular fused silica bodies according to the invention having various bulk densities. For each run, a graphite mold is employed with inner dimensions 22.8 × 11.4 × 6.4 cm., the inner surfaces being covered with a smooth coating of boron nitride, the mold being provided with a tightly fitting graphite cover, the inner surface of which is also covered with a smooth coating of boron nitride.
For each run, the mold is charged with the amount of mixture shown in the first column of the following table. The closed mold is then placed in a resistance heated carbon tube furnace and heated in a current of nitrogen to 1700°C, whereupon the mold is removed to the atmosphere and allowed to cool to room temperature, the resulting body then being removed from the mold.
The body produced in each run is a 22.8 × 11.4 × 6.4 cm. brick of cellular fused silica having a bimodal closed cell structure as described above, but having a very smooth, dense fused silica surface about 2 mm. thick which is substantially devoid of primary cells, each brick being extremely white and having very sharp edge and corner definition. The bodies consist essentially of silica, analyzing 99% SiO 2 , and their properties are set forth in the following table.
TABLE I__________________________________________________________________________Amount of Bulk Compressive Modulus of Thermal ConductivityMixture Density Strength Rupture (600°C)g. g./cc. psi psi cal./sec./cm.sup.2./°C/cm.__________________________________________________________________________ 660 0.4 370 370 0.000711000 0.6 1330 830 0.001091330 0.8 2200 1300 0.001482000 1.2 4000 2000 0.00233__________________________________________________________________________
In order to obtain a substantially homogeneous mixture of the silica and boron oxynitride with these materials in intimate contact, the boron oxynitride and silica should be finely divided, and generally the finer the better. It is preferred that the boron oxynitride have a maximum particle size of about 300 microns or less and a mean particle size of about 15 microns or less. The silica preferably has a maximum particle size of about 200 microns or less and a mean particle size of about 10 microns or less, and in general, the smaller the particle size, the smaller the primary cells.
Any of a wide variety of types of silica may be employed in the practice of the invention including, for example, quartz, tridymite, crystobalite, amorphous silica, fused silica powder and silicic acid. Relatively impure silica may be employed, if desired, although it is to be noted that the purity of the final product depends primarily upon the purity of the silica employed. In general, it is preferred to use relatively high purity silica since it is comparatively inexpensive and imparts its inherent desirable properties to the final product. Various oxidic impurities such as alumina, sodium oxide, potassium oxide, calcium oxide, ferric oxide, magnesia and titania are preferably avoided since they tend to increase the thermal conductivity of silica and also tend to reduce the melting point of the bodies produced. The silica is mixed with the desired amount of the boron oxynitride by any convenient technique such as dry or wet blending. Dry blending is most convenient although wet blending may in some cases give a slightly more intimate mixture.
If desired, the mixture may simply be placed in a tray and subjected to the heating step, or it may be compressed into a self-sustaining shape which is subjected to the heating step. In either case, cellulation and expansion will occur and a cellular fused silica body is obtained. Preferably, however, the mixture is placed in a suitable mold in order to produce a body having the desired shape. Suitable molds may be made of mullite, sintered alumina, sintered magnesia, boron nitride, refractory metals and the like. Carbon or graphite molds may also be employed, but since these materials tend to react extensively with the silica in the mixture, they are preferably coated on their inner surfaces with a material such as boron nitride. By employing molds of various shapes, cellular fused silica bodies of any of a wide variety of simple or complex shapes may be produced, such as blocks, bricks, pipes and the like. It has been found that the texture of the inner surfaces of the mold which come in contact with the bodies is accurately transferred to the corresponding outer surfaces of the bodies produced, and accordingly, it is preferred that the inner mold surfaces be as smooth as possible, in which case the surfaces of the resulting bodies are comparably smooth. Moreover, these smooth surfaces consist of dense fused silica having virtually no primary cells. Such smooth, dense surface layers may be up to several millimeters in thickness and are impervious to liquids and gases.
In accordance with a particularly preferred embodiment of the invention, a closed mold is employed, i.e., a mold of the desired configuration which has an opening to permit insertion of the mixture but which is provided with a cover for the opening, the assembly being mechanically strong enough to withstand the internal gas pressure generated during the heating step. By employing such closed molds, cellular silica bodies may be produced in various shapes and with any desired bulk density within the range from about 0.4 g./cc. to about 1.2 g./cc. or more. As long as the mold is charged with a weight of the mixture calculated to form a body having a bulk density of at least about 0.4 g./cc. if that weight occupied the entire volume of the mold, the mixture will cellulate and expand to completely fill the mold. If larger amounts of the mixture are employed, they necessarily produce bodies having proportionately higher bulk densities, since expansion beyond the confines of the mold is precluded. Accordingly, the bulk density of the final body is a function of the volume of the mold and the weight of the mixture placed therein, and cellular fused silica bodies having bulk densities from about 0.4 g./cc. to about 1.2 g./cc. or considerably higher may readily and reproducibly be made. The cellulated mass expands to contact the entire inner surface of the mold and its cover, and assuming that the entire inner surface is smooth, bodies may be produced in accordance with the invention of any desired bulk density within the specified range with their entire surface being smooth, dense and impervious. Closed rectangular molds may thus be employed to produce cellular fused silica bricks having exceptionally sharp edge and corner definition without any necessity for machining.
The heating step is carried out by heating the mixture to a temperature of at least the melting point of the silica employed. The melting point of silica is subject to some variation depending upon the type of silica and the nature of the impurities therein. Preferably a temperature from about 10°C to about 50°C above the melting point of the silica is employed in order to favor uniform melting within a relatively short time. There is generally no advantage to employing higher temperatures, although much higher temperatures of 2000°C and higher may be employed, if desired. It should be noted, however, that the size of the primary cells tends to increase with increasing temperatures, as a result of the lower viscosity of the molten silica and the greater volume of the gas liberated by the cellulating agent, and thus unnecessarily high temperatures are preferably avoided. The more rapidly the mixture is heated to the desired temperature, the better, since the faster the heating rate, the smaller the primary cells tend to be. It will thus be apparent that, while any of a wide variety of furnaces may be employed which are capable of generating the requisite temperatures, it will be preferred to employ furnaces which are capable of such rapid heating. Insofar as the product is concerned, the atmosphere during heating is not critical, air, nitrogen, the inert gases and the like being equally suitable. When carbon or graphite molds are employed, however, it is generally desirable to carry out the heating step in a nonoxidizing atmosphere to avoid adverse effects on the mold, the same applying to carbon or graphite internal furnace parts.
After the desired temperature has been reached, the resulting cellulated mass is cooled, whereupon it forms a rigid body of cellular fused silica. The cooling is preferably carried out rapidly to avoid or minimize crystallization of the silica.
Chemically, the resulting bodies consist essentially of silica, although they may also contain impurities derived from the starting material as well as residual boron nitride from the cellulating agent. The bodies are generally very bright white. By employing a relatively small amount of the cellulating agent and by also employing highly pure silica, bodies may be produced in accordance with the invention which contain 99% or more silica. In general, the bodies of the invention have the chemical properties characteristic of silica, being stable to various acids and corrosive gases, even at elevated temperatures.
The cellular fused silica bodies of the invention have outstanding physical properties. They are impervious to gases and liquids, both at room temperature and at elevated temperatures. They have very low thermal expansion coefficients. Their thermal shock resistance is indicated by the fact that the bodies may be heated to 1700°C and abruptly immersed in water at room temperature without cracking, spalling or any other observable effect. The bodies have outstanding mechanical strength, the compressive strength and the modulus of rupture tending to increase with increasing bulk density and also tending to increase with decreasing size of the primary cells for any given bulk density. The bodies are also characterized by low thermal conductivity, which tends to decrease with decreasing bulk density and which is apparently relatively unaffected by the size of the primary cells. The various desirable properties render the bodies especially useful as high temperature refractory thermal insulation in such apparatus as industrial furnaces and kilns, coke ovens, reaction chambers and the like.
Percentages referred to herein are by weight except as otherwise indicated. Modulus of rupture and compressive strength is determined in accordance with A.S.T.M. Designation C133-55. The mean size of the primary cells is measured by the linear intercept method using a conversion factor 1.16. Bulk density is determined by weighing the specimen in air and in water.
While the invention has been described herein with reference to certain examples and preferred embodiments, it is to be understood that various changes and modifications may be made by those skilled in the art without departing from the concept of the invention, the scope of which is to be determined by reference to the following claims. | Cellular fused silica having a bimodal closed cell structure is produced by mixing finely divided silica with finely divided boron oxynitride as a cellulating agent, and heating the mixture to a temperature of at least the melting point of the silica, whereby the silica melts and is cellulated by gas generated as a result of decomposition of the boron oxynitride. The cellular silica consists of a multiplicity of primary closed cells defined by a matrix consisting essentially of silica, the matrix also containing a multiplicity of secondary macroscopic closed cells which are at least an order of magnitude smaller than the primary cells. Cellular fused silica bodies according to the method of the invention are characterized by superior mechanical strength in addition to extreme whiteness and high purity of color, as well as other desirable properties, and are particularly useful for high temperature thermal insulation. Carefully controlled and defined shapes having very smooth surfaces may be obtained. | 2 |
This is a continuation-in-part of application Ser. No. 522,529, filed May 11, 1990, now abandoned.
FIELD OF THE INVENTION
This invention is directed to a method and composition useful for the preventative and curative treatment of exercise induced pulmonary hemorrhage in animals. More particularly, this invention relates to the health management of animal populations and to a method and composition for the prophylactic and curative treatment of exercise-induced pulmonary hemorrhage in animals, and, in particular, animals of the equine species, especially horses.
BACKGROUND OF THE INVENTION
Blood flowing from the nostrils of competitive Thoroughbred horses has been observed as far back as the sixteenth century. And despite over three hundred years of recognition, the condition has remained an enigma and until recently little has been attempted or achieved to uncover the underlying etiology and pathogenesis of this condition.
Historically, the source of blood at the nostrils was assumed to originate from within the nasal cavity because of the highly vascular nature of this organ. Post-exercise horses who exhibit blood at the nostrils are designated as "bleeders" and the condition termed "epistaxis", mistakenly analogous to epistaxis in man. However, two concepts emerged from observations of this condition, namely, that the blood originated in the nasal cavity, and that a positive relationship existed between bleeding episodes and poor competitive performance.
A recent retrospective survey of post-exercising horses with clinical evidence of blood at the nostrils positively identified the source of blood to have originated from the lungs. And repeated occurrences of pulmonary hemorrhage were precipitated by competitive exercise only. Further support of the hypothesis of the lung being the source of the blood was determined in horses with indwelling tracheostomy tubes that bled while being raced, the blood exiting the respiratory tract via the tracheostomy. By temporarily closing the tracheostomy, the blood flowed from the nostrils.
In the past, the paucity of diagnostic instrumentation which would allow safe examination of the equine upper respiratory tract with minimal restraint has been the primary factor impeding elucidation of this equine problem. The recent availability of the flexible fibreoptic endoscope into veterinary medicine has not only facilitated examination of the equine respiratory tract but has provided a means of locating the source of blood in bleeding horses.
The appearance of blood at the nostrils in exercising horses ranges from less than 1 to as high as 12 percent, but is generally about 0.5 to 2.5 percent. However, endoscopic surveys worldwide indicate that the actual prevalence of pulmonary hemorrhage is significantly higher than previously thought, with a range of 45 to 86 percent of racing or near maximal exercising horses. The incidence of pulmonary hemorrhage increases in direct proportion to the length of, and number of times, the endoscope is used on the individual animal. Histological examination of the caudal portion of the lung lobes revealed that 96 percent of horses that have raced had evidence of old alveolar hemorrhage.
The term used to describe the condition of pulmonary hemorrhage in horses without blood at the nostrils is exercise induced pulmonary hemorrhage (EIPH). EIPH is a more accurate description of bleeding in the racing horse than "bleeder". Multiple endoscopic surveys indicate that although pulmonary hemorrhage is experienced by a large number of racing or maximally exercising horses, epistaxis is a relatively infrequent manifestation of this phenomena. The frequency of occurrence of EIPH shows no relationship between the horse's sex, finishing position in the race, increasing age or distance raced. However, increased speed of exercise is directly associated with, and the common factor in, a higher incidence of EIPH in racing or maximally exercising horses.
Speeds greater than 240 meters per minute are necessary for a horse to have EIPH. The minimum speed required for a Standardbred to officially qualify to race competitively is about 755 meters per minute with the current world record about 885 meters per minute, whereas the average speed of racing Thoroughbreds is about 1050 meters per minute. EIPH occurs equally in both exercising Standardbreds and Thoroughbreds. However, the incidence of EIPH with epistaxis occurs only rarely in the racing Standardbred but more frequently in the racing Thoroughbred. Thus the speed of competition appears to be the constant factor designating whether a racing or maximally exercising horse will or will not have EIPH with epistaxis.
Repeated endoscopic examination of the same individual horse indicates that EIPH is not a random event but will repeatedly recur in the individual horse on a consistent basis. If a horse bleeds today, the chance of that same horse bleeding the next time it exercises or races is ten times higher than the horse who is not a bleeder. Periods of rest do not stop EIPH in horses. Upon return to training, and when maximal exercise form has been attained, bleeding recurs. Therefore, repeatability of EIPH is a consistent feature of this pathological phenomenon.
To determine the incidence of EIPH in post-racing horses, the animal was examined within 90 minutes of the completion of racing using a flexible fibreoptic endoscope. Both nostrils were examined for signs of hemorrhage. Other than the endoscopic observation of blood in the airways, a clear definitive set of clinical signs on which to establish a diagnosis of EIPH has not been documented. Astute horsemen report that horses with EIPH often have a distressed or anxious expression, "coolout" slowly, cough occasionally and swallow frequently. Coughing is not a consistent sign. Swallowing is a more consistent sign and is often the first indication of EIPH post-race. As the mucociliary blanket of the trachea clears the blood carried from the original source in the lungs, the blood pools on the floor of the larynx, flows onto the epiglottis, and then initiates the swallowing reflex.
Dyspnea is not commonly seen and if it occurs is a serious sign associated with extensive hemorrhage into the airways, exacerbation of pre-existing pulmonary disease or structural lung damage, ie. pulmonary abscess, pleural separation or tearing.
A characteristic pattern of clinical signs attributable to EIPH is further complicated by the variable response of the individual horse to the presence of blood in the airways. Moreover, the presence of blood at the nostrils is not a direct reflection of the severity of pulmonary hemorrhage or a determinant of the extent of the variability of performance noticeable upon initiation of pulmonary hemorrhage.
The major lesions of EIPH are multiple, separate and coalescing foci of moderately proliferative small airway disease accompanied by intense neo-vascularization of the bronchial circulation. These lesions are bilaterally symmetrical and confined to the dorsal angle of the lungs. Lesion extension occurs only along the dorsum of the lungs. Microscopic examination of the lungs of horses dying of EIPH has revealed engorgement of the pulmonary arteries, veins and capillaries, and rupture of the capillaries with hemorrhage into alveoli, bronchioles, bronchi, interstitium and subpleural tissue. The severity of engorgement and hemorrhage varied from almost nonexistent to massive in various areas of the lung, but the caudal portion of the lung lobes was the site of the most severe hemorrhage. Focally extensive pleural and interstitium fibrosis, and bronchiolitis were often accompanied by severe hemorrhage around large vessels and airways. Hemosiderophages also were present within this fibrous tissue, particularly at the junction of the pulmonary parenchyma and the deep layers of the pleura.
Latterly, numerous procedures have been performed in an attempt to prevent EIPH, with or without epistaxis, such as change of feed, bedding or ventilation, application of external or cold compresses to the nasal turbinate area, intermittent application of cold water over the thorax, and tying up the tail. More recently, various parenteral agents have been utilized in an effort to diminish the magnitude of EIPH in racing or near maximally exercising horses, namely atropine, estrogens, coagulants, clenbuterol (Ventipulmin™), ipratropium (Atrovent™), cromolyn (Intal™), intravenous saline infusion and steam inhalation. Hesperidin-citrus bioflavinoids administered orally do not alter the prevalence of the pulmonary hemorrhage. Enforced rest, with a convalescence length much longer than three months duration, does not change the repeatability of the EIPH episodes which recur, with or without epistaxis, upon resumption of training and upon attaining maximal exercise form. But most of these techniques and treatments are no rarely utilized.
Currently, the sulfamoyl-anthranilic acid derivatives, for example, furosemide (Lasix™) and ethacrynic acid, are parenterally administered to horses prior to racing in an attempt to control EIPH. Both of these drugs are potent diuretics which cause marked circulatory volume contraction in horses. The efficacy of these drugs in preventing EIPH has been extensively evaluated with widely variable results--sometimes stopping the hemorrhage, other times not stopping the hemorrhage, and yet at other times reducing the severity of the hemorrhage but not stopping the hemorrhage. Administration of these diuretics to horses having EIPH did not influence either the racing time or the systemic circulation physiology. However, administration of furosemide to horses negative for EIPH enhanced racing performance.
All the aforementioned procedures and drugs have been used in an attempt to prevent EIPH in exercising horses without fully understanding the underlying pathophysiology. EIPH, with or without epistaxis, in racing or maximally exercising Thoroughbred or Standardbred horses, causes greater financial losses than is encountered in other breeds of horses. Monetary loss following an EIPH episode ranges from slight to severe. EIPH occasionally can be fatal with affected horses dying almost instantaneously, this fatality often occurring during the latter portion of a race. But all affected EIPH horses are sub]ect to an economic loss of some degree. In spite of a multiplicity of endeavours used to minimize EIPH in racing or maximally exercising horses, it remains today a major worldwide problem in the horse racing industry.
Commercially formulated horse diets for strenuously exercising animals contain only naturally occurring feed ingredients and thus have high protein and energy levels. The protein level is adequate without the addition of non-protein nitrogen (NPN) in any form. Usually, at time of manufacture, or immediately prior to feeding, the animal's diet may be supplemented with vitamins and minerals. Regardless of the time of supplementation, only small amounts of alkaline potassium salts, if at all, may be added to the manufactured feed. Potassium, in large concentration, is normally present in all forages, grains and grain by-products. The availability of potassium to simple stomached animals is about 85 to 90 percent. Thus an animal's recommended daily potassium requirement is readily acquired through the daily feed intake and potassium deficiency symptoms infrequently develop. Consequently, potassium supplementation of the horse's daily feed is neither routinely implemented nor required.
The following reference discloses subject matter which is relevant to exercise-induced pulmonary hemorrhage: M. W. O'Callaghan et al., "Exercise-Induced Pulmonary Hemorrhage in the Horse: Results of a Detailed Clinical, Post-Mortem and Imaging Study", Equine Veterinary Journal (1987) 19(5), 384-434.
SUMMARY OF THE INVENTION
This invention relates to the discovery that a mixture of urea, alkaline potassium salts and magnesium salts exhibits surprisingly effective activity against EIPH, and, in particular, is useful in the treatment of EIPH.
Specific compositions and methods of application of urea, alkaline potassium salts and optional magnesium salts mixtures have now been discovered. Use of such compositions and methods relate to the prophylactic and curative treatment of EIPH in animals, and in particular, in animals of the equine species, notably horses. These new methods comprise administration to animals of an effective amount of a mixture of urea, alkaline potassium salts and, if required, magnesium salts. More specifically, it is found that when urea-alkaline potassium salts and, optionally, magnesium salts compositions are administered orally to said animals, daily water intake increases, urine excretion increases by an increased glomerular filtration rate and the urine flow rate increases by an osmotic diuretic effect. Magnesium salts are required if the total daily feed consumed by the horse provides insufficient magnesium salts.
This invention specifically relates to a method for the suppression of EIPH in animals comprising administration to the animals of an effective amount of a mixture of urea, alkaline potassium salts and, if required, magnesium salts.
Representative compounds found useful in the prophylactic and curative treatment of EIPH in populations of animals, including affected members, comprise a mixture of urea and alkaline potassium salts and, if required, magnesium salts. Urea used in these formulations can be in the free base form or a pharmaceutically acceptable salt thereof. The following alkaline potassium salts are all well known and available commercially and have been found to be effective in treating horses in accordance with the present invention:
Potassium chloride
Potassium citrate
Potassium phosphate
Potassium nitrate
Potassium sulfate
Potassium acetate
Potassium gluconate
Potassium silicate
Of the foregoing, potassium chloride appears to possess the most desirable therapeutic characteristics. Potassium chloride is advantageous because it is a non-toxic, non-corrosive, readily available, chemically stable compound.
The following magnesium salts are all well known and available commercially, and have been found to be effective in treating horses in accordance with the present invention:
Magnesium oxide
Magnesium hydroxide
Magnesium phosphate
Magnesium sulfate
Magnesium acetate
Magnesium chloride
Magnesium adipate
Magnesium lactate
Magnesium gluconate
Magnesium carbonate
Of the foregoing, magnesium oxide appears to possess the most desirable therapeutic characteristics. Magnesium oxide is advantageous because it is a non-toxic, readily available, chemically stable compound.
In a particular aspect, the present invention relates to the prophylactic and curative treatment of EIPH in animals, including horses, and encompasses a method of prophylactic and curative therapy using a pharmaceutical composition, feed mixture, feed and liquid supplements containing a mixture of urea, alkaline potassium salts and, optionally, magnesium salts. In another aspect, this invention provides pharmaceutical and veterinary preparations and feed and liquid compositions for prophylactic and curative treatment of EIPH utilizing a mixture of urea, alkaline potassium salts and magnesium salts.
In broad terms, the invention is directed to a method for treating or preventing exercise-induced pulmonary hemorrhage in an animal which comprises administering to the animal a mixture of urea and pharmaceutically acceptable salts thereof, an alkaline potassium salt selected from the group consisting of potassium chloride, potassium citrate, potassium phosphate, potassium nitrate, potassium sulfate, potassium acetate, potassium gluconate and potassium silicate and, optionally, a magnesium salt selected from the group containing magnesium oxide, magnesium hydroxide, magnesium phosphate, magnesium sulfate, magnesium acetate, magnesium chloride, magnesium adipate, magnesium lactate, magnesium gluconate and magnesium carbonate.
In a particular embodiment, the urea can be in the free base form, the alkaline potassium salt can be potassium chloride and the magnesium salt can be magnesium oxide. The mixture can comprise about 1 to about 65 percent by weight urea, about 0.05 to about 50 percent by weight alkaline potassium salts and about 0.25 to about 25 percent by weight magnesium salts.
The alkaline potassium salt can be present in an amount ranging from about 0.05 to about 45 percent by weight, or more specifically from about 0.05 to about 35 percent by weight. Alternatively, the alkaline potassium salt can be present from about 0.25 to about 0.8 parts by weight per 1 part by weight of urea, or more specifically from about 0.6 parts by weight per 1 part by weight of urea
The magnesium salt can be present in an amount ranging from about 1 percent to about 25 percent by weight. Alternatively, the magnesium salt can be present from about 0.05 to about 0.25 parts by weight of urea.
The mixture can be incorporated into a feed or liquid composition and fed to the animal on a daily basis. The mixture can be included in the daily diet of the animal in an amount between about 10 to about 1,000 g. The animal treated with the mixture can be a member of the equine species, and specifically a horse.
The invention is also directed to a composition for the prophylactic and curative treatment of exercise-induced pulmonary hemorrhage in an animal comprising: (a) urea or a pharmaceutically acceptable salt thereof; (b) an alkaline potassium salt selected from the group consisting of potassium chloride, potassium citrate, potassium phosphate, potassium nitrate, potassium sulfate, potassium acetate, potassium gluconate, potassium silicate; and (c) a magnesium salt designated from the group consisting of magnesium oxide, magnesium hydroxide, magnesium phosphate, magnesium sulfate, magnesium acetate, magnesium adipate, magnesium lactate and magnesium gluconate.
The urea can make up about 1 to about 65 percent by weight of the composition, the alkaline potassium salt can make up about 0.05 to about 45 percent by weight of the composition and the magnesium salt can make up about 1 to about 25 percent by weight of the composition. The alkaline potassium salt can be potassium chloride and can be present in the composition in an amount ranging from about 0.05 to about 35 percent by weight of the composition. The ratio of urea to potassium chloride can be about 1 part by weight urea to about 0.6 parts by weight potassium chloride. Urea and the potassium chloride can be mixed with a pharmaceutically acceptable carrier. The magnesium salt can be magnesium oxide and can be present in the composition in an amount ranging from about 1 to 10 percent by weight of the composition. The ratio of urea to magnesium oxide can be about 1 part by weight urea to about 0.16 parts by weight magnesium oxide. Urea and magnesium oxide can be mixed with a pharmaceutically acceptable carrier. Urea, potassium chloride and magnesium oxide can be mixed with a pharmaceutically acceptable carrier.
DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION
The urea used in the practice of this invention can be in the free base form or in the form of a pharmaceutically acceptable salt. For example, urea may be readily converted to one of its nontoxic acid addition salts by customary methods used in the chemical art. Nontoxic salts of this invention can be formed from free base urea and an acid which is pharmaceutically acceptable in the intended dosages. Such salts include those prepared from inorganic acids, organic acids, higher fatty acids, higher molecular weight acids, and the like. Exemplary acids are hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methane sulfonic acid, benzene sulfonic acid, acetic acid, propionic acid, malic acid, succinic acid, glycolic acid, lactic acid, salicylic acid, benzoic acid, nicotinic acid, phthalic acid, stearic acid, oleic acid, abietic acid, and the like.
The amount of urea in such preparations may be as little as 1 percent by weight or as high as about 50 percent by weight. Below 1 percent by weight, the urea is generally too low to be therapeutically useful. The upper limit of about 50 percent by weight is based on the solubility limit of urea in water.
The amount of alkaline potassium salts added to the preparation should be in the range of about 0.05 to 50 percent by weight. Below about 0.05 percent by weight, the alkaline potassium salts are generally ineffective. Amounts of alkaline potassium salts in excess of about 50 percent by weight have been found to be unnecessary and wasteful. Generally no more than about 45 percent by weight, and preferably, no more than about 42 percent by weight of alkaline potassium salts are used. As a general rule, the amount of alkaline potassium salts used is based on the amount of urea used. Good results are obtained when the amount of alkaline potassium salt is about 25 to 80 percent by weight of the weight of urea in the preparation, with alkaline potassium salts at about 35 percent by weight of urea providing particularly good results.
The following alkaline potassium salts are generally effective in the prophylactic and curative treatment of EIPH in horses
Potassium chloride
Potassium citrate
Potassium phosphate
Potassium nitrate
Potassium sulfate
Potassium acetate
Potassium gluconate
Of these, potassium chloride, hereinafter referred to simply as KCl, is usually the most suitable for use in pharmaceutical compositions, feed mixtures, feed and liquid supplements for the prophylactic and curative treatment of EIPH in the equine species, including horses.
The amount of magnesium salts added to the preparation should be in the range of about 1 to about 25 percent by weight. Below about 1 percent by weight, the magnesium salts are ineffective. Amounts of magnesium salts above 25 percent are wasteful and unnecessary. Generally, no more than about 20 percent by weight, and preferably, no more than about 15 percent by weight of magnesium salts are used. Good results are obtained when the amount of magnesium salt is about 5 to about 25 percent by weight of the urea in the preparation, with magnesium salts at about 10 percent by weight of urea providing particularly good results.
The following magnesium salts are generally effective in the prophylactic and durative treatment of EIPH in horses:
Magnesium oxide
Magnesium hydroxide
Magnesium phosphate
Magnesium sulfate
Magnesium acetate
Magnesium chloride
Magnesium adipate
Magnesium lactate
Magnesium gluconate
Magnesium carbonate
Of these, magnesium oxide, hereinafter referred to simply as MgO, is usually the most suitable for use in pharmaceutical compositions, feed mixtures, feed and liquid supplements for the prophylactic and curative treatment of EIPH in the equine species, including horses.
The compounds defined above are readily absorbed into the blood stream from the stomach and intestinal tract of the treated animal when taken orally, and therefore the preferred method of treatment is to administer the compound orally to the animal. This is also the safest, simplest and most practical route of administration. Optional modes can be used where, for example, the animal is not eating or cannot swallow or has difficulty in swallowing. Other acceptable methods of administration which permit the compound to be absorbed in the gastrointestinal tract or which deliver a solution of the compound directly to the bloodstream (intravenous injection) can then be employed.
The method of administration may also vary depending on the purpose of administration. For example, use as a prophylaxis or preventative treatment or as a treatment of affected animals can require different methods of treatment and dosage forms easily formulated by those skilled in the art.
The dosage regimen in carrying out this invention utilizing the urea--KCl--MgO mixture for treatment of EIPH of horses are those which insure maximum therapeutic response. The average effective daily dose of the urea--KCl--MgO mixture is between about 100 mg/kg to about 2000 mg/kg of body weight, with about 600 to about 1250 mg/kg of body weight being preferred.
The treatment of animals can normally be accomplished by incorporating an effective amount of the compound in the animal's diet as a solid or liquid feed supplement, or dissolved in the animal's liquid intake. The urea--KCl--MgO mixture for use in the practice of the present invention includes compounds which are non-toxic to the animals, including horses, when administered daily to the animal in the animal's feed diet in concentrations of about 10 to about 1,000 g. Anti-EIPH effects can be realized also for the various urea, alkaline potassium salts and magnesium salts when administered daily in the animal's feed diet in concentrations of about 10 to about 1,000 g.
Compositions useful in the practice of the present invention can be prepared in forms suitable for administration by compounding an effective single dose amount of the compound with known pharmaceutically acceptable carrier ingredients generally employed in the preparation of theurapeutic compositions of the type which are provided as tablets, hard capsules, powders, granules and aqueous suspensions.
Compositions intended for oral use may be prepared according to methods known generally in the art. Such compositions may contain one or more pharmaceutically acceptable carrier agents selected from the group consisting of sweetening agents, flavoring agents, coloring agents and preserving agents. In general, the composition will contain a mixture of urea, alkaline potassium salts and magnesium salts in admixture with non-toxic pharmaceutically acceptable excipients. Exemplary excipients are: interdilutants such as calcium carbonate, sodium carbonate, lactose, calcium phosphate, and sodium phosphate; granulating or disintegrating agents, for example, maize, starch, and algenic acid; binding agents, for example, starch, gelatin and acacia; and lubricating agents, for example magnesium stearate, stearic acid, and talc. Tablets may be uncoated or they may be coated by known techniques to make them more therapeutically effective, for example, to delay disintegration or absorption, or to make them more palatable, or for other reasons for which orally administered mixtures of urea, alkaline potassium salts and magnesium salts have been previously provided in coated form.
Formulations for oral use may also be presented as hard gelatin capsules wherein the mixture of urea, alkaline potassium salts and magnesium salts is admixed with an inert solid diluent, for example, calcium carbonate, calcium phosphate and kaolin.
Aqueous solutions containing a mixture of urea, alkaline potassium salts and magnesium salts can also be utilized, when desirable. Excipients suitable for aqueous suspensions may be employed, if desired. Such excipients include: suspending agents, for example, sodium carboxmethylcellulose, methylcellulose, hydroxypropylmethylcellulose, sodium alginate, polyvinylpyrrolidone, gum tragacanth and gum acacia; dispersing or wetting agents which may be a naturally occurring phosphatide, for example, lecithin, condensation products of an alkylene oxide with fatty acids, for example, polyoxyethylene stearate, condensation products of ethylene oxide with long-chain aliphatic alcohols, for example, heptadecaethyleneoxy-cetanol, condensation products of ethylene oxide with partial esters derived from fatty acids and a hexitol, for example polyoxyethylene sorbitol monoleate, and condensation products of ethylene oxide with partial esters derived from fatty acids and hexitol anhydrides, for example, polyoxyethylene sorbitan monoleate. The said aqueous suspensions may also contain one or more preservatives, for example, ethyl, or n-propyl-p-hydroxy benzoate, one or more coloring agents, one or more flavouring agents, and one or more sweetening agents such as sucrose.
Dispersible powders and granules suitable for preparation of an aqueous suspension by the addition of water provide the mixture of urea, alkaline potassium salts and magnesium salts in admixture with dispersing, suspending or wetting agent. Additional excipients, for example, sweetening, flavoring and coloring agents may also be present.
The pharmaceutical compositions may be in the form of a sterile injectionable preparation, for example, as a sterile injectable aqueous suspension. This suspension may be formulated according to available art methods using suitable dispersing or wetting agents and suspending agents such as those which have been mentioned above, or others. This sterile injectable preparation may also be a sterile injectable solution or suspension in a non-toxic parenterally acceptable diluent or solvent, for example, as an aqueous solution buffered to a pH of about 4.0 to 7.0 and made isotonic with sodium chloride.
Further, the mixture of urea, a single alkaline potassium salt and a single magnesium salt may be administered alone or in admixture with a mixture of urea other alkaline potassium salts and other magnesium salts, or with other agents having the same, similar or different pharmacological properties.
The following examples of preferred embodiments of this invention, showing veterinary and pharmaceutical compositions, were all prepared using urea, KCl and MgO. Similar granules, capsules, tablets, feed and liquid supplements can be prepared containing other of the designated alkaline potassium salts and magnesium salts.
DESCRIPTION OF PREFERRED EMBODIMENTS
Compositions containing urea--KCl--MgO mixtures in dry powder or granular form should generally contain only about 65 weight percent of urea and preferably no more than about 58 weight percent; and should generally contain only about 50 weight percent of KCl and preferably no more than about 35 weight percent, and should generally contain only about 25 weight percent of MgO and preferably no more than about 10 weight percent.
Formulations containing urea--KCl--MgO preparations in aqueous solution should generally contain only about 50 weight percent of urea and preferably no more than about 35 weight percent, and should generally contain only about 25 weight percent of KCl and preferably no more than about 20 weight percent and should generally contain only about 20 weight percent of MgO and preferably no more than about 10 weight percent.
The following examples are provided to illustrate the activity of various urea--KCl--MgO formulations in the prophylactic and curative treatment of EIPH in racing or maximally exercising horses. The examples are not to be taken as an exhaustive list of the possible methods and compositions for using the urea--KCl--MgO formulations and the benefits resulting from their use. The examples do, however, give some indication of the broad scope of this invention, specifically, the suitability of urea--KCl--MgO preparations for a variety of situations.
EXAMPLE 1
A series of blood samples were collected from various horses to demonstrate that in the Thoroughbred and Standardbred breeds of racing horses elucidation of the etiopathogenesis and verification of EIPH through implementation of hematology and biochemical screening procedures are uninformative and valueless. Even though both breeds are exposed to a wide variety of environmental conditions throughout the world the incidence of bleeding from the nostrils, ie. epistaxis, is greater in the Thoroughbred than the Standardbred breed.
It is thought that the occurrence of bleeding in racing or maximally exercising horses may be caused by an inherited genetic factor which is expressed more often in Thoroughbreds than Standardbreds. However, the incidence of EIPH in both breeds of horses varies similarly statistically (between 45 to 86 percent) and anatomically (caudal diaphragmatic lung lobes), whereas the incidence of bleeding in Thoroughbreds varies from less than 1 up to 12 percent but occurs only rarely in Standardbreds.
Thus the disparity in the incidence of bleeding between these two breeds of racing horses may be due to either: (1) genetic differences between the hematology and biochemical values, or (2) the speed of racing or maximally exercising.
To examine the possibility of a heritable genetic difference occurring between the hematological and biochemical levels of racing Thoroughbred and Standardbred horses a series of blood samples were collected from eight racing Thoroughbreds and eight racing Standardbreds for laboratory analysis and the results recorded.
The age of the eight racing Thoroughbreds in this test ranged between 3 to 7 years with an average age of 4.2 years, body weight ranged between 420 and 468 kg. with an average of 444 kg. The eight racing Standardbred horses ranged in age between 2 to 9 years with an average of 3.5 years, body weight ranged between 397 and 470 kg. with an average of 439 kg.
The average hematogolical and biochemical levels of the said test horses are listed below:
______________________________________ Standard- Thorough- bred bredHematology and Biochemistry n = 8 n = 8 Units______________________________________White cell count 7.3 6.9 th/mm.sup.3Red cell count 7.7 8.4 mil/mm.sup.3Hemoglobin 12.9 13.0 g/dlHematocrit 33.9 30.6 %Platelet count 180 174 th/mm.sup.3Glucose 63 64 mg/dlBlood urea nitrogen 22 14 mg/dlCreatinine 1.6 1.5 mg/dlSodium 141 138 meq/dlPotassium 3.5 3.7 meq/dlCalcium 12.2 11.8 mg/dlPhosphorus 3.4 3.6 mg/dlTotal protein 6.0 5.5 L* g/dlAlbumin 3.5 3.6 g/dlGlobulin 2.5 1.9 L g/dlBilirubin total 2.0 2.2 mg/dlAlbumin/Globulin ratio 1.4 1.9 HCalculated Osmolality 281 272Chloride 100 100 meq/lCarbon dioxide 29 26 meq/lAnion gap 12 12Cholesterol 91 102 mg/dl______________________________________ *L Lower than normal value H Higher than normal value
Comparison of the measured hematological and biochemical parameters between the two breeds of racing horses indicates that there is a striking similarity between the two sets of hematological and biochemical values for Thoroughbred and Standardbred horses rather than a distinct demonstrable difference. Since the incidence of EIPH in Thoroughbreds and Standardbreds is similar, it appears from these examples that the difference in the incidence of EIPH with epistaxis between racing Thoroughbreds and Standardbreds must be directly related to the speed of racing and is not a visible expression of a heritable genetic factor. The probability of speed being a factor in having EIPH, with or without epistaxis, has credence since it has been found that a speed greater than 240 meters per minute is necessary to produce EIPH and that the average speed of racing Thoroughbreds is about 1050 meters per minute, whereas the world record speed of a Standardbred pacer is about 885 meters per minute.
EXAMPLE 2
This example illustrates the effect of daily oral feeding in the grain ration of a dry urea--KCl--MgO composition to eliminate or prevent EIPH in a 5 year old Standardbred mare, 440 kg. body weight, with a long history of EIPH episodes occurring during racing. The mare is currently racing with a pre-race intravenous bleeder injection to prevent EIPH during the race.
A dry feed supplement intended as a feed for racing and maximally exercising horses was prepared by blending about 4 percent weight of urea, about 3 percent weight of KCl and about 0.2 percent weight of MgO in a basic performance-type horse ration containing:
______________________________________Ingredient Amount______________________________________Oats, whole 4767 gSoybean Oil Meal 113 gSweet Feed, 12% C.P. 1589 gSalt, Cobalt-Iodized 60 gDicalcium Phosphate 60 gVitamins and Minerals 75.0 gVitamin A 67500 I.U.Vitamin D 18000 I.U.Vitamin E 180 I.U.Vitamin B12 180 mcgNiacin 187.5 mgThiamine 37.5 mgRiboflavin 60.0 mgPantothenic Acid 75.0 mgCholine Chloride 1.125 gFolic acid 18.0 mgIodine 1.5 mgManganese Sulphate 506.25 mgZinc Oxide 1.5 gCobalt Sulphate 11.25 mgCopper Sulphate 112.5 mgFerrous Sulphate 1.125 gFluorine (max) 150.0 mg______________________________________
The total daily feed intake consisted of about 13 pounds (5.9 kg) of timothy hay, about 3.3 pounds (1.5 kg) of alfalfa cubes, about 11.25 pounds (5.1 kg) of whole oats and about 3.75 pounds (1.8 kg) of commercially mixed grain to which was added the dry urea--KCl--MgO composition at a level of about 4 percent weight of urea, about 3 percent weight of KCl and about 0.2 weight percent of MgO. Salt (NaCl) was added at a level of supplementation to provide the test animal a total daily intake of about 1600 mEq Na + . Supplementation of the daily grain ration with about 4 weight percent of urea, about 3 weight percent of KCl and about 0.2 weight percent of MgO provided the test animal a total daily intake of about 4200 mEq of urea, about 6200 mEq of K + and about 3000 mEq of Mgz 2+ .
The dosage regimen in carrying out this test, where the said composition was used for the prophylactic or curative therapy of EIPH during racing or maximal exercise in horses, was used to insure maximum therapeutic response.
The effective daily dosage attained by the animal for the active ingredient urea of this invention was between about 475 mg/kg body weight to about 550 mg/kg body weight, and for KCl was between about 335 mg/kg to about 375 mg/kg body weight, and for MgO was between about 70 mg/kg body weight to about 80 mg/kg body weight.
Demonstrable effectiveness for this route of administration of this invention in preventing or eliminating EIPH during racing or maximal exercise in a horse is illustrated by the race results produced by this 5 year old Standardbred mare in a total of thirteen consecutive officially sanctioned harness races.
The thirteen races which were run during the spring and summer racing season by the 5 year old Standardbred mare were all performed within a single class of competition. The first three races of this series were run with the usual preface intravenous bleeder injection. The next seven races were performed without a pre-race intravenous bleeder injection but with the said composition supplemented at maximum therapeutic level in the daily grain ration. The final three races of this series again were run with only a pre-race intravenous bleeder injection and without the supplementation of the said composition. The economic placement, total monetary winnings and winnings per start for the thirteen races are listed below:
__________________________________________________________________________ Total Monetary Economic Placement Monetary ReturnsRaces 1 2 3 4 5 No. (%) Earnings ($) Per Start ($)__________________________________________________________________________Six races - pre-race 1 -- 1 -- 1 3/6 50 1,656 276intravenous bleederinjectionSeven races - daily 1 3 1 -- 1 5/7 71 3,140 448urea-KCl--MgO composition__________________________________________________________________________
Winnings per start in this series of thirteen races increased by more than 62 percent with the addition of the said composition to the daily grain ration over the use of a pre-race intravenous bleeder injection for prevention of EIPH during the race. performance.
No evidence of EIPH was observed in this horse while racing, or after racing, or during the entire seven races while consuming the dry urea--KCl--MgO formulation at maximum therapeutic level in the daily grain ration.
Urine samples, collected from the first and second place winners by authority of the Federal Racing Commission, were laboratory tested for the presence of illegal performance enhancing drugs and were always certified negative and the tests were never masked or compromised by the oral use of this invention.
During the time the said preparation was supplemented in the daily grain ration there was a noticeable improvement in the horse's demeanor, power, endurance and speed during training which carried over to surprisingly influence the official race results. Upon cessation of daily intake of this invention, the horse rapidly reverted to the previous level of performance
Use of dry urea--KCl--MgO composition added to the daily grain ration at a sufficient level to ensure maximum therapeutic response eliminated or prevented EIPH in a horse with a long standing history of EIPH occurring during racing.
EXAMPLE 3
The effectiveness of dry urea--KCl--MgO composition in treating and preventing EIPH in a 4 year old Standardbred mare, 428 kg body weight, with a long history of EIPH occurring during racing was determined. The mare was currently utilizing a pre-race intravenous bleeder injection for the prevention of EIPH during racing.
The dry urea--KCl--MgO composition, as well as supplemental NaCl, were admixed into the daily grain ration so that about 4 weight percent of urea, about 3 weight percent of KCl and about 0.2 weight percent of MgO were consumed by the test animal. In addition, about 3.3 pounds (1.4 kg) of alfalfa cubes and about 12 pounds (5.5 kg) of alfalfa-timothy mixed hay were the daily roughage intake of the daily ration.
The effective dosage of the composition consumed daily by the test animal was between about 500 mg/kg body weight to about 585 mg/kg body weight for urea, was between about 200 mg/kg body weight to about 375 mg/kg body weight for KCl and was between about 50 mg/kg to about 60 mg/kg for MgO. The dosage was preferably no more than about 575 mg/kg body weight of urea, about 350 mg/kg body weight of KCl and about 55 mg/kg body weight of MgO. The daily ration supplemented with this invention provided a daily intake of about 4200 mEq of urea, about 6000 mEq of K + and about 2400 mEq of Mg 2+ . The supplemental NaCl provided the test animal a total daily intake of about 1500 mEq Na + . The dosage regimen of the said composition was such as to ensure maximum therapeutic response in treating and preventing the occurrence of EIPH in a 4 year old Standardbred mare with a long standing history of EIPH occurring while racing.
The effectiveness of this invention in preventing and treating an EIPH prone animal and the competitive racing results resulting therefrom are documented below.
Initially, four races at the start of the autumn racing meet were completed with a pre-race intravenous bleeder injection which resulted in no EIPH episodes and a single economic placement (5th). Subsequently, a two month rehabilitation period away from the racetrack environment intervened. Upon return to racing, a series of nine consecutive races were run in a single competitive class. The first six races were performed using a pre-race intravenous bleeder injection as a protective measure against EIPH whereas the final three races were performed without a pre-race intravenous bleeder injection but with the maximum therapeutic dosage of dry urea-KClMgO composition being consumed daily in the grain ration to prevent or eliminate EIPH during racing.
The dry urea--KCl--MgO composition was slowly introduced into the daily grain ration and maximum therapeutic dosage was reached only after the eighth day. Full dosage was reached twelve days before the sixth race and was maintained at that dosage level until completion of the test.
No gastrointestinal upset or colic occurred during the test and daily grain consumption and palatability were unaffected with admixture of this invention. A noticeable increase in water intake and increased urine excretion were obvious before the third day of supplementing the daily grain ration with this invention. Both of the aforementioned physiological parameters increased in quantity until full daily dosage was reached and remained at that elevated level until cessation of the test. Before the second day after the end of the test both the quantities of water consumed and urine produced noticeably decreased and returned to more normal amounts for a racing horse not fed the composition of this invention.
Two blood samples were collected for determination of hematological and biochemical parameters. The first blood sample was obtained after the sixth race and before the start of feeding the said composition in the daily grain ration, and the second blood sample was collected after the ninth race and the completion of the test. The laboratory values obtained for hematology and biochemistry of the two blood samples are listed below.
______________________________________ Blood Sample 1 2Hematology and Biochemistry Day 0 Day 29 Units______________________________________White cell count 7.0 7.1 th/mm.sup.3Red cell count 8.7 10.0 mil/mm.sup.3Hemoglobin 14.1 16.1 g/dlHematocrit 36.4 42.1 %Platelet count 170 180 th/mm.sup.3Glucose 55 L* 62 mg/dlBlood urea nitrogen 15 17 mg/dlCreatinine 1.6 1.5 mg/dlSodium 146 139 meq/dlPotassium 3.7 3.8 meq/dlCalcium 12.9 12.9 mg/dlPhosphorus 2.4 L 3.1 mg/dlTotal protein 5.6 L 6.2 g/dlAlbumin 3.5 3.3 g/dlGlobulin 2.1 L 2.9 g/dlBilirubin total 1.8 1.3 mg/dlAlbumin/Globulin ratio 1.7 H 1.1Calculated Osmolality 287 275Chloride 103 100 meq/lCarbon dioxide 36 H 26 meq/lAnion gap 7 13Cholesterol 85 95 mg/dl______________________________________ *L Lower than normal value H Higher than normal value
The economic placement, monetary winnings and monetary returns per start for the entire nine races, the six races run with a pre-race intravenous bleeder injection and the three races competed with only this invention supplemented into the daily grain ration are listed below:
__________________________________________________________________________ Total Monetary Economic Placement Monetary ReturnsRaces 1 2 3 4 5 No. (%) Earnings ($) Per Start ($)__________________________________________________________________________Nine - total 1 1 1 1 2 6/9 66 1,931 214Six - pre-race 1 -- -- -- 2 3/6 50 1,195 199intravenous bleederinjectionThree - daily urea- -- 1 1 1 -- 3/3 100 736 245KCl--MgO composition__________________________________________________________________________
It specifically appears from the race results that with no change in management procedures other than the supplementation of the daily grain ration with this invention, the monetary return per start increased more than 23 percent over that attained with a pre-race intravenous bleeder injection. It is logical to conclude that the increased economic returns and absence of EIPH occurring during racing are directly related to the daily intake of this invention in the animal's daily grain ration.
Observable clinical manifestations of colic, gastrointestinal and endocrinological abnormalities were not apparent from close observation of the test animal during the test period.
Throughout the twenty-nine day test period, with supplementation of the daily grain ration with the dry urea--KCl--MgO composition, and during or after many training sessions and during or after competing in three officially sanctioned races, no characteristic clinical signs of, or endoscopic evidence of EIPH, developed in this 4 year old Standardbred mare, which previously had a long history of EIPH occurring while racing.
As this example illustrates, not only is EIPH eliminated or reduced in a 4 year old racing Standardbred mare with a long history of EIPH episodes occurring while racing, but specifically also demonstrates the suitability of this invention to enhance an animal's racing or maximal exercising performance up to its genetic potential.
EXAMPLE 4
The safety of long-term administration and possible cumulative effects of the urea--KCl--MgO composition in aqueous solution when given daily and orally for a 282 day period at maximum therapeutic dosage for the prevention or elimination of EIPH in a 4 year old Standardbred gelding, 450 kg body weight, during the pre-race training period and official harness race meet was investigated. Hematological and biochemical values obtained from four blood samples were compared to determine if the measured parameters were pathophysiologically altered by the long-term daily consumption of the said composition admixed into the daily grain ration.
The animal's daily feed intake consisted of about 3.3 pounds (1.4 kg) of alfalfa cubes and about 10 pounds (4.5 kg) of alfalfa hay for roughage and grain, about 11 pounds (5 kg) of whole oats and about 3.5 pounds (1.5 kg) of commercial mixed grain (see Example 2).
The daily dosage of the said composition in aqueous solution provided the test animal with between about 485 mg/kg body weight and about 550 mg/kg body weight of urea and for KCl between about 260 mg/kg body weight and about 350 mg/kg body weight. Thus, the test animal was provided with a total daily intake of about 4200 mEq of urea and about 6400 mEq of K + . NaCl was supplemented daily to the test animal to provide a total daily intake of about 1500 mEq Na + . MgO was supplemented daily to the test animal to provide a total daily intake of about 3300 mEq of Mg 2+ .
At various times during the 282 day test period, the aqueous solution was supplied to the test animal in the drinking water, admixed into the oats and mixed grain or poured onto the alfalfa hay or cubes. Palatability of this composition was unaffected regardless of the route of administration. The test animal did not react adversely to the various oral routes of intake nor at any time throughout this test period show any physical discomfort or clinical evidence of gastrointestinal upset or colic.
The hematological and biochemical levels obtained from blood samples collected: (1) immediately prior to the start of the long-term feeding test of the said composition in aqueous solution (Day 0); (2) midway during the training period (Day 168); (3) immediately prior to the start of the race meet (Day 203); (4) several days after the eighth race of the race meet (Day 245); and, (5) two days after the eleventh race of the race meet (Day 282), are listed below:
__________________________________________________________________________ Blood Sample 1 2 3 4 5 Day 0 Day 168 Day 203 Day 245 Day 282 Units__________________________________________________________________________Hematology andBiochemistryWhite cell count 8.8 8.3 6.1 6.8 7.6 th/mm.sup.3Red cell count 7.10 9.10 8.3 8.0 8.7 mil/mm.sup.3Hemoglobin 12.0 15.1 13.9 13.4 14.7 g/dlHematocrit 31.1 L* 40.9 37.1 36.2 39.7 %Platelet count 210 H 160 160 170 170 th/mm.sup.3Glucose 54 L 80 89 94 84 mg/dlBlood urea nitrogen 24 23 22 24 23 mg/dlCreatinine 1.6 1.5 1.6 1.5 1.6 mg/dlSodium 143 140 137 143 142 meq/dlPotassium 2.8 3.6 3.7 4.0 3.8 meq/dlCalcium 12.6 12.4 12.1 12.0 11.6 mg/dlPhosphorus 4.4 4.2 3.4 4.0 3.8 mg/dlTotal protein 6.0 6.0 6.1 6.0 6.6 g/dlAlbumin 3.5 3.3 3.5 3.6 3.8 g/dlGlobulin 2.5 2.7 2.6 2.4 2.8 g/dlBilirubin total 2.6 2.5 2.9 2.6 3.1 mg/dlAlbumin/Globulin ratio 1.4 1.2 1.3 1.5 1.4Calculated osmolality 283 280 275 287 284Chloride 99 101 101 107 103 meq/lCarbon dioxide 26 24 24 23 26 meq/lAnion gap 18 H 15 12 13 13Cholesterol 102 128 127 137 H 124 mg/dlProtein ElectrophoresisAlbumin 3.30 3.30 3.60 3.40 3.80 g/dlAlpha-1 Globulin 0.03 L 0.10 H 0.30 H 0.20 H 0.10 H g/dlAlpha-2 Globulin 0.50 0.40 0.10 L 0.10 L 0.40 g/dlBeta-1 Globulin 0.30 L 0.50 0.40 0.40 0.60 g/dlBeta-2 Globulin 0.50 0.30 0.50 0.50 0.30 g/dlGamma Globulin 1.20 1.40 1.20 1.20 1.20 g/dl__________________________________________________________________________ *L Lower than normal value H Higher than normal value
These results demonstrate the safety of long-term administration of this invention at a dosage regimen to produce maximum therapeutic effect. It is also evident that the hematological and biochemical levels obtained prior to the administration of this invention progressively increase with continuous feeding into a normal equine hematological and biochemical profile, even though some of the initial values are outside the normal physiological range. From this sampling, it is logical to conclude that cumulative toxic effects attributable to the long-term daily intake of the above defined composition, and consumed at the indicated dosage regimen, are non-existent and physiologically unapparent.
The protein electrophoretic values in the plasma from the serial blood samples illustrate that the albumin level markedly increases with the start of competitive racing. With the start of daily feeding of this invention, both the alpha-1 and beta-1 globulin fractions are increased to normal physiological values. Long-term feeding of this invention substantially increases the alpha-1 globulin fraction while the alpha-2 globulin fraction at first declines to a lower than normal physiological value and then rises to a normal physiological level. The beta-1, beta-2 and gamma fractions remain within their respective normal physiological range throughout the 282 day test even though the animal was continuously raced during this test.
The obvious visible signs of EIPH have not occurred in the test animal during either the many training sessions or the official races run in the current race meet while ingesting this invention admixed into the daily feed ration.
An unexpected discovery has been made from these results. It specifically appears that even with the relatively high levels of dietary crude protein (12 to 14 percent) present in the ration of racing horses, the level of nitrogen retention is significantly enhanced by gu microflora utilizing the NPN contained in this invention. Urea is largely excreted by the kidney into the urine before any recycling can occur. However, some urea recycling occurs into the large intestine and cecum where it is hydrolyzed into ammonia (NH 3 ) and carbon dioxide (CO 2 ) by urease enzyme, a product of plant and bacterial origin. The NH 3 is then utilized by the intestinal and cecal microflora for the synthesis of protein. Cecal microbial protein is hydrolyzed to yield amino acids (both essential and non-essential amino acids which may be lacking in the diet) which are then absorbed into the blood plasma where they can be utilized by the liver for synthesis of protein. This specifically appears to be what is occurring when the abnormal hematological and biochemical values of this test animal are normalized and improved with the daily intake of this invention even while continuously racing.
The invention is therefore not only useful in the prevention or elimination of EIPH. But when this invention is fed daily to racing or maximally exercising horses, there is a simultaneous normalization of hematological and biochemistry values and a substantially marked improvement in the speed, stamina and performance of the animal.
Another unexpected discovery following from the results obtained above was that since proteins are the only dissolved substances in the plasma that do not readily diffuse into the interstitial fluid, and only those substances that fail to pass through the pores of a semi-permeable membrane exert osmotic pressure, it is the dissolved proteins of the plasma and interstitial fluids that are responsible for the osmotic pressure at the capillary membrane. Thus colloid osmotic pressure of the plasma is caused by the dissolved proteins and since the concentration of dissolved plasma proteins substantially increases with the daily consumption of this invention, there develops simultaneously a significantly effective physiological elevation of the plasma colloid osmotic pressure.
The Donnan effect of the plasma proteins causes the osmotic pressure to be about 50 percent greater than that caused by proteins alone. This results from the fact that the protein molecules themselves cannot readily diffuse through the semi-permeable capillary membrane and the electronegative charges on the proteins, which are negative ions, attract positive ions (cations), mostly sodium ions but also include all the other cations in the extracellular fluid, and thus balance those charges. Osmotic pressure is determined by the numbers of particles per unit volume of fluid, not the weight of the particles. Those extra cations increase the number of osmotically active substances wherever the dissolved proteins occur and thus increase the total colloid osmotic pressure. Thus the Donnan equilibrium effect becomes more significant the higher the concentration of proteins, therefore justifying the requisite daily intake of NaCl to provide a racing or near maximally exercising horse about 1500 mEq Na + , and the daily intake of KCl to provide about 6400 mEq of K + and MgO to provide about 3300 mEq Mg 2+ and about 4200 mEq urea when this invention is consumed daily at a dosage regimen sufficient to produce maximum therapeutic effect and thus effectively provision for the prevention or elimination of EIPH.
EXAMPLE 5
This example illustrates the effectiveness of the daily oral administration of powdered urea--KCl--MgO formulation to a 9 year old Standardbred gelding, 480 kg body weight, with a long documented history of EIPH occurring during racing. Prior to each race, an intravenous bleeder injection was administered and no evidence of EIPH occurred until what was the animal's last race of the spring race meet. During that last race, an obvious aberration of the animal's usual performance became evident. Between 45 and 60 minutes postrace, an endoscopic examination was performed and a positive diagnosis made of EIPH with the presence of copious amounts of free-flowing blood in the bronchi and trachea. Further verification of the EIPH episode was documented several days later by a tracheobronchial wash which was cytologically examined and the presence observed of a predominance of macrophages which often contain hemosiderin, i.e. said erophages, hemosiderophages, thus confirming with absolute certainty the presence of a previous EIPH episode in this animal which occurred during racing. Subsequently, the animal was removed from the race track and rested for five months. Upon returning to training, in anticipation of racing, the daily feed intake consisted of about 14 pounds (6.4 kg) of alfalfa hay, about 8 pounds (3.6 kg) of whole oats and about 8 pounds (3.6 kg) of commercial mixed grain plus supplemental NaCl and a mineral-vitamin mixture. The powdered preparation of urea--KCl--MgO was added to the daily grain ration at a level of about 2.5 weight percent of urea, about 1.5 weight percent of KCl and about 0.1 weight percent of MgO. At this level of feed intake, the test animal was provided with a total daily intake of about 3,000 mEq of urea and about 6400 mEq K + . NaCl was supplemented to provide the test animal with a total daily intake of about 1550 mEq Na + .
The effective daily dosage administered of this invention was between about 320 mg/kg body weight and about 380 mg/kg body weight for urea, for KCl was between about 185 mg/kg body weight and about 250 mg/kg body weight and for MgO was between about 6 mg/kg body weight and about 7 mg/kg body weight. The dosage regimen employed during this test was sufficient to ensure maximum therapeutic response for the prevention or elimination of EIPH in racing or maximally exercising horses.
To ascertain if any pathophysiological alterations occurred during the test and became apparent in the hemogram and biochemical profile of the test animal, a series of blood samples were collected: (1) post-rest/pre-training (Day 0); (2) mid-training (Day 49); (3) post qualification race (Day 137); (4) training following qualification race (Day 178). The results are listed below.
__________________________________________________________________________ Blood Sample 1 2 3 4 Day 0 Day 49 Day 137 Day 178 Units__________________________________________________________________________Hematology andBiochemistryWhite cell count 9.7 8.0 7.8 7.6 th/mm.sup.3Red cell count 8.0 6.9 7.3 8.3 mil/mm.sup.3Hemoglobin 14.2 11.9 13.2 13.7 g/dlHematocrit 37.6 32.7 35.2 37.6 %Platelet count 200 170 190 190 th/mm.sup.3Glucose 94 114 H 85 84 mg/dlBlood urea nitrogen 28 H* 27 H 25 24 mg/dlCreatinine 1.5 1.6 1.7 1.6 mg/dlSodium 139 141 140 141 meq/dlPotassium 3.8 3.9 3.7 3.9 meq/dlCalcium 12.4 11.7 11.2 11.8 mg/dlPhosphorus 2.8 L 3.9 3.1 3.2 mg/dlTotal protein 7.0 6.6 7.5 7.5 g/dlAlbumin 3.3 3.2 3.3 3.5 g/dlGlobulin 3.7 3.4 4.2 H 4.0 H g/dlBilirubin total 1.2 1.5 3.0 2.7 mg/dlAlbumin/Globulin ratio 0.9 0.9 0.8 0.9Calculated osmolality 281 285 281 282Chloride 101 105 102 103 meq/lCarbon dioxide 28 25 26 26 meq/lAnion gap 10 11 12 12Cholesterol 88 85 89 90 mg/dlProtein ElectrophoresisAlbumin 3.00 2.80 3.50 3.50 g/dlAlpha-1 Globulin 0.03 L 0.20 H 0.10 H 0.10 H g/dlAlpha-2 Globulin 0.80 0.20 L 0.50 0.40 g/dlBeta-1 Globulin 0.60 0.60 0.70 0.60 g/dlBeta-2 Globulin 0.50 0.70 0.60 0.50 g/dlGamma Globulin 2.10 H 2.50 H 2.10 H 2.30 H g/dl__________________________________________________________________________ *L Lower than normal value H Higher than normal value
On Day 0, the hemogram and biochemistry values obtained were essentially normal for a rested horse entering race training. The exception to the essentially normal profile was the markedly elevated globulin portion of the total protein. Plasma protein electrophoresis revealed, surprisingly, even after five months of pasture rest, that the alpha-1 globulin fraction was of a lower than normal value which was comparable to the value found in some horses at the finish of a multi-race meet. Even more surprising was the obvious grossly above normal elevation of the gamma globulin fraction of the plama protein with a complete absence of any abnormal clinical or physical signs. Upon reviewing these electrophoretic results, the clinical pathological diagnosis of this data was polyclonal gammopathy.
Midway through the race training period (Day 49), the hematological and biochemical values were determined from the second blood sample. The values obtained were slightly lower than found in the first blood sample (Day 0) but were essentially normal except for the still large above normal elevation of the globulin portion of the plasma protein. Electrophoretic fractionation of the plasma protein of this blood sample revealed an elevated and a diminished concentration of the alpha-1 and alpha-2 globulin fractions, respectively. This phenomena has previously been observed to occur when this invention was consumed daily at a level sufficient to produce maximum therapeutic response for the prevention or elimination of EIPH in racing or maximally exercising horses. The gamma globulin fraction of the plasma protein was still grossly elevated, and thus the clinicopathological diagnosis was made again of polyclonal gammopathy.
Two days after an attempted qualifying race, when an unacceptable time of 2:13 for the mile was attained, a third blood sample (Day 137) was collected for hematological and biochemistry analysis. Again, with the exception of the globulin fraction of the plasma protein, the hemogram and remaining biochemical values were within normal limits. Electrophoretic analysis revealed the usual increase in albumin concentration which occurs after the initiation of competitive racing. The alpha-1 globulin fraction, although decreased in concentration from sample two (Day 49), was still elevated above normal level, but the concentration recorded was comparable to that occurring in the long-term daily feeding of a racing test animal. The alpha-2 globulin level, previously a lower than normal value, had now increased to a concentration within the normal range. The gamma globulin fraction was still elevated prominently to a higher than normal value, thus eliciting the continual clinicopathological diagnosis of polyclonal gammopathy.
The fourth blood sample (Day 178) was collected 41 days after the unsuccessful qualifying race and after much more endurance training and eight race-works. With the exception of the increased globulin concentration of the plasma protein, the remainder of the hemogram and biochemical values in this blood sample were within the normal range. Plasma protein electrophoresis revealed, as previously recorded in sample 3 (Day 137), an increased alpha-1 globulin, a normal concentration of alpha-2, beta-1 and beta-2 globulin fractions resulting in the repetitive clinicopathological diagnosis of polyclonal gammopathy.
At no time during the entire 187 day test period did the test animal show any hesitation or refusal to consume this invention when it was admixed into the daily grain ration. Nor was there ever any clinical indication evident of gastrointestinal upset or symptoms of physical discomfort or colic that could be attributed to the daily consumption of this invention.
About 45 minutes after completion of the unsuccessful qualifying race, which the test animal completed with a speed of about 726 meters per minute, an endoscopic examination of the lungs was performed by the official racetrack veterinarian to determine if the presence of EIPH was the primary factor influencing the slow racing time attained. The numerical classification of the performed endoscopic examination was Grade 0--no blood present. The test animal avidly consumed water when it was offered after completion of the qualifying race. As this example particularly illustrates, especially with the absence of endoscopic documentation of the most common presenting signs of EIPH, it is manifestly logical to conclude that other abnormal physiological factors are primarily responsible for causally influencing the resulting slow race time performed by the test animal.
Following the unsuccessful qualifying race, in which the test animal failed to reach a minimum speed of 754 meters per minute, the said animal was further endurance trained and race-worked eight times in the following 41 days. A racework consists of a warm-up mile at a speed of about 644 meters per minute, followed by a 30 minute rest and then an all-outspeed mile. In all eight of the all-out-speed miles, the minimum qualifying speed for racing of about 754 meters per minute was not reached, the speed produced ranged between about 695 meters per minute and about 721 meters per minute. However, at no time during or following these eight all-outspeed miles did the test animal show any characteristic symptoms of EIPH, ie. swallowing, coughing or dyspnea, and it always readily consumed water when offered after these raceworks.
From these results, it specifically appears and is logical to conclude that the daily oral administration of this invention at the aforementioned dosage regimen to a 9 year old Standardbred gelding, having a long documented history of EIPH occurring while racing and a currently ongoing clinical pathological diagnosis of polyclonal gammopathy, produces the anticipated maximum therapeutic response which is to effectively prevent or eliminate EIPH in racing or maximally exercising horses.
EXAMPLE 6
Racing or maximally exercising horses generally consume a total daily feed ration comprised of about 12 to 14 percent crude protein which is acknowledged as being an adequate and acceptable level of protein intake. Even with this level of protein in the ration the globulin fraction of the plasma proteins is surely and irrevocably reduced with continuous racing of the said animals during the course of a long multi-race meet.
A surprising discovery is that the levels of both the albumin and globulin fractions of the plasma protein are substantially increased when this invention is administered daily to racing horses at a dosage regimen sufficient to produce maximum therapeutic response for the prevention or elimination of EIPH. The quantity of feed nitrogen utilization and retention is significantly enhanced by intestinal microflora utilizing the NPN, ie. urea, present in this invention.
The albumin and globulin fractions of plasma protein were determined through the laboratory technique of protein electrophoresis and the results listed below for each blood sample collected. Single blood samples were obtained from a 4 year old Standardbred and an 8 year old Thoroughbred following completion of their respective six-months long race meets and consuming the usual type of diet fed to racing horses. For comparison, a series of blood samples were procured from a 3 year old Standardbred at various times during an ongoing multi-race meet while consuming this invention supplemented into the usual type of ration fed to a racing horse: (1) post-training and pre-racing (Day 0); (2) early racing (Day 30); (3) mid-racing (Day 72); and, (4) late mid-racing (Day 107).
__________________________________________________________________________ Standardbred-Racing LateProtein Standardbred Thoroughbred Pre-Race Early Race Mid-race Mid-RaceElectrophoresis Post-race Meet Post race Meet Day 0 Day 30 Day 72 Day 107 Units__________________________________________________________________________Albumin 3.70 3.60 3.30 3.60 3.40 3.80 g/dlAlpha-1 Globulin 0.03 L* 0.10 H 0.10 H 0.30 H 0.20 H 0.10 H g/dlAlpha-2 Globulin 0.50 0.40 0.40 0.10 L 0.10 L 0.40 g/dlBeta-1 Globulin 0.30 L 0.30 L 0.50 0.40 0.40 0.60 g/dlBeta-2 Globulin 0.50 0.30 0.30 0.50 0.60 0.30 g/dlGamma Globulin 1.20 1.10 1.40 1.20 1.20 1.20 g/dl__________________________________________________________________________ *L Lower than normal value H Higher than normal value
The rate of synthesis of plasma protein by the liver depends on the concentration of amino acid in the blood. Consequently, the concentration of proteins becomes reduced whenever an appropriate supply of amino acid is not available. Conversely, when excess proteins are available in the plasma but insufficient proteins are available in the cells, the plasma proteins are used to form tissue cells. Undoubtedly, this is the sequence that is occurring when the plasma protein level is measured in horses that are continuously raced and consume a normal performance-type feed ration. Essentially, all the albumin of the plasma proteins, as well as 60 to 80 percent of the globulins, are formed in the liver. The remainder of the globulins, mainly the gamma globulins which constitute the antibodies, are formed in the lymphoid tissue and other cells of the reticuloendothelial system. The principal function of albumin is to provide colloid osmotic pressure which prevents plasma loss from capillaries. The globulins also perform a number of enzymatic functions in the plasma but principally they are responsible for the natural and acquired immunity against invading organisms.
Regardless of the diet available, the albumin content of plasma protein is firstly and sizeably increased when a horse begins continuous racing. Unless excess amino acids become available from the diet, the globulin fraction of plasma protein, with the exception of the immunogenic gamma globulin fraction, found in racing horses is substantially reduced with continuous racing.
Even though the colloid osmotic pressure of the plasma is a weak osmotic force, it plays an exceedingly important role in the maintenance of normal blood and interstitial fluid volumes. Since 1 gram of albumin contains twice as many molecules as 1 gram of globulin, each gram of albumin exerts twice as much osmotic pressure as each gram of globulin. Since there is almost 50 percent more albumin than globulin, about 60 percent of the total osmotic pressure of the plasma in racing horses results from the albumin fraction and about 40 percent from the globulins. Capillary hemodynamics in non-racing horses are mainly influenced by albumin. However, a further discovery is that in racing horses the globulins, and primarily the alpha-1 globulin fraction, substantially effect the total colloid osmotic pressure of the plasma. The alpha-1 globulin level is increased between about 3 to about 10 times more in continuously racing horses consuming this invention daily than the level found in continuously racing horses not consuming this invention.
With the daily intake of this invention administered at maximum therapeutic dosage to prevent or eliminate EIPH the globulin fraction of the plasma proteins becomes substantially increased in racing horses. The concentration of the alpha-1 globulin fraction especially becomes increased many times more than the other globulin fractions. The colloid osmotic pressure exerted by alpha-1 globulin at every plasma protein concentration is more than twice that produced by the same plasma protein concentration of albumin, thus positively influencing the non-appearance of EIPH and the markedly improved performance of racing or maximally exercising horses supplemented daily with this invention.
EXAMPLE 7
This example illustrates the preparation and utilization of specialized forms of this invention that can be alternately and adjunctly used for the prevention or elimination of EIPH in racing or maximally exercising horses. The test was conducted to demonstrate that various physical forms of this invention produce identical observable physiological effects, ie. increased water intake and increased urine excretion, as observed in the safest and most practical methods of administration, namely, as dry formulations or aqueous solutions added to the daily feed ration and voluntarily consumed by the horse.
Hard capsules were prepared from the following formulation:
225 g of urea
160 g of potassium chloride
The above ingredients were thoroughly mixed with each other and the mixture was filled into gelatin capsules. Each capsule contained about 28.6 g of the composition and thus about 16.6 g of urea, about 11.8 g of KCl and about 800 mEq Mg 2+ . The capsules were administered on a daily basis to horses.
Tablets were prepared from the following formulation:
225 g of urea
160 g of potassium chloride
5 g of magnesium stearate
The active ingredients were thoroughly mixed with magnesium stearate and compressed into tablets, each weighing about 100 g and containing about 58 g of urea and about 41 g of KCl. The tablets were considered suitable for administration to horses.
Compositions defined above are readily absorbed into the bloodstream after reaching the stomach and intestine when given orally. The objects provide an alternate or adjunct method of prophylactic or curative treatment of EIPH in racing or maximally exercising horses.
A series of tests were performed on each of two horses, one a 4 year old Thoroughbred gelding, 431 kg body weight, the other a 4 year old Standardbred gelding, 428 kg body weight, using the above formulations and documenting the resulting observable physiological effects. Each test period duration was seven days with a recovery period of the same length of time.
During the two tests, the Thoroughbred animal received an effective daily dosage of urea of between about 475 mg/kg body weight to about 535 mg/kg body weight and between about 225 mg/kg body weight and about 380 mg/kg body weight of KCl, while the Standardbred was given about 485 mg/kg body weight and about 540 mg/kg body weight of urea and between about 230 mg/kg body weight and about 385 mg/kg body weight of KCl. Each test animal received supplemental NaCl to provide a total daily intake of about 1400 mEq Na + . The total daily feed intake along with the administration of the specialized forms of this invention provided each test animal with a daily intake of about 3800 mEq of urea and about 6300 mEq of K + . The animal's daily feed provided a total daily intake of about 900 mEq of Mg 2+ .
In both test animals, during these tests, noticeable physiological effects, ie. increased water intake and increased urine excretion, occurred when the tablets and hard capsules were given orally. By the second day after the start of oral administration of these formulations, the physiological effects became noticeably elevated and remained at that level until the third day after completion of the tests, at which time, both water intake and urine excretion decreased to pre-test levels.
The two test horses did not react adversely to the oral administration of the specialized forms of this invention. No evidence of colic or gastrointestinal upset occurred in these horses during these tests.
It is evident from this example that regardless of the physical form of this invention, the occurrence of noticeable physiological effects, after oral administration, were identical whether the horse was racing, maximally exercising or in a maintenance condition. It thus follows that the etiopathogenesis of EIPH in racing or maximally exercising horses could also be prophylactically or curatively treated by oral administration of specialized forms of this invention.
While I have described and given examples of preferred embodiments of my invention, it will be apparent to those skilled in the art that changes and modifications may be made without departing from my invention in its broader aspects. I therefore intend the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention. | A method and composition for the preventive and curative treatment of exercise-induced pulmonary hemorrhage in animals. The method comprises administration to the animal of a mixture of urea, alkaline potassium salts and magnesium salts. The composition comprises a mixture of urea, alkaline potassium salts, and magnesium salts, and if required, a pharmaceutically acceptable carrier. | 0 |
BACKGROUND
Droplet ejection devices are used for depositing droplets on a substrate. Ink jet printers are a type of droplet ejection device. Ink jet printers typically include an ink supply to a nozzle path. The nozzle path terminates in a nozzle opening from which ink drops are ejected. Ink drop ejection is controlled by pressurizing ink in the ink path with an actuator, which may be, for example, a piezoelectric deflector, a thermal bubble jet generator, or an electro statically deflected element. A typical printhead has an array of ink paths with corresponding nozzle openings and associated actuators, such that drop ejection from each nozzle opening can be independently controlled. In a drop-on-demand printhead, each actuator is fired to selectively eject a drop at a specific pixel location of an image as the printhead and a printing substrate are moved relative to one another. In high performance printheads, the nozzle openings typically have a diameter of 50 microns or less, e.g. around 35 microns, are separated at a pitch of 100-300 nozzle/inch, have a resolution of 100 to 3000 dpi or more, and provide drop sizes of about 1 to 70 picoliters or less. Drop ejection frequency can be 10 kHz or more.
Printing accuracy is influenced by a number of factors, including the size and velocity uniformity of drops ejected by the nozzles in the head and among multiple heads in a printer. The drop size and drop velocity uniformity are in turn influenced by factors such as the dimensional uniformity of the ink paths, acoustic interference effects, contamination in the ink flow paths, and the actuation uniformity of the actuators.
SUMMARY
In general, in an aspect, a printhead includes a body; an actuator attached to the body, and an enclosed space between the actuator and the body forms a chamber; an opening defined by the body for releasing pressure in the chamber; and a seal attached to the opening to seal the chamber while permitting pressure to be released.
Implementation can include one or more of the following features. The actuator can include a piezoelectric material, and the seal can be made of plastic (e.g., polyimide). The printhead can include a laminate subassembly, the actuator can be attached to the laminate subassembly, and the laminate subassembly can include a flex print, cavity plate, descender plate, acoustic dampener, spacer, and an orifice plate. Openings can be formed in the acoustic dampener, and channels can be formed in the descender plate. The printhead can include an ink manifold defined by the body. The seal can be attached to the opening using a detachable adhesive.
In another aspect, a flexible circuit includes a body made of a flexible material, electrical traces formed on the body, and openings defined by the body for fluid to pass through.
Implementations can include one or more of the following features. The body can be made of a polyimide, or can include two layers of a flexible material (e.g., polyimide) that are bonded together (e.g., with an adhesive that can include polyimide). The body can include a base layer (e.g., polyimide material), the electrical traces being formed on the base layer, and a coverlay (e.g., printable polyimide) covering the electrical traces.
In yet another aspect, a laminate subassembly includes a plurality of laminates, including an actuator, cavity plate, descender plate, and orifice plate, each laminate having openings, the openings in each laminate align with the openings in the other laminates, and inspection of the openings ensures alignment and placement of the laminates.
Implementations can include one or more of the following features. The laminate subassembly can further include a fiducial mark on the actuator, such that the fiducial mark is visible when the laminates are aligned. The plurality of laminates can also include an acoustic dampener, flexible circuit, and a spacer.
In an aspect, a method of aligning laminates includes providing a plurality of laminates with openings, including an actuator, cavity plate, descender plate, and orifice plate, one of the laminates includes a fiducial mark; aligning the laminates using the openings in the laminates and the fiducial mark on one of the laminates; attaching the laminates together; and inspecting the openings to determine alignment of the laminates. Inspecting the openings can include using a camera to look through the openings in the laminates to verify that the fiducial mark is aligned with the openings.
Further aspects, features, and advantages will become apparent from the following detailed description, the drawings, and the claims.
DESCRIPTION OF DRAWINGS
FIG. 1A is a perspective view of a printhead.
FIG. 1B is an exploded view of a printhead.
FIG. 2A is a perspective view of a body and laminate subassembly of a printhead.
FIG. 2B is a cross-sectional view of the printhead.
FIG. 2C is a perspective view of the bottom side of the body.
FIG. 3 is an exploded view of the laminate subassembly.
FIG. 4A is a perspective view of the flex print.
FIG. 4B is a cross-sectional view of the flex print.
DETAILED DESCRIPTION
Referring to FIGS. 1A and 1B , a printhead 10 includes a body 12 bonded to a laminate subassembly 14 . The parts can be bonded together with an adhesive, such as an epoxy. Ink is first introduced to the printhead 10 through the filter 16 and tube 18 and into the body 12 via an ink barb 20 formed in the body 12 . An opening 22 is formed in the body 12 to release air pressure between the body 12 and subassembly 14 ; a seal 24 is placed over the opening 22 . A cover 26 is attached to the top of the body 12 .
FIGS. 2A and 2B show the body 12 and the subassembly 14 of the printhead 10 . The first layer in the subassembly 14 is a piezoelectric element 28 , which is bonded to a flex print 30 . When the body 12 is bonded to the subassembly 14 , a chamber 32 is formed to protect the piezoelectric element 28 from the environment and to seal it from the ink flow path.
Referring to FIG. 3 , the subassembly 14 includes the following parts bonded together, a piezoelectric element 28 , a flex print 30 , cavity plate 34 , descender plate 36 , acoustic dampener 38 , spacer 40 , and orifice plate 42 . The parts can be bonded together with an adhesive, such as an epoxy.
Referring to FIG. 2A , the ink travels down the ink barb 20 to the bottom side of the body 12 and into a fluid manifold 44 formed in the body 12 as shown in FIG. 2C . The ink fills the fluid manifold 44 and then travels through openings 46 in the flex print 30 and into the pumping chambers 48 formed in the cavity plate 34 as shown in FIG. 3 .
Referring to FIG. 3 , when the piezoelectric element 28 is actuated, the ink in the pumping chambers is pumped through openings 50 in the pumping chambers through openings 52 in the descender plate 36 through openings (not shown) in the acoustic dampener 38 through the spacer openings 54 and out the orifices 56 in the orifice plate 42 .
FIG. 2B shows a cross-sectional view of the chamber 32 formed when the body 12 is bonded to the subassembly 14 with the piezoelectric element 28 as the first layer in the subassembly 14 . The chamber 32 protects the piezoelectric element 28 from the external environment. An opening 22 is formed in the body 12 to release air pressure in the chamber 32 , and a seal 24 is bonded to the opening 22 with adhesive (i.e., epoxy). The seal 24 can be made of a compliant material (i.e., polyimide) that changes shape under pressure.
When the air pressure inside the chamber 32 rises, a force is applied around the perimeter of the opening 22 , where the seal 24 contacts the opening 22 . The amount of force applied to the seal 24 is a function of the radius of the opening 22 . At a certain pressure, the adhesive that bonds the seal 24 to the opening 22 can detach from the surface of the opening 22 to release air pressure, and subsequently reattach. The radius of the opening 22 and strength of the adhesive can be designed for specified air pressures, such that the adhesive detaches and reattaches at specified air pressures.
FIG. 2A shows the opening 22 in the body 12 raised above the surface of the body 12 . By raising the opening 22 , the piezoelectric element 28 is protected from ink leaks, and the seal 24 further protects the piezoelectric element 28 from ink or other environmental factors.
Referring to FIG. 3 , the openings in the flex print 30 provide an ink flow path from the manifold 44 to the pumping chambers. FIG. 4A shows a flex print 30 with electrical traces 58 running through the spaces between the openings to avoid contact with the fluid as it travels through the openings 46 . The electrical traces 58 run from electrodes near the center of the flex print 30 (next to the piezoelectric element) to the connectors 60 at the ends of the flex print 30 . Tabs 62 extend on either side of the connectors 60 , which snap into the cover 26 as shown in FIG. 1A .
FIG. 4B shows a flex print 30 with a first layer 64 and second layer 66 bonded together with an adhesive. Over time ink can separate the adhesive from the two layers and leak inside the flex print 30 and contact the electrical traces 58 . In an implementation, the two layers of the flex print 30 are made of a polyimide and the adhesive also contains polyimide. The ink is less likely to separate the adhesive from the two layers when the layers of the flex print 30 and adhesive are made of the same material. The openings in the flex print 30 can be cut with a die, laser, or other similar methods. Coatings or other materials can be used to protect the edges of the openings in the flex print 30 from degradation by fluids passing through them.
Referring to FIG. 3 , while the openings in the flex print 30 provide an ink flow path to the pumping chambers, only some of the openings actually line up with the pumping chambers in the cavity plate 34 . The remaining pumping chambers are blocked by the spaces between the openings. For ink to reach the blocked pumping chambers, the ink travels through the openings in the flex print 30 through the unblocked pumping chambers and into channels 68 in the descender plate 36 . The ink in these channels 68 then travels back up into the cavity plate 34 into the blocked pumping chambers.
Referring to FIG. 3 , if the acoustic dampener 38 is made of a plastic material, such as Upilex® polyimide, the material may not bond evenly, which could leave an area of the material unbonded. For a better bond, openings 70 can be cut out of the acoustic dampener 38 .
The body 12 can be made of a plastic material, such as polyphenylene sulfide (PPS), or metal, such as aluminum. The cover 26 can be made of metal or a plastic material, such as Delrin® acetal. The flex print 30 and acoustic dampener 38 can be made of Upilex® polyimide, while the descender plate 36 and cavity plate 34 can be made of a metal, such as Kovar® metal alloy. The spacer 40 can be made of material with a low modulus, such as carbon (about 7 MPa) or polyimide (about 3 MPa). The orifice plate 42 can be made of stainless steel.
The spacer 40 can be used to bond the orifice plate 42 and acoustic dampener 38 within the laminate subassembly 14 . Rather than directly apply adhesive to the orifice plate 42 or acoustic dampener 38 , adhesive can be directly applied on both sides of the spacer and the orifice plate 42 and acoustic dampener 38 can then be bonded to the spacer. The spacer can also distribute the strain between laminates with different thermal coefficients of expansion. For example, laminates with different thermal coefficients of expansion bonded together at a bonding temperature of about 150° C. can bow as the laminates cool to room temperature (about 22° C.). The spacer can reduce bowing in the laminate subassembly by distributing the bond strain. The thickness of the spacer and its modulus can affect its ability to distribute strain within the subassembly. The percent strain of the spacer is a function of the strain divided by the thickness of the spacer. FIG. 2C depicts the body 12 with three holes 72 , two on one side of the body 12 and one on the other side, for receiving three eccentric screws to secure the printhead 10 to a rack assembly.
Referring to FIG. 3 , openings 74 on the ends of each part are used to check for missing parts and alignment of the parts. An inspection camera looks into the openings 74 to visually inspect the alignment of the parts. A fiducial mark is placed on the piezoelectric element 28 and can be seen when all the parts are properly aligned. Additionally, after production or during maintenance of a printhead 10 , a visual inspection through the openings 74 ensures that all the parts are present and that the parts are in the correct order.
In other implementations, the body and laminate subassembly can be attached by other securing devices, such as adhesives, screws, and clasps. The parts of the subassembly can be secured by other materials or adhesives. The seal 24 can be attached to the opening in the body by other adhesives. Referring to FIGS. 2A and 2B , rather than forming a chamber between the subassembly and the body to protect the piezoelectric element, the piezoelectric element could be protected by a coating. While FIG. 1A shows the tabs 62 snapping into the cover 26 of the printhead 10 , the tabs could be secured to a printhead by screws, clasps, adhesive, or other fasteners. The flex print 30 in FIG. 3 shows several openings on both sides of the flex print 30 , however, the flex print 30 can have only one opening for an ink passage or openings on just one side. Similarly, the cavity plate in FIG. 3 shows several pumping chambers on both sides of the cavity plate, but the cavity plate can have only one pumping chamber or pumping chambers on only one side.
The connectors 60 in FIG. 1A can be directly secured to the cover 26 without using the tabs 62 . For example, the connectors 60 could be glued to the cover 26 using an adhesive.
Referring to FIG. 4A , the electrical traces 58 on flex print 30 can be sealed to prevent fluid flowing through openings 46 from contacting the traces. For example, a first layer 64 in FIG. 4B can be a polyimide material (i.e., Upilex® polyimide), the electrical traces can be formed on the first layer 64 , and a second layer 66 can be a coverlay that covers the electrical traces. The coverlay can be a printable polyimide, such as Espanex® SPI screen printable polyimide coverlay available from Nippon Steel Chemical, Japan. The polyimide can be deposited using a silk screen printing method or other deposition methods.
Referring to FIG. 1A , the dimensions of the printhead 10 can include a height of about 29.15 mm, a length of about 115.9 mm, and a width of about 30.6 mm. Referring to FIG. 3 , the laminate subassembly 14 can also include a ground plate 41 that can include a tab 43 . When the laminates are stacked together, the tab 43 extends from the subassembly 14 as seen in FIG. 2A and can be folded over the housing 12 . The ground wire 13 in FIG. 1 connects to the tab 43 of ground plate 41 .
Referring to FIG. 3 , the laminate subassembly 14 can also include a ground plate 41 that can include a tab 43 . When the laminates are stacked together, the tab 43 extends from the subassembly 14 as seen in FIG. 2A and can be folded over the housing 12 . The ground wire 13 in FIG. 1 connects to the tab 43 of ground plate 41 .
Referring again to FIG. 3 , the fluid flowing through the laminate subassembly 14 can pass through openings 54 in the ground plate 41 and out the orifices 56 in the orifice plate 42 . The ground plate 41 can also have openings 74 that align with the openings 74 of the other laminates in subassembly 14 .
Other implementations are within the scope of the following claims. | A printhead including a body; an actuator attached to the body, and an enclosed space between the actuator and the body forms a chamber; an opening defined by the body for releasing pressure in the chamber; and a seal attached to the opening to seal the chamber while permitting pressure to be released. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. Ser. No. 12/992,326, filed Dec. 30, 2010, now U.S. Pat. No. 8,609,570, issued Dec. 17, 2013, which is a U.S. National Stage filing under 35 U.S.C. section 371 of International Application No. PCT/EP2009/003333, filed May 11, 2009, which in turn claims priority to German Patent Application No. 10 2008 023 472.9, filed May 14, 2008.
FIELD OF THE INVENTION
The present invention relates to a supported platinum catalyst.
BACKGROUND OF THE INVENTION
Supported noble metal catalysts, in which relatively small noble metal particles are deposited on the surface of a solid support, are used in particular in synthetic chemical and petrochemical processes in order to convert a wide variety of educts into desired intermediate products or end products or to chemically refine different cuts of petroleum processing. In addition, supported noble metal catalysts are in particular also used as oxidation catalysts in the purification of exhaust gases from combustion engines.
Supported catalysts loaded with noble metal are normally produced by means of a multi-stage method. For example, in a first step a support material is impregnated with a noble metal salt solution of the desired noble metal. After the removal of the solvent from the support material in a subsequent step, the support material is then calcined in a further step, wherein the noble metal can be converted to an oxide form by thermal treatment. Then, in a further step, the noble metal component is converted to the catalytically active, highly dispersed noble metal of oxidation state 0, for example by means of hydrogen, carbon monoxide or wet-chemical reducing agent. The supported noble metal catalyst can be stabilized for storage purposes in a final step, for example by wet stabilization by means of an oil or by dry stabilization by means of preoxidation (passivation) of the deposited noble metal particles.
The activity of supported noble metal catalysts normally depends on the size of the noble metal particles. The supported noble metal catalysts known in the state of the art have the disadvantage that they become less active in the course of their use because of a sintering of the noble metal particles into larger units accompanied by a reduction in catalytically active surface. The speed of this so-called thermal ageing process depends on the temperature level at which the catalyst is used. To be precise, as the operating temperature increases so does the speed of said ageing process, which is assumed to be caused by an increased mobility of the noble metal particles on the support material surface accompanied by an increased tendency to sinter.
A large number of attempts have already been made in the state of the art to produce catalysts which have a high activity when used at high temperatures and are subject to only a low thermal ageing process. Kubanek et al., “Microporous and Mesoporous Materials 77 (2005) 89-96”, for example describe the production of a supported platinum catalyst by impregnating a zeolite of the structure type MFI (SH27) with the Pt precursor compound Pt(NH 3 ) 4 (NO 3 ) 2 and then calcining the zeolite loaded with the precursor compound in a protective gas atmosphere. When Pt(NH 3 ) 4 (NO 3 ) 2 is used, autoreduction occurs at relatively high temperatures. However, the thus-produced supported platinum catalyst has a relatively low activity as well as a relatively high tendency to thermal ageing.
SUMMARY OF THE INVENTION
An object of the present invention is therefore to provide a method in particular for producing a platinum catalyst precursor, by means of which supported platinum catalysts can be produced which have an increased activity compared with the platinum catalysts known from the state of the art.
Furthermore, an object of the present invention is to provide a method for producing a platinum catalyst precursor, by means of which supported platinum catalysts can be produced which display a relatively low tendency to thermal ageing and accordingly maintain their catalytic activity almost unchanged over long service lives.
This object is achieved by a method comprising the steps of:
a) impregnating an open-pored support material with platinum sulphite acid; b) calcining the impregnated support material under a protective gas.
It was surprisingly discovered that, by means of the method according to the invention, a platinum catalyst precursor can be obtained which, after the conversion of the platinum component to the oxidation state 0, results in a supported platinum catalyst which is characterized by an increased activity.
In addition, it was surprisingly established that, by impregnating an open-pored support material with platinum sulphite acid and calcining the impregnated support material in a protective gas atmosphere, a platinum catalyst precursor can be obtained by means of which, by reduction of the platinum component into the oxidation state 0, a supported platinum catalyst can be produced which displays a very low tendency to thermal ageing at relatively high temperatures and maintains its catalytic activity largely unchanged over relatively long service lives.
These advantages of a platinum catalyst produced via the method according to the invention are brought to bear in particular during use at high temperatures, such as for example in oxidation catalysis in which corresponding platinum catalysts produced in conventional ways are prone to a rapid thermal ageing because of a high mobility of the platinum particles caused by the predominantly high temperatures accompanied by an increased tendency to sinter.
Platinum catalyst precursors and from these, following reduction, finally supported platinum catalysts can be produced by means of the method according to the invention, i.e. supported platinum catalysts which comprise Pt of oxidation state 0. The platinum catalysts can be both metal catalysts which, in addition to Pt of oxidation state 0, contain one or more additional transition metals of any oxidation state or of oxidation state 0, preferably noble metals, and pure platinum catalysts which contain only Pt of oxidation state 0 as catalytically active metal. If, in addition to Pt, a further transition metal of oxidation state 0 is also present in the platinum catalyst, the metals can be present in the form of particles of pure metal or in the form of alloy particles. To produce platinum catalysts which, in addition to Pt, also comprise at least one further transition metal of oxidation state 0, e.g. Ag, in the framework of the method according to the invention the open-pored support material can for example be impregnated with platinum sulphite acid and with a further corresponding transition metal compound before the metal components are converted to the oxidation state 0.
It is pointed out that the catalysts obtainable via the method according to the invention are not limited to catalysts in which only Pt is present as metal. It is also conceivable that, in addition to platinum, metal oxides that are difficult to reduce are also present.
In one step of the method according to the invention, the open-pored support material is impregnated with platinum sulphite acid. Platinum sulphite acid is known in the state of the art and is often called “PSA” there. Platinum sulphite acid is assigned the Chemical Abstract Number 61420-92-6 and is freely available on the market, for example from Heraeus, Hanau, Germany as 10.4% platinum sulphite acid solution.
In the method according to the invention, the platinum sulphite acid is preferably used in the form of an aqueous platinum sulphite acid solution containing 0.01 to 15 wt.-% Pt (metal). It is further preferred to use the platinum sulphite acid in the form of an aqueous platinum sulphite acid solution containing 0.1 to 8 wt.-% Pt (metal) in the method according to the invention, more preferably in the form of an aqueous platinum sulphite acid solution containing 1 to 6 wt.-% Pt (metal) and particularly preferably in the form of an aqueous platinum sulphite acid solution containing 2.5 to 3.5 wt.-% Pt (metal). It is most preferred to use the platinum sulphite acid in the form of an aqueous platinum sulphite acid solution containing 2.8 to 3.3 wt.-% Pt (metal) in the method according to the invention.
According to a preferred embodiment of the method according to the invention, the method furthermore comprises the step of: converting the platinum component of the calcined platinum sulphite acid to the oxidation state 0. The support material impregnated with platinum sulphite acid is subjected to a reducing step after the calcining. Where the method according to the invention comprises the above-named step of converting the platinum component of the calcined platinum sulphite acid to the oxidation state 0, the method according to the invention relates to a method for producing a supported platinum catalyst, wherein the platinum catalyst can comprise, in addition to Pt of oxidation state 0, one or more further transition metals, in particular noble metals, of oxidation state 0.
The platinum component of the calcined platinum sulphite acid can be converted to the oxidation state 0 both by wet-chemical route, i.e. by means of a solution with a reducing effect, and by dry-chemical route, i.e. by means of a gas with a reducing effect. It is preferred according to the invention that the platinum component of the calcined platinum sulphite acid is converted to the oxidation state 0 by dry-chemical route. As a result there is the possibility of carrying out the reduction in a procedurally simple way at relatively high temperatures, which promotes a rapid and complete reduction of the platinum component.
According to a further preferred embodiment of the method according to the invention, it is provided that the platinum component of the calcined platinum sulphite acid is converted to the oxidation state 0 at a temperature of at least 100° C. In this connection, it is preferred that the platinum component is reduced at a temperature of from 100° C. to 400° C., more preferably at a temperature of from 200° C. to 350° C., further preferably at a temperature of from 275° C. to 325° C. and particularly preferably at a temperature of 300° C.
As has already been stated above, it can be preferred according to the invention that the platinum component of the calcined platinum sulphite acid is converted to the oxidation state 0 by dry-chemical route. In principle any gaseous or gasifiable reducing agent can be used, by means of which the platinum component can be reduced, such as for example hydrogen, carbon monoxide, ethylene or methanol, ethanol, etc. According to a particularly preferred embodiment of the method according to the invention, it is provided that the platinum component of the calcined platinum sulphite acid is converted to the oxidation state 0 by means of hydrogen.
If hydrogen is used as reducing agent, it can be preferred that the hydrogen is diluted with an inert gas such as for example nitrogen or a noble gas such as helium, neon, argon, krypton and/or xenon, wherein nitrogen is particularly cost-efficient and is accordingly preferred according to the invention. For example, the conversion of the platinum component of the calcined platinum sulphite acid to the oxidation state 0 by reduction in an atmosphere consisting of 0.1 wt.-% to 100 wt.-% hydrogen, preferably 3 to 5 wt.-% hydrogen, and the remainder inert gas is preferred according to the invention.
For example, the conversion of the platinum component of the calcined platinum sulphite acid to the oxidation state 0 by reduction in an atmosphere consisting of 10 wt.-% to 60 wt.-% hydrogen, preferably 15 to 30 wt.-% hydrogen, and the remainder inert gas is furthermore preferred according to the invention.
In order to largely minimize the sulphur content of the platinum catalyst resulting from the method of the invention, it can be provided according to a further preferred embodiment of the method according to the invention that the steps of calcining the impregnated support material under protective gas and of converting the platinum component of the calcined platinum sulphite acid to the oxidation state 0 are carried out several times. For example, the two named method steps can each be carried out 2, 3, 4 or 5 times, wherein the platinum component is converted to the oxidation state 0 after every single calcining step.
It is further preferred within the meaning of the present invention that the reduction is carried out for a duration of at least 1 minute, preferably at least 30 minutes, further preferably at least 1 hour and most preferably of at least 3 hours, wherein a duration of 4 or 5 hours is most preferred.
Within the framework of the present invention, the open-pored support material can be impregnated with platinum sulphite acid in principle according to any method known to a person skilled in the art from the state of the art and considered to be suitable. Examples of methods that are preferred according to the invention are spraying a platinum sulphite acid solution onto the support material, dipping the support material into a platinum sulphite acid solution or the so-called incipient wetness method (pore-filling method), in which there is added to the support material a volume of solution corresponding to the volume of its pores.
If the platinum sulphite acid solution is to be applied by spraying the solution onto the support material, the spraying-on can be carried out according to the present invention by any spraying method known to a person skilled in the art from the state of the art.
If it is provided that the platinum sulphite acid solution is to be applied by dipping the support material into the solution, this is carried out by first dipping the support material into the platinum sulphite acid solution and then—for example by suction—removing from it solution not adhering to the support material surface.
It is particularly preferred according to the invention that the support material is impregnated with platinum sulphite acid by means of the incipient wetness method. In this method, the open-pored support material is loaded with a solution of the impregnating agent—here platinum sulphite acid, wherein the volume of the solution corresponds to the pore volume of the support material, which is why, after being loaded with the solution, the zeolite material is outwardly dry and with it pourable. The incipient wetness method is also known to a person skilled in the art by the name pore-filling method.
The open-pored support material of the present invention is any support material which is known to a person skilled in the art as suitable for the purpose according to the invention. The open-pored support material is preferably an inorganic open-pored support material.
It is further preferred that the open-pored support material is a support material with monomodal or with multimodal pore distribution.
According to a further preferred embodiment of the method according to the invention, the support material comprises a material selected from the group consisting of titanium oxide; γ-, θ- or Δ-aluminium oxide; cerium oxide; silicon oxide; zinc oxide; magnesium oxide; aluminium-silicon oxide; silicon carbide and magnesium silicate or a mixture of two or more of the above-named materials. It can furthermore be preferred that the support material consists of one of the above-named materials or mixtures.
According to a further preferred embodiment of the method according to the invention, it is provided that the support material is a zeolite material. By a zeolite material is meant within the framework of the present invention according to a definition of the International Mineralogical Association (D. S. Coombs et al., Can. Mineralogist, 35, 1997, 1571) a crystalline substance with a structure characterized by a framework of tetrahedra linked together. Each tetrahedron consists of four oxygen atoms which surround a central atom, wherein the framework contains open cavities in the form of channels and cages which are normally occupied by water molecules and extra-framework cations which can often be exchanged. The channels of the material are large enough to allow access to guest compounds. In the hydrated materials, the dehydration mostly occurs at temperatures below about 400° C. and is for the most part reversible.
According to a further preferred embodiment of the method according to the invention, it is provided that the zeolite material is a microporous or a mesoporous zeolite material. By the terms “microporous zeolite material” and “mesoporous zeolite material” are to be understood according to the classification of porous solids according to IUPAC (International Union of Pure and Applied Chemistry) zeolite materials the pores of which have a diameter of less than 2 nm and a diameter of from 2 nm to 50 nm respectively.
The zeolite material to be used in the method according to the invention can preferably correspond to one of the following structure types: ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AWO, AWW, BCT, BEA, BEC, BIK, BOG, BPH, BRE, CAN, CAS, CDO, CFI, CGF, CGS, CHA, CHI, CLO, CON, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EMT, EON, EPI, ERI, ESV, ETR, EUO, EZT, FAR, FAU, FER, FRA, GIS, GIU, GME, GON, GOO, HEU, IFR, IHW, ISV, ITE, ITH, ITW, IWR, IWV, IWW, JBW, KFI, LAU, LEV, LIO, LIT, LOS, LOV, LTA, LTL, LTN, MAR, MAZ, MEI, MEL, MEP, MER, MFI, MFS, MON, MOR, MOZ, MSE, MSO, MTF, MTN, MTT, MTW, MWW, NAB, NAT, NES, NON, NPO, NSI, OBW, OFF, OSI, OSO, OWE, PAR, PAU, PHI, PON, RHO, RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAO, SAS, SAT, SAV, SBE, SBS, SBT, SFE, SFF, SFG, SFH, SFN, SFO, SGT, SIV, SOD, SOS, SSY, STF, STI, STT, SZR, TER, THO, TON, TSC, TUN, UEI, UFI, UOZ, USI, UTL, VET, VFI, VNI, VSV, WEI, WEN, YUG and ZON, wherein zeolite materials of the structure type Beta (BEA) are particularly preferred. The above nomenclature of three-letter codes corresponds to the “IUPAC Commission of Zeolite Nomenclature”.
Also preferred according to the invention are the members of mesoporous zeolite materials of the family which are combined under the name “MCM” in the literature, wherein this name is not a particular structure type (cf. http://www.iza-structure.org/databases). Mesoporous silicates which are called MCM-41 or MCM-48 are particularly preferred according to the invention. MCM-48 has a 3D structure of mesopores, through which the catalytically active metal in the pores is particularly easily accessible. MCM-41 is preferred in particular and has a hexagonal arrangement of mesopores with uniform size. The MCM-41 zeolite material has an SiO 2 /Al 2 O 3 molar ratio of preferably more than 100, more preferably of more than 200 and most preferably of more than 300. Further preferred mesoporous zeolite materials which can be used within the framework of the present invention are those which are called MCM-1, MCM-2, MCM-3, MCM-4, MCM-5, MCM-9, MCM-10, MCM-14, MCM-22, MCM-35, MCM-37, MCM-49, MCM-58, MCM-61, MCM-65 or MCM-68 in the literature.
Which zeolite material is to be used in the method according to the invention primarily depends on the purpose of use of the catalyst to be produced by means of the method according to the invention. A large number of methods are known in the state of the art to tailor the properties of zeolite materials, for example the structure type, the pore diameter, the channel diameter, the chemical composition, the ion exchangeability as well as activation properties, to a corresponding purpose of use.
The zeolite material to be used in the method according to the invention can be for example a silicate, an aluminium silicate, an aluminium phosphate, a silicon aluminium phosphate, a metal aluminium phosphate, a metal aluminium phosphosilicate, a gallium aluminium silicate, a gallium silicate, a boroaluminium silicate, a boron silicate or a titanium silicate, wherein aluminium silicates and titanium silicates are particularly preferred.
By the term “aluminium silicate” is meant according to the definition of the International Mineralogical Association (D. S. Coombs et al., Can. Mineralogist, 35, 1997, 1571) a crystalline substance with spatial network structure of the general formula M n+ [(AlO 2 ) x (SiO 2 ) y ]xH 2 O, which is composed of SiO 4/2 and AlO 4/2 tetrahedra which are linked by common oxygen atoms to form a regular three-dimensional network. The atomic ratio of Si/Al=y/x is always greater than/equal to 1 according to the so-called “Löwenstein's rule” which prohibits two neighbouring negatively charged AlO 4/2 tetrahedra from occurring next to each other. Although more exchange sites are available for metals at a low Si/Al atomic ratio, the zeolite increasingly becomes more thermally unstable.
Within the framework of the present invention, the above-named zeolite materials can be used in the method both in the alkaline form, for example in the Na and/or K form, and in the alkaline earth form, ammonium form or in the H form. In addition, it is also possible to use the zeolite material in a mixed form.
According to a further preferred embodiment of the method according to the invention, it can be provided that a drying step occurs between step a) and step b).
The drying step is carried out between the impregnating and the calcining. The drying temperature is preferably between 25° C. and 250° C., more preferably between 50° C. and 200° C., further preferably between 100° C. and 180° C. and particularly preferably 120° C.
Drying is preferably carried out over a period of more than 1 min, more preferably over a period of more than 1 h, further preferably over a period of more than 5 h and still more preferably over a period of more than 12 h, wherein a drying time of 10 h can be particularly preferred. In this connection, it can moreover be advantageous if the duration of the drying step does not exceed a period of 48 h, preferably does not exceed a period of 24 h.
By the term “calcining” is generally meant heating at high temperatures with the aim of for example materially or structurally altering the treated material or a component thereof. A thermal decomposition, a phase transition or the removal of volatile substances for example can be achieved by a calcining.
Within the framework of the present invention, the calcining is preferably carried out in a temperature range of from 300° C. to 1200° C., more preferably in a temperature range of from 300° C. to 1000° C., further preferably in a temperature range of from 400° C. to 950° C., particularly preferably in a temperature range of from 700 to 900° C. and most preferably in a temperature range of from 730° C. to 900° C.
It is moreover particularly preferred that the calcining is carried out at a temperature of at least 750° C. During a calcining at a temperature of at least 750° C., supported platinum catalysts which, despite high platinum loading of for example 3 wt.-% relative to the weight of the platinum and the open-pored support material, are largely free of sulphur can be obtained by means of the method according to the invention. Thus, by means of the method according to the invention, for example platinum catalysts can be produced which contain 1 to 5 wt.-% platinum, relative to the weight of the platinum and the support material, and have a sulphur content of less than 0.004 wt.-%, relative to the weight of the platinum and the support material. A low sulphur content is particularly advantageous, as sulphur acts as a catalyst poison in particular with regard to noble metals.
The heating rate during the calcining is preferably 0.5° C./min to 5° C./min, more preferably 1° C./min to 4° C./min and particularly preferably 2° C./min.
The duration of the calcining at maximum temperature is preferably in a range of from 1 min to 48 h, more preferably in a range of from 30 min to 12 h and particularly preferably in a range of from 1 h to 7 h, wherein a calcining duration of 5 h or 6 h is particularly preferred.
Within the framework of the present invention, the calcining is carried out under a protective gas. By protective gas are meant gases or gas mixtures which can be used as inert protective atmosphere, for example to prevent unwanted chemical reactions. Within the framework of the present invention, in particular the noble gases helium, neon, argon, krypton or xenon can be used as protective gas, or mixtures of two or more of the above-named, wherein argon is particularly preferred as protective gas. Besides the noble gases or in addition to them, nitrogen for example can also be used as protective gas.
A typical method provided by the present invention comprises the steps of:
a) impregnating an open-pored support material, in particular a zeolite material, in particular a zeolite material of the structure type BEA or a zeolite material from the MCM family, preferably an aluminium silicate or titanium silicate zeolite material, with platinum sulphite acid, in particular with a platinum sulphite acid solution, preferably according to the incipient wetness method; b) calcining, preferably at a temperature above 750° C., the impregnated support material under protective gas, preferably under argon; c) optionally converting the platinum component of the calcined platinum sulphite acid to the oxidation state 0, preferably by reduction by means of hydrogen, preferably at a temperature of at least 100° C.
The present invention furthermore relates to a catalyst precursor or a catalyst that can be obtained according to the method according to the invention. By means of the method according to the invention, supported platinum catalysts can be obtained which are characterized by an increased activity as well as by an increased resistance to thermal ageing compared with the corresponding platinum catalysts known in the state of the art, or catalyst precursors can be obtained which can be converted into platinum catalysts with said advantages.
In particular the present invention relates to a catalyst precursor that can be obtained by a method comprising the steps of:
a) impregnating an open-pored support material, in particular a zeolite material, preferably a zeolite material of the structure type BEA or a zeolite material from the MCM family, with platinum sulphite acid according to the incipient wetness method; b) drying the impregnated support material over a period of 12 h at a temperature of 120° C.; c) calcining the impregnated and dried support material over a period of 5 h at 790° C. under argon.
In particular the present invention relates in addition to a supported Pt catalyst that can be obtained by a method comprising the steps of:
a) impregnating an open-pored support material, in particular a zeolite material, preferably a zeolite material of the structure type BEA or a zeolite material from the MCM family, with platinum sulphite acid according to the incipient wetness method; b) drying the impregnated support material over a period of 12 h at a temperature of 120° C.; c) calcining the impregnated and dried support material over a period of 5 h at 790° C. under argon; d) converting the platinum component of the calcined platinum sulphite acid to the oxidation state 0 by reducing the platinum component by means of a gas consisting of 5 vol.-% hydrogen in nitrogen over a period of 5 h at a temperature of 300° C.
The present invention furthermore relates to a catalyst comprising an open-pored support material, which is preferably a zeolite material, as well as platinum of oxidation state 0, wherein the XRD spectrum of the catalyst is free of signals of elemental platinum. Such catalysts can be produced by means of the method according to the invention. It is presumed that the XRD spectrum of the catalyst is free of Pt signals, as the outer surface of the support material is substantially free or completely free of metal particles of a size to be able to diffract X-radiation according to the diffraction pattern of platinum.
The zeolite material of the catalyst according to the invention can be understood to mean according to a definition of the International Mineralogical Association (D. S. Coombs et al., Can. Mineralogist, 35, 1997, 1571) a crystalline substance with a structure characterized by a framework of tetrahedra linked together. Each tetrahedron consists of four oxygen atoms which surround a central atom, wherein the framework contains open cavities in the form of channels and cages which are normally occupied by water molecules and extra-framework cations which can often be exchanged. The channels of the material are large enough to allow access to guest compounds. In the hydrated materials, the dehydration mostly occurs at temperatures below about 400° C. and is for the most part reversible.
According to a further preferred embodiment of the catalyst according to the invention, it is provided that the zeolite material is a microporous or a mesoporous zeolite material. By the terms “microporous zeolite material” and “mesoporous zeolite material” are to be understood according to the classification of porous solids according to IUPAC (International Union of Pure and Applied Chemistry) zeolite materials the pores of which have a diameter of less than 2 nm and a diameter of from 2 nm to 50 nm respectively.
The zeolite material of the catalyst according to the invention can preferably correspond to one of the following structure types: ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AWO, AWW, BCT, BEA, BEC, BIK, BOG, BPH, BRE, CAN, CAS, CDO, CFI, CGF, CGS, CHA, CHI, CLO, CON, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EMT, EON, EPI, ERI, ESV, ETR, EUO, EZT, FAR, FAU, FER, FRA, GIS, GIU, GME, GON, GOO, HEU, IFR, IHW, ISV, ITE, ITH, ITW, IWR, IWV, IWW, JBW, KFI, LAU, LEV, LIO, LIT, LOS, LOV, LTA, LTL, LTN, MAR, MAZ, MEI, MEL, MEP, MER, MFI, MFS, MON, MOR, MOZ, MSE, MSO, MTF, MTN, MTT, MTW, MWW, NAB, NAT, NES, NON, NPO, NSI, OBW, OFF, OSI, OSO, OWE, PAR, PAU, PHI, PON, RHO, RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAO, SAS, SAT, SAV, SBE, SBS, SBT, SFE, SFF, SFG, SFH, SFN, SFO, SGT, SIV, SOD, SOS, SSY, STF, STI, STT, SZR, TER, THO, TON, TSC, TUN, UEI, UFI, UOZ, USI, UTL, VET, VFI, VNI, VSV, WEI, WEN, YUG and ZON, wherein zeolite materials of the structure type Beta (BEA) are particularly preferred. The above nomenclature of three-letter codes corresponds to the “IUPAC Commission of Zeolite Nomenclature”.
Also preferred according to the invention are the members of mesoporous zeolite materials of the family which are combined under the name “MCM” in the literature, wherein this name is not a particular structure type (cf. http://www.iza-structure.org/databases). Mesoporous silicates which are called MCM-41 or MCM-48 are particularly preferred according to the invention. MCM-48 has a 3D structure of mesopores, through which the catalytically active metal in the pores is particularly easily accessible. MCM-41 is preferred in particular and has a hexagonal arrangement of mesopores with uniform size. The MCM-41 zeolite material has an SiO 2 /Al 2 O 3 molar ratio of preferably more than 100, more preferably of more than 200 and most preferably of more than 300. Further preferred mesoporous zeolite materials which can be used within the framework of the present invention are those which are called MCM-1, MCM-2, MCM-3, MCM-4, MCM-5, MCM-9, MCM-10, MCM-14, MCM-22, MCM-35, MCM-37, MCM-49, MCM-58, MCM-61, MCM-65 or MCM-68 in the literature.
Which zeolite material is contained in the catalyst according to the invention primarily depends on the purpose of use of the catalyst according to the invention. A large number of methods are known in the state of the art to tailor the properties of zeolite materials, for example the structure type, the pore diameter, the channel diameter, the chemical composition, the ion exchangeability as well as activation properties, to a corresponding purpose of use.
The zeolite material of the catalyst according to the invention can be for example a silicate, an aluminium silicate, an aluminium phosphate, a silicon aluminium phosphate, a metal aluminium phosphate, a metal aluminium phosphosilicate, a gallium aluminium silicate, a gallium silicate, a boroaluminium silicate, a boron silicate or a titanium silicate, wherein aluminium silicates and titanium silicates are particularly preferred.
By the term “aluminium silicate” is meant according to the definition of the International Mineralogical Association (D. S. Coombs et al., Can. Mineralogist, 35, 1997, 1571) a crystalline substance with spatial network structure of the general formula M n+ [(AlO 2 ) x (SiO 2 ) y ]xH 2 O, which is composed of SiO 4/2 and AlO 4/2 tetrahedra which are linked by common oxygen atoms to form a regular three-dimensional network. The atomic ratio of Si/Al=y/x is always greater than/equal to 1 according to the so-called “Löwenstein's rule” which prohibits two neighbouring negatively charged AlO 4/2 tetrahedra from occurring next to each other. Although more exchange sites are available for metals at a low Si/Al atomic ratio, the zeolite increasingly becomes more thermally unstable.
In the catalyst according to the invention, the above-named zeolite materials can be present both in the alkaline form, for example in the Na and/or K form, and in the alkaline earth form, ammonium form or in the H form. In addition, it is also possible that the zeolite material is present in a mixed form, for example in an alkaline/alkaline earth mixed form.
According to a further preferred embodiment of the catalyst according to the invention, it is provided that the catalyst comprises 1 to 10 wt.-% platinum, relative to the weight of the platinum and the support material. It was found that, by means of the method according to the invention, supported platinum catalysts can be obtained the XRD spectra of which are free of platinum signals despite relatively high platinum loading and which have a high resistance to thermal ageing despite relatively high platinum loading. Moreover, it can be provided in this connection according to a further preferred embodiment of the catalyst according to the invention that the catalyst comprises 1 to 10 wt.-% platinum, relative to the weight of the platinum and the support material, more preferably 2 to 5 wt.-%, further preferably 2.2 to 4.5 wt.-%, particularly preferably 2.5 to 3.5 wt.-% and most preferably 3 wt.-%.
According to a further preferred embodiment of the catalyst according to the invention, it is provided that the catalyst is free of further metals of oxidation state 0.
As already stated above, according to a preferred embodiment of the catalyst according to the invention, the support material is a zeolite material of the structure type Beta or a zeolite material from the MCM family.
Furthermore, it can be provided according to a further preferred embodiment of the catalyst according to the invention that the BET surface area of the zeolite material is 100 to 1500 m 2 /g, preferably 150 to 1000 m 2 /g and more preferably 200 to 600 m 2 /g. The BET surface area is to be determined according to the single-point method by adsorption of nitrogen according to DIN 66132.
According to a further preferred embodiment of the catalyst according to the invention, it can be provided that the catalyst is formed as powder, as shaped body or as monolith. Preferred shaped bodies are for example spheres, rings, cylinders, perforated cylinders, trilobes or cones and a preferred monolith is for example a honeycomb body.
By the dispersion of a supported metal catalyst is meant the ratio of the number of all surface metal atoms of all metal particles of a support to the total number of all metal atoms of the metal particles. In general it is preferred if the dispersion value is relatively high, as in this case as many metal atoms as possible are freely accessible for a catalytic reaction. This means that, given a relatively high dispersion value of a supported metal catalyst, a specific catalytic activity of same can be achieved with a relatively small quantity of metal used. According to a further preferred embodiment of the catalyst according to the invention, the dispersion of the platinum particles is 50 to 100%, preferably 55 to 90%, further preferably 60 to 90%, particularly preferably 75 to 85%. The values of the dispersion are to be determined by means of hydrogen according to DIN 66136-2.
In principle, it is advantageous if the platinum is present in the catalyst according to the invention in particles as small as possible, as the platinum particles then have a very high degree of dispersion. However, a favourable average particle diameter also depends on the application in which the catalyst is to be used, as well as on the pore distribution and in particular the pore radii and channel radii of the support material. According to a preferred embodiment of the catalyst according to the invention, the metal particles have an average diameter which is smaller than the pore diameter and is larger than the channel diameter of the support material. The metal particles are thereby mechanically caught in the support material, which leads to a high resistance to thermal ageing of the catalyst according to the invention. For example, the metal particles have an average diameter of from 0.5 to 5 nm, preferably an average diameter of from 0.5 to 4 nm, more preferably an average diameter of from 0.5 to 3 nm and particularly preferably an average diameter of from 0.5 to 2 nm. The average particle diameter is preferably to be determined by decomposition of the support material and measuring the remaining Pt particles by means of transmission electron microscopy (TEM).
The present invention furthermore relates to the use of a catalyst according to the invention in a catalysis process which is carried out above a temperature of 700° C.
According to a preferred embodiment of the use according to the invention, the catalysis process is a purification of industrial or automotive exhaust gases, such as preferably car, ship, train exhaust gases, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
The following examples serve in connection with the drawings to illustrate the invention. There are shown in:
FIG. 1 : XRD spectrum of a first catalyst ( 1 ) according to the invention produced according to the method according to the invention as well as of a first comparison catalyst ( 2 );
FIG. 2 : Propane conversion of the first catalyst (squares), of the first catalyst after ageing (circles) and of the first comparison catalyst (triangles) in the heating phase against the temperature;
FIG. 3 : Propane conversion of the first catalyst (squares) and of the first comparison catalyst (triangles) in the constant temperature phase (550° C.) against time;
FIG. 4 : Propane conversion of the first catalyst (squares) and of the first comparison catalyst (triangles) in the cooling phase against the temperature;
FIG. 5 : XRD spectra (in sections) of a second catalyst ( 11 ) according to the invention produced according to the method according to the invention as well as a second ( 13 ) and a third ( 12 ) comparison catalyst;
FIG. 6 : Propane conversion of the second catalyst ( 11 ) according to the invention, of the second comparison catalyst ( 13 ) and of the third comparison catalyst ( 12 ) in the heating phase against the temperature.
DETAILED DESCRIPTION OF THE INVENTION
Example 1
A powdery aluminium silicate zeolite material (20 g) of the structure type Beta (BEA) in the H form with an Si/Al2 atomic ratio of 35 was impregnated with 21.9 ml of an aqueous platinum sulphite acid solution containing 3.2 wt.-% Pt (calculated as metal) by means of the incipient wetness method. The absorption of water of dried BEA is (over night at 120° C.) 9.2 g H 2 O/10 g BEA. 12.96 g H 2 O was added to the PSA solution. The solution had a Pt concentration of 3.2 wt.-% (the impregnation was carried out with this solution).
After the impregnation, the zeolite material was dried over night at a temperature of 120° C.
After the drying, the impregnated zeolite material was calcined in an argon atmosphere over a period of 5 h at a temperature of 770° C. The heating rate was 2° C./min and the argon volumetric flow rate during the heating and calcining phase was 2 l/min.
After the calcining, the zeolite material loaded with platinum was reduced at a temperature of 300° C. by means of a gas containing 5 vol.-% hydrogen in nitrogen (2 l/min) over a period of 5 h. The heating rate was 2° C./min.
Example 2
The catalyst obtained according to Example 1 was calcined in order to age it for a period of 10 h at a temperature of 650° C. in air (heating rate: 10° C./min).
Comparison Example 1
A catalyst was produced analogously to Example 1, with the only difference that the calcining took place in air.
XRD Measurement 1:
The catalyst produced according to Example 1 and Comparison Example 1 was measured by X-ray diffractometry. The measured XRD spectra are represented in FIG. 1 , wherein the spectrum of Example 1 and of Comparison Example 1 are given the reference numbers 1 and 2 respectively.
The XRD spectrum of the catalyst produced according to Example 1 (calcining under argon) displays no Pt signals, whereas the XRD spectrum of the catalyst produced according to Comparison Example 1 (calcining in air) displays clear Pt signals. In fact the signal at a 2-theta value of about 40° is the Pt(110) reflection (110 are the Miller indices), the signal at a 2-theta value of about 46.5° is the Pt(200) reflection.
The absence of Pt reflections in the catalyst according to Example 1 is an indication that, despite the relatively high calcining temperature, no larger platinum clusters have formed on the outer surface of the zeolite material and the platinum is present in the zeolite material predominantly in highly dispersed form.
Elemental Analysis:
Within the framework of a completed elemental analysis, it was established that the catalyst according to Example 1 has a sulphur content of less than 0.004 wt.-%, while the catalyst produced according to Comparison Example 1 has a sulphur content of 0.155 wt.-%.
Activity Test 1:
The catalyst produced according to Examples 1 and 2 as well as according to Comparison Example 1 was subjected to a conversion of propane as activity test under the test conditions below.
Test Conditions:
Particle size:
0.5-1.25 mm
Temperature profile:
room temperature (RT) →
550° C. (5 h) → RT
Heating rate:
10° C./min
Cooling rate:
20° C./min
CO concentration:
800 ppm
Propane concentration:
200 ppm
Gas hourly space velocity (GHSV):
100 000 h −1
Initial weight:
7 g
Catalyst volume:
14 ml
FIG. 2 shows the curve shapes of the measured propane conversions in the heating phase against the temperature, FIG. 3 the curve shapes of the propane conversions during the constant temperature phase against time and FIG. 4 shows the curve shapes of the propane conversions in the cooling phase against the temperature, wherein the curve shapes of the catalysts of Examples 1 and 2 and Comparison Example 1 are denoted by squares, circles and triangles respectively.
In the heating phase, the two catalysts according to Example 1 and Comparison Example 1 display the same activity and achieve a conversion of approximately 95% ( FIG. 2 ). During the constant temperature phase, the activity of the catalyst calcined in air according to Comparison Example 1 clearly reduces, whereas the catalyst calcined under argon according to Example 1 displays almost the same activity over the whole constant temperature phase ( FIG. 3 ). In the cooling phase, the catalyst according to Example 1 also displays an increased activity compared with that of Comparison Example 1 ( FIG. 4 ). The curve shapes for the catalyst according to Example 1 are almost identical in the heating and cooling phases ( FIGS. 2 and 4 ).
The thermally aged catalyst according to Example 2 displays a clearly reduced activity in the range of lower temperatures, but achieves the conversion of the unaged catalyst according to Example 1 at a temperature of 550° C. ( FIG. 2 ).
Comparison Example 2
20 g of powdery aluminium silicate zeolite material of the structure type MFI (ZSM-5) in the ammonium form with an Si/Al atomic ratio of 27 was impregnated with 3 wt.-% platinum (calculated as metal and relative to the weight of the zeolite material and the platinum) in the form of (NH 3 ) 4 Pt(NO 3 ) 2 by means of the incipient wetness method.
After the impregnation, the zeolite material was dried over night at a temperature of 120° C.
After the drying, the impregnated zeolite material was calcined in an argon atmosphere over a period of 5 h at a temperature of 790° C. The heating rate from room temperature to 300° C. was 0.3° C./min, the heating rate from 300° C. to 790° C. was 4° C./min and the argon volumetric flow rate during the heating and calcining phase was 2 l/min. The decomposition of the (NH 3 ) 4 Pt(NO 3 ) 2 proceeds in a reductive manner, with the result that Pt of oxidation state 0 forms during the calcining.
Comparison Example 3
A catalyst was produced analogously to Comparison Example 2, with the only difference that a powdery aluminium silicate zeolite material of the structure type Beta (BEA) in the H form with a Si/Al2 atomic ratio of 35 was used as zeolite material.
Example 3
A catalyst was produced analogously to Comparison Example 2, with the differences that a powdery aluminium silicate zeolite material of the structure type Beta (BEA) in the H form with an Si/Al2 atomic ratio of 35 was used as zeolite material, that the heating rate from room temperature to 790° C. was 2° C./min and that after the calcining the zeolite material loaded with platinum was reduced at a temperature of 300° C. by means of a gas containing 5 vol.-% hydrogen in nitrogen (2 l/min) over a period of 5 h. The heating rate was 2° C./min.
XRD Measurement 2:
The catalysts produced according to Example 3 and according to Comparison Examples 2 and 3 were measured by X-ray diffractometry. The measured XRD spectra are represented in FIG. 5 in sections, wherein the spectrum of Example 3 and of Comparison Examples 2 and 3 are given the reference numbers 11 , 13 and 12 respectively.
The XRD spectrum of the catalyst produced according to Example 3 displays no Pt reflections at a 2-theta value of about 40°, whereas the XRD spectra of the catalysts produced according to Comparison Examples 2 and 3 display clear Pt reflections. In fact, the signal at a 2-theta value of about 40° is the Pt(110) reflection.
The absence of Pt reflections in the catalyst according to Example 3 is an indication that no larger platinum particles have formed on the outer surface of the zeolite material and the platinum is present in the zeolite material predominantly in highly dispersed form.
Activity Test 2:
The catalysts produced according to Example 3 as well as according to Comparison Examples 2 and 3 were subjected to a conversion of propane as activity test under the test conditions below.
Test Conditions:
Particle size:
0.5-1.25 mm
Temperature profile:
room temperature (RT) →
550° C.
Heating rate:
10° C./min
CO concentration:
800 ppm
Propane concentration:
200 ppm
Gas hourly space velocity (GHSV):
100 000 h −1
Initial weight:
7 g
Catalyst volume:
14 ml
FIG. 6 shows the curve shapes of the measured propane conversions in the heating phase against the temperature, wherein the curve shape of the catalyst according to Example 3 as well as those according to Comparison Examples 2 and 3 are given the reference numbers 11 , 13 and 12 respectively. The activity test clearly shows the increased activity of the catalyst according to the invention produced by means of the method according to the invention.
The light-off temperatures at which 50% of the propane used is converted are 243° C. for the catalyst produced according to Example 3 and 498° C. and 356° C. for the catalysts produced according to Comparison Examples 2 and 3 respectively. | A supported platinum catalyst comprising an open-pored support material and platinum of oxidation state 0, wherein an XRD spectrum of the catalyst is free of signals of elemental platinum. | 1 |
BACKGROUND
[0001] 1. Field of the Invention
[0002] The present invention generally relates drilling and, in particular, to activation of downhole safety devices.
[0003] 2. Description of the Related Art
[0004] Boreholes are drilled deep into the earth for many applications such as carbon sequestration, geothermal production, and hydrocarbon exploration and production. In all of the applications, the boreholes are drilled such that pass through or can allow for access to a material (e.g., a gas or fluid) contained in a formation located below the earth's surface. Many different types of tools and instruments may be disposed in the boreholes to perform various tasks and some of these can be utilized to take measurements of various values while the borehole is being drilled.
[0005] One disadvantageous phenomenon that can arise while drilling is referred to as “drilling kick” or simply “kick.” Kick generally refers to the condition where a formation fluid or formation gas flows from the formation into the borehole while drilling. Kick can occur when formation pressure exceeds the hydrostatic pressure exerted on the formation by drilling mud utilized in drilling the borehole. This type of kick is generally referred to as “underbalanced kick.” Another type of kick referred to as “induced kick” can occur when movement of the drill sting or casing causes the pressure in the borehole to fluctuate.
[0006] Regardless of the cause, the kick can, in extreme cases, result in an uncontrolled flow of formation fluid or gases into the atmosphere at the surface in a phenomenon referred to as “blowout.” To prevent blowout, a blowout preventer is typically installed in the space between the drill pipe and the casing at the surface. The blowout preventer is activated when a kick is detected and seals off the annulus between the drill pipe and the casing to prevent the fluid or gasses from escaping. Early detection of a kick is required to effectively operate the blowout preventer and typically includes visual observation of bubbles in the drilling mud at the surface.
BRIEF SUMMARY
[0007] Disclosed is a drilling system for drilling a borehole that includes a drill string including a bottom hole assembly and a telemetry system coupled together. The system also includes a communication device coupled to the drillstring configured to transmit sensor data to and receive control data from a control unit located at a surface location through the telemetry system and a sensor coupled to the drillstring, the sensor providing the sensor data to the communication device. The system also includes a downhole safety device coupled to the drill string and in operable communication with the communication device, the downhole safety device configured to actuate after receiving an activation signal initiated by the control unit.
[0008] Also disclosed is a method of actuating a downhole safety device in a drilling system that includes collecting information indicative of borehole conditions at a downhole location; transmitting the information to a surface control unit; determining that the downhole safety device should be actuated; sending an actuation signal through a telemetry system to the downhole safety device; actuating the downhole safety device using the actuation signal.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
[0010] FIG. 1 illustrates a drilling system in which embodiments of the present invention may be implemented; and
[0011] FIG. 2 is flow chart illustrating a method according to one embodiment of the present invention.
DETAILED DESCRIPTION
[0012] A detailed description of one or more embodiments of the disclosed apparatus and method presented herein is by way of exemplification and not limitation with reference to the Figures.
[0013] FIG. 1 illustrates FIG. 1 is a schematic diagram of an exemplary drilling system 100 that includes a drill string having a drilling assembly attached to its bottom end that can be operated according to the exemplary methods apparatus disclosed herein. FIG. 1 shows a drill string 120 that includes a drilling assembly or bottomhole assembly (“BHA”) 190 conveyed in a borehole 126 . The drilling system 100 includes a conventional derrick 111 erected on a platform or floor 112 which supports a rotary table 114 that is rotated by a prime mover, such as an electric motor (not shown), at a desired rotational speed. A tubing (such as drill pipe) 122 having the drilling assembly 190 attached at its bottom end extends from the surface to the bottom 151 of the wellbore 126 . The tubing 122 is so-called wired pipe in one embodiment and allows for high-speed bi-directional communication through it.
[0014] A drill bit 150 , attached to drilling assembly 190 , disintegrates the geological formations when it is rotated to drill the borehole 126 . The drill string 120 is coupled to a drawworks 130 via a Kelly joint 121 , swivel 128 and line 129 through a pulley. Drawworks 130 is operated to control the weight on bit (“WOB”). The drill string 120 can be rotated by a top drive (not shown) instead of by the prime mover and the rotary table 114 . The prime mover/rotary table 114 combination or a top drive or any other means of turning drill string 120 shall be referred to as drill string actuator herein. The operation of the drawworks 130 is known in the art and is thus not described in detail herein.
[0015] A suitable drilling fluid 131 (also referred to as “mud”) from a source 132 thereof, such as a mud pit, is circulated under pressure through the drill string 120 by a mud pump 134 . The drilling fluid 131 passes from the mud pump 134 into the drill string 120 via a de-surger 136 and the fluid line 138 . The drilling fluid 131 discharges at the borehole bottom 151 through openings in the drill bit 150 . The returning drilling fluid 131 b circulates uphole through the annular space 127 between the drill string 120 and the borehole 126 and returns to the mud pit 132 via a return line 35 and drill cutting screen 185 that removes the drill cuttings 186 from the returning drilling fluid 131 b.
[0016] In some applications, the drill bit 150 is rotated by rotating the drill pipe 122 . However, in other applications, a downhole motor 155 (mud motor) disposed in the drilling assembly 190 also rotates the drill bit 150 . The rate of penetration (“ROP”) for a given drill bit and BHA largely depends on the WOB or the thrust force on the drill bit 150 and its rotational speed.
[0017] A surface control unit or controller 140 receives signals from downhole sensors and devices and processes such signals according to programmed instructions provided from a program to the surface control unit 140 . The surface control unit 140 displays desired drilling parameters and other information on a display/monitor 141 that is utilized by a human operator to control the drilling operations. The surface control unit 140 can be a computer-based unit that can include a processor 142 (such as a microprocessor), a storage device 144 , such as a solid-state memory, tape or hard disc, and one or more computer programs 146 in the storage device 144 that are accessible to the processor 142 for executing instructions contained in such programs to perform the methods disclosed herein. The surface control unit 140 can process data relating to the drilling operations, data from the sensors and devices on the surface, and data received from downhole and can control one or more operations of the downhole and surface devices.
[0018] The drilling assembly 190 also contains formation evaluation sensors or devices (also referred to as measurement-while-drilling, “MWD,” or logging-while-drilling, “LWD,” sensors) determining borehole pressure, formation pressure, resistivity, density, porosity, permeability, acoustic properties, nuclear-magnetic resonance properties, corrosive properties of the fluids or formation downhole, salt or saline content, and other selected properties of the formation 195 surrounding the drilling assembly 190 . Such sensors are generally known in the art and for convenience are generally denoted herein by numeral 165 and can include, for example, resistivity sensors, density sensors, porosity sensors, permeability sensors, temperature sensors, pressure sensors, vibration sensors, bending moment sensors, rotation sensors, orientation sensors and shear sensors. The drilling assembly 190 can further include a variety of other sensors and communication devices 159 for controlling and/or determining one or more functions and properties of the drilling assembly (such as velocity, vibration, bending moment, acceleration, oscillations, whirl, stick-slip, etc.) and drilling operating parameters, such as weight-on-bit, fluid flow rate, pressure, temperature, rate of penetration, azimuth, tool face, drill bit rotation, etc.
[0019] A suitable telemetry sub (communication device) 180 using, for example, two-way telemetry, is also provided as illustrated in the drilling assembly 190 and provides information from the various sensors to the surface control unit 140 through the wired pipe 122 . The telemetry sub 180 can also provide control or activation data received from the control unit 140 to the sensors or other devices located at or near the BHA 190 . In one embodiment, the telemetry sub 180 provides activation signals to downhole safety devices 167 .
[0020] Still referring to FIG. 1 , the drill string 120 further includes an energy conversion device 160 . In an aspect, the energy conversion device 160 is located in the BHA 190 to provide an electrical power or energy, such as current, to sensors 165 and/or communication devices 159 . Energy conversion device 160 can include a battery or an energy conversion device that can for example convert or harvest energy from pressure waves of drilling mud which are received by and flow through the drill string 120 and BHA 190 . Alternately, a power source at the surface can be used to power the various equipment downhole.
[0021] The drill string 120 further includes one or more downhole safety devices 167 . These safety devices 167 can include, for example, blowout preventers (BOPs). The BOPs, as is known in the art, are operated to seal incoming fluid from the formation 169 from traversing up the annulus between the drill pipe 122 and the borehole 126 . It shall be understood that the safety devices 167 can receive an activation signal from the control unit 140 through the telemetery sub 180 . In some cases, a surface BOP can also be provided that seals fluid from escaping into the atmosphere.
[0022] According to one embodiment of the present invention, the sensors 165 can sense one or more of formation pressure, flow rate of the drilling mud and composition of the drilling mud. Information collected by the sensors 165 is provided to the controller 140 through wired pipe 122 . At the controller 140 it is determined if a kick is about to or has occurred. The determination can be automatic or based on analysis of the data by an operator. If kick has or is about to occur, the controller 140 can transmit a signal through the wired pipe 122 to safety devices 167 that cause them to activate.
[0023] In prior art applications, after detection of a kick at the surface, an activation of the safety devices 167 has heretofore been initiated manually with significant time delay from surface by dropping a ball or the like or sending a downlink. In either case, the safety devices 167 are actuated independent of the other portions of the drilling system 100 . Such activation, while suitable for reducing or eliminating the effects of kick, is not very effective due to the time delay and can create additional problems. For instance, if the safety device 167 is activated before the rotary table 114 is stopped, the drill string 120 could be damaged. In some cases a blow-out will not be even recognized (underground blow-out) at surface.
[0024] By making the determination of a kick condition based on downhole information at the surface, other related systems can be stopped or altered in the correct order. For instances, if the sensors detect conditions indicative of kick, the rotary table 114 could be stopped, a surface BOP (not shown) activated, and then the controller 140 could then transmit the signal to cause the safety devices 167 to actuate. In short, due to the high speed communication capabilities of e.g. wired pipe, the correct sequencing of a kick related shut-down can be controlled from the surface in real-time.
[0025] Such safety device can also be used in case of mud losses to shut-in the annulus and prevent an underbalanced condition causing borehole instability or a kick initiation.
[0026] FIG. 2 is a flow chart showing a method according to one embodiment. At process 200 current drilling conditions are monitored by sensors located on or near the BHA of a drill string. The conditions can include, for example, the flow rate or composition of the drilling mud and hydrostatic pressure of the formation to name but a few. At process 202 the drilling conditions are transmitted to the surface. At the surface, the drilling conditions are provided to a control unit as indicated at process 204 . It shall be understood that the control unit can be located at the same location as or remote from the location where the drilling is being conducted. That is, the control unit could be remote from the drilling rig in one embodiment.
[0027] Regardless of where the control unit is located, at block 206 a determination is made that a downhole safety device located along the drill string needs to be actuated. This determination can be made either by an operator, fully automatically by the control unit using an expert system approach, or combinations of operator determined and automatic control. At process 208 at least one other portion of the drilling system (e.g., the rotary table) is provided a command to cause it vary its operation (e.g., stop). After process 208 is completed, at process 210 , an activation command is sent to from the control unit to the downhole safety device. In some instances, downhole conditions are further monitored to determine is the activation command achieved the desired result or if further safety devices need to be actuated or other actions taken.
[0028] Elements of the embodiments have been introduced with either the articles “a” or “an.” The articles are intended to mean that there are one or more of the elements. The terms “including” and “having” are intended to be inclusive such that there may be additional elements other than the elements listed. The conjunction “or” when used with a list of at least two terms is intended to mean any term or combination of terms. The terms “first,” “second,” and “third” are used to distinguish elements and are not used to denote a particular order.
[0029] It will be recognized that the various components or technologies may provide certain necessary or beneficial functionality or features. Accordingly, these functions and features as may be needed in support of the appended claims and variations thereof, are recognized as being inherently included as a part of the teachings herein and a part of the invention disclosed.
[0030] While the invention has been described with reference to exemplary embodiments, it will be understood that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications will be appreciated to adapt a particular instrument, situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. | A drilling system for drilling a borehole includes a drill string including a bottom hole assembly and a telemetry system coupled together and a communication device coupled to the drillstring configured to transmit sensor data to and receive control data from a control unit located at a surface location through the telemetry system. The system also includes a sensor coupled to the drillstring, the sensor providing the sensor data to the communication device and a downhole safety device coupled to the drill string and in operable communication with the communication device, the downhole safety device configured to actuate after receiving an activation signal initiated by the control unit. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the invention relate to the field of semiconductor device fabrication. More particularly, the present invention relates to an apparatus and method for measuring the incidence angle for an ion beam in an ion implanter.
2. Discussion of Related Art
Ion implantation is a process used to dope impurity ions into a semiconductor substrate to obtain desired device characteristics. A precise doping profile in a semiconductor substrate and associated thin film structure is critical for proper device performance. An ion beam is directed from an ion source chamber toward a substrate. The depth of implantation into the substrate is based on the ion implant energy and the mass of the ions generated in the source chamber. In addition, the beam dose (the amount of ions implanted in the substrate) and the beam current (the uniformity of the ion beam) can be manipulated through the use of a mass analyzing magnet, a corrector magnet and one or more acceleration and deceleration stages along the ion beam path to provide a desired doping profile in the substrate. However, throughput or manufacturing of semiconductor devices is highly dependent on the uniformity of the ion beam on the target substrate to produce the desired device characteristics.
Generally, beam current, energy contamination and uniformity both of ion beam current density and angle of implantation are the parameters that jeopardize device throughput during semiconductor manufacturing processes. For example, if the beam current is too low, this will reduce the throughput of the implanter for a given total ion dose. Energy contamination occurs when there is a small fraction of the ion beam that is at a higher energy than desired. This small fraction of the ion beam at a higher energy level will rapidly increase the depth of the desired junction that is formed in the substrate when creating an integrated circuit and lead to degraded performance of the desired circuit profile. If the ion beam current density and angle of implantation are not uniform, there will be variations in the device properties formed across the semiconductor substrate. These variations in beam current and angle of implantation can compromise the desired device characteristics which could produce lower manufacturing yields and lead to higher processing costs. Thus, there is a need to control at least one or more of these parameters to provide current uniformity for ion implantation systems when manufacturing semiconductor devices.
SUMMARY OF THE INVENTION
Exemplary embodiments of the present invention are directed to an apparatus for measuring the incidence angles of an ion beam in an ion implanter. In an exemplary embodiment, an ion beam detector assembly includes a plurality of pairs of ion current sensors disposed along a path of an ion beam in an ion implanter. Each of the pairs of ion current sensors is disposed on a detector array along a perpendicular axis with respect to the ion beam. The detector assembly starts from a position outside of the ion beam path and moves across the beam and terminates outside the beam path on the opposite side. As the detector assembly moves across the beam a first of the current sensors detects a first beam current, and a second of the current sensors detects a second beam current where each of the first and second detected beam currents are used to determine an angle of incidence of the ion beam. A blocker panel is disposed a distance ‘d’ upstream from the plurality of pairs of ion current sensors. The blocker panel is configured to block portions of the ion beam having a first group of angles of incidence from reaching a first section of each of the ion current sensors and allowing portions of the ion beam having a second group of angles of incidence to reach a second section of each of the ion current sensors.
In an exemplary method of measuring angles of incidence of an ion beam includes replacing a target wafer with an ion beam detector assembly having a plurality of current sensors. An ion beam is provided which is incident on the detector assembly. The beam current associated with the ion beam is detected by the plurality of current sensors. The detector assembly moves across the ion beam measuring beam currents. The angle of incidence of the ion beam is calculated using the detected beam currents from the plurality of current sensors. The angles of incidence are analyzed to determine the uniformity of the ion beam. The beam current is adjusted based on the calculated incidence angles.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a block diagram of a representative ion implanter including an incident angle detector assembly in accordance with an embodiment of the present invention.
FIG. 1A is a schematic view of the movement of the detector assembly with respect to the ion beam path in accordance with an embodiment of the present invention.
FIG. 2 is a perspective view of an exemplary detector assembly in accordance with an embodiment of the present invention.
FIG. 3A is a front view of the detector assembly of FIG. 2 in accordance with an embodiment of the present invention.
FIG. 3B is an end view of the detector assembly of FIG. 2 in accordance with an embodiment of the present invention.
FIG. 3C is a side view of the detector assembly of FIG. 2 in accordance with an embodiment of the present invention.
FIG. 4 is a flow diagram illustrating an exemplary method of monitoring uniformity of ion implantation in accordance with an embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention, however, may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, like numbers refer to like elements throughout.
FIG. 1 is a block diagram of an exemplary ion implanter 100 including an ion source chamber 102 . A power supply 101 supplies the required energy to source 102 which is configured to generate ions of a particular species. The ion source chamber 102 typically includes a heated filament which ionizes a feed gas introduced into the chamber to form charged ions and electrons (plasma). The heating element may be, for example, a Bernas source filament, an indirectly heated cathode (IHC) assembly or other thermal electron source. Different feed gases are supplied to the ion source chamber to obtain ion beams having particular dopant characteristics. For example, the introduction of H 2 , BF 3 and AsH 3 at relatively high chamber temperatures are broken down into mono-atoms having high implant energies. High implant energies are usually associated with values greater than 20 keV. For low-energy ion implantation, heavier charged molecules such as decaborane, carborane, etc., are introduced into the source chamber at a lower chamber temperature which preserves the molecular structure of the ionized molecules having lower implant energies. Low implant energies typically have values below 20 keV.
The generated ions are extracted from the source through a series of electrodes 104 and formed into a beam 105 which passes through a mass analyzer magnet 106 . The mass analyzer is configured with a particular magnetic field such that only the ions with a desired mass-to-charge ratio are able to travel through the analyzer for maximum transmission through a mass resolving slit and onto deceleration stage 108 . The deceleration stage comprising multiple electrodes with defined apertures that allow the ion beam to pass. By applying different combinations of voltage potentials to these electrodes, the deceleration stage manipulates the ion energies in the beam.
Corrector magnet 110 is disposed downstream of the deceleration state and is energized to deflect ion beamlets in accordance with the strength and direction of the applied magnetic field to provide a ribbon beam targeted toward a work piece or substrate 114 positioned on a support or platen. In other words, the corrector magnet shapes the ion beam generated from the deceleration stage into the correct form for deposition onto the workpiece. In addition, the corrector magnet filters out any ions from the beam that may have been neutralized while traveling through the beam line. In some embodiments, a second deceleration stage 112 may be disposed between corrector magnet 110 and target work piece 114 . This second deceleration stage comprising a deceleration lens receives the ion beam from the corrector magnet and further manipulates the energy of the ion beam before it hits the workpiece 114 .
As the beam hits the work piece 114 , the ions in the beam penetrates the work piece coming to rest beneath the surface to form a region of desired conductivity, whose depth is determined by the energy of the ions. In order to ensure that the ions penetrate the work piece at a desired incident angle and beam current, system 100 includes detector assembly 116 having a plurality of sensors such as, for example Faraday cups, configured to detect the beam current measured at various points along the path through the ion beam 105 . The changes in beam current relative to the various measured points using the detector assembly 116 yields a measurement of the ion beam incident angle as described with respect to the process outlined below. The detector assembly 116 replaces work piece 114 and the profile measured at each of these sensors is used to determine the angle of incidence of the beam 105 . Based on these measurements, the profile may be modified to improve implant uniformity. Once the desired beam current and incident angle is obtained, the detector assembly 116 is replaced with work piece 114 and the detector assembly is removed from the beam line. In this manner, feedback from the detector assembly may be used to manipulate electromagnets along the beam line to provide a desired beam profile.
FIG. 1A is a schematic drawing illustrating the movement of detector assembly 116 from a starting position A to an end position B. Detector assembly 116 starts from a position A outside of the ion beam path, moves horizontally across the beam 105 and terminates at a position B outside the beam path on the opposite side thereof. As the assembly moves across the beam 105 and the current values detected by each of the detector elements is recorded. The position of the detector assembly 116 as it moves across the beam is also recorded and associated with the corresponding current value detected by the respective detector element.
FIG. 2 is a perspective view of detector assembly 116 including a blocker panel 210 and a graphite array 220 having Faradays defined by Faraday pixels 220 1 . . . 220 N and Faraday bodies 221 1 . . . 221 N disposed therein. The blocker panel 210 is disposed a given distance “d” away from the array 220 . The Faradays are arranged in pairs along the X axis and are configured to receive a portion of the ion beam not blocked by panel 210 . Each Faraday measures the beam current as the assembly 200 is moved in direction X. In particular, each Faraday receives a portion of the analyzed beam 105 and produces an electrical current based on the representative current thereof. Each Faraday is connected to a current meter to detect the amperage (e.g. mA) and based on the area of the respective Faraday pixel 220 1 . . . 220 N , determines the current (e.g. mA/cm2) of the ion beam received by the Faraday. For explanation purposes, the beam 105 shown in FIG. 2 is a portion of the beam typically incident on a work piece. The body portions 221 1 . . . 221 N of the Faradays extend a distance in direction Z in order to prevent the beamlets of beam 105 which enter pixels 220 1 . . . 220 N froth escaping. As beam 105 is incident on Faraday pixels 220 1 and 220 2 , the beam current is measured by the respective Faradays and the incident angle A of the beam 105 on the particular pixels is calculated by using the following equation:
A =ArcTan((( Ia−Ib )* w )/(( Ia+Ib )*2 d )) (Equation 1)
where Ia and Ib are the beam currents measured at a first and second of a pair of Faraday pixels (e.g. Faraday pixels 220 1 and 220 2 ), ‘w’ is the width of a particular one of the array of Faraday pixels 220 1 . . . 220 N and d is the distance from blocker panel 210 to array 220 (as illustrated in FIGS. 3A-3C ). Because of the different positions of each of the pixels 220 1 . . . 220 N along the array 220 , each measures different amounts of the beam current depending on the angle of incidence for the particular Faraday. In this manner, N/2 pairs of Faradays are used to provide a two-dimensional array of incident angles of beam 105 in direction Y based on the number of detectors in direction X. The two dimensional array of angles is used to adjust the lenses and magnets in the ion implanter to obtain the desired beam angles incident on a work piece. In addition, the larger the distance d, the greater the resolution of the incident angles. However, a process trade off exists between greater angle resolution versus detection of smaller incident angles. The calculation of incidence angles can be repeated and the until the array of incidence angles is acceptable for a particular implantation profile.
FIG. 3B is a front view of the detector assembly 116 shown in FIG. 2 including a blocker panel 210 and graphite array 220 housing pairs of Faraday pixels 220 1 . . . 220 N . Each of the pixels 220 1 . . . 220 N has a width “w”, a first portion of which is disposed behind blocker panel 210 and a second portion of which is not disposed behind blocker panel 210 . Although part of a pixel is behind blocker panel 210 , each pixel is configured to detect a portion of ion beam 105 incident thereon. The pixels 220 1 . . . 220 N are shown in pair-wise linear columns where the current detected by each pixel pair used to determine the incident angle in accordance with Equation 1 above. A first blocker support post 240 1 is connected to graphite array 220 and blocker panel 210 at a first end of detector assembly 116 . A second blocker support post 240 2 is connected to graphite array 220 and blocker panel 210 at a second end of detector assembly 116 . Blocker panel 210 is a substantially rectangular piece of graphite, however alternative conductive materials and shapes may be employed. In addition, blocker panel 210 may also be capable of rotation away from array 220 about one of the support posts 240 . This may be done to allow calibration of the detectors in the array.
Blocker panel 210 is configured to block beamlets of the incident ion beam 105 from reaching the first portion of each Faraday pixel 220 1 . . . 220 N . For example, a first portion 220 a of pixel 220 2 which has a width approximately w/2 is disposed behind blocker panel 210 and can only receive beamlets of ion beam 105 which are incident thereon at an angle with respect to the planar surface of the array 220 . In other words, beamlets of the ion beam 105 which are perpendicular to first portion 220 a of pixel 220 2 will be blocked by blocker panel 210 . Similarly, beamlets of the ion beam 105 which are less than orthogonal on pixel portion 220 a (i.e. toward pixel 220 1 ) will likewise be blocked from reaching pixel portion 220 a by blocker panel 210 . However, second pixel portion 220 b of pixel 220 2 which is also has a width of approximately w/2 is not disposed behind blocker panel 210 and therefore is configured to receive beamlets of the ion beam 105 which are substantially orthogonal to pixel portion 220 b and beamlets of the ion beam 105 which are less than orthogonal to pixel portion 220 b . The width of each of the pixel portions 220 a and 220 b may have alternative dimensions depending on the range of incident angles being detected.
The relationship of the Faraday pixels and the ion beam 105 is illustrated more clearly in FIG. 3B which is an end view of detector assembly 116 taken in direction A. FIG. 3B illustrates blocker panel 210 , blocker support post 240 2 array 220 , pixel pair 220 1 and 220 2 and pixel bodies 221 1 and 221 2 , respectively. By way of example, beamlets 105 1 . . . 105 4 are incident on Faraday pixels 220 1 and 220 2 of detector assembly 116 . Beamlet portion 105 1 of ion beam 105 is incident on and received by pixel 220 2 at an incident angle. Beamlet portion 105 2 is orthogonal to pixel 220 2 and is blocked by blocker panel 210 . Beamlet portion 105 3 of ion beam 105 is orthogonal to pixel 220 1 and is blocked by blocker panel 210 . Beamlet portion 105 4 of ion beam 105 is incident on and received by pixel 220 1 at an incident angle. In this example, each of the Faraday pixels 220 1 and 220 2 detects the current density of the incident ion beam and the detector determines the incident angles in accordance with Equation 1 above.
FIG. 3C is a side view of detector assembly 116 illustrating the distance d between blocker panel 210 and array 220 . In particular, distance d is measured from first surface 210 a of blocker panel 210 to first surface 220 a of array 220 . Support posts 240 1 and 240 2 are disposed between first surface 220 a of array 220 and second surface 210 b of blocker panel 210 . Each of the support posts may extend into respective bores (not shown) in blocker panel 210 . Alternatively, support posts 240 1 and 240 2 may be adjustably configurable to vary the distance d between blacker panel 210 and array 220 . Faraday bodies 2211 . . . 221 N extend from array 220 in order to prevent the beamlets of beam 105 which enter pixels 220 1 . . . 220 N from escaping and thereby detecting the received beam current.
FIG. 4 is a flow diagram illustrating an exemplary method 300 of monitoring uniformity of an ion beam in an ion implantation system. At step 310 , a target work piece is moved away from the ion beam and the detector assembly replaces the work piece to tune a desired implant profile. The detector is provided with a plurality of pairs of Faraday pixels to detect beam currents incident on the pixels. At step 320 , the detector assembly is moved horizontally through the ion beam. The current values of the beam incident on each of the pairs of Faraday pixels are recorded and stored at step 330 . For example, the current associated with detector 220 1 is recorded and stored and the current associated with the corresponding other of the pair of detectors 220 2 is recorded and stored. At step 340 , the position of the detector assembly for each of the current values in step 330 is recorded. The positions of the current measured at step 340 is adjusted to compensate for the distance between the detector pairs at step 350 . In other words, the detected currents will have positions that differ by the horizontal separation of each of the detectors in a pair. Once the detector assembly has passed completely through the ion beam at step 360 , the assembly is stopped and the beam angles are calculated. In particular, the angle of incidence of the beam on each pair of the plurality of pairs of detectors is calculated at step 370 using the formula A=ArcTan(((Ia−Ib)*w)/((Ia+Ib)*2d)) where A is the incident angle, Ia and Ib are the beam currents measured at a first and second of a pair of Faraday pixels, ‘w’ is the width of a particular one of the array of Faraday pixels and d is the distance from a blocker panel 210 to the Faraday array 220 . This calculation at provides a two dimensional array of angles in the Y direction based on the number of detectors in the X direction based on the number of current measurements performed as the detector assembly 116 moved across the ion beam. The angles of incidence are analyzed to determine the uniformity of the ion beam at step 380 . At step 390 , the beam current is adjusted based on the two dimensional array of angles calculated by adjusting the lenses and magnets to obtain the desired beam profile. This procedure may be repeated until the array of angles is acceptable indicating that the lenses and magnets in the ion implanter is appropriate for the given profile.
While the present invention has been disclosed with reference to certain embodiments, numerous modifications, alterations and changes to the described embodiments are possible without departing from the sphere and scope of the present invention, as defined in the appended claims. Accordingly, it is intended that the present invention not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof. | In an ion implanter, a detector assembly is employed to monitor the ion beam current and incidence angle at the location of the work piece or wafer. The detector assembly includes a plurality of pairs of current sensors and a blocker panel. The blocker panel is disposed a distance away from the sensors to allow certain of the beamlets that comprise the ion beam to reach the sensors. Each sensor in a pair of sensors measures the beam current incident thereon and the incident angle is calculated using these measurements. In this manner, beam current and incidence angle variations may be measured at the work piece site and be accommodated for, thereby avoiding undesirable beam current profiles. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation of application Ser. No. 12/561,468, filed Sep. 17, 2009, which is a divisional application of application Ser. No. 10/518,478, filed Jul. 26, 2005, which is a 371 of PCT Application No. PCT/AU2003/000778 filed Jun. 20, 2003, which claims priority from Australian Patent Application No. PS3090/02 filed Jun. 20, 2002, which applications are incorporated herein by references.
FIELD OF THE INVENTION
[0002] The present invention relates to a cover for a substrate, and in one form a cover for use with a microscope slide.
BACKGROUND OF THE INVENTION
[0003] Microscope slides are commonly used to view samples of material under a microscope. The samples may contain human tissue, and may require treatment such as staining, so that properties of the sample can be identified. Other materials such as DNA, RNA, or proteins may be included on the slide.
[0004] It is common for several reactions to be undertaken on a sample on a slide. Once the reactions have taken place the slide may be viewed under a microscope. Performing the reactions on the slide can be difficult to automate, as the tissue samples require careful preparation and certain reactions require carefully controlled environments.
SUMMARY OF THE PRESENT INVENTION
[0005] In accordance with the present invention, there is provided a cover for a substrate including:
[0000] a body defining a cavity, for positioning over the substrate to form a reaction chamber; and
a projection extending from the body to define a fluid reservoir, when the cover is fitted to the substrate, the fluid reservoir being in fluid communication with the cavity.
[0006] Preferably the cavity extends the full width of a sample holding region on the substrate.
[0007] Preferably, a protrusion extends from the projection, to assist in wicking fluid into the reservoir.
[0008] Preferably, the reservoir is defined between the projection, which is spaced from the substrate, and legs located at sides edge of the cover.
[0009] In one form the projection is formed from two sections, the first section is angled at least at substantially 60° relative to the cavity and the second section is angled at least at substantially 15°.
[0010] In one form, the cover further includes a second reservoir, at an opposite end of the cover.
[0011] Preferably wall portions are located at the edge of the cover, surrounding the cavity on two or more sides.
[0012] In one form the legs extend along the sides of the cover to form the wall portions.
[0013] In a preferred form, the cover includes a locator for controlling and locating the cover, the locator being arranged at an end of the cover opposite the projection.
[0014] In one form the cavity extends to an end edge of the cover adjacent the locator.
[0015] In one form the cover is supported on the substrate by the wall portions.
[0016] Preferably, the cover is made from a polymer material.
[0017] In one form the cavity includes a coating of reduced surface roughness than the polymer material.
[0018] In another form the cavity includes a coating with reduced porosity.
[0019] In another form the cavity has one or more coatings.
[0020] Preferably a first coating is a material having similar properties to the material of the slide.
[0021] Preferably the first coating is silicon dioxide.
[0022] Preferably a second coating is placed intermediate a first coating to provide improved contact properties between the cover and first coating.
[0023] Preferably, the cover has associated wing structures that allow the cover to be engaged and pivoted relative to the substrate so as to open the reaction chamber and allow the slide to be cleared of fluid.
[0024] In another aspect, there is provided a combination of a substrate and a cover, as described above, wherein the cavity of the cover is arranged to face the substrate so as to form a reaction chamber.
[0025] In yet another aspect, there is provided a method of treatment of a sample on a sample holding region of a substrate, including locating a cover, as described above, over the substrate, so that the cavity of the cover faces the substrate to form a reaction chamber over the sample holding region, and depositing fluid into the fluid reservoir to allow the fluid to be drawn into the reaction chamber, as required.
[0026] Preferably, the method further includes sliding the cover relative to the substrate to vary a degree of overlap between the cover and the sample holding region, which results in a corresponding variation in the reaction chamber volume.
[0027] Preferably, the method further includes sliding the cover relative to the substrate until wing structures associated with the cover are engaged and lifted relative to the substrate to pivot the cover into an open condition, and allow fluid to drain from the reaction chamber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The invention is described, by way of non-limiting example only, with reference to the accompanying drawings, in which:
[0029] FIG. 1 shows an example of a microscope slide;
[0030] FIGS. 2 ( a )-( c ) show top, side and bottom views of a first example of a cover for a slide;
[0031] FIG. 3 shows a perspective view of the cover of FIG. 2 ;
[0032] FIGS. 4 ( a )-( c ) show further views of the cover of FIG. 2 located on the slide of FIG. 1 ;
[0033] FIG. 5 is a perspective view of the cover and slide arrangement of FIG. 4 , showing a cutaway section of the cover;
[0034] FIG. 6 shows a schematic cross section of the cover and slide of FIG. 5 ;
[0035] FIG. 7 shows a perspective view of a tray adapted to locate covers and slides;
[0036] FIGS. 8 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0037] FIGS. 9 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0038] FIGS. 10 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0039] FIGS. 11 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0040] FIGS. 12 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0041] FIGS. 13 ( a ) and ( b ) shows schematic top and sectional side views, respectively, of a further example of a cover;
[0042] FIGS. 14 ( a ) and ( b ) show top and bottom perspective views, respectively, of a further example of a cover;
[0043] FIG. 15 shows a schematic side view of a nose portion of a cover;
[0044] FIGS. 16 ( a ) and ( b ) show schematic top and sectional side views, respectively, of a further example of a cover;
[0045] FIG. 17 shows a schematic side view of a further example of a nose portion of a cover;
[0046] FIG. 18 shows the cover of FIG. 2 mounted to the tray of FIG. 7 ;
[0047] FIGS. 19 ( a )-( c ) shows the cover of FIG. 2 in various positions over the slide of FIG. 1 ; and
[0048] FIGS. 20( a ) and ( b ) show a bottom perspective view and enlarged partial perspective view, respectively of a modified cover.
DETAILED DESCRIPTION
[0049] A microscope slide 1 is shown in FIG. 1 as including an upper surface 2 containing a sample 3 . The slide 1 is identified by a unique bar code 4 . The sample 3 , such as a thinly sliced tissue section, is located on the slide 1 in a sample holding region 5 , which needs to be covered by a cover, such as shown in FIG. 2 , for subsequent application of test fluids and the like.
[0050] FIGS. 2 ( a )-( c ) and FIG. 3 show a cover 10 as having a body 12 , a fluid receiving zone 14 , a locating means 16 and a cavity 18 on an underside face 19 . Surrounding the cavity 18 on two sides is a wall portion 20 . At one end of the cover 10 , the wall portion 20 joins with legs 21 which extend upwardly and away from the face 19 . The legs 21 are spanned by a projection 13 which defines a fluid reservoir 17 , between an underside of the projection and the legs 21 .
[0051] The cover 10 is shown fitted to a slide 1 in FIGS. 4 and 5 . The fluid reservoir 17 is shown most clearly in FIG. 4 ( c ) where a detailed view of part of a section A-A taken across the cover 10 and slide 1 is illustrated. The projection 13 , with leg 21 at either end, is raised relative to the slide 1 , to form a volume capable of holding fluid dispensed onto the slide 1 . In this way fluid reservoir 17 enables fluid dispensed onto slide 1 to be held until required, without spilling off an edge of the slide. The projection 13 further assists in spreading the fluid across the full width of the cavity 18 .
[0052] The overlap of the cavity 18 with the slide 1 forms what may be described as a reaction chamber, as illustrated in FIG. 6 . The cavity may vary according to application, typically from 20-200 microns. The wall portion 20 is adapted to support the cover on the slide 1 . The cavityed face 22 , wall portion 20 and sample holding region 5 of a slide 1 form a reaction chamber 24 when the cover 10 is placed at least partially over the sample holding region 5 .
[0053] The fluid reservoir 17 is typically sized to be larger than the volume of the reaction chamber 24 , for example 150% of the volume of the reaction chamber. This provides sufficient volume of fluid to fill the reaction chamber completely, while allowing some excess to flush the chamber, and an amount to be retained in the fluid reservoir to provide a reservoir for evaporation.
[0054] Clamping forces may also be applied to the cover once loaded onto the slide, and these forces are designed to provide a seal between the wall portions 20 and the upper surface of the slide 1 . This is to restrict fluid leakage from the side of the cover. In one example (not shown) the wall portions may have an additional member to assist sealing of the wall portions with the upper surface 2 of the slide 1 . This additional member may be a softer polymer or rubber material.
[0055] The cover 10 also includes engaging surfaces in the form of wings 26 . The wings 26 are adapted to engage ramps 28 of a tray 21 shown in FIG. 7 , to thereby lift the cover clear of the surface of the slide 1 . An example of the wings lifting the cover free is shown more clearly in FIG. 18 . The cover 10 may be controlled by an arm (not shown) moving the locating means 16 . The cover 10 may be placed in a number of positions over the slide, exemplified by the positions of the cover relative to the slide shown in FIG. 19 . In FIG. 19( a ), the cover 10 is in an open position relative to the slide 1 , as the sample is exposed and open. FIG. 19 ( b ) shows the cover in a partially closed position, and FIG. 19 ( c ) shows the cover in a fully closed position, where the sample is completely covered by the cover and is therefore wholly contained within the reaction chamber 24 . The reaction chamber formed by the cover and cavity 18 , as shown in FIG. 5 , extends over most of the slide 1 . However it is possible that the sample may be placed more towards the end of the slide distal from the bar code 4 , and therefore a smaller reaction chamber 24 is required. Reducing the size of the reaction chamber 24 reduces the amount of fluid required to fill the chamber, which can be important where expensive or scarce fluids are used. It is possible to form a smaller reaction chamber with the cover 10 , by only covering a portion of the slide 1 with the cover 10 . This position is shown in FIG. 19 ( b ).
[0056] Variations in cover constructions are schematically shown in FIGS. 8-17 . In FIGS. 8-17 , only the front segments of the covers are shown, and the locating means 16 have been omitted from view for clarity and like parts are denoted by like reference numerals.
[0057] In FIG. 8( a ) a cover 10 is shown having a body 12 , projecting legs 21 , a protruding section 13 and an indent 30 . The projecting legs 21 either side of the body 12 form a fluid receiving zone 14 . When placed onto a slide, fluid may be dispensed into the fluid receiving zone, where it spreads in a circular fashion to contact the protruding section 13 . The indent 30 allows the fluid to contact a wider portion of the protruding section 13 than if the front edge of the protruding section was straight (as shown in FIG. 9) . Once the fluid is in contact with the protruding section 13 , it wicks across the width of the cavity 18 . If suction is applied at the rear of the cavity, or the cover is moved along the slide from an open position to a more closed position, then the fluid begins to fill the cavity 18 . When the cavity 18 has moved across the sample 3 , it forms the reaction chamber 24 as the fluid may react with the sample 3 .
[0058] FIGS. 9 ( a ) and ( b ) show a more simple construction of a cover 10 that may be used in some circumstances. The operation of the cover 10 is the same as the operation of the cover 10 in FIGS. 8 ( a ) and ( b ).
[0059] FIG. 10s ( a ) and ( b ) show a cover 10 having a body 12 with projecting legs 21 . A protruding section 13 and a bar 31 surround a fluid receiving zone 14 for receiving fluid. The fluid may be dispensed onto the protruding section 13 , where it flows down and onto the slide surface 2 . The protrusion 13 and bar 31 cause the fluid to spread across the width of the cavity 18 , enabling the cavity to be filled with fluid.
[0060] The covers 10 of FIGS. 11 , 12 and 16 operate in similar ways to those described above.
[0061] In relation to all of the above-described covers, it should be appreciated that the covers are generally 25 mm across, and the cavity 18 is typically only 20-200 micrometres high. As such, overall fluid dispense volumes may be in the order of 20-300 microlitres.
[0062] FIG. 13 ( a ) shows another cover 10 having a body 12 , legs 21 and a fluid dispenser 100 dispensing fluid 102 onto the slide 1 . In FIG. 13 ( a ), the fluid 102 has already been dispensed, and has formed a fluid reservoir in the fluid reservoir 17 . The schematic Figure shows a typical wicking pattern formed by the fluid as it contacts the cover 1 . In FIG. 13 ( b ), the fluid is just being dispensed onto the projection 13 . In the volumes dispensed, the fluid forms a pool of comparable size to some of the cover features. Not only does the fluid flow forward of the cover as shown in FIG. 13 ( a ), but it also flows under the cover to at least partially fill cavity 18 . As mentioned above the fluid may be drawn into the cavity further by movement of the cover over the slide or suction applied to the rear of the cavity 18 .
[0063] FIGS. 14 ( a ) and ( b ) shows a further embodiment of a cover 10 where like reference numerals are again used to denote like ports. The cover has a fluid reservoir 17 , a projection 13 , and a protrusion in the form of nib 15 . Fluid may be deposited directly on the nib 15 so that the fluid rolls over the projection 13 into reservoir 14 , and to the cavity 18 , as required. If fluid is placed too far ahead of the cover, there are circumstances that may cause the fluid to reach the edge of the slide before wicking across the width of the cavity 18 . It has been found that using the projection 13 causes the dispensed fluid to contact the covertile and spread along the full width of the cavity 13 , due to the positive attraction of the covertile and the fluid. The capillary forces in the cavity cause the fluid to spread out, and the reservoir holds sufficient fluid to ensure that fluid dispensed onto the slide at least fills the cavity 18 . The nib 15 is useful in that if the pipette is not placed to dispense the fluid accurately onto the slide, and for example misses a few millimetres in front of the projection, the nib 15 will be likely to contact the fluid, which will be drawn to the protrusion and into the reservoir. This assists in reducing bubble or void formation within the cavity. The nib 15 may extend approximately 1-5 mm from the projection 13 .
[0064] FIG. 17 shows an example of how fluid spreads across a slide when deposited in front of a cover 50 . A variety of profiles for the underside of a projection 15 may be employed.
[0065] In use, a cover 10 is placed on a slide 1 , as shown in FIGS. 4 , 5 and 6 to cover the sample 3 . The slide 1 will typically be in a tray 21 as shown in FIG. 7 , said tray 21 able to hold, for example, 10 slides and covers of the examples shown. The tray 21 may then be placed into a biological reaction apparatus, such as that disclosed in Australian Provisional Patent Application No. PS3114/02 by the same applicant, titled “Method and Apparatus for Providing a Reaction Chamber”, filed 20 Jun. 2002, and its associated international patent application, filed 20 Jun. 2003, the contents of which are hereby incorporated by reference.
[0066] Once the tray 21 is loaded into the apparatus (not shown) the slides 1 are held in position, typically at an angle of 5 degrees to the horizontal as shown schematically in FIGS. 13 ( b ), 15 or 17 . The cover 10 is then moved by an arm (not shown) engaging the locating means 16 . Typically, during a sequence referred to as an “open fill”, the cover 10 is moved longitudinally along the surface of the slide 1 until the sample 3 is exposed. A fluid is then dispensed by a dispensing means 100 such as a probe attached to a pump, onto the fluid receiving zone 13 (as shown in FIG. 13 ( b )). The amount of fluid dispensed is typically sufficient to fill the reaction chamber 24 . The use of the cover 10 with this fill mechanism or methodology allows a small volume of fluid to be uniformly distributed across the reaction chamber 24 . Distributing the fluid across the reaction chamber 24 evenly and without bubbles or air spaces allows reactions to take place on the sample 3 with greater consistency. Also, dispensing fluid into an empty receiving zone where the reaction chamber already contains fluid causes the fluid within the chamber to be replaced by the fluid in the receiving zone minimising mixing of the fluid in the reaction chamber and newly dispensed fluid. The dimensions of the reaction provide a smooth flow of fluid from the reaction chamber such that there is little mixing of the fluids. This is advantageous as it allows a previous fluid to be replaced accurately, with minimal original fluid remaining to contaminate later fluids or reactions. This reduces the number of washes required to clear the reaction chamber 24 .
[0067] The volume of fluid in a reaction chamber 24 may be, for example 150 microlitres or less, although volumes may vary depending on the application and the reaction chamber dimensions.
[0068] The reaction chamber 24 is able to retain fluid due to the surface tension of the fluid, unless additional fluid is added to the fluid receiving zone, or suction is applied (typically through reduced air pressure) at the end of the slide opposite the fluid receiving zone. The reaction chamber may be filled as it is formed by the cover 10 being moved along the surface of the slide 1 to cover the sample holding region 52 . Alternatively, the reaction chamber may be filled without the cover being moved relative to the slide, due to the process of capillary wicking of dispensed fluid into the reaction chamber.
[0069] In the present examples the cover may be clamped to the slide when not in motion or retracted for an initial fill. The clamping mechanism (not shown) places force around the edge of, for example, cover 10 adjacent the wall portions 20 to locate the cover 10 with respect to the slide 1 during a reaction.
[0070] During the withdrawal of the cover 10 from the slide 1 it is sometimes desirable to remove the cover from contact with the slide. In order to accomplish this, wings 26 engage the ramps 28 to lift the cover clear of the slide. This causes the cover 10 to lift off the slide 1 to prevent fluid contact between the slide 1 and cover 10 . In this way the slide can be cleared of virtually all fluid.
[0071] Parts of the cover may have different material properties compared to the properties of the material of the cover body 12 , which is typically plastic. In one example (not shown) the cavity may have different material properties, in order to provide a reaction chamber 24 with certain material properties. A clear plastic material has been found to be suitable for the body 12 of the cover 10 , to provide suitable mechanical properties such as reasonable strength and rigidity. The cover needs to be sufficiently strong to be moved while clamping forces are applied to the cover, as the clamping forces assist in providing a sealing surface between the walls 20 of the cover 10 and the upper surface of the slide 1 . The cover may be moved to empty or fill the chamber, or also, to promote fluid movement within the reaction chamber to assist a reaction.
[0072] The cover should ideally have some flexibility, as it is desirable that upon application of the clamp, the cavityed face should deflect somewhat. This has been found to assist in moving the fluid within the reaction chamber and therefore increases the exposure of the sample to the fluid.
[0073] Other properties of the cover 10 include the ability to restrict the heat loss from the surface of the slide 1 . Typically the slide will be mounted on a heated block, and the cover will be placed over the sample on the slide. Heating the slide heats the sample and the fluid in the reaction chamber. If there is excessive heat loss from the cover 10 it is difficult to regulate the temperature of the fluid by heating the slide 1 . Further, there may be an excessive temperature gradient across the reaction chamber 24 , which is undesirable.
[0074] The cavityed face 19 , as shown in FIG. 2 , may have different surface properties to the rest of the cover. It has been found to be desirable to have similar material properties for the upper surface of the slide 2 and the cavity 18 . In one example, it is possible to coat the surface of the cavity with a material 77 (shown in FIG. 6 ), such as silicon dioxide. This coating may be approximately 110 nm thick. The coating provides a surface with material properties similar to that of a glass slide. It has also been found that there are benefits in applying a thin layer 79 (for example 0.5-6 nm) of Chromium Oxide (Cr2O3) to the cavity before applying the silicon dioxide layer. This application of an intermediate layer between the silicon dioxide and plastic provides better adhesion and better thermal expansion properties for the cavity. Further, coatings in general may be used to improve the flatness of the cavity (which reduce nucleation sites and therefore bubble formation at high temperatures). The coatings may be used to modify the capillary flow characteristics of the fluid within the reaction chamber, create an impermeable barrier for gas or liquid between the cover and fluid in the reaction chamber, or provide a chemically inert surface.
[0075] In another example, it is possible to replace the cavityed face 19 with a glass insert supported by the plastic body 12 of the cover 10 . It may also be possible to change the surface properties of the plastic by plasma discharge.
[0076] The covers shown in the examples may be used at temperatures approaching 100 degrees Celsius, especially when used for in-situ hybridisation reactions. At higher temperatures, the fluid evaporates and bubbles are produced. The heating may also cause the cover to bow—the cavity surface is hotter than the top of the cover and expands more, causing the cavity surface to ‘sag’ towards the slide. This helps to remove the bubbles, as the fluid wants to occupy the smaller spaces more than the bubbles do. The bubbles congregate at the ends of the cavity, and must be allowed to escape.
[0077] Experiments have demonstrated that a chamfer at the end of the cavity reliably allows the bubbles to escape to atmosphere. The existing reservoir 17 can be redesigned as illustrated in FIG. 20 , where a modified cover 60 , similar to that shown in FIG. 14 , is shown with a chamfer 61 to assist in releasing bubbles, without affecting the even fluid flow through the cavity 18 . The chamfer forms a first angled section 62 at about 60° relative to the cavity and slide surface.
[0078] Fluid evaporation rate is, however, directly linked to the surface area of the fluid exposed to atmosphere—a larger surface area will evaporate faster, and require more frequent replenishment. If the bubble escape angle is steep, the evaporation rate will increase.
[0079] This problem can be overcome by using two angles—a shallow angled section at, say, 15° between the cavity and the chamfer, to minimise evaporation, leading into the steeper angle for bubble release, which also serves to increase the volume of the reservoir.
[0080] The cover 60 is also provided with a second, identically shaped reservoir 63 at an opposite end thereof. The second reservoir 63 can also be used to replenish fluid within the cavity during heating and to allow bubbles to escape. The second reservoir 63 thereby allows for increased control of fluid conditions within the reaction chamber.
[0081] The embodiments of FIGS. 14 and 20 are considered to represent what is currently believed to be the best known method of performing the cover aspect of the invention. | A cover for a substrate including: a body defining a cavity, for positioning over the substrate to form a reaction chamber; and a projection extending from the body to define a fluid reservoir, when the cover is fitted to the substrate, the fluid reservoir being in fluid communication with the cavity. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of commonly owned U.S. patent application Ser. No. 07/973,236 filed on Nov. 10, 1992, now U.S. Pat. No. 5,284,503, in the name of John A. Bitler et al and entitled "Process for Remediation of Lead-Contaminated Soil and Waste Battery Casings", the entire content of which is expressly incorporated by reference hereinto.
FIELD OF INVENTION
The present invention relates generally to a process for the remediation of lead-contaminated soil and waste battery casings. More specifically, this invention relates to a novel process whereby a mixture of lead-contaminated soil and battery casings may be pyrolyzed in a plasma arc furnace so as to volatilize the battery casings to form a combustible CO gas that is then supplied as a primary fuel to a conventional smelting furnace. A major proportion of the lead contaminant is likewise volatilized and transferred along with the combustible gas to the smelting furnace where it can then be subjected to conventional lead-recovery techniques. The soil, on the other hand, forms a vitrified slag in the plasma arc furnace and thereby serves as a non-toxic and non-leachable host matrix for any minor proportion of lead that is either not volatilized or removed from the plasma arc furnace in a molten form.
BACKGROUND AND SUMMARY OF THE INVENTION
The safe treatment and disposal of all waste materials is demanded in most developed nations. In this regard, there is a growing demand on industry by environmentalists and government agencies to alleviate potentially toxic and/or contaminated waste disposal sites that were employed for many years prior to the public's heightened environmental concerns and the enactment of environmental legislation.
For example, a number of now defunct lead-acid battery recycling sites were operated where lead was reclaimed from spent lead-acid batteries. At most such lead-acid battery recycling sites, the primary operation consisted of breaking the battery case, draining the spent acid, and separating the battery cases from the commercially valuable lead to be recycled. The broken battery cases, which were at that time formed of a non-recyclable, hardened rubber material known in art parlance as "ebonite", were of no commercial value and were thus typically discarded as landfill waste. However, it is now known that these discarded battery cases in landfills nonetheless were contaminated with sufficient quantities of lead that could detrimentally affect the environment.
Various techniques have been proposed for the remediation of landfills containing lead-contaminated waste lead-acid battery casings. For example, The U.S. Bureau of Mines has proposed a chemical reclamation process for waste lead-acid battery casings whereby battery casing particles are carbonized by treatment in a sodium or ammonium carbonate solution followed by acid washing with nitric acetic or flurosilicic acids. See, "The Hazardous Waste Consultant", September/October 1991, pages 1.22-1.24.
Simply immobilizing the lead contamination at landfills has been identified as one possible option recently by Royer et al, "Control Technologies for Remediation of Contaminated Soil and Waste Deposits at Superfund Lead Battery Recycling Sites", Journal of Air & Waste Management Association, Volume 42, No. 7, pgs. 970-980 (July 1992). However, the authors indicate that immobilization by vitrification would be unsuitable due to the combustible nature of the casings.
It would therefore undoubtedly be desirable for a process to be proposed whereby landfill materials containing both lead-contaminated soil and waste lead-acid battery casings could be treated so as to ameliorate the environmental concerns posed by such landfill materials. Furthermore, it would be desirable if a system was provided which could be readily transported to a landfill site of waste lead-acid battery casings so that remediation of the lead-contaminated soil could be accomplished on-site (i.e., as opposed to shipping the lead-contaminated soil to an off-site remediation facility). It is towards providing such processes and systems that the present invention is directed.
Broadly, the present invention is especially characterized in the treatment of lead-contaminated soil and battery casings using a plasma arc furnace which pyrolyzes the soil and waste battery casings so as to form a vitrified slag and a combustible gas, respectively. The combustible gas (which contains predominantly carbon monoxide) along with volatilized heavy metals (of which lead predominates) is directed to, and used as, a primary fuel by a conventional lead smelting furnace. The volatilized lead that is entrained in the combustible gas is thus transferred thereby to the lead recovery and environmental protection/control equipment associated with the smelting furnace. The soil, on the other hand, is converted into a non-toxic (i.e., according to the Toxicity Characteristic Leaching Procedure (TCLP) published in the Federal Register on Mar. 29, 1989, the entire content of which is expressly incorporated hereinto by reference) vitrified slag by the plasma arc which may be crushed and used as a commercial material (e.g., roadway aggregate, asphalt filler material or the like) or simply transferred to a landfill where it poses no environmental threat.
Furthermore, such plasma arc furnace and associated process equipment (e.g., generators, time scrubbers, and the like) may be mounted on mobile platforms (e.g., truck beds, rail cars, and the like) so as to be transportable to a battery casing landfill. The plasma arc furnace and associated equipment may then be operatively interconnected with one another and operated on-site until the landfill remediation is completed, significantly, the combustible gas which is generated in the plasma arc furnace may be employed as a fuel for electrical generators which supply the electrical power necessary for the plasma arc furnace. As such, the transportable on-site remediation system of this invention can be self-contained--i.e., will not necessarily need any externally supplied utilities.
Further aspects and advantages of this invention will become apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Reference will hereinafter be made to the accompanying drawings wherein like reference numerals throughout the various FIGURES denote like elements, and wherein
FIG. 1 schematically depicts a flow diagram for a particularly preferred process scheme according to this invention; and
FIG. 2 is a schematic representation for a transportable, on-site remediation system according to this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The accompanying FIG. 1 depicts a particularly preferred process flow diagram according to the present invention. In this connection, although the process depicted in the accompanying FIG. 1 operates on a batchwise basis, continuous processing of the lead-contaminated soil/battery casings according to this invention could equally be envisioned.
The soil and battery casing constituents of the landfill material are separated from one another by any suitable mechanical separatory technique (e.g., differential specific gravity apparatus, vibratory or non-vibratory screens, and the like) schematically identified as separator 10 in FIG. 1. The soil component is transferred to a soil hopper 12, while the battery casing component is transferred to a casing hopper 14. Prior to being deposited into the hopper 14, however, the casings are most preferably crushed to a suitable size (e.g., average particle size between 0.375 inch to 0.5 inch) by a crusher 16.
The soil and casings hoppers 12, 14 are provided with flow control valves 12a, 14a, respectively, so as to meter a batch charge having a predetermined ratio of soil to casings to the input hopper 18a of plasma arc furnace 18. Control of the valves 12a, 14a so as to meter the appropriate amounts of soil and casings, respectively, can be accomplished in any convenient manner, such as, by load scales associated with the hoppers 12, 14 and/or the furnace 18 which supply an input signal to a flow controller for the valves 12a, 14a.
It will be understood that the battery casings which are typically associated with lead-contaminated landfills are formed of a hardened rubber composite material conventionally called "ebonite". The composite hardened rubber material can be a synthetic rubber (e.g., styrene-butadiene cross-linked with sulfur) having upwards of 40% of a carbonaceous material, such as anthracite coal or carbon black as a filler material. However, the present invention may equally be applied to landfills which may contain waste battery casings formed from a more modern polyolefinic resin (e.g., polypropylene).
The battery casings may be characterized as a solid organic material, whether formed of the discontinued ebonite material or the more modern polyolefinic material. It will therefore be understood that the greater the amount of casings in the batch charge to the plasma arc furnace 18, the greater the amount of combustible CO gas that will be produced by pyrolyzing the casings. Thus, since the combustible gas that is generated by pyrolyzing the casings is intended to be used as the primary fuel for a conventional smelting furnace system (as will be described in greater detail below), the preferred ratio of soil to casings is determined in large part by the fuel requirements of the smelting furnace system. By way of example,a smelting furnace (or other equipment intended to combustibly consume the combustible gas generated by the plasma arc furnace according to this invention) having a fuel requirement of 30×10 BTU/hr will typically dictate a soil to casings weight ratio of between about 7:1 to 5:1 being fed to the plasma arc furnace 18 in order to supply 100% of such fuel requirement.
The particular type of plasma arc furnace 18 which is employed in the practice of this invention is not particularly critical, provided that it can pyrolyze the waste battery casings. Thus, either transfer or non-transfer types of plasma arcs may be employed. Similarly, the ionizing gas that may be employed to generate the plasma arc can be any that is conventionally used for such purpose, such as, compressed air, nitrogen and/or argon.
In the accompanying FIG. 1, the plasma arc furnace 18 is depicted as being a conventional batch non-transfer plasma arc type. However, as indicated previously, a transfer plasma arc type furnace could be employed, if desired. Also, the furnace 18 could be continuously operated, e.g., by providing a continuous supply of soil/casings into the furnace, and continuously removing the formed vitrified slag therefrom.
The batch plasma arc furnace 18 depicted in the accompanying FIG. 1 most preferably includes a hydraulic feeding ram 18b which serves to force the batch charge transferred from the hoppers 12 and 14 into the crucible 18c where it is pyrolyzed by the torch 18d. The plasma torch 18d is connected to a suitable control system 18e and direct current power supply 18f (preferably rated at at least about 350 volts and 400 amps) so as to generate a plasma flame which contacts the batch charge (noted by reference numeral 18g) in the crucible 18c.
It may be desirable to include a flux material with the mixture of soil and casings charged to the furnace 18, particularly when acidic soil is encountered, in order to reduce the soil melting point and thereby enhance its vitrification. Suitable fluxes may be, for example, blast furnace slag and/or limestone, and may be used in relatively minor quantities. e.g., up to 10 wt. %, more preferably, between about 5 to 10 wt. % of the furnace charge. In addition, the charge to the furnace can conveniently be converted to reduction conditions by the addition of a carbon source (e.g., coke breeze, coal or the like) in suitable quantities.
In order to ensure that the lead-contaminated battery casings are completely pyrolyzed by the flame of the plasma arc torch 18d, it is preferred that the batch charge 18g be agitated during its pyrolysis. Agitation can be accomplished utilizing mechanical agitators within the crucible 18c. However, since the temperature of the flame created by the plasma arc torch 18d, is typically between 4,000° to 8,000° C. or greater, agitation of the batch charge 18g may conveniently be obtained by oscillating the plasma arc torch 18d itself using suitable motor and mounting structures for the torch 18d. Oscillation of the plasma arc torch 18d will thus direct the flame along the surface of the batch charge 18g and thereby create internal flow agitation therewithin. Alternatively, agitation of the molten furnace charge may occur naturally by virtue of electrical conductance vectors of the torch.
The combustible gas which results from pyrolyzing the battery casings and the vaporized lead (as well as other vaporized metal contaminants in the soil/casings mixture) entrained thereby arc transferred via line 20 to the smelting furnace system SFS. The vitrified slag, on the other hand, may be transferred via line 22 to a crusher 24 so that it may be broken into a particulate of selected size. The vitrified slag is non-toxic (i.e., since it does not test out of limits according to Toxicity Characteristic Leaching Procedure) and provides a host matrix for lead (or any other heavy metal) not volatilized during plasma arc furnace pyrolysis. Thus, the vitrified slag may be returned to a landfill without risk of environmental concerns or may be transferred to a storage site for later use as a commercial product (e.g., roadway aggregate, asphalt fill material, and the like).
As noted previously, the combustible gas resulting from pyrolyzing the battery casings is transferred to a smelting furnace system SFS which is conventionally employed in lead-smelting operations. The smelting furnace system SFS thus typically is comprised of a smelting furnace 30 (which may be a reverbatory type furnace as is shown in the accompanying FIGURE) and downstream environmental control equipment, such as a cooler section 32 (which condenses any volatilized lead not recovered in the furnace 30), dust collector section 34 (which traps finely divided lead-contaminated particulates), and a final gas scrubbing section 36. The particulates recovered from the cooler and dust collector sections 32. 34, respectively, are recycled to the inlet of the smelting furnace 30 to recover substantially all lead.
The smelting furnace 30 is fueled primarily by the combustible gas formed by the pyrolysis of the battery casings in the plasma arc furnace 18. However, there may be instances where the thermal capacity of the combustible gas transferred via line 20 is insufficient to fuel the smelting furnace properly. Thus, the smelting furnace is provided according to this invention with a temperature probe 40 which measures the temperature in the furnace's combustion chamber. The temperature signal supplied by the temperature probe is fed to a fuel flow controller 42 which compares the measured temperature against a temperature set-point and issues appropriate output signals to flow control valves 44, 46, associated with combustible gas line 20 and with a natural gas supply line 48, respectively. As a result, when the temperature probe 40 detects inadequate temperature existing within the combustion chamber of the furnace 30 (indicative of inadequate combustion properties and/or inadequate flow of combustible gas introduced via line 20), the fuel flow controller 42 will then increase the flow of natural gas to the furnace 30 from supply line 48 so as to supplement flow of combustible gas in line 20. In such a manner, the furnace 30 is maintained in continuous operation, even though the plasma arc furnace (and its lead-contaminant remediation functions) are conducted in a batch-wise manner.
As noted briefly above, the remediation process described in connection with FIG. 1 may be embodied in a mobile system which can be transported easily to a waste lead-acid battery casing landfill and operated onsite until the landfill remediation is complete. A particularly preferred mobile remediation system 100 is depicted in accompanying FIG. 2. As is shown, the remediation system 100 will necessarily include a plasma arc furnace 18 as described above. However, in the interests of mobility and self-contained operation, the plasma arc furnace 18 will be supplied with electrical power by one or more electrical generators 102a-102c driven by internal combustion engines 104a-104c, respectively. In this regard, the electrical power will be directed to a control unit CU so as to control the supply of electrical power generated by the generators 102a-102c to the plasma arc furnace 18.
The combustible gas which is generated by the plasma arc furnace 18 may first be passed through a heat exchanger 105 and then through a suitable filtration sub-system 106 so as to remove volatilized lead contaminants entrained in the gas. The scrubber sub-system 106 may thus include a cooler, dust collector and flue scrubber to remove the volatilized lead contaminant from the stream of combustible gas discharged from the furnace 18. The combustible gas may then be provided as a fuel supply via lines 107 and 109 to one or more of the combustion engines 104a-104c (e.g., depending upon the power supply needs of the plasma arc furnace). In the event that the thermal content of the combustible gas generated by the plasma arc furnace 18 is insufficient in order to properly power the internal combustion engines 104a-104c, however, a supplemental fuel such as liquified natural gas, propane or the like from source 110 may be mixed with the combustible gas at valve 112 and then supplied to the internal combustion engines 104a-104c via line 109. In the event that the self-contained power supplied by the electrical generators 102a-102c is not needed on-site (i.e., due to the availability of on-site electrical power), then the valve 114 at the junction of lines 107 and 109 may simply be positioned so that the combustible gas is directed to an ignitor 116 which burns the combustible gas in the ambient atmosphere with an appropriate scrubber 117.
Cooling of the plasma arc furnace 18 in the system 100 shown in FIG. 2 is most preferably self-contained, that is, it is preferred that the plasma arc furnace 18 be cooled by readily transportable means. If a supply of water is readily available, then the cooling sub-system is most preferably comprised of a heat exchanger unit 120 having intake conduits 120a and associated pumps 120b to supply cooling water and discharge conduits 120c to return water to its source (which as depicted in FIG. 2, may be a natural body of water such as a stream, lake or the like).
The cooling water from the exchanger unit 120 is directed to an external cooling jacket (not shown) associated with the plasma arc furnace 18. Upon leaving the cooling jacket of the plasma arc furnace 18, therefore, the water may be directed to the heat exchanger 105 associated with the scrubber sub-system 106 to serve as a preliminary heat-exchange fluid with the significantly hotter combustible gas. The heated liquid will then be transferred to the soil preparation subsystem 124 where the heat may be employed to dry the lead-contaminated soil from the landfill introduced into hopper 124a. Thus, the outlet temperature of the water discharged from the soil preparation subsystem 124 will be less as compared to the inlet water temperature. As a result, this remaining heat may be extracted from the water discharged from the soil preparation subsystem 124 by heat-exchange with the cooling water taken from the supply by means of the heat exchanger unit 120. Water which is returned to the natural source will therefore not be at an appreciably high temperature which would cause environmental concerns for fish and/or wildlife in the vicinity of the remediation system.
As noted above, the soil/battery casing mixture will first be supplied to the soil preparation subsystem 124 where it will be dried, comminuted via crusher 128 and then supplied the plasma arc furnace 18 . After processing in the furnace, the now vitrified soil (termed "slag") will be transferred to a slag processing unit 120 where it will be crushed, screened and sized and the like. The resulting processed slag may then be returned to the landfill site and/or sorted by size in hoppers 130, 132 and collected for sale as a usable product (e.g., roadway aggregate, etc.).
The various units may be mounted onto mobil platforms as shown by the double dash line representations in FIG. 2. That is, the electrical power generation system may be mounted onto a mobile platform designated by double dashed line 140; the plasma furnace 18 and soil preparation subsystems 124/128 may be mounted on a mobile platform as noted by the double dashed line 142; the heat exchanger 105, scrubber 106 and slag processing units 120 may be mounted on a mobile platform 144; and the heat exchange system 120 mounted on a mobile platform 146. Of course, the number of mobile platforms and the individual unit operations supported thereby is dependent upon a variety of factors, for example, the size of the mobil remediation unit 100 and its processing capacity. Preferably, the mobil platforms 140, 142, 144 and 146 will be truck beds due to the relative ease of transporting the equipment overland and the ability to access remote landfill sites. However, as those in this art can appreciate, other means of self-contained mobility (e.g., rail cars) could likewise be employed.
Although the invention has been described above as being especially well suited to the remediation of soil containing waste lead-acid battery casings, it may usefully be employed in the remediation of landfill materials generally. That is, the present invention could usefully be employed in the remediation of landfills in which waste materials, such as waste paper and/or paperboard products, various metals, hydrocarbon fuels and/or chemical feedstocks, plastics materials or the like, are mixed with landfill soil.
Thus, while the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. | A mobile system for the remediation of a mixture of lead-contaminated soil and waste lead-acid battery casings includes a plasma arc furnace unit having a plasma arc torch which operates at a sufficiently elevated temperature to (i) convert the battery casings in the mixture into a combustible gas, (ii) volatilize lead contaminants which are present in the mixture and entrain the volatilized lead contaminants as a vapor in the combustible gas, and (iii) vitrify the soil, whereby lead contaminants that were present in the mixture are substantially removed therefrom. An internal combustion engine-driven generator supplies the plasma arc furnace with electrical power. In this regard, the internal combustion engine-driven generator receives the combustible gas from the plasma arc furnace as a fuel source in order to drive the generator. A lead-filtration unit is preferably interposed between the generator and the plasma arc furnace so as to receive the combustible gas generated by the plasma arc furnace and remove the entrained lead contaminants therefrom. A supply of secondary fuel gas (e.g., liquified petroleum gas, natural gas or the like) may optionally be supplied to the internal combustion engine-driven generator as a supplemental fuel together with the combustible gas generated by the plasma arc furnace. The various nit operations may be mounted for mobility (e.g., on truck beds, rail cars or the like) to permit transportation to a landfill in need of remediation. | 8 |
CROSS REFERENCE TO RELATED APPLICATION
The present application is the national phase of International Application No. PCT/CN2014/089647, titled “MEDIA FILE PLAYING METHOD AND DEVICE, MEDIUM AND BROWSER”, filed on Oct. 28, 2014, which claims priority to Chinese Patent Application No. 201310608510.2, titled “METHOD AND DEVICE FOR PLAYING MULTIMEDIA FILE IN WEBPAGE” and filed on Nov. 26, 2013 with the State Intellectual Property Office of People's Republic of China, both of which are incorporated herein by reference in their entireties.
TECHNICAL FIELD
The present disclosure relates to the technical field of web player, and in particular to a method and a device for playing a media file.
BACKGROUND
A web player is a player achieved by using a web technology (such as html, javascript, flash, css) and a play plug-in (such as a wmp music play plug-in, a flash music play plug-in, a QQ music play plug-in and a html5 audio play plug-in) of a browser in a window of a web browser.
In general, each time when a song is to be played by using the web player, the web player is opened by a browser window with a same name, so that the web player can be always opened in the same browser window of the browser, which ensures that there is only one web player playing the song.
In the conventional technology, it can be achieved that only one web browser is opened to play a song, but each time when a new song is to be played by using the opened web player, the web player window is reloaded, which cause refreshing a page of the web player window and reinitializing the page of the web player window, thereby causing a long time delay.
SUMMARY
A method for playing a media file is provided according to the present disclosure, so that a web player window can play a new media file without refreshing a page, when receiving a playing request from another web browser window.
A device for playing a media file is further provided according to the present disclosure, so that a web player window may play a new media file without refreshing a page, when receiving a playing request from another web browser window.
The method for playing a media file includes:
submitting media file information to a first window; and
determining whether the first window is a top-level window of a browser; creating a sub-window in the top-level window of the browser, setting the sub-window as the first window, loading a player logic in the top-level window of the browser, and playing the media file by using the player logic in the top-level window of the browser, in case that the first window is determined as the top-level window; and transferring the media file information to the top-level window of the browser to which the first window belongs, and playing the media file by using the player logic in the top-level window of the browser, in case that the first window is not determined as the top-level window.
In the above method, the process of submitting the media file information to the first window includes:
determining whether there is the first window; submitting directly the media file information to the first window, in case that there is the first window; and creating a first window and submitting the media file information to the first window, in case that there is no first window; where the first window is a browser window whose name is a preset name.
The process of creating a sub-window in the top-level window of the browser, and setting the sub-window as the first window of the browser includes:
modifying a name of the top-level window of the browser as a name different from the preset name, creating a hidden sub-window in the top-level window of the browser, and naming the hidden sub-window as the preset name.
In the method, the media file may be an audio file or a video file, etc.
A device for playing a media file includes:
a data transferring module, configured to submit a media file to a first window; and
a playing module, configured to determine whether the first window is a top-level window of a browser; create a sub-window in the top-level window of the browser, setting the sub-window as the first window, loading a player logic in the top-level window of the browser, and playing the media file by using the player logic in the top-level window of the browser, in case that the first window is determined as the top-level window; and transferring the media file information to the top-level window of the browser to which the first window belongs, and playing the media file by using the player logic in the top-level window of the browser, in case that the first window is not determined as the top-level window.
In the device, the process of submitting the media file information to the first window by the data transferring module includes:
determining whether there is the first window; submitting directly the media file information to the first window, in case that there is the first window; and creating a first window and submitting the media file information to the first window, in case that there is no first window; where the first window is a browser window whose name is a preset name.
In the device, the process of creating a sub-window in the top-level window of the browser, and setting the sub-window as the first window of the browser includes:
modifying a name of the top-level window of the browser as a name different from the preset name, creating a hidden sub-window in the top-level window of the browser, and naming the hidden sub-window as the preset name.
A media and a browser for achieving the method are further provided according to embodiments of the present disclosure.
The media file may be an audio file or a video file, etc.
With the method and the device for playing a media file, a window is created by a player page as a data transferring page such as a hidden iframe window; a media file is submitted to the data transferring page; and a dynamic scripting language of a top-level player page is directly invoked by a scripting language of the data transferring page to achieve playing the media file without refreshing a page for user perception. The method is achieved without resubmitting the media file to the player and refreshing the whole player, thereby avoiding refreshing the whole player when a new media file is loaded and played, and reducing the time delay. Since the data transferring page is a hidden iframe, when a playing page with a playlist submits data to the data transferring page, the data transferring page refreshes, but a user can not perceive that the data transferring page is refreshed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a flow chart of a method for playing a media file according to a first embodiment of the disclosure;
FIG. 2 is a flow chart of a method for playing a media file according to another embodiment of the disclosure;
FIG. 3 is a schematic structural diagram of a device for playing a media file according to the disclosure; and
FIG. 4 is a schematic diagram of a hardware structure of a device for playing a media file according to an embodiment of the disclosure.
DETAILED DESCRIPTION OF THE EMBODIMENTS
A method for playing a media file is provided according to the disclosure. FIG. 1 shows a flow chart of the method. The method includes steps S 101 to S 104 .
In step S 101 , media file information is submitted to a first window.
The media file information may be information such as a storage location of a media file.
In step S 102 , whether the first window is a top-level window of a browser is determined. Step 103 is proceeded, if he first window is the top-level window of the browser; and step S 104 is proceeded, if the first window is not the top-level window of the browser.
In step S 103 , a sub-window is created in the top-level window of the browser and is set as the first window of the browser, a player logic is loaded in the top-level window of the browser, and a media file is played by using the player logic in the top-level window of the browser.
The player logic refers to an interface of the player and a control method thereof.
In step S 104 , the media file information is transferred from the first window to the top-level window to which the first window belongs, and the media file is played by using the player logic in the top-level window of the browser.
The special implementation of S 101 may include:
determining whether there is the first window; submitting directly the media file information to the first window, if there is the first window; and creating a first window, and submitting the media file information to the first window, if there is no first window; wherein the first window is a browser window with a preset name.
In the step S 103 , the process of creating the sub-window in the top-level window of the browser, and setting the sub-window as the first window of the browser may include:
modifying a name of the top-level window of the browser as a name different from the preset name, creating a hidden sub-window in the top-level window of the browser, and naming the hidden sub-window as the preset name.
In the disclosure, a window is a frame realized in a computer system. The window may be visible or invisible to a user. The window may be an interface which exists independently, or an interface whose existence is not independent and has to depend on another window.
In the disclosure, the window may be associated with an application. For example, the browser window refers to a window associated with a browser application. For another example, the browser window may be a browser page, or a browser instance.
In the disclosure, the top-level window refers to an outermost window container which may exist independently. The top-level window may contain one or more derived sub-windows; and the sub-window is created in the top-level window or in a lower-level sub-window of the top-level window. For example, an iframe created in a top-level window is a sub-window of the top-level window. It may be understood for a person of ordinary skill in the art that the sub-window may have one or more derived sub-windows.
Windows with nested relationship may be created in an application window. An outer window is called as a parent window; and an inner window is called as a sub-window. A sub-window has to depend on a corresponding parent window and cannot exist independently.
In the disclosure, the top-level window of the browser to which a sub-window belongs refers to an outmost window container opened by a current browser. The sub-window is created in the top-level window or in a sub-window of the top-level window, and the existence of the sub-window depends on the top-level window.
In the disclosure, the hidden sub-window refers to a sub-window invisible to the user and created in a window.
In the method, the media file may be an audio file or a video file, etc.
Hereinafter specific embodiments are described in detail in conjunction with the drawings.
First Embodiment
In the embodiment, a media file is a song.
In the embodiment, a way, in which a window object of a web browser is named and a window of a web browser named as a preset name is used as a data transferring page to transfer song data, is mainly used. In the embodiment, the preset name of the data transferring page is playWindow 1 .
There are two kinds of windows of a web browser according to a hierarchical relationship. The first kind is a top-level window which is an outmost window opened by the browser; and the second kind is an iframe created in the top-level window of the browser. The page in a top-level window and the page in a sub-window may access each other and transfer data between each other through a dynamic scripting language such as javascript, in the case that the loaded pages belong to a same domain name.
FIG. 2 shows a flow chart of a method according to the embodiment. The method includes step S 201 to S 208 .
In step S 201 , a user clicks on a song to play the song in a browser window A with a song list including one or more songs.
In step S 202 , a dynamic scripting language of the window A such as javascript invokes an interface window.open (‘ ’, ‘playWindow 1 ’) of the browser with respect to opening a window, to open a data transferring page named as playWindow 1 .
In step S 203 , the browser determines whether there is the data transferring page playWindow 1 , namely a browser window named as playWindow 1 . Step 204 is proceeded, in case that there is no data transferring page playWindow 1 ; and step 205 is proceeded, in case that there is the data transferring page playWindow 1 .
In step S 204 , the browser creates the data transferring page named as playWindow 1 , and step S 205 is proceeded.
In step S 205 , the dynamic scripting language of the window A such as javascript submits the song data to the data transferring page named as playWindow 1 by using a POST mode. The reason for using the POST mode to submit the song data to the data transferring page is that a length of URL in the GET mode is limited in the browser and little information can be transfer in the GET mode while a length of the submitted data is not limited in the POST mode.
In step S 206 , the dynamic scripting language in the controlling module of the data transferring page named as playWindow 1 determines whether the data transferring page playWindow 1 is the top-level window of the browser. If the data transferring page playWindow 1 is the top-level window of the browser, it is indicated that the data transferring page is opened for the first time, a logic of a web player is not loaded, and the browser window needs to be redirected to a final page of the web player, and step s 207 is proceeded; and if the data transferring page playWindow 1 is not the top-level window of the browser, it is indicated that logic of the web player is loaded and the data transferring page playWindow 1 is a hidden iframe sub-window in the top-level window of the browser, and step s 208 is proceeded.
In step S 207 , the logic of the web player is loaded in the top-level window of the browser, and the name of the top-level window of the browser is changed from the name playWindow 1 originally belonging to the data transferring page to another name such as playWindow 2 . The hidden iframe sub-window is created in the top-level window of the browser named playWindow 2 , the hidden IFRAME sub-window is named as playWindow 1 , and the hidden IFRAME sub-window is a new data transferring page. The logic of the web player is loaded in the top-level window of the browser named playWindow 2 , data information of the song to be played is directly transferred to the logic of the web player, and the song corresponding to the song data is played by the logic of the web player. The method is ended.
In step S 208 , the data transferring page playWindow 1 invokes, by using the dynamic scripting language such as javascript, an interface of the player logic of the parent window of the data transferring page playWindow 1 , and transfers the song data to the top-level window such as playWindow 2 to which the data transferring page belongs. The song corresponding to the song data is played by using the player logic in playWindow 2 . The scripting language such as javascript in the data transferring page playWindow 1 directly invokes a playing interface of the player logic of the parent window playWindow 2 to play the song, thereby achieving the playing without refreshing the page of the web player for the user perception.
With the method, when receiving a playing request from other web browser, an independent and unique web player window may play a new song without reloading a web player page.
A device for playing a media file is further provided according to the disclosure. FIG. 3 shows a schematic structural diagram of the device. The device includes:
a data transferring module 301 , configured to submit a media file to a first window; and
a playing module 302 , configured to determine whether the first window is a top-level window of a browser; to create a sub-window in the top-level window of the browser, set the sub-window as the first window, load a player logic in the top-level window of the browser, and play the media file by using the player logic in the top-level window of the browser, in case that the first window is determined as the top-level window; and to transfer the media file information to the top-level window of the browser to which the first window belongs, and play the media file by using the player logic in the top-level window of the browser, in case that the first window is not determined as the top-level window.
In the above device, the process of submitting the media file information to the first window by the data transferring module 301 may include:
determining whether there is the first window; submitting directly the media file information to the first window, in case that there is the first window; and creating a first window; and submitting the media file information to the first window, in case that there is no first window, where the first window is a browser window whose name is a preset name.
The process of creating a sub-window in the top-level window of the browser, and setting the sub-window as the first window of the browser by the playing module 302 may include:
modifying a name of the top-level window of the browser as a name different from the preset name, creating a hidden sub-window in the top-level window of the browser, and naming the hidden sub-window as the preset name.
In the above device, the media file may be an audio file or a video file, etc.
FIG. 4 is a schematic diagram of a hardware structure of a device for playing a media file according to an embodiment of the disclosure. The media playing device may be a terminal device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a point of sales (POS) and an auto pc, etc, which is not limited in the disclosure.
The media playing device 1000 may include a communication unit 1110 , one or more memories 1120 of a computer readable storage media, an inputting unit 1130 , a displaying unit 1140 , a sensor 1150 , an audio circuit 1160 , a wireless fidelity (WiFi) module 1170 , one or more processors 1180 as a processing core and a power source 1190 , etc. It should be understood for those skilled in the art that the media playing device is not limited by the structure of the media playing device showed in FIG. 4 , and the media playing device may include more or less units than the structure shown in FIG. 4 , or include a combination of the units, or include different arrangements of the units.
The inputting unit 1130 is configured to receive input number information or character information, and to generate a key signal input associated with a user setting and a function control of the media playing device 1000 .
The displaying unit 1140 is configured to display information input by a user or information provided to the user. The displaying unit 1140 may include a display panel, which is configured by using a liquid crystal display (LCD), or an organic light-emitting diode (OLED), etc. Specially, in a case that the media file is a video file, the displaying unit 1140 may display an image of the video file.
The audio circuit 1160 may provide an audio interface. The audio circuit 1160 may transmit an electric signal converted from received audio data to a loudspeaker, and the loudspeaker converts the electric signal into a voice signal for outputting. Specially, the audio circuit 1160 may output audio data associated with the media file.
The media playing device 1000 further includes a memory and one or more programs stored in the memory, and instructions included in the one or more programs when executed by one or more processors, configure the media play device to:
submit media file information to a first window; and
determine whether the first window is a top-level window of a browser; create a sub-window in the top-level window of the browser, set the sub-window as the first window, load a player logic in the top-level window of the browser, and play the media file by using the player logic in the top-level window of the browser, in case that the first window is determined as the top-level window; and transfer the media file information to the top-level window of the browser to which the first window belongs, and play the media file by using the player logic in the top-level window of the browser, in case that the first window is not determined as the top-level window.
The number in the embodiments according to the disclosure is only used for description, and does not indicate advantages or disadvantages of the embodiments.
In view of above, a method and a device for playing a media file are provided according to the disclosure. By creating the hidden iframe window in the player page as the first window, the media file is submitted to the first window, and the dynamic scripting language of the top-level player page is invoked directly by the scripting language of the first window to play the media file, thereby achieving the playing of the media file without refreshing a page for user perception.
According to another embodiment of the disclosure, by executing a computer program including a program code which can play a media file when executed in a general computing device like a computer including processing units such as a central processing unit (CPU) a random access memory (RAM) and a read only memory (ROM), and a storage unit, a device and a browser for playing a media file are configured, and the media playing method according to embodiments of the disclosure are achieved.
The foregoing embodiments are only preferred embodiments of the disclosure and are not meant to limit the disclosure. All modifications, equivalent variations and improvements made without departing from the spirit and principle of the disclosure shall fall in the scope of the technical solutions of the disclosure. | A media file playing method and device. The method comprises: submitting information about a media file to a first window; judging whether the first window is a browser top window; if so, creating a sub-window in the browser top window, setting the sub-window as the first window, loading player logic in the browser top window, and playing the media file by using the player logic in the browser top window; otherwise, transmitting, by the first window, the information about the media file to the browser top window to which the first window belongs, and playing the media file by using the player logic in the browser top window. By means of the present invention, it can be achieved that a webpage player window can play a new media file without refreshing when playing requests of other webpage browser windows are received. | 6 |
FIELD OF THE INVENTION
The present invention relates to the field of air treatment devices, and particularly to devices for eradicating objectionable odors from toilet bowls and the like.
BACKGROUND OF THE INVENTION
Until the early 1800's, Europeans and Americans alike relieved themselves in chamber pots, outhouses and alleyways. Eventually, however, indoor plumbing became the standard. In America, the first city with modern waterworks was Philadelphia in 1820; the first city with a modem sewage system was Boston in 1823; and, the first toilet installed in the White House was in 1825 for John Quincy Adams.
A major contributor to the advancement of indoor toilet technology was an Englishman named Thomas Crapper. Through his plumbing fixture company, T. Crapper & Co, Chelsea, London, founded 1861, Mr. Crapper produced many improvements in the fixtures he manufactured. Crapper's name was stenciled on all the cisterns--and later, toilets--that he manufactured. It is likely because of his contributions that he is often accredited with the invention of the toilet. However, it was another Englishman named Alexander Cumming who in 1775 made perhaps the most significant improvement to the indoor toilet. While toilets to that day had emptied directly into a pipe which carried the waste to a cesspool, Cumming improved the device by adding a "stink trap" that kept water in the pipe, thus blocking the backflow of sewage gases. Absent the constant foul-smelling stench of sewer gases wafting through pipes and up into the house, the indoor toilet became an acceptable, and welcomed improvement.
While Cumming's invention addressed foul smelling gases downstream of the stink trap, treating objectionable odors developed in the toilet bowl itself has proven to be a formidable challenge. Many methods have been employed for treating and/or eliminating such odors, such as opening a window, lighting a match, spraying an aerosol deodorizer, and using a range of powered devices. The most common of such devices, the ceiling fan, is often difficult to install, requires ducting to the outside or attic, and has a flow rate that is generally too low to evacuate the odors as fast as most users would like.
One line of development for bathroom odor treatment devices encompasses devices mounted proximal to the toilet bowl and activated to draw the objectionable gases into a chamber, treat them and then exhaust them back to the bathroom area. A number of these and similar devices are disclosed in the following U.S. Patents:
______________________________________U.S. Pat. No. Inventor______________________________________5,727,262 Littlejohn5,555,572 Hunnicutt, Jr.5,519,897 DeSimone5,488,741 Hunnicutt, Jr.%,416,930 Waldner, et al.5,403,548 Aibe, et al.5,240,653 Ramkissoon5,161,262 Quaintance, Sr.4,876,748 Chun4,748,698 Kao4,472,841 Faulkner4,317,242 Stamper4,099,047 Kirkland, Jr.3,857,119 Hunnicutt, Jr.2,846,696 J.R. Herriott______________________________________
While devices disclosed in these patents exhibit a variety of beneficial features for treating and/or evacuating foul odors from a bathroom facility, they also suffer from a variety of drawbacks. For example, the devices disclosed in U.S. Pat. Nos. 4,876,748 and 5,727,262 are quite large and unsightly. Other of these patents describe devices that appear to draw the malodorous gases through some type of filter (U.S. Pat. Nos. 4,317,242, 5,488,741 and 5,555,572) or that draw the gases over a heating device before expelling them back into the air (U.S. Pat. Nos. 4,099,047 and 5,519,897). Further, many of such devices are fairly complex and therefore costly. It is believed that none of these devices achieves an acceptable balance among low consumer cost, ease of use, ease of maintenance, and most importantly, speed and effectiveness of use.
SUMMARY OF THE INVENTION
Generally speaking, there is provided an apparatus for treating and eradicating objectionable odors from toilet bowls and the like. The device is small, easy to use and maintain, and operates in a fast and efficient manner. Moreover, it may be used with a variety of commercially available products to treat and replace the objectionable odors with a wide range of pleasant aromas.
An apparatus for treating objectionable odors from a toilet bowl, where the toilet bowl includes a seat positioned above the toilet bowl, comprising a main body having an inlet opening, an outlet opening and a scent delivery chamber; means for mounting the main body proximal to the toilet bowl with the inlet opening positioned substantially between the bowl and the seat; a drawer removably securable to the main body; fan means for drawing gas in the inlet opening, through the scent delivery chamber and out the outlet opening; a power source; switch means wired with the fan means and the power means and engagable with the toilet seat to electrically connect the power source to the fan means upon downward pressure being applied to the toilet seat relative to the toilet bowl; scent delivery means positioned within the scent delivery chamber for releasing a scent at least when the fan means is drawing gas through the scent delivery chamber; and, wherein the drawer includes a closed condition securing the scent delivery means within the scent delivery chamber, and an open condition exposing and enabling removal of the scent delivery means.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an apparatus 10 for treating objectionable odors in toilet bowls and the like in accordance with the preferred embodiment of the present invention, apparatus 10 shown mounted to a standard toilet 11.
FIG. 2 is a front and side, perspective view of the apparatus 10 of FIG. 1.
FIG. 3 is a rear and side, perspective view of the apparatus 10 of FIG. 1.
FIG. 4 is a side view of the apparatus 10 of FIG. 1.
FIG. 5 is a top view of the apparatus 10 of FIG. 1.
FIG. 6 is a side view of the apparatus 10 of FIG. 1
FIG. 7 is a rear view of the apparatus 10 of FIG. 1.
FIG. 8 is a front view of the apparatus 10 of FIG. 1.
FIG. 9 is a bottom view of the apparatus 10 of FIG. 1.
FIG. 10 is a side, cross-sectional view of the apparatus 10 of FIG. 5 taken along the lines 10--10 and viewed in the direction of the arrows, and with drawer 16 in the removed condition.
FIG. 11 is a side, elevational view of a sponge tree 17 of FIG. 10 and of a sponge 97 partially applied to sponge tree 17.
FIG. 12 is a side, cross sectional view of drawer 16 of FIG. 10 and of sponge tree 17 and sponge 97 partially mounted to drawer 16.
FIG. 13 is a perspective view of drawer 16 of FIG. 10.
FIG. 14 is a perspective view of sponge tree 17 of FIG. 11.
FIG. 15 is a cross-sectional view of the sponge tree 17 and sponge 97 of FIG. 11 taken along the lines 15--15 and viewed in the direction of the arrows.
FIG. 16 is a top plan view of apparatus 10 of FIG. 1 and of mounting bracket 14.
DESCRIPTION OF THE PREFERRED EMBODIMENT
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, and any alterations or modifications in the illustrated device, and any further applications of the principles of the invention as illustrated therein are contemplated as would normally occur to one skilled in the art to which the invention relates.
Referring to FIG. 1, there is shown an apparatus 10 for treating and eradicating objectionable odors from toilet bowls and the like in accordance with the preferred embodiment of the present invention. Apparatus 10 is shown in use mounted to a standard toilet 11 by a mounting arm 14 to draw gases from within the toilet bowl 12, between the toilet bowl 12 and its seat 13, and to treat such gases, as described herein.
Referring to FIGS. 2-10, and with particular reference to FIG. 10, apparatus 10 is shown from a variety of angles and generally includes a main body 15, a drawer 16, a sponge tree 17 and a fan 18. Drawer 16 is configured to slide laterally from a closed condition (FIGS. 2-9) out and away from body 15 to an open or removed condition (FIG. 10). Body 15 is integrally molded into two mating body halves 19 and 20 that are mirror images of each other. Each half 19 includes structures 21 which defines holes that align with corresponding holes in the mating other half 20 when the two halves 19 and 20 are brought together. Pins 22 extend from within the holes of one half 19 and into the corresponding, aligned holes of the other half 20 to fix halves 19 and 20 in the desired mutual alignment to form main body 15, substantially as shown in FIGS. 2-9. Similarly, mutually aligned structures 23 in both halves 19 and 20 receive an appropriate securing member such as a nut and bolt combination 24 to fix the halves 19 and 20 together. Although the present embodiment describes main body 15 comprising two mirrored halves, the present invention contemplates manufacturing main body in a variety of different ways including, but not limited to, a unibody construction or two or more parts connected with each other in any appropriate manner, so long as the resulting structure includes the primary elements described herein. As halves 19 and 20 of the present embodiment are mirror images of each other, the following description may be made with reference to only body half 19, it being understood to apply equally to body half 20, unless otherwise stated.
Main body 15 includes an upper inlet spout 26, a battery shelf 27, a filter shelf 28, a drawer compartment shelf 29, opposing front and back fan support ledges 30 and 31, respectively, bottom wall 32, front wall 33, opposing side walls 34 and 35, and rear wall 36. Upper inlet spout 26 extends forwardly from front wall 33, and itself has top and bottom walls 39 and 40 that define a generally low profile inlet spout that diverges as it extends forwardly from front wall 33 to its wide and low-profile opening 42. Apparatus 10 is to be positioned at toilet bowl 12 with the widening, low profile spout structure positioned at or between the top 41 of bowl 12 and the corresponding toilet seat 13. The widened inlet opening 42 facilitates an unrestricted draw of gases from bowl 12.
An electrical switch 44 is mounted by appropriate means such as screws (not shown) to body 15. A spring metal activation arm 45 extends from switch 44, through spout 26, out opening 42, and forwardly of spout 26. With apparatus 10 in its inactivated and rest condition (as shown in FIG. 10), a hump 46 defined at the forward end of activation arm 45 extends a predetermined amount above top wall 39, as shown. As discussed herein, when weight is applied to seat 13, seat 13 will move downwardly slightly, toward toilet bowl 12, just enough to depress activation arm 45 at hump 46, which action will pivot arm 45 at switch 44 to activate switch 44. Battery shelf 27 is sized to receive a battery 48 thereon. Extending rearwardly of battery shelf 27 and at the lateral center thereof is a shaped, vertically extending flange 50 which defines a hole 51 therein.
Filter shelf 28 is juxtaposed a sufficient distance below battery shelf 27, flange 50 and switch 44 to receive a filter 54 thereon. Filter 54 has a wafer shape and is made of any appropriate material that removes odiferous particulates from a gas that flows through such material. In one embodiment, filter 54 is made of a charcoal-based, fibrous material. Filter 54 may be positioned, and thus changed from time to time, simply by sliding it in and onto shelf 28 from the rear of main body 15 when drawer 16 is removed from main body 15 (FIG. 10). Filter shelf 28 is not a solid sheet, but rather defines one or more openings 55 therein to minimize any restriction to fluid flow therethrough. The number and size of such openings 55 may vary as desired, but it is desired to minimize obstruction to fluid flow from one side of filter shelf 28 to the other, and it is therefore desired to maximize the total lateral area of openings 55 while simultaneously providing a stable platform for supporting filter 54. Likewise, drawer compartment shelf 29 defines one or more openings 56 therein to permit unrestricted fluid flow from one side of shelf 29 to the other, and its is similarly desired to minimize obstruction to such fluid flow, and therefore desired to maximize the total lateral area of openings 56. Drawer compartment shelf 29 contributes to the support of drawer 16 and, together with filter shelf 28, front wall 33, side walls 34 and 35, and drawer 16, defines sponge chamber 59.
Extending inwardly from front and rear walls 33 and 36 are fan support ledges 30 and 31, respectively. A fan 18 is supported upon ledges 30 and 31 within fan chamber 62, fan chamber 62 being defined by drawer compartment shelf 29, bottom wall 32, and front, side and rear walls 33-36. A series of vent slots 61 are defined in bottom wall 32 and extend slightly upward along side walls 34 and 35. Fan 18 is any appropriate fan unit which preferably provides a high fluid flow rate is efficiently powered by battery 48, and is relatively quiet. Fan 18 has an upwardly disposed flow inlet to communicate with the openings 56 in drawer compartment shelf 29 and has a downwardly disposed flow exhaust to communicate with vent slots 61. In the present embodiment, fan 18 is positioned upon ledges 30 and 31 of one body half 19 and is secured within fan chamber 62 upon securing body halves 19 and 20 together. In the assembled condition, with body halves 19 and 20 secured together, battery shelf 27, filter shelf 28, drawer compartment shelf 29 and ledges 30 and 31 extend all the way across main body 15, side wall 34 to side wall 35. An arcuate projection 64 juts inwardly from side wall 34 a similar projection (not shown) juts inwardly from mating side wall 35. Projection 64 is sized to register with a complementary shaped recess in drawer 16.
A thumb switch 65 slides within a slot 66 defined in spout 26 between a forward "on" position (shown in phantom at 69) and a rearward "off" position 70. A downwardly projecting lug 71, extending downwardly from switch 65, moves in and out of engagement with activation arm 45 when thumb switch 65 is moved between the on and off positions. That is, when switch 65 is slid forward to the on position 69, projection 71 engages and pushes arm 45 downwardly at a point close to the connection of arm 45 to switch 44. Further pivoting of arm 45, as by weight being applied to seat 13, will apply sufficient additional torque to arm 45 to close switch 44. Conversely, sliding switch 65 to the off position releases the downward bias to arm 45 at switch 44 which disengages switch 44. That is, because activation arm 45 is made of spring metal or a similar material which allows it to bend somewhat over its length, pivoting of activation arm 45 by applying downward pressure to hump 46 will not transmit sufficient torque through arm 45 to switch 44 to close switch 44 and turn on fan 18 when thumb switch 65 is in the off position. The present invention contemplates the use of any appropriate switch arrangement where a switch may be closed by the slight movement of a member like activation arm 45, but where closure of the switch may be overridden by another switch such as thumb switch 65. Wires 65 extend among switch 44, battery 48 and fan 18 to complete the circuit and power fan 18 when switch 44 is closed.
An alternative embodiment is contemplated wherein thumb switch 65 acts to turn on fan 18 even where there is no input from activation arm 45. That is, when switch 65 is in the "off" position, activation arm 45 may operate as described to engage switch 44 and activate fan 18. However, where a child or very lightweight person is too light, perhaps, to activate arm 45, in view of the composition of seat 13 when sitting on seat 13, thumb switch 65 may be slid to the "on" position to activate switch 44 and turn on fan 18. Another embodiment is contemplated wherein thumb switch 65 may be connected with switch 44 and/or arm 45 to move from an "off" position, completely disabling fan 18, an "on" position, turning on fan 18 and overriding activation arm 45, and an intermediate or "seat" position whereby activation arm 45 is operable through switch 44, to activate fan 18 between on and off positions.
Referring now to FIGS. 2-15, and particularly to FIGS. 2, 3 and 10-15, drawer 16 includes rear wall 75, opposing side walls 76 and 77 and sponge shelf 78. The forwardly facing edge 80 of drawer 16 has a contour that is complementary with the rearwardly facing edge 81 of main body 15, and the lower edge 82 of rear wall 75 has a contour that is complementary with upper edge 83 of rear wall 36 of main body 15. Drawer 16 may therefore be slidingly received by main body 15 from the open or removed condition (FIG. 10) to the closed condition (FIGS. 2-9), whereby edges 80 and 81 and edges 82 and 83 come into complete abutting alignment and sponge shelf 78 slides along and atop drawer compartment shelf 29.
Sponge tree 17 has the configuration as generally shown in FIG. 14 with an upper retaining wall 86 and a central post 87 depending downwardly from the center thereof. Retaining wall 86 comprises a central spine 88 and a series of spaced apart legs 89 extending outwardly therefrom. Spine 88 and legs 89 together define both an upper retaining wall for a sponge and a compression platform that may be used to assist in rinsing out such sponge, as will be described herein. Spine 88 and legs 89 have a generally circular cross section in plan view which is approximately equal to or slightly smaller than the dimensions of filter shelf 28 so that retaining wall 86 will fit within sponge chamber 59 just below filter shelf 28. Spine 88 and outwardly extending legs 89 define a series of gaps 90 therebetween which permits fluid flow therethrough. As with filter shelf 28 and drawer compartment shelf 29, spine 88 and legs 89 are configured to maximize the fluid flow rate through gaps 90 while still providing sufficient strength to withstand a downwardly applied compression force for assembling apparatus 10 and changing or cleaning the corresponding sponge.
Central post 87 has a generally flat, rectangular configuration in cross-section with arcuate longitudinal humps 91 and 92 extending outwardly from opposing sides of post 87 and all along the length of post 87, from upper retaining wall 86 and down to the base 93 of post 87, except for a small gap 95 where humps 91 and 92 are absent. That is the absence of a section of each hump 91 and 92 on opposing sides of post 87 defines one gap of 95 at the lower section of each hump 91 and 92. The gaps 95 are located the same distance up from base 93. Base 93 has a generally circular cross section with a diameter that is approximately equal to the width of central post 87. Arcuate, longitudinal humps 91 and 92 are together generally circular in cross-section. They may have other cross-sectional shapes, whereby the shape of the corresponding combined enlarged opening (at 109 and 110 in slot 106 as described herein) will be complementary.
A sponge 97 (FIGS. 11, 12 and 15) has a generally circular cross section in plan view with a diameter that is approximately equal to the diametrical dimensions of upper retaining wall 86. Sponge 97 has a height which is approximately equal to or slightly less than the height of central post 87. Sponge 97 defines a central hole 98, the diameter of which is preferably slightly less than the width of central post 87. Sponges are available in a wide variety of configurations, construction and degrees of porosity. Typically, the more porous the sponge, the lower its capacity to retain fluids. Although because of its inherent porosity, sponges will typically permit fluid flow, and specifically gas flow therethrough, sponge 97 is provided with a plurality of additional recesses 99 and holes 100 along its height to enhance fluid flow from its top surface 101 to its bottom surface 102. These recesses 99 and holes 100 may be defined in sponge 97 in a variety of ways including, but not limited to mechanical and chemical means. Likewise, sponge 97 may be selected from a class of sponges that inherently have a high number of both large and small openings which will facilitate a high rate of fluid flow and a sufficiently high degree of material surface area. A high degree of surface area is desirable to enable sponge 97 to be impregnated with substances having particular aromas.
Referring to FIGS. 12 and 13, sponge shelf 78 includes a raised central, and laterally extending platform. Platform 105 defines a slot 106 which originates somewhat rearwardly of the center of sponge shelf 78 and extends therefrom along a longitudinal axis 107 to the forward edge 108 of shelf 78. At the center of sponge shelf 78, slot 106 has a shape that is substantially identical to the cross sectional shape of central post 87 as is viewed in FIG. 15. That is, slot 106, at the center of shelf 78, bulges outwardly, in opposing directions, at 109 and 110, to define a central, enlarged opening 104. From enlarged opening 104, slot 106 extends a short distance rearwardly at and diverges as it extends toward forward edge 108. Also, platform 105 is raised slightly above the level of the rest of sponge shelf 78, thereby creating a generally rectangular shaped, lateral slot at 112 the width 113 of such slot 112 is approximately equal to or slightly greater thanthe diameter of base 93 of sponge tree 17. As with filter shelf 28, drawer compartment 29 and upper retaining wall 86, sponge shelf 78 is provided with openings 114 to permit fluid flow therethrough, the total area defined by such openings being maximized to minimizing any restriction to such fluid flow.
Sponge shelf 78 further defines a pair of inwardly extending recesses 115 on opposing sides thereof and slightly rearwardly of forward edge 108. Recesses 115 are sized and positioned to register with the mating projections 64 in main body 15. Thus, when drawer 16 is moved into its closed condition (FIGS. 2-9), sponge shelf 78 snaps into registry with projections 64 at recesses 115. Such registration between recesses 115 and projections 64 firmly holds drawer 16 in the closed position relative to main body 15.
If desired, drawer 16 may be more firmly secured to main body 16, and even locked thereto to prevent unauthorized opening of drawer 16. This is accomplished by registration between flange 50 and a complementary shaped and positioned slot 116 (FIG. 13) defined in the upper portion of rear wall 75 of drawer 16. Further, drawer 16 defines a pair of curved and generally laterally extending recesses 118 and 119 and defines a bridge 120 that follows the overall contour of rear wall 75, separates recesses 118 and 119 and is in substantial planar alignment with slot 116. When drawer 16 is moved to its closed condition, flange 50 extends through slot 116, between recesses 118 and 119 and up against the forwardly facing, underside of bridge 120. Hole 51 is exposed by virtue of recesses 118 and 119, and an appropriate locking member such as a padlock may be positioned through hole 51 and around bridge 120, thus preventing the removal of drawer 16 from main body 15.
Indentations 123 are provided on opposing sides of drawer 16 to facilitate the movement of drawer 16 relative to main body 15.
In use, sponge 97, is provided either pre-scented at purchase or may be conditioned by applying a desired scent with a commercial product such as an aerosol or pump-spray, auto or room air freshener. Sponge 97 is then applied to sponge tree 17 (FIG. 11) by inserting central post 87 through central hole 98 until the top surface 101 of the sponge 97 rests against the underside of upper retaining wall 86. Sponge 97 is then manually compressed (shown at 123 in FIG. 12) up against upper retaining wall 86, as shown in FIG. 12, so that gaps 95 in humps 91 and 92 are exposed. Sponge and sponge tree combination 97/17 is then mounted to drawer 16 by sliding central post 87 through slot 106 whereby the opposing edges 121 of slot 106 are aligned within gaps 95. When sponge and sponge tree combination 97/17 reaches the center of sponge shelf 78, and arcuate humps 91 and 92 are vertically aligned with enlarged opening 104, sponge 97 may be released from its compressed position 123, which action causes the bottom surface 102 of sponge 97 to press against sponge shelf 78. Because humps 91 and 92 are aligned with complementary shaped, enlarged opening 104, sponge tree 17 may rise relative to platform 105 until base 93 engages the underside of platform 105 and within lateral slot 112. In this configuration, the lowermost portions of are nested within complementary shaped enlarged opening 104, and sponge tree 17 may be slid vertically through opening 104 and relative to platform 105. However, because the combined lateral dimension of humps 91 and 92 is greater than the width of slot 106 adjacent to enlarged opening, sponge tree 17 is constrained from moving laterally. To remove sponge tree 17, it must be moved vertically until gaps 95 align with the edges 121 of slot 106, and then sponge tree 17 may be slid forwardly out of slot 106. With this configuration, sponge tree 17 and sponge 97 are firmly mounted within drawer 16. With an appropriate filter 54 positioned atop filter shelf 28, the drawer can now be joined with main body 15, as described herein, until edges 80 and 81 and edges 92 and 93 mate, and whereby sponge 97 will be securely positioned within sponge chamber 59, below filter shelf 28 and above drawer compartment shelf 29. Apparatus 10 is now ready for operation. Upon activation of fan 18, gases are drawn in through opening 42, through filter 54, through scented sponge 79, through fan 18, and out through vent slots 61, the ejected gases now devoid of some or much of the original objectionable odors and having a desired aroma picked up from the treated sponge 97.
The sponge tree and sponge combination 17/97 also cooperates with drawer 16 to facilitate rinsing or cleaning of the sponge and related components. Upon removal of drawer 16, and without removing sponge tree 17 from drawer 16, the drawer, sponge tree, and sponge combination 16/17/97 may be positioned appropriately under a stream of water or in a container with cleaning solution or water and appropriately cleaned or rinsed. Upon removal from such water or cleaning solution, the user may compress upper retaining wall 86 toward sponge shelf 78, whereby post 87 slides through complementary shaped slot 106 and enlarged opening 104, and sponge 97 is compressed therebetween, which action squeezes the majority of fluid from sponge 97. This procedure may be repeated as many times as necessary to clean and/or rinse sponge 97. This configuration thereby generally permits the user to clean and/or rinse sponge 97 without requiring sponge 97 to be removed from sponge tree 17 and drawer 16, and further minimizing the amount of direct contact between the users hands and sponge 97. This procedure further permits the sponge to be cleaned and/or rinsed and then for a different fragrance to be applied to sponge 97. If desired, sponge 97 may be replaced with a new sponge simply by reversing the steps for installing the sponge.
Referring not to FIGS. 1 and 16, there is shown a support arm 14 suitable for mounting apparatus 10 to a standard toilet bowl 12. Apparatus 14 includes at one end an inboard mounting section 130 and extends through a pair of bends to an outboard mounting section 131 at the opposite end. Inboard mounting section 130 is provided with an elongate slot 133 that is sized to receive a standard toilet seat mounting bolt 134. An L-shaped bracket 135 depends down from the bottom of upper inlet spout 26 (FIGS. 8-10) and over to front wall 33 to create, in conjunction with the underside of spout 26, an opening 137 sized to receive outboard mounting section 131 of support arm 14 therethrough. Support arm 14 is connected to toilet bowl 12 simply by removing one of the toilet seat mounting bolts 134 (and its corresponding wing nut or similar structure (not shown)) from its connection to toilet bowl 12, positioning support arm 14 atop toilet bowl 12, between toilet seat 13 and tank 136 substantially as shown in FIG. 1, and with slot 133 in alignment over the toilet seat mounting hole (not shown) of toilet bowl 12, and then extending toilet seat mounting bolt 134 through slot 133 and back through the toilet seat mounting hole. Bolt 134 is secured thereto with the corresponding wing nut (not shown). Apparatus 10 is then moved into position whereby outboard mounting section 131 extends through the opening 137 of L-shaped bracket 135. A set screw 140 extends up through bracket 135 to tighten against outboard mounting section 131, thereby firmly securing apparatus 10 to support arm 14.
Because toilets come in a variety of sizes and shapes, the slot 133 in support arm 14 allows support arm 14 to be adjusted to a variety of positions, and apparatus 10 may be slid along outboard mounting section 131, until apparatus 10 is in the desired position relative to bowl 12. Such desired position is substantially shown in FIG. 10 where inlet opening 42 is just above and to the outside of the top surface 41 of bowl 12. Because support arm 14 has a thickness and will raise one side of toilet seat 13 relative to bowl 12 when apparatus 10 is applied thereto, a washer (not shown) made of the same material as support arm 14 and having the same relative thickness as support arm 14 is contemplated for insertion between toilet bowl 12 and the other toilet seat mounting bolt (not shown) to raise that side to level. While standard toilet seats generally have cushion members (not shown) that are mounted to the underside of seat 13 to cushion the contact between seat 13 and bowl 12 when seat 13 is lowered, application of apparatus 10 to bowl 12 will still raise the rear of seat 13 from an otherwise level conditioned, and seat 13 will tilt forward. The present invention contemplates inclusion of replacement cushion members (not shown) to replace the standard cushion members, the replacement cushion members having a thickness that is sufficiently greater than the original cushion members to level out seat 13.
Support arm 14 and its companion washer, along with main body 15, drawer 16, sponge tree 17 and other components herein are made of any appropriate material such as plastic which can be easily cleaned by the user.
Alternative embodiments are contemplated wherein sponge 97 comprises other materials in other configurations, such other materials and configurations being capable of holding a scented material, or comprising a scented material, which can be released into a surrounding gaseous atmosphere. For example, such other materials and configurations include, but are not limited to, the wide variety of solid air fresheners currently available or to be available in the future. Thus, while the present embodiment describes the scent delivering apparatus as a sponge 97, such scent delivering apparatus is intending to include any material that releases a desired scent into the fan-induced air flow. Where sponge 97 is to be replaced by a solid air freshener, sponge tree 17 is removed from drawer 16 and the solid air freshener is placed directly atop sponge shelf 78. Alternative embodiments are contemplated wherein a solid air freshener is provided with a central tree similar to sponge tree 17 with an appropriate lower shape and configuration that mates with a complementary configuration in sponge shelf 78 to facilitate the insertion of such solid air freshener into drawer 16 without the user having to physically touch the air freshener material.
The present invention contemplates alternative means for mounting apparatus 10 proximal to toilet bowl 12. Support arm 14 is believed to be preferable since it is simple, cost-efficient, easy to use, and incorporates the structure of the standard toilet bowl. However, alternative structures are contemplated so long as inlet opening 42 is positioned as close to the gap between bowl 12 and seat 13 as possible to maximize the draw of gases from within bowl 12. That is, apparatus 10 will naturally draw gases from both inside bowl 12 and from the atmosphere outside of bowl 12 (unless the gap between bowl 12 and seat 13 is completely sealed off except for apparatus 10). The farther that apparatus 10 is positioned from bowl 12 and seat 13, the lower the percentage of toilet bowl gases that will be drawn through apparatus 10 and the less effective apparatus 10 will be. Support arm 14 permits a varied adjustment of the position of apparatus 10 relative to the bowl/seat gap, thereby enabling maximum effectiveness of apparatus 10.
Alternative embodiments are also contemplated wherein apparatus 10, having a generally flat bottom wall 32, may be used at locations other than the bathroom toilet merely by sitting apparatus 10 upon an appropriate surface.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrated and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. | An apparatus for treating objectionable odors from a toilet bowl, where the toilet bowl includes a seat positioned above the toilet bowl, comprises a main body having an inlet opening, an outlet opening and a scent delivery chamber; an apparatus for mounting the main body proximal to the toilet bowl with the inlet opening positioned substantially between the bowl and the seat; a drawer removabley securable to the main body; a fan for drawing gas in the inlet opening, through the scent delivery chamber and out the outlet opening; a power source; a switch for electrically connecting the power source to the fan; a scent delivery device positioned within the scent delivery chamber for releasing a scent at least when the fan is drawing gas through the scent delivery chamber; a tree sized and shaped to hold the scent delivery device within the scent delivery chamber; and, wherein the drawer includes a closed condition securing the scent delivery device within the scent delivery chamber, and an open condition exposing and enabling removal of the scent delivery device. | 4 |
RELATED APPLICATIONS
This application is a continuation-in-part of application Ser. No. 08/146,382 filed on Oct. 29, 1993, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a processor architecture, and more particularly to a processor architecture combining floating point functional units and non-floating point functional units.
2. Description of the Related Art
Processors generally process a single instruction of an instruction set in several steps. Early technology processors performed these steps serially. Advances in technology have led to pipelined-architecture processors, which may be called scalar processors, which perform different steps of many instructions concurrently. A "superscalar" processor is also implemented using a pipelined structure, but further improves performance by supporting concurrent execution of scalar instructions.
In a superscalar processor, instruction conflicts and dependency conditions arise in which an issued instruction cannot be executed because necessary data or resources are not available. For example, an issued instruction cannot execute when its input operands are dependent upon data calculated by other instructions that have not yet completed execution.
Superscalar processor performance is improved by the speculative execution of branching instructions and by continuing to decode instructions regardless of the ability to execute instructions immediately. Decoupling of instruction decoding and instruction execution requires a buffer between the processor's instruction decoder and the circuits, called functional units, which execute instructions.
Floating point functionality has been available in nonsuperscalar computers and processors for many years. Microprocessors typically perform floating point and integer instructions by activating separate floating point and integer circuits. A standard for floating point arithmetic has been published by Institute of Electrical and Electronic Engineers in "IEEE Standard For Binary Floating-Point Arithmetic", ANSI/IEEE Standard 754-1985, IEEE Inc., 1985. This standard is widely accepted and it is advantageous for a processor to support its optional extended floating point format.
Some computers employ separate main processor and coprocessor chips. The main processor reads and writes to a floating point register stack to effect floating point operations. For example, an 80386 main processor, which is a scalar microprocessor and an 80387 math coprocessor are available from various manufacturers. The math coprocessor controls floating point operations initiated upon a request from a main processor. The main processor accesses a register stack, which includes eight registers for holding up to eight floating point values that are stored in double extended format. A 32-bit single precision or 64-bit double precision value is loaded from memory and expanded to 80-bit double extended format. Conversely, the double extended value is shortened and rounded to a single or double precision value as it is stored in memory.
A Pentium™ microprocessor, available from Intel Corporation of Santa Clara, Calif., is a superscalar processor which executes mixed floating point and integer instructions by controlling the operation of two instruction pipelines. One of the pipelines executes all integer and floating point instructions. The second pipeline executes simple integer instructions and a floating point exchange instruction.
It is desirable to incorporate a floating point functional unit with several integer functional units in a superscalar processor. W. M. Johnson in Superscalar Processor Design, Englewood Cliffs, N.J., Prentice Hall, 1991, p. 45, provides two sets of processor functional blocks, an integer set structured on 32-bit units and busses and a floating point set organized into 80-bit structures. In a superscalar processor, the floating point and integer sets each require separate register files, reorder buffers and operand and result busses. Floating point instructions are dispatched by an instruction decoder within the floating point set. A separate instruction decoder is provided in the integer set of units. The Johnson approach supports floating point arithmetic in a processor which incorporates a superscalar architecture, decoupling of instruction decoding and instruction execution, and branch prediction. The considerable performance advantages of this approach are achieved at the expense of duplicating resources. Moreover, some reduction in performance arises from coordination of operations between the integer and floating point sets of functional blocks.
SUMMARY OF THE INVENTION
The present invention is a processor and architecture having an internal machine organization for improved handling of integer and floating point data which better realizes the advantages of a superscalar architecture, decoupling of instruction decoding and instruction execution, and branch prediction.
The superscalar processor and architecture of the present invention support integer and IEEE extended floating point format standard arithmetic while advantageously avoiding duplication of functional blocks such as decoders, register files, reorder buffers and associated operand and result busses. Preventing resource duplication reduces production and operating costs, circumvents complexity arising from interactions between duplicated resources and facilitates control of timing relationships between operations performed by the different sets of functional blocks.
The architecture of the present invention advantageously incorporates handling of integer and floating point data in a pipelined or superscalar processor in which either integer data or floating point data flows in any data path of a set of multiple data paths under common control in a common general manner.
It is a particular advantage of the superscalar processor of the present invention to manage unresolved data dependencies using a single reorder buffer memory for storing dependency and tagging information for both integer and floating point operations. One function of a reorder buffer is to maintain the order of dispatched operations, including the order of interspersed integer and floating point operations. A single reorder buffer maintains the operation order in a simple manner. In contrast, a processor having separate integer and floating point reorder buffers requires extensive cross-referencing to maintain the operation order.
In addition, the performance of the superscalar processor of the present invention is advantageously enhanced by implementing a single reorder buffer to manage speculative execution of intermixed integer and floating point operations using branch prediction and recovery. A single reorder buffer maintains the order of integer, floating point and branch operations. The position of a branch instruction with respect to other entries in the reorder buffer is rendered by a pointer. Thus, the instruction sequence is reflected in a single sequence of reorder buffer entries, with a single branch pointer. Flushing the speculative state after a mispredicted branch may be easily achieved by changing as little as a single memory during recovery after a mispredicted branch, without regard for the type of data stored and without the need for complex control structures or serialization of instructions.
The processor and architecture of the present invention achieve these advantages by supplying a new processor core for concurrently executing mixed integer and floating point operations, including a first functional unit utilizing operand data of a first size and a second functional unit utilizing operand data of a second size. Several operand busses connect to the functional units to furnish data. The width of the operand busses is sufficient to communicate either first or second size data.
Another embodiment of the invention is a method for communicating operand data in a processor for implementing a mixed instruction set. This instruction set defines operations executing on a first type (e.g. integer) of functional unit utilizing operand data of a first size (e.g. 32 bits) and operations executing on a second type (e.g. floating point) of functional unit utilizing operand data of a second size (e.g. 80 or more bits) greater than the first size. The method includes the step of apportioning a second type of operation of into a plurality of suboperations, each of which is associated with suboperand data of a size proportionately smaller than the second size (e.g. 40 or more bits). The method also includes the step of dispatching the plurality of suboperations and associated suboperand data to the functional unit of the second type with the suboperand data being communicated on busses of a third size (e.g. 40 or more bits) that accommodates either the first size or the apportioned second size. Additional steps of the method include recombining the dispatched suboperand data into operand data of the second size and executing the apportioned operation to generate a result of the second size.
An additional embodiment of the invention is a processor for executing, in parallel, several operations utilizing either integer or floating point operand data. The processor includes a decoder for decoding and dispatching several operations. The decoder includes circuits for partitioning each floating point operation into multiple associated suboperations, each of which is associated with a floating point suboperand, which are dispatched in parallel. The processor also includes a floating point functional unit, which is coupled to the decoder to receive control signals including the dispatched suboperations. The functional unit includes circuits for recombining the suboperand data, executing the floating point suboperations in a single operation which utilizes the recombined data and circuits for partitioning the execution result into multiple subresults.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is better understood and its advantages, objects and features made better apparent by making reference to the following description, taken in conjunction with the accompanying drawings, in which like reference numbers identify like elements, wherein:
FIG. 1 is a architecture-level block diagram of a processor for implementing a mixed integer/floating point core;
FIG. 2 is a pictorial representation illustrating the format of, respectively, an extended precision number and an extended precision number segmented into half-operands;
FIG. 3 is an architecture-level block diagram of a register file within the processor of FIG. 1;
FIG. 4 is a pictorial representation illustrating a memory format in the register file shown in FIG. 3;
FIG. 5 is an architecture-level block diagram of a reorder buffer within the processor of FIG. 1;
FIG. 6 is a pictorial representation illustrating a memory format within the reorder buffer of FIG. 5;
FIG. 7 is a pictorial representation which depicts multiple bit fields within a reorder buffer array element of a plurality of such elements within the reorder buffer of FIG. 5;
FIGS. 8, 9, 10, 11 and 12 are pictorial depictions which illustrate formats of the result bit field of the reorder buffer array element of FIG. 7, including formats for, respectively, a half-operand extended precision floating point number, a doubleword integer, a word integer, a byte integer and an address for a branch instruction;
FIG. 13 is a schematic diagram of a layout of a mixed floating point/integer processor core;
FIG. 14 is a schematic block diagram illustrating data flow and dimensions of data paths within the processor of FIG. 1;
FIGS. 15 and 16 are pictorial illustrations depicting formats of, respectively, an extended precision number, an extended precision number decomposed into half-operands and bit fields within the lower order half-operand, all of which are operated upon by functional units of the FIG. 1 processor; and
FIG. 17 is an architecture-level block diagram of a load/store functional unit of the FIG. 1 processor.
FIG. 18 is a table which illustrates segmentation of floating point operations and operands into a pair of suboperations and associated suboperands.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The architecture and functional blocks of a superscalar processor 10 having an instruction set for executing integer and floating point operations are shown in FIG. 1. A 64-bit internal address and data bus 11 communicates address, data, and control transfers among various functional blocks of the processor 10 and an external memory 14. An instruction cache 16 parses and pre-decodes CISC instructions. A byte queue 35 transfers the predecoded instructions to an instruction decoder 18, which maps the CISC instructions to respective sequences of instructions for RISC-like operations ("ROPs"). The instruction decoder 18 generates type, opcode, and pointer values for all ROPs based on the pre-decoded CISC instructions in the byte queue 35. It is to be understood that, while the illustrative embodiment shows a processor 10 for receiving stored complex instructions and converting the complex (CISC) instructions to RISC-type ROPs for execution, processors that operate either exclusively on CISC instructions or RISC-type operations, as well as to processors that change the form of the instruction upon decoding, are also envisioned.
A suitable instruction cache 16 is described in further detail in U.S. patent application Ser. No. 08/145,905 filed on Oct. 29, 1993 (David B. Witt and Michael D. Goddard, "Pre-Decode Instruction Cache and Method Therefor Particularly Suitable for Variable Byte-Length Instructions", Attorney Docket Number M-2278). A suitable byte queue 35 is described in additional detail in U.S. patent application Ser. No. 08/145,902 filed on Oct. 29, 1993, now abandoned (David B. Witt "Speculative Instruction Queue and Method Therefor Particularly Suitable for Variable Byte-Length Instructions", Attorney Docket Number M-2279). A suitable instruction decoder 18 is described in further detail in U.S. patent application Ser. No. 08/146,383 filed on Oct. 29, 1993 (David B. Witt and Michael D. Goddard "Superscalar Instruction Decoder", Attorney Docket Number M-2280). Each of the identified patent applications is incorporated herein by reference in its entirety.
The instruction decoder 18 dispatches ROP operations to functional blocks within the processor 10 over various busses. The processor 10 supports four ROP issue, five ROP results, and the results of up to sixteen speculatively executed ROPs. Up to four sets of pointers to the A and B source operands and to a destination register are furnished over respective A-operand pointers 36, B-operand pointers 37 and destination register pointers 43 by the instruction decoder 18 to a register file 24 and to a reorder buffer 26. The register file 24 and reorder buffer 26 in turn furnish the appropriate "predicted executed" versions of the RISC operands A and B to various functional units on four pairs of 41-bit A-operand busses 30 and 41-bit B-operand busses 31. Associated with the A and B-operand busses 30 and 31 are operand tag busses, including four pairs of A-operand tag busses 48 and B-operand tag busses 49. When a result is unavailable for placement on an operand bus, a tag that identifies an entry in the reorder buffer 26 for receiving the result when it becomes available is loaded onto a corresponding operand tag bus. The four pairs of operand and operand tag busses correspond to four ROP dispatch positions. The instruction decoder, in cooperation with the reorder buffer 26, specifies four destination tag busses 40 for identifying an entry in the reorder buffer 26 that will receive results from the functional units after an ROP is executed. Functional units execute an ROP, copy the destination tag onto one of five result tag busses 39, and place a result on a corresponding one of five result busses 32 when the result is available. A functional unit directly accesses a result on result busses 32 when a corresponding tag on result tag busses 39 matches the operand tag of an ROP awaiting the result.
The instruction decoder 18 dispatches opcode information, including an opcode on an opcode type, that accompanies the A and B source operand information via four opcode/type busses 50.
Processor 10 includes several functional units, such as a branch unit 20, an integer functional unit 21, a floating point functional unit 22 and a load/store functional unit 80. Integer functional unit 21 is presented in a generic sense and represents units of various types such as arithmetic logic units, a shift unit, and a special register unit. Branch unit 20 validates the branch prediction operation, a technique which allows an adequate instruction-fetch rate in the presence of branches and is needed to achieve performance with multiple instruction issue. A suitable branch prediction system, including a branch unit 20 and instruction decoder 18, is described in further detail in U.S. Pat. No. 5,136,697 (William M. Johnson "System for Reducing Delay for Execution Subsequent to Correctly Predicted Branch Instruction Using Fetch Information Stored with each Block of Instructions in Cache"), which is incorporated herein by reference in its entirety.
Processor 10 is shown having a simple set of functional units to avoid undue complexity. It will be appreciated that the number and type of functional units are depicted herein in a specified manner, with a single floating point functional unit 22 and multiple functional units 20, 21 and 22 which generally perform operations on integer data, but other combinations of integer and floating point units may be implemented, as desired. Each functional unit 20, 21, 22 and 80 has respective reservation stations (not shown) having inputs connected to the operand busses 30 and 31 and the opcode/type busses 50. Reservation stations allow dispatch of speculative ROPs to the functional units.
Register file 24 is a physical storage memory including mapped CISC registers for integer and floating point instructions. It also includes temporary integer and floating point registers for holding intermediate calculations. Register file 24 handles both floating point and integer data. Integers are positioned in the lower order 32 bits of the register file 24 <31:0>. Higher order bits <40:32> are not implemented in the integer registers of the register file 24. The register file 24 functions the same for integer or floating point data. Register file 24 receives results of executed and nonspeculative operations from the reorder buffer 26 over four writeback busses 34, in a process known as retiring results.
Reorder buffer 26 is a circular FIFO for keeping track of the relative order of speculatively executed ROPs. The reorder buffer storage locations are dynamically allocated, for sending retiring results to register file 24 and for receiving results from the functional units. When an instruction is decoded, its result value is allocated a location, or destination, in the reorder buffer 26, and its destination-register number is associated with this location. For a subsequent operation having no dependencies, its associated A and B operand busses 30 and 31 are driven from the register file 24. However, when a subsequent operation has a dependency and refers to the renamed destination register to obtain the value considered to be stored therein, an entry is accessed within the reorder buffer 26. If a result is available therein, it is placed on the operand bus. If the result is unavailable, a tag identifying this reorder buffer entry is furnished on an operand tag bus of A and B-operand tag busses 48 and 49. The result or tag is furnished to the functional units over the operand busses 30, 31 or operand tag busses 48, 49, respectively. When results are obtained from completion of execution in the functional units 20, 21, 22 and 80, the results and their respective result tags are furnished to the reorder buffer 26, as well as to the reservation stations of the functional units, over five bus-wide result busses 32 and result tag busses 39.
Results generated by functional units are communicated to reorder buffer 26 using five 41-bit result busses 32 and five associated result tag and status busses 39. Of the five result and result tag and status busses, four are general purpose busses for forwarding integer and floating point results to the reorder buffer. Additional fifth result and result tag and status busses are used to transfer information, that is not a forwarded result, from some of the functional units to the reorder buffer. For example, status information arising from a store operation by the load/store functional unit 80 or from a branch operation by the branch unit 20 is placed on the additional busses. The additional busses are provided to conserve bandwidth of the four general purpose result busses.
The instruction decoder 18 dispatches ROPs "in-order" to the functional units. This order is maintained by the order of entries within reorder buffer 26. The functional units queue ROPs for issue when all previous ROPs in the queue have completed execution, all source operands are available either via the operand busses or result busses, and a result bus is available to receive a result. Thus, the functional units complete ROPs "out-of-order". In this manner, the dispatch of operations does not depend on the completion of the operations so that, unless the processor is stalled by the unavailability of a reservation station queue or an unallocated reorder buffer entry, the instruction decoder 18 continues to decode instructions regardless of whether they can be promptly completed.
A suitable unit for a RISC core is disclosed in U.S. patent application Ser. No. 08/146,382 filed on Oct. 29, 1993 (David B. Witt and William M Johnson, "High Performance Superscalar Microprocessor," Attorney Docket Number M-2518), which is incorporated herein by reference in its entirety.
The instruction decoder 18 dispatches an integer ROP using a single dispatch position which specifies one A operand, one B operand and one destination register. Illustrative instruction decoder 18 dispatches a floating point ROP as two associated "half-ROPs", or more generally "sub-ROPs", so that two associated A-operands and two associated B-operands are allocated as "half-operands", or "suboperands". The floating point half-operands are pictorially illustrated by FIG. 2. A full floating point register 250, shown in FIG. 2, is allocated in the form of two half-operands, shown by the first and second floating point half-operands 256 and 258. For an A-operand, one of a pair of half-operands (e.g. 256) is placed in an A-operand position corresponding to a first associated floating point opcode. The second of the pair of half-operands (e.g. 258) is placed in an A-operand position corresponding to a second associated floating point opcode. Likewise, a pair of B half-operands is placed into B-operand positions that correspond to the pair of opcodes. Instruction decoder 18 initiates access to the A and B-operands via pointers 36 and 37 to register file 24 and reorder buffer 26. Instruction decoder 18 dispatches half-ROPs to floating point functional unit 22 by communicating "half-opcodes" on two of the four opcode/type busses 50. For a floating point instruction, decoder 18 concurrently dispatches, in a single dispatch window, two ROPS having the two sets of A and B half-operands from, respectively, two of the four dispatch positions.
In an illustrative embodiment, opcodes for the two floating point half-ROPs are designated as a "dummy" opcode and an associated "actual" opcode. For example, a dummy floating point opcode (e.g. FPFILL) is allocated A and B half-operands, each associated with bits <40:0> of the full 82-bit floating point A and B operands, in one dispatch position of the dispatch window. In the immediately following dispatch position of the window, the actual floating point operation code is allocated A and B half-operands, each associated with bits <81:41> of the full floating point A and B operands. When floating point functional unit 22 executes the ROP, it merges the half-opcodes to execute a single ROP. For example, a floating point add instruction, FADD, may be dispatched in the following manner:
______________________________________ OPCODE/DISPATCH POS TYPE A-OPERAND B-OPERAND______________________________________1 FPFILL <40:0> <40:0>2 FADD <81:41> <81:41>3 -- -- --4 -- -- --______________________________________
Other ROPs may be dispatched in window positions 3 and 4. A half-ROP pair is dispatched in one window.
In other embodiments, a processor 10 may divide the operands into more than two sub-operands. For example, rather than segmenting an operand field into two half-operands, an operand may be divided into three or more suboperands which are operated upon via the dispatch of a like number of sub-ROPs.
Reorder buffer 26, register file 24, non-floating point functional units and various busses, including operand, tag, result and writeback busses, handle floating point half-ROPs as two independent and unrelated ROPs. However, instruction decoder 18, which segments half-ROPs, and floating point functional unit 22, which recombines half-ROPs prior to execution, treat half-ROPs as related entities. In this manner, floating point operands are communicated among the floating point unit and other functional blocks on integer data paths.
A detailed illustration of the register file 24 is shown in FIG. 3. The register file 24 includes a read decoder 60, a register file array 62, a write decoder 64, a register file control 66 and a register file operand bus driver 68. The register file array 62 includes multiple addressable storage registers for storing results operated upon and generated by processor functional units. FIG. 4 shows an exemplary register file array 62 with forty registers, including eight 32-bit integer registers (EAX, EBX, ECX, EDX, ESP, EBP, ESI and EDI), eight 82-bit floating point registers FP0 through FP7, sixteen 41-bit temporary integer registers ETMP0 through ETMP15 and eight 82-bit temporary floating point registers FTMP0 through FTMP7 which, in this embodiment, are mapped into the same physical register locations as the temporary integer registers ETMP0 through ETMP15.
Referring to FIG. 5, reorder buffer 26 includes a reorder buffer (ROB) control and status block 70, a reorder buffer (ROB) array 74, and a reorder buffer (ROB) operand bus driver 76. ROB control and status block 70 is coupled to the A and B-operand pointers 36 and 37 and the destination pointer (DEST REG) busses 43 to receive inputs which identify source and destination operands for an ROP. ROB array 70 is coupled to the result busses 32 to receive results from the functional units. Control signals, including a head, a tail, an A operand select, a B operand select and a result select signal, are conveyed from ROB control and status 70 to ROB array 74. These control signals select ROB array elements that are written with result busses 32 data and read to writeback busses 34, write pointers 33, A and B-operand busses 30 and 31, and A and B-operand tag busses 48 and 49. The A operand select and B operand select signals are applied to the reorder buffer array 74 to designate operand data to be placed on the operand busses 30 and 31. The A operand select and B operand select signals are also applied directly to the reorder buffer operand bus driver 76 to drive the A and B-operand tag busses 48 and 49, when data is not available in the register file 24 or the reorder buffer 26. Sixteen destination pointers, one for each reorder buffer array element, are conveyed from ROB array 74 to ROB control and status 70 for implementing dependency checking.
ROB array 74 is a memory array under the control of the ROB control and status block 70. As the instruction decoder 18 dispatches ROPs, it places pointers on the four destination pointer (DEST REG) busses 43. ROB control status 70 then allocates an entry of ROB array 74 and writes the destination pointer into the DEST PTR field of the allocated entry.
As operations are executed and results are placed on the result busses 32 by the functional units, ROB control and status 70 accesses pointers from the result tag busses 32 which designate the corresponding ROB array entries to receive data from the result busses 32. ROB control 70 directs writing from the result busses 32 to the ROB array 74 using four result select pointers.
FIG. 6 depicts an example of a reorder buffer array 74 which includes sixteen entries, each of which includes a result field, a destination pointer field and other fields for storing control information. A 41-bit result field is furnished to store results received from the functional units. Two reorder buffer entries are used to store a floating point result. Integer results are stored in 32 of the 41 bits and the remaining nine bits are used to hold status flags.
The destination pointer field (DEST PTR<8:0>) of each ROB array 74 entry designates a destination register in register file 24. Data from the result field is communicated from an ROB array 70 entry to the register file 24 via one of the writeback busses 34 and driven into the designated destination register during write-back by placing the destination pointer field onto a pointer of the writepointers 33. ROB control and status 70 receives the operand pointers and the destination pointer from instruction decoder 18 via, respectively, the A and B-operand pointers 36 and 37 and the destination register (DEST REG) busses 43, and writes the destination pointer in the destination pointer (DEST PTR<8:0>) field of the ROB array 74. When an ROP is dispatched, reorder buffer 26 accomplishes dependency checking by simultaneously testing the destination pointer (DEST PTR<8:0>) fields of all sixteen elements of reorder buffer array 74 against A and B-operand pointers 36 and 37 to determine whether a match, identifying a data dependency, exists between a destination pointer and the A or B-operand pointers.
When ROB control and status 70 detects a data dependency at dispatch, it overrides the reading of any dependent operand in a register file array 62 entry by setting bits of an A operand override bus 57 and a B operand override bus 58 which are applied to the register file operand bus driver 68. Override busses 57 and 58 include override signals for each operand bus. If ROB control and status 70 determines that a source operand is available in either register file 24 or reorder buffer 26, the source operand is placed on a bus of operand busses 30 or 31 for access by the functional units.
ROB control and status 70 retires an ROP by placing the result field of an ROB array 74 element on one of the writeback busses 34 and driving the write pointer 33 corresponding to the writeback bus with the destination pointer. Write pointer 33 designates the register address within register file 24 to receive the retired result. For write-back of integer data, low order 32 bits <31:0> of the result hold integer data, while high order bits <37:32> are error flags EFLAGS 71 used to update a status flags 25. For floating point data, separate status busses 38 communicate flags to the reorder buffer 26, where the flags are stored until they are conveyed to a floating point status register (not shown) when the floating point ROP is retired.
Each reorder buffer array 74 element 220, depicted in FIG. 7, includes a 41-bit result field 101, a 9-bit destination pointer field 102, a 4-bit delta PC field 103, an 11-bit floating point operation code field 104, an 11-bit floating point flag register field 105 and a 24-bit status/control field 106. For floating point operands, result field 222, shown in FIG. 8, holds a 41-bit "half-result" of the floating point operation. For integer operations, bits <40:32> of the 41-bit result field hold integer flag registers as is shown in result fields 224, 226 and 228 of FIGS. 9, 10 and 11, respectively. For integer operations yielding results having widths of 8 or 16 bits, additional bits are cleared by the functional unit that generates the result in the form depicted in result fields 228 and 226 of FIGS. 10 and 11, respectively.
For branch operations, result field 230 shown in FIG. 12 holds the logical address of the program counter as determined by execution of a branch ROP by branch unit 20.
Referring to FIG. 7, destination pointer field 102 specifies a destination register of register file 24. Floating point opcode field 104 is set to a subset of the bits of a floating point operation code allocated to a reorder buffer entry. The floating point flag register field 105 holds the state of the floating point flags arising from a floating point operation. Floating point flags hold information relating to precision, underflow, overflow, zero divide, denormalized operand and invalid operand errors detected by the floating point functional unit 22. For integer operands, a corresponding flag field is not necessary since flags arising from integer operations are held in bits <40:32> of the 41-bit result field 101. Status/control field 106 denotes the status of the operand, for example, whether a ROB entry is allocated, a branch is incorrectly predicted or performance of an operation has caused an exception or error condition.
FIG. 13 depicts a schematic layout diagram of a mixed floating point/integer core with a 41-bit data path traversing register file 24, reorder buffer 26 and floating point functional unit 22. This data path includes the A and B-operand busses 30 and 31, the result busses 32 and the writeback busses 34. Only bits <31:0> of the A and B-operand busses 30 and 31 are interconnected with the integer functional units, such as unit 21. The lines of the busses are shown superimposed upon the register file 24, reorder buffer 26 and integer units 110 to illustrate that the data path has a bit-by-bit correspondence for the data lines of the busses and memories in the other functional blocks. The lines of the busses are shown extending only partially into the floating point functional unit 22 to illustrate that the bit structure of the busses extends only into the floating point reservation stations and result driver. In the operational interior of the floating point functional unit 22, pairs of 41-bit operands are combined into the 82-bit extended form for processing.
The four respective pairs of 41-bit A and B-operand busses 30 and 31 interconnect among the functional units, reorder buffer 26 and register file 24 and extend from the floating point functional unit 22 reservation stations, across the integer units and the reorder buffer 26 and substantially across the register file 24. The areas of the core that contain the integer units and underlie bits <31:0> of the operand busses include reservation station registers for holding the operand data. Bits <41:32> of the A and B-operand busses 30 and 31 pass by the integer units without interconnecting with the units.
The five 41-bit result busses 32 interconnect among the functional units and reorder buffer 26 and extend from the floating point functional unit 22 result bus drivers, across the integer units and substantially across the reorder buffer 26. Essentially all of the 41 bits of the result busses 32 interconnect with the integer units so that result data is communicated in bits <31:0> and integer status flags are communicated in bits <41:32>. In the illustrative embodiment of the microprocessor the number of defined status bits utilize only bits <37:32> of the result busses 32.
The four 41-bit writeback busses 34 communicate result data from reorder buffer 26 to register file 24 and extend substantially from one side of the reorder buffer 26 substantially to the opposite side of the register file 24.
It is advantageous that, with few exceptions (e.g. operand bits <41:32> and result bus bits <41:38>), each bit of each bus in the data path only traverses a functional block with which it interconnects.
This layout represents a mixed floating point and integer core in which the total bus width (the sum of all bits) of all buses of the data path is substantially constant throughout the integer and floating point functional units.
The layout embodiment shown in FIG. 13 is advantageous because it yields a dense core. The floating point functional unit 22 and the register file 24 preferably are located at the ends of the core. The floating point functional unit 22 has its own internal bus structure, so that the A-operand busses 30, the B-operand busses 31, and the result busses 32 need not traverse it. Moreover, the floating point functional unit 22 is large, consuming about twenty percent of the core. Accordingly, positioning the floating point functional unit 22 such that the A-operand busses 30, the B-operand busses 31, and the result busses 32 are routed past it would unnecessarily consume die space. Similarly, the register file 24 does not use the result busses 32, so that the result busses 24 need not traverse it. Moreover, the register file 24 is large, consuming about thirty percent of the core. Accordingly, positioning the register file 24 such that the result busses 32 are routed past it would unnecessarily consume die space. The load/store functional unit 80, which consumes about twenty-five percent of the core, is located between the floating point functional unit 22 and the reorder buffer 26 because it is traversed by the A and B operand busses 30 and 31 and by the result busses 32. The integer units 110, including the branch unit 20, are located between the floating point functional unit 22 and the reorder buffer 26 because they are traversed by the result busses 32 and the bits <31:0> of the A and B operand busses 30 and 31. Bits <40:32> of the operand busses 30 and 31 bypass the integer units 110, however the adverse impact on the core density is minor, since the integer units 110 are relatively small, consuming only about ten percent of the core.
FIG. 13 also shows a floating point flag bus 38 which bypasses the integer units 110 to reach the reorder buffer 26. The adverse impact of the bus 38 on core density is minor, since it is only a single bus of eleven bits. Note that, because the integer flags are communicated on various 41-bit busses which are also used for floating point data transfer, advantageously thirteen separate 6-bit integer flag busses which would otherwise be associated with the eight operand busses 30 and 31 and the five result busses 32 are avoided.
While FIG. 13 shows a core having a constant 41-bit width data path across the floating point functional unit 22, the integer units 110, the load/store functional unit 80, the reorder buffer 26, and the register file 24, other core layouts may not have a constant data path width throughout but still benefit from having bus structures wide enough to accommodate both floating point data and the combination of integer data and integer flags. For example, in an alternative embodiment (not shown) in which the integer units are larger than the register file, the register file might be positioned within the core and the integer units might be positioned at one end of the core. In this event, the 41-bit pitch of the result busses 32 would be extended but only the bits <31:0> of the A and B operand busses need be extended. In this alternative layout, the A and B operand busses 30 and 31 and the result busses 32 would need to traverse or bypass the register file. However, advantageously the extension of bits <40:0> of the result busses 32 to the repositioned integer units would accommodate both floating point data and the combination of integer data and integer flags.
FIG. 14 is a block diagram that illustrates floating point connections of a processor embodiment in which the data path width is less than the internal data path width of the floating point functional unit 22. Preferably, the internal data path width of the floating point functional unit 22 is an integer multiple of the data bus width.
In the illustrative architecture, the operand 30 and 31, result 32 and writeback 34 busses are expanded from a 32-bit data path to a 41-bit data path to accommodate one-half of an 82-bit extended precision floating point variable. Integer ROPs are dispatched in the same manner as a purely integer implementation when the data path is expanded. However, operands associated with ROPs are assigned to bits <31:0> of the four pairs of A and B-operand busses 30 and 31. When integer operands are loaded onto the busses, high order nine bits <40:32> are not used to communicate integer data, while low order 32 bits <31:0> encode the integer data and communicate it to an integer functional unit. When a floating point ROP is dispatched, all 41 bits communicate data to a floating point reservation station 44, which combines the two half-ROPs and locally merges 41-bit operands to form an 82-bit operand. 82-bit operands are sent to a floating point arithmetic circuit 100 internally via two 82-bit floating point operand busses 90 and 91 and communicated from the arithmetic circuit 100 to floating point result drivers 45 on an 82-bit floating point result bus 92. Standard extended precision numbers are 80 bits wide, although two extra bits in the exponent field may be applied to accommodate a greater data range of internal floating point numbers.
Floating point flags communicate over a FP flag bus 112. Because there is only a single floating point function unit 22 within the processor 10, a single FP flag bus 112 is sufficient and the routing and placement of the floating point functional unit 22 and the floating point flag bus 112 is improved. Although integer functional units 110 also generate flags, corresponding integer flag busses are not necessary because result bus 32 bits <40:32>, which would otherwise not be utilized, are employed to communicate integer flags. Communicating integer flags over 41-bit busses is advantageous for preventing inclusion of additional dedicated integer flag busses which complicate processor layout and consume die space.
When source operands are available and two result busses are available, the reservation station 44 issues the ROP, such as a floating point multiply, divide or other ROP-specified operation, and the arithmetic circuit 100 calculates an 82-bit result. Floating point result drivers 45 divide the 82-bit result into 41-bit segments, places the segments onto two of the four general purpose result busses 32 and sets flags on the status busses 38. The floating point functional unit assigns the high order bits <40:32> of a floating point result to correspond to the least significant nine bits of a floating point number, even though they are numbered in the higher bit positions. This is done because shifting the data field in this manner allows the sign and exponent of the high order 41-bits of floating point data to be read in a 32-bit integer data access.
Various integer functional units, which are depicted in combination as integer units 110, operate on 32-bit data. Integer units 110, in addition to writing a result to bits <31:0> of the result busses 32, write result flags to bits <40:32> of the result busses 32. The result busses 32 are connected to the reorder buffer 26, which temporarily stores the result data. Reorder buffer 26 retires the 41-bit result to register file 24 without regard for whether data are floating point or integer.
FIG. 15 depicts bit fields of a standard 82-bit floating point number. Most significant bits <81:42> represent a sign bit 241, a 19-bit exponent field 242 and the high order 21 bits of the 62-bit significand field 244. The significand field of a floating point number represents an integer number, which is multiplied by two raised to the power designated by the exponent field. The processor 10 of the present embodiment configures floating point numbers in the manner illustrated in FIG. 16, in which an 82-bit field 250 is separated into two 41-bit fields. In the high order 41-bit field, the 9 least significant of significand bits <59:41> are shifted to a significand field <81:73> 254. A sign field 251 and an exponent field 252 are shifted nine bits lower in significance. In the low order 41-bit field of the floating point bits 250, a significand field <8:0> is shifted into high order bits <40:32> and a significand field <40:9> is shifted into low order bits <31:0> of the 41-bit field.
82-bit floating point register 250 is segmented into first floating point half-operand 256 and second floating point half-operand 258. Second floating point half-operand 258 is shifted right by nine bits and significand bits <49:41> 254 are transferred to the most significant bit locations. Thus sign 251 and exponent <16:0> 252 are readable and writable in a 32-bit integer access.
Load/store functional unit 80 controls integer and floating point load and store operations. Load/store unit 80 can simultaneously execute up to two load operations for accessing data from the data cache 86 and forwarding the data to result busses 32. Referring to FIG. 17, load/store functional unit 80 includes a reservation station 82, a store buffer 84 and a load/store control 87. The load/store reservation station 82 is dual ported. Each port is connected to the store buffer 84 and the data cache 81 by a channel, which comprises 40-bits of data and a suitable number of address bits. Load/store reservation station 82 is a FIFO buffer which queues load/store requests. It receives operation codes from opcode/type busses 50 and operates upon results on the A and B-operand busses 30 and 31 that are multiplexed at the input to load/store reservation station 82.
A mixed integer and floating point structure allows the processor to perform loading and storing operations for both integer and floating point data using the same load/store functional unit 80. Within the load/store functional unit, the data operands are 41-bit and represent either an integer, a single precision number, part of a double precision number or part of an extended precision number. For integer data, the most significant eight bits are not used. Load/store functional unit 80 functions in the same manner for both integer and floating point operands. Therefore, by mixing the integer and floating point data path, only a single load/store functional unit 80 is used, reducing the amount and complexity of processor circuitry. A suitable load/store unit is disclosed in U.S. patent application Ser. No. 08/146,376 filed on Oct. 29, 1993 (William M. Johnson et al., "High Performance Load/Store Functional Unit and Data Cache," Attorney Docket Number M-2281), which is incorporated herein by reference in its entirety.
While the invention has been described with reference to particular embodiments, it will be understood that the embodiments are illustrative and that the invention scope is not so limited. Many variations, modifications, additions and improvements to the embodiment described are possible. For example, rather than segmenting an operand field into two half-operands, an operand may be divided into three or more suboperands that are operated upon via the dispatch of a like number of suboperations, which are consolidated into a single operation prior to its execution. Furthermore, the number of bits in the various structures and busses is illustrative, and may be varied. The size of the register file and the reorder buffer, the number of operand buses and operand tag busses, the number of result buses, the number of writeback buses, and the type and number of functional units, such as the number of floating point functional units, are illustrative, and may be varied. These and other variations, modifications, additions and improvements may fall within the scope of the invention as defined in the following claims. | A processor core for supporting the concurrent execution of mixed integer and floating point operations includes integer functional units (110) utilizing 32-bit operand data and a floating point functional unit (22) utilizing up to 82-bit operand data. Eight operand busses (30, 31) connect to the functional units to furnish operand data, and five result busses (32) are connected to the functional units to return results. The width of the operand busses is 41 bits, which is sufficient to communicate either integer or floating point data. This is done using an instruction decoder (18) to apportion a floating point operation which operates on 82-bit floating point operand data into multiple suboperations each associated with a 41-bit suboperand. The operand busses and result busses have an expanded data-handling dimension from the standard integer data width of 32 bits to 41 bits for handling the floating point operands. The floating point functional unit recombines the suboperand data into 82-bits for execution of the floating point operation, and partitions the 82-bit result for output to the result busses. In addition, the excess capacity of the result busses during integer transfers is used to communicate integer flags. | 6 |
BACKGROUND OF INVENTION
[0001] 1. Field of the Invention
[0002] The invention concerns a device for gripping and transferring a ring of electrical conductors in the form of pins, used to produce a winding, such as a pin winding, for the stator of a rotating electrical machine; the gripping device is adapted to seize the ring from a first device, such as a ring-forming element, and transfer it to a second element, such as an element to insert the ring in the element holding the winding to be produced.
[0003] The invention also concerns a system for producing a winding on a carrying element, such as the stator with a pin winding of a rotating electrical machine, that includes a ring support element which has axial notches in its internal radially cylindrical face and a winding formed by many electrical conductors, each in the form of a pin that has two prongs connected by a head which are mounted in series, the intermediate straight sections of which are placed in two notches that are angularly set off from each other by a predetermined angle, while the head parts generally in the form of a U and the ends of the prongs are wound as a result to obtain from one axial side of the support element a chignon formed by the heads of the pins and from the other side a chignon formed by the free combined ends of the pins; this system is the type that includes a first element to place the pin-shaped conductors in the form of a ring of conductors and to wind the heads of the pins, a device for gripping the ring of conductors with wound pin heads and for transferring this ring to a second device in which this ring is inserted in the winding support element.
[0004] 2. Background Art
[0005] A system for producing a stator with a pin winding and a gripping device to remove and insert the pins, as defined above, is known through patent application WO 92/06527. The gripping device described in this document constitutes an independent transfer device that can be separated from said first and second devices. The disadvantage of this device lies in the fact that it acts on the heads of the pins.
[0006] To eliminate this disadvantage, one may consider using an arrangement of the type described in document GB-A-2 047 055 which uses a control device in the form of a case within which is mounted a cup. The case is mounted and movable in relation to the cup and acts on gripping levers. The cup has grooves to allow the passage of the levers, which are mounted with a joint on the cup, to move between a position for gripping the ring and an open position for releasing the ring.
[0007] The levers have two arms, one of which is a pivot control arm with a spherical control end installed in a circular groove of the frame and the other has ring-gripping elements at the end. The levers are mounted in such a way as to pivot on a ring element forming the frame, i.e. the cup, through their intermediate section located between the two arms.
[0008] Because of the presence of the case groove, there is a risk that the levers will jam.
SUMMARY OF INVENTION
[0009] The purpose of this invention is to correct this disadvantage.
[0010] According to the invention, the control elements include an element in the form of a cone coaxial to the frame which has an outside peripheral surface that is inclined in relation to the axis of the frame, which can be axially moved in the frame under the effect of a movement control device in the control cone and in that the ends of the control arms of the levers are maintained in support on the inclined surface so that the axial displacement of the cone causes the pivoting of the levers.
[0011] Using the cone according to the invention, the control devices are simplified and the risks of the levers sticking are reduced. In addition, the levers are simplified because the control arms have one end in local contact with the control cone, which is simple and economical to produce.
[0012] In addition, first, the displacement of the levers is more precise because of the cone, the slope of which depends on the applications and, second, the lever-gripping end is simplified because of the fact that the cone is coaxial in the frame.
[0013] In effect, the levers are longer because they are mounted to pivot through their intermediate section located between the two arms in a radial plane; the ring is maintained by the levers in a coaxial position in the frame.
[0014] In one form for producing it, the intermediate section is formed by the middle part of the levers
[0015] According to one characteristic, for good pivoting of the levers, the intermediate section of the levers is mounted inside a cavity that is generally toroid in form that is part of the frame. This cavity is delimited by parts belonging to the frame. The parts present, for each lever, a slot for the passage of the lever arms.
[0016] These parts form a generally toroidal section that is hollow inside and they present an internal surface that is at least partially curved in a circle arc to allow the rotation of the intermediate sections of the levers which have spindles for this purpose
[0017] Of course, the parts have slots for the passage of the lever arms.
[0018] According to another characteristic of the invention, for reliable displacement of all the levers, the ends of the control arms of the levers are maintained in support against the inclined surface of the lever pivot control cone through an elastic toroid joint arranged in a ring groove that is coaxial to the frame and the joint is formed by notches in the outside surface of the ends of the control arms.
[0019] According to another characteristic of the invention, to facilitate gripping the pins, at least some of the ends of the gripping arms of the levers have lateral pins to ensure clamping of the straight prongs of the pins on the ring of conductors of the winding to be formed against a support surface of the frame when the levers are in the clamping position.
[0020] According to another characteristic of the invention, the ends of the lever gripping arms are configured to penetrate between the straight prongs of the ring pins which are adjacent to the ring in the peripheral direction when the levers pivot in their gripping position.
[0021] According to another characteristic of the invention, the gripping and transfer device has handling grips.
[0022] According to another characteristic of the invention, which is simple and economical, the axial displacement control device of the cone is formed by a cylinder between the cone and the frame.
[0023] According to another characteristic of the invention, predetermined positioning elements on the aforementioned first and second devices are advantageously made in the form of tubular elements or small columns designed to work with additional small columns or tubular elements installed on said devices.
[0024] The system of the invention is characterized in that the gripping and transfer device is made in the form of an autonomous device that can be positioned on said first and second devices in a predetermined position and can be separated from these devices; the gripping and transfer device and said first and second devices include marking elements for a defined, predetermined positioning of the gripping and transfer device in relation to the first and second devices.
[0025] According to one characteristic of the system in the invention, the aforementioned first and second devices form independent and separate work stations.
[0026] According to another characteristic of the invention, the system includes a gripping and transfer device as defined above.
[0027] According to another characteristic of the invention, the aforementioned positioning mark elements are formed by at least two tubular elements or small columns which are installed respectively on the gripping and transfer device and, second, on the work stations, and is characterized in that the tubular elements are intended to be fit together on the small columns when the transfer device is placed on the work stations.
BRIEF DESCRIPTION OF DRAWINGS
[0028] The invention will be better understood, and other purposes, characteristics, details and advantages of the invention will appear more clearly in the following explanatory description by reference to the attached schematic drawings, given only as an example, illustrating a method for producing the invention, in which:
[0029] FIG. 1A is a view in perspective of a station to wind the pin heads of a ring of conductors in the form of pins that are to form a stator winding according to the invention, and shows the pin heads after the wind-up.
[0030] FIG. 1B is a stripped schematic view illustrating the arrangement of the pins in the wind-up station for the pin heads before the wind-up operation.
[0031] FIG. 2 is a perspective view of the wind-up station according to FIG. 1 , but shows the ring in its position for gripping and withdrawal from this station.
[0032] FIG. 3 is a perspective of the transfer device according to the invention, in its engaged position on the ring according to FIG. 2 .
[0033] FIG. 4 is a perspectives of the transfer device after gripping and removal of the ring from the wind-up station.
[0034] FIG. 5 is a schematic view showing the operation for gripping the ring by the transfer device.
[0035] FIG. 6 is a perspective of the station that inserts the ring with wound pin heads, according to the invention, in a stator body.
[0036] FIG. 7 is a perspective of the transfer device according to the invention and of the insertion station according to FIG. 6 , during the insertion of the ring with wound pin heads.
[0037] FIG. 8 is a section view according to line VIII-VIII of FIG. 7 .
[0038] FIG. 9 is a section view similar to FIG. 8 , but shows the transfer device after the release of the ring inserted in the stator body
[0039] FIG. 10 is a perspective showing the ring, without the exits of the phases of FIG. 2 , after its insertion in a stator body according to FIG. 9 and after the start of the transfer device.
DETAILED DESCRIPTION
[0040] The invention will be described in its application to a system for producing a stator of a rotating electrical machine, such as an alternator for an automobile, which is equipped with a bearing annular element in the form of a stator body for mounting a winding formed by many conductors in the form of pins mounted in series. The pins contain two prongs connected by a curved head and are thus generally in the shape of a U. The pins cross with their prongs the body of the stator and form networks called chignons at the two ends of the body of the stator. One of the chignons is formed by the heads of the pins, and the other by the united (by welding, for example) free ends of the prongs of the pins connected to each other according to a specific configuration. The ring-shaped body of the stator is formed, by convention, by a packet of sheets equipped with axial notches for mounting the prongs of the pins.
[0041] The system according to the invention contains a first station A in which the heads of the pins with the overall structure of an annular ring are wound, as known, and a second station B in which the ring, after the first winding of the pin heads is inserted in the stator body and the free ends of the prongs of the pins are wound, as well as a device C to transfer and grip the pin ring after the first winding of the pin heads from the first station A to the second station B. For more details, refer, for example, to document WO 92/06527 describing the winding of the stator and its mounting in the body of the stator of an automobile alternator. The gripping device according to the invention is applicable to the winding of this document.
[0042] As shown in FIGS. 1A and 1 b , the conductors in the form of a pin, designated by the general reference 1 , are arranged in a device with two rotating coaxial tools 3 and 4 , which have on the opposite surface notches 5 and 6 , each intended to receive one of the two straight prongs 8 of two conductors in pin shape 1 . After the insertion of the conductors in the notches of the stator body, the two tools turn in opposite directions, as illustrated by arrows, in a predetermined angle to obtain the desired winding of the heads 10 of the generally U-shaped pins
[0043] Advantageously, station A is equipped with an upper plate (not shown), but known, for example, through document WO 92/06527 cited above, with protrusions for the formation of spacers for the upper ends of the pins. Station A also contains, which is also known, cams (not shown) which are used to push the pins axially to release a part of the right prongs indicated by reference 11 so that the winding can be seized by the transfer device C.
[0044] According to a characteristic of the invention, the fixed part of this station contains small positioning columns 12 on station A of the transfer device B which will be described below.
[0045] Referring to FIGS. 7 to 9 , the transfer and gripping device C essentially contains a fixed frame 13 to support a number of articulated blades 15 , each in the form of a lever with two arms 16 , 17 , a control cone 19 for pivoting the levers 15 , which is mounted axially and moves in the frame 13 , and a control device to move the cone 19 , made in the form of a valve 21 (hydraulic here), the cylinder of which 22 is mounted on an upper cover plate 25 of the cone 19 , while the cylinder rod 26 is attached to a console 27 at the base of the frame 13 . As a variant, the cylinder is electric. The levers 15 are mounted to pivot on the frame through their middle section 18 placed between the two arms. Here section 18 is a middle part; the arms 16 , 17 are basically equal. In a variant, one of the arms is longer than the other. In the figures, the middle part 18 is in the form of a circular section so that it forms a cylindrical spindle, and is mounted to pivot in the frame 13 . The levers 15 pivot through their middle section in a radial plane; the annular ring is maintained by the levers in a position coaxial to the frame.
[0046] This frame contains a central sleeve 28 with a circular transversal section, the lower end of which is joined (by screwing) to the console 27 . Attached to the other end (here using a screw), through a part in the form of a coupling 30 , is a hollow ring part 31 used to house the circular middle sections 18 of the levers 15 . The internal face of part 31 is at least partially curved at 32 in a circle arc to allow the rotation of these middle parts 18 . The coupling 30 is extended, here in a single piece, through a hollow annular part 130 that has an internal face that is also partially curved at 132 in a circle arc to allow the rotation of the middle section 18 of the levers 15 .
[0047] The internal face of the hollow section 130 of the coupling 30 is axially and transversally offset from the internal face of part 31 . Thus, part 31 delimits, with the hollow section 130 of the coupling 30 , an annular cavity, here generally toroidal in form, to house the middle sections 18 . Thus, an annular part 130 , 31 is toroidal in form with an upper wall belonging to part 31 and a thicker, lower wall belonging to the hollow section 130 of the coupling 30 . The upper and lower walls are parallel to each other and are oriented transversally in relation to the axial axis of symmetry X-X of the transfer and gripping device C. The X-X axis is also the axial axis of symmetry of the cylinder 19 and of the layout of the levers 15 .
[0048] Here the upper wall of part 31 is connected through a wall in the form of a circle arc, with a curved surface on the inside 32 , with an axially oriented cylindrical ring 29 , while the lower wall of the section 130 is connected through a wall chamfered on the outside with a cylindrical ring 29 with an axial orientation for connection to the coupling 30 . The ring 29 surrounds the ring of part 130 , the exterior chamfered wall of which has the face 132 on the inside in the form of a circle arc. Part 31 and section 130 are thus mounted in the opposite way.
[0049] The toroidal core 31 , 130 contains, for each lever 15 , a slot 33 in its upper and lower walls for the passage of the arms 16 and 17 of the levers. Each slot 33 has a width slightly greater than the width of the corresponding lever and is long enough to allow the lever to pivot.
[0050] The pivot control cone 19 for the levers 15 has, at the end opposite the end capped by the plate 25 , a coaxial end with a circular transversal section 36 , which is mounted axially and slides in the sleeve 28 of the frame 13 , under the action of the actuating cylinder 21 .
[0051] The transfer device C has a number of pivoting levers 15 ; this number is equal to the number of pin-shaped conductors 1 of the rotor winding to be produced. As can be seen on FIGS. 8 and 9 , the ends 38 of the upper control arms 16 of the levers 15 are curved in the direction of the X-X axis of the transfer device and are support by their rounded end surface on the peripheral conical surface 40 of the control cone 19 . The cone shrinks from top to bottom. The free tab-shaped end 42 of each lower gripping arm 17 of a pivoting lever 15 is bent in the direction of the X-X axis. The bent ends extend perpendicularly to the X-X axis, with a width that allows them to penetrate between the straight prongs 11 of two adjacent pin conductors 1 .
[0052] As FIG. 5 shows, one out of two of the ends 42 is configured in a gripping tab by associating pins 43 with it that extend laterally on either side. These pins are located at a distance from the free end edge 44 of the tab to ensure a gripping effect by clamping the four straight radially aligned pins 11 of the winding located between two adjacent ends 42 , between a pin 43 and a support surface 46 of the frame of the transfer device, which is formed by the cylindrical outside peripheral surface, with an axial orientation, of the console 27 made for this purpose in the form of an upside down cup. The pins 43 are located at the junction between the tab 42 that carries them and the rest of the lever arm 17 .
[0053] As shown on FIGS. 8 and 9 , to ensure proper operation of the levers, the centers of the circular central sections 18 of the levers are on a circle coaxial to the X-X axis of the device, the diameter of which is greater than the outside diameter of the ring formed by the straight prongs 11 of the pins 1 .
[0054] According to an important characteristic of the invention, each lever 15 has, at its upper support end 38 on the surface 40 of the cone 19 , on the outside surface, a notch 48 so that all the notches 48 form an annular groove in which is placed an elastically stretchable seal 50 , the function of which is to maintain the support ends 38 on the conical surface 40 of the control cone 19 . As a result, when the cylinder 21 moves the control cone 19 from its upper position to the bottom, the levers 15 pivot between a maximal spread position of the tabs 42 of the X-X axis and a closed position for gripping the winding ring to be transferred from station A to station B
[0055] According to another important characteristic of the invention, the transfer device C contains, arranged opposite each other around the diameter, two handling grips 52 which are each attached to the outside peripheral surface 53 of the ring 29 of part 31 of the frame 13 by an intermediate part 54 which carries a tubular part 55 with an axis parallel to the X-X axis of the device. The two tubular parts 55 are arranged so that they can engage on the small columns 13 of the winding station A and ensure, working with these small columns, a precisely defined positioning for the transfer device on the winding ring as produced in station A.
[0056] Station B contains, as shown on FIGS. 6 to 10 , a support base 58 for an annular stator body as designated by reference 60 on FIGS. 8 and 9 . To ensure a centered position for the stator body on the base, the base has an outside centering washer 61 and an interior centering part 62 . The body of the stator is then arranged between the washer and the central part 62 , as shown on FIGS. 8 and 9 . The washer 61 and the part 62 are screwed here onto the base 58 .
[0057] The base 58 of station B has, on its upper surface, two small columns 64 for positioning the transfer device C, which are arranged so that they each engage a centering element 55 of this device. The small columns are surrounded by exchangeable, tubular support elements 65 for the front surfaces of the centering elements 55 . All this is made possible by the cone 40 and the annular part 31 .
[0058] It should also be noted that station B is also equipped with four concentric tools (not shown) for winding the straight pins 11 of the winding ring after the insertion in the grooves of the body of the stator and driving in the pins. Since this second winding operation and the tools used for this purpose are known, the tools will not be described in more detail.
[0059] We will describe below the operation of the stator-producing system that has just been described.
[0060] In the first winding station A, after the insertion of the pin-shaped conductors 1 into the notches 5 , 6 of the two rotating tools 3 and 4 , which then form a ring of pins, the tools are turned in the opposite direction to perform the winding of the pin heads. Then, through the action of ejection rods, the pins on which the prongs are still straight are pushed again until there is only a small part engaged in the winding tools.
[0061] Then, the transfer station C is moved to winding station A and is positioned on this station by passing the centering tubes 55 onto the positioning small columns 12 of station A. The levers 15 of the device C are then in their position away from the X-X axis, and the support cone 19 is in its high position.
[0062] After the correct positioning of device C on station A, the cylinder 21 is activated so that it moves the support cone 19 toward the bottom, which pivots the levers 15 into their position for gripping the winding ring still retained in station A. This pivoting forces the tabs 42 of the arms of lever 17 to penetrate between the straight prongs of the pin conductors until one out of two of the rows of four prongs are encircled between the pins 43 and the support surface 46 of the console 27 of the transfer station frame ( FIG. 5 ). Then the transfer station C is moved vertically upward along the positioning small columns 12 and removes the winding ring from station A, then the prongs of the pins remain trapped in the transfer device.
[0063] Then the transfer device C is moved with the winding ring trapped, as shown in FIG. 4 , to the second station B, and this device is positioned on the station by threading the centering tubes 55 onto the positioning small columns 64 of this device. During this threading, which ensure the correct relative position of the transfer device C and of the winding ring in relation to the stator 60 , which was previously placed in station B, the ends of the straight prongs of the pins penetrate the notches of the stator body, as shown in FIG. 8 . Then, the gripping tabs 42 of the levers 15 are spread out, which release the ring held by the ends of the pins in the stator body by displacement of the support cone 19 upward using the cylinder 21 . In this open lever position, the transfer device C can be removed from station B.
[0064] Then, after driving the pins 1 into the body of the stator 60 , the ends of the pin prongs 11 are wound with the four concentric tools that are part of station B, as is known in the industry.
[0065] It should be noted that, thanks to the positioning of small columns 12 and 64 of stations A and B and the centering tubes 55 which can be threaded onto these small columns, of the transfer device C, stations A and B can be independent and separated from each other and the pin ring, after the first winding at station A, can be carried by the transfer device C to station B, without risk of the loss of the correct positioning marks on the ring in relation to the body of the stator.
[0066] The invention can be used for the production of triphased windings or windings with two offset triphased systems, or with any number of offset triphased systems. The pin windings can have 2, 4, 6 or even more conductors per notch. The windings are particularly used advantageously for automobile alternators, particularly with 6, 7, 8 or 9 pairs of poles such as those described in application FR-A-2 819 117. This is why we see in FIGS. 1A and 2 the winding phase outputs and the neutral bars. With the invention, the presence of such neutral bars with a circumferential orientation and outputs with an axial orientation is possible; these outputs extend axially in relation to the heads. For more details, refer to this document. Of course, the invention is applicable to an automobile starter; in this case, the winding is the winding of a rotor that constitutes the bearing element. | The invention relates to a device for gripping and transferring a ring of electrical conductors in the form of pins which are used to produce a winding, such as a pin winding. The gripping device (C) is designed to seize the ring from a first element, such as a ring-forming element, and to transfer same into a second element (B), such as an element used to insert the ring into the member that supports the winding to be produced. The inventive device comprises a control cone ( 19 ) which can be moved axially inside a frame ( 13 ) for contact with levers ( 15 ) which are pivot mounted to the frame, such that the levers pivot when the cone is moved. The winding-production system is characterized in that it comprises an autonomous gripping and transfer device (C) which can be separated from the above-mentioned first and second elements (B) and which can be positioned on same in a pre-determined reference position. The invention can be used to produce a stator for an electrically-rotating machine. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This invention is a continuation in part of patent application Ser. No. 12/363,738, titled “Automated Partitioning of a Computation for Parallel or Other High Capability Architecture,” Ted J. Biggerstaff, Jan. 31, 2009, now U.S. Pat. No. 8,060,857.
Patent application Ser. No. 12/363,738, Titled “Automated Partitioning of a Computation for Parallel or Other High Capability Architecture,” Ted J. Biggerstaff, Jan. 31, 2009.
Patent application Ser. No. 12/766,894, Titled “Non-Localized Constraints for Automated Program Generation,” Ted J. Biggerstaff, Apr. 25, 2010.
FEDERALLY SPONSORED RESEARCH
Not Applicable
SEQUENCE LISTING OR PROGRAM
Not Applicable
BACKGROUND
1. Field of Invention
This invention relates to the automatic generation of programs where the automated generation systems are faced with the problem of creating and refining separated but constraint related parts of the program, where the separation of the parts may occur in both the time and space domain or just one of the two, where those parts are related by one or more non-local constraints (i.e., constraints that include all of the separated parts but perforce must span the separation gaps) such that those non-local constraints require that generator-based refinements or alterations of one of the constrained parts will determine and effect compensating generator-based refinements or alterations to the related parts so as to preserve the invariant properties of the overall constraint relationship and thereby preserve a consistent set of interdependencies among the parts, where such automatic generation systems provide various kinds of facilities for refining execution platform neutral specifications of computations into computer programs expressed in conventional programming languages such as, C, C++, Java and similar languages often referred to by the term General Programming Languages (or GPLs), and where such automatically generated computer programs are frequently required to exploit high capability facilities of such execution platforms including but not limited to fine grain, middle grain and large grain parallelism facilities, distributed facilities, security facilities, mobile facilities, remote services facilities, associated processing services facilities, situational facilities (e.g., awareness, position, movement, response, and so forth), quantum computing facilities and other or future high capability facilities.
2. Description of Prior Art
Adds Machinery Consistent with Previous Patent Application
This patent application enhances, supplements and extends the machinery of patent application Ser. No. 12/363,738 by introducing a new mechanism to couple separated elements of the target program being created by some domain specific generator (e.g., DSLGen, the reduction to practice generator of patent application Ser. No. 12/363,738) as well as to couple separated generative transformations that must coordinate their activities across separated generation times and separated target program locales.
Constraint Satisfaction Programming
Constraint satisfaction programming (or CSP) research is a sound-alike topic but it is NOT focused on using constraints to guide the construction and parallelization (or other program reorganization techniques) of general computer programs in the sense considered in this invention. And more specifically, it is not focused on dealing with explicitly coupled constraints on specific objects (i.e., program parts) and explicitly coupled transformations on specific, separated program parts where the constraints, their separated data and the related transformations inhabit a special, common context. In that special, common context, the state of one data item or transformation is inexorably dependent on the state of the others such that the change of any one requires compensating changes to the others.
For more and deeper background on CSP, see the following references:
Barták, R.: “Constraint Programming: In Pursuit of the Holy Grail,” in Proceedings of the Week of Doctoral Students (WDS99), Part IV, MatFyzPress, Prague (June 1999)555-564; Borning, A.: “The Programming Language Aspects of ThingLab, A Constraint-Oriented Simulation Laboratory,” in ACM Transactions on Programming Languages and Systems, 3(4) (1981) 252-387; Apt, Krzysztof: Principles of Constraint Programming, Cambridge University Press, Cambridge, UK (2003); and Schulte, Christian and Stuckey, Peter J.: Efficient Constraint Propagation Engines, ACM Transactions on Programming Languages and Systems, Vol. 31, No. 1, (2009).
CSP, on the other hand, is the process of finding a solution (i.e., a vector of values) for a set of variables that satisfy a set of constraints. It is typically focused on and characterized by computational models that use largely global constraints (dynamically) to guide the execution of a program searching a very large search space for potential solutions to a problem (e.g., finding DNA sub-segments that may be part of a single longer segment based on common sub-segments patterns). Any specific relationship among specific items of data or specific transformations on that data in CSP is purely an indirect consequence of the overall algorithm and global problem constraints. There is no machinery for direct, explicit constraint-based connections or couplings between specific data items, constraints on those specific data items or specific transformations on those specific data items. The idea of CSP is that the constraints can (possibly) reduce the search of an infeasibly large search space to a feasible size by determining that large portions of that space do not contain or are unlikely to contain the solution based on some macro-properties (i.e., global properties) of that large subspace. CSP is mostly focused on constraint satisfaction problems that are best characterized as a “mathematically oriented process akin to solving equations” where the “equations” are the constraints. The problems are mostly combinatorial in nature and the approaches are mostly methods of searching some large solution space for an answer meeting the set of constraints. The constraints are often propagated over the data description as a mechanism of guiding the execution of the search. Typical example problems are:
Simulations of real-world systems, Finding DNA sequences given a large number of overlapping sub-sequences, Determining protein structures, Graphic layout solutions (e.g., projecting a complex network onto a two dimensional surface in a way that makes it easy to understand), Configuring or designing networks such that they meet some set of constraints, Scheduling problems (i.e., scheduling events given a set of restrictions), and Planning problems (akin to scheduling problems).
In contrast to this invention, compensating effects are not directly triggered by remote refinement actions in CSP. In CSP, the problem representation generally comprises two distinct languages, the language that expresses the constraints and the language that defines the data. In the CSP world, the constraint aspect of the problem is formulated as mathematical forms (e.g., logical or equational forms) and that is the conventional way in which most constraint truths are expressed. The form or structure of the data does not imply aspects of the underlying constraint truths. Certainly, the data may have inherent properties that are used but this does not provide that same kind of explicit, operational coupling and connection among individual data items and individual transformations that is manifest in this invention.
In summary, the broad structure of and approach to CSP problems is quite different from that of automatic program generation problems in general and from the constraint-based automatic program generation method using this invention in particular.
Previous Work by This Author
Other automatic program generation solutions also are quite different in structure and mechanism. In previous work by this author (Ted J. Biggerstaff, “A New Architecture for Transformation-Based Generators,” IEEE Transactions on Software Engineering, Vol. 20, No. 12, December 2004), transformations were related to data items through property structures associated with said data items, however, the transformations in said work were triggered by simple state information and they did not manifest a bidirectional, operational coupling that would effect the compensating changes necessitated by remote coupling as defined in this invention.
Aspect Oriented Programming
Aspect Oriented Programming (AOP) is another superficially similar but fundamentally different generation technique. (See Tzilla Elrad, Robert E. Filman, Atef Bader, (Eds.), “Special Issue on Aspect-Oriented Programming,” Communications of the ACM, vol. 44, no. 10, pp. 28-97, 2001.) AOP seeks to separately specify aspects of the target program in a GPL level language and then as a separate process, weave those separate aspects into a design that is more computationally optimal (but a design that is by necessity less modular). For example, one might specify the essence of a computation separately from a cache-based optimization for that computation. AOP is an optimization oriented approach that does not use the mechanisms of this invention to deal with non-localized constraints and to the best of the authors knowledge, AOP does not deal with non-localized constraints at all. Even if by some stretch of logic, AOP might be said to implicitly handle non-localized constraints, it is certainly not via the machinery used in this invention.
Another difference is that AOP is working largely in the GPL domain and not the problem domain or even in the programming process domain (i.e., the domain that specifies the process of formulating abstract design entities and step by step refining them into concrete program entities). That is to say, the domain abstractions that this invention deals with are not a part of an AOP specification as explicit entities. For example, an implementation free specification of a computation is perforce not in the GPL domain by the very virtue of the fact that it is an implementation independent specification of a computation.
Further, the domain specific entities and relationships used in this invention (e.g., an abstract design pattern) would be difficult to express in an AOP specification because of the AOP bias toward concrete, GPL representations, which impedes the objective of this invention to create provisional, partial design edifices and defer making concrete GPL-level decisions until the broad architectural frameworks have been derived.
Additionally, the process of leveraging domain knowledge to formulate provisional but still incomplete designs in order to decompose the generation process into a series of steps that solve smaller, simpler problems in the course of achieving an overall generation goal, falls outside of the context of AOP. In the context of this invention, determining that instruction level parallelism is possible and desirable is easily made at an early stage of the processing when the computation specification is in a highly domain specific (and abstract) form and when those domain specific forms can suggest the possibility of instruction level parallelism and some of the abstract design details of it. However, the low level details needed to formulate the actual parallel instructions (e.g., an existing and populated coefficient array) have not been developed at this early stage. Later, when those needed low level details do become available, the early preparation work informs the later stages about some of the objectives, entities and constraints that will have to be incorporated into the process that derives the actual low level parallel instructions.
Another key difference is that AOP has no machinery for non-localized constraints connecting and mediating the changes to program entities and to programming process entities separated across the physical program, nor any concept of those same entities connected across generation times (e.g., connecting entities in a design stage with entities in a GPL stage).
OBJECTS AND ADVANTAGES
The objects of this invention are:
Non-localized constraints are signaled and partly established by specialization of related but separated program objects (i.e., operators and/or operands).
Transformations are part of the underlying machinery that derives in a step by step manner the intended computer application implementation from an implementation free specification of the intended computation.
The Intermediate Language (IL) is the abstraction mechanism used to represent elements of the final implementation that have not yet been fully determined or fleshed out by the early phases of the generation process. That is, elements of the IL are temporary stand-ins for the concrete code that cannot be written at the time the IL is generated because the information required to express the IL as concrete code is not yet available. For example, code organizing decisions may not yet have been made, contextual details that determine the details of the concrete code may not yet have been generated, variations in the concrete code details implied by desired design features (e.g., parallel, thread-based decomposition of the computation or re-expression of expressions to exploit instruction level parallelism) may not yet have been introduced into the evolving computation, and other similar impediments.
Method Transformations are the form used to express the Intermediate Language. These forms are method-like operations specific to design objects (e.g., specific to image data structures or neighborhoods within image). When design objects are specialized, their associated IL operations may be specialized by a Higher Order Transformation (HOT) to reflect the introduction of design features in the intended implementation. HOTs are transformations that transform other transformations (where those other transformations are sometimes called first order transformations or low order transformations).
Constraint Coupled programming design objects that are related but separated within the target program Abstract Syntax Tree (AST) such that their refinement into program code is inextricably linked, thereby allowing for changes to one program object to be automatically compensated for by related changes to the others in order to maintain their overall constraint invariant relationship. Using a quantum mechanics metaphor, this concept might be thought of as an analog of “action at a distance” where, for example, measuring the spin of one of a pair of coupled but separated quantum particles instantaneously and inexorably determines the spin of the other particle.
Abstract Design Patterns (ADPs) are a method of partially and provisionally specifying the design of a function or part of a program without fully and finally expressing it in the low level detail of a general programming language (GPL) form. ADPs allow many design features that are to be part of the eventual implementation but not fundamental to the target computation's definition (e.g., those that depend on the structure of the execution platform, or more concretely, those that exploit multicore or vector instructions) to be deferred and separately specified by the application programmer on a platform by platform basis. Then later and as a separate generation process, these design features can be used to customize the target computation for the intended platform.
The advantages are:
No application reprogramming is required to change from one execution platform to a different execution platform. The implementation free specification of the computation does not need to be changed in order to move to a new execution platform and, more importantly, to take full advantage of all optimization opportunities (even new ones) provided by that new platform. Only the execution platform specification needs to be changed by the application programmer, which is a matter of changing a few domain specific descriptors. Of course, the program generation system needs to be updated to accommodate any new execution platforms that become available. While different in kind, this is analogous to providing a new compiler for a new machine. Once the new generation system is provided, the application programmer does not have to reprogram his application to take advantage of new execution platforms.
Execution platform advantages (i.e., high capability facilities) are automatically exploited without explicitly programming or reprogramming of those high capability facilities into the fabric of application programs. The generation program using this invention automatically incorporates these high capability facilities into the fabric of the application program. For example, multicore, instruction level parallelism and GPU subsystems among others may be exploited without effort on the application programmer's part. This invention is analogous to but a large improvement over high level language (i.e., GPL) compilers that allowed a GPL to paper over and hide the local variabilities in instruction sets of a wide variety of computers. GPL compilers worked well until the variety among computers began to be non-locally spread across the full architecture of the machine and compilers that could deal reasonably effectively with mostly local variability of instructions were unable to effect the global and sweeping alterations of form that are required to exploit broad architectural variations in these newer execution platforms. Dealing with architecture-wide variability is a qualitatively different kind of problem. Up to now, it has required a human programmer to reformulate the broad application architecture to accommodate and exploit the new architecture-wide variations in new machines. And just as applications that were written in native instruction level code became captives of specific machines, applications written to exploit broad architectural structures of specific machines once again became captives to those specific machines. GPLs could no longer hide such wide machine to machine variations. This invention introduces methods and machinery that hide the broad architectural variations among machines by allowing the application programmer to write implementation free applications (meaning there is no vestige of the machine architecture in the application specification) and then allowing this invention (in conjunction with the machinery claimed in patent application Ser. No. 12/363,738) to incorporate the global structures required to exploit those broad architectural features.
Coherent refinement of related but separated objects including operators, operands and even higher order objects (e.g., generative transformations) eliminates the combinatorially many cases that without it would have to be checked at one object of a related set of objects to determine what transformations had been previously applied to any related objects. In a similar vein, coherent refinement allows the merging of separated generator contexts (i.e., separated in time and space) so that needed information can be pieced together for use by a refinement at a later time when complete knowledge has been assembled for some generation step (e.g., reformulating loops as expressions of vector instructions). For example, knowledge of loops and their bounds may be available in the context of a domain operator (e.g., a convolution step operator) that defines how to process an input image pixel and its neighboring pixels into a corresponding output image pixel (e.g., each pixel in the neighborhood is multiplied by a convolution specific coefficient and then all of the results summed to produce the output pixel). Later, knowledge of how to compute those problem specific coefficient values to be used in the convolution step is discovered in a different context containing a “call” to a domain specific function known to produce such values (e.g., the W method-transform that is specific to the neighborhood of pixels). Putting these two pieces of knowledge together allows the generator to generate code that will compute the coefficients and store them in an array thereby setting up the preconditions for a design that exploits vector instructions available on the execution platform. Guided by domain knowledge to ensure the coherent coupling of the contexts that contain pieces of the data needed, setting up these preconditions is accomplished purposefully and without the large amount of problem space search that would be required to discover these relationships without the domain knowledge to establish this coherence across space and time contexts.
Non-interference of separate optimization goals allows the most sweeping goals to be achieved first and the less sweeping goals deferred until later. For example, the most profitable optimization goals or the goals that have largest affect on the overall target program design (e.g., designing for multicore parallelism) can be accomplished first and the less profitable goals or goals with more localized affects (e.g., Instruction Level Parallelism or ILP) can be accomplished later within the context of the architecture established by the more sweeping goals. This allows the most sweeping goals to establish the broadest form of the target program's architecture and the less sweeping goals to be achieved within the context of that broad architecture and without interference between the two goal sets.
Efficient Optimization Opportunity Detection is a hallmark of this invention. Rather than defaulting to strategy that looks for a broad list of possible optimization opportunities via an exhaustive search of the lowest level representation of the program (i.e., a GPL representation), the invention uses of domain specific knowledge embedded in higher level, pre-GPL representations to focus the search narrowly in a radar-like manner on only those likely candidate targets of optimization (e.g., neighborhood loops in convolution operations are known to be likely targets of ILP optimization). Thus, this invention uses domain knowledge to minimize the amount of search required to find and effect optimization opportunities. (See the example from the Coherent Refinement advantage.)
Ability to exploit the most useful domain specific knowledge at various times of the generation process by decomposing the optimization into subtasks allows each of these subtasks to best exploit the knowledge available to the generator at different times in the generation process. In an earlier example, one locale provided knowledge of loops needed to set up an array of coefficients needed by ILP instructions and a separate locale provided the specifics of how to calculate said coefficients.
Abstract Design Patterns allow deferral of detail design decisions until it is appropriate to effect them. This is important because reformulating the broad architectural structure of an application program is often a multi-stage process where the later stages cannot accomplish their part to the overall task until earlier stages have evolved the application design to a sufficiently concrete form wherein the later, very concrete structures can be formed and integrated. For example, design decisions that depend on other design details that are only available late in the design process or that do not have a sweeping affect on the details of the overall design will be deferred until the broad architecture of the target program is established. ADPs accomplish this by defining a common vocabulary (e.g., common generator variables), a common programming process context for the design, a set of constraints (e.g., constraints that will eventually evolve into explicit GPL loop structures) and a set of stand-in operations for design details to be determined later, where said stand-in operations are called the Intermediate Language (IL). By these mechanisms, the ADP establishes the descriptive intent of the eventual GPL code (including context, structures and relationships) without expressing the design in a fully determined GPL (i.e., prescriptive) form. For example, the constraints of an ADP do not provide complete prescriptive details of certain elements of the design (e.g., loop structures) but do provide goals and assertions that guide and constrain the eventual GPL forms that will be generated for those elements.
BRIEF SUMMARY OF INVENTION
This invention is a method and a system for expressing dependencies among separated parts of an intended application implementation that are being generated from an implementation free specification of the intended computation. It is also a method and a system for expressing dependencies among separated refinement steps that must work in concert to produce the intended application implementation. Moreover, the invention is a method and a system for using non-local constraints to maintain the constraint-defined relationship among space-separated parts within an implementation and among time-separated generation steps that produce the implementation, where the relationship is maintained even as the implementation goes through its step by evolutionary step changes in its evolution toward its final, GPL implementation form. That is, changes at one of the separated points are automatically compensated for by changes at the other, separated points so that overall consistency is maintained within the implementation generated. Similarly, changes produced by one generation step at one time during the generation are automatically compensated for by changes produced by a later, related generation step at a later generation time. By this invention, program design goals that may require a symphony of globally related operations to accomplish can be accomplished while still retaining the computational relationships required to faithfully fulfill the intent of the overall computation.
DRAWINGS
Drawing Figures
FIG. 1 is a phase by phase timeline of interrelated operations.
FIG. 2 a is an example of the transformation from domain operator to loop.
FIG. 2 b illustrates inlining of domain operators and the operations it triggers.
FIG. 2 c shows the first part of FIG. 2 b operation—inlining of convstep operation.
FIG. 2 d shows inlining of W and the results of triggered code to populate weight array.
FIG. 3 a shows transformation logic for operators coupled by DSL Convolution operation.
FIG. 3 b shows logic that identifies coupled operators.
FIG. 3 c is shows logic that converts coupled map-reduce loop to ILP instructions.
FIG. 4 is an example map-reduce (i.e., neighborhood) loop expressed as ILP instructions.
FIG. 5 a is an example of an Abstract Design Pattern (ADP) object that relates domain objects to programming process objects (e.g., the Intermediate Language).
FIG. 5 b is an example of an Abstract Design Pattern (ADP) object that is specialized for ILP.
KEY REFERENCE NUMERALS IN DRAWINGS
2 a - 01 : Digital image c
2 a - 02 : Neighborhood sp within image c
2 a - 03 : Image loop with domain specific convolution operation in body
2 a - 04 : Transformation to refine CONVOLVE operation into neighborhood loop with coupled, specialized operators forall ILP and += ILP
2 a - 05 : Refined neighborhood loop resulting from transformation
2 b - 01 : Transformation specializing CONVSTEP to ILP friendly form
2 b - 02 : Transformation specializing W to ILP friendly form
2 b - 03 : Generation of Preroutine to be executed when W is inlined
2 b - 04 : Operation to create array for W's weights
2 b - 05 : Operation to bind W's weight array to generator variable ?Dsarray
2 b - 06 : Operation to create and populate weight array
2 b - 07 : Left hand side (LHS) of transform to specialize CONVSTEP definition
2 b - 08 : Right hand side (RHS) of transform to specialize CONVSTEP definition
2 b - 09 : Left hand side (LHS) of transform to specialize W transform
2 b - 10 : Right hand side (RHS) of transform to specialize W transform
2 b - 11 : Preroutine of W of sp ILP
2 c - 01 : Digital image c
2 c - 02 : Neighborhood sp within image c
2 c - 03 : Neighborhood loop from 2 a - 05
2 c - 04 : Transformation that inlines CONVSTEP's definition
2 c - 05 : Neighborhood loop resulting from transformation 2 c - 04
2 d - 01 : Digital image c
2 d - 02 : Weight array from 2 b - 04
2 d - 03 : Image loop with embedded convolution loop from 2 c - 05
2 d - 04 : Transformation to recursively inline W's definition and trigger W's preroutine created by 2 b - 03 , which will populate weight array with values
2 d - 05 : Fully inlined image and neighborhood loops
4 - 01 : Digital image c
4 - 02 : Results of FIGS. 3 a - b - c transformations to fulfill non-local constraints built into ILP operators
4 - 03 : Convolution weight array needed for 4 - 02
5 a - 01 : Abstract Design Pattern for a convolution operation
5 b - 01 : Abstract Design Pattern for a convolution operation
5 a - 02 : Signature of expression to which the ADP applies
5 b - 02 : Signature of expression to which the ADP applies
5 a - 03 : Superclass ADP from which this ADP inherits
5 b - 03 : Superclass ADP from which this ADP inherits
5 a - 04 : Context mapping from ADP role terms (e.g., image) to generator's design variables (e.g., ?a)
5 b - 04 : Context mapping from ADP role terms (e.g., image) to generator's design variables (e.g., ?a)
5 a - 05 : Intermediate Language (i.e., abstract building blocks for generation) specific to this ADP
5 b - 05 : Intermediate Language (i.e., abstract building blocks for generation) specific to this ADP
DETAILED DESCRIPTION
The Problem
Domain Specific Languages (DSLs) have a distinct advantage over GPLs in that a large amount of complex computation can be specified with a small expression of DSL operators and operands. For example, an image convolution operation (see convolution definition below) can be expressed in a small number of symbols, e.g., “(convolve a w)” where a is an image and w defines a matrix of coefficients, where the dimensions of a and w define the extent of the implied iteration loops and where the definition of convolve for each [i,j] pixel of a is a reduction loop (also called a neighborhood loop) producing the output pixel corresponding to the a[i,j] input pixel, e.g., the sum for all p and q of w[p,q]*a[i+p,j+q], where the reduction loop processes some neighborhood of pixels around pixel [i,j].
More generally, an image convolution computes an output image from an input image where each pixel in the output image pixel is a computation of the neighborhood of pixels surrounding the input image pixel that corresponds to the output pixel. A typical neighborhood computation is the sum of all of the products of each pixel in a neighborhood of the current input image pixel times a coefficient specific to the relative position of the pixel within the neighborhood where the neighborhood is centered on the current input image pixel. Convolutions in general allow a wide variety of pixel-coefficient (more generally referred to as the map) operators (e.g., max, min, xor, plus, times, etc.) paired with related loop operators (more generally referred to as the reduction operators) (e.g., sum loop, product loop, min loop, max loop, xor loop, etc.).
The disadvantage of DSLs are that the structure and organization (e.g., nesting) of their naïve or straightforward GPL translations tend to reflect the structure and organization of the DSL expression. Unfortunately, that structure and organization is frequently fundamentally different from the optimal structure and organization that would be required to exploit high performance capabilities of the execution environments that the GPL code will run on. For example, a convolve operation for a single pixel a[i,j] would most generally be defined as a reduction loop of some kind (e.g., a summation loop) within which is nested some reduction-related pixel-coefficient map operation (e.g., coefficient times a pixel value). However, on certain execution platforms, viz. those with Instruction Level Parallelism (ILP), the whole reduction loop and the related pixel-coefficient operation are often expressible as a single machine instruction (e.g., one of Intel's PMADD instructions) or at worst, a handful of machine instructions suitably combined to express the full extent of the reduction loop. Unfortunately, direct generation of ILP instructions raises the possibility of conflicting optimization goals within a program generation system. This is most clearly seen with program generation systems that are able to achieve high performance improvement by using strategies that typically require an intelligent human programmer to put into practice. An instance of such a generation system is that of patent application Ser. No. 12/363,738 (Endnote 1) and its reduction to practice implementation, DSLGen. DSLGen introduces performance enhancing broad scale architectural features to the target program before generating low level details that might hide or conflict with those broad scale features. That is, DSLGen is attempting to achieve the large grain, high profit performance improvements before focusing on the small grain, lower profit performance improvements. Specifically, DSLGen uses abstracted partitions to divide a computation into chunks that can be computed in parallel (e.g., on multicore computers) before generating the instruction level details where the potential profit from parallelism is smaller. In the course of designing the broad scale architecture for those large computational chunks, the computational chunks may be woven together to minimize redundant computation (e.g., via the sharing redundant loops) and that the weaving may hide or obscure the opportunities for the instruction level parallelism. This obscuring occurs because the reduction loop operator of the convolution (i.e., the summation loop) may become separated from the pixel-coefficient operation (i.e., the times operation) by intervening code making the detection of the opportunity and the fusion of the reduction loop and pixel-coefficient operation into a single operation more difficult and costly. Additionally, simplification operations on the evolving code may introduce the possibility of a large number of variations to the forms of the reduction loops and their bodies. This increases the difficulty and cost of detection by introducing a combinatorial explosion of cases that need to be checked for, not to mention the explosion of possible case-specific rewrites that arise from combinations of other sets of properties (e.g., execution platform properties).
On the other hand, if the generator chooses to generate the ILP code first (i.e., before attempting to find the broad chunks), then the job of finding the broad chunks that can be computed in parallel becomes extraordinarily difficult and costly. The generator is looking for broad scale chunks among a large number of low level details, details at the machine instruction level. The compounded structure and clear outlines of the broad scale chunks are easily camouflaged by the jungle of ILP details. This is why highly general tools for parallelizing existing GPL code have had very modest success to date. Algorithms that attempt to recover the broadest chunks of code that can be computed in parallel from the lowest level of GPL details typically end up recovering a number of smallish chunks. Using this strategy in the generator would in effect mean that it is effectively trying to recover the valuable domain specific knowledge (e.g., the fact that the reduction loop taken together with the pixel-coefficient operation is conceptually a single concept, i.e., a convolution) in order to identify the whole structure as a broad chunk that represents a opportunity for parallel expression. This is exactly the domain knowledge in the DSL convolution expression that was lost when the convolution was translated into a series of GPL or machine level instructions. This domain specific knowledge provides a large amount leverage in the job of establishing a computation's large scale architectural features, leverage that turns a really difficult and costly problem into a tractable one.
Beyond the general argument that, in the context of automatic generation, broad design followed by low level design produces arguably the best overall performance improvement, consider that during its early design stages where the broad features of the computation are being established, DSLGen purposefully creates the necessary preconditions for successful ILP optimization of the reduction loop (e.g., preconditions that are tailored to accommodate Intel's PMADD instruction). That is, it reorganizes the low level details so as to hand this optimization opportunity to the later optimization phases on a silver platter. Therefore, it is logical that it should also make the set up of this silver platter easy to recognize by those later stages without a huge amount of complex analysis. And in fact, DSLGen does exactly that by the machinery of this invention. Specializing the summation and pixel-coefficient operator types not only couples them for the purpose of re-forming them into ILP forms, it also makes them stand out as signal flags to the recognizer so that a minimal amount of search is required to trigger the ILP optimization later in the generation process. By contrast, a generalized optimizer working on GPL would likely be unable to create the preconditions necessary for casting the loops into IPL form and therefore, would likely miss this opportunity for parallelization of the neighborhood loop.
Broadly speaking, the DSLGen generation philosophy is that the best overall performance improvement is achieved by first establishing the broad scale design features of the target program that will likely provide the biggest chunks of performance improvement (e.g., data decomposition to accommodate thread-based parallelism) and by later dealing with the smaller chunks that are likely to yield lesser performance improvement (e.g., ILP reformulation of loops). In a recursive sense, the ILP optimization process itself has its own broad and narrow design stages separated in generation time:
the early broad design activity recognizes the opportunity for ILP optimization of a convolution's neighborhood loop and sets up the preconditions for its success (and by setting up the preconditions, maximizes the ILP parallelization opportunities), and the later design activity reformulates the loop into ILP instructions.
However, by the time the generator gets to this second stage, the domain specific operators have been converted into (reduction) loops distinct from the individual pixel-coefficient (map/accumulate) computations and these domain related parts are separated within the evolving code. How does the generator retain the domain relationship (i.e., non-local constraints) between the separated but related parts (e.g., reduction loop operation and the pixel-coefficient map/accumulate operation of the convolution's definition) so that when the time comes, the generator will be able to recognize that even though they are separated from each other, they are domain-specifically related and are ideally set up for ILP representation? What is needed is a method by which to couple the two parts (e.g., the reduction loop and map/accumulate operators) such that their transformation into ILP form makes the proper and coordinated transformations from their individual manifestations to their re-combined manifestations (i.e., an expression of vector instructions) in the target program. Further, the knowledge that together they represent the domain concept of a convolution neighborhood loop will provide knowledge to the generator that the pre-ILP context was previously and purposely set up to make the conversion to the ILP form straightforward.
The Solution
Rather than take a passive approach to exploiting ILP opportunities as most GPL oriented optimization programs do, DSLGen takes an active role by manipulating the structure of the target program to create specific opportunities to exploit ILP facilities provided by the execution platform. It has a significant advantage in this task in that it has the leverage provided by domain specific knowledge. In the example used to illustrate this, DSLGen knows about convolution operations and in particular, that the neighborhood loops of a convolution are often exactly the kind of computation that lends itself to ILP. Further, it knows about the provisional structure of convolution computations and that knowledge guides the process whereby the pre-conditions are established that will lend themselves to ILP formulations. This process exploits the domain specific knowledge that will guide the reformulation of the method w of a neighborhood to use an array of values as its coefficients thereby establishing preconditions for the neighborhood loop in which w occurs to be reformulated as one or more ILP instructions (e.g., one of the PMADD family of instructions).
FIG. 1 is an overview of the overall process showing what operations are occurring for each relevant generator phase in the furtherance of the ILP design feature encapsulation. First, the Partitioning and Loop Localization phase begins the process by formulating the convolution implied loops over the image and convolution implied loops over the neighborhood of each image pixel. This is the point at which, if the execution platform specification allows ILP, the neighborhood loop is generated using coupled operators (e.g., forall ILP and += ILP ) which signals the opportunity for re-expressing this loop as an ILP loop. Most importantly, these coupled operator instances know explicitly about each other and retain the information that together they are an expression of a convolution neighborhood loop.
This first step is illustrated in the example of FIG. 2 a , which shows the relationship among:
1) The before (Ref. 2 a - 03 ) and after (Ref. 2 a - 05 ) convolution code forms (See a note on the expression formats used in these figures in the next paragraph), 2) An image c ( 2 a - 01 ), which is to be convolved, and 3) A neighborhood sp ( 2 a - 02 ), which will supply the coefficients (or weights) of the convolution operation.
These examples are expressed in a list-oriented prefix form where the operator or function name is represented as the first element of a list. Thus, an operator that is normally shown as an infix operator (e.g., “x+y”) would have the operator shown as the first element of the list (e.g., “(+x y)) followed by the arguments separated by spaces (rather than commas). In this example, the operators include assignment (i.e., “=”), incremental assignment (i.e., “+=”), loop operators (i.e., “forall” and “forall ILP ”), array indexing (i.e., “(aref c idx13 idx14)”) and expressions of domain specific operators (e.g., “CONVOLVE” and “CONVSTEP”).
Before the formulation of the neighborhood loop, the as-yet-to-be-translated neighborhood loop is represented by the CONVOLVE operator applied to the pixel of c, i.e., (aref c idx13 idx14) and a relative offset from the center of the neighborhood, i.e., (aref sp p15 q16). The aref operation is the internal form that represents an indexing operation (e.g., its form in the C language would be c [idx13] [idx14]). Idx13 and Idx14 are the provisional target program index variables for the loops that traverse the image c. They may be changed to other variable names later in the generation process because the generator might decide to exploit some loop sharing, hence the “provisional” designation for these variables. Finally, the abstract design object sp is treated as if it were simply a 2D matrix using the indexing operation (aref sp p15 q16), where p15 and q16 are the provisional target program variables that index over the neighborhood sp. In this case, “aref” behaves as if it were an object-oriented method of the sp design object. The neighborhood sp is shown overlaying a portion of the image c.
The second group of related operations shown in FIG. 1 happen during the inlining phase of DSLGen. This is where the Intermediate Language (IL) definitions are inlined. The IL represents the set of convolution design pattern abstractions that stand in for elements and operations of the target program language (e.g., C) that have not yet been determined. For example, the DSL definitions for design pattern abstractions like CONVSTEP and (W sp . . . ) will be substituted into the abstract program during this phase. Up to this point, the IL definitions may have been transformed (i.e., specialized) to encapsulate (or incorporate) some of the design features of the execution platform or some design features desired by the application programmer. This design feature encapsulation in the IL is a key mechanism of evolving the implementation independent specification into an execution platform specific implementation that exploits high capability features of the execution platform (e.g., parallelism). In fact, even during the inlining phase itself, encapsulations continue to occur and ILP is a prime example. The inlining of the CONVSTEP definition will trigger the encapsulation of the ILP design feature in the IL associated with the convolution step and the neighborhood object.
In DSLGen, the inlining (i.e., substitution) of IL definitions is delayed until later in the generation process because DSLGen may need to transform these definitions to encapsulate (i.e., to incorporate) other design features required by the execution platform or desired by the user. These encapsulations may redefine the IL definitions. For example, the computation may need to be partitioned to take advantage of multicore parallelism and that partitioning is likely to decompose the convolution loops into a number of more fine grained loops each of which handles only a part of the overall image. Because the ILP formulation process requires knowledge that is not available or not settled until after all encapsulations and substitution of these definitions are complete, the process that is setting up the preconditions for ILP needs to leave signal flags for the later generation phases to indicate where the ILP opportunity has been set up and what are the related but separated parts that will take part in the ILP re-expression. The multi-stage characteristic of ILP generation is a key motivation for this invention. These signal flags (i.e., in this example the coupled operators) not only identify the ILP opportunities but they also provide coupling and constraint relationships that will be used by the later phases to coordinate the re-expression of conventional loops as ILP instructions. For example, if an ILP instruction accomplishes all or part of the loop's iteration job, the loop expression must be reduced or eliminated accordingly.
FIG. 2 b is an overview that illustrates the ILP encapsulation process that occurs during the inlining phase of the generator. This is a process that illustrates another aspect of coupling, viz. the coupling of two interrelated generative processes that execute at different times and locations but cooperate to achieve the overall aim of setting up the neighborhood loop to be expressed via ILP instructions. The first process in FIG. 2 b is the specialization of CONVSTEP and W for ILP expression (i.e., steps 2 b - 01 and 2 b - 02 ). The specialization of CONVSTEP ( 2 b - 01 ), which produces the new transformational definition of W of sp ILP (comprising 2 b - 09 , 2 b - 02 and 2 b - 10 ) and its preroutine ( 2 b - 11 ), is an example of a transformation generator chain. The specialization of W for ILP is an example of a dynamically generated transformation. This process is triggered by an ILP design feature in the execution platform specification. In the course of specializing these two definitions for ILP, this process also generates a preroutine (i.e., item 2 b -II) (See next paragraph for further information on preroutines) (i.e., via step 2 b - 03 ) for a new w of sp ILP , where sp ILP is a specialization of sp that is specific to ILP formulations. Later, when W of sp ILP is being inlined, just after a successful match of the left hand side (lhs) pattern (i.e., item 2 b - 09 ) of w of sp ILP , this preroutine will execute to create and populate an array (e.g., dsarray9) that will hold the weight values of sp. (The lhs pattern of a transformation is essentially a generalization of a conventional calling sequence and for the purposes of this description can be conveniently thought of in this way.) The preroutine also creates a binding for the pattern variable ?dsarray that is needed in the right hand side (rhs) of the definition. Now, let us examine this process in more detail.
DSLGen (the preferred embodiment) provides a facility for user written Preroutines that will be run after a successful pattern match of the left hand side of a transformation. These Preroutines perform operations that are not well adapted to pattern matching (e.g., data management operations). The Preroutines can succeed or fail. If they fail, the overall transformation with which they are associated fails. If they succeed, the overall transformation is allowed to succeed and optionally, the preroutine may also extend the binding list to provide additional bindings for use in instantiating the right hand side of the transformation.
Step 2 b - 01 During the inlining of CONVSTEP, there is a choice between a default CONVSTEP definition or a customized CONVSTEP definition. In the example shown, the customized definition is triggered because the execution platform specification includes an ILP design feature (e.g., a feature called “SSE” that indicates the availability of Intel's SSE instruction set). In the course of developing the customized definition, the neighborhood (e.g., sp) will be specialized to an ILP specific neighborhood object (e.g., sp ILP ), which will cause the use of IL definitions that are specialized to the ILP design feature. Without the ILP design feature, step 01 would not execute, the default definition of CONVSTEP would be inlined instead and no further processing would be triggered. However, with the ILP design feature, in addition to Step 2 b - 01 , Steps 2 b - 02 and 2 b - 03 are also triggered by CONVSTEP's inlining.
Step 2 b - 02 : W of sp is specialized to operate on sp ILP and is also redefined to fetch its weight value from a specific pre-computed array (e.g., dsarray9) that will be created by W's preroutine where the pre-computed array will be bound to the ?dsarray pattern variable by the preroutine.
Step 2 b - 03 : The final step in the inlining of CONVSTEP will create a preroutine for W of sp ILP . Later in the processing when W of sp ILP is inlined, Steps 2 b - 04 through 2 b - 06 will be executed. Those steps accomplish the following tasks.
When the preroutine is finally invoked later, it performs steps 2 b - 04 , 2 b - 05 and 2 b - 06 .
Step 2 b - 04 : The preroutine creates an array (e.g., dsarray9) to hold the values of the weights.
Step 2 b - 05 : The preroutine binds the newly created array to the pattern variable ?dsarray so that when the definition of W of sp ILP is inlined it will become something like “(aref dsarray9 p15 p16)” where the example variables dsarray9, p15 and p16 will be variables in the target program being generated.
Step 2 b - 06 : The preroutine contains skeleton code for populating the array, where that skeleton code was generated by Step 2 b - 03 . The original right hand side (rhs) of w (e.g., “(f ?a ?i ?j ?p ?q)” in item 2 b - 09 ) is incorporated into the skeleton code in instantiated form (e.g., “(f c idx13 idx14 p15 q16)”) where the instantiation values come from matching the signature pattern (i.e., item 5 a - 02 ) of the convolution's abstract design pattern FIG. 5 a . These instantiations arose from the point earlier when the convolve operator expression was originally recognized and translated into the form shown in 2 a - 03 and they have been carried along to this step. After instantiating the skeleton code with all of the bindings (i.e., from the match of item 5 a - 02 ) and including those created in the preroutine (i.e., item 2 b - 11 ) of W (e.g., (?dsarray dsarray9)), the skeleton code will be partially evaluated to produce the initial values for the array. If the evaluation produces constant values, this step will produce a declaration that is the internal form that will eventually be converted to C code such as:
int dsarray9 [3] [3]={{−1−2−1} {0 0 0} {1 2 1}}};
Most often, this array population will happen at generation time, because values can be determined at generation time. But if the results of the partial evaluation cannot be reduced to constants, then the generator will produce a declaration without initial values such as
int dsarray9 [3] [3];
supplemented by preamble code to the neighborhood loop (i.e., the partially reduced form of the precursor code produced by step 2 b - 06 ) and that preamble will produce those values for dsarry9 at execution time. If data dependencies prevent even that (i.e., each coefficient can only be computed just before its use), then the ILP conversion will fail because in this case, the potential parallelism provided by the ILP instructions will be defeated by the incrementalism inherent in the calculation of the data vector. So, the neighborhood loop will not be able to take advantage of ILP instructions. However, this latter case is typically an anomalous case and is infrequent in normal computational environments.
FIG. 2 c illustrates an example of what is happening to the internal program representation as CONVSTEP is inlined. Behind the scenes, Steps 2 b - 01 through 2 b - 03 are occurring during this transformation.
Similarly, FIG. 2 d illustrates an example of what is happening to the internal program representation as W is being inlined at a later time in the generator's processing. Similarly, Steps 2 b - 04 through 2 b - 06 are occurring during this transformation.
The Loop Simplification phase from FIG. 1 occurs after all inlining is complete. Among the transformations triggered during this phase is the transformation that re-expresses the neighborhood loop with the coupled operators as an expression of ILP instructions.
The details of this process are defined in FIGS. 3 a - c . FIG. 3 a deals with the possibility that program structures have been added before or after the += ILP operation. It handles one map operation plus one step of the reduction process and succeeds if there is no preblock or postblock of code, or if there is a preblock that has no data flows into the += ILP expression. The main logic for reformulating the coupled pair is handled by FIGS. 3 b and 3 c . ILPLoop of FIG. 3 b handles identifying the coupled operators, deconstructing the neighborhood loop into its parts and then calling RewriteLoopAslLPExpr ( FIG. 3 c ) to construct the actual ILP form of the loop or, failing that, to return the existing loop unchanged.
FIG. 4 is the ILP version of the neighborhood loop that is formed if the re-expression is successful. The unpackadd (where, unpackadd is a convenient pseudo-SSE instruction that is implemented via a short series of machine instructions), padd and pmadd abstractions are modest generalizations of the actual SSE instructions. In practice, these generalizations are defined as C #define macros that reduce these generalizations to the explicit SSE instructions while dealing with low level issues such as register loading and register assignment for communication between the individual SSE instructions.
Several question remains unanswered. How did the various operations know how to choose the objects and IL that they were manipulating? How can the generator represent elements of the target program that cannot yet be determined because information that they depend on has not been determined? And how does the evolving design pattern progress toward a concrete expression of the design and keep track of the evolving parts thereof? The example driven figures elided these problems by illustrating the operations via somewhat specific examples, which make the general operations easy to understand because the specificity allows human (domain specific) intuition to make the connections. The technical answer to these questions is that the generator uses an Abstract Design Pattern object (illustrated in 5 a - b ) to provide the machinery necessary to solve these various problems.
The ADP provides mechanisms to:
Define and name an Abstract Design Pattern (Lines 5 a - 01 and 5 b - 01 ) Recognize the expression in the AST to which the ADP applies (Items 5 a - 02 and 5 b - 02 ). Inherit parts from more general ADP definitions (Lines 5 a - 03 and 5 b - 03 ). Connect ADP roles to the pattern variables that will be bound to concrete AST expressions (Definitions at 5 a - 04 and 5 b - 04 ). Define the Intermediate Language used to stand-in for elements of the target program that are not yet fully determined (Definitions at 5 a - 05 and 5 b - 05 ).
The ADP defines meta-information that will be used by the transformations that evolve the code for the target program. The exact structure of portions of the final code (e.g., various loops and their context) is implicit and only fully determinable after the full evolution of the ADP into code. The implicit structures may include, for example, sets of loops implied by domain specific operators (e.g., a convolution operation on an image and a neighborhood template of that image), a recursion design based on a domain specific tree structure, a design framework exploiting domain specific algorithms that may be well tailored to a specific design feature (e.g., a Red-Black tree), a synchronization based pattern for parallel computation (e.g., shared queues or a Single Program Multiple Data design) and variations of those sorts (e.g., loops partitioned into separate thread routines).
The explicit information of an ADP, on the other hand, is represented as explicit data within the ADP. One kind of explicit information (i.e., Items 5 a - 04 and 5 b - 04 ) expresses the meta-relationship between domain specific conceptual roles defined within an ADP and the pattern variables that will be bound to specific instances of expressions playing that role in target program AST. For example, a role might be a “template” and its corresponding pattern variable might be “?s”. Thus, this establishes a common naming convention within the generator's transformations that allows them to share data consistently. Furthermore, the roles allow higher order transformations that are applied to IL definitions to encapsulate design features and those higher order transformations are written in terms of role names. When combined with an ADP context, the high order transforms to perform a generalized operation (e.g., mapping an index variable from one range to another) on variety of specific IL definitions whose concrete variables can vary from ADP context to ADP context. For example, a high order transformation might apply a role-base rule of the form Pindex 0 =>(Pindex 1 −PindexLow 1 ) in the context of the ADP of FIG. 5 a to map the variable ?p to (?p−(−1)), which with simplification would finally become (?p+1). This is exactly what happens when the generator is encapsulating the design feature that requires arrays to be indexed like C language arrays (i.e., from 0 to (n−1)) rather than like the Image Algebra DSL (i.e., from −(n−1) to +(n−1), or as a concrete example, from −1 to +1).
Another kind of explicit information in an ADP is an expression of the IL stand-ins from which the target code will be built. For example, the “row” or “col” stand-in represents how to compute an image row or col from a centering pixel and a template offset pixel in the context of some loop that is only implied by the ADP. Thus, in steps 2 b - 01 , 2 b - 02 and 2 b - 03 , the generator process that is reformulating the CONVSTEP result to be expressed as ILP instructions knows (in a domain specific sense) that the weights need to be put into an array. The ADP context tells the generator process that the weights are computed by a method-like operator “w” applied to a neighborhood template that will be bound to “?s”. This gives it enough information to find the (w sp) definition and a pattern that will recognize the instance of (w sp) in the definition of CONVSTEP (i.e., lhs of step 2 b - 01 ). This allows it to decompose that definition, reformulate the new definition (i.e., rhs of step 2 b - 01 ) and additionally, create the other needed forms for steps 2 b - 02 and 2 b - 03 .
Within the IL definitions, some may not refine into explicit code but rather will have some affect on the final form of the explicit code. For example, the IL definition “(partestx ?s:template)” in item 5 a - 05 a , will refine to a concrete condition that may limit the range of a loop partition, e.g., “idx3==0” and thereby limit the loop to operating only on the pixels on one of the image's edges. That is, if the general loop definition has the GPL C code form:
for (idx3=0; idx3<m-; idx3++)
for (idx4=0; idx4<n; idx4++) {loop body}.
(i.e., the general form consists of two loops traversing the whole image) then adding a condition like “idx3==0” to the loop description will specialize the general form into a specialized “for” loop that traverses only one edge of the image:
for (idx4=0; idx4<n; idx4++) {loop body with 0 substituted for occurrences of idx3 in the body}.
The signature-like expressions in the ADP signature, context and IL fields are shorthand patterns that are formed into operational patterns by the generator. Thus, the form “?a:image” will form a pattern that will match an expression whose type is an image type or subtype thereof and bind the matched expression to the pattern variable “?s”. For example, in the context of FIG. 2 a , a pattern match of the “(CONVOLVE . . . )” expression in of the lhs transformation would result in “?s” being bound to “c”.
In short, the ADP provides indirect connections to all of the piece parts of the evolving program that the program generating transformations will need to work with. The connections are either through
Pattern matching (e.g., matching an ADP pattern to an expression that must be refined into some concrete instance of the design structure), Through indirection (e.g., To form an target program expression involving the neighborhood template of a convolution, the generator uses the binding of “?s” in FIG. 5 a or 5 b ), or Through the method name of an IL expression, which is referred to as a semantically-based connection.
The specific ADP that applies to a domain specific operation is chosen based on the particulars of the operation (e.g., a convolution) plus other specifications of design requirements, application programmer desires and execution platform opportunities (e.g., on an execution platform with ILP the ADP shown as FIG. 5 b might be chosen, subject to approval by the application programmer). | A method and a system for non-locally constraining a plurality of related but separated program entities (e.g., a loop operation and a related accumulation operation within the loop's scope) such that any broad program transformation affecting both will have the machinery to assure that the changes to both entities will preserve the invariant properties of and dependencies among them. For example, if a program transform alters one entity (e.g., re-expresses an accumulation operation as a vector operation incorporating some or all of the loop's iteration) the constraint will provide the machinery to assure a compensating alteration of the other entities (e.g., the loop operation is reduced to reflect the vectorization of the accumulation operation). One realization of this method comprises specialized instances of the related entities that while retaining their roles as program entities (i.e., operators), also contain data and machinery to define the non-local constraint relationship. | 6 |
FIELD OF THE INVENTION
This invention relates to optical waveguides and, more particularly, to a method for producing stacked, parallel, optical waveguides using trench and fill techniques.
BACKGROUND OF THE INVENTION
Many integrated optical devices specify a precisely controlled separation between parallel waveguides. The required separation may be in the neighborhood of a few tenths of a micron, with the separation required to be constant over a distance of several centimeters. Conventional fabrication techniques which orient waveguides in a side-by-side arrangement on the surface of a substrate do not lend themselves to the achievement of the required accuracy and consistency. This is especially the case when waveguides are made from reflowed glasses.
It is known that certain acousto-optic interactions exhibit increased efficiency if the optical waveguides are arranged vertically (i.e. "stacked") as opposed to a side-by-side arrangement. However, in order to achieve such increased efficiency, a multiple-channel, stacked, optical waveguide structure must have planar surfaces to enable proper channel-to-channel interaction. Thus, it is necessary to maintain a planar surface after each fabrication step.
The prior art teaches a variety of techniques for the fabrication of optical waveguides. In U.S. Pat. No. 3,865,646 to Logan et al., a single or double heterostructure is fabricated from gallium arsenide-aluminum gallium arsenide layers. Liquid phase or molecular beam epitaxy are employed, to superimpose layers, one on the other. Two alternative techniques are employed to construct a waveguide layer. In one, an aluminum gallium arsenide layer is epitaxially grown over a mesa to form a two dimensional waveguide. In the second, edges of an active region of an aluminum gallium arsenide double heterostructure are differentially
to provide a defined waveguide.
U.S. Pat. No. 4,070,516 to Kaiser describes a ceramic module body with incorporated glass channels that enable communication with a semiconductor chip mounted on the body. The process employs ceramic green sheets with incorporated glass paste channels.
U.S. Pat. No. 4,715,672 to Duguay et al. describes a planar silicon dioxide waveguide that is bounded by thin polysilicon, high index layers to provide anti-resonant reflecting surfaces.
U.S. Pat. No. 4,929,302 to Valette describes a procedure for producing optical waveguides wherein an additive process produces juxtaposed optical waveguides. A pair of guide structures are separated by a layer whose refractive index is intermediate the two optical waveguides. U.S. Pat. No. 4,933,262 to Beguin describes a method and structure for interconnecting an optical fiber with a planar optical guide.
In U.S. Pat. No. 4,973,119 to Taki, an optical isolator is described that employs a planar waveguide and a magnetic thin film having a magneto-optic effect. The substrate has a refractive index close to the refractive index of the magnetic thin film and the film is magnetized in a direction lying in a plane substantially normal to the direction in which light is propagated through the waveguide.
U.S. Pat. No. 5,013,129 to Harada et al describes an optical frequency converter wherein an embedded waveguide is surrounding by a cladding which fully reflects the fundamental optical frequency being transmitted, but not its harmonics. U.S. Pat. No. 5,018,809 to Shin et al., describes a planar optical waveguide with a self aligning cladding.
U.S. Pat. No. 5,026,135 to Booth describes a method for producing planar optical waveguides with a glassy coating of doped silicon dioxide that provides a low oxygen transmission value --to prevent waveguide deterioration.
Accordingly, it is an object of this invention to provide an improved method for producing stacked optical waveguides.
It is another object of this invention to provide a method for producing vertically stacked optical waveguides which lends itself to the use of differing optical waveguide materials.
It is still another object of this invention to provide an improved method for producing stacked optical waveguides wherein a high degree of positional precision is obtained.
SUMMARY OF THE INVENTION
A method is described for producing stacked optical waveguides in a silicon dioxide substrate and includes the steps of: etching a first trench in the substrate; filling the first trench with a glassy optical transmission media; depositing a layer of silicon dioxide over the filled trench; etching a second trench in the silicon dioxide layer, the second trench aligned with the first trench; and filling the second trench with a glassy optical transmission media.
DESCRIPTION OF THE DRAWINGS
FIGS. 1-13 illustrate the sequential steps of the invention that enable the production of vertically stacked, positionally precise, optical waveguides.
FIG. 14 is an exploded view of an acousto-optic tunable coupler that makes use of the invention.
DETAILED DESCRIPTION OF THE INVENTION
As will be hereinafter apparent, the invention employs a trench-and-fill process to produce planarized, low loss, optical channel waveguides. Using this technique, vertically stacked optical waveguides are fabricated, with the technique allowing highly precise positioning therebetween. The procedure employs reactive-ion etching, chemical wet etching and reflow of deposited glasses, all of which enable precise control of the shape and size of waveguide cross sections. The procedure produces smooth waveguide surfaces that enable the production of ultra-low loss optical waveguides. During the following description, certain waveguide materials will be described as exemplary, e.g., Corning 7059 glass (a trademark of the Corning Company,) Borosilicate glass (BSG), phosphosilicate glass (PSG) and silicon dioxide. Each of these glasses (except 7059 glass) is deposited using a low-pressure chemical vapor deposition (LPCVD) system. The Corning 7059 glass is preferably deposited by an RF sputter process. Clearly, other waveguide materials can be utilized so long as they are subject to the processing procedures to be described hereafter. The substrate on which the to-be-described waveguide structure is constructed is preferably a thermally oxidized silicon wafer on which a 7-10 micron thick silicon dioxide layer is present.
Referring now to FIG. 1, a silicon dioxide, thermal oxidation layer 10 has a photoresist 12 deposited on its surface. Photoresist 12 is photolithographically defined to create a trench opening 14. (The supporting silicon substrate for silicon dioxide layer 10 is not shown. Subsequently, trench opening 14 is etched into silicon dioxide layer 10 using a reactive ion etch procedure.
In FIG. 2, trench 14 is further etched by a wet-etch process to create an enlarged trench area 16. The wet-etch procedure enables the bottom corners of enlarged trench 16 to be rounded and for the bounding surface of trench 16 to be smoothed. In FIG. 3, photoresist 12 has been stripped and a thin layer of borosilicate glass 18 deposited over the surface of silicon dioxide layer 10 and trench 16. Subsequently the wafer is subjected to a reheating step whereby borosilicate glass layer 18 reflows. This process enables the further smoothing of the etched surfaces of trench 16.
In FIG. 4, a layer of phosphosilicate glass 20 is deposited in trench 16 and over the surface borosilicate glass layer 18. The deposition of the phosphosilicate glass layer 20 is preferably carried out using a low-pressure, chemical vapor deposition procedure.
Next, (see FIG. 5) the entire wafer surface is coated with a photoresist 22, which photoresist is then patterned so that it extends only over the extent of the trench area defined by borosilicate glass layer 18. After patterning, the underlying phosphosilicate glass layer 20 is wet etched so that it is somewhat undercut under the remaining photoresist layer 22.
Photoresist layer 22 is now stripped (see FIG. 6) and the wafer subjected to a reheating step whereby phosphosilicate glass layer 20 reflows to fill in the vacant region where photoresist 22 had been removed. As a result, a flat upper surface 21 is produced upon which a layer of silicon dioxide 23 is then deposited using an LPCVD procedure.
Next, as shown in FIG. 7, silicon dioxide layer 23 is coated with a layer of photoresist 24 which is patterned to define a second trench for a Corning 7059 glass optical waveguide. After patterning, silicon dioxide layer 23 is reactive ion etched to create opening 26. Then, the wafer is subjected to a wet-etch which mildly undercuts silicon dioxide layer 23 and acts to smooth the internal surfaces of trench 26.
As shown in FIG. 8, photoresist layer 24 is now stripped and a thin layer of borosilicate glass 28 is deposited and reflowed to further smooth the surfaces of trench 26. Next (in FIG. 9), a layer 30 of 7059 glass is deposited and reflowed. The wafer is then coated (FIG. 10) with a layer of photoresist 32 which is patterned to cover the extent of the trench formed by borosilicate glass layer 28. The underlying 7059 glass layer 30 is wet etched to cause it to be undercut under the remaining portion of the photoresist layer 32.
Photoresist layer 32 is then stripped and the wafer reflowed (FIG. 11) to create a planar upper surface 31 upon which a layer of borosilicate glass 34 is deposited using an LPCVD procedure. FIG. 12 is the same as FIG. 11 except that after the deposition of borosilicate glass layer 34 onto borosilicate layer 28, they merge into a single BSG layer 36. Since the refractive index of borosilicate glass and silicon dioxide are nearly equal, the structure can be represented (optically) as shown in FIG. 13. Waveguides 20 and 30, therefore, essentially reside in a single index medium with the medium acting as a cladding thereabout. Furthermore, since 7059 glass exhibits a higher refractive index than phosphosilicate glass, passive coupling therebetween does not occur under normal circumstances.
Turning now to FIG. 14, an acousto-optic modulator structure is shown that employs the stacked waveguide structure produced by the steps shown in FIGS. 1-13. In FIG. 14, the structure has been exploded so as to show its various components. Silicon dioxide layer 10 has embedded therein stacked waveguides 20 and 30. A borosilicate glass acoustic waveguide layer 40 is superimposed over waveguides 20 and 30 and acts as a modulating element. Zinc oxide pad 42 is disposed on waveguide layer 40 and an interdigitated, conductive transducer 46 resides on zinc oxide pad 42. By applying an appropriate signal to transducer 46 a surface acoustic wave is induced in waveguide 40 which modulates the refractive indices of both waveguide 20 and 30. A grating is thus established which compensates for the mismatch in optical phase velocities within waveguides 20 and 30. As a result, coupling therebetween can be selectively achieved in accordance with a signal induced in waveguide 40.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. | A method is described for producing stacked optical waveguides in a silicon dioxide substrate and includes the steps of: etching a first trench in the substrate; filling the first trench with a glassy optical transmission media; depositing a layer of silicon dioxide over the filled trench; etching a second trench in the silicon dioxide layer, the second trench aligned with the first trench; and filling the second trench with a glassy optical transmission media. | 6 |
[0001] This application claims the benefit of priority of European Patent Application No. 14000636.2, filed Feb. 24, 2014, which is incorporated herein in its entirety by reference.
TECHNICAL FIELD
[0002] The present invention refers to an assembly comprising an engine.
BACKGROUND
[0003] Currently a stationary internal combustion engine is shipped in a container to a distant location. At the destination site the engine is removed from the container and is placed in a building, where the engine may be attached to a generator. The container will be removed from the site and can be used to transport other engines.
[0004] It is also known in the art to assemble a unit comprising an engine, a generator, and supporting devices like a cooler. The unit is placed in a container, so that the container may be used to transport the unit and to house the unit at the destination site.
SUMMARY OF THE INVENTION
[0005] In one aspect, the present disclosure is directed to an assembly comprising an engine and a housing to protect the engine, wherein the housing has a first wall and the first wall further comprises a container.
[0006] In another aspect, the present disclosure is directed to a method setting up an assembly, the method comprising: placing two or more containers to create an empty space surrounded by the containers; placing an engine in the space; and placing a roof on top of the containers to shield the engine.
[0007] In yet another aspect, the present disclosure is directed to a power plant comprising at least two assemblies, each assembly including an engine and a housing to protect the engine, wherein the housing includes a first wall and the first wall further includes a container.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows an assembly.
[0009] FIG. 2 shows an assembly with an engine.
[0010] FIG. 3 shows a power plant comprising two assemblies.
DETAILED DESCRIPTION
[0011] FIG. 1 shows an assembly 1 comprising an engine 2 (not shown in FIG. 1 ) and a housing 3 . The engine 2 may be a stationary combustion engine, particularly a stationary combustion gas-type engine, connected with a generator to produce electric power. The engine 2 and the generator are located inside the housing 3 . The housing 3 has a first wall 4 , a second wall 5 , a third wall 6 , and a fourth wall 7 . The first wall 4 may be parallel to the third wall 6 , and normal to the second wall 5 and the fourth wall 7 . The walls 4 , 5 , 6 , and 7 may form a generally square or rectangular arrangement in which the engine 2 is located. The first wall 4 , second wall 5 , and fourth wall 7 may each consist of two containers, namely, the containers 8 and 9 , 10 and 11 , 15 and 16 , respectively. The containers 9 , 11 , and 16 are placed on top of the containers 8 , 10 , and 15 , respectively. The third wall 6 may consist of three containers, namely the containers 12 , 13 , and 14 , stacked from the bottom to the top, respectively. The containers 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , and 16 may be detachably connected to each other by bolts, screws, locks, turning locks, angle plates, etc. Furthermore, the lower containers 8 , 10 , 12 , 15 may be placed on a foundation, such as a ground plate 17 made of concrete.
[0012] The lower containers 8 , 10 , 12 , and 15 may be placed on leveled bottom plates, which may be positioned on the foundation at the lower corners of the lower containers. Four or more leveled bottom plates may be used per container.
[0013] Between the upper and the lower containers a shield to reduce the transmission of noise, heat, or the both may be installed. This shield may be made of foam material.
[0014] On top of the upper containers 11 and 16 , a roof 18 may be placed, which covers the inner space of the housing 3 formed by the containers 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , and 16 . A chimney 19 may be attached to the housing 3 and connected to the exhaust system of the engine 2 . The chimney 19 may include an exhaust silencer 20 to reduce the operating noise of the assembly 1 .
[0015] The chimney 19 and the exhaust silencer 20 may be attached to a rack 27 , which has the dimensions of an ISO container. An ISO container may have a length of 6.095 m, a width of 2.352 m, and a height of 2.393 m, and could be called a 20-ft container. Alternatively, the ISO container may have a length of 12.032 m, a width of 2.352 m, and a height of 2.393 m, and may be called a 40-ft container. An ISO container could also have a length of 12.032 m, a width of 2.352 m, and a height of 2.698 m.
[0016] The chimney 19 and the exhaust silencer 20 may be at least partially surrounded by the rack 27 .
[0017] The containers 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , and 16 may include doors 21 to allow entrance to the containers and to provide access to the interior of the assembly 1 . Also, the containers 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , and 16 may include windows 22 to allow light to enter the containers.
[0018] The containers 8 , 9 , 12 , 13 , and 14 , forming the first wall 4 and the third wall 6 , may be ISO 20-ft containers. The containers 10 , 11 , 15 , and 16 , forming the second wall 5 and the fourth wall 7 , may be ISO 40-ft containers.
[0019] The container 8 may contain a gas train, and an inter-cooling circuit and its connections.
[0020] The container 9 may contain installations, such as fans, filters, and openings to transport air from the inside of the assembly to the outside.
[0021] The container 10 may be an auxiliary container containing an engine-cooling system and a lube-oil-cooling system. Each of the engine-cooling system and the lube-oil-cooling system may include a heat exchanger. Moreover, an engine-control system and an auxiliary control system may be installed in the container 10 .
[0022] The container 11 may be an exhaust container. An exhaust-heat exchanger and a catalyzer may be inside of the exhaust container 11 .
[0023] The containers 12 , 13 , and 14 may each house an inlet-air system including fans and air filters to supply air to the inner space of the assembly, and the engine in particular.
[0024] The container 15 may contain control units to supply pressurized air to the assembly.
[0025] The container 16 may be a medium-voltage container, housing at least one transformer to provide the assembly 1 with medium-voltage electricity. Furthermore, the container 16 may include a medium-voltage control unit to control the medium-voltage power supply. Medium voltage may be used to power the engine-cooling system and the lube-oil-cooling system.
[0026] FIG. 2 shows an assembly 1 housing an engine 2 and a generator 25 (not labeled in FIG. 2 ). The engine 2 is placed in an area which is defined by the containers 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , and 16 . The engine 2 is directed along the main axis of the housing. The generator 25 is connected to the engine 2 , so that the engine 2 can drive the generator 25 .
[0027] FIG. 3 shows a power plant 26 , which comprises two assemblies 1 . The assemblies 1 are placed next to each other and may be connected by wires, bolts, etc. The main control unit of the power plant 26 may be located in one of the assemblies and connected to the engine of the other assembly 1 .
INDUSTRIAL APPLICABILITY
[0028] In the following the method of setting up the assembly will be described. The assembly may be pre-assembled for transportation at an assembly site. Referring to FIG. 1 , at the assembly site, a gas train and an inter-cooling circuit are pre-installed in the container 8 . Pumps, filters, and control units to transport air from the inside of the assembly to the outside are pre-installed in the container 9 . A heat exchanger and an auxiliary control system may be pre-installed in the container 10 . A catalyzer and an exhaust-heat exchanger may be pre-installed in the container 11 . Devices supplying air to the inner space of the assembly may be pre-installed in the containers 12 , 13 , and 14 . Devices supplying pressured air and associated control units may be pre-installed in the container 15 . Transformers to transform electric power to medium voltage and a medium-voltage control unit may be pre-installed in container 16 .
[0029] Furthermore, the engine, the generator, desk-coolers, pipes, working platforms, and supporting structures may be stored in one or more containers for transportation.
[0030] At a destination site, bottom plates 23 may be placed on a foundation 17 . The foundation 17 may be made of concrete. The bottom plates 23 may be leveled out. The bottom plates 23 may support the containers to keep the containers in horizontal surfaces.
[0031] The bottom containers 8 , 10 , and 15 may be placed on the bottom plates 23 one after another. The containers may be connected by angle plates, which are fixed to the containers by screws. The containers 8 , 10 , and 15 may be arranged in a U-shape, whereby the container 10 and the container 15 respectively may form the legs of the U-shape and the container 8 may be located between the containers 10 and 15 . The container 8 , 10 , and 15 may define three sides of the inner space of the assembly. Shields may be placed on top of the bottom containers 8 , 10 and 15 to insulate noise, heat, or the both. The container 9 , 11 , and 16 are placed on top of the containers 8 , 10 , and 15 , respectively. The top containers 9 , 11 , and 16 may be connected to the bottom containers 8 , 10 , and 15 using twist locks. On top of the containers 11 and 16 a roof may be placed, which spans the inner space of the assembly. Supporting structures and working platforms may be installed in the inner space of the assembly. The engine and the generator may be assembled, connected, and put into the inner space of the assembly.
[0032] The devices and systems located in different containers may be connected with flexible pipes. Electric wires may be set up between the containers to connect electric components in different containers.
[0033] The containers 12 , 13 , and 14 may be placed at the open end of the U-shape to close the open end. Silencers and exhaust pipes may be placed in the containers 12 , 13 , and 14 . | An assembly includes a combustion engine and a housing to protect an engine, wherein the housing has a first wall and the first wall has a container. | 5 |
RELATED APPLICATIONS
The present application contains disclosures found in applicant's earlier in U.S. Pat. No. 3,988,970, U.S. Pat. No. 3,916,770 and U.S. Pat. No. 4,230,300 issued a “square bottom” or “flat bottom” plastic bag and Provisional Patent Application No. 60/365,028 dated Mar. 18, 2002 and Disclosure Documents #492644 dated Apr. 23, 2001 and No. 492645 dated Apr. 23, 2001.
BACKGROUND OF THE INVENTION
The present invention relates to the closure of open top, thin plastic, gussetted bags including a “square bottom” plastic bag, “T” shirt bag and any top opening bag with side gussets formed of thin plastic material.
Plastic gussetted “square bottom” or “flat bottom” bags and regular gussetted bags have supplanted paper bags for use in super markets, retail establishments, and other establishments. These bags utilize the entire space of the plastic bag, stand up right by itself and is self-supporting so that it makes loading and unloading the bag easier.
This heretofore not available new closure will enable such plastic bags to have many uses apparent to the user and the reader of this application.
This bag may be used to hold products in markets, such as, food, deli counter operations, dog food and the like as well as boxed and canned goods. While made of flexible plastic material may be made of sturdy and strong, i.e., heavy wall construction that the filled bag may be conveniently carried. It would also be extremely beneficial to provide means for automated closing the open top after the bag is filled.
It is the object of this present invention to close a “flat bottom” or “square bottom” gussetted bag, after being filled, at the upper edge of the bag while allowing a maximum opening for filling and discharge of the bag.
Another object of this present invention is to provide the bag for use for liquids, solids, semi solids, frozen and defrosted items while maintaining the integrity of the self-standing bottom plastic gussetted sack or bag.
It is another object to provide a “flat bottom” bag with automatic top closure having a carrying handle. The objects as well as other objects and advantages will be obvious from the following disclosures.
SUMMARY OF THE INVENTION
In my prior patents, U.S. Pat. Nos. 3,988,970, 3,916,770 and 4,230,300, I disclosed plastic bags and their manufacture in which a flat bottom has been formed. The “flat” or “square bottom” bag is formed from a tubular sleeve having gussets on each side. A long transverse seal is applied to the bottom of the tube to form a bag. An internal opening mechanism is provided to open and “square off” the bottom Two bottom seals are applied to reinforce the bottom of the bag. Further, square bottom serve to allow the bag to be neatly folded for stacking and shipping. The bags shown in these patents also have side gussetts similarly designed to allow folding and stacking for shipping.
According to the present invention a gussetted bag of the type shown in my earlier patents containing a tubular sleeve having an open top, a closed bottom wall, a front and back faces and a pair of opposing side walls connecting the front and back faces is improved. The side walls are formed with at least one fold creating in the side walls at least one gusset allowing the front and back faces to extend from each other. The gussets are sealed unitarily at the bottom ends of the bottom wall, sealed through and through along their top edges of the the front and back faces inwardly respective from the side wall. Then, as will be seen the “square bottom” bag takes on a triangular lengthwide shape normally biased closed at the top but easily openable for maximum full and discharge of the interior of the bag.
Full details of the present invention are set forth in the following disclosure and shown in the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
In the drawings:
FIG. 1 is a series perspective views showing the construction of a flat bottom tubular bag,
FIG. 2 is perspectal view of a flat bottom bag having the gusset construction of the present invention,
FIG. 3 is a view of the bag invention, on its side, FIG. 2 is a view showing the discharge of goods from the interior thereof.
DESCRIPTION OF THE INVENTION
Seen in FIG. 1 , a typical endless roll plastic of tubular sleeve construction 10 used to form the initial bag 12 to which the invention is applied to. In step A, a portion of the endless tubular sleeve is shaped in accordance with the afore mentioned patents, to which reference can be made as if more fully set forth. The sleeve is cut in Step B, to have a rectangle shape with a transverse cross section having a pair of opposing faces 14 and a pair of side walls 16 . Each side wall 16 is formed with at least a one longitudinal gussets 18 although two pair are preferred. The gussets 18 are folded inwardly and the tubular sleeve flattened by pressing the the opposing faces 14 in together. Then, in Step C, the plastic bag is opened and a “former” or mandrel is moved into the bag 14 so as to “square off” the bottom to make a “flat bottom” 20 . In Step D, bottom seals 22 (one on each side of the bottom) are applied to seal the bottom to the side walls 16 making the “square bottom” rigid. As seen in Step E and F, the bag is then sealed with a seam 24 from side wall to side wall at the bottom with a heat sealing mechanism making the “T” shirt bag leaving the top open ended as at 26 bag.
Turning to FIGS. 2 and 3 , the present invention provides the top edge 26 with a closure seal 46 applied to limit of the length of gusset sides 18 . The reduced gussets sides 18 are made as small as as possible without interfering with the required size of the bag and integrity of the “square bottom” or “flat bottom” 20 . After the gusset sealing is completed all the gusset faces are pressed together and sealed at the top end of the bag with at least one or two band seals 30 including longitudinal seal 48 sealing the pressed gusset faces completely through the film or sheet of plastic.
The top edge 26 of each face may be reinforced with stay 32 of bendable material, such as a corset stay so the bag automatically closes. Also a band 34 integral with the front and rear faces 14 to extend upward longitudinal seal extends from the gussets upward therefrom an opening 36 is fashioned in the band 34 establishing a handle 38 . Below the handle, along the top of the bag itself, a zipper or other closure device 46 may be placed, so that the contents of the bag can be locked and held for shipment.
The number of seals 30 on each side gusset 18 can be selected as desired along with the longitudinal seal 48 . At least one diagonal seal 40 is made at the bottom end of the longitudinal seal 48 on each side of the bag. These diagonal seals 40 made at the end of the longitudinal seal 48 reinforce the longitudinal seal and enable the easy flow of goods out of the bag. (See FIG. 3 )
The block seals 30 are made near the top of the bag to insure that the bag is not torn when filling or emptying out. These block seals also allow the user a place or location to grasp the bag at time of opening, closing the bag and discharging the contents at time of unloading bags. Block seals are applied simultaneously when the long longitudinal seal and diagonal seals are made through all the side gussets. As a matter of fact, all foregoing seals ( 30 , 40 , 48 ) can be made at one time. Once the gusset seals, block seals, longitudual and diagonal seals are in place, the band and a zipper closure with cut-out handle maybe formed to the upper portion of the bag separately by sealing a portion of the flap of the zipper closure to the front and back of the new construction sealed bag.
If made separately, the entire upper portion of the bag containing the cut-out handle and zipper closure is heat sealed to the upper portion of lower bag. The additional block seal 50 is to prevent the zipper from opening past the gussetted sealed upper portions of the bag itself.
Further a small slit 42 is made in the bag at a location below the top edge closure. This will enable the easy flow of material in and out of the bag allow air to also blow out of bag.
As seen in detail in FIGS. 2 & 3 , all gusset members are sealed together. All gusset sides are pressed and all seals are applied including the long longitudinal seal and diagonal seal are applied at one time. The seals are made on both sides of the bag. FIG. 2 shows the smaller gussetted sides 18 to allow for a larger opening to load and unload any material in the bag. Note the reduced gusset side size 10 is to allow for maximum opening of the bag without destroying the integrity of the gussetted “square bottom” “flat bottom” bag.
FIGS. 2 and 3 clearly show the small slit 42 made in the bag to allow air to escape from the bag at time of loading, as well as the zipper closure to the bag along with a cut-out handle. The block seal 50 on the zipper portion of the closure is also clearly shown.
As seen from the foregoing, a “flat bottom” plastic bag be constructed of any desired size and for any selected use and function. The plastic film from which the bag is constructed can be transparent or opaque to allow for identifying and merchandising material. Seen in FIGS. 2 and 3 , a translucent film having a transparent window 44 is shown. The resultant bag has a triangular tubular shape. The “flat bottom” being larger in girth through the body of the bag, thereby allowing the bag to stand upright with the top distended to allow access and egress of material Similarly, the bag can be placed on its side as seen in FIG. 3 .
Furthermore, the bag allows the addition of a handle and a locking zipper or other closure device. Thereby, the resultant bag may be used as a handbag, pocket book or satchel tote.
Thus the scope of the disclosure should not be seen as limiting this invention should be derived only from the appended claims. | A tubular sleeve having an open top, a closed bottom wall, a front and back faces and a pair of opposing side walls connecting the front and back faces. The side walls are formed with at least one gusset allowing the front and back faces to extend from each other.
The gussets are sealed unitarily at the bottom ends to form the bottom wall. The “square bottom” bag takes on a triangular lengthwise shape normally biased closed at the top but easily openable for maximum filling and discharge of the interior of the bag. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates generally to foundry equipment and more particularly to a foundry molding machine for the production of mold halves in mold boxes. The invention particularly relates to a device for separating the mold halves from the pattern devices utilized in the production of the mold halves. The device to which the invention relates is of the type having a generally vertically extending cylinder including a piston rod which carries an extension connected to the piston rod and which is guided so that it may be raised and lowered whereby clamping devices on the extension may operate to engage in clamping relationship the mold boxes.
In the prior art there are known lifting and turning devices of a type which will deliver mold boxes to a molding machine and which will convey finished mold halves away from the machine. In such devices, the mold halves are usually lifted off the pattern devices in the formation of the mold halves.
Although devices of this type generally operate with reliability, in certain cases damage occurs when the mold member or mold half being formed is lifted from the pattern device. Generally, it has been found that the damage which occurs results mainly in pattern devices which are relatively insignificantly tapered and when the production process involves the production of molds with sand bales. Essentially, the invention is directed toward providing an approach which will enable operation of the lifting and turning device in a manner whereby during lifting of the mold halves relative movements between the mold boxes and the pattern devices which do not occur in a direction perpendicular to the plane of the pattern will be prevented or avoided. The invention thus seeks to enable more stable movement of the mold half off the pattern device with relative movement of the mold half occurring in a direction perpendicular to the plane of the pattern device until the mold half has been completely released from the pattern device.
SUMMARY OF THE INVENTION
The present invention may be described as a foundry molding machine for producing mold members in mold forming assemblies which include a pattern device and mold boxes, with the machine comprising means for separating mold members from the pattern device, the separating means including a generally vertically extending main cylinder having a piston rod operable to be raised and lowered by operation of the main cylinder. An extension member is connected to the piston rod and clamping means including clamping levers arranged in pairs on the extension member operate to hold the molding boxes in clamped engagement during release of the pattern device. The invention particularly provides at least one auxiliary cylinder arranged in a generally parallel relationship with the main cylinder and located in a laterally spaced relationship therewith on an opposite side of the mold members, the auxiliary cylinder being associated to operate with the main cylinder for acting on the extension means to provide support during separation of the mold members from the pattern device.
Thus, by virtue of the present invention, at least one second or auxiliary cylinder is arranged in generally parallel relationship to the main or first cylinder and spaced a distance therefrom with the second cylinder being located to act on the extension means on the side of the mold member or mold half opposite the first cylinder. The first and second cylinders are preferably operated by the same type of pressure medium and are advantageously connected to a common source of pressure medium and due to the fact that short feed lines controlled by a joint valve may be provided for the cylinders, pressure variations in the feed line will not create a damaging influence.
If two clamping devices are each arranged on two oppositely located sides of the mold box, the clamping forces applied may be smaller and may simultaneously make it possible to allow the clamping levers of the clamping devices to act at end faces of the mold box on a portion which is constructed as a prismatic bar. Thus, the mold bar is not elastically deformed when it is being grasped during operative movement of the apparatus.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a schematic representation showing in plan view a molding machine including a lifting and turning device and conveyor means for delivering and carrying away mold boxes or mold halves;
FIG. 2 is a sectional elevation taken in the direction of the arrow A of FIG. 1 along the line II--II of FIG. 1;
FIG. 2a is a partial sectional view taken along the line IIa--IIa of FIG. 2;
FIG. 3 is a schematic elevational view of the apparatus shown in FIG. 2 taken in the direction of the arrow B;
FIG. 4 is a partial sectional view showing clamping devices of the apparatus and taken in the direction of an arrow C in FIG. 3; and
FIG. 5 is a partial sectional view taken along the lines V--V of FIG. 3.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, a lifting and turning device 2 includes clamping devices 8 with two such clamping devices being arranged each on each side of extension members 4 and 6. The extension members 4 and 6 are generally formed in the shape of a frame.
The system includes a molding unit 10 and a position 12 at which a mold forming assembly, which includes a pattern device 16 and a mold box or mold half 18 operatively associated with the pattern device, may be filled with mold forming material. The mold half 18 is conveyed between the position 12 and the molding unit 10 by means of a conveyor device 14.
As shown in FIG. 1, a first or main cylinder means 20 and a second or auxiliary cylinder means 22 are provided. On a conveyor device 26, mold boxes 24 and mold halves 34 are moved in a fixed-cycle type of operation in the direction of an arrow 28.
Clamping devices 8 operate to grasp the mold boxes 24 in the position 30 and the mold halves in the position 12. Mold boxes 24 and the mold halves 18 may be lifted by the lifting and turning device 2 and they may be turned through a half turn in the direction of arrow 32 by operation of the device 2. Subsequently, by lowering the lifting and turning device 2, a mold box 24 in the position 12 can be lowered onto the pattern device 16 and a mold half 18 in the position 30 can be lowered onto the conveyor device 26.
After all clamping devices 8 have been opened, the lifting and turning device 2 can be lifted. In the position 12, molding sand is filled into the pattern device 16 which has a mold box 24 placed thereupon. Subsequently, the pattern device 16 is moved into the molding unit 10 by means of the conveyor device 14. Here, the mold forming material is compacted and the compacted mold unit or member is again moved back into the position 12. Simultaneously, mold boxes 24 and the mold halves 18 and 34 which have been placed on the conveyor device 26 are moved through a predetermined distance in the direction of arrow 28. Thereafter, a new cycle of operation may be commenced. As best seen in FIGS. 2 and 3, the cylinder means 20 and the second or auxiliary cylinder means 22 are supported upon a base plate 52 which is, in turn, supported upon a foundation 50. Through columns 54, the base plate 52 carries a support 56, the pattern device 16 and a mold half 18. A piston 60 including a piston rod 64 of the lifting and turning device 2 is connected to an extension 68 and is guided in a cylinder 62 and in guideways 66 in a manner enabling raising and lowering thereof. The piston rod 64 is secured against rotation relative to the guideways 66 by means of a key 70. Through the guideways 66 and the piston rod 64, a gear 72 turns with reciprocating motion the extensions 68,4 and 6 by a half turn in the direction of arrow 32 (see FIG. 1). The apparatus includes drive means (not shown) operatively engaging the gear 72. The cylinder 62 is held in a bearing 76 and the guideways 66 are held in a bearing 78. The rotatable parts are supported on a surface 80.
Clamping levers 90 of the clamping devices 8 are actuated by cylinders 94 which are pivoted to the clamping levers 90 which operate in pairs (FIG. 4). Clamping surfaces 91 are constructed as end faces of rod-shaped mold box portions 93. The design depicted has the advantage that the clamping forces, which may be on the magnitude of ten tons or more, will not noticeably elastically deform the mold box of the mold half 18. inasmuch as the forces which are applied are exclusively absorbed by the rod-shaped parts 93. Two clamping devices 8 arranged on the same side of the mold box are supported in a joint part 92 through their clamping levers 90. The arrangement of two clamping devices 8 each on a side of the mold box 24 or the mold half 18 makes it possible to maintain the length of the mold box parts 93 relatively small and to arrange the latter near the corners of the mold box whereby the mold box is not deformed as a result of torsional forces which may occur during the process of separation.
Each of two pins 108 which include flange-like ends are arranged below the cylinder 100 (FIGS. 1 and 5) and operate to support the part 92 in a flange bearing 114 without play in the vertical direction and with the ability to move in the horizontal direction within a degree of play 96. The flanged bearings 114 are attached to the extension 68.
When a feed line of the cylinder 100 is switched to exhaust, a spring 102 moves a piston 98 into a position 104 and releases the pin 108. Thus the part 92 is also released in the horizontal direction. However, when the cylinder 100 is supplied with pressure medium, the piston 98 moves into a position 112 and the pin 108 locks the part 92.
The second or auxiliary cylinder 22 is mounted upon the base plate 52 and is arranged relative to the mold half 18 on the side thereof opposite the side on which the main or first cylinder 20 is located. In a raised position 144 of its piston rod 142, a stroke 147 of a piston 140 is limited by a cylinder surface 146. In the lowered position depicted in FIG. 2, the piston rod 142 abuts the extension 68. Since the extensions 4,6 and 68 are constructed as a frame and since the piston rod 142 acts immediately beneath the frame 68, the force of the piston rod 142 will not cause deformation due to torsional forces during the process of separation of the mold halves 18 from the pattern device 16.
In the example described, the size of the cylinder 62 is selected in such a manner that the piston 60 may lift the parts that are connected thereto and also the mold box 24 and the mold half 18. On the other hand, the size of the cylinder 148 depends upon the size of the cylinder 62. The size of the cylinder 148 may be determined, by way of example, in accordance with rules of mechanics from the weights of the mold half 18, the mold box 24, the piston 60 and the parts 64,4, 6 or 68,8 connected to the latter, from the weight of the piston 140 including the piston rod 142 and from the friction of sand of the mold half 18 at the pattern device during separation. When reliable values for the forces necessary for overcoming friction of the sand at the patterns are not available, the size of the cylinder 148 may also be determined experimentally by inserting sleeves having bores of various diameters in the cylinder 148. In this connection, it should be taken into consideration that the product of lifting forces of the cylinder 62 minus the weight of the mold box 24 and minus the weight of the parts connected to the piston 60, multiplied by a distance a corresponds to the product of the lifting forces of the cylinder 148 multiplied by a distance b.
When a valve 152 is in appropriate position, a feed line 150 will supply pressure medium through a feed line 154 to the cylinder 148 and through a feed line 156 to the cylinder 62. By reversing the valve 152, the cylinders 148 and 62 will discharge through a discharge line 158. It is advantageous to adjust relative to each other the feed lines 154 and 156 as well as the flow conditions into the cylinders 148 and 62.
A description of the manner of operation of the apparatus of the present invention may commence from the assumption that a mold half 18 ready for lifting is in the position 12 and that a mold box 24 is in the position 30. Furthermore, the lifting and turning device 2 with open clamping devices 8 may be assumed to be in the lowered position in accordance with FIGS. 2 and 3. In this condition, the only forces acting upon the piston rod 64 result from the natural weights of the extensions 4,6 and of the clamping devices 8.
When the cylinder 94 is reversed, the clamping devices 8 of the extension 6 will grasp the mold box 24 and the clamping devices of the extension 4 will grasp the mold half 18. The parts 92 are locked since pressure medium is supplied to all cylinders 100. The piston rod 142 rests against the extension 4, 68. By reversing the valve 152 from the discharge position 158 to the feed line 152, the pressure medium will flow simultaneously and with equal pressure to the cylinders 62 and 148.
It is advantageous to control the beginning of the piston strokes 147, 145 by providing plugs 160 (see FIG. 2a) which project into the feed lines 154 or 156 or which are connected to a piston 140 or 60. While the mold half 19 performs a partial stroke which extends at least up to complete disengagement of a mold half 18 from the pattern device 16, the piston 140 continues to rest against the surface 46. The piston rod 142 concludes its stroke 147 in the raised position 144 and the cylinder 20 by itself raises the lifting and turning device 2 along the remaining path of the raised 149.
When the extension 4,6 is raised into the position 149, the lifting and turning device 2 is turned through half a turn in the direction of arrow 32 and is then lowered by reversing the valve 152. During the lowering process, the cylinders 100 of the extension 6 are switched to exhaust so that the grasped mold box 24 can be adjusted in a horizontal direction to the position of the dowel guide of the pattern device 16. By reversing the cylinder 94 the clamping devices 8 will be opened and by reversing the valve 152 the lifting and turning device 2 will be raised. Thus, the mold half 18 will have been lifted off the pattern device 16 and another mold box 24 may be placed on the pattern device 16.
It should be noted that cylinder means 20 and 22 are preferably of the same type and may either be of the hydraulic or pneumatic type. Consequently, feed line 150 will be connected to a corresponding source of either hydraulic or pneumatic pressure medium (not shown) depending on the type of cylinder means chosen. Preferably cylinders 94 and 100 are of the same type which is chosen for cylinder means 20 and 22 so that a common source of pressure medium may be used for the operation of all cylinders.
In any event, if heavy and large mold halves are to be produced the employment of hydraulic main and auxiliary cylinder means is preferred.
Utilization of the device of the present invention need not be limited to provision of a specific number of extensions 4,6,68 or to a particular number of clamping devices 8. Furthermore, the apparatus of the invention may be provided with more than one auxiliary or "second" cylinder 22.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles. | A foundry molding machine for producing mold halves in mold forming assemblies which include a pattern device and mold boxes and operates to separate the formed mold halves from the pattern device through operation of a generally vertically extending main cylinder which includes a piston rod having an extension thereon. The extension includes clamping levers which are arranged in pairs to hold the mold boxes in clamped engagement. At least one auxiliary cylinder is arranged in generally parallel relationship with the main cylinder and is located in a laterally spaced arrangement relative thereto for operation on the opposite side of the clamped mold box. The auxiliary cylinder is operatively associated with the main cylinder to be simultaneously supplied with pressure medium from a common source and acts on the extension to provide support during separation of the mold members from the pattern device. | 1 |
BACKGROUND
The present invention relates to field effect transistor (FET) devices, and more specifically, to methods for fabricating FET devices.
FET devices include source, drain, and channel regions. The source and drain regions include doped ions. The source and drain regions may be doped using ion implantation methods following the formation of the source and drain regions, or may be doped during the formation of the source and drain regions. Stress liner material may be formed proximal to the channel regions. The stress liner material often enhances the carrier mobility and performance of the FET devices.
BRIEF SUMMARY
According to one embodiment of the present invention, a method for forming a field effect transistor device includes forming a gate stack portion on a substrate, forming a spacer portion on the gates stack portion and a portion of the substrate, removing an exposed portion of the substrate, epitaxially growing a first silicon material on the exposed portion of the substrate, removing a portion of the epitaxially grown first silicon material to expose a second portion of the substrate, and epitaxially growing a second silicon material on the exposed second portion of the substrate and the first silicon material.
According to another embodiment of the present invention, a field effect transistor device includes a gate stack portion disposed on a substrate, a first cavity region in the substrate arranged on a first side of the gate stack portion, a second cavity region in the substrate arranged on a second side of the gate stack portion, a first epitaxially grown silicon material disposed in the first cavity region and the second cavity region, and a second epitaxially grown silicon material disposed in the first cavity region and the second cavity region, the second epitaxially grown silicon material in contact with the first epitaxially grown silicon material.
According to yet another embodiment of the present invention, a field effect transistor device includes a first gate stack portion disposed on a substrate, a second gate stack portion disposed on the substrate, a cavity region in the substrate arranged between the first gate stack portion and the second gate stack portion, a first stressor portion disposed in the cavity region adjacent to a channel region of the first gate stack portion, a second stressor portion disposed in the cavity region adjacent to a channel region of the second gate stack portion, and a doped material disposed in the cavity region on the substrate, the first stressor portion and the second stressor portion.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention. For a better understanding of the invention with the advantages and the features, refer to the description and to the drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The forgoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
FIGS. 1-7 illustrate side views of a method for forming field effect transistor (FET) devices and the resultant structure of the devices.
FIGS. 8-10 illustrate side views of an alternate method for forming field effect transistor devices and the resultant structure of the devices.
DETAILED DESCRIPTION
FIGS. 1-7 illustrate side view of a method for forming field effect transistor (FET) devices and the resultant structure of the devices. Referring to FIG. 1 , gate stacks 102 a and 102 b , referred to collectively as gate stacks (gate stack portions) 102 hereinafter, are formed on a silicon on insulator (SOI) substrate 100 . The gate stacks 102 may include, for example, a dielectric layer 104 such as a high-K layer or oxide layer and a metal layer 106 disposed on the dielectric layer 104 . A silicon capping layer 108 is disposed on the metal layer 106 . A spacer (spacer portion) 110 is patterned over the gate stacks 102 and a portion of the substrate 100 . The spacer 110 may include, for example, a nitride or oxide material. In the illustrated embodiment, the spacer 110 also includes a hardmask portion over the gate stacks 102 .
FIG. 2 illustrates the resultant structure following an anisotropic etching process such as, for example, reactive ion etching (RIE) that forms a trench (cavity region) 202 in the substrate 100 between the gate stacks 102 a and 102 b . Once the trench 202 is formed, the gate stacks 102 that will become n-type (NFET) devices, for example gate stack 102 a , may be isolated by patterning a layer of nitride (not shown) over the gate stacks 102 , leaving the gate stacks 102 that will become p-type (PFET) devices exposed.
FIG. 3 illustrates regions 302 that may be formed by implanting ions, such as, for example, boron ions, in the substrate 100 . In the illustrated embodiment, the regions 302 facilitate isolating adjacent devices such as devices to be formed by gate stacks 102 a and 102 b . The regions 302 are formed in the substrate 100 below the channels 202 , however, in some embodiments, the sidewalls of the channels 202 may also be implanted with ions using, for example, an angled implant process. In alternate embodiments, the regions 302 may not be formed with ion implantation.
FIG. 4 illustrates the resultant structure following the epitaxial growth of a silicon-containing material (epi-silicon) 402 on the exposed portions of the substrate 100 . In the illustrated embodiment, the epi-silicon 402 may include, for example, SiGe with greater than 30% (by atomic percentage) Ge content. Alternate embodiments may include between 20-50% Ge content. The epi-silicon 402 material may be undoped, low doped, or counter doped (e.g., doping an n-type region with p-type dopants or doping a p-type region with n-type dopants). In alternate exemplary embodiments, the epi-silicon material 402 may include, for example, SiC or other compound that may be used to form NFET devices. The formation of epi-silicon 402 SiC material includes multiple cycles of epitaxial SiC growth and etching to form the material 402 . The carbon (C) content in the epi-silicon SiC may range from approximately 1% to 5%. The epi-silicon SiC may be undoped, low doped (i.e., doped with phosphorous or arsenic) or counter doped.
FIG. 5 illustrates the resultant structure following an etching process that removes portions of the epi-silicon material 402 . The etching process may include, for example, a hydrogen chlorine (HCl) etch preformed in the epitaxy chamber, or other etching processes such as NH 4 OH or Tetramethylammonium Hydroxide (TMAH) wet etching processes. The etching process etches the epi-silicon material 402 at a faster rate than the silicon substrate 100 . The crystalline structure of the epi-silicon material 402 and the etching process results in the formation of stress regions 501 partially defined by a plane 500 arranged [1,1,1] (using Miller index notation). The stress regions 501 are adjacent to the channel regions 503 of the devices. The etching process exposes a portion of the substrate 100 in the region 502 , between the devices.
FIG. 6 illustrates the resultant structure following the epitaxial growth of doped silicon material 602 that forms the source regions (S) and drain regions (D) of devices 601 a and 601 b , hereinafter devices 601 . In the illustrated embodiment, the doped silicon material 602 includes a doped SiGe material that is epitaxially grown from the exposed substrate 100 and the stress regions 501 . The dopant may include, for example boron, arsenic, or phosphorous ions.
FIG. 7 illustrates the resultant structure following the removal of a portion of the spacer 110 that exposes the gate stacks 102 a and 102 b and defines gate regions (G) of the gate stacks 102 . The portion of the spacer material 110 may be removed by, for example, a chemical mechanical polishing process, or a suitable etching process. Once the gate regions (G) have been exposed, a silicide may be formed on the exposed source, gate, and drain regions, and conductive contact material may be formed on the regions (not shown).
In an alternate embodiment, a similar etching process described above in FIG. 5 may remove portions of the epi-silicon material 402 and the SOI substrate 100 . The etching process may include etchant parameters such as etchant chemicals that selectively etch both the epi-silicon material 402 and the silicon substrate 100 material. FIG. 8 illustrates the resulting structure following the removal of portions of the epi-silicon material 402 and the SOI substrate 100 that results in the formation of undercut regions 802 . The undercut regions 802 may expose a portion of the gate stacks 102 .
FIG. 9 illustrates the resultant structure following the epitaxial growth of doped silicon material 602 that is similar to the process described above in FIG. 6 .
FIG. 10 illustrates the resultant structure following the removal of a portion of the spacer 110 that is similar to the process described above in FIG. 7 .
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The embodiment was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use contemplated
The diagrams depicted herein are just one example. There may be many variations to this diagram or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order or steps may be added, deleted or modified. All of these variations are considered a part of the claimed invention.
While the preferred embodiment to the invention had been described, it will be understood that those skilled in the art, both now and in the future, may make various improvements and enhancements which fall within the scope of the claims which follow. These claims should be construed to maintain the proper protection for the invention first described. | A method for forming a field effect transistor device includes forming a gate stack portion on a substrate, forming a spacer portion on the gates stack portion and a portion of the substrate, removing an exposed portion of the substrate, epitaxially growing a first silicon material on the exposed portion of the substrate, removing a portion of the epitaxially grown first silicon material to expose a second portion of the substrate, and epitaxially growing a second silicon material on the exposed second portion of the substrate and the first silicon material. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a refractory gas-permeable structural unit for blowing a gas into a metal treatment vessel and through its casing.
The oxygen top-blowing methods used in pig iron refining, which are known under the names of "LD"-, "LDAC"-, "OLP"-, "BOF"-methods, are recently improved, as far as the metallurgy is concerned, in that secondary gases, such as nitrogen or argon, are blown under controlled conditions through the converter bottom. Also, in other metal treatment vessel like ladles for aftertreatment of steel or electric arc furnaces, the blowing of gas into the metal bath through the bottom of the vessel or the casing of the vessel wall is taken into consideration.
The gas-permeable refractory stones which are inserted into the casing of the bottom or the lateral wall of the vessel to perform the gas supply must satisfy the requirement that their stability must correspond to the stability of the refractory casing, inasmuch as an exchange of the connected gas-permeable stones in hot condition in a vessel bottom is substantially difficult. It is also necessary to provide the gas supply which can be continuous and also discontinuous; in other words, the vessel must be able to operate without gas supply, and after the repeated switching of the gas supply the stones must be gas-permeable in the same manner. Moreover, the gas-permeability of the stones during their service life, that is during the entire life of the furnace, must remain substantially constant.
The known gas-permeable stones of porous refractory material do not satisfy these requirements. Their stability in refining vessel is considerably smaller than the stability of the surrounding casing material. Thus, the porous stones embedded in the bottom of an oxygen converter withstand less than 100 charges, whereas the stability of the lining itself is 500 charges and more. Furthermore, a discontinuous gas supply is not possible with the porous stones; the metal penetrates into the pores of the stone and hardens there. After switching on the gas supply, the stone is no longer sufficiently gas-permeable.
In the patent application LU 81,208 applicants disclose a device which can be inserted into the bottom of a metal treatment vessel for blowing a treatment gas into a metal bath, which has a considerably improved stability with respect to the hitherto known gas-permeable stones, and which permits the blowing of the desired gas quantities. This device essentially consists of a refractory gas-permeable structural unit, whereby in an axial direction of the refractory material a plurality of flat, wave-like, pipe-like or wire-like metallic separating members of a low wall thickness are embedded. In accordance with one embodiment, this structural unit consists of steel sheet metal and segments or strips of refractory material in alternating disposition.
For manufacturing such a structural unit, it is necessary to cut a prefabricated block of refractory material into the required strips or segments, which is a very expensive manufacturing process. Since the segments have as a rule a very small thickness and a great length, the segments manufactured by compressing refractory "material" are not sufficiently easy to handle and warp when they are subjected to burning.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a refractory gas-permeable unit which avoids the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a refractory gas-permeable unit which is easy to manufacture and has segments with sufficient stability.
It is a further object of the present invention to provide a refractory gas-permeable structural unit which has an increased gas-permeability without affecting the high stability of the structural unit.
In keeping with these objects, and with others which will become apparent hereinafter, one feature of the present invention resides, briefly stated, in a gas-permeable structural unit which has at least two elements composed of a refractory material and abutting against one another with their first longitudinal faces, a metal layer arranged on at least one of the first longitudinal faces of the elements, a metal housing surrounding the elements to connect them with one another and sealingly abutting against second longitudinal faces of the elements, and a gas distribution chamber with a gas conduit formed at one end face of the elements.
The elements or segments may be composed of burnt or unburnt material, for example including a carbon-containing binder such as tar, pitch, plastic resin, or a chemical binder. A mortar layer may be provided between the second longitudinal faces of the elements and the metal housing.
In accordance with another feature of the present invention, the metal layer may be compressed with the refractory material of the elements. Because of the provision of the compressed metal layer, the manufacturing and handling of the relatively thin elements with great lengths is considerably facilitated, inasmuch as the metal layer serves as a reinforcement of the element, increasing the stability of the latter. The utilization of elements or bodies with compressed metal layers makes easier the assembling of several segments into a structural unit, inasmuch as the insertion of sheet plates can be dispensed with. Despite this, metal plate pairs may be inserted between the elements, if necessary.
In accordance with still another feature of the invention, the metal layer can lie on the refractory material of the elements, without being compressed with the latter. Whether the metal layer is compressed with the refractory material or it merely lies on the latter, a further feature of the invention resides in the fact that the neighboring longitudinal faces of the elements may be smooth or profiled, for example formed with wave-like or groove-like outer faces.
In accordance with still a further feature of the present invention, the elements may abut against one another with interposition of metal plates, metal plate pairs, and/or spacing members. The spacing members may be formed as portions of the metal layers which are shaped as corrugations or knubs, as sheet strip, as wires, or as combustible or vaporizable inserts, and so on.
In accordance with an additional feature of the present invention, an additional metal layer is provided on the first-mentioned metal layer compressed with the refractory material and formed as a sheet plate which is, for example, welded with the first-mentioned layer, whereas the abutting longitudinal face of the neighboring element is free of metal layers.
The profiling or shaping of the longitudinal faces of the elements of refractory material, formed as waves, grooves, notches, and so on, can be performed by cutting or milling of prefabricated elements. It is also possible to provide the profiling during the manufacture of the elements so that the pressing plunger or the shaping walls of the pressing mold is designed with a corresponding negative profile, and thereby the elements with the required profiling on the longitudinal faces are obtained.
The manufacture of the elements with the compressed metal layers having profiled outer faces can be performed in a simple way by providing the pressing plunger or the pressing mold wall with the respective profiling, such as wave-like or groove-like profiling, and introducing first a flat sheet plate and a refractory mass into the pressing mold. During the pressing step, the profiling of the compressed sheet plate is automatically obtained.
When the elements with the profiled metal layers are assembled, a structural unit is obtained which has gaps, passages through which the gas supply can be performed whereas the profiled longitudinal faces abut against smooth or profiled longitudinal faces of the neighboring element. The abutting longitudinal faces of the neighboring elements can in turn be provided with a compressed metal layer or they can be free of the latter.
In accordance with an additional feature of the present invention, some or all elements can be provided with at least a compressed-embedded pair of abutting metal inserts, for example sheet plates, embedded thereinto. Spacing members of the above mentioned type can be provided between the metal plates of the insert pair. The degree of gas-permeability can be varied in dependence upon the number of the embedded insert pairs as well as upon the construction of the spacing members.
When the compressed insert pairs are utilized, the structural unit can be manufactured in a simple way so that a portion of the refractory material is first introduced into the pressing mold, then the insert pair is introduced thereinto so that it extends over the entire length of the stone but only over a portion of the stone width, and finally another portion of the refractory material is introduced. When the structural unit has more than one insert pair, the process is repeated accordingly. Then the pressure is applied normal to the insert and the structural unit is molded. After removal of the unit from the press, the inserts are released at the end faces of the structural unit so as to make possible the gas passage. Instead of a plates pair, a folded sheet or a compressed pipe can be inserted into the elements. Moreover, multi-layer inserts, provided if necessary with spacing elements, can also be utilized.
The degree of gas permeability of the structural unit can be varied in dependence upon the number of insert pairs embedded in the element. Since the refractory material used for the structural unit corresponds to the material of the lining, the structural unit has the same stability as the surrounding lining. A premature replacement of the gas-permeable stones is not required.
It has been shown that the structural units can operate without gas supply. In this case, some metal penetrates into the naarrow slot between the inserts of one pair, and during the subsequent switching of the gas supply this metal is forced out of the structural unit so as to resume the original gas-permeability. This phenomenon remains during the entire lifetime of the structural unit in a considerably uniform manner.
The novel features which are considered characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of preferred embodiments when read in connection with the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a view showing a refractory gas-permeable structural unit for blowing a gas into a metal treatment vessel, in accordance with a first embodiment of the invention;
FIGS. 2-7 are views showing elements of the inventive structural unit;
FIG. 8 is a view showing a structural unit with a compressed-embedded metal pair;
FIG. 9 is a view substantially corresponding to the view of FIG. 1, but showing another embodiments of the invention with the elements shown in FIG. 6; and
FIG. 10 is a view substantially corresponding to the view of FIG. 1 but showing a further embodiment of the invention with the elements shown in FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A refractory gas-permeable structural unit for blowing a gas into a metal treatment vessel and through its casing is shown in FIG. 1 and identified in toto by reference numeral 1. It has a metal housing 2 composed of several plates which are, for example, welded with one another. The housing embraces twelve elements or segments 3 arranged in two rows each containing six elements. Each element 3 has a compressed metal layer 4. Each element 3 abuts with its exposed lateral face against the inner surface of the metal housing 2, with interposition of a not shown mortar layer. Thereby, the undesirable gas passage which cannot be controlled, along the metal housing is prevented.
A sheet plate 5 is inserted between two rows of the segments 3. A gas passage can be performed along the sheet plate 5 as well as along the metal layer 4 of the segments 3. Instead of the sheet plate 5, also a plate pair can be arranged between the rows of the segments 3. The sheet plate 5 or the plate pairs can be connected by mortar.
The elements 3 are arranged at a distance from the end side of the metal housing because of the provision of two strips 6 which are provided at the inner side of the metal housing 2 and connected with the latter preferably by point welding. At this side, which is the cold side, an end plate 7 is sealingly welded and provided with a tubular connection 8. A space which is formed between the end sides of the elements 3 and the end plate 7 forms a distributing chamber for the gas.
The other side of the structural unit which is opposite to the end side 7 is the fire side of the structural unit and can be provided with a cover sheet. This cover sheet is utilized when the structural unit is surrounded by the metal treatment vessel lining with a tar and other carbon-containing materials. It prevents penetration of tar or other materials into the gas passage gaps of the structural element and hardening the same during heating of the vessel. The cover sheet melts in the beginning of the operation and releases the gap. A not shown bracket may also be provided in the region of the fire side of the structural unit, so that the structural unit can be suspended on a crane hook.
FIGS. 2, 3 and 4 show elements 30, 31 and 32 which have two, three or four longitudinal faces provided with compressed metal layers 4, 41 and 42. The metal layers may have claws 9 which extend into the refractory material of the elements for improved connection with the latter and are produced by punching out.
An element 33 which is shown in FIG. 5 has the compressed metal layer 4 and an additional second metal layer 43. The additional metal layer 43 is connected with the metal layer 4 by point welding. The segments 30, 31, 32 and 33 can be inserted into the structural unit of FIG. 1 instead of the elements 3.
FIG. 6 shows an element 34 which is provided with profiled and corrugated metal layer 44 at its one longitudinal face and the flat metal layer 4 at its other longitudinal face. When the segments 34 are assembled with one another, a passage for the gas extends in the longitudinal direction of the structural unit.
FIG. 7 shows an element 35 which can replace three elements 3 of the structural unit of FIG. 1. The element 35 has a compressed metal layer 45 and two pairs of sheet inserts 10 which extend over the entire length of the element 35 but at the same time extend only over a portion of its width. In dependence upon the desired gas permeability, the insert 10 may be formed as smooth sheet strips or, as shown in FIG. 8, as shaped sheet strips provided with corrugations or grooves 11 forming spacing members. The insert 10 may be provided with the claws 9 for improving their connection with the refractory material of the elements.
The structural unit 1 shown in FIG. 9 has the metal housing 2 surrounding twelve elements which are arranged in rows each containing six elements. Each element is provided at its longitudinal side with a profiling. More particularly, the upper elements 34 have profiling shaped as grooves, whereas the lower elements 34 have profiling shaped as waves. In practice, however, all segments have generally identical profiling.
Flat sheet plates are located in the gaps between two neighboring segments of each row. However, the inserts with profiling can also be inserted therebetween. An insert shaped as a sheet plate pair is arranged between two rows.
The structural unit 1 shown in FIG. 10 has the metal housing 2 which embraces four segments 35. The segments abut with their U-shaped compressed metal layers 45 against one another. The exposed longitudinal sides of the segments abut against the inner surface of the housing which is composed, for example, of plates welded with one another.
The metal inserts may be composed of a steel sheet which, for example, has a thickness between 0.5 and 3 mm and may be provided with a surface protection, if necessary. The elements may be composed, for example, of tarbound mass of magnesia having the following composition and granule structure:
______________________________________Sinter magnesia Granule structure______________________________________MgO 96.2 weight % 5-8 mm 20 weight %Fe.sub.2 O.sub.3 0.2 weight % 3-5 mm 15 weight %Al.sub.2 O.sub.3 0.1 weight % 1-3 mm 20 weight %CaO 2.5 weight % 0-1 mm 20 weight %SiO.sub.2 1.0 weight % 0-0.1 mm 25 weight %______________________________________
The sintered magnesia is provided with 4 wt.-% of coal tar pitch as a binder. Also other tars, pitches, plastic resins and the like may be utilized as binders.
A further mass for manufacturing a stone to be utilized in the structural element in accordance with the present invention has the following composition and granule structure:
______________________________________Prereacted magnesia-chromeore-sinter granular Chrome ore______________________________________MgO 53.8 weight % 17.1 weight %Cr.sub.2 O.sub.3 19.2 weight % 53.2 weight %Al.sub.2 O.sub.3 4.2 weight % 10.4 weight %Fe.sub.2 O.sub.3 9.8 weight % --FeO -- 15.9 weight %CaO 1.8 weight % 0.1 weight %SiO.sub.2 1.2 weight % 3.3 weight %______________________________________Granule______________________________________sinter granular 3-5 mm 20 weight %sinter granular 1-3 mm 25 weight %sinter granular 0-1 mm 25 weight %sinter granular 0-0-1 mm 20 weight %chrome granular 0-0.7 mm 10 weight %______________________________________
The components are mixed for chemical binding with 3.7 wt.-% of kieserite solution with a density of 1.22 g/cm 3 .
The invention is, however, not limited to the above-mentioned refractory materials. Other refractory materials also can be utilized, such as for example mixtures of magnesia and chrome ore, a high-alumina material.
The inventive structural unit possesses a sufficient gas permeability, whereas the gas passage is performed through the gaps between the individual elements, on the one hand, and through the gaps between the metal inserts, on the other hand. The elements themselves possess practically no gas permeability, and thereby the refractory material utilized for the structural unit corresponds to the lining of the metal treatment vessel. Thereby the gas-permeable structural element has the same stability as the surrounding lining, and a premature replacement of the gas-permeable structural unit is avoided.
In accordance with the present invention, each gap in the structural unit through which a gas passage is performed must be provided with a metal plate, either formed as a metal layer on the elements, or formed as metal plates arranged between the elements. As mentioned above, these metal layers or metal plates prevent penetration of metal from the metal bath of the treatment vessel into the gaps, and also in the event of the treatment of pig iron which, because of its consistency and viscosity, has an especially considerable inclination to penetrate into the gaps.
This phenomenon may be explained by the fact that the metal plates arranged in the gas-permeable gaps provide for a cooling action, and the heat is conveyed fast to cold end faces of the structural elements. Thereby, the penetrated metal to be treated hardens after a short stroke (several centimeters). When the gaps are not provided with metal plates or metal layers, the penetration of metal up to the cold end face is observed.
It should be mentioned that not only the metal inserts, but also the metal layers may be formed of steel sheet. The metal layers or the metal plates between the elements may be formed similar to the metal inserts 10. More particularly, they may have spacing members formed as corrugations or knubs in the metal layers or metal plates, and also as wires, metal strips, or combustible or vaporizable insertable members arranged between the metal layers or metal plates.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.
While the invention has been illustrated and described as embodied in a refractory gas-permeable structural unit for blowing a gas into a metal treatment vessel and through its casing, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | A refractory gas-permeable structural unit for blowing a gas into a metal treatment vessel and through its casing has at least two elements composed of refractory material and having abutting longitudinal faces provided with at least one metal layer, a metal housing surrounding the elements to connect them with one another and tightly abutting against other longitudinal faces of the elements, and a gas distribution chamber formed at an end face of the elements and communicating with a gas supply conduit. | 2 |
CROSS-REFERENCE TO OTHER APPLICATIONS
[0001] This application claims the benefit of the following provisional patent applications: 60/704,230 filed on 28 Jul. 2005 and entitled Liquid Heater Capsule for Treatment of Onychomycosis and Other Nail Infections; 60/709,602 filed on 8 Aug. 2005 and entitled Protective Glove for Hand or Foot during Submersion Nail Treatment; and 60/731,754 filed on 30 Oct. 2005 and entitled Liquid Heater Compress for Treatment of Onychomycosis and Other Nail Infections.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] None.
BACKGROUND OF THE INVENTION
[0003] Tinea unguium or onychomycosis (nail fungus) has long been a medical challenge to cure. While there are topically applied reagents which effectively control fungal growth (e.g., cyclopirox) getting the reagent to thoroughly contact the fungus has long been the challenge. The nail provides a seemingly impenetrable membrane protecting the fungus from outside elements as Quintanar-Guerrero et al from Universidad Nacional Autonoma de Mexico have shown in their paper, The effect of keratolytic agents on the permeability of three imidazole antimycotic drugs through the human nail (Drug Dev Ind Pharm, Jul. 1, 1998; 24(7): 685-90).
[0004] Current topical treatment research has focused on developing a single reagent which both penetrates the nail and destroys the fungus. Unfortunately, to date such research has not produced this cure. Ciclopirox (Penlac, Loprox) alone has a cure rate of just 20% after one year, however, this rate may include data for Ciclopirox' primary purpose, that is, tinea corporis. Part of the challenge is developing a single treatment for the 119 known strands of tinea.
[0005] Quintanar-Guerrero et al also found that keratolytic substances such as papain, and salicylic acid used in combination did enhance the permeability of the antimycotic.
[0006] Patents with methods, formulae, and apparatus to increase the permeability of the antimycotic through the nail into the nail bed dominate this art See, for example, the following U.S. patents and patent application publications: U.S. Pat. Nos. 6,821,508; 6,921,529; 5,795,314; 5,098; 4,331,137; 2004/0161452 A1; 2006/0013862; 6,727,401; 6,465,709.
BRIEF SUMMARY OF THE INVENTION
[0007] A first aspect of the invention is directed to apparatus for treating an infected nail of a digit of a patient. The apparatus includes an enclosure capable of housing at least a distal end of at least one digit of a patient having an infected nail. The apparatus also includes a heater and a nail infection agent-containing member housed within the enclosure and positionable against an infected nail at the distal end of a digit housed within the enclosure. The heater is in heat-transfer relationship with the nail infection agent. In this way heated nail infection agent can be maintained against an infected nail by the nail infection agent-containing member.
[0008] A second aspect of the invention is also directed to apparatus for treating an infected nail of a digit of a patient. The apparatus includes means for housing at least a distal end of at least one digit of a patient having an infected nail. The apparatus also includes means, within the housing means, for positioning a nail infection agent-containing member against an infected nail at the distal end of a digit housed within the enclosure. In addition, the apparatus includes means for heating the nail infection agent. The nail infection agent can thereby be maintained against an infected nail by the agent-containing member.
[0009] A third aspect of the invention is directed to a method for treating an infected nail of a digit of a patient. At least a distal end of at least one digit of a patient, having an infected nail, is housed within an enclosure. A nail infection agent-containing member is positioned against an infected nail at the distal end of a digit housed within the enclosure. The nail infection agent is heated to enhance the effectiveness of the nail infection agent. The heated nail infection agent is maintained against the infected nail for a therapeutically effective time period. In some embodiments the nail infection agent is restrained or prevented from coming into contact with a patient's skin. The nail infection agent may also be restrained or prevented from escaping from the enclosure.
[0010] Various features and advantages of the invention will appear from the following description in which the preferred embodiments have been set forth in detail in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] FIG. 1 is a first simplified isometric view of a first preferred embodiment of an infected nail treatment apparatus mounted to a digit of a user;
[0012] FIG. 2 is a second simplified isometric view of the apparatus of FIG. 1 ;
[0013] FIG. 3 is a simplified cross-sectional view of the apparatus of FIG. 1 ;
[0014] FIG. 4 is a simplified isometric view of the apparatus of FIG. 1 in an unfolded state;
[0015] FIG. 5 is a first simplified isometric view of a second, alternative embodiment of an infected nail treatment apparatus mounted to a digit of a user;
[0016] FIG. 6 is an exploded isometric view of the apparatus of FIG. 5 ; and
[0017] FIG. 7 is a simplified cross-sectional view of the apparatus of FIG. 5 .
DETAILED DESCRIPTION OF THE INVENTION
[0018] The following description of the invention will typically be with reference to specific structural embodiments and methods. It is to be understood that there is no intention to limit the invention to the specifically disclosed embodiments and methods but that the invention may be practiced using other features, elements, methods and embodiments. Preferred embodiments are described to illustrate the present invention, not to limit its scope, which is defined by the claims. Those of ordinary skill in the art will recognize a variety of equivalent variations on the description that follows. Like elements in various embodiments are commonly referred to with like reference numerals.
[0000] The Treatment Apparatus of Preferred Embodiment
[0019] The design intent for the embodiment of FIGS. 1-4 is to facilitate the contact between the solution, that is the nail infection agent, and the infected nail(s) N while minimizing the contact between skin S and the solution; and to provide a convenient, portable, and disposable, and/or reusable means to apply solution to the infected nails.
[0020] Treatment apparatus A includes a reservoir 1 which supplies sponge 5 with solution. Reservoir 1 may be designed as a container which supplies sponge 5 with solution via gravity feed through fluid tubing 3 , or (as illustrated in FIGS. 1 and 2 ) as an electronically controlled pump feed system through fluid tubing 3 , or as syringe feed through fluid tubing 3 . See Table A for an example of syringe feed which may be purchased as a commercial part. Although sponge 5 may be provided filled with solution, the use of some sort of solution reservoir permits sponge 5 to be supplied and re-supplied with solution as needed during a procedure.
[0021] Treatment apparatus A also includes an enclosure 21 which acts as the compress which holds all of the components together including pressing and keeping sponge 5 on top of the infected nail. Enclosure 21 is made of flexible, stretchy hook and loop type of material which adheres to itself similar to a diaper to fasten the invention around the toe(s), and to provide a thermal barrier between sodium acetate heater 4 and the outside. Enclosure 21 also acts to force heater 4 and sponge 5 against infected toe or finger nail(s) to provide an even distribution of both heat and solution and as a liquid barrier between the entire assembly and its surroundings. Enclosure 21 may be designed to accommodate only one nail or as many as ten.
[0022] Fluid tubing 3 is the conduit through which reservoir 1 supplies sponge 5 with solution. Corrosion resistant material choices for fluid tubing 3 include ETFE, PTFE, PFA, FEP, and Chemfluor. See Table A for an example of fluid tubing 3 available for purchase in ETFE material.
[0023] Sodium acetate heater 4 is a flexible plastic enclosure that contains sodium acetate disk and water. When the sodium acetate disk is clicked (fingernail tap) to mix with the water, the mixture changes to its solid state in an exothermic reaction to freeze at 130 F thereby heating the solution enclosed in sponge 5 . The process is reversible by boiling the solid back into the liquid state. Sodium acetate is a food additive and is non-toxic. An example of a sodium acetate heater that may be purchased as a commercial part is included in table A. Other types of heaters may be used and may also be affixed to reservoir 1 or between reservoir 1 and sponge 5 to perform the same function.
[0024] The purpose of sponge 5 is to absorb and saturate heated solution onto the infected nail(s), to maintain the solution on the surface of the nail, to isolate the surrounding skin from the solution as much as possible, and to apply heated solution to an irregularly shaped nail (not flat). Sponge 5 receives solution from reservoir 1 through tubing 3 . For this reason, sponge 5 may be made from a variety of absorbent sponge/cloth type materials, an example of which is included in Table A. It may be desired to use some type of seals surrounding sponge 5 to help prevent the heated solution from contacting the user's skin.
[0025] Sodium polyacrylate liner 21 is the liner between sponge 5 and heater 4 having the same outline as diaper enclosure 2 and may be made from a variety of sponge/cloth type materials (including sodium polyacrylate to absorb excess solution) an example of which is included in Table A. Sodium polyacrylate is the chemical in baby diapers to absorb moisture.
[0000] Intended Use of Preferred Embodiment
[0026] Treatment apparatus A creates a volume which contains and heats a solution around infected nail(s) to amplify the keratolytic properties of the solution to theoretically imbed the solution within the nail molecular structure, in addition to etching the nail from the top.
[0027] To use treatment apparatus A, infected nail(s) are wrapped into diaper enclosure 2 shown in FIGS. 1-3 , preferably creating a liquid tight seal, to force solution-saturated sponge 5 against the infected nail(s). The appropriate chemistry solution (see the discussed below) is added to reservoir 1 which fills sponge 5 with solution. The sodium acetate heater is clicked with a fingernail to heat the solution in sponge 5 . Solution is removed from sponge 5 using aspiration of reservoir 1 as necessary.
[0000] The Treatment Apparatus of Alternative Embodiment
[0028] Treatment apparatus B of FIGS. 5-7 includes a sponge 5 is to absorb and saturate heated solution onto the infected nail(s), to maintain the solution on the surface of the nail, to isolate the surrounding skin from the solution as much as possible, and to apply heated solution to an irregularly shaped nail (not flat). Sponge 5 receives solution from reservoir 1 through tubing 17 . For this reason, sponge 5 may be made from a variety of absorbent sponge/cloth type materials, an example of which is included in Table A. Sponge harness 20 is a frame which surrounds and captures sponge 5 for vertical adjustable mounting to threaded rods 15 .
[0029] The center of sponge harness 20 is open to allow sponge 5 to extend beyond sponge harness 20 to allow sponge 5 to contact the nail with solution. This design allows for vertical adjustment of sponge 5 and sponge harness 20 within enclosure 7 perpendicular to the nail to provide pressure between the nail plate and sponge 5 for thorough distribution of solution onto the nail. Likewise a variety of materials would be appropriate for sponge harness 20 , preferably corrosion resistant ones such as 316 L stainless steel or chemically resistant plastics as polycarbonate.
[0030] The design intent for fluid-containing, conformable heat transfer device 18 is to evenly distribute heat from the flat regular surface of heater plate 17 to the irregular surface of sponge 5 as it conforms to the irregular nail surface. Device 18 can be made from most flexible water tight plastics (see example in Table A) with a heat transfer fluid such as water trapped inside. The heat transfer fluid inside device 18 contacts the walls of its plastic enclosure and flows inside the plastic evenly distributing the heat from heater 4 and heater plate 17 to sponge 5 . The flexible plastic of device 18 is smoothed, hardened and flattened at its edges with holes added for vertical adjustment on threaded rods 15 .
[0031] Heater 4 is a standard flexible heater available from many suppliers and is usually made by embedding resistance wires inside a thermally flexible rubber material (see Table A) and its temperature is controlled with a heater controller such as item 11 or 12 . Heater 4 may be purchased with a pressure sensitive adhesive on one side to secure the heater and for a good thermal connection with heater plate 17 . Heater 4 may also be affixed to reservoir 1 to perform the same function.
[0032] Heater cover 19 is made from a high temperature thermally isolating material such as polyamide-imide. The center portion of heater cover 19 is scalloped so only the edges contact heater plate 17 to limit heat transfer even further. Heater cover 19 is designed to thermally isolate heater 4 from enclosure cover 8 . Heater cover 19 includes holes through which travel threaded rods 15 for vertical adjustment.
[0033] Toe harness 6 is designed to comfortably secure toes or fingers within enclosure 7 . Materials of choice for toe harness 6 include corrosion resistant metals such as 316 L stainless steel and plastics such as polycarbonate. Threaded rods 15 are permanently and perpendicularly fixed to toe harness 6 using an appropriate adhesive, sonic, solvent bond, or internal or external fastener, and do not move. Toe harness 6 is permanently attached to enclosure 7 using an appropriate fastener means as above and likewise does not move.
[0034] Enclosure 7 surrounds, thermally isolates, and preferably creates a liquid barrier between the entire assembly and its surroundings. Enclosure 7 should be made of a corrosion resistant metal such as 316 L stainless steel or plastic such as polycarbonate. Enclosure 7 includes an opening 22 for receipt of digit(s) D, that is the finger(s) or toe(s), with the infected nail(s). Enclosure components may be designed to accommodate only one digit or as many as ten.
[0035] Enclosure cover 8 further seals enclosure 7 and the entire assembly from its surroundings and may be made from a semi-high temperature semi-hard rubber material such as EPDM rubber (Shore A 60). Enclosure cover 8 does not move relative to enclosure 7 .
[0036] Hex nut 9 should be made from a corrosive resistant metal such as 316 L stainless steel to keep threads from galling (see Table A). When hex nut 9 is tightened on threaded rods 15 against enclosure cover 8 , it compresses springs 10 forcing heater 4 , heater plate 17 , fluid 18 , sponge 5 and sponge harness 20 against the infected toe nail(s) to provide an even distribution of both heat and solution to the nail(s).
[0037] Spring 10 should be made of 316 L stainless steel or other material to withstand both corrosion and repeated tension and compression. The design intent for spring 10 is to provide the spring tension force that compresses the above components into a good thermal and liquid contact with the infected nail(s) against enclosure cover 8 .
[0038] AC heater controller 11 regulates heater 4 (by modulating power from the wall outlet to heater 4 ) to selected temperatures. AC heater controller 11 is purchased as a commercial part as shown in Table A. Regulating the temperature in AC heater controller 11 also regulates the temperature of heater plate 17 , device 18 and sponge 5 . Sponge 5 controls the temperature of the solution on the infected nail which is optimized according to the selected treatment chemistry.
[0039] Battery heater controller 12 performs the same function as AC heater controller 11 , with the exception that it draws its power from battery pack 13 instead of the wall outlet and is purchased as a commercial component and modified to operate to use battery power instead of AC power. Battery heater controller 12 coupled with battery pack 13 enables the entire assembly to be portable.
[0040] Battery pack 13 supplies the power to operate the assembly when in portable mode and may be purchased from a supplier as shown in Table A. Battery pack 13 may be made from a variety of rechargeable battery technologies including NiMH, Lithium Ion, or a hydrogen fuel cell.
[0041] Leg harness 14 removeably attaches battery heater controller 12 and battery pack 13 to the limb for portable operation. Leg harness 14 may be made from a variety of materials including nylon fabric, leather, or plastic straps. See Table A for an example of a harness which may be purchased as a commercial part.
[0042] Reservoir 1 supplies sponge 5 with solution. Reservoir 1 may be made of a variety of corrosion resistant materials including polycarbonate and 316 L stainless steel. Reservoir 1 may be designed as a container which supplies sponge 5 and the above volumes with solution via gravity feed through fluid tubing 3 , or as an electronically controlled pump feed system through fluid tubing 3 , or as syringe feed through fluid tubing 3 . See Table A for an example of syringe feed which may be purchased as a commercial part.
[0043] Threaded rod 15 is the shaft on which the entire assembly travels in a vertical direction perpendicular to the nail. Threaded rod 15 should be made of corrosion resistant material such as 316 L stainless steel. See Table A for an example of a threaded rod which is available for purchase as a commercial component.
[0044] Fluid tubing 3 is the conduit through which reservoir 1 supplies sponge 5 and the volumes above with solution. Corrosion resistant material choices for fluid tubing 3 include ETFE, PTFE, PFA, FEP, and Chemfluor. See Table A for an example of fluid tubing 3 available for purchase in ETFE material.
[0045] Electrical wire 16 is subdivided into three groups 16 A, 16 B, and 16 C depending on the electrical connection. 16 A electrical wire designates the connection between heater 4 and AC heater controller 11 . 16 B designates the connection between battery pack 13 and battery heater controller 12 . 16 C designates the connection between AC heater controller 11 and the wall outlet. Electrical wire 16 (all groups) varies in diameter depending on the intended current it carries—an example of which (copper wire insulated with PTFE) is in Table A and is purchased as a commercial component.
[0046] Heater plate 17 is designed to support and evenly disburse heat from heater 4 (flexible heater with pressure sensitive adhesive on one side). Heater 4 should be made from a good thermally conductive material such as aluminum, which has been anodized (plated) to resist corrosion.
[0000] Intended Use for Alternative Embodiment
[0047] Treatment apparatus B creates a volume which contains and heats a solution around infected nail(s) to amplify the keratolytic properties of the solution to theoretically imbed the solution within the nail molecular structure, in addition to etching the nail from the top.
[0048] To use treatment apparatus B, infected nail(s) are inserted into enclosures shown in FIGS. 5-7 . All fasteners are tightened, preferably creating a liquid tight seal, to force saturated sponge 5 against the infected nail(s). The procedure is preferably continued for a therapeutically effective time period, typically about 20 to 30 minutes daily. The appropriate nail infection agent is added to reservoir 1 which fills sponge 5 and the appropriate volumes formed inside the enclosures with the agent.
[0049] For portable operation, battery pack 13 and battery heater controller 12 are strapped to the appropriate limb using leg harness 14 . Electrical connection 16 B is made between battery pack 13 and battery heater controller 12 . Electrical connection 16 A is also made between battery heater controller 12 and heater 4 . The appropriate temperature is selected by rotating the dial on the battery heater controller 12 . To remove the invention, the battery heater controller 12 is turned off. Solution is removed from the volumes using aspiration or gravity. Fasteners are loosened and the nail(s) are removed.
[0050] For stationary operation, heater controller 11 is plugged into a standard wall outlet using electrical connection 16 C. Electrical connection 16A is also made between heater controller 11 and heater 4 . The appropriate temperature is selected by rotating the dial on the heater controller 11 . To remove the invention, the heater controller 11 is turned off. The solution is removed from the volumes using aspiration or gravity. Fasteners are loosened and the nail(s) are removed.
[0000] Discussion of Typical Nail Infection Agents, Times and Temperatures
[0051] The terms tinea unguium and onychomycosis specifically refer to fungal infections of the toe nails. These infections, however, may be caused by different fungi such as: Trichophyton rubrum and Trichophyton mentagrophytes, which are the major two.
[0052] Most successful antifungal agents such as ciclopirox and Anacor AN2690 are broadband antifungal agents which means they are effective in treating a wide range of fungi responsible for onychomycosis.
[0053] However, even a broad band antifungal agent is ineffective in treating onychomycosis without contacting the fungus. To facilitate this contact, the antifungal agent (and a keratolytic agent such as salicylic acid) are dissolved in warm water (45 degrees C.).
[0054] The infected nails are submerged in the warm solution mixture for 20 to 30 minutes daily. Since human nails are made of keratin, and keratin absorbs water, the antifungal agent becomes embedded inside the nail, contacting the fungus.
[0055] Additional topical treatments (such as a topical antibiotic ointment over undecyclenic acid) are applied after the water has evaporated to further create a toxic environment for the fungi.
TABLE A ITEM NO DESCRIPTION QUANTITY MFG/SUPPLIER REF PART NO 1 Reservoir 1 mcmaster.com 7510A656 2 Diaper Enclosure 1 mcmaster.com 58435T11 3 Fluid Tubing A/R mcmaster.com 50375K41 4 Heater 1 mcmaster.com 35765K126 5 Sponge 1 mcmaster.com 7271T32 6 Toe Harness 1 custom N/A 7 Enclosure 1 custom N/A 8 Enclosure Cover 1 custom N/A 9 Hex Nut 4 mcmaster.com 90730A003 10 Spring 4 mcmaster.com 9657K81 11 AC Heater Controller 1 mcmaster.com 35655K89 12 Battery Heater Controller 1 mcmaster.com/ mod of custom 35655K89 13 Battery Pack 1 sears.com 911022000 14 Leg Harness 1 mcmaster.com 8062T211 15 Threaded Rod 4 mcmaster.com 93250A105 16 Electrical Wire A/R mcmaster.com 1749T23 17 Heater Plate 1 custom N/A 18 Heat Transfer Device 1 mcmaster.com 7789A11 19 Heater Cover 1 custom N/A 20 Sponge Harness 1 custom N/A 21 Sodium Polyacrylate 1 mcmaster.com 7271T32 Liner 22 Opening 1 custom N/A
[0056] The above descriptions may have used terms such as above, below, top, bottom, over, under, et cetera. These terms are used to aid understanding of the invention are not used in a limiting sense.
[0057] While the present invention is disclosed by reference to the preferred embodiments and examples detailed above, it is to be understood that these examples are intended in an illustrative rather than in a limiting sense. It is contemplated that modifications and combinations will occur to those skilled in the art, which modifications and combinations will be within the spirit of the invention and the scope of the following claims.
[0058] Any and all patents, patent applications and printed publications referred to above are incorporated by reference. | An infected nail of a digit of a patient is treated using apparatus including an enclosure capable of housing at least a distal end of at least one digit of a patient having an infected nail. The apparatus also includes a heater and a nail infection agent-containing member housed within the enclosure and positionable against an infected nail at the distal end of a digit housed within the enclosure. The heater is in heat-transfer relationship with the nail infection agent. In this way heated nail infection agent can be maintained against an infected nail by the nail infection agent-containing member. | 0 |
FIELD OF THE INVENTION
[0001] The invention relates to methods for winding layered structures. The invention relates particularly to methods for winding structures comprised of discrete layers.
BACKGROUND OF THE INVENTION
[0002] Wound layered structures are known in the technological arts. Wound structures, such as rolls of paper materials, composite wound paper laminates, wound nonwoven structures, and wound electrode structures are well known.
[0003] One limitation relating to winding structures is the speed at which the winding occurs. Winding systems may be limited by the maximum speed at which a structure may effectively be wound. This speed may be lower than the speed at which individual components of the wound structure may be transported and provided to a winding station.
[0004] Some structures comprise material components which are sensitive to mechanical handling issues. These materials may require winding systems which minimize or eliminate any handling operations which subject the materials to tensile forces.
[0005] What is desired is a method and apparatus for winding a structure where the winding speed is decoupled from the material transport speed. The structure may be comprised of multiple discrete layers, or of a single layer. The method and apparatus may wind structures while subjecting component elements of the structure to little, if any tensile forces.
SUMMARY OF THE INVENTION
[0006] In one aspect a winding apparatus comprising a rotating winding drum, a lay down station, a cutting station, a web assembly hold down element and a wound assembly discharge station. The rotating winding drum further comprises a plurality of winding stations. Each winding station comprising a winding mandrel, a winding nip, a web stabilizing bed and a cutting anvil.
[0007] In one aspect, a winding method comprising steps of: rotating the winding drum; transferring a first web structure from a first lay down station to the web stabilizing bed of a first winding station; cutting the web structure; contacting the web structure with the web assembly hold down element, winding the web structure into a roll assembly; and discharging the roll assembly from the winding drum.
[0008] In one aspect, a winding method comprising steps of: rotating the winding drum; transferring a first web from a first lay down station to the web stabilizing bed of a first winding station; transferring a second web from a second lay down station to a face-to-face position with the first web upon the web stabilizing bed of the first winding station; cutting the second web; contacting the second web with the web assembly hold down element, winding the assembled webs into a layered roll assembly; and discharging the layered roll assembly from the winding drum.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1 schematically illustrates a side view of one embodiment of the apparatus of invention.
[0010] FIG. 2 schematically illustrates a cross-section of a portion of the side view of a winding station of one embodiment of the invention.
[0011] FIG. 3 schematically illustrates a side view of a portion of an embodiment of the invention.
[0012] FIG. 4 schematically illustrates a side view of a portion of an embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0013] A winding apparatus comprises a winding drum. The winding drum may generally comprise a cylinder arrayed substantially symmetrically about a central axis. The winding drum may be configured to rotate about the central axis. The rotation of the winding drum may be continuous or intermittent. The winding drum may be considered to be comprised of a collection of circumferences. Each winding drum circumference may rotate about the central axis. Each circumferential point may be defined as lying in a plane of rotation. The respective planes of rotation lying perpendicular to the central axis of the winding drum. The rotation of the winding drum about the central axis causes each point of the circumference of the winding drum to define a circle centered upon the central axis and lying in a plane of rotation. The winding drum comprises at least one winding station. The winding station comprises a mandrel drive element and a winding nip element.
[0014] In one embodiment the mandrel drive element may be coupled to a winding mandrel and may rotate the mandrel to wind the structure. The mandrel may comprise a split mandrel of at least two parts which may be moved laterally independent of each other. The split mandrel may mechanically capture at least one web element to facilitate winding the structure. Alternatively, the mandrel may be a single element and may be coupled to the web using static electricity, adhesive, vacuum, or other coupling means as are known in the art. A single mandrel may be a solid or hollow core element.
[0015] In one embodiment the mandrel may be comprised of a frangible series of joined elements which may be individually separated and may each become part of the individual wound structures. Such mandrels may be comprised of paper stock, polymer, metal, wood or other materials as necessary for desired properties of the finished structures.
[0016] The mandrel may comprise a particular cross sectional shape transverse to the mandrel rotation. The shape of the mandrel relates to the shape of the wound structure. A round cross section yields a round structure. Similarly, an oval elliptical rectangular or square cross section each leads to a similarly shaped wound structure. The corners of a rectangular, squares or other regular polygon cross section may be sharp or broken depending upon the particular web materials being wound and the desired final shape of the wound structure.
[0017] The mandrel drive element may be driven by a local drive motor which is direct coupled to the element, or which is coupled to the mandrel drive element via a chain, belt or gear system, or a combination of these.
[0018] In one embodiment the mandrel drive element may be driven and may comprise a sheave or pulley coupled to a mandrel and disposed such that the mandrel drive element tangentially contacts a driven belt which is external to the winding drum. In this embodiment, the mandrel drive element and the mandrel will be driven while in contact with the moving belt. In this embodiment, the mandrel drive element will not be driven when not in contact with the belt and when the belt is not moving.
[0019] This configuration may be utilized for an apparatus comprising a plurality of winding stations, each comprising a mandrel drive element. The plurality of stations may be arrayed along the circumference of the winding drum. As the drum rotates, each mandrel drive element may sequentially be brought into contact with a driven belt over a portion of each rotation of the winding drum. In this manner, each mandrel drive element may be powered or driven over a particular segment of each rotation of the winding drum with a single common drive belt.
[0020] The radial position of the mandrel drive element with respect to the central axis of the winding drum may be fixed, or the radial position of the mandrel drive element may vary according to a predetermined path. In one embodiment the mandrel drive element may comprise a cam follower moving along a fixed cam as the winding drum and mandrel dive element rotate around the central axis of the winding drum. In this embodiment, the radial position of the mandrel drive element may vary in a regular manner over the course of a rotation of the winding drum. This regular progression may be used to accommodate the growth in the radial dimension of the wound structure as winding progresses. Moving the mandrel drive element along a radius may enable the outer circumference of the wound structure to maintain a substantially fixed radial position with respect to the central axis of the drum even as the structure is wound and increases in size.
[0021] In one embodiment the winding apparatus comprises single web lay down station. The web lay down station may comprise a pick and place system for providing a portion of a web material for winding into the wound structure. In this embodiment, the web material may be made available at a location that is not tangential to any circumference of the winding drum. The web may be picked from a staging area and placed upon the circumference of the winding drum.
[0022] In an alternative embodiment, the web lay down may be a rotary web lay down comprising a rotating drum having a tangential contact with a circumference of the winding drum. In this embodiment, continuous or discrete web portions may be disposed from the rotary web lay down to a circumference of the winding drum. The transfer of discrete web portions to the winding drum may comprise the step of altering the pitch or spacing and timing of the web portion between the delivery of the web portion from the web supply and the transfer of the web portion to the winding drum circumference.
[0023] The winding apparatus may also comprise one, or a plurality of web lay down stations. Any combination of pick and place, rotary, manual, and other web transfer mechanisms as are known in the art may be used to transfer web portions to the circumference of the winding drum.
[0024] Discrete web portions which are transferred to the winding drum may in turn comprise a number of discrete elements combined to comprise a more elaborate web structure. In one embodiment a conductive tab may be fixedly adhered to a web portion using adhesive, tapes, welds or other fastening means to provide the combination of the base web and the conductive tab for deployment to the winding drum.
[0025] The web materials laid down upon the circumference of the winding drum may be captured by the mandrel as described above. A split mandrel may be used to mechanically capture the web with each of two portions of the mandrel on either side of the web. In this configuration, the web will move and wind about the mandrel as the mandrel rotates.
[0026] The winding station further comprises a winding nip element. The winding nip element forms a pressure nip point together with the mandrel. The web materials pass through the nip as winding occurs. The winding nip element may comprise a substantially rigid or compliant material. It may be fixed or may rotate. The rotating winding nip element may be driven independently from the motion of the web or may move in response to the passage of the web materials through the nip. The winding nip element may be biased against the mandrel. The bias may be provided by the use of a spring to hold the winding nip element against the mandrel and the wound structure. The winding nip element may also be biased using any mechanical system known for such a use such as, but not limited to, cams and cam followers, air or hydraulic cylinders, rack and pinion gear systems and combinations of these systems.
[0027] A discrete web may be laid upon the winding drum such that the leading edge of the web coincides with the location of the mandrel of the winding station. Alternatively, the discrete web may be disposed up rotation from the mandrel and subsequently attached to a second web disposed upon the winding drum and also upon the discrete web. This second web may be disposed with a leading edge coinciding with the location of the mandrel or the second web may comprise a continuous web. A continuous web disposed upon the winding drum may overlay the first discrete web and winding mandrel location. The continuous web may be separated into discrete portions subsequent to being disposed upon the winding drum. This separation of the continuous web may occur after that portion of the continuous web coinciding with the location of a particular winding station mandrel has been captured by the mandrel.
[0028] The winding apparatus may comprise a web separating element. The web separating element may comprise a portion of the lay down station, each winding station may comprise a web separating element, the web separating element may comprise a system of elements including an element of each winding station acting in cooperation with an element external to the winding drum to cause web separation. The web separating element may comprise a cutting anvil as part of the winding station acting in cooperation with a cutting element. The cutting element may comprise one or more knives disposed upon the outer circumference of a cutting drum. The size of the cutting drum, the spacing of the knives and the rotational speed of the cutting drum relative to the winding drum may be configured to bring a knife into the proximity of the web material and the cutting anvil of the winding station such that the web material is separated. The separation may be due to a cut caused by interference between the path of the knife and the path of the upper surface of the anvil. The separation may be a burst separation due to an open nip between the knife and anvil sufficiently small to burst the intervening web material. The separation may be accomplished using one or more cutting wires configured to interact with the web material and to cause separation by heating thermoplastic web material until separation occurs. A pulsed or reciprocating laser may be configured to separate the web material. A rotary or reciprocating saw may be configured to move in concert with the web material as it traverses the width of the web material to cause web separation.
[0029] Separation of the web material yields a tail end and a leading end, or edge, of the respective portions of the web material. The leading end may be captured by the mandrel as described prior to web separation. Control of the leading end is thereby maintained as the winding process progresses. At least a portion of the web material between the leading edge and the tail edge may be under the influence of the stabilizing element (described below) prior to the web separating event. Control of the web materials tail end is thereby enhanced.
[0030] Continuous web materials may be transferred to the winding drum using a rotary web transfer system as is known in the art. The continuous web material may follow a web path around a transfer drum to a position upon the circumference of the winding drum.
[0031] The sequence of laying down a discrete web, laying down a continuous web upon the discrete web and attaching the two webs, capturing the continuous web with the mandrel, separating portions of the continuous web, winding the stack of attached webs into a wound structure while stabilizing the stack between the winding drum and stabilizing element illustrates one method of utilizing the apparatus. The stack may also comprise additional discrete and or continuous web portions provided by additional lay down stations as described.
[0032] In one embodiment a series of first web structures each comprising a combination of discrete and continuous webs are laid down as the winding drum proceeds through each rotation. The structures are individually wound as the winding mandrels pass beneath the stabilizing element such that the structures are provided lateral stability relative to the central axis during winding.
[0033] In one embodiment a first discrete web material is laid down followed directly by a first continuous web material, a second discrete web material and a second continuous web material to form a series of four-web stacks as the winding drum proceeds through each rotation. The stacks are individually wound as the winding mandrels pass beneath the stabilizing element such that the stacks are provided lateral stability relative to the central axis during winding.
[0034] The web materials are transferred from the lay down element to a circumferential surface of the winding drum. The circumferential surface may comprise a web guide track. In one embodiment the web guide track comprises a web transfer or support surface disposed along the circumference of the winding drum at a first radius from the central axis of the drum. The transfer surface comprises a surface having a dimension transverse to the rotation of the drum equal to or greater than the transverse dimension of the web material in a single web structure or the first web material transferred to the winding drum in a multiple web structure.
[0035] The web guide track may also comprise one or more apertures operatively connected to a low pressure or vacuum source. The first web material may be subjected to a low pressure or vacuum to reduce the likelihood of the web material shifting in position after it has been laid down and prior to winding. As the winding step for any particular station commences, the application of the low pressure or vacuum to the first web may be gradually or abruptly ceased. In one embodiment, the application of the low pressure/vacuum may be constrained to follow the tail end of the web material as it is wound. In this embodiment, the winding drum interior is segmented for each winding station. The segments each comprise an operable connection to a low pressure or vacuum source and each segment comprises a movable segment wall configured to move toward a fixed segment wall as the winding sequence progresses and to retrace its path to an initial position prior to the transfer of the first web of the next revolution of the winding drum. The motion of the movable segment wall may be accomplished using a cam follower and cam, a rack and pinion, rotary or linear actuators or other means as are known in the mechanical arts.
[0036] The transverse cross section of the transfer surface may be substantially parallel to the central axis of the winding drum, or the cross section may be biased with respect to the central axis. Providing a biased surface may subject the web materials to desirable forces transverse to the direction of drum rotation during the web transfer and winding operations.
[0037] The cross section of the web guide track may include one or more steps. The steps may provide additional support surfaces for subsequent web materials in a multiple web structure. The steps may be separated radially by one or more guide track edge elements. Web guide track edge elements and steps may be disposed along a single edge of the transfer surface or along both edges of the transverse cross section of the surface. The web guide track may comprise a first surface and a series of steps along one edge together with a single edge element along the other edge or a height corresponding at least to that of the series of steps.
[0038] In one embodiment the initial web material is disposed in the bottom of the web guide track and substantially fills the portion of the guide track between the lower track surface and the first step surface. A second web is deposited upon the drum in the web guide track and upon the first web. In one embodiment, the second web has an axial width greater than that of the first web and the second web substantially fills the portion of the web guide track between the first step and a second step. In one embodiment the first and second web materials may be stacked in the space between first track edge elements with none of the first or second web material protruding above the first step of the track. In another embodiment, a portion of the second web may protrude above the first step on one or both edges of the track. In this embodiment, a third web material may be stacked upon the second web material. The protrusion of the second web upon one or more steps may physically separate the first and third webs. Additional web materials may subsequently be disposed upon the three web stack along the web guide track.
[0039] During the step of winding the structure from the web stack, it is possible to subject the web stack to lateral forces which vary across the transverse—or axial-dimension of the web. Web materials subjected to these varying forces may undergo a lateral position shift if not constrained. The cross section of the web guide track may provide lateral stability to the web stack as the stack proceeds along the web guide track during the winding step.
[0040] One or more stabilizing elements may be present to provide additional stability in the transport of the web after the web has been disposed upon web guide track of the circumference of the winding drum. The stabilizing element may comprise fixed or rotating elements.
[0041] One or more rollers may be used to assist in stabilizing the position of the web or webs upon the winding drum. The roller(s) may be disposed relative to a circumference of the winding drum to provide a zero clearance nip with the drum, an open nip, or an interference nip wherein the roller, the drum, or both are subject to compression.
[0042] A stationery element such as compliant foam, sponge or brush may be used to stabilize the web materials after lay down has occurred. The stabilizing element may extend along a segment of the circumference of the winding drum. The position of the stabilizing element may be fixed relative to the rotation of the drum such that the rotation of the drum will cause the circumference of the drum to pass the stabilizing element during each revolution.
[0043] The stabilizing element may extend along the circumference of the winding drum such that the web materials are disposed between the element and the drum circumference as the materials are wound via the rotation of the mandrel.
[0044] The stabilizing element may be disposed to provide no clearance between the element and the circumference of the drum. The stabilizing element may be placed under a compressive load or may be placed such that there is no clearance without compressively loading the stabilizing element, rotating drum and the stabilizing element. Alternatively, the stabilizing element may be disposed to provide a gap between the element and the winding drum. The gap may be identical to the nominal thickness of the web materials handled by the winding apparatus of the gap may be smaller than this thickness to provide the desired degree of loading of the web materials as the winding drum rotates past the stabilizing element.
[0045] The stabilizing element may comprise a cross section transverse to the direction of rotation of the winding drum substantially identical to the cross section of the web guide track. Alternatively, the stabilizing element may comprise a cross section distinct from that of the web guide track. The stabilizing element may be subject to compression as described above and may conform to the cross section of the web guide track and/or the web guide track—web combination.
[0046] The winding apparatus further comprises a wound structure tail fixing station. The tail fixing station facilitates securing the outer wrap of the wound web materials to the remainder of the structure. The station may perform this function via the application of an adhesive laminate outer wrap to the circumference of the wound structure. The axial width (the dimension of the material parallel to the central axis of the winding drum during application) of such an outer wrap may be coextensive with the axial width of the wound structure or the outer wrap may be either larger or smaller than the axial width of the structure. A plurality of outer wraps may be applied to the wound structure. The length of the outer wrap may be greater than the circumference of the wound structure to ensure that the tail portions of the web materials are completely secured.
[0047] In an embodiment where the angular position of the web material tails are known, such as where each mandrel is coupled to an angular position resolver, the length of the outer wrap may be less than the circumference of the wound structure and the placement of the outer wrap may be controlled such that tail of the web materials are secured to the remainder of the wound structure. The station may secure the web material tails using an elastic band disposed around the circumference of the wound structure, by applying a fixative coating to the structure, by positioning a heat-shrink sleeve and subsequently applying the heat necessary to shrink the sleeve or using other fixative means as are known in the art.
[0048] The tail fixing station is disposed with a tangential contact to the winding drum at a circumferential location between the stabilizing element and the first lay down station considered in the direction of rotation of the winding drum.
[0049] The winding apparatus further comprises a discharge station for transferring the wound structures from the drum. This station is disposed between the tail fixing station and the first lay down station considered in the direction of rotation of the winding drum. The discharge station comprises a removal element which, in turn, may comprise a pick and place assembly to pick the wound structure from the winding drum and place it in a holding assembly or transfer the structure directly to a conveying system for further handling.
[0050] In one embodiment the removal element comprises a moving belt having tangential contact with the winding drum circumference. The belt may comprise one or more cavities and may be configured to open and close the cavities such that the open cavity contacts the wound structure and subsequently closes capturing the structure and carrying it away from the winding drum along the path of the belt. The belt may comprise a seamed or seamless belt or a series of belt links flexibly joined together. The belt may be disposed adjacent to a vacuum plenum (which in turn is operatively connected to a vacuum source) such that a negative air pressure may be used in capturing and/or holding the wound structure for removal from the winding drum.
Web Description:
[0051] The web materials wound by the apparatus may comprise simple homogeneous materials or more complex composite structures comprised of numerous elements. The web materials may be provided as discrete elements or as a continuous web which is separated into individual segments. The web materials may comprise paper, metal, polymers and combinations thereof. The web materials may comprise films, non-wovens, foils, woven structures and combinations thereof.
Winding Methods:
[0052] The following examples provide non-limiting methods of using the above described apparatus. The description is provided in terms of the steps which occur at a single winding station. The same sequence of steps may be performed concurrently at a plurality of winding stations spaced circumferentially around the drum. The rotation of the winding drum moves each station through 360 degrees of rotation. As each station progresses through each rotation, winding steps may be executed relative to the station. The winding steps may be associated with particular segments of the rotation. As an example, a particular step may occur as the winding station moves through the first 45 degrees of the 360 degrees.
[0053] In one embodiment the winding drum is continuously rotated about the central drum axis. As a winding station progresses through a first segment of the rotation, a first web material is transferred from a first lay down station to the winding station. A second web material is transferred from a second lay down station to a position adjacent to the first web material and in a face-to-face relationship with the first web material. The first and second web materials form a web assembly.
[0054] A winding mandrel contacts and attaches to the web assembly. The rotation of the winding drum brings the second web material into contact with a web stabilizing element. After the web stabilizing element contacts the web assembly, the mandrel rotates to wind the assembly. The rotation of the winding mandrel draws the web assembly forward in the direction of the travel of the winding drum. The web assembly is wound upon itself between the winding mandrel and a winding nip element. The winding nip element provides a tension in the web assembly and reduces the likelihood of wrinkles in the webs as the wound structure is formed.
[0055] As or after the winding of the web assembly is completed, the tails of the first and second web materials are fixed to reduce the possibility of the wound assembly unwinding. The rotation of the drum moves the winding station to a position where the wound assembly with the fixed tails is discharged from the winding apparatus. In one embodiment, one of the first or second web materials is provided as a continuous web material. As or after the leading edge of the web material is transferred to the winding drum, a portion of the web material is separated to facilitate the winding of the web assembly. The separation may occur as part of the web lay down such that the web is discrete as transferred to the winding drum. In one embodiment the separation may occur after the entire portion of the web material to be incorporated into the web assembly has been transferred. In this embodiment, the separation yields a leading and trailing edge of the web material upon the circumference of the winding drum.
[0056] In one embodiment a plurality of winding station spaced about a circumference of the winding drum each perform the enumerated steps as the winding drum rotates about the central axis.
[0057] In one embodiment the first and second web materials may be at least partially attached to each other prior to winding the web assembly. In this embodiment, the leading edges of the two web may be attached or the leading edge of one web may be attached to any portion of the other web. The attachment may be accomplished using an adhesive, a cohesive, by welding the materials or by otherwise bonding the web materials to each other.
[0058] In one embodiment the tails of the web assembly may be fixed by overwrapping the wound assembly with a portion of adhesive tape. The axial width of the tape may be equal to the widest axial dimension of the wound assembly or the axial widths may be distinct from each other. The tape may be applied without regard to the angular position of the tail ends and the tape may be applied over more than 360 degrees of wrap around the assembly. In one embodiment the tape may be applied in registration with the angular position of the tails and may be sized to overwrap the tail ends plus a predetermined amount of the circumference of the wound assembly which is less than the full circumference of the assembly.
[0059] In one embodiment the web materials are transferred to a web guide track upon a circumference of the winding drum. The web guide track may comprise a simple track having a single edge or a more complex track as asset forth above.
[0060] In one embodiment a third web material may be laid down in a face to face relationship with the web assembly of the first and second webs prior to winding. The new three web assembly may subsequently be wound as described above.
Example
[0061] As shown in FIG. 1 , the winding drum 100 comprises a plurality of winding stations 110 . Each winding station 110 comprises a mandrel drive element 112 and, The winding drum 100 is disposed adjacent to a plurality of web lay down stations 200 . Each web lay down station 200 comprises a rotary lay down drum. Web separating element 710 is disposed adjacent to the winding drum 100 . Web assembly hold down element 300 is also disposed adjacent to the winding drum 100 . The web assembly hold down element 300 may comprise a compliant element or a plurality of rolling elements. The rolling elements may be comprised of a rigid or a compliant material. The wound assembly discharge station 500 is disposed adjacent to the winding drum 100 and comprises the wound assembly removal element.
[0062] As shown in FIG. 2 , the web guide track 120 comprises web transfer surface 122 , first web guide track edge element 124 and second web guide track edge element 126 . Web assembly hold down element 300 is disposed adjacent to the web transfer surface. Also shown in the figure are a first 10 , second 12 , third 14 and fourth 16 web materials disposed in the web guide track 120 upon the web transfer surface 122 .
[0063] As shown in FIG. 3 , winding nip element 114 is disposed adjacent to the winding mandrel 130 . The web separation station 700 is disposed on a circumference of winding drum 100 in the direction of travel of the winding drum 100 from the winding station 110 .
[0064] As shown in FIG. 4 , winding station drive element 600 is disposed adjacent to mandrel drive elements 112 . The winding station drive element in the figure comprises a driven belt 610 , a drive assembly 620 and belt tensioning element 630 . The belt 610 is disposed to maintain contact with the mandrel drive elements 112 over a portion of each rotation of the winding drum 100 to enable winding the wound assemblies as the winding stations 100 pass through that portion of each rotation.
[0065] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.” Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
[0066] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. | A winding method includes rotating a winding drum; transferring a first web structure from a first lay down station to the web stabilizing bed of a first winding station; cutting the web structure; contacting the web structure with a web assembly hold down element, winding the web structure into a roll assembly; and discharging the roll assembly from the winding drum. | 1 |
BACKGROUND OF THE INVENTION
The invention relates to a method for dissolving the bond between interconnected (nested). components which, together with a plastic layer which bonds them together, form a compound system. The method effects configurational changes in the system. The invention moreover relates to an apparatus for performing the method.
Compound systems of structural components which are nested together with the aid of a cement-like plastic layer (hereafter also referred to as "synthetic material") are used in many technological fields, provided that the surfaces of the components can be so designed that the connecting plastic can effect a form-locking connection with these parts. In particular, such techniques are used for components which cannot be connected in any other manner since they are in accessible, for example, either to welding or riveting. In most cases the components are of unlike materials.
A very significant field of application for such compound systems is the field of endoprostheses which is concerned with the connection of members of a living organism with artificial prostheses. In surgical operations on bones or joints, a bone cement (e.g. a methylmethacrylate) is used to fix alloplastic substitute joints, for compound osteosyntheses, for example, in the field of neurosurgery for dorsal cervical vertebra reinforcements and for cranial replacements. The bone cement connects the metallic or nonmetallic implant with the bone by way of clamping profiles on the prosthesis on the one hand to roughnesses and protrusions on the bone on the other hand.
In many cases it is necessary to exchange or align an endoprosthesis. The procedure of exchanging the endoprosthesis is effected by first exposing the joint in question. Then the prosthesis and which generally still resists mechanical removal - although it might have already become loosened to the point of being painful - is freed of surrounding bone cement by reshaping the bone, if necessary, whereupon a new prosthesis is implanted with bone cement. In alloplastic surgery on joints it is the practice to remove as little bone as possible when implanting a prosthesis and to encase the prosthesis in as much bone and soft tissue as possible so that only the functionally required part remains exposed. The entire anchoring is generally effected in a closed cylindrical (tubular) bone. Thus, this bone must remain intact as much as possible when the prosthesis to be exchanged is removed so as to permit implantation of a new prosthesis. This involves the difficulty that the bone cement must be removed from very narrow gaps, sometimes only a few millimeters in width, by means of long special chisels, cutters and drills. Often it is necessary to fenestrate the bone at locations more remote from the joint. Only after the endoprosthesis connection has been freed sufficiently from the cement-like plastic layer can the prosthesis be tapped out and the operation be continued. After removal of the endoprosthesis, the surgical field becomes larger and any residual bone cement still remaining in the marrow cavity can be removed with chisels, cutters and drills or by screwing cement parts to thread cutters and knocking them out. If necessary, the bone is reshaped and then a new endoprosthesis is implanted with bone cement.
Compound osteosyntheses are bone reconstructions involving a combination of plates, nails, wires, screws and bone cement. Such surgical procedure is relied upon for bone fractures where mere reconstruction by means of the above-described metal parts is insufficient and it is necessary to additionally support the bone by means of bone cement. In the neurosurgical field, reinforcements are employed particularly for the cervical vertebrae if there is a threat of slippage of the vertebrae with respect to one another and thus there is a danger of damage to the spinal cord. The prothesis of the vertebrae are tied together with wires, the cavities between the prothesis and the wires are filled with bone cement. In principle, this is a compound osteosynthesis. Parts of the cranium are replaced by cement-like plastics. After insertion of the replacements to be implanted, it is necessary to conform the shape of the surrounding area with mechanical tools. In order to permit tissue outside the artificial cranium to grow together with tissue inside it, the artificial cranium must be perforated at numerous places. Additionally it is possible to neurosurgically replace a vertebra by means of bone cement. However, there exists no satisfactory stabilization between the individual artificial vertebrae and between the artificial vertebrae and the remaining healthy vertebrae.
Exchanging or aligning an endoprosthesis is generally a complicated and very time consuming procedure. The difficulty resides in the fact that during removal of the endoprosthesis the bone should not be injured. Even with the greatest of care bone is often damaged and thus the secure seat of the new endoprosthesis is endangered and reconstructive measures may become necessary. Intentionally applied bone fenestrations may weaken the bone to a degree which is no longer justifiable.
Exchange operations are time consuming and may require many hours. The stress from anesthesia is considerable, particularly since the patients are usually old. During the long surgical procedure the loss of a considerable amount of blood from the marrow cavity cannot be prevented. Blood transfusions up to 5 liters are no rarity. This may produce grave postoperative complications and, for example, coagulation problems in the patient which then constitute a mortal danger. The great loss and transfusion of blood and the long operating times in these operations which require very large personnel are a considerable cost factor.
Dorsal reinforcements performed in neurosurgery on cervical vertebrae sometimes require correction. The connecting parts, bone cement and wires, may come loose or break, or the reinforcement may have to be extended to further sections of the spinal column. In such an operation, the previously applied wire and bone cement must be removed. The removal with mechanical tools, such as chisels, cutters and drills is again time consuming and, particularly in the immediate vicinity of the spinal cord, dangerous because of resulting jarring or the possibility of one of the tools slipping.
Cranial replacements of plastic must be reshaped once the plastic has hardened and has been implanted. This process is very time consuming when conventional tools are employed. Jarring may endanger the firm seat of the implant.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve a process and an apparatus of the above-mentioned type so that working on the cement-like plastic layer between the two nested components is substantially simplified without damaging the components or changing their composition.
This is accomplished by the present invention by effecting changes in shape with the aid of vibrations in the ultrasonic range.
The influence of ultrasound makes the synthetic material plastic in the boundary layer adjoining the object excited with ultrasonic waves so that the object can be moved from its position with respect to the synthetic material, whereby changes in shape are made in the cement-like synthetic material. The latter is worked with the aid of ultrasound so that it can be removed from the interstice between the nested components. This application of the invention is particularly useful in surgical procedures as outlined above. The described operations on bones and joints are substantially simplified. The probability of a far-reaching protection of tissues to be preserved - particularly the bone - increases considerably. The risk during the exchange of alloplastic substitute joints is reduced since renewed secure support and anchoring of the new implant is assured if the bone substance is essentially protected during the removal of the old implant. Moreover, the length of the operations is reduced considerably because the removal of bone cement with the aid of ultrasonically excited tools can be accelerated considerably. This eliminates long periods of anesthesia which, as noted before, could endanger the patient. Moreover, the patient is protected in that heavy blood losses are avoided. Shortening the time of the operation also has a saving influence on the costs for personnel and materials.
According to a preferred embodiment of the invention, an apparatus for practicing the method is designed as an ultrasonically excited tool which has a shape that enhances changes in shape of the compound system. With such design it is assured that at the tip of the tool a great amount of energy is available which serves to loosen the synthetic material and which, due to the special design of the tool, can easily be transmitted to such material to change it in the desired manner. Thus the tool can penetrate quickly into the synthetic material without the user of the tool having to exert considerable forces. Then the material is removed so that the components can be separated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an ultrasonic device with connected sonotrode;
FIG. 2 is a side view of a tool designed as a scraper;
FIG. 3 is a side view of a chisel;
FIG. 4 is a side view of a hollow tool;
FIG. 5 is a sectional view of a connection of two components by means of plastic; and
FIG. 6 is a perspective view of a profiled tool.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method according to the invention is based on the recognition that a great number of thermoplastic materials, for example polymethylmethacrylate, are heated locally in the boundary layer between the tool and the plastic when being worked with tools that vibrate in the ultrasonic range. As a result of the heating, the plastic melts and thereafter hardens again. During the plastic intermediate phase the object which has been excited in the ultrasonic range, for example the tool, changes its position with respect to the plastic and thus has a form-changing influence on the plastic. For example, if a component embedded in the plastic layer is excited in the ultrasonic range, the boundary layer of the component melts, so that the position of the component can be changed as long as the boundary layer remains plastic due to the excitation of the component. The component thus can be taken out of the plastic layer.
If instead of the component an ultrasonically excited tool is introduced into the synthetic layer, the tool penetrates into the plastic or liquid boundary layer formed between the synthetic material and the tool as a result of the ultrasonic excitation of the tool. The tool prevents the plastic from repolymerizing after the excitation has been discontinued. In this way, the tool makes a path for itself through the plastic material so that the latter is, by the path, separated into several parts. After the tool has worked several paths in the plastic, the pieces of plastic disposed between the paths can be removed from the interstice 3 disposed between components 1, 2 (FIG. 5).
A similar procedure is employed if in a medical case, for example, an endoprosthesis must be exchanged. It would be conceivable in this case to connect the prosthesis, which can be perceived as the internal component 2, directly with a sonotrode 6 of an ultrasonic device 5. In this case it is important to provide as rigid a connection as possible between the sonotrode 6 generating the ultrasonic vibrations and the endoprosthesis so that the largest amount of vibratory energy possible is introduced into the endoprosthesis by the sonotrode 6. This connection may be established, for example, with the aid of a screw connection 7 which is provided at the tip of the sonotrode 6. The screw connection 7 is screwed to a shaft 8 which is provided with a corresponding thread. It is also possible to employ a sleeve nut. Moreover, any other rigid connection between the sonotrode 6 and the prosthesis to be loosened is possible. A similar connection may additionally be provided for coupling other tools to the sonotrode 6.
By exciting the endoprosthesis in the ultrasonic range, the boundary layer of the plastic layer 4 melts along the interfaces with the shaft protruding into the plastic layer 4. In this state the endoprosthesis 2 can be removed from the cavity of the bone 1.
The endoprosthesis may also be removed from the tubular bone by completely removing the plastic layer 4 surrounding the endoprosthesis. For this purpose, another tool is placed onto the sonotrode 6 with the aid of which the bone cement, formed as the plastic layer 4, is removed from the interstice 3. Such a tool may be, for example, a chisel 12 (FIG. 3) which may be provided with a shaft 8 at its end facing the sonotrode 6. At its opposite end a cutting head 13 with a cutting edge 14 is provided which penetrates into the bone cement when the chisel 12 is excited in the ultrasonic range. Upon penetration, the tool leaves a path 15 in the plastic layer 4. A plurality of such paths 15 may thus be worked into the bone cement so that between the paths loose plastic parts are formed which can be removed from the interstice 3. Once the endoprosthesis 2 has been substantially loosened, it can be tapped out of the cylindrical bone. Remaining fragments of the bone cement may remain attached to the inner walls 16 of the bone (FIG. 5). These fragments can be removed quickly and thoroughly, after removal of the endoprosthesis, with the use of tools excited in the ultrasonic range since there now is available sufficient room in the cylindrical bone to use such tools. It is then also possible to introduce ultrasonically excited connecting elements, such as, for example, thread cutters, self-cutting screws or other profiled tools, into the remaining plastic until they have been firmly connected therewith. Then, by applying appropriate forces to these tools, the remainder of the plastic can be removed from the cylindrical bone by breaking, pulling or chiseling. For this purpose, on the shaft 8 appropriate coupling devices are provided to which the appropriate forces can be applied. For example, at the shaft 8, a square coupling 9 can be provided for applying a torque thereto. It is also possible to fasten an abutment plate 28 to the shaft 8 for transmitting a striking energy or pulling forces to the tool.
For further simplification of the work, the sonotrode 6 may be provided with other interchangeable tools. It is conceivable, for example, to design a scoop 17 (FIG. 2) which is placed onto the sonotrode 6. This scoop is provided, at its end remote from the sonotrode 6, with a shallow, spoon-like curvature 18. The curvature 18 is slightly inclined to the side with respect to the direction of the shaft 8 which is to be connected with the sonotrode 6 so that loosened remainders of plastic may collect in the corner zone between the spoon-like curvature 18 and the shaft 8 and can be scraped out of the interstice 3. The inclination is held within the limits which permit optimum energy transfer from the tip of the spoon to the plastic. At its end 19 the spoon-like curvature 18 comes to a relatively sharp point so that the spoon-like curvature 18 can easily penetrate into the plastic layer 4. With the aid of this scoop 17, relatively broad paths can be worked into the plastic layer 4 and the loosened plastic can be removed.
A further tool that may be mounted on the sonotrode 6 is a hollow probe 20 (FIG. 4) which has, at the end of the shaft facing away from the sonotrode 6, a thin tubule 21. This tubule is excited in the ultrasonic range and its open end 22 is pressed into the bone cement. The softened bone cement then travels up the cavity 23 in the tubule 21. After the tubule 21 is filled, the hollow probe 20 is pulled out of the bone cement and the core of plastic is removed from the cavity 23. It is also conceivable to provide a window 24 in the wall of the tubule 21 through which the bone cement traveling up the cavity 23 is continuously extruded,
The removal of the plastic core from the tubule 21 can be simplified by providing the interior of the tubule with a polished surface from which the plastic core slides off with ease. The inner walls of the tubule 21 may be cone-shaped, widening from the open end 22 in the direction toward the shaft 8. The plastic core will then easily slide out of the tubule 21 at its wider open end 22.
Further, a vacuum device may be connected to window 21 to continuously extract the plastic during use of the tool. On the tubule 21a pressure may be applied to facilitate its penetration into the plastic. It is conceivable to press the plastic core out of the tubule 21.
Advisably, the wall of the tubule 21 is honed to form a cutting edge at its end 22 to facilitate penetration of tubule 21 into the plastic. With such a hollow probe it is also possible to work paths into the plastic layer 4 quickly and cleanly. In this way, the plastic layer can be divided into a plurality of individual parts which can be removed from the interstice 3, for example by means of the scoop 17.
Additionally, the cutting edges of all tools may have, e.g. a sawtooth shape. This ensures that upon vibrations in the ultrasonic range, a particularly intensive cutting effect takes place at the protrusions, e.g. at the tips of the sawteeth.
All tools that may be mounted on the sonotrode 6 have the advantage that they are small and convenient, making possible a penetration even into narrow interstices 3. The tools have a thickness of only a few millimeters, but may be up to 300 mm long, without causing a significant energy loss along the tool to its tip.
It is thus possible with the aid of these tools to remove bone cement even from the usually inaccessible places between implant and bone. With a small cold light source 25 (FIG. 5) which can be fastened, for example, on the shaft 8 or on the sonotrode 6, a focused beam of light 26 is guided in the direction toward the point where the tool is being used. It illuminates the field of the operation so that the surgeon can always guide the tool into the correct direction. In this way it is possible to remove the bone cement, even at inaccessible places, easily, quickly, without shock and thus without damage to tissue and particularly to bone tissue. In addition, in the immediate vicinity of the operating field, a suction device 27 may be provided with the aid of which the gases as well as blood and wound secretions developing during working of the plastic can be extracted. Thus the field of the operation will always be kept free of impurities and the surgeon will retain a good field of view.
In the compound system, nonmetallic prosthesis parts, which may be duraplastics, can also be worked on directly with the above described tools. Thus these prosthesis parts can be removed quickly so that the operating field is enlarged accordingly and the interior of the cylindrical bone can be cleaned quickly and neatly of any remaining fragments.
It is possible, within the scope of compound osteosyntheses, to connect metallic materials with the soft bone cement while it is still in the hardening phase or to encase them in such bone cement. Improperly inserted nails and plates can be disengaged with the aid of ultrasonic tools, for re-insertion at a different location. It is feasible to couple the metallic osteosynthesis parts directly to the sonotrode 6 and removed from the bone cement.
When replacing vertebrae with artificial members, the artificial vertebrae formed of bone cement are shaped during the operation to conform to the anatomy and are placed into their position. Then the artificial vertebrae are fused to each other and to the healthy vertebrae to conform to the individual anatomy. If further artificial vertebrae need be implanted at a later date, the older compound system can be loosened with the aid of ultrasonically excited tools and can be replaced by a new one.
Moreover, the method of the invention can be used for working on prostheses in the area of the cranium. For example, bone cement can be shaped to replace the top of the cranium so as to repair possible damage to the top of the cranium. After filling up the damaged portions, it is generally necessary to subsequently mechanically shape the prosthesis to adapt it to the remaining bone substance. The mechanical adaptation and shaping results in jarring of the skull which endangers the firm seat of the implant. With the aid of ultrasonic tools, such work can be performed essentially without jarring; thus, these tools can be used to perform subsequent work without endangering the success of the operation.
It is to 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 ultrasonic tool is used for dissolving the bond between nested components cemented together by a plastic layer. The vibrating tool causes softening of at least portions of the plastic layer, and subsequently the components can be readily detached from one another. | 1 |
This is a division of application Ser. No. 145,025 filed Apr. 30, 1980 abandoned.
TECHNICAL FIELD
This invention relates to a light-sensitive composition which is water or aqueous solvent developable. More specifically, the invention relates to a light-sensitive adduct which is derived from combining a resin having a plurality of pendant diazonium sites, i.e., a diazo resin, with a polymer having a plurality of sulfonated groups.
BACKGROUND ART
Diazonium compounds are well known and widely used in the preparation of negative-acting lithographic printing plates to impart light sensitivity thereto. Upon exposure, the photochemical decomposition of the diazonium salt produces physical and chemical changes, such as crosslinking, insolubility, increased adhesion, etc. Most commonly utilized diazonium compounds are the diazo resins, such as those described in U.S. Pat. No. 2,714,066, which are synthesized by the condensation reaction of an active carbonyl compound with a diazo compound.
These diazonium resins are disclosed in many patents and have been coated either alone, such as in U.S. Pat. No. 2,714,066; overcoated with a resinous layer, such as is disclosed in U.S. Pat. No. 3,136,637; overcoated with a photopolymer, such as is disclosed in U.S. Pat. No. 3,905,815; or included in conjunction with other resinous materials such as is disclosed in U.S. Pat. No. 3,660,097.
Variations in the properties of diazo resins have been achieved by employing different anions therewith, e.g., as is disclosed in U.S. Pat. No. 3,790,556, wherein the solubility properties thereof are changed as well as humidity resistance, i.e., storage life. Furthermore, simple monomolecular diazonium salts have been reacted with high molecular weight sulfonated phenol-formaldehyde resins, as disclosed in U.S. Pat. No. 3,199,981, to prepare, in association with other resins, positive printing plates from positive originals.
One common characteristic of light-sensitive lithographic plates utilizing diazo resins is that the resin has a tendency to remain or adhere in the non-image areas after chemical development or processing. This small amount of unremoved resin results in an ink toning and scumming condition in the background of the plate during the subsequent printing process. The reasons for the unremoved diazo resin in the non-image areas are believed to be due to physical attachment thereof to the substrate, insoluble fractions, minor decomposition products, or perhaps for a combination of these reasons. This specific problem is typically solved by utilizing special chemicals in the developer, typically called desensitizing agents, which aid in the removal of this unexposed diazo resin material. For example, U.S. Pat. Nos. 3,905,815; 3,891,438; 3,891,439; and 3,669,660 disclose solutions to the foregoing problem.
Surprisingly, I have now found a light-sensitive adduct derived from a combination of a diazo resin having a plurality of pendant diazonium sites with a polymer having a plurality of sulfonated groups, the adduct being capable of eliminating the problem discussed above. While it might be anticipated that such a combination of polyionic species would result in a completely insoluble ionically crosslinked mass, not suitable for printing plate utility, such has not been the case. A soluble and highly useful material for presensitized printing plates has resulted from the combination. In fact, the use of this adduct in a presensitized printing plate construction allows for the substantial elimination of the necessity for desensitizing salts in a developer solution.
A wide variety of simple developers and techniques can be utilized to prepare a printing plate made with the adduct, such as water or water/alcohol, simple machine processors, and, in some instances, on-press processing. Obviously, the simplicity of the developer used in providing the printing plate is environmentally desirable because of the reduced necessity for desensitizing agents and conventional harsh or polluting developers.
DISCLOSURE OF INVENTION
In accordance with the invention, there is provided a light-sensitive adduct comprising the combination of a diazo resin having a plurality of pendant diazonium groups with a sulfonated polymer having a plurality of sulfonate groups, and a presensitized light-sensitive article capable of providing a lithographic printing plate.
The use of the adduct in a coating composition to provide a presensitized lithographic plate affords the ability to develop and desensitize an exposed plate with water or simple aqueous developers.
DETAILED DESCRIPTION
As used herein, the term "adduct" is defined as the product derived from the addition of a diazo resin having a plurality of pendant diazonium groups with a sulfonated polymer having a plurality of sulfonate groups.
Exemplary diazo resins suitable for use in my invention are described in U.S. Pat. No. 2,714,066, with the preferred resins being the salts of the condensation product of paraformaldehyde and p-diazodiphenylamine. The anion associated with the diazo resin is not of particular importance with the exception of solubility characteristics relative to the reaction and coating solvent used.
Exemplary sulfonated polymers having utility herein include the alkali metal salt polyesters described in U.S. Pat. No. 4,052,368. These materials ar particularly useful due to the wide variety and concentrations of diols, sulfomonomer and carboxylic acids that may be selected. Other sulfonated polyesters having utility herein include those disclosed in U.S. Pat. Nos. 3,779,993; 3,639,352; and 3,853,820.
These sulfonated polyesters are prepared by conventional techniques, typically involving the reaction of dicarboxylic acids (or diesters, anhydrides, etc. thereof) with monoalkylene glycols and/or polycaprolactone diols in the presence of acid catalysts, such as antimony trioxide, utilizing heat and pressure as desired. Normally, an excess of the glycol is supplied and subsequently removed by conventional techniques during the later stages of polymerization. When desirable, a hindered phenol antioxidant may be added to the reaction mixture to protect the polyester from oxidation.
Another class of useful sulfonated polymers includes the sulfonated polyurethanes having hydrophilic and hydrophobic segments as described in U.S. Pat. No. 4,307,219. These materials are derived from low molecular weight sulfonated polyester prepolymers, diisocyanates, and, optionally, various chain extenders. These polymers also provide a reactive sulfonate moiety which combines readily with a diazo group, and exhibit good physical properties such as flexibility, non-tackiness, abrasion resistance and water or water/alcohol dispersability.
Hydrophilic diols useful in the preparation of these polyurethanes are the bis(ω-hydroxyaliphatic) esters of sulfosubstituted aromatic dicarboxylic acids.
Examples of diols used for the hydrophobic segment of the sulfonated polyurethane polymers are aliphatic and cycloaliphatic diols, optionally containing aromatic groups and low molecular weight polyoxyalkylene diols. Exemplary compounds include butane diol, neopentyl glycol, polycaprolactone diol, and bis-(hydroxyethyl)terephthalate. Other examples include the well-known polyester diols generally prepared by the condensation of one or more diols with one or more dicarboxylic acids, such as succinic acid, adipic acid, and maleic acid.
Diisocyanates useful in preparing these polyurethanes include tolylene-2,4-diisocyanate and diphenylmethane-4,4-diisocyanate, among others.
These sulfonated polyurethanes are prepared in solution under anhydrous conditions using conventional polyurethane preparation methods.
These linear polyurethanes provide a reactive sulfonate moiety which can combine with the diazo resin moiety as well as provide physical properties desirable for lithographic plates, such as flexibility, abrasion resistance, water or alcohol/water solubility/dispersibility, hydrophobicity, etc.
Since diazo resins are cationically charged and sulfonated polymers anionically charged, the reaction between the two is believed to be of an ion exchange type, and in some instances the light-sensitive adduct formed can be precipitated and isolated as a powder or as a somewhat gummy material.
Separate solutions of the sulfonated polymer and diazo resin can be prepared such that the ratio of diazonium ions to sulfonate ions is 1:1. The solutions can then be combined and the resulting precipitate washed with water and dried. The yield is virtually quantitative when the stoichiometry is 1:1. For other ratios, the product may not precipitate in a filterable state and remain suspended. When the adduct is derived from a sulfonated polyester with a diazo, the salt precipitates as a gummy material, whereas the sulfonated polyurethane/diazo reaction product is generally a fine, easily filterable, amorphous solid.
Solvent systems are chosen such that the sulfonated polymer and diazo resin are both soluble therein, while the adduct is not. Aqueous alcohol solutions are most advantageous for use in the preparation of the adduct if isolation thereof is desired.
The diazo/sulfonated polymer adduct can be redissolved in polar solvents such as dimethylformamide, γ-butyrolactone, and N-methylpyrrolidinone. Once dissolved, it has been found that a solution can be further diluted with other solvents as 2-methoxyethanol, methyl ethyl ketone, 1-propanol, ethylene dichloride, etc. The adducts are also soluble in non-solvents, such as 2-methoxyethanol, which contain some of the sulfonated resin dissolved therein.
To prepare a coating solution for preparation of a printing plate, an adduct can be prepared as above and simply dissolved in a suitable solvent. Alternatively, solutions of the sulfonated polymer and diazo resin can be prepared using a solvent system in which the resulting adduct is also soluble. In this manner, a coating solution can be directly prepared. Suitable solvents are essentially the same as noted above and include 2-methoxyethanol, dimethyl formamide, γ-butyrolactone, N-methyl pyrrolidinone, and combinations thereof.
Coating solution concentration can typically range from about 1 to about 20 percent by weight, depending on the coating method chosen, solution viscosity, the desired dry coating weight, and the avoidance of precipitation.
For the preparation of a light sensitive printing plate, it has been found that the ratio of diazo to sulfonate equivalents should be less than about 1.5 to 1, with from 0.1 to about 0.6 to 1 being preferred. As increasing equivalents of diazo are used, the ability of the resultant plate to be desensitized is reduced, because less diazo is tied to the sulfonate groups, and additional agents become necessary in the developer.
The sulfonated polymer should contain one sulfonate group per about 500 to about 8,000 molecular weight of polymer, with the preferred range being from about 1500 to about 3,000 molecular weight. As the sulfonate equivalent weight increases, the diazo can become diluted in the sulfonate polymer, thereby reducing light sensitivity. Therefore, the ratio of diazo equivalents should be correspondingly increased to impart increased light sensitivity and physical characteristics.
For presensitized printing plate formulations, polymeric thermoplastic resins may be used as additives, in conjunction with the compositions of my invention to modify or improve the physical properties of the coating. For example, properties such as developer solubility, abrasion resistance, ink receptivity, press life, etc. can be influenced by the addition thereof in amounts from about 20 to about 60 percent by weight. Suitable resins include the sulfonated polymers themselves, polyesters, polyurethanes, nylons, vinylidene chloride copolymers, polyvinyl esters, polyacrylates, and alpha-alkyl polyacrylates, polyvinyl chloride, polyvinyl acetals, and polyvinyl alcohols, among others. The amount and type of resin added to improve the plate formulation depends upon the specific property being altered and is arrived at (by trial and error) emperically.
Substractive presensitized plates are also typically formulated with pigments or dyes to facilitate manufacturing control and visual appearance of the product, as well as to aid in using the plate relative to positioning, developing, etc. Pre-dispersed pigments such as Microlith Blue (tradename for phthallocyanine pigment pre-dispersed in a vinyl resin, available from Ciba Geigy) are useful at from about 5 to about 20 weight percent of the coating. Pigments such as Monastral Blue can also be used in the same general concentration range using standard milling dispersion techniques. Dyes such as triphenyl methane dyes, e.g., Victoria Blue B0, commercially available from duPont, are also useful as coloring agents, preferably at from about 2 to about 5 percent by weight of the coating.
Dyes which provide a visible image upon exposure to actinic radiation may also be incorporated in the formulation to aid a user in visualizing the exposed plate prior to development. Conventional well-known leuco dye and acid-base dye printout systems can be utilized. An exemplary material is 4-(phenylazo)-diphenylamine, which can be used at from about 1 to 2 percent by weight of the coating.
In addition, photopolymerizable components may be incorporated into the formulation to enhance the solubility differential between image and non-image areas. Unsaturated polyfunctional monomeric or oligomeric compounds, which can be polymerized under the influence of light, include acrylic esters, acrylamides, etc. Preferably, a photoinitiator would also be included in the photopolymer formulation at from about 1 to about 5 percent by weight of the coating. Preferred photoinitiators include the chromophore-substituted vinyl-halomethyl-s-triazines disclosed in U.S. Pat. No. 3,987,037.
The photosensitive solutions can be coated on sheet materials such as paper, plastic, or metal and preferably on those that are permanently hydrophilic and conventionally used in the preparation of lithographic plates. Aluminum, which has first been cleaned and treated to render same permanently hydrophilic is the preferred substrate. Well-known methods of treatment include silicating, electrolytic anodizing, mechanical graining, or combinations thereof. In addition to providing a durable hydrophilic background, the type of treatment can also influence coating performance characteristics, such as exposure time, ease of development, image adhesion, press life, etc. The versatility and wide variety of light sensitive coating compositions made possible by my invention allows one to select or arrive at preferred combinations of base and coating to achieve optimum performance.
Coating weights in the range of from about 5 to about 150 milligrams per square foot may be used, with from about 20 to about 80 milligrams per square foot being preferred.
If desired, the coating solution can be overcoated onto a diazo presensitized base such as described in U.S. Pat. No. 2,714,066. In this case, excess sulfonated polymer is used, wherein the sulfonated polymer combines with the diazo layer which affords desensitization of the background without necessity of added desensitizing salts in the developer. Improved humidity resistance has also been noticed.
Developers useful for developing the imaged composition include aqueous solutions with or without the inclusion of organic solvents, buffers, desensitizers, surfactants, stabilizers and gums. In general, the adducts of sulfonated polyesters can be developed with water or in fact press-developed, whereas many of the adducts of polyurethanes, while they can be developed with water alone, are more easily developed with dilute alcohol-water solutions. Exemplary alcohols include ethanol, 1-propanol, 2-propanol, benzyl alcohol and 2-methoxyethanol, and can be used at a concentration of from about 5 to about 37 percent by weight, depending on the alcohol selected and its solvent power. For example, the concentration of 1-propanol or 2-propanol at 20 to 37 percent by weight is preferred, whereas that preferred for 2-methoxyethanol and benzyl alcohol is from about 5 to about 10 percent by weight. Other water-miscible solvents which can be used include ethylene glycol diacetate and γ-butyrolactone.
The addition of anionic surfactants or desensitizing salts to an alcohol/water solution results in a developer which dissolves the coating in the non-image areas of the plate, rather than merely facilitating the physical scrubbing off of the coating. This provides the easiest development and is required for simple dip-tank mechanical plate processors.
Exemplary anionic surfactants include arylsulfonates such as sodium dodecylbenzenesulfonate and dimethyl-5-sodiumsulfoisophthalate, sulfate salts of aliphatic alcohols such as sodium lauryl sulfate, and sodium dialkyl sulfosuccinates such as dioctyl sodium sulfosuccinate.
Exemplary desensitizing salts include ammonium sulfite, sodium sulfite, etc. The surfactants or desensitizing salt can be used in a concentration of from about 0.5 to 10 percent by weight, and preferably from about 0.5 to 2.0 percent by weight of the developer solution.
The invention will now be more specifically described by use of the following non-limiting examples, wherein all parts are by weight unless otherwise specified.
EXAMPLE 1
Preparation of a Sulfonated Polyester
A 1,000 ml three-necked, round-bottomed flask equipped with a sealed stirrer, thermometer, and condenser was charged with 74.1 grams (25 mole percent) of dimethyl-5-sodium sulfoisophthalate, 145.6 grams (75 mole percent) of dimethyl terephthalate, 26.5 grams (50 mole percent) of polycaprolactone diol (PCP-0200, commercially available from Union Carbide), 62 grams (100 mole percent) of ethylene glycol, 0.06 gram of zinc acetate and 1.5 grams of sodium acetate. The flask and contents were flushed with nitrogen to remove air and thereafter during the esterification an inert atmosphere was maintained by passing a slow flow of nitrogen through the apparatus.
The reaction mixture was stirred and heated between 180° C. and 200° C. for 97 minutes, or until the pot temperature rose to 200° C., indicating that most of the methanol from the transesterification reaction had been removed. Over a 30 minute period, the temperature was raised to 225°-235° and maintained while pressure was slowly reduced to 0.18-0.25 Torr over a period of 25 minutes and excess ethylene glycol was removed. The system was then brought to atmospheric pressure with nitrogen and the hot polymer drained into a polytetrafluoroethylene-coated pan, yielding a water soluble resin. The sulfonate equivalent weight of the resin was calculated to be 1800. Other sulfonated polyesters prepared by this method which are examples of polymers useful in the invention are listed in Table I.
TABLE I__________________________________________________________________________ Mole Mole Mole Mole Mole Mole Sulfonate Percent Percent Percent Percent Percent Percent EquivalentEx. DMSSIP.sup.(1) DMT.sup.(2) Other PCP.sup.(3) EG.sup.(4) Other Weight__________________________________________________________________________2 10 90 15 85 27263 15 85 50 50 29424 25 75 25 75 13395 25 75 95 5 26496 15 65 20 100 1431 Sebacic Acid7 25 75 100 27438 25 75 70 30 2181 (hexane diol)__________________________________________________________________________ .sup.(1) DMSSIP = Dimethyl5-sodium sulfoisophthalate .sup.(2) DMT = Dimethyl terephthalate .sup.(3) PCP = Polycaprolactone diol .sup.(4) EG = Ethylene glycol
EXAMPLE 9
Preparation of a Sulfonated Prepolymer
A 1,000 ml three-necked, round-bottomed flask equipped with a sealed stirrer, nitrogen purge and a condenser set for distillation was charged with 88.9 grams (0.30 moles) dimethyl-5-sodiumsulfoisophthalate, 318 grams (0.60 moles) of PCP-0200 (tradename for a polycaprolactone diol, molecular weight 530, available from Union Carbide), 0.04 gram of tetraisopropyl titanate and 0.8 gram of triethylamine. The flask and contents were flushed with nitrogen to remove air and thereafter during the transesterification an inert atmosphere was maintained by passing a slow flow of nitrogen through the apparatus.
The reaction mixture was heated in a 230° C. Woods metal bath for 1.5 hours or until the distillation of methanol ceased. The pressure was slowly reduced to 20 Torr and that pressure was maintained for 15 minutes. The system was then brought to atmospheric pressure with nitrogen and the hot prepolymer drained into glass jars and sealed. The hydroxyl equivalent weight was determined by the phenyl isocyanate titration method using diglyme as the solvent. The hydroxyl equivalent weight of this example was 1,000 and can range from 750 to 1500.
EXAMPLE 10
Preparation of a Sulfonated Polyurethane Resin
In a 1,000 ml three-necked, round-bottomed flask equipped with a stainless steel stirrer, inert gas inlet and a reflux condenser, were charged 200 grams (0.10 moles) of the sulfonated prepolymer from Example 9. The prepolymer was dissolved in 200 grams of dry methyl isobutyl ketone with stirring at 100° C. The solution was cooled to 60° C. and 87.0 grams (0.50 moles) of tolylene-2,4-diisocyanate was charged in one portion. The reaction mixture was stirred at 80° C. for 30 minutes, after which 85.2 grams (0.2 moles) of diol (2:1 cyclohexane dimethanol:maleic anhydride condensation product) were charged.
The reaction was stirred for an additional 30 minutes at 80° C., after which 12.4 grams (0.20 moles) of ethylene glycol was charged. The reaction temperature was raised to 115° C. and stirring was continued for 2 to 3 hours (or until the high viscosity of the reaction prevents stirring). The reaction was quenched by the slow addition of 300 grams of 2-methoxyethanol, and the finished polymer was stored in solution. The sulfonate equivalent weight of the polymer was 2,485.
Examples of other polyurethane compositions are illustrated in Table II.
TABLE II__________________________________________________________________________ SulfonateEx- Sulfonated Molecular Unsat'd Butane Pentane Hexane Equivalentample Prepolymer Weight TDI.sup.(1) MDI.sup.(2) PCP-0200.sup.(3) BHET.sup.(4) Diol.sup.(5) EG.sup.(6) Diol Diol Diol Weight__________________________________________________________________________11 1 1950 2 1 179112 1 1950 2 1 170113 1 1950 2 1 197414 1 1700 3 2 266815 1 1700 4 3 326016 1 1700 3 2 233417 1 1700 5 2 2 269518 1 2190 5 2 2 276119 1 2190 7 2 4 316220 1 2190 7 2 4 319521 1 2190 3.5 0.5 2 208722 1 2190 5 2 2 260523 1 2190 2 1 174824 1 2190 3.5 2 .5 2452__________________________________________________________________________ .sup.(1) Tolylene 2,4diisocyanate .sup.(2) Methylenebis(4phenyl isocyanate) .sup.(3) Polycaprolactone diol, 530 MW (Niax Polyol, Union Carbide) .sup.(4) Bis(hydroxyethyl) terephthalate .sup.(5) 2:1 condensation product cyclohexanedimethanolmaleic anhydride (426 MW) .sup.(6) Ethylene glycol
EXAMPLE 25
Preparation of a Polyester-Diazo Adduct
A photosensitive polymeric diazonium-sulfonated polyester adduct was prepared as follows:
Three grams of the sulfonated polyester of Example 3 was calculated to contain 1.0 milliequivalent of sulfonate ion. This was dissolved with stirring in 15 percent 1-propanol/water at 5 percent solids to furnish a clear solution. This solution was further diluted to 1 percent solids and cooled to 10° C. To this chilled solution were added dropwise with stirring 32 ml of a 1 percent solution (1.0 milliequivalent) of the zinc chloride double salt of the formaldehyde condensation product of p-diazodiphenylamine. At the end point a cheesy solid agglomerated which was filtered and washed with cold water. The solid could be dried in vacuo, if desired, or immediately dissolved and coated.
Adducts of the other polyesters listed in Table I can be prepared in a similar manner.
EXAMPLE 26
Preparation of a Polyurethane-Diazo Adduct
Twenty-seven grams of the sulfonated polyurethane of Example 17 was dissolved in 270 ml of 20 percent 1-propanol/water. The resulting clear solution was calculated to contain 1.0 milliequivalent of sulfonate ion. This solution was cooled to 10° C. and added over 15 minutes to a cold, stirred solution of 3.12 grams (1.0 milliequivalent) of the zinc chloride double salt of the formaldehyde condensation product of p-diazodiphenylamine. At the end point a fine granular precipitate formed which was filtered, washed with water and dried in vacuo. If allowed to dry in air, the product darkens noticeably.
Adducts of the other polyurethanes listed in Table II can be prepared in a similar manner.
EXAMPLE 27
A coating solution was prepared by mixing the following ingredients:
______________________________________ Parts by Weight______________________________________Sulfonated polyester ofExample 5 1.00Diazo sensitizer* .05Victoria Blue Dye (duPont) .022-Methoxyethanol 19.0______________________________________ *triisopropylnaphthalene sulfonate salt of the formaldehyde condensation product of 4diazodiphenylamine
whereby the ratio of diazo to sulfonate equivalents was 0.24 to 1.
The solution was coated onto a silicated aluminum foil paper laminate at 30 milligrams per square foot dry coating weight and dried. The plate was exposed imagewise and mounted on an AM 1250 printing press. By dropping the dampening rollers for 10 revolutions, followed by 10 revolutions with the ink rollers, the fifth copy printed had a dense image area and a clean, scum-free background. Alternatively, the plates could be developed with tap water. The plate rolled up clean even after oven storage at 140° F. for 3 days.
The preferred sulfonated polymers for this plate are the sulfonated polyesters, and in particular those which contain from 70 to 100 mole percent polycaprolactone diol and 25 mole percent sodium sulfoisophthalate (Examples 5, 7 and 8).
EXAMPLE 28
The diazo polyester adduct of Example 25 can be dissolved in a solution of additional polyester and coated on silicated aluminum to prepare a water-developable short run plate. A coating solution was prepared and coated as in Example 27 containing:
______________________________________ Parts by Weight______________________________________Sulfonated polyester ofExample 3 .50Diazo-polyester adduct ofExample 25 .50Victoria Blue Dye (duPont) .022-Methoxyethanol 19.0______________________________________
resulting in a ratio of diazo to sulfonate equivalents of 0.48 to 1.
The solution was coated onto silicated smooth aluminum at 30 milligrams per square foot dry coating weight and dried in a stream of warm air. After exposing imagewise to actinic radiation, the plate was developed with tap water and gentle scrubbing, furnishing a plate with a clean background (totally desensitized) and an oleophilic image area. The plate was still easily water developed after three days at 140° F. storage. Water developable plates can also be prepared using the solution method of Example 27, rather than by separate preparation of the diazo adduct.
Several of the sulfonated polyurethanes are also suited for water-only developable plate coatings using the methods in Examples 27 and 28 including Examples 11-15, 21, 23, and 24.
EXAMPLE 29
Sulfonated polyurethanes can be combined with sulfonated prepolymers to enhance water developability. A coating solution was prepared by mixing the following ingredients until homogeneous:
______________________________________ Parts by Weight______________________________________Sulfonated polyurethane ofExample 17 .90Diazo sensitizer* (added as10% solution in dimethylformamide) .05Sulfonated polyester prepolymerof Example 9 .10Microlith Blue 4G-T pigment(added as 18% solution inmethyl ethyl ketone) .144-Phenylazodiphenylamine .022-Methoxyethanol 19.0______________________________________ *BF.sub.4 salt of the formaldehyde condensation product of 4diazodiphenylamine
resulting in a ratio of diazo to sulfonate equivalents of 0.41 to 1.
The solution was coated on smooth silicated aluminum to a dry coating weight of 50 milligrams per square foot, dried in a stream of warm air and exposed imagewise to actinic radiation. The plate was easily developed with tap water and gentle scrubbing. Other polyurethanes which can be utilized include Examples 16 and 21.
EXAMPLE 30
Another method to prepare water developable printing plates with the polyurethanes of Examples 17, 18, and 22 is to use a diazo salt other than a tetrafluoroborate salt.
A coating composition was prepared by milling the following ingredients until homogeneous:
______________________________________ Parts by Weight______________________________________Sulfonated polyurethane ofExample 17 1.00Diazo sensitizer** .10Monastral Blue G pigment (duPont) .104-Phenylazodiphenylamine .022-Methoxyethanol 10.0______________________________________ **2-hydroxy-4-ethoxybenzophenone-5-sulfonate salt of the formaldehyde condensation product of 4diazodiphenylamine
resulting in a ratio of diazo to sulfonate equivalents of 0.52 to 1.
The solution was coated as in Example 30. The plate thus prepared was developed and desensitized using tap water and gentle scrubbing.
For coating compositions containing sulfonated polymers with lesser amounts of sulfonate and/or polycaprolactone, than used for Examples 27-29, the ease of water development decreases. Aqueous solutions containing small amounts of organic solvents are, however, useful as developers for these compositions. Alcohols such as ethanol, 1-propanol and benzyl alcohol; ether-alcohols such as 2-methoxyethanol; ketones such as acetone, methyl ethyl ketone and cyclohexanone and esters such as ethyl acetate may be used at from 1 to 40 percent by weight in water to develop and desensitize plates. The optimum solvent concentration is best determined empirically for a given plate construction to achieve the optimum solubility differential between image and background. The polyesters of Examples 2 and 4 and the polyurethanes of Examples 16-20 are representative of sulfonated polymers which, when coated with diazo, are water developable with some difficulty, but are easily developed with these developers.
EXAMPLE 31
A coating solution was prepared by mixing the following ingredients:
______________________________________ Parts by Weight______________________________________Sulfonated polyurethane ofExample 17 .90Diazo sensitizer (BF.sub.4 salt asin Example 29) .05Monastral Blue G pigment (duPont) .104-(Phenylazo) diphenylamine .022-Methoxyethanol 19.0______________________________________
resulting in a ratio of diazo to sulfonate equivalents of 0.51 to 1.
The solution was milled to suspend the pigment and then coated as before to a dry coating weight of 50 milligrams per square foot. The plate was easily developed and desensitized with hot water (120° to 130° F.), but not with water at room temperature. The plate can be easily developed with 20 percent by weight 1-propanol/water at normal temperatures (55° to 90° F.).
EXAMPLE 32
The addition of photopolymerizable components (e.g., polyfunctional acrylate ester monomers) to the sulfonated polymer/diazo coatings generally results in increased solvent resistance after exposure. On grained surfaces the monomeric components also improve the developability of the coatings.
A coating composition was prepared by milling the following ingredients until homogeneous:
______________________________________ Parts by Weight______________________________________Sulfonated polyurethane ofExample 20 .70Diazo sensitizer (BF.sub.4 salt asin Example 29) .05Monastral Blue G pigment (duPont) .10Triacrylate of tris-hydroxyethylisocyanurate (Sartomer resinSR-368) .302-(p-methoxystyryl)-4,6-bis-(trichloromethyl)-s-triazine .032-(p-dimethylaminostyryl)quinoline .022-Methoxyethanol 19.0______________________________________
resulting in a ratio of diazo to sulfonate equivalents of 0.77 to 1.
The mixture was coated on smooth silicated aluminum as before and developed with an aqueous developer of the type described in Example 31.
EXAMPLE 33
Under certain circumstances it is desirable to improve the ease of development to the point where the developer actually dissolves the plate coating in the non-image areas. This allows rapid development of a plate without any scrubbing action and also makes possible the use of simple automatic plate processors. The use of certain developers with the coatings of this invention eliminates the need for complicated plate processors which may require pumps, filters, heaters and elaborate scrubbing mechanisms.
A coating composition was prepared by milling together the following ingredients until homogeneous:
______________________________________ Parts by Weight______________________________________Sulfonated polyurethane ofExample 17 .43Diazo-polyurethane adduct ofExample 27 .45Monastral Blue G pigment (duPont) .0874-Phenylazodiphenylamine .01Polyacrylic acid (Acrysol A-3,Rohm & Haas) .0252-Methoxyethanol 19.0______________________________________
resulting in a ratio of diazo to sulfonate equivalents of 0.49 to 1.
The solution was coated as before on smooth, silicated aluminum, dried and imaged. Samples were developed with the solutions listed in Table III.
TABLE III______________________________________DEVELOPER COMPOSITIONSParts by WeightExample No.: 34 35 36 37______________________________________water 59.75 73 94 931-propanol 37.0 25benzyl alcohol 5 3ethylene glycol diacetate 3trisodium EDTA 0.25monoammonium phosphate 1.5ammonium sulfite 1.5sodium dodecylbenzene-sulfonate 1 1dimethyl sodium-5-sulfoiso-phthalate 2.0______________________________________
All of the above developers dissolved the plate coating in the non-image areas when the plate was soaked in a static bath for 10 to 20 seconds. This allows the use of simple processors if desired. Alternatively, a developing pad may be used, in which case development is virtually instantaneous. In addition, these developers may be used with the plates described in Examples 30-33.
EXAMPLE 38
The polyurethane-diazo adduct can also be coated alone on silicated aluminum to produce a printing plate. A mixture of the following components was prepared by milling the following ingredients until homogeneous:
______________________________________ Parts by Weight______________________________________Polyurethane-diazo adductof Example 26 1.00Monastral Blue G pigment .104-Phenylazodiphenylamine .02Dimethyl formamide 19.0______________________________________
The mixture was coated on smooth silicated aluminum to a dry coating weight of 50 milligrams per square foot and imaged in the conventional manner. The plate could be developed using any of the developers of Table III.
EXAMPLE 39
The coating solution of Example 33 was coated over a silicated aluminum sheet which had been previously sensitized with the zinc chloride double salt of the formaldehyde condensation product of 4-diazodiphenylamine. The plate thus produced had superior storage properties in high humidity, high temperature environments and still behaved as the plates of Example 33 relative to development characteristics. | A light-sensitive adduct comprising the combination of a diazo resin having a plurality of pendant diazonium groups and a sulfonated polymer having a plurality of sulfonate groups and a presensitized light-sensitive article comprising a substrate having a light-sensitive coating which is comprised of the light-sensitive adduct on a surface thereof. After imagewise exposure, unexposed portions of the coating are removable by water or aqueous developers. | 2 |
This application is a continuation-in-part of U.S. Ser. No. 11/228,719, filed on Sep. 16, 2005, which claims the benefit of prior provisional U.S. Ser. No. 60/610,658, filed on Sep. 17, 2004.
FIELD OF THE INVENTION
The present invention is directed to two sets of specialty tailored package components for use in the radiochemical (RCS) process of medical devices in hermetically sealed foil packs using a combination of low-dose, high-energy radiation and paraformaldehyde, as a highly effective source of radiolytically generated formaldehyde gas, in combination with an inert or adsorbing solid dispersant wherein either of said combinations are contained in a porous barrier adjacent to a perforated device holder, or a liquid formulation in a sealed, flexible dispenser.
BACKGROUND OF THE INVENTION
Prior application U.S. patent application Ser. No. 11/228,719, filed on Sep. 16, 2005, by one of the present inventors has dealt with package components for radiochemical sterilization of medical or pharmaceutical products consisting of a hermetically sealed foil pack containing (1) a solid device, as in absorbable sutures and meshes, in a perforated holder or a liquid formulation in a sealed, flexible dispenser, as in absorbable cyanoacrylate-based tissue adhesive; (2) a microparticulate, unstabilized polyformaldehyde as a source of radiolytically generated formaldehyde encased in a sealed pouch comprising a porous, non-woven or woven fabric; and (3) a nitrogenous compound capable of reacting with residual formaldehyde, such as melamine or urea, that is encased in a sealed pouch comprising a porous, non-woven or woven fabric. However, only a small fraction representing less than 3 weight percent of the microparticles of unstabilized polyformaldehyde used to produce formaldehyde gas radiolytically was responsible for releasing the sterilizing dose of the formaldehyde gas. This leaves more than 95 percent of unused polymer mass. Such behavior may be attributed to the establishment of equilibrium between the monomeric and polymeric formaldehyde, which compromises the efficiency of the formaldehyde precursor. This provided an incentive to pursue the study associated with the instant invention, which entails the use of (1) a cyclic, thermodynamically less stable formaldehyde precursor compared to the linear polymeric polyformaldehyde described in the parent application; (2) an organic polymeric microparticular dispersant that lowers the mass of the active gas precursor per unit volume in the package insert, which facilitates the gas diffusion and minimizes the overall mass of the precursor; and (3) an organic granular desiccant dispersant, which not only lowers the mass of the precursor, but also acts as a desiccant to maximize the shelf-life stability of the sterilized absorbable device.
SUMMARY OF THE INVENTION
In a general aspect of the present invention is directed to a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein the outer sheet comprises a laminated foil and the porous pouch comprises a non-woven fabric construct of a polyolefinic material selected from polyethylene, polypropylene, and ethylene-propylene copolymer.
A specific aspect of this invention deals with a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein dispersant powder is an organic polymer selected from polyethylene, polypropylene, polyethylene terephthalate, and polytetramethylene terephthalate. Alternatively, the dispersant powder is an inorganic desiccant, such as silica gel.
A special aspect of the invention deals with a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein the holder is a perforated folder made at least one material selected from cellulose, polyethylene, polypropylene, ethylene-propylene copolymer, and polyethylene terephthalate, and wherein the medical device can be (a) an absorbable suture, (b) an absorbable composite surgical mesh, (c) a partially absorbable composite surgical mesh, (d) a partially absorbable composite vascular repair device, (e) a composite urinary bladder repair device, (f) a composite polymeric stent for repairing at least one body conduit selected from ureters, urethra, blood vessels, and esophagi, or (g) an absorbable composite device for internal bone fixation.
A second special aspect of this invention deals with a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein the medical device is a cyanoacrylate tissue adhesive and the holder therefor is a gas-tight container, wherein the gas-tight container is a sealed, squeezable ampoule formed from a polymer selected from polyethylene, polypropylene, ethylene-propylene copolymer, and polyethylene terephthalate. Alternatively, the gas-tight container is a screw-capped glass vial.
A third special aspect of the invention deals with a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein the medical device is a self-setting, composite absorbable bone cement or bone filler and the holder therefor is a squeezable, gas-tight container, and wherein the bone cement or bone filler preferably is a cyanoacrylate monomer.
A technologically important aspect of this invention deals with a hermetically sealed package for use in radiochemical sterilization of at least one medical device contained therein which includes an essentially gas impervious, moisture impervious sealed outer sheet, a holder for the medical device, and a sealed, porous pouch contained within the sealed outer sheet and containing a mixture of radiolabile paraformaldehyde particles and radiostable dispersant powder at a weight ratio of less than 1:2, wherein the hermetically sealed package is radiochemically sterilized by irradiating the package with gamma rays or E-beam at a dose of less than 11 kGy.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
This invention presents substantial improvements over the prior art on radiochemical sterilization, which, in turn, makes this technology more practical to use and adds new packaging attributes pertaining to the ease of package assembling and shelf-stability of radiochemically sterilized, absorbable medical devices. From a technological perspective this invention teaches the use of smaller amounts of paraformaldehyde, comprising a low melting mixture (T m <150° C.) and low molecular weight oxymethylene-based chains, as a more effective source of formaldehyde compared to the linear, high molecular weight, high melting (T m >160° C.) polyformaldehyde known as Celcon® from Celanese, which is relatively less responsive to radiolysis under the typical radiochemical sterilization dose (3 to 11 kGy), less than 3 weight percent depolymerized to formaldehyde, and the unused polymer remains in the pouch as an unnecessary component. From a second technological perspective, the present invention provides a preferred alternative to the use of practically pure polyformaldehyde microparticles as the source of formaldehyde, which interferes with the fugacity (or tendency to escape) of the radiolytically formed formaldehyde into the gas phase surrounding the medical device. As the formed formaldehyde migrates through the intact mass of polyformaldehyde, part of it repolymerizes on the surface of the polyformaldehyde particles, thus establishing a monomer-polymer equilibrium that compromises the effectiveness of the radiolytic process. To address this inefficiency, the present invention teaches the use of solid, chemically-unrelated-to formaldehyde particulate dispersant as a thoroughly mixed combination of at least 2:1 weight ratio with a low molecular weight thermodynamically less stable source of formaldehyde, which facilitates the free passages and increases the sterilizing efficiency of the radiolytically formed gas since it (1) does not represent a reactive surface at which the formaldehyde gas can establish a monomer-polymer equilibrium; (2) reduces the required mass of the formaldehyde precursor to produce the sterilizing dose of the gas; and (3) leaves mostly an inert material in the irradiated package—typical dispersants comprise polyethylene, ethylene-propylene copolymer, polypropylene, and polyethylene terephthalate. The polyethylene particles may comprise low density, high density, linear-low density, and/or ultrahigh molecular weight polyethylene (UHMW-PE). From a packaging perspective, the present invention provides two basic advantages over the prior art. First, using a combination of the formaldehyde-precursor and a practically formaldehyde-irrelevant dispersant facilitates the assembling of the porous pouch containing said precursor and insures safe handling by the assembling personnel. Second, the use of desiccant dispersants introduces a unique feature to the packaging technology of medical devices comprising absorbable polymers which undergo detrimental degradation in hermetically sealed packages containing trace amounts of moisture—typical desiccant dispersants include silica gel. In effect, the desiccant dispersant, such as silica gel, not only facilitates the free passage (or diffusion) of the formaldehyde to gas phase of the package, but also absorbs traces of moisture that may have been present, inadvertently, in the package prior to irradiation. Trapping traces of moisture (1) improves the post-irradiation shelf-life of the absorbable solid device; and (2) eliminates or minimizes the radiation-induced conversion of water molecules into hydroxyl radicals in the package, which can lead to additional radiation-oxidation degradation of the absorbable medical device during irradiation, as part of the so called secondary radiation degradation events during or following the irradiation. Third, in packages containing cyanoacrylate-based tissue adhesive, removal of water by the desiccant dispersant eliminates the risk of slow diffusion of water through the walls of the polymeric container housing the cyanoacrylate tissue adhesive, which will undergo premature water-activated polymerization—the use of a desiccant dispersant, such as silica gel, indirectly increases the cyanoacrylate shelf-life.
Further illustrations of the present invention are provided by the following examples:
Example 1
Radiochemical Sterilization (RCS) of Suture Braids Using Different Combinations of Paraformaldehyde and Ultrahigh Molecular Weight Polyethylene (UHMW-PE)
A number of vacuum dried 27 inch lengths of size 2-0 braided sutures were individually placed in a predried, perforated paper folder and placed in groups of 3″×5″ laminated foil packs having a sealed, non-woven polyethylene (Tyvek®) porous pouch filled with different combinations of paraformaldehyde and UHMW-PE (PF-UPE) with an average particle size of >20 micron and <200 micron, respectively, in the presence or absence of a spore strip as an internal control. Descriptions of the different packs are given in Table I. The unsealed foil packs containing the different PF-UPE combinations with and without the spore strip were prepurged twice with dry nitrogen and hermetically sealed. The sealed packs were gamma irradiated with about 5 kGy using a Co-60 source at a dose rate of 32 kGy/hr. The irradiated packs were divided into separate groups and tested at two weeks following irradiation using standard techniques needed to determine (1) the residual formaldehyde in the package; and (2) reduction in spore count of the spore strip. The compositions of the different pouches used in the RCS study of Example 1 are described in Table I. The preparation of the specific groups of pouches is outlined below.
The paraformaldehyde (PF) was purchased from Aldrich in powder form. An UHMW-PE (UPE) was also used a powder with an average particle size of <200 μm. The PF and UPE powders were mixed in three different mass ratios to produce three sets of samples. The first set of samples was based on three different mass ratios of 15/135, 20/130, 25/125, and 30/120 parts paraformaldehyde to UHMW-PE. The second sample set was 5/145 and 10/140 paraformaldehyde to UHMW-PE. Pouches were made using non-woven Tyvek® fabric. A total of 150 mg of each mixture was added to the Tyvek® pouches. The samples made were two repeats for each mixtures pouch type without spore strips and two repeats of each mixtures type with spore strips in the packets.
Details of the formaldehyde testing and response of the spore strips to the prevailing RCS process conditions using the different packages are described in Examples 2 and 3 respectively.
TABLE I
Composition of the Different Packages
Used in the RCS Study of Example I
Pouch No.
Paraformaldehyde, mg
UHMW-PE, mg
I-A
5
145
I-B
10
140
I-C
15
135
I-D
20
130
I-E
25
125
I-F
30
120
Example 2
Testing for Formaldehyde Residue in Packaged Sutures of Example 1 due to Pouches I-A to I-F
The formaldehyde testing method is described below and the respective results are summarized in Table II. For sample preparation, the packets were tipped with silicone for injecting with a syringe. The sample testing consisted of filling the packets with dry nitrogen. The nitrogen and residual formaldehyde was withdrawn through a 60 mL syringe filled with 1 mL of deionized water. The syringe was then shaken for 15 minutes. The water with dissolved residual formaldehyde was transferred into a 2 mL vial. The samples were tested by complexing with dinitrophenylhydrazine (DNPH) and analyzed using HPLC. The samples were compared to an appropriate formaldehyde standard curve using formaldehyde-DNPH condensation products.
TABLE II
Residual Formaldehyde Tested in Packages
Containing Pouches I-A to I-F
Packages with Pouch
Residual Formaldehyde in the
Number.
Package, μg
I-A
26
I-B
26
I-C
29
I-D
29
I-E
28
I-F
30
The data in Table II show practically the same amounts of formaldehyde regardless of net amount of paraformaldehyde and/or its weight relative to the UHMW-PE dispersant. It appears to be virtually dependent only on the radiation dose.
Example 3
Testing for the Effect of the Process of Spore Strips in Packages Containing Four Pouches from Example 1 and a Non-Irradiated Control
The microbiological methods used in determining the effect of the prevailing RCS process on spore strips is described below and respective results are summarized in Table III.
The spore strip was aseptically placed in 50 mL conical tubes with 9 mL of 0.1% Peptone and vortexed for approximately 5 minutes. The vortexed spore strip suspension was poured through a 40-μm-cell strainer, and then rinsed with an additional 1 ml of Peptone. One milliliter of filtered Peptone solution was pipetted onto Tryptic Soy agar plates and swirled gently to obtain full coverage on plate from eluent. For control (non-sterilized) spore strips, serial dilutions were made to reduce the colony forming units (CFU) to a quantifiable amount after incubation. Of the desired concentration, 1 mL was pipetted onto the agar plate. Plates were incubated at 37° C. and checked periodically for 3 days to monitor growth. All samples were tested in duplicate.
TABLE III
Spore Strip Analysis of Radiochemically Sterilized
Packages Containing Pouches from Example 1
Packages with Pouch Number
Colony-forming Units
I-A
0
I-B
0
I-C
0
I-D
0
I-E
0
I-F
0
Non-irradiated Control (an
150*
average of four)
*Expected CFUs = 170.
The data in Table III on sterilization effectiveness of the RCS process under the prevailing conditions and package composition show a parallel behavior to that recorded in the results of Table II. Specifically, 5 to 30 mg of paraformaldehyde can release an almost constant amount of formaldehyde, which is quite effective in achieving a complete spore kill.
Example 4
Radiochemical Sterilization of Absorbable Cyanoacrylate-Based Tissue Adhesive Formulation Using Different Combinations of Paraformaldehyde and Silica Gel
A typical cyanoacrylate-based tissue adhesive formulation was used which contained about 97, 3, <0.5 and <0.05 weight percent of methoxypropyl cyanoacrylate, a polymeric modifier, free radical stabilizer, and anionic stabilizer, respectively. The polymeric modifier comprised an absorbable, aliphatic, segmented polyether-carbonate-urethane. The formulation was packaged under nitrogen atmosphere in sealed polyethylene dispensers (volume=1 mL) with tapered necks. Each dispenser contained 0.4 mL of liquid formulation. Pairs of the dispensers containing the adhesive formulation were placed in groups of 3″×5″ laminated foil packs, each containing a sealed, non-woven polyethylene (Tyvek®) porous pouch filled with different combinations of paraformaldehyde and silica gel as outlined in Table IV. The foil pack containing the tissue adhesive formulation, the porous pouches having the different combinations of paraformaldehyde and silica gel, (average particle size<100 micron) and, in selected cases, a spore strip (for use as a primary control), were purged with nitrogen, heat-sealed, and sterilized under typical RCS conditions as described in Example 1. A number of packages were made without incorporating the pouch for use as secondary controls.
The compositions of the different pouches used in the RCS study of Example 4 are described in Table IV. The preparation of the specific groups of pouches is outlined below. Two sets of packages were prepared. The first and second sets were prepared using 1 to 5 and 1 to 10 weight ratio of paraformaldehyde to silica gel, respectively. The weight of the powder mixture for the first and second set was about 222 and 605 mg, respectively. All packages were purged with nitrogen and sealed. The sealed packages were sterilized by irradiation using about 5 kGy of gamma radiation.
TABLE IV
Composition of Different Packages
Used in the RCS Study of Example 4
Pouch No.
Paraformaldehyde, mg
Silica Gel, mg
II-A
37
185
II-B
55
550
Details of the formaldehyde testing and response of the spore strips to RCS processes using the different package inserts are described in Examples 5 and 6, respectively.
Example 5
Testing for Formaldehyde Residue in Packages II-A and II-B Containing Tissue Adhesives of Example 4
A protocol similar to that described in Example 2 was followed. The respective results are summarized in Table V. The data in Table V indicated no significant dependence of the formaldehyde generation on the amount of paraformaldehyde used.
TABLE V
Residual Formaldehyde Tested in Packages
Containing Pouches II-A and II-B
Residual Formaldehyde at One Week
Packages with Pouch, Number
Post-irradiation in Package, μg
II-A
10
II-B
8
Example 6
Testing the Effect of the RCS Process on Packages Containing Two Types of Pouches from Example 4 and a Non-Irradiated Primary and Pouch-Free Secondary Controls
A protocol similar to that used in Example 3 was followed. The respective results are summarized in Table VI. The data in Table VI indicate that (1) the two packages sterilized under typical RCS conditions exhibited complete spore kill; (2) the pouch-free packages revealed about 20 percent of spore kill compared to the expected value; and (3) the non-irradiated packages showed practically no effect on the spore strips.
TABLE VI
Spore Strip Analysis of Radiochemically Sterilized
Packages Containing Pouches of Example 4 after One
Week Post-irradiation and a Pouch-free Control
Package with and without Pouch
Colony-forming Units at
Number
Two Weeks Post-irradiation
II-A
0
II-B
0
II-C a
143
II-D b
166
a Containing no pouch.
b Control (unsterilized) spore strip expected, CFU = 170.
Although the present invention has been described in connection with the preferred embodiments, it is to be understood that modifications and variations may be utilized without departing from the principles and scope of the invention, as those skilled in the art will readily understand. Accordingly, such modifications may be practiced within the scope of the following claims. Moreover, Applicant hereby discloses all subranges of all ranges disclosed herein. These subranges are also useful in carrying out the present invention. | Package components for the radiochemical sterilization of medical devices contain paraformaldehyde as the precursor of the radiolytically generated, sterilizing dose of formaldehyde, premixed with a particulate solid dispersant of, preferably, polyethylene or silica gel, which facilitates the free passage of the formaldehyde to the package gaseous environment or additionally, absorbs trace amounts of moisture in the package, thus, facilitating the device manufacturing process and increasing shelf-stability. | 1 |
BACKGROUND OF THE INVENTION
[0001] Catheters are often used to form semi-permanent paths into the body so that fluids may be introduced to and removed from the body without repeatedly inserting needles or tubes. For example, a central port catheter is generally used to access the vascular system with a subcutaneous portion of the catheters tunneled from a location of the central port to a remote vessel access location. Thus, the location of the central port may be selected to maximize ease of access, and patient comfort, etc., while the target vessel is accessed at a desired remote location.
[0002] The catheter is generally connected to the central port by inserting a barb extending from the port into a lumen of the catheter with a twist lock being tightened to the port housing to secure the port thereto. However, tightening of the lock adds a step to the procedure and may rotate the catheter around the barb, twisting the catheter body. This twisting may be transmitted to the distal end of the catheter, where it may move the distal end out of a desired positioning within the target vessel.
SUMMARY OF THE INVENTION
[0003] In one aspect, the present invention is directed to a mechanism for locking a catheter to a port, comprising a elongate body defining a flow passage, a port end of the elongate body adapted for attachment to a port, a collet end of the elongate body opposite the port end being biased toward an open configuration in which an in inner diameter of the collet end is sized to receive therein an end of a catheter to be coupled to the port and a tightening device mounted to the elongate body for movement relative thereto between a first position in which the collet end is released to the open configuration and a second position in which the collet end is constricted to a closed configuration in which the inner diameter of the collet end grips the end of the catheter to retain the end of the catheter therewithin.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a perspective view showing a catheter attachment collet lock according to an embodiment of the present invention; and
[0005] FIG. 2 is a cross-sectional perspective view of a catheter attachment collet lock according to a further embodiment of the invention.
DETAILED DESCRIPTION
[0006] The present invention may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The invention is related to medical devices used to withdraw fluids from and/or infuse fluids into the body. More specifically, the invention is related to a device for securely connecting a catheter to a central port.
[0007] As described above, a catheter may be used in conjunction with a central port to facilitate repeated access to blood vessels. Regardless of its use, the central port is designed to be repeatedly connected to and disconnected from an external catheter, which in turn may be connected to an external medical device.
[0008] The connection between a central port and a catheter is conventionally formed by pushing an open end of the catheter over a barb extending from the port with a passage in the barb providing fluid communication between a lumen of the catheter and a flow passage of the port.
[0009] A catheter attachment apparatus and method according to the present invention eliminates the twisting and displacement common with conventional locks. In addition, the locking device according to the invention eliminates the difficulties inherent in handling the multiple parts that form current twist locks, by providing a lock more integrated with the central port. The attachment procedure is thus simplified as securing the catheter to the outlet of the port does not displace the distal tip and the integrated locking device is easier to handle, since there are no lose parts that may be dropped or misplaced.
[0010] The embodiments of the present invention comprise an attachment collet that is fastened to the inlet/outlet of a central port, facing the catheter. The attachment collet is designed to receive one end of the catheter and to compress it, thereby mechanically retaining it therewithin. For example, the catheter may be retained against the collet by friction. A barb may extend from the port along the centerline of the attachment collet, to receive the end of the catheter. The attachment collet, in that case, compresses the catheter between an inner surface of the collet and an outer surface of the barb, to mechanically retain the catheter in place so that fluids may flow from a lumen of the catheter through a passage in the barb to the port.
[0011] FIG. 1 shows an exemplary embodiment of a catheter attachment collet lock 100 for a central port according to the present invention. The collet lock 100 comprises two principal portions: a collet 104 and a thumb wheel 102 . The collet 104 is formed of an elongated tubular body having a port end 106 that can be secured to an inlet or outlet opening of the central port by conventional means such as, for example, an adhesive or mechanical connection. An internal lumen of the collet 104 has a minimum inner diameter sufficient to receive the barb, while providing sufficient flow area to convey a fluid therethrough.
[0012] An opposite end 108 of the collet 104 , which flares outwardly when in an unconstrained open configuration, is formed of a plurality of jaws 122 separated by slots 124 . The flared opposite end 108 be squeezed to a closed configuration having a reduced inner diameter by application of an inwardly directed radial force. The jaws 122 are biased toward the increased diameter open configuration. However, when compressed by a radially inward force, the jaws 122 flex inward to abut one another in closed configuration. The opening 110 is designed to receive therein an end of a catheter when in the open configuration. After the catheter end has been inserted therein, the opening 110 is closed down to the reduced diameter, closed configuration by actuating a tightening device to lock the catheter in place on the central port.
[0013] In one exemplary embodiment, the flared end 108 of the collet 104 is squeezed by a tightening device such as a thumb wheel 102 , in order to reduce the diameter of the opening 110 . For example, an external surface of the collet 104 may comprise threads 120 matching corresponding threads on an inner surface of the thumb wheel 102 , to form a threaded interface between the two components. The thumb wheel 102 may optionally comprise grooves 114 to facilitate gripping of the device and turning of the thumb wheel 102 . With this threaded interface, as the thumb wheel 102 is rotated about the collet 104 in a first direction, it advances towards the flared end 108 of the collet 104 , causing the collet 104 to collapse to the reduced diameter configuration. Rotating the thumb wheel 102 about the collet 104 in a second direction moves the thumb wheel 102 away from the flared end 108 allowing the jaws 122 to spring outward to the increased diameter configuration. As the thumb wheel 102 rotates around the collet 104 and locks the catheter to the collet 104 without any relative rotation of the collet 104 and the catheter, the catheter is not twisted by the locking procedure.
[0014] Those skilled in the art will understand that the threads 120 and the corresponding threads of the thumb wheel 102 may be right handed or left handed. In the latter case, when the user turns the thumb wheel 102 clockwise relative to the collet 104 , the thumb wheel is advanced toward the flared end 108 (i.e., toward the reduced diameter configuration). Using left handed threading for the thumb wheel 102 thus results in a more natural motion to tighten the collet 104 over the catheter, further simplifying the procedure. Furthermore, those skilled in the art will understand that the thumb wheel 102 may be replaced by any conventional apparatus for tightening the collet 104 over the catheter.
[0015] A mechanical stop may optionally be incorporated on the collet 104 to prevent the thumb wheel 102 from becoming detached from the collet lock 100 . For example, a positive stop 112 may be formed at the lip of the collet 104 , to mechanically prevent the thumb wheel 102 from being advanced too far along the collet 104 . In that way, the collet lock 100 remains a single piece, securely attached to the central port. The procedure is therefore simplified, since there are no separate parts of the locking mechanism that can fall or be misplaced during attachment of the catheter or after the catheter has been secured in place. According to the invention, once the catheter has been inserted into the collet 104 , there are no parts that need to be assembled to secure the catheter to the port.
[0016] According to exemplary embodiments of the invention, the inner diameter of the collet 104 , both in the increased and reduced diameter configurations, is selected to prevent damage to the catheter. For example, the collapsed inner diameter is preferably chosen to prevent tightening of the collet 104 to a degree that the structural integrity of the catheter is threatened. At the same time, the collapsed inner diameter of the collet 104 must be sufficiently small that, when closed around the catheter, the collet 104 closes down with sufficient force to prevent leaks between the collet 104 and the catheter and to prevent undesired movement of the catheter relative to the port. A port with no inner barb may be connected to a catheter using the device according to the invention when a sufficient contact area and force between the collapsed collet 104 and the catheter is provided. Since it is difficult to slide the catheter over the barb, removing the barb further simplifies forming the connection of the catheter to the central port.
[0017] FIG. 2 shows a catheter attachment collet lock 200 according to a further embodiment of the present invention. The collet lock 200 is constructed substantially similarly to the collet lock 100 except for a detent projection 202 extending from the distal end(s) of one or more jaws 122 . A profile of each of the detent projections 202 preferably substantially matches a profile of a detent recess 206 formed at a distal end of the barb. Thus, when the jaws 122 are forced radially inward compressing a portion of a catheter received between an inner surface of the jaws 122 and an outer surface of the barb, the detent projection(s) 202 will urge portions of the wall of the catheter into the detent recess to further secure the catheter within the collet lock 200 . Those skilled in the art will understand that the collet lock 200 preferably includes a thumb wheel 102 as described above for securing the catheter within the collet lock 200 and for releasing the catheter therefrom.
[0018] The present invention has been described with reference to specific embodiments, and more specifically to catheter attachment collet used for a central port. However, other embodiments may be devised that are applicable to other types of catheters and ports. Accordingly, various modifications and changes may be made to the embodiments, without departing from the broadest spirit and scope of the present invention as set forth in the claims that follow. The specification and drawings are accordingly to be regarded in an illustrative rather than restrictive sense. | A mechanism for locking a catheter to a port comprises an elongate body defining a flow passage, a port end of the elongate body adapted for attachment to a port, a collet end of the elongate body opposite the port end being biased toward an open configuration in which an in inner diameter of the collet end is sized to receive therein an end of a catheter to be coupled to the port and a tightening device mounted to the elongate body for movement relative thereto between a first position in which the collet end is released to the open configuration and a second position in which the collet end is constricted to a closed configuration in which the inner diameter of the collet end grips the end of the catheter to retain the end of the catheter therewithin. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a divisional of and claims priority to U.S. application Ser. No. 11/728,433, filed Mar. 26, 2007; which is a continuation, under 35 U.S.C. § 120, of International Application No. PCT/EP2005/010031, filed Sep. 16, 2005; this application also claims the priority, under 35 U.S.C. § 119, of German Patent Application No. DE 10 2004 046 558.4, filed Sep. 24, 2004; the prior applications are herewith incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a transmission configuration and a method for controlling a transmission. More specifically, the invention relates to a sensor configuration for an automated dual-clutch transmission with two transmission sections, each having a motor clutch connected on a motor side thereof, via a drive shaft, to a drive motor, an input shaft connected to the motor clutch on a transmission side thereof, and gear wheel sets forming a group of gear stages and each including a fixed gear and an idler gear, wherein a connection with a gear ratio between the input shaft and an output shaft can be established with the gear stages by in each case engaging a gear clutch assigned to the idler gear, wherein the output shaft forms a power take-off shaft connected to an axle drive or wherein the output shaft is permanently connected to such a power take-off shaft, and with a sensor configuration with at least a drive-side speed sensor unit disposed at the drive shaft, a first input-side speed sensor unit disposed at the input shaft of a first one of the transmission sections, and a second input-side speed sensor unit disposed at the input shaft of the second one of the transmission sections, wherein the input-side speed sensor units include a respective sensor wheel connected, fixed against relative rotation, to a respective one of the input shafts and a respective pulse sensor disposed stationary with respect to a housing and within an effective range of the respective sensor wheel. The invention furthermore relates to a method for controlling such an automated dual-clutch transmission.
The dual-clutch transmission has been known for quite a while as a transmission concept and is for example disclosed in German Patent Application Publication No. DE 35 46 454 A1, however, in practice it has been available in the form of an automated dual-clutch transmission only recently in some production passenger vehicles. The dual-clutch transmission includes a first transmission section with a first input shaft, wherein a first motor clutch and in most cases several gearwheel sets, which each form a gear stage, are assigned to the first input shaft and includes a second transmission section with a second input shaft, wherein a second motor clutch and several gearwheel sets, which form further gear stages, are assigned to the second input shaft. On the output side, the dual-clutch transmission can have a common output shaft, which is connected to the gearwheel sets of both transmissions sections or can be connected to them and, in this case, forms a power take-off shaft connected to the axle drive of a driven vehicle axle. In order to achieve an installation length that is as short as possible, which is in particular important in case of a transverse mounting of the drive unit, which is formed of the drive motor and the dual-clutch transmission, it is however also possible for the transmission sections of the dual-clutch transmission to have respective separate output shafts, which are disposed in a V-shape about the input shafts, which are usually disposed coaxial with respect to one another, wherein the output shafts are connected, via a power take-off gearing, with a common power take-off shaft. In case of such a dual-clutch transmission, the shift process between two gear stages, i.e. between an engaged load gear stage and a target gear stage to be engaged, which are assigned to different transmission sections, includes first engaging the target the gear stage, which usually is accomplished with a gear clutch, which is assigned to an idler gear of the corresponding gear stage and can be actuated via a shift collar, and subsequently, in a time-overlapping manner, separating the motor clutch assigned to the input shaft of the load the gear stage and closing the motor clutch assigned to the input shaft of the target gear stage. As a result, the power transmission is accomplished in a respective alternating manner via the first and the second input shaft and is not interrupted during the shift process, which is why the dual-clutch transmission falls in the category of power shift transmissions. In order to perform as many shift processes as possible in the described manner, the gear stages are assigned in an alternating manner to the two transmission sections, i.e. one transmission section includes the odd forward gear stages and the other transmission section includes the even forward gear stages.
Since the actuation of the two motor clutches, in particular the time-overlapping actuation, in such a shift process is extremely complex and cannot be accomplished with an acceptable mechanical outlay in a manual-mechanical manner, the conventional dual-clutch transmissions are embodied as automated transmissions and have several controllable actuators for actuating the motor clutches and the gear clutches as well as several speed sensor units for ascertaining required speed information and information related to a direction of rotation. As is for example disclosed in German Patent Number Nos. DE 199 39 818 C1 and DE 199 39 819 C1, conventional dual-clutch transmissions have at least one drive-side speed sensor unit disposed at the drive shaft, a first input-side speed sensor unit disposed at the first input shaft of the first transmission section and a second input-side speed sensor unit disposed at the second input shaft of the second transmission section, and a speed sensor unit on the power take-off side, which is in most cases embodied speed sensitive and sensitive to a direction of rotation and is disposed at a power take-off shaft, which is connected to an axle drive or at an output shaft which is permanently connected to the power take-off shaft. The drive-side speed sensor unit and the two input-side speed sensor units provide the speed on the motor side and, respectively, on the transmission side of the two motor clutches and are therefore mainly used for controlling the two motor clutches. The speed sensor unit on the power take-off side provides the speed and the direction of rotation of the power take-off shaft connected to the axle drive and is in particular used during driving-off processes for ascertaining the state of motion of the concerned motor vehicle, i.e. detecting a forward movement, a stopping of the vehicle, a backwards movement and the value of the movement speed. The speed sensor unit on the power take-off side is furthermore also used for diagnostic purposes such as a checking a plausibility of the effective gear ratio and monitoring the speed of the drive shaft.
A disadvantage of this sensor configuration is however the large number of speed sensor units that is used and in particular the spatial distance between the speed sensor unit on the power take-off side and the other speed sensor units. The high number of speed sensor units results in relatively high costs for purchasing, mounting and wiring as well as corresponding fault possibilities during operation. Due to the spatial distance of the speed sensor unit on the power take-off side, it is practically impossible to combine all speed sensor units in a module that can be pre-assembled so that they can be installed together. The placement of the speed sensor unit on the power take-off side at the power take-off shaft or an output shaft connected to the power take-off shaft is unfavorable with respect to the signaling system because these shafts have a relatively small speed which results in a reduced temporal resolution of the associated sensor signals and thus results in a delayed detection of a movement of the motor vehicle. As is disclosed in German Patent Application Publication No. DE 103 08 218 A1, this deficiency can be remedied by an additional evaluation of the sensor signal of a simple drive-side speed sensor unit disposed at a faster rotating gear shaft. However, this requires an increased outlay with respect to system and process engineering.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a transmission configuration and a method for controlling a transmission which overcome the above-mentioned disadvantages of the heretofore-known methods and configurations of this general type. It is in particular an object of the invention to provide a transmission configuration whose sensor configuration is cost-effective and saves space and allows performing typical control functions of a dual-clutch transmission without limitations or restrictions. Another object of the invention is to provide a method for controlling a transmission which allows performing typical control functions of a dual-clutch transmission with a reduced number of speed sensor units.
With the foregoing and other objects in view there is provided, in accordance with the invention, a transmission configuration, including:
a drive shaft configured to be connected to a motor;
an automated dual-clutch transmission including a housing and two transmission sections with respective input shafts, respective output shafts and respective motor clutches, the motor clutches having a motor side and a transmission side, and the motor clutches being connected to the drive shaft on the motor side of the motor clutches and being connected to a respective one of the input shafts on the transmission side of the motor clutches;
an axle drive;
each of the transmission sections including gearwheel sets, the gearwheel sets forming a respective group of gear stages and having respective fixed gears and respective idler gears;
each of the transmission sections including gear clutches assigned to the idler gears such that, when a given one of the gear clutches assigned to a given one of the idler gears is engaged, a respective one of the input shafts is connected to a respective one of the output shafts with a given gear ratio, and the respective one of the output shafts is operatively connected to the axle drive;
a drive-side speed sensor unit disposed at the drive shaft; and
an input-side speed sensor configuration including a first sensor wheel connected, fixed against relative rotation, to a first one of the input shafts, a second sensor wheel connected, fixed against relative rotation, to a second one of the input shafts, a first pulse sensor disposed stationary with respect to the housing and within an effective range of the first sensor wheel, and a second pulse sensor disposed stationary with respect to the housing and within an effective range of the second sensor wheel, the input-side speed sensor configuration being configured to detect a speed of the input shafts and a direction of rotation of at least one of the input shafts, the drive-side speed sensor unit and the input-side speed sensor configuration forming a sensor configuration for controlling the automated dual-clutch transmission.
In accordance with another feature of the invention, the first sensor wheel and the first pulse sensor form a first input-side speed sensor unit, the first input-side speed sensor unit is sensitive to speed and sensitive to a direction of rotation, the second sensor wheel and the second pulse sensor form a second input-side speed sensor unit.
In accordance with another feature of the invention there is provided, a power take-off shaft connected to the axle drive, the respective one of the output shafts is operatively connected to the axle drive by being permanently connected to the power take-off shaft.
In accordance with a further feature of the invention, the respective one of the output shafts which is operatively connected to the axle drive forms a power take-off shaft connected to the axle drive.
In accordance with yet another feature of the invention, the first sensor wheel is a rotary-direction encoded sensor wheel and the first pulse sensor is a simple pulse sensor.
In accordance with another feature of the invention, the drive-side speed sensor unit disposed at the drive shaft includes a pulse sensor; and the first pulse sensor, the second pulse sensor, and the pulse sensor of the drive-side speed sensor unit are combined in a pre-assembled module in order to be installed together.
In other words, according to the invention, there is provided a sensor configuration for controlling an automated dual-clutch transmission with two transmission sections, each having a motor clutch connected on a motor side thereof, via a drive shaft, to a drive motor, an input shaft connected to the motor clutch on a transmission side thereof, and gear wheel sets forming a group of gear stages and each including a fixed gear and an idler gear, wherein a connection with a gear ratio between the input shaft and an output shaft can be established with the gear stages by in each case engaging a gear clutch assigned to the idler gear, wherein the output shaft forms a power take-off shaft connected to an axle drive or wherein the output shaft is permanently connected to such a power take-off shaft, with at least a drive-side speed sensor unit disposed at the drive shaft, a first input-side speed sensor unit disposed at the first input shaft of the first transmission section, and a second input-side speed sensor unit disposed at the second input shaft of the second transmission section, each input-side speed sensor unit including a sensor wheel connected, fixed against relative rotation, to a respective input shaft and a pulse sensor disposed stationary with respect to a housing and within an effective range of the sensor wheel, characterized in that a speed sensor unit, which is speed sensitive and sensitive to a direction of rotation, is disposed at least at an input shaft of one of the two transmission sections.
As will be explained in more detail below, it is possible to accomplish typical control functions of the dual-clutch transmission for which so far the speed sensor unit on the power take-off side was needed, by using the input-side speed sensor unit according to the invention, which is speed sensitive and sensitive to a direction of rotation, and it is possible to accomplish the control functions with an even better temporal resolution due to the increased rotational speed of the input shaft. This allows either to eliminate the speed sensor unit on the power take-off side or to increase the operational reliability of the transmission control by performing the appropriate control functions in case of a defect of one of the two speed sensor units, which are speed sensitive and sensitive to a direction of rotation, in each case by the respective other speed sensor unit.
The new speed sensor unit, which is speed sensitive and sensitive to a direction of rotation, is preferably realized by a corresponding embodiment of one of the input-side speed sensor units that are already present in order to avoid a further, separate speed sensor unit. In other words, one of the two input-side speed sensor units is configured to be speed sensitive and sensitive to a direction of rotation.
The speed sensor unit that is sensitive to speed and to a direction of rotation, is preferably formed by a sensor wheel that is encoded with respect to a direction of rotation (rotary encoder wheel) and a simple pulse sensor, whose general concept is in principle known, because this type of construction is especially cost-effective and space saving and requires only one signal line.
In particular when saving the speed sensor unit on the power take-off side, it is possible to advantageously combine the pulse sensors of the drive side speed sensor unit and the two input-side speed sensor units and, if applicable, also an additional input-side speed sensor unit, which is sensitive to speed and sensitive to a direction of rotation, in a pre-assembled module that can be installed together.
With the objects of the invention in view there is also provided, a method for controlling a transmission, which includes the steps of providing an automated dual-clutch transmission with two transmission sections, each having a motor clutch connected on a motor side thereof, via a drive shaft, to a drive motor, an input shaft connected to the motor clutch on a transmission side thereof, and gear wheel sets forming a group of gear stages and each including a fixed gear and an idler gear, wherein a connection with a gear ratio between the input shaft and an output shaft can be established with the gear stages by in each case engaging a gear clutch assigned to the idler gear, wherein the output shaft forms a power take-off shaft connected to an axle drive or wherein the output shaft is permanently connected to such a power take-off shaft, and with a sensor configuration with at least a drive-side speed sensor unit disposed at the drive shaft, a first input-side speed sensor unit disposed at the input shaft of a first one of the transmission sections, and a second input-side speed sensor unit disposed at the input shaft of the second one of the transmission sections; and determining a speed and a direction of rotation of the power take-off shaft by using an input-side speed sensor unit which is speed sensitive and sensitive to a direction of rotation, by first, with an opened motor clutch, engaging a gear stage of a transmission section including the input-side speed sensor unit, by ascertaining, with the input-side speed sensor unit, a speed and a direction of rotation of the input shaft of a respective transmission section, and by subsequently calculating a speed and a direction of rotation of the power take-off shaft from the speed and the direction of rotation of the input shaft with a gear ratio and, if applicable, a reversal of a direction of rotation of an engaged gear stage.
This allows to reliably ascertain the speed and the direction of rotation of the power take-off shaft while avoiding a signal evaluation of the speed sensor unit on the power take-off side, wherein expediently the smallest gear stage of the respective transmission section is engaged in order to achieve a greatest possible temporal resolution of the rotational motion of the power take-off shaft. The method according to the invention, which is mainly used in a driving-off process in order to determine a vehicle movement, such as a forward movement of the vehicle, a stopping of the vehicle, a backward movement of the vehicle and a movement speed, can thus be used for saving, i.e. eliminating, the speed sensor unit on the power take-off side or, if desired, for increasing the operational reliability as a backup method in case of a defect of the speed sensor unit on the power take-off side.
In case of assigning the speed sensor unit that is speed sensitive and sensitive to a direction of rotation to the transmission section that includes the driving-off gear stage, it is expedient to engage the driving-off gear stage in a driving-off process for ascertaining the vehicle movement.
However, if the driving-off occurs with a driving-off gear stage of the other transmission section, then, in order to ascertain the vehicle movement, a gear stage is engaged as an auxiliary gear stage in the transmission section that includes the speed sensor unit that is speed sensitive and sensitive to a direction of rotation, in order to establish a connection to the power take-off shaft.
After finishing the driving-off process, the auxiliary gear stage is again disengaged if in a directly subsequent shift process a different gear stage is provided as a target gear stage. The auxiliary gear stage can however advantageously remain engaged if it is provided as a target gear stage in a directly subsequent shift process.
With the objects of the invention in view there is also provided a method for controlling a transmission, which includes the steps of providing an automated dual-clutch transmission with two transmission sections, each having a motor clutch connected on a motor side thereof, via a drive shaft, to a drive motor, an input shaft connected to the motor clutch on a transmission side thereof, and gear wheel sets forming a group of gear stages and each including a fixed gear and an idler gear, wherein a connection with a gear ratio between the input shaft and an output shaft can be established with the gear stages by in each case engaging a gear clutch assigned to the idler gear, wherein the output shaft forms a power take-off shaft connected to an axle drive or wherein the output shaft is permanently connected to such a power take-off shaft, and with a sensor configuration with at least a drive-side speed sensor unit disposed at the drive shaft, and an input-side speed sensor unit disposed at the input shaft of one of the two transmission sections; and determining a speed of the input shaft of one transmission section by using an input-side speed sensor unit of another transmission section, by first, with a respective engaged gear stage in both transmission sections, ascertaining, with the input-side speed sensor unit, a speed of the input shaft of the other transmission section and by subsequently calculating the speed of the input shaft of the one transmission section from the ascertained speed with the gear ratios of both engaged gear stages.
In a similar manner it is also possible to determine a direction of rotation of the input shaft of the one transmission section with the input-side speed sensor unit of the other transmission section, that is configured to be sensitive to a direction of rotation, by first, with a respective engaged gear stage in both transmission sections, ascertaining, with this input-side speed sensor unit, a direction of rotation of the input shaft of the other transmission section and by subsequently calculating the direction of rotation of the input shaft of the one transmission section from the direction of rotation with the changes in a direction of rotation of the gearwheel sets of both engaged gear stages. In this case, however, in contrast to the above-described determination of the speed of the input shaft of the one transmission section, it is necessary to configure the applicable input-side speed sensor unit such that it is sensitive to the direction of rotation.
With the described procedure it is possible to determine the speed and the direction of rotation of the input shaft of that transmission section whose input-side speed sensor is not used, while avoiding a signal evaluation of the speed sensor unit on the power take-off side as well as one of the two input-side speed sensor units. The method according to the invention, which is mainly used for a sequential shift process, i.e. in the present case a shift process between a load gear stage of the other transmission section and a target gear stage of the one transmission section, can thus alternatively be used as a backup method in case of a defect in one of the two input-side speed sensor units for increasing the operational reliability and for eliminating one of the two input-side speed sensor units.
Since in a sequential shift process the motor clutch of the transmission section that includes the target gear stage is closed by using a control, whereas the motor clutch of the transmission section including the load gear stage is in most cases opened without using a control, it is desirable to know the speed of the input shaft of the transmissions section that includes the target gear stage until the end of the shift process, i.e. until a complete closing of the concerning motor clutch occurs. Therefore, in case of a shift process, in which only the sensor signal of the input-side speed sensor unit of the transmission section that includes the load gear stage is used, the load gear stage remains expediently engaged until the motor clutch assigned to the target gear stage is completely closed. In other words, a mode of the invention includes, in case of a shift process between a load gear stage assigned to the other transmission section and a target gear stage assigned to the one transmission section, leaving the load gear stage engaged until a motor clutch assigned to the target gear stage is completely closed for determining a speed and/or a direction of rotation of the input shaft of the one transmission section by using the input-side speed sensor unit of the other transmission section.
The method according to the invention can however also be used, in a driving-off process with the driving-off gear stage of the one transmission section, for determining the speed of the assigned input shaft with the input-side speed sensor unit of the other transmission section, if a gear stage is engaged as an auxiliary gear stage in the other transmission section. In other words, a mode of the invention includes, in case of a driving-off process with a driving-off gear stage of the one transmission section, engaging a gear stage in the other transmission section as an auxiliary gear stage for determining a speed and/or a direction of rotation of the respective input shaft by using the input-side speed sensor unit of the other transmission section.
In this case, a gear stage, which is the next higher gear stage with respect to the driving-off gear stage of the one transmission section, is engaged as an auxiliary gear stage, because this gear stage is with a high probability the target gear stage of a shift process directly subsequent to the driving-off process.
With the objects of the invention in view there is also provided a method for controlling a transmission, which includes the steps of providing an automated dual-clutch transmission with two transmission sections, each having a motor clutch connected on a motor side thereof, via a drive shaft, to a drive motor, an input shaft connected to the motor clutch on a transmission side thereof, and gear wheel sets forming a group of gear stages and each including a fixed gear and an idler gear, wherein a connection with a gear ratio between the input shaft and an output shaft can be established with the gear stages by in each case engaging a gear clutch assigned to the idler gear, wherein the output shaft forms a power take-off shaft connected to an axle drive or wherein the output shaft is permanently connected to such a power take-off shaft, and with a sensor configuration with at least a drive-side speed sensor unit disposed at the drive shaft, a first input-side speed sensor unit disposed at the input shaft of a first one of the transmission sections, and a second input-side speed sensor unit disposed at the input shaft of the second one of the transmission sections; and determining, in case of an external synchronization of the gear stages in a shift process between a load gear stage assigned to the first one of the transmission sections and a target gear stage assigned to the second one of the transmission sections, an output-side speed of the gear clutch of the target gear stage with the first input-side speed sensor unit of the first one of the transmission sections, by first ascertaining, with the first input-side speed sensor unit, a speed of the input shaft of the first one of the transmission sections and by subsequently calculating from the ascertained speed with an effective transmission ratio between the respective input shaft and the gear clutch of the target gear stage, an output-side speed of the gear clutch of the target gear stage.
For an external synchronization of the gear stages, which is for example accomplished via auxiliary drives which are connected to the input shafts of the transmission sections, it is necessary to know the speeds on both sides of the respective gear clutch, i.e. the input-side speed and the output-side speed. The input-side speed of the gear clutch is in this case usually determined through the use of the input-side speed sensor unit of the same transmission section, wherein, in case the gear clutch is arranged on the output shaft, a conversion with the gear ratio of the concerned gear stage is performed. The output-side speed of the gear clutch can however be determined in accordance with the invention through the use of the input-side speed sensor unit of the other transmission section, while avoiding a signal evaluation of the speed sensor unit on the power take-off side, in that the determined speed of the input shaft of this sensor unit is calculated back with the effective transmission ratio between this input shaft and the gear clutch of the target gear stage, wherein this gear ratio, in case the concerned gear clutch is disposed on the output shaft, corresponds to the gear ratio of the load gear stage and, in case it is disposed on the input shaft, corresponds to the quotient of the gear ratios of the load gear stage and the target gear stage.
Other features which 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 dual-clutch transmission configuration and a method for controlling a dual-clutch transmission, it is nevertheless not intended to be limited to the details shown, since 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 schematic view of a drive train with a dual-clutch transmission and a sensor configuration according to the invention; and
FIG. 2 is a schematic view of a drive train with a dual-clutch transmission and a sensor configuration according to the prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the figures of the drawings in detail and first, particularly, to FIG. 2 thereof, there is shown a conventional drive train 1 of a motor vehicle wherein a dual-clutch transmission 2 is connected on its input side, via a drive shaft 3 and a vibration damper 4 , to a drive motor 5 which is embodied as an internal combustion engine. On its power take-off side, the dual-clutch transmission 2 is connected, via a power take-off shaft 6 , to an axle drive 7 , which transfers a torque, which is generated by the drive motor 5 and which is converted in the dual-clutch transmission, via drive shafts 8 to driven wheels 9 .
The dual-clutch transmission 2 is formed of two transmission sections 10 , 11 , a first transmission section 10 and a second transmission section 11 , which are disposed partly coaxial with respect to one another, however in FIG. 2 they are shown in a schematic exploded view in order to provide a better overview.
The first transmission section 10 includes a first motor clutch 12 , which is connected, on its motor side, to the drive shaft 3 and is connected, on its transmission side, to a first input shaft 13 . The first input shaft 13 is selectively connectable to a first output shaft 18 via one of the several gearwheel sets 14 , 15 , 16 , 17 , each of which constitutes a respective gear stage. The gearwheel sets 14 , 15 , 16 , 17 respectively include a fixed gear 14 a , 15 a , 16 a , 17 a , which is respectively connected, in a manner fixed against relative rotation, to the first input shaft 13 or to the first output shaft 18 , and an idler gear 14 b , 15 b , 16 b , 17 b , which is rotatably mounted on the first output shaft 18 or the first input shaft 13 . The gearwheel sets 14 , 15 , 16 , 17 of the first transmission section respectively form a gear stage, in this case a first forward gear stage G 1 , a third forward gear stage G 3 , a fifth forward gear stage G 5 and a seventh forward gear stage G 7 . The gear stages G 1 , G 3 , G 5 , G 7 can be selectively engaged and disengaged via two shift collars 19 , 20 , each of which being assigned to respective two gear stages, and gear clutches 14 c , 15 c , 16 c , 17 c , which are assigned to respective idler gears 14 b , 15 b , 16 b , 17 b . The first output shaft 18 is permanently in connection with a power take-off shaft 6 via a power take-off gearing 21 a.
The second transmission section 11 includes a second motor clutch 22 , which is connected, on its motor side, to the drive shaft 3 and is connected, on its transmission side, to a second input shaft 23 . The second input shaft 23 is selectively connectable to a second output shaft 28 via one of the several gearwheel sets 24 , 25 , 26 , 27 , each of which constitutes a respective gear stage. The gearwheel sets 24 , 25 , 26 , 27 respectively include a fixed gear 24 a , 25 a , 26 a , 27 a , which is respectively connected, in a manner fixed against relative rotation, to the second input shaft 23 or to the second output shaft 28 , and an idler gear 24 b , 25 b , 26 b , 27 b , which is rotatably mounted on the second output shaft 28 or the second input shaft 23 . The gearwheel sets 24 , 25 , 26 , 27 of the second transmission section form in this case a second forward gear stage G 2 , a fourth forward gear stage G 4 , a sixth forward gear stage G 6 and a reverse gear stage R, which achieves a reversal of the direction of rotation of the second output shaft 28 with respect to the forward gear stages G 2 , G 4 , G 6 by using an intermediate gear 27 d which is provided between the fixed gear 27 a and the idler gear 27 b . The power and smash 27 b . The gear stages G 2 , G 4 , G 6 , R can be selectively engaged and disengaged via two shift collars 29 , 30 , each of which being assigned to respective two gear stages, and gear clutches 24 c , 25 c , 26 c , 27 c , which are assigned to respective idler gears 24 b , 25 b , 26 b , 27 b . The second output shaft 28 is also permanently in connection with a power take-off shaft 6 via a power take-off gearing 21 b.
The power transmission from the drive motor 5 to the axle drive 7 is accomplished alternately via the first transmission section 10 and the second transmission section 11 . A sequential shift process between a load gear stage, for example the third forward gear stage G 3 , of one transmission section 10 and a target gear stage, for example the fourth forward gear stage G 4 , of the other transmission section 11 is accomplished, with gear stages G 3 , G 4 being engaged at the same time, in a time-overlapping control of the two motor clutches 12 , 22 , during which the motor clutch 12 of the load gear stage G 3 is opened and the motor clutch 22 of the target gear stage G 4 is closed without an interruption of the tractive force.
For the control of the two motor clutches 12 , 22 , in particular during driving-off processes and shift processes, the dual-clutch transmission 2 normally includes a sensor configuration 31 with a speed sensor unit 32 on the drive side, that is disposed at the drive shaft 3 , a first speed sensor unit 33 on the input side, that is disposed at the first input shaft 13 , and a second speed sensor unit 34 on the input side, that is disposed at a second input shaft 23 . The conventional sensor configuration 31 includes in this case also a speed sensor unit 35 on the power take-off side, that is disposed at the second output shaft 28 in particular for detecting a vehicle movement during driving-off processes, such as when the vehicle moves forward, stops, moves backwards, and for detecting a movement speed, and for a plausibility check of the respective active gear stage. The speed sensor units 32 , 33 , 34 , 35 , of which the speed sensor unit 35 on the power take-off side is configured to be sensitive to speed and sensitive to the direction of rotation, which is symbolized in the illustration of the speed sensor unit 35 in FIG. 2 by a dividing line, and the remaining speed sensor units 32 , 33 , 34 are configured to be only speed sensitive, are connected, via sensor lines 36 , 37 , 38 , 39 , to an evaluation unit 40 , which is connected to a transmission control device (not shown) or which is a component of the transmission control device. Actuators (not shown) for actuating the motor clutches 12 , 22 and the shift collars 19 , 20 , 29 , 30 are controlled by the transmission control device.
In the drive train 1 shown in FIG. 1 , in an otherwise identical configuration, one of the two speed sensor units 33 , 34 on the input side, is configured to be sensitive to (rotational) speed and to the direction of rotation in accordance with the invention, in the present case the first speed sensor unit 33 ′ on the input side is configured to be sensitive to the speed and to the direction of rotation which is symbolized in the illustration of the speed sensor unit 33 ′ in FIG. 1 by a dividing line. The speed sensor units 33 ′, 34 preferably include sensor wheels (encoder wheels) 53 , 54 and pulse sensors 43 , 44 . As is explained in an exemplary manner in the following, this provides the possibility, to perform typical control functions of the dual-clutch transmission 2 without an evaluation of the sensor signals of the speed sensor unit 35 on the power take-off side and, if applicable, even without an evaluation of the sensor signals of the second speed sensor unit 34 on the input side which is only sensitive to speed. This can optionally be used for saving, i.e. eliminating, the respective speed sensor units 34 , 35 or for maintaining the ability to operate the dual-clutch transmission 2 in case of a defect of these speed sensor units 34 , 35 and consequently for increasing operational reliability of the dual-clutch transmission 2 . A possible elimination or a defect of the respective speed sensor units 34 , 35 is indicated in FIG. 1 by representing the speed sensor units 34 , 35 and the associated sensor lines 38 , 39 in dashed lines.
In accordance with the invention, the speed and the direction of rotation of the power take-off shaft 6 can be determined through the use of the first speed sensor unit 33 ′ on the input side, in that, with the first motor clutch 12 opened, at first, a gear stage G 1 , G 3 , G 5 , G 7 of the first transmission section 10 is engaged, in that the speed and the direction of rotation of the first input shaft 13 is determined through the use of the speed sensor unit 33 ′, and in that subsequently the speed and the direction of rotation of the power take-off shaft 6 is calculated from the speed and the direction of rotation of the input shaft 13 with the gear ratio and (if applicable) a reversal of the direction of rotation of the engaged gear stage G 1 , G 3 , G 5 , G 7 by assigning a reverse gear stage to the first transmission section 10 , which is theoretically possible but not present in this case. In this case, in order to achieve a greatest possible temporal resolution of a rotational motion of the power take-off shaft 6 , whose fast and exact detection is important for determining a vehicle movement in particular in case of a driving-off process, the smallest (lowest) gear stage G 1 is expediently engaged, in other words in the present case the first gear stage G 1 is engaged.
Engaging the first gear stage G 1 for determining the speed and the direction of rotation of the power take-off shaft 6 with the first speed sensor unit 33 ′ on the input side is optimal with respect to the temporal resolution, no matter whether one drives off with the first gear stage G 1 of the first transmission section 10 or the second gear stage G 2 of the second transmission section 11 . In the last mentioned case it may however also be expedient to engage the third gear stage G 3 for determining the speed and the direction of rotation of the power take-off shaft 6 , because this gear stage G 3 has a high probability of being the target gear stage in the directly following shift process and thus it can initially remain engaged after the driving-off process.
Furthermore, the speed of the second input shaft 23 can also be determined with the sensor configuration 31 ′ according to the invention through the use of the first speed sensor unit 33 ′ on the input side, namely by first determining the speed of the first input shaft 13 by means of the speed sensor unit 33 ′ in case of a respective engaged gear stage (G 3 , G 4 ) in both transmissions sections 10 , 11 , and by subsequently calculating the speed of the second input shaft 23 from this speed with the gear ratios of the two engaged gear stages (G 3 , G 4 ). This method can be used for a shift process between a load gear stage of one transmission section and a target gear stage of the other transmission section and can also be used for a driving-off process with a driving-off gear stage of the second transmission section 11 . In case of shifting into a target gear stage (G 4 ) of the second transmission section 11 it is expedient for an exact determination of the speed of the second input shaft 23 to leave the load gear stage (G 3 ) of the first transmission section 10 in its engaged state until the second motor clutch 22 is completely closed. In a driving-off process with a driving-off gear stage, e.g. the second gear stage G 2 , of the second transmission section 11 , a gear stage of the first transmission section 10 is engaged as an auxiliary gear stage for determining the speed of the second input shaft 23 by means of the first speed sensor unit 33 ′ on the input side, wherein expediently the gear stage which is the next higher one to the driving-off gear stage G 2 of the second transmission section 11 is engaged, i.e. in the present case the third gear stage G 3 of the first transmission section 10 .
Finally, in case of an external synchronization of the gear stages in a shift process between a load gear stage G, G 3 , G 5 , G 7 , which is assigned to the first transmission section 10 , and a target gear stage G 2 , G 4 , G 6 , R, which is assigned to the second transmission section 11 , the method according to the invention can also be used to determine the speed of the gear clutch 24 c , 25 c , 26 c , 27 c on the output-side by means of the first speed sensor unit 33 ′ on the input side. This is done by first determining the speed of the first input shaft 13 with the speed sensor unit 33 ′, and by subsequently calculating from this speed the speed on the output-side of the gear clutches 24 c , 25 c , 26 c , 27 c of the target gear stage G 2 , G 4 , G 6 , R with the effective gear ratio between the respective input shaft 13 and the gear clutch 24 c , 25 c , 26 c , 27 c of the target gear stage G 2 , G 4 , G 6 , R.
LIST OF REFERENCE NUMERALS
1
drive train
2
dual-clutch transmission
3
drive shaft
4
vibration damper
5
drive motor
6
power take-off shaft
7
axle drive
8
drive shaft
9
wheel
10
(first) transmission section
11
(second) transmission section
12
(first) motor clutch
13
(first) input shaft
14, 15, 16, 17
gearwheel set
14a, 15a, 16a, 17a
fixed gear
14b, 15b, 16b, 17b
idler gear
14c, 15c, 16c, 17c
gear clutch
18
(first) output shaft
19, 20
shift collar
21a, 21b
power take-off gearing
22
(second) motor clutch
23
(second) input shaft
24, 25, 26, 27
gearwheel set
24a, 25a, 26a, 27a
fixed gear
24b, 25b, 26b, 27b
idler gear
24c, 25c, 26c, 27c
gear clutch
27d
intermediate gear
28
(second) output shaft
29, 30
shift collar
31, 31′
sensor configuration
32
drive-side speed sensor unit
33, 33′
(first) input-side speed sensor unit
34
(second) input-side speed sensor unit
35
speed sensor unit on the power take-off side
36, 37, 38, 39
sensor line
40
evaluation unit
43, 44
pulse sensor
53, 54
sensor wheel
G1-G7
(forward) gear stage
R
(reverse) gear stage | A transmission configuration includes an automated dual-clutch transmission having two transmission sections with respective input shafts, respective output shafts and respective motor clutches. The motor clutches are connected, on a motor side thereof, to a drive shaft and to a respective one of the input shafts on a transmission side thereof. A drive-side speed sensor unit is disposed at the drive shaft. An input-side speed sensor configuration includes sensor wheels connected, fixed against relative rotation, to respective ones of the input shafts, and pulse sensors disposed stationary with respect to a housing and within an effective range of the respective sensor wheels. The input-side speed sensor configuration is configured to detect a speed of the input shafts and a direction of rotation of at least one of the input shafts. A method for controlling an automated dual-clutch transmission is also provided. | 5 |
FIELD OF THE INVENTION
The present invention relates to a method for preparing a direct positive silver halide emulsion, which has been fogged in advance, specifically, a direct reversal type silver halide light-sensitive emulsion, which is used for a black-and-white light-sensitive material and has an improved photographic performance, including high sensitivity and high contract.
BACKGROUND OF THE INVENTION
The silver halide emulsion used for the direct positive silver halide photographic light-sensitive material according to the present invention is fogged in advance, and a solarization or a Herschel effect is utilized to break fogging nuclei by exposure, whereby a positive image is formed. The direct positive light-sensitive material can include a photographic light-sensitive material having a high sensitivity, in which a desensitizing dye is used, as shown in JP-B-50-3938 (the term "JP-B" as used herein means an examined Japanese patent publication) and JP-B-50-3937, and a light-sensitive material for daylight which can be handled in the daylight, as shown in JP-A-62-234156 (the term "JP-A" as used herein means an unexamined Japanese patent application) and JP-A-61-251843. The present invention relates to the silver halide emulsion used for these light-sensitive materials.
Usually, a direct positive type light-sensitive material is fogged with a reducing agent after the formation of the grains so that a reduced Ag nucleus is formed on the surface thereof to the extent that optical bleaching is possible. Obtaining the performance of high sensitivity and high contrast requires suppressing the degree of fogging and equalizing fogging among the grains. However, suppressing the degree of fogging to increase sensitivity makes it difficult to increase Dmax and softens gradation.
Suppressing the degree of fogging in order to suppress Dmin may result in a Dmax which is not sufficiently increased and a gradation which is liable to become soft.
Further, in a direct positive light-sensitive material for photographing, since it is required to increase sensitivity, the degree of fogging by a reducing agent can not be strengthened and, therefore, the resulting Ag nuclei are fine and unstable.
Meanwhile, in a direct positive light-sensitive material for daylight, the need for a decrease in sensitivity requires an intensification of the degree of fogging with a reducing agent and, therefore, the resulting Ag nuclei are not easily bleached by exposure and the Dmin is liable to increase.
It is proposed in JP-B-50-3978 to use a gold compound to increase stability of the Ag nuclei. However, even the use of a gold compound does not overcome the fact that the Ag nuclei remain insufficiently stable and Dmin is liable to increase.
Further, the development processing of the direct positive light-sensitive material has been carried out by a lith development (for example, HS-5 (developer) manufactured by Fuji Photo Film Co., Ltd.). In recent years, however, the trend for a processing system has been changed. That is, a rapid processing aptitude such as an RAS (a rapid access) processing and Hybrid processing (for example, Grandex manufactured by Fuji Photo Film Co. and Ultratec manufactured by Eastman Kodak Co., Ltd.) have been required. Thus, it is desired to achieve excellent performance with respect to Dmax, Dmin and high contrast as close as possible to those achieved with the lith processing.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a method for preparing a direct positive silver halide emulsion having a high sensitivity, capable of providing high Dmax, low Dmin and a high contrast. Another object of the present invention is to provide a method for preparing a direct positive silver halide emulsion having good storage performances.
The above objects and advantages have been obtained by the following method.
A method for preparing a fogging type direct positive silver halide emulsion comprising the steps of:
(a) forming an emulsion containing silver halide grains;
(b) fogging surfaces of the grains with a reducing agent to form a silver nuclei; and then
(c) performing at least one of an adjustment of pH of the emulsion to 4.5 or less and an adjustment of pAg of the emulsion to 8.1 or more.
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, the preparation of the direct positive emulsion can be divided into three steps which occur after the ripening step which, in turn, occurs after the grain formation and precipitating-washing steps. The first step is a fogging step, the second one is a bleaching step and the third step is a stabilizing step. The respective steps will be explained below.
The direct positive type silver halide used in the present invention may be fogged by a known technique after removing the water soluble salts generated after precipitating the silver halide. Fogging may be provided either singly with a fogging agent (a reducing agent) or with a combination of a fogging agent, gold compound and a metal compound useful for stabilizing and improving photographic performances (e.g., Dmax, sensitivity, Dmin), which is electrically more positive than silver.
Generally, the fogging is conducted in a 0.5 to 15% preferably 1% to 10% aqueous gelatin solution.
The fogging agent useful for preparing the emulsion include, for example, formalin, hydrazine, a polyamine (e.g., triethylenetetramine and tetraethylenepentamine), thiourea dioxide, tetra(hydroxymethyl) phosphonium chloride, amine borane, a boron hydride compound, stannous chloride, and tin (II) chloride, and examples of the metal compound which is electrically more positive than silver include, soluble salts of gold, rhodium, palladium, and iridium, such as, potassium chloraurate, chlorauric acid, sodium chloraurate, gold sulfide, and gold selenide, ammonium palladium chloride, and sodium iridium chloride.
In general, the fogging agent is used in the ranging from 1.0×10 -6 to 1.0×10 -1 mole, preferably 5×10 -6 to 5×10 -2 mole per mole of silver halide.
In general, the metal conpound is used in an amount ranging from 1.0×10 -8 to 1.0×10 -4 mole, preferably 5×10 -8 to 5×10 -5 mole per mole of silver halide.
The fogging degree of the direct positive type silver halide emulsion fogged in advance can encompasses a wide range. This fogging degree relates to the kind and concentration of the fogging agent used, pH, pAg, and temperature of an emulsion at the point of providing fogging and the time for fogging as well as the silver halide composition and grain size of the silver halide emulsion used.
Fogging of a grain surface with a fogging agent is generally carried out at a pH of 4.8 or more, and not higher than 11, preferably from 5.0 to 10.0 pAg of 8.0 or less and not less than 5.0, preferably from 5.5 to 8.0 and a temperature of 40° C. or more and not higher than 85° C., preferably from 45° to 80° C. for about 2 to 200 minutes, preferably about 5 to 150 minutes.
After fogging, the bleaching step is performed which entails adjusting the pH to 4.5 or less, preferably not lower than 1.5, more preferably from 4.5 to 2.0 and/or the pAg to 8.1 or higher, preferably not higher than 11, and more preferably from 8.1 to 10.5. When pH is adjusted to 4.5 or less, pAg is preferably within the range of from 5 to 11, and more preferably 8.1 to 11, and when pAg is adjusted to 8.1 or more, pH is preferably within the range of from 1.5 to 11, and more preferably 1.5 to 4.5. By such a treatment, small size-fogged nuclei (Ag nuclei) on the grain surface which do not contribute to Dmax and to increase development proceeding properties are preferentially oxidized (bleached), whereby a high Dmax, a high sensitivity and a high contrast can be simultaneously achieved. Further, the oxidation of such useless Ag nuclei can lower Dmin. The amount of time for the bleaching step is preferably from about 1 to 120 minutes, more preferably from about 2 to 100 minutes, and the temperature during the bleaching step is preferably from 25° to 80° C., more preferably from 30° to 75° C. Prolongation of the time and elevation of the temperature can promote bleaching and these can be optimized so that the desired performances can be obtained.
In order to adjust the pH to 4.5 or lower acids such as acetic acid, hydrochloric acid, phosphoric acids, citric acid, sulfuric acid, malic acid, and salicylic acid may be used. Also, the pAg can be increased with halides such as bromide, chloride, and iodide (e.g., KBr, NaCl, KI), and organic compounds such as mercaptotetrazoles, mercaptotriazoles, benzothiazole-2-thiones, benzotriazoles, benzimidazoles, hydroxytetrazaindenes, and purines which are capable of combining with an Ag ion. Halides are preferred.
In order to stabilize the Ag nuclei it is necessary to raise the pH of the emulsion to a value within the range of 5.0 to 8.0, more preferably 5.3 to 7.8 and/or lower the pAg to a value within the range of 7.8 to 5.5, more preferably 7.4 to 5.8, at a temperature preferably of from 70° to 20° C., more preferably 60° to 25° C. to completion of the bleaching step.
Alkalis such as sodium hydroxide and potassium hydroxide can be used to adjust the pH and silver nitrate can be used to adjust the pAg.
Adjusting the pH and the pAg produces a stability compatible with the photographic characteristics such as a high sensitivity, high Dmax, low Dmin, and a high contrast.
For further stabilizing the Ag nuclei, a reducing agent such as formamidinesulfinic acid, hydrazine, a polyamine (e.g., triethylenetetramine and tetraethylenepentamine), formalin, phosphonium chloride, an amine borane compound, a boron hydride compound, stannous chloride, and tin chloride is preferably added, at an emulsion temperature of 50° C. or lower, preferably 40° C. or lower (preferably not lower than 20° C. in order to maintain the emulsion at a state capable of being stirred), in an amount of 10 -8 to 10 -2 mole/mole Ag, preferably 10 -6 to 10 -3 mole/mole Ag, and preferably at a pH of from 5.3 to 7.5 and at a pAg of from 5.8 to 7.4. Consitions (i.e., the type of the reducing agent, the pH, the pAg and the temperature of the emulsion) are selected or controlled so that fogging does not proceed in the emulsion.
The silver halide emulsion used in the present invention may be manufactured by any of an acid method, a neutral method and an ammonia method and the silver halide can iclude silver bromide, silver chloride, silver bromochloride, silver bromoiodide, and silver bromochloroiodide.
The silver halide grains advantageously have an average grain diameter of 0.01 to 2μ, preferably 0.02 to 1μ. The grain size frequency distribution may be either broad or narrow and is preferably narrow. In particular, a monodispersed emulsion in which 90%, preferably 95%, of the whole grain number falls within the grain size range of ±40%, preferably ±20%, of an average grain size is preferred. The silver halide grains either have a single crystal habit or a mixture of various crystal habits. The single crystal habit is preferred.
The direct positive type silver halide used in the present invention can contain inorganic desensitizers (that is, noble metal atoms contained in the silver halide grains) compounds and the organic desensitizers adsorbing on the surface of a silver halide grain singly or in combination thereof.
The inorganic desensitizers may be incorporated into the silver halide grains in the form of an aqueous solution of the water-soluble noble metal compound before, during or after formation of the grains. For example, chlorides of Group VIII metals in the periodic table, such as iridium and rhodium, in an amount of 10 -7 to 10 -2 mole, preferably 10 -5 to 10 -3 mole per mole of silver halide can be used in preparing the silver halide grains.
Other various photographic additives generally used can be incorporated into the direct positive silver halide photographic light-sensitive material of the present invention. These additives may include stabilizers, for example, triazoles, azaindenes, quaternary benzothiazolium compounds, mercapto compounds, and water soluble inorganic salts of cadmium, cobalt, nickel, manganese, gold, thallium, and zinc. Further, a hardener can be included, for example, aldehydes such as formalin, glyoxale and mucochromic acid, S-triazines, epoxides, aziridines, and vinyl sulfonic acid, as a coating aid, for example, saponin, sodium polyalkylenesulfonate, lauryl or oleyl monoether of polyethylene glycol, amylized alkyltaurine, and fluorine-containing compounds. Also, sensitizers can be included, for example, polyalkylene oxide and derivatives thereof. In addition, color couplers, whitening agents, UV absorbers, anti-septic agents, matting agents, and anti-electrification agents can be used according to necessity.
In the present invention, a dye can be used to prevent the generation of irradiation and fog under a safelight. The dye can have a main absorption in a visible wavelength region among a specific light-sensitive wavelength region of a silver halide emulsion. Among these dyes, those having a λmax falling within the range of 350 to 600 nm are preferred. The chemical structure of the dye is not specifically limited and example of the dye include oxonol dyes, hemioxonol dyes, merocyanine dyes, cyanine dyes, and azo dyes. A water soluble dye is useful for preventing a residual color after processing.
Further examples of the dye include, the pyrazolone dyes described in JP-B-58-12576, the pyrazolone oxonol dyes described in U.S. Pat. No. 2,274,782, the diaryl azo dyes described in U.S. Pat. No. 2,956,879, the styryl dyes and butadienyl dyes described in U.S. Pat. Nos. 3,423,207 and 3,384,487 the merocyanine dyes described in U.S. Pat. No. 2,527,583, the merocyanine dyes and oxonol dyes described in U.S. Pat. Nos. 3,486,897, 3,652,284 and 3,718,472, enaminohemioxonol dyes described in U.S. Pat. No. 3,976,661, and the dyes described in British Patents 584,609 and 1,177,429, JP-A-48-85130, JP-A-49-99620, and JP-A-49-114420, and U.S. Pat. Nos. 2,533,472, 3,148,187, 3,177,078, 3,247,127, 3,540,887, 3,575,704, and 3,653,905.
In the present invention, a cyanine dye is preferably used as a desensitizing dye. The preferred cyanine dye used can be represented by the following formulae (I) to (III).
First, the dyes represented by Formulae (I) to (III) will be explained. ##STR1##
In Formulae (I) to (III), R 1 and R 3 each preferably has from 1 to 12 carbon atoms (including carbon atoms in substituents) each represent an alkyl group, for example, an unsubstituted alkyl group including, for example, methyl, ethyl, propyl, isopropyl, n-butyl, n-pentyl, and n-hexyl; a hydroxyalkyl group including, for example, β-hydroxyethyl and γ-hydroxypropyl; an acetoxyalkyl group including, for example, β-acetoxyethyl and γ-acetoxypropyl; an alkoxyalkyl group including, for example, β-methoxyethyl and γmethoxypropyl; a carboxyalkyl group including, for example, β-carboxyethyl, γ-carboxypropyl, δ-carboxybutyl, and ω-carboxypentyl; an alkoxy-carbonylalkyl group including, for example, β-methoxy-carbonylethyl and γ-ethoxycarbonylpropyl; a sulfoalkyl group including for example, β-sulfoethyl, γ-sulfopropyl, γ-sulfobutyl, and δ-sulfobutyl; an aralkyl group including, for example, benzyl and phenethyl; a sulfoaralkyl group including, for example, p-sulfophenethyl; a carboxyaralkyl group including, for example, p-carboxyphenethyl; and a vinylmethyl group.
R 2 represents a hydrogen atom or a substituent useful for a pyrazolo [5,1-b]quinazolone compound, including, for example, an alkyl group, for example, methyl, ethyl, propyl and benzyl; an alkoxyl group, for example, methoxyl and ethoxyl; a carboxyl group, an alkoxycarbonyl group, for example, methoxycarbonyl and ethoxycarbonyl; a hydroxyl group; and an aryl group, for example, phenyl and p-methoxyphenyl.
R 4 represents a hydrogen atom, an alkyl group including, for example, methyl, ethyl and propyl; a cycloalkyl group including, for example, cyclohexyl; or an aryl including as, for example, phenyl.
L 1 and L 2 each represent a methine group including, for example, --CH═ and --CR 6 ═ (Wherein R 6 represents an alkyl group including, for example, methyl, ethyl and ethoxyethyl; an aryl group including, for example, phenyl).
L 1 and R 1 may be combined via a methylene chain.
Z represents a group Of atoms necessary to form an cyanine heterocyclic nucleus. Examples of a nucleus include, an oxazoline nucleus, an oxazole nucleus, an benzoxazole nucleus, an naphthoxazole, a thiazoline nucleus, a thiazole nucleus, a benzothiazole nucleus, a naphthothiazole, a benzoselenazole nucleus, a naphthoselenazole nucleus, a pyridine nucleus, a quinoline nucleus, an isoquinoline nucleus, an imidazole nucleus, a benzimidazole nucleus, a naphthoimidazole nucleus, an indolenine nucleus, a quinoxaline nucleus, a naphthyridine nucleus, and a pyrroline nucleus.
R 5 represents a substituent useful for a pyrazolo [5,1-b]quinazolone compound, including, for example, a halogen atom (for example, a fluorine atom, a chlorine atom and a bromine atom), a lower alkyl group having from 1 to 4 carbon atoms (for example, methyl and ethyl), an alkoxyl group (for example, methoxyl and ethoxyl), an aryl group (for example, phenyl), a carboxyl group, an alkoxycarbonyl group (for example, methoxycarbonyl), an acylamino group (for example, acetylamino group), an amino group, a nitro group, a phenoxy group, an alkylamino group, and a sulfonic acid group.
n represents 0 or 1, m represents 0, 1, or 2, and p represents 1, 2, 3 or 4.
X⊖ represents an acid anion including, for example, a chlorine ion, a bromine ion, an iodine ion, a thiocyanic acid ion, perchloric acid ion, a p-toluenesulfonic acid ion, a methylsulfuric acid ion, and an ethylsulfuric acid ion.
A particularly preferred dye is a dye represented by Formula (II) or (III), in which R 2 represents an alkyl group or an aryl group and, in Formula III, in which R 4 represents an alkyl group.
Examples of compounds represented by Formulae (I) to (III) are shown below but not limited thereto. ##STR2##
The dyes described above are incorporated into a silver halide emulsion layer and the addition amount is in the range of 50 mg to 2 g per mole of silver halide.
Excellent results can be obtained according the objects of the present invention by incorporation of or by processing the photographic material in the presence of a compound in which a sulfur atom forms a bond with a silver ion to adsorb on the surface of a silver halide crystal, such as mercaptotetrazoles, mercaptotriazoles, mercaptothiadiazoles, and benzothiazole-2-thiones, and a compound in which a nitrogen atom forms a bond with a silver ion to adsorb on the surface of a silver halide crystal, such as benzotriazoles, benzimidazoles, hydroxytetrazaindenes, and purines.
Of the above-described sulfur-containing compounds, a preferred compound is a compound having a mercapto group and especially that represented by the following Formula (IV):
Z-SM (IV)
wherein Z represents an aliphatic group (for example, a substituted alkyl group such as carboxyethyl, hydroxyethyl, and diethylaminoethyl), an aromatic group (for example, phenyl) or a heterocyclic group (preferably a 5- or 6-membered ring having at least one of N, O, S and Se atoms as hetero-atom).
The total carbon number of the aliphatic group and aromatic group is preferably 18 or less. M represents a hydrogen atom, an alkali metal atom such as Na and K, or NH 4 .
Among these compounds, particularly preferred is a heterocyclic residue containing one or more nitrogen atoms in the molecule The total carbon atom number is preferably 30 or less, more preferably 18 or less.
The heterocyclic residue represented by Z may be further condensed. Preferred examples of the residue include residues of imidazole, triazole, tetrazole, thiazole, oxazole, selenazole, benzimidazole, benzoxazole, benzothiazole, thiadiazole, oxadiazole, benzoselenazole, pyrazole, pyrimidine, triazine, pyridine, naphthothiazole, naphthoimidazole, naphthoxazole, azabenzimidazole, purine, and azaindene (for example, triazaindene, tetrazaindene and pentazaindene).
Further, the aliphatic gorup, aryl gorup, heterocyclic residues and condensed rings may be substituted with suitable substituents.
For example, the substituent can include an alkyl group (for example, methyl, ethyl, hydroxyethyl, trifluoromethyl, sulfopropyl, dipropylaminoethyl, and adamantane), an alkenyl group (for example, allyl), an aralkyl group (for example, benzyl and p-chlorophenethyl), an aryl group (for example, phenyl, naphthyl, p-carboxyphenyl, 3,5-dicarboxyphenyl, m-sulfophenyl, p-acetamidophenyl, 3-capramidophenyl, p-sulfamoylphenyl, m-hydroxyphenyl, p-nitrophenyl, 3,5-dichlorophenyl, and 2-methoxyphenyl), a heterocyclic residue (preferably 5- or 6-membered heterocyclic residue having at least one of N, O, S and Se atoms as hetero-atom, for example, pyridine), a halogen atom (for example, a chlorine atom and a bromine atom), a mercapto group, a cyano group, a carboxyl group, a sulfo group, a hydroxy group, a carbamoyl group, a sulfamoyl group, an amino group, a nitro group, an alkoxy group (for example, methoxy and ethoxy), an aryloxy group (for example, phenoxy), an acyl group (for example, acetyl), an acylamino group (for example, acetylamino, capramide, and methylsulfonylamino), a substituted amino group (for example, diethylamino and hydroxyamino), an alkyl- or arylthio group (for example, methylthio, carboxyethylthio, and sulfobutylthio), an alkoxycarbonyl group (for example, methoxycarbonyl), and an aryloxycarbonyl group (for example, phenoxycarbonyl). As shown above as examples, these substituents may be further substituted with, for example, a hydroxyl group, a methoxy group, a halogen atom, a sulfo group or a caroxyl group.
Further, a disulfide compound (Z-S-S-Z; wherein Z has the same meaning as that in Formula (IV)) may be used which decomposes to form a compound represented by Formula (IV).
The sulfur-containing compounds can include a compound having a thioketone group as represented by the Formula (V): ##STR3## wherein R represents an alkyl group, an aralkyl group, an alkenyl group, an aryl group or a heterocyclic group; X represents a group of atoms necessary to form a 5- or 6-membered ring and may be condensed.
The heterocyclic ring formed by X is preferably 5- or 6-membered heterocyclic residue having at least one of N, O, S and Se atoms as hetero-atom, for example, thiazoline, thiazolidine, selenazoline, oxazoline, oxazolidine, imidazoline, imidazolidine, thiadiazoline, oxadiazoline, triazoline, tetrazoline, or pyrimidine as well as a heterocyclic ring condensed with a hydrocarbon ring or a heterocyclic ring, such as, benzothiazoline, naphthothiazoline, tetrahydrobenzothiazoline, benzimidazoline, and benzoxazoline.
Groups represented by R and X each may be substituted with the substituents described for the compound represented by Formula (IV) and they preferably have total carbon atoms of from 1 to 12.
Groups representative of R can include, as the alkyl group, for example, methyl, propyl, sulfopropyl, and hydroxyethyl; as the alkenyl group, for example, allyl; as the aralkyl group, for example, benzyl; as the aryl group, for example, phenyl, p-tolyl, and o-chlorophenyl; and as the heterocyclic group (which is preferably 5- or 6-membered heterocyclic residue having at least one of N, O, S and Se atoms as hetero-atom, for example, pyridyl.
Next, representative, but non-limiting, examples of the compound represented by Formula (IV) are shown below. ##STR4##
Next, representative, but non-limiting examples of the compounds represented by Formula (V) are shown below: ##STR5##
These compounds represented by Formulae (IV) or (V) can be obtained as described in Stabilization of Photographic Silver Halide Emulsions, E. J. Birr, Focal Press Co., 1974; Rer. Prog. Appl. Chem.; C. G. Barlow et al, Vol. 59, p. 159 (1974), Research Disclosure, 17643 (1978), JP-B-48-34169, JP-B-47-18008, and JP-B-49-23368, and Beilsteln XII, 394, IV, No. 121.
These sulfur compounds are added to a silver halide emulsion layer and the addition amount is preferably 0.1 to 100 mg/m 2 , particularly 0.5 to 50 mg/m 2 , above all 1.0 to 20 mg/m 2 .
The developing agent used for the development processing of the silver halide photographic light-sensitive material according to the present invention can include, for example, the organic or inorganic developing agents and developing aids described in The Theory of the Photographic Process, E. K. Meath & T. H. James, Vol. 3, pp. 278-381 (1966), and can be used singly or in combination thereof. Preferred developing agents include ferrous oxalate; hydroxylamine; N-hydroxymorpholine; hydroquinones such as hydroquinone, hydroquinone mono-sulfonate, chlorohydroquinone, and t-butylhydroquinone; catechol; resorcine; pyrrogalole; amidol; phenidone, pyrazolidones such as 4-hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone; paraminophenols such as paraminophenol, glycine and methole; paraphenylenediamines such as paraphenylenediamine and 4-amino-N-ethyl-N-ethoxy-aniline, and ascorbic acid. More preferred examples are methole singly, the combination of phenidone and methole, the combination of methole and hydroquinone, the combination of phenidone, methole and t-butylhydroquinone, the combination of phenidone and ascorbic acid, and the combination of phenidone and aminophenol. However, the use of other combinations can provide almost the same good results and the present invention is not limited to the preferred examples.
The above-described developing agent, which can be incorporated into the developing solution used for the silver halide photographic light-sensitive material of the present invention, may be used generally in an amount of 1×10 -5 to 1 mole/liter of the developing solution. In particular, hydroquinone is used preferably in the amount of 20 g/liter or more, more preferably 25 g/liter or more.
In addition to the above-described developing agent, a preservative such as sulfite and hydroxylamine can be added to the developing solution. Also, compounds having the functions of pH controll and buffering used for a general black-and-white developing solution, such as caustic alkali, alkali carbonate, alkali borate, and amines, an inorganic development inhibitor such as potassium bromide, and an organic development inhibitor such as benzimidazole, benzotriazole, and nitroindazole, as described in British Patent 1,376,600, can be added to the developing solution.
The direct positive silver halide photographic light-sensitive material according to the present invention has various applications. For example, it can be used for various photographic light-sensitive materials for printing such as duplicating, reproduction and offset master, a specific photographic light-sensitive material for an X-ray photograph, a flash photograph and an electron beam photograph, and various direct positive photographic light-sensitive materials for general duplication, micro duplication, a direct positive color material, a quick stabilized material, a diffusion transfer material, a color diffusion transfer material, and a single bath developing-fixing. The direct positive silver halide photographic light-sensitive materials of the present invention have a high contrast and a very high stability under a storage over a long period of time and a high temperature and humidity.
The present invention will be explained below with reference to examples but the embodiments of the present invention are not limited thereto.
EXAMPLE 1
Citric acid was added to a gelatin aqueous solution maintained at 50° C., and an AgNO 3 aqueous solution and a halide aqueous solution were added thereto by a controlled double jet method under the presence of thioether (HOCH 2 CH 2 SCH 2 CH 2 SCH 2 CH 2 OH) over a period of 60 minutes, whereby a cubic monodispersed silver bromide emulsion having an average grain size of 0.24 μm was prepared.
This emulsion was desalted by a flocculation method and then gelatin was added thereto. After maintaining the temperature and pH at 65° C. and 6.0, respectively, formamidinesulfinic acid, in an amount of 0.008 millimole per mole of silver, was added and then chloroauric acid, in an amount of 0.0008 millimole per mole of silver, was added, followed by ripening for 60 minutes. After sampling emulsion a (emulsion a had a pAg of 7.2 and a pH of 6.2, respectively), KBr and phosphoric acid were added to settle the pAg and pH to 9.0 and 4.4, respectively, and the emulsion was ripened for 30 minutes at a temperature of 45° C. under the condition of bleaching a silver nucleus, followed by adding AgNO 3 and NaOH and setting the pAg and pH to 7.2 and 6.2, respectively. This emulsion was designated as emulsion b and stored at a temperature of 12° to 2° C.
Compound I-22 which was given as an example of a compound of Formulas (I) to (III) was added as a desensitizing dye as shown in Table 1 and the solution was coated on a polyethylene terephthalate film so that the coated amount of Ag became 2.7 g/m 2 . A protective layer containing gelatin on amount of 1.2 g/m 2 , 40 mg of amorphous SiO having an average grain size of 3μ as a matting agent, methanol silica in an amount of 0.1 g/m 2 , a fluorinated surface active agent (Compound F shown below) and sodium dodecylbenzenesulfonate as a coating aid, and a KBr aqueous solution for adjusting pAg in a layer were simultaneously coated thereon. These light-sensitive materials are designated as A and B. ##STR6##
Light-sensitive materials A and B were subjected to sensitometry exposure via a step wedge of ΔD=0.1 and then to development processing with an automatic developing machine FG 660F manufactured by Fuji Photo Film Co., Ltd. in the following developing solution A and a fixing solution (GR-Fl manufactured by Fuji Photo Film Co., Ltd.) at the developing conditions of 34° C. and 30 seconds.
After processing, Dmin (miminum density), Dmax (maximum density), S 1 .5 (sensitivity at the density of 1.5), and the average gradation (G) 0130 were measured. The results thereof are shown in Table 1.
The average gradation (G) 0130 is represented by the ratio of the density difference (ΔD=2.9) to the difference (Δlog E) between the sensitivity in the density of 0.1 and the sensitivity in the density of 3.0.
It can be seen from the results shown in Table 1 that the emulsion prepared according to the method of the present invention provides a high sensitivity and a high gradation, in contrast to the comparative emulsion, while giving the same Dmax and a low Dmin.
TABLE 1______________________________________Sample Emul- Dye Addition D- D-No. sion No. amount max min S.sub.1.5 G.sub.0130______________________________________A a I-22 16 mg/m.sup.2 5.3 0.05 100 6.5(Comp.)B b I-22 16 mg/m.sup.2 5.3 0.03 125 8.2(Inv.)______________________________________Developing solution A______________________________________Hydroquinone 50.0 gN-methyl-p-aminophenol 0.3 gSodium hydroxide 18.0 g5-Sulfosalicylic acid 30.0 gBoric acid 25.0 gPotassium sulfite 110.0 gSodium ethylenediaminetetracetate 1.0 gPotassium bromide 10.0 g5-Methylbenzotriazole 0.4 g2-Mercaptobenzimidazole-5-sulfonic acid 0.3 gSodium 3-(5-mercaptotetrazole) 0.2 gbenzenesulfonateN-n-butyldiethanolamine 15.0 gSodium toluenesulfonate 8.0 gWater was added to 1 literpH was adjusted to 11.6(by adding potassium hydroxide)______________________________________
EXAMPLE 2
The same samples as light-sensitive material B prepared in Example 1 were prepared as shown in Table 2 and evaluated in the same manner as in Example 1, except that the pAg and pH were changed in accordance with the amounts of KBr and phosphoric acid in preparing emulsion be in order to prepare emulsions in which only the silver bleaching condition was changed.
As Shown by the results set forth in Table 2, a high sensitivity, a high contrast and low Dmin can be achieved while maintaining high Dmax (in a practical use, it is sufficient that Dmax 5.0 or more).
TABLE 2______________________________________SampleNo. Emulsion pAg pH Dmax Dmin S.sub.1.5 G.sub.0130______________________________________C (Inv.) c 7.2 4.4 5.3 0.04 102 6.6D (Inv.) d 7.8 4.4 5.3 0.04 104 6.7E (Inv.) e 8.0 4.4 5.3 0.04 105 7.0F (Inv.) f 8.5 4.4 5.3 0.04 110 7.5G (Inv.) g 8.8 4.4 5.3 0.03 124 8.0H (Inv.) h 9.5 4.4 5.2 0.03 130 8.1I (Inv.) i 10.0 4.4 5.1 0.03 135 7.9J (Inv.) j 8.0 4.2 5.3 0.04 108 7.0K (Inv.) k 8.5 4.2 5.3 0.04 113 7.5L (Inv.) l 9.0 4.2 5.2 0.03 128 8.2M (Inv.) m 10.0 4.2 5.1 0.03 136 7.9N (Inv.) n 8.5 3.8 5.3 0.03 115 7.5O (Inv.) o 8.5 3.5 5.2 0.03 118 7.5P (Inv.) p 8.5 3.0 5.1 0.03 122 7.5Q (Inv.) q 8.5 2.0 5.0 0.03 128 7.5R (Inv.) r 8.5 4.6 5.3 0.04 103 7.0S (Comp.) s 7.8 4.6 5.3 0.04 100 6.5______________________________________
EXAMPLE 3
Emulsion a' was prepared in the same manner as in Example 1 except that KBr and phosphoric acid were not added, the silver bleaching step was not carried out and the pAg and pH were set at 7.2 and 6.2, respectively. Formamidinesulfinic acid in an amount per mole of Ag as shown in Table 3 was added to emulsions a' and b at 40° C. before storage. The emulsions were solidified in a refrigerator (8° C.) and then were used on the first day and 60th day to prepare the samples in the same manner as in Example 2. The samples were processed and evaluated in the same manner as in Example 2 to check the change in sensitivity.
The results shown in Table 3 illustrate that the addition of formamidinesulfinic acid can improve the storage stability of the emulsions in a refrigerator without affecting sensitivity to a large extent.
TABLE 3______________________________________ Formamidine- sulfinic acid* S.sub.1.5Sample No. Emulsion (mol/Ag mol) 1st day 60th day______________________________________A'-1 (Comp.) a' 0 100 150A'-2 (Inv.) a' 0.008 mmol 100 104A'-3 (Inv.) a' 0.04 mmol 100 103A'-4 (Inv.) a' 0.08 mmol 101 102A'-5 (Inv.) a' 0.8 mmol 102 103B-1 (Inv.) b 0.008 mmol 125 130B-2 (Inv.) b 0.04 mmol 125 130B-3 (Inv.) b 0.08 mmol 126 130B-4 (Inv.) b 0.8 mmol 127 131______________________________________
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | There is disclosed a method for preparing a direct reversal type silver halide light-sensitive emulsion which is used for a black-and-white light-sensitive material and has the improved photographic performances of a high sensitivity and a high contrast. The method comprises:
A method for preparing a fogging type direct positive silver halide emulsion comprising the steps of:
(a) forming an emulsion containing silver halide grains;
(b) fogging surfaces of the grains with a reducing agent to form a silver nuclei; and then
(c) performing at least one of an adjustment of pH of the emulsion to 4.5 or less and an adjustment of pAg of the emulsion to 8.1 or more. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to electric irons and, more particularly, to controlling delivery of water to a steam generator in an electric iron.
Modern electric irons are distinguished by apparatus for producing a supply of steam contacting a fabric material being smoothed. The iron includes a heated sole plate and an internal water reservoir. Water from the water reservoir is metered at a predetermined flow rate into contact with an internal heated surface of the sole plate. The water turns to steam upon contact with the sole plate. The steam flows through apertures in the sole plate into contact with the fabric.
Metering of water from the reservoir to the sole plate is conventionally controlled by a metering rod providing a predetermined annular space between itself and a metering aperture. A seal surrounding the metering rod is lowered into a sealing condition about the perimeter of the metering aperture by a suitable cam arrangement.
The prior art steam-control apparatus described above produces a single water-delivery rate and is thus limited to the generation of steam at a corresponding single rate. The ability to vary the rate of steam generation may be desirable for accommodating different fabric weights and types. The above prior-art devices are incapable of providing such variable steam generation.
Modern appliances rely on the design of the device for aiding the assembly process. In an electric iron requiring cam actuation of an actuating rod, a problem exists in providing drop-in assembly of the cam onto the actuating rod. This problem is compounded in an appliance having an actuating cam with a plurality of land levels for controlling a plurality of water metering rates to the sole plate of an electric iron.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the invention to provide an electric iron having a selectable plurality of water flow rates for steam generation.
It is a further object of the invention to provide an electric iron having a water metering valve including a metering rod having at least two diameters and a metering aperture operative, together with the metering rod, for controlling a flow of water to a sole plate of the electric iron. A cam positions the metering rod at one of a plurality of axial positions for controlling the rate of water delivery to the sole plate and the consequent rate of steam generation.
It is a further object of the invention to provide a cam for actuating an actuating rod wherein the cam includes an assembly position permitting drop-in assembly thereof and at least two user positions. The cam is actuable a single time from the manufacturing to one of the user positions and is thereafter incapable of returning to the assembly position.
Briefly stated, the present invention provides a variable steam control for a steam iron employing a metering rod having a plurality of cylindrical portions of successively decreasing diameters. A cam controls the position of the metering rod to position a selectable one of the cylindrical portions within a circular opening, whereby controllable water flow rates, and consequent steam flow rates are attained. The cam includes an assembly region having a cam-installation opening therein, usable following drop-in assembly, for enabling a head of a steam-control actuator rod to pass through the cam. A one-time movement of the cam locks the head in one of a plurality of user regions and blocks return to the assembly region.
According to an embodiment of the invention, there is provided a variable steam control for an electric iron, the electric iron including a water reservoir and a heatable steam chamber, comprising: a tap-water valve communicable with water in the water reservoir, a metering rod passing through an opening in the tap-water valve, a water channel from the tap-water valve to the steam chamber, the metering rod including at least first and second portions having first and second different cross-sectional dimensions, respectively, the opening having a third cross-sectional dimension, the third cross-sectional dimension being larger than the first and the second cross-sectional dimensions, and means for selectively positioning one of the at least first and second portions in the opening whereby at least first and second different water flow rates into the steam chamber are provided.
According to a feature of the invention, there is provided apparatus for permitting assembly of a metering rod to a cam comprising: an assembly region and at least two user regions on the cam, an opening in the assembly region through the cam, a head on the metering rod, the opening being sized to permit passage of the head therethrough, a ramp in the assembly region leading to the at least two user regions, means for permitting the cam to move relative to the head whereby one of the at least two user regions contains the head, and means for blocking the head from returning to the assembly region.
According to a further feature of the invention, there is provided a method for assembly a metering rod to a cam, the cam having an assembly region and at least two user regions, comprising: passing the head through an opening in the assembly region, sliding the head up a ramp in the assembly region leading to the at least two user regions, and blocking the head from returning to the assembly region.
The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of an electric iron according to an embodiment of the invention partly cut away to reveal a steam-control valve.
FIG. 2 is a cross section of the steam-control valve of FIG. 1.
FIG. 3 is a cross section of a steam-control cam knob and cylindrical cam of the embodiment of the invention in FIG. 2.
FIG. 4 is a cross section taken along IV--IV in FIG. 3.
FIG. 5 is a developed view of the cylindrical cam of FIG. 4 taken in the direction V--V.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to FIG. 1, there is shown, generally at 10, an electric iron according to an embodiment of the invention. A housing 12 is affixed to a sole plate 14 by any convenient means (not shown). Housing 12 is conventionally of polypropylene or other plastic unable to withstand, without melting, the temperatures at which sole plate 14 is operated. A heat barrier 16 of a heat-resistant material such as, for example, a phenolic plastic, is interposed between sole plate 14 and housing 12. Electric power is fed to a heating element (not shown) in thermal contact with sole plate 14 through a flexible electric cord 18.
Electric iron 10 includes several controls (some of which are not shown) including a temperature control 20, a water spray pump button 22 and a steam-control cam knob 24. A water reservoir 26 is disposed within housing 12. A steam-control actuator rod 28, interacting with steam-control cam knob 24 in a manner to be described hereinafter, enters water reservoir 26 from above. A steam-control valve 30 is aligned with steam-control actuator rod 28 between water reservoir 26 and sole plate 14.
The present invention is principally concerned with steam-control cam knob 24, water reservoir 26 and steam-control valve 30. The remaining elements in electric iron 10, although defining the environment within which the items of interest are contained, are assumed to be conventional and their description would not add to the present teaching. Thus, description of such assumed conventional elements is omitted.
Referring now to FIG. 2, steam-control valve 30 includes a tap-water valve 32 having a dome-shaped seal 34 with a circular opening 36 centered in its upper surface. A metering rod 38, axially affixed to a lower end of steam-control actuator rod 28, passes through circular opening 36. An inverted conical sealing surface 40 sealingly engages an upper surface of dome-shaped seal 34 when steam-control valve 30 is in the sealing position illustrated in the figure.
Metering rod 38 includes a plurality such as, for example, four cylindrical portions 42, 44, 46 and 48 having successively smaller diameter axially aligned therewith. A scraper plate 50 is optionally contained within an interior 52 of tap-water valve 32 for removing scale, or other contaminants, from cylindrical portion 48. Openings 54, of relatively large size, permit substantially free communication of water between upper and lower surfaces of scraper plate 50. A water channel 56 leads to a steam chamber 58 within sole plate 14 from whence steam generated by water passing through steam-control valve 30 and contacting a heated surface in sole plate 14 is distributed through openings (not shown) to a fabric (not shown) being smoothed.
Steam-control valve 30 is actuated by raising steam-control actuator rod 28 a predetermined distance to position a selected one of cylindrical portions 42-48, aligned within circular opening 36. Each diameter of cylindrical portions 42-48 creates an annular gap between itself and circular opening 36 having an area equal to the difference between its cross-sectional area and the area of circular opening 36. Although different applications may require different dimensions, in one embodiment, circular opening 36 has a diameter of 0.038 inch and cylindrical portions 42-48 have diameters of 0.035, 0.034, 0.30, and 0.28 inch, respectively.
Referring now to FIG. 3, steam-control cam knob 24 includes an aperture 60 into which water spray pump button 22 is fitted. Water spray pump button 22 is not of concern to the present invention and its location is indicated in dashed lines. In addition, a volume 62 is provided for containing a water spray pump (not shown) actuated by water spray pump button 22, but the apparatus fitting into volume 62 is omitted to reduce clutter in the drawing.
Steam-control cam knob 24 includes an annular groove 64 in its underside. A cylindrical cam 66 includes an annular flange 68 extending from its upper edge into engagement with annular groove 64. Annular groove 64 and annular flange 68 are preferably bonded or welded together during preassembly of housing 12 to capture a flange 70 of housing 12 between them.
A guide 72 guides vertical displacement of steam-control actuator rod 28 as indicated by a double-headed arrow 74. An annular groove 76 engages a lower end of a resilient member such as, for example, a coil spring 78. An upper end of coil spring 78 bears against a washer 80 in contact with a lower surface of guide 72. A small-diameter portion 82 of steam-control actuator rod 28 passes through a part-annular slot 84 in cylindrical cam 66. An enlarged head 86 crowns an upper end of steam control actuator rod 28.
Referring now also to FIG. 4, cylindrical cam 66 includes a cam portion 88 subtending substantially more than 180 degrees and a solid portion 90 subtending the remainder of the circumference of cylindrical cam 66. Cam portion 88 is enclosed between an outer wall 92 and an inner wall 94. Part-annular slot 84, radially centered in cam portion 88, includes a cam-installation opening 96 at one end thereof.
Referring now also to FIG. 5 (together with FIGS. 3 and 4), representing cylindrical cam 66 developed, or flattened out, cam portion 88 includes five discrete angular regions, represented as lengths in the developed view. An assembly region 98 includes a land 100, generally coextensive with cam-installation opening 96, and a ramp 102. The upper extremity of ramp 102 is halted at a blocking wall 104 which falls off substantially vertically to a land 106 of an OFF region 108. A ramp 110 of OFF region 108 leads upward to join a land 112 of a LOW region 114. A ramp 116 of land 112 leads upward to join a land 118 of a MED region 120. Finally, a ramp 122 of MED region 120 leads upward to join a land 124 of a HIGH region 126. A vertical wall 128 blocks the extremity of HIGH region 126.
In FIG. 3, manufacturing assembly is conveniently arranged to prepare steam-control cam knob 24 and cylindrical cam 66 in one subassembly and the elements including enlarged head 86, small-diameter portion 82 and below in a second subassembly. The embodiment of the invention illustrated permits drop-in assembly of these elements without separate final assembly of cylindrical cam 66 to enlarged head 86 and steam-control actuator rod 28. Specifically, the upper elements are positioned over the lower elements with steam-control cam knob 24 turned to align cam-installation opening 96 over enlarged head 86. The upper elements are then dropped into position with enlarged head 86 moving to the position shown in FIG. 5. Downward travel of enlarged head 86 is limited by the seat between inverted conical sealing surface 40 and dome-shaped seal 34 (FIG. 2), and thus enlarged head 86 extends slightly above land 100. Assembly is completed by rotating steam-control cam knob 24, with cylindrical cam 66 affixed thereto, until enlarged head 86 rides up ramp 102 against the opposed urging of coil spring 78 (FIG. 3) until enlarged head 86 drops over blocking wall 104 into the vicinity of, or in light contact with, land 106. In this position, steam-control valve 30 remains closed. As cylindrical cam 66 is rotated to positions wherein enlarged head 86 contacts lands of regions 114, 120 and 126, steam-control actuator rod 28 (FIG. 2) is raised to successively position cylindrical portions 44, 46 and 48, respectively, within circular opening 36. Thus, the successive positions of steam-control cam knob 24 and cylindrical cam 66 create successively greater clearances between circular opening 36 and metering rod 38. As a result, successively greater water flow rates are metered through steam-control valve 30 into steam chamber 58 and correspondingly greater steam flow rates are delivered to a fabric being smoothed.
It will be noted that, except for land 100, each land has a slight downward slope toward its ramp (FIG. 5). This provides a stable position for enlarged head 86 at each of the user positions.
Once cylindrical cam 66 is turned from assembly region 98 to the user positions, blocking wall 104 blocks return of enlarged head 86 to assembly region 98. Thus, assembly region 98 is a single-use position enabling a simple assembly operation which, once cylindrical cam 66 is turned to the user positions, is never again required. Similarly, vertical wall 128 blocks travel of enlarged head 86 beyond HIGH region 126.
Although the embodiment of the invention illustrated and described above employs a rotatable cam, on skilled in the art would recognize that corresponding results in assembly and operation are attainable using a linearly movable cam assembly. Such a linearly movable cam assembly should be considered to be within the scope of the present invention.
Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims. | A variable steam control for a steam iron employs a metering rod having a plurality of cylindrical portions of successively decreasing diameters. A cam controls the position of the metering rod to position a selectable one of the cylindrical portions within a circular opening, whereby controllable water flow rates, and consequent steam flow rates are attained. The cam includes an assembly region having a cam-installation opening therein, usable following drop-in assembly, for enabling a head of a steam-control actuator rod to pass through the cam. A one-time movement of the cam locks the head in one of a plurality of user regions and blocks return to the assembly region. | 8 |
RELATED APPLICATION
[0001] The present application claims the benefit of priority under 35 U.S.C. 119 to Canadian Patent Application Serial No. 2,778,306, filed May 25, 2012, and entitled “Telescopic Liquid Tank”, all of which is commonly owned herewith.
FIELD OF THE INVENTION
[0002] The invention relates to tanks for use in fracking operations, and more particularly large volume, transportable, steel water tanks for such use.
BACKGROUND OF THE INVENTION
[0003] Large volumes of water are required for hydraulic stimulation (referred to as fracture or fracking) of well sites. In order to store large volumes of water, either many traditional horizontal rectangular tanks, or many traditional vertical cylindrical tanks, are needed, often in conjunction with a geomembrane lined open top tank (such tanks are prone to damage and leaks).
[0004] Open top tanks are large volume tanks with a large surface footprint. They are usually circular, which is an inefficient use of space. Using open top tanks requires transferring fluid from the tank to a frack tank farm for use by the fracking equipment. Open top tanks are lined with a geomembrane liner that is fragile and prone to damage and leaks. The liner is not reusable, and is expensive to replace. Specialized pumping equipment is required to use with these tanks It is difficult to safely get all of the fluid in a tank from the tank bottom, resulting in some waste. Open top tanks are expensive to clean and decommission, and can cause a major incident in the case of tank failure, as there is no secondary containment. These tanks are not compartmentalized and in case of a failure, the entire volume of water may be lost. There are also limits on the height of these tanks, resulting in large footprints as the liquid capacity per area of land is low
[0005] Vertical cylindrical 400 bbl tanks are a standard oilfield tank, widely used in Canada. Volume of these tanks is normally 400 bbl, or 60 m 3 . At best, these tanks can be transported in pairs on one truck. The cylindrical tanks require elaborate manifolds and many hoses to properly connect the tanks for fracking use. As the tanks have no built in containment, the tank farm is typically bermed and lined. Matting is required underneath the tanks Matting and manifolds and hoses typically require at least one full additional truck load. The cylindrical tanks also take up a large footprint on an area/volume basis.
[0006] Rectangular tanks are either mobile via an axle, or are skidded, or such tanks are widely used in the U.S. These rectangular tanks may have volumes up to 100 m 3 , although 80 m 3 is more common. These tanks have all the disadvantages of the vertical tanks, and require an even larger surface footprint. In addition, they can only be transported or moved as single tanks, which adds to the transportation and set up cost.
[0007] What the current tanks used in fracking operations lack is a built in secondary containment, and integrated or compatible pumping systems, as well as a tank design that is easily transportable but also high volume.
SUMMARY
[0008] The telescopic frack water tanks according to the invention provide large volume fluid storage, a compact footprint, with minimal transportation and installation cost. The system combines three components, namely a large volume horizontal telescopic tank that is highway transportable; has easily integrated pumping systems; and has built in secondary containment
[0009] The tank according to the invention is used to support the hydraulic stimulation (fracture) of shale gas wells. A pad operation for such frac operations likely includes at least three of these tanks, each having a volume of at least 500 m 3 . A first tank serves as a primary storage/receiving tank, and supplies fluid to a second tank. The second tank is used in place of the traditional fracking tank farm and suction manifold, and the fracking equipment blender and charge pumps are tied directly into the second tank. The third tank is used for flowback storage and transfer, replacing the traditional flowback tank farm.
[0010] Large volume storage is thereby realized via one transportable tank according to the invention. The tank is adjustable in height once delivered to the location, to allow for large volume capability. Setup and installation of the tank is fast, resulting in significant transportation cost savings. The incorporated containment prevents environmental spills, and the included recirculation pump transfers fluid from containment back into the tank, if necessary. The incorporated pumping systems and tank connections further increase functionality, and eliminate the need for additional equipment. Each tank can replace several standard vertical tanks, or standard horizontal tanks.
[0011] A system using the tanks according to the invention is capable of transferring high volumes of water to the fracking equipment, pumping at high pressure off the pad to offsite storage, and receiving and transferring flowback water to the primary pad storage tank. In addition, pumping systems allow for fluid circulation to prevent line freeze problems, as well as circulation through a water heater. Incorporated light masts can eliminate additional surface rentals, such as light towers, and incorporated weirs allow compartment separation and can be used for sand settling, chemical injection, and other functions.
[0012] A tank is provided, including: a tray positioned on a skid; a first tank wall positioned on the tray; a second inner tank wall positioned within the first inner tank wall; wherein the first tank wall is moveable from a first position wherein the second inner tank wall is substantially contained within the first tank wall; and a second position wherein said first tank wall is elevated thereby increasing the height and storage capacity of the tank.
[0013] When the first tank wall is in the second position, a seal is formed between the first tank wall and the second tank wall. The first tank wall is moveable from the first position to the second position by a plurality of hydraulic rams. The tank may include a pump positioned to pump water leaking through the seal to the tray back into the tank, or to another location, such as another tank. The seal may include a gasket between a bottom inside portion of the first tank wall and a top outside portion of the second tank wall. The seal may further include a plurality of inflatable hoses positioned between the second tank wall and the first tank wall.
[0014] A further tank is provided, including: a spill containment tray positioned on a skid; a first tank wall positioned on the tray; a second inner tank wall positioned within the first inner tank wall; wherein the second inner tank wall is moveable from a first position wherein the first outer tank wall substantially contains the second inner tank wall; and a second position wherein the second inner tank wall is elevated thereby increasing the height and storage capacity of the tank.
DESCRIPTION OF THE FIGURES
[0015] FIG. 1 is a side view of a tank according to the invention, in a raised position.
[0016] FIG. 2 is an end view thereof.
[0017] FIG. 3 is an end view thereof, showing the tank in a lowered position.
[0018] FIG. 4 is a top view thereof;
[0019] FIGS. 5A , 5 B, 5 C, and 5 D are cross sectional views of fastening elements and sealing elements of the tanks walls according to the invention.
[0020] FIG. 6 is an end view of an alternative embodiment of the tank according to the invention.
[0021] FIG. 7 is a partial cross sectional view of an alternative embodiment of a sealing element for the tank.
[0022] FIG. 8 is a perspective view of a sealing member used in the sealing embodiment.
[0023] FIG. 9 is a cross sectional end view of an alternative embodiment of the tank according to the invention.
[0024] FIG. 10 is a cross sectional view of an embodiment of a seal therein, detailing C in FIG. 9 .
[0025] FIG. 11 is a detailed view of an embodiment of a foldable platform in the tank, detailing B in FIG. 9 .
[0026] FIG. 12A is a sectional view taken along C-C in FIG. 9 of an embodiment of a drip tray within the tank.
[0027] FIG. 12B is a side cross sectional view thereof, detailing A in FIG. 9 .
[0028] FIG. 13 is a perspective view of an embodiment of a tank according to the invention.
[0029] FIGS. 14 a , 14 b , and 14 c are side cross sectional views of an alternate embodiment of the invention showing the raising of the tank wall.
[0030] FIG. 15 is a top view showing the corner of an embodiment of the tank according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] The tank according to the invention includes horizontal tank 10 , as shown in FIGS. 1 through 4 . Tank 10 is secured to skids 20 , and may be of the maximum (oversize) width, length, and height (when in a lowered position) permitted for travel by road.
[0032] Tank 10 includes closed outer tank 30 and closed inner tank wall 40 . Inner tank wall 40 is sized to fit within outer tank 30 , and can be raised telescopically to increase the overall wall height of tank 10 and thereby the storage capacity of tank 10 . Further inner tank walls may be included in tank 10 in a nesting pattern to provide multiple telescopic interior tanks thereby providing increased height when the tank walls are raised.
[0033] Inner tank wall 40 is raised using a plurality of hydraulic lifts 50 , positioned around the exterior wall 60 of outer tank 30 . In a typical embodiment of the invention, six or more lifts 50 would be present to allow for even lifting of inner tank wall 40 . FIGS. 1 and 2 shows inner tank wall 40 in a raised position.
[0034] As shown in FIGS. 5A through 5D , interior tank wall 40 creates a seal with the adjacent exterior wall 60 when the hydraulic lifts are fully extended, and pressure is forced upon opposite faces of wall 40 and wall 60 . FIGS. 5A through 5D each represent an alternative sealing means. Additional sealing is provided by grease injection and gasket material 55 between inner tank wall 40 and exterior wall 60 . Grease injection nipples 45 may be positioned at regular intervals to allow grease injection.
[0035] As seen in FIG. 5A , projection 100 , at the bottom and outside of interior tank wall 40 , is sized to fit indentation 110 at the top and inside of exterior wall 60 . Gasket material 55 is positioned between projection 100 and indentation 110 .
[0036] An alternative embodiment of sealing means is shown in FIG. 5B , in which mating projection 120 at the bottom outside edge of interior tank wall 40 meets the inner edge of mating projection 130 at the top inside edge of exterior tank wall 60 to form a seal. Gasket material 55 is positioned between projections 120 , 130 .
[0037] FIG. 5C shows another embodiment of sealing means, wherein dividers 140 at the bottom of inner tank wall 40 form channels 150 . Inflatable rubber hoses 160 run through each channel 150 , and are inflated when the inner tank wall 40 is raised. Between each rubber hose 160 and exterior wall 60 are rubber sealing gaskets 170 .
[0038] FIG. 5D shows yet a further embodiment of sealing means, in which gasket 55 on pivotable member 180 , is positionable under inner tank wall 40 , after inner tank wall 40 has been raised. Inner tank wall 40 is then sealed using gravity as inner tank wall 40 rests on pivotable member 180 which pivots on hinge 185 .
[0039] Containment tray 70 is positioned around the base 80 of exterior tank wall 60 to contain any leakage that may slip through the seals at the junction of interior tank wall 40 and exterior wall 60 . A built in transfer pump (not shown) may be present to transfer any fluid collected in the containment tray back into the main tank 10 .
[0040] Exterior wall 60 includes a plurality of flanged and valved connection ports (not shown) to allow for liquid transfer from the tank and reception of liquids from other sources.
[0041] FIG. 6 shows an alternative embodiment of tank 10 in which outer wall 200 is raise by hydraulic lifts 50 relative to inner wall 210 . An example of sealing means for this embodiment is shown in FIG. 7 , in which inward extension 220 at the bottom of outer wall 200 meets outer facing extension 230 of inner wall 210 . Rubber inflatable seal members 240 , as shown in FIG. 8 , may be positioned on either inward extension 220 or outward extension 230 facing the other extension. When the rubber seal members 240 meet inward extension 220 , members 240 flatten, and may be inflated by air or liquid, creating a seal between inner wall 210 and outer wall 200 .
[0042] Tank floor 90 may be gently sloped and have a liquid outlet at the base 80 to allow for ease of extraction of the liquid therein. Built in pumping systems (not shown) may be present to allow transfer of liquid between tanks 10 , transfer of liquid off site, and circulation of liquid through heaters and pipelines to prevent freezing. Alternatively, the pumping systems may be positioned nearby tank 10 , and in liquid communication with tank 10 via hoses and the like.
[0043] When fracking job is finished, tank 10 is drained, inner tank wall 40 (or outer tank wall 200 ) is lowered to transport height, and tank 10 is winched onto standard high-bed tractor trailer, and can be moved from the site. Typical volume of tank 10 would be 500 m 3 , based on a two tier tank wall design.
[0044] FIG. 9 shows a side cross sectional view of another embodiment of a tank 10 according to the invention. In this embodiment of tank 10 , outer wall 200 is elevatable. Foldable walking platform 215 is positioned around the interior of inner tank wall 210 to allow users access to tank 10 , Outer wall 200 is shown in elevated position in dashed lines, and in unelevated position in solid lines.
[0045] FIG. 10 is a detailed view of C in FIG. 9 , showing the sealing means. Guide 310 acts as a pinning plate to guide walls 200 and 210 into position. Pins 315 are then used to secure walls 200 and 210 , by passing pins 315 , 316 through aligned apertures (not shown) in each wall 200 , 210 . Pin 315 may be fixed in place while pin 316 is removable to allow outer wall 200 to be elevated or lowered. Seal members 240 are secured to the top of inner wall by screws or the like.
[0046] FIG. 11 shows a detailed view of B in FIG. 9 , showing base 325 of walking platform 215 secured to inner wall 210 .
[0047] FIG. 12A is a cross sectional top view of elevated outer wall 200 showing links 360 . Links 360 are secured to outer wall 200 by pins 315 , 316 .
[0048] FIG. 12B is a detail of A showing the bottom portion of inner wall 210 and outer wall 200 . Drip tray 330 provides secondary liquid containment and has lip 335 extending outwardly from outer wall 200 .
[0049] FIG. 13 is a perspective view of tank 10 showing the frame of the inner wall 210 and outer wall 200 . Extension 400 provides support and stability to tank 10 . Pipes 410 allow for intake or removal of water or another fluid. Ladder 420 allows workers to reach the bottom of tank 10 .
[0050] The bottom of tank 10 is supported by bottom cross beams 430 . Support beams 440 extend vertically to support inner tank wall 210 . Door 450 allows access to the interior of tank 10 , for cleaning, or for a vacuum truck operator. Door 450 may be configured so that it cannot be opened when tank 10 is full to provide safety for workers nearby.
[0051] Outer wall 200 is supported vertically by vertical support beams 460 and upper horizontal cross members 470 and lower horizontal cross members 480 . Upper frame member 490 maintains the shape of outer wall 200 . Tank 10 is generally made of steel, with the exterior of outer wall 200 painted and the interior of inner wall 210 having an anti-corrosion coating.
[0052] Ring 500 surrounds the top of inner wall 210 . Links 360 extend upwardly from ring 500 . Attached to support beams 440 is walking platform 215 .
[0053] FIGS. 14A , 14 B and 14 C show the process by which outer wall 200 raises. FIG. 14A shows outer wall in an unelevated state. Guide 860 , which may be a pipe, has a links 890 at the top and bottom to allow it to be secured to or detached from wall 200 . Wall 200 is positioned in-between guide 860 and guide 880 , and is secured to hydraulic lift 338 . Guide 880 is extendible and may rise with lift 338 . The lower end of guide 880 is fixed in position.
[0054] FIG. 15 shows gusset 390 which is used by hydraulic lift 338 to raise wall 200 . Guides 860 and 880 are on opposite sides of wall 200 . Corners of tank 10 are cured to correspond to the bending of seals 240 , which may not always permit a square corner.
[0055] When inner wall 210 and outer wall 200 are pinned together (i.e. the elevatable wall is not in an elevated position and the walls 200 . 210 are secured by pins), hydraulic lift 338 can expand freely downward and act as a jack to lift the entire tank structure 10 , as shown in FIG. 14B . This is used for loading and unloading tank 10 onto a trailer. The hydraulic lifts elevate tank 10 so that a trailer can be positioned underneath it.
[0056] Hydraulic lifts 50 also lift outer wall 200 from the inner wall 210 . After tank 10 is unloaded, it is lowered to the ground. The two walls 200 , 210 are now unpinned. Now when the hydraulic lifts 50 jacks extend, they lift outer wall 200 and separate the two walls 200 , 210 .
[0057] The above-described embodiments have been provided as examples, for clarity in understanding the invention. A person with skill in the art will recognize that alterations, modifications and variations may be effected to the embodiments described above while remaining within the scope of the invention as defined by claims appended hereto. | A tank is provided, including a tray positioned on a skid; an outer tank wall positioned within the tray; an inner tank wall positioned within the first outer tank wall; wherein the outer tank walls is moveable from a first position wherein the inner tank wall is substantially contained within the outer tank wall; and a second position wherein the moveable outer tank wall is elevated, thereby increasing the height and storage capacity of the tank. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method and apparatus for chemically treating an acidic water stream. More particularly, the present invention relates to a portable apparatus which can be easily transported to a remote location for treating an acidic water stream with a minimal amount of human supervision. Furthermore, the apparatus uses the energy of the flowing water in the stream to disperse a treatment chemical agent into the acidic water stream.
2. Description of the Prior Art
Acidic water streams have frequently occurred as a result of coal mining operations. The acidic water streams occurred when natural water flowed through mines and piles of waste materials from mines. The flowing natural water dissolves and carries away various compounds when the water contacts the minerals in the mine or mine waste materials. In particular, if the mining operation involves high sulfur coal then the water will dissolve and carry away sulfur compounds. The dissolved sulfur increases the acidity of the water streams.
The resulting highly acidic water streams represent a significant environmental detriment to water quality in areas where mining operations for high sulfur coals occur. When the highly acidic water stream flows into naturally occurring water streams it greatly diminishes or eliminates the ability of that stream to support aquatic life such as fish. In fact, this form of pollution is common in areas of Pennsylvania, West Virginia and Ohio where high sulfur coals are mined, and is evidenced by orange or yellow colored streams and rivers (i.e., the orange and yellow coloring comes from the precipitation of iron sulfates).
As a result of enactment of various environmental statutes, the operators of high sulfur coal mining operations have developed methods for treating acidic water streams that flow from mines and mine waste piles. In particular, these methods conventionally involve collecting the water into large ponds and then treating the pond with treatment chemicals before discharging the treated water from the pond into naturally occurring streams and rivers. One common treatment involves the addition of lime to the pond where the acidic water is impounded. The lime neutralizes the acidity of the water. This method of treatment suffers from the disadvantage of providing poor mixing between the lime and the water in the pond because the pond water is relatively still. Consequently, excessively large amounts of lime are required to neutralize the acidic water in the pond.
Other methods and apparatus have also been used for neutralizing acid mine drainage water. For example, U.S. Pat. No. 3,142,639 generally describes a method for neutralizing acid mine drainage in which the acid mine drainage is transferred to a mixing container, a solid neutralizing agent is fed into the mixing container from a hopper, the acid mine drainage and the neutralizing agent are mixed in the mixing container, and the treated acid mine drainage water is discharged into a settling basin. The apparatus for practicing this method includes a pump for both transferring the acid mine drainage to the mixing container and transferring the neutralized acid mine drainage water to the settling basin. The pump is either electrically powered or powered by an internal combustion engine.
Likewise, U.S. Pat. No. 4,116,834 describes an apparatus which can be used for neutralizing acid mine drainage by feeding lime from a hopper into a lime slurry tank where the lime is mixed with water to form a slurry and then feeding the lime slurry into a mixing tank where the lime slurry is mixed with the water to be treated. The apparatus of this patent includes a motor driven feeder for transferring the lime to the lime slurry tank and motor driven mixers for the lime slurry tank and the mixing tank. These motors are electrically powered.
Other references also describe similar methods for treating a water stream. For example, U.S. Pat. Nos. 1,722,571; 3,456,801; and 3,595,393 generally describe a water treatment method in which a solid treating agent is added to a portion of the water to be treated in a mixing container and then discharged into another body of water.
The methods and apparatus described in these patents for treating water include the step of taking a portion of the water from the body of water to be treated and mixing the treating agent with that portion of the water in a mixing container before discharging the treated portion of the water back to the overall body of water. This mixing step introduces additional mechanical complexity to the apparatus. Moreover, most of these apparatus and methods require an electrical power supply or an internal combustion engine to power various parts of the apparatus. Thus, these conventional methods and apparatus for treating water streams require frequent human supervision due to their mechanical complexity and due to their use of electrical power or internal combustion engines for power.
Consequently, there is a need for improved apparatus and methods for effectively treating acidic water streams from coal mining operations. In particular, such apparatus would be easily portable to remote locations, require no electrical or internal combustion engine power sources, and be mechanically simple to minimize human supervision.
SUMMARY OF THE INVENTION
The present invention provides an apparatus and method which is useful for treating a flowing water stream with a chemical treatment agent. In particular, the present invention is useful for treating acidic water streams from coal mining operations with a solid chemical agent such as pelletized lime. The present invention overcomes disadvantages of conventional methods for treating acidic mine streams which require a mixing step. Further, the present invention does not require electrical power supplies or internal combustion engines as do conventional apparatus. Instead, the present invention utilizes the energy of the flowing water stream to power the apparatus of the present invention. In addition, the apparatus of the present invention is easily transported to remote locations and requires minimal human supervision due to its mechanical simplicity and use of a flowing water stream as a power source.
The apparatus of the present invention generally comprises a means for containing chemical treatment agent, a means for discharging the chemical agent from the containing means to the flowing water stream, a means for generating mechanical energy, and a means for transferring the mechanical energy to the discharging means. The means for discharging the chemical agent into the flowing water stream provides a rate of discharge which is proportional to the mechanical energy transferred to the discharging means. In addition, the mechanical energy generating means must generate its energy from the flowing water stream, and be adjustable to provide variable amounts of mechanical energy to the discharging means thereby varying the rate of discharge of the chemical agent.
Preferably, the means for containing the chemical treatment agent is a hopper with a lid for placing chemical agent into the hopper and an opening where chemical agent can be removed from the hopper.
The means for discharging the chemical agent into the flowing water stream preferably is a pipe enclosing an auger such that the pipe connects with the opening in the hopper and the pipe further includes an opening for discharging the chemical agent to the flowing water stream. The auger is rotatable, and when rotated, chemical agent from the hopper is transferred by the auger from the hopper out of the opening in the pipe and onto the surface of the flowing water stream.
The means for generating mechanical energy from the flowing water stream preferably comprises a water wheel. The water wheel generates mechanical energy from contact with the flowing water stream or a portion of the flowing water stream. Mechanical energy from the water wheel is then transferred to the discharging means.
Preferably, the apparatus of the present invention further includes a means for channeling the flowing water stream into proximity with the discharging means. The channeling means comprises a conduit with a wide mouth which funnels flowing water from the stream into a narrow channel. The conduit is positioned so that the narrow channel with the concentrated flow of water is immediately proximate to the discharge means thereby providing exposure of the chemical agent to an increased amount of water from the flowing water stream.
The method of the present invention generally comprises the steps of containing the chemical treatment agent above the flowing water stream, generating an adjustable amount of mechanical energy from the flow of a portion of the flowing water stream, and using the generated mechanical energy for discharging the chemical treatment agent into the flowing water stream so that the chemical agent is discharged at a rate proportional to the amount of mechanical energy derived from the flowing water stream. In addition, the method preferably includes the step of channeling the flowing water stream into proximity with the point where the chemical agent is discharged into the flowing water stream.
Preferably both the method and apparatus of the present invention use chemical treatment agent in pellet form.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention can be better understood by reference to the drawings in which:
FIG. 1 is a front view of the apparatus of the present invention;
FIG. 2 is a back view of the apparatus of the present invention;
FIG. 3 is a side cross-sectional view of the discharging means of the present invention;
FIG. 4 is an end cross-sectional view of the discharging means of the present invention;
FIG. 5 is a top view of the discharging means of the present invention as seen from inside the containing means;
FIG. 6 is a side cross-sectional view of the means for generating mechanical energy of the present invention;
FIG. 7 is a perspective view of the water channeling means of the present invention;
FIG. 8 is a cut-away perspective view of the top of the containing means of the present invention with the lid open.
FIG. 9 is a cut-away perspective view of the present invention showing a step and platform.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Generally, the apparatus of the present invention includes a means for containing a chemical treatment agent, a means for discharging the chemical agent into a flowing water stream, a means for generating an adjustable amount of mechanical energy from the flowing water stream, and a means for transferring mechanical energy from the generating means to the discharging means so that the rate of discharge of the chemical agent is proportional to the amount of mechanical energy transferred to the discharging means.
Referring now to FIGS. 1 and 2, front and back views of the apparatus of the present invention are shown. The apparatus includes a hopper 10 with an attached lid 12. The top of the hopper 10 is configured like a peak with two surfaces. The lid 12 makes up one surface of the peaked top of the hopper 10. The other surface 13 of the peaked top is contiguous with the rest of the body of the hopper 10. The lid 12 is attached by hinges 11 to top surface 13 of the hopper 10. The lid 12 includes a handle 14 for manually raising the lid 12 by rotating it on its hinges 11 so that the hopper 10 can be filled with the chemical treatment agent.
The hopper 10 further includes a top portion 16 and a bottom portion 18. The top portion 16 of the hopper 10 has a square cross section with vertical sides. The bottom portion 18 of the hopper 10 has three sides which slant inwards toward a common point and a fourth side which is vertical. Thus, the overall shape of the bottom portion 18 of the hopper 10 is funnel-like. A long, narrow rectangular opening is located at the lowest point of the funnel-like bottom portion 18 of the hopper 10. This geometry of the hopper insures that any chemical agent in the hopper 10 will be channeled to the opening at the lowest point of the funnel-like bottom portion 18 of the hopper 10. Preferably, the hopper 10 is constructed from 1/8th inch steel sheet. The hopper 10 functions as a means for containing the chemical treatment agent.
Referring to FIGS. 3, 4 and 5, the apparatus of the present invention includes a means 20 for discharging the chemical treatment agent from the hopper 10 into the flowing water stream. The discharging means 20 includes a pipe 22 which encloses an auger 24 attached to a shaft 28. An opening is cut into the pipe 22 which matches the long, narrow rectangular opening in the bottom portion 18 of the hopper 10. The edge of the opening in the pipe 22 is then welded to the edge of the opening in the bottom portion 18 of the hopper 10. In this manner the pipe 22 and auqer 24 are supported by the hopper 10. This configuration of the pipe 22 and hopper 10 allows chemical treatment agent from the hopper 10 to be transferred into the interior of the pipe 22.
As shown in FIG. 4, the opening in the bottom portion 18 of the hopper 10 is not oriented horizontally. Instead, the opening is oriented at an angle so that when the pipe 22 is welded to the bottom portion 18 of the hopper 10 one side of the bottom portion 18 of the hopper 10 extends and is welded to the bottom of the pipe 22, and the opposing side of the bottom portion 18 of the hopper 10 extends and is welded to the top edge of the pipe 22. This geometry substantially insures that the chemical treatment agent is transferred into the side of the pipe 22 and auger 24 thereby preventing the weight of the chemical treatment agent from resting on top of the auger 24. If the opening between the pipe 22 and bottom portion 18 of the hopper 10 were oriented horizontally and above the auger 24, then the weight of the chemical treatment agent would tend to interfere with the rotation of the auger 24.
The pipe 22 is oriented horizontally and includes a short vertical pipe 26 at one end of the pipe 22. The vertical pipe 26 communicates with the interior of the main pipe 22 and opens downwards towards the surface of the flowing water stream. The shaft 28 extends at one end into bushing 30 which is fixed at one end of pipe 22. As shown in FIG. 3, the shaft 28 extends through bushing 32 which is fixed at the other end of the pipe 22. Thus, this end of the shaft 28 extends beyond the pipe 22, and is coupled to the shaft of a gear box 34 by a flexible coupling 36.
When the shaft 28 and auger 24 are rotated, the chemical treatment agent is transferred from the hopper 10 along the pipe 22 until it falls out of vertical pipe 26 onto the surface of the flowing water stream. It should be appreciated that the rate at which chemical treatment agent is discharged by the auger 24 is proportional to the rate of rotation of the auger 24. The pipes 22 and 26, auger 24, and shaft 28 jointly function as means for discharging chemical treatment agent from the hopper 10 to the flowing water stream.
Preferably, pipes 22 and 26 consist of 4 inch steel tubing which is 3/16th inch thick. The auger 24 is nominally 4 inches in diameter, however the outer diameter of the auger 24 is actually less than 4 inches so that about a 1/8th inch clearance is provided between the outer diameter of the auger 24 and the inner diameter of the pipe 22. The shaft 28 is 3/4 inch steel rod.
Preferably, a plastic pipe 38 is loosely fitted within vertical pipe 26. The plastic pipe 38 is useful for protecting the chemical treatment agent from dispersion by wind as it falls out of the vertical pipe 26 onto the surface of the flowing stream. It should be appreciated that the plastic pipe 38 is cut to a length such that the bottom of the plastic pipe 38 will be located immediately above the surface of the flowing water stream. In addition, the plastic pipe 38 can be positioned within the pipe 26 to adjust to various heights of the surface of the flowing water stream.
Referring to FIG. 2, the gear box 34 includes a sprocket 40 and a shaft which connects to flexible coupling 36. The sprocket 40 is driven by a chain 42. The chain 42 is in turn driven by a sprocket 44 attached to water wheel 46. The chain 42 and sprockets 40 and 44 are protected by an expanded metal guard (not shown). The gear box 34, flexible coupling 36, and chain 42 jointly function as a means for transferring mechanical energy from the water wheel 46 to the shaft 28 of the auger 24.
Any commercially available gear box may be used for gear box 34. In particular, a gear box manufactured by Hub City with a 20 to 1 gear ratio has been found to be effective for use in the apparatus of the present invention.
Referring now to FIG. 6, the water wheel includes two disks 48 of the same size which are spaced about 6 inches apart, a band 50 which is located about 3 inches in from the outer circumference of the two disks 48 and interconnects the two disks 48 with each other, and a series of plates 52 which extend outwards at an angle from the band 50 in between the two disks 48 and form receptacles for receiving water. A shaft 54 extends through the center of the two disks 48. The sprocket 44 connects to the shaft 54 on one side of the water wheel 46. A cover 56 fits over and around the water wheel 46 from a position of about 30° through a position of about 210° going counterclockwise. A pipe 58 runs parallel to the top of the cover 56 and then angles down to connect with the cover 56 at a point at the top of the water wheel 46. The pipe 58 includes a valve 60 for varying the amount of water flowing through the water wheel 46. A ball valve has been used effectively for valve 60. One end of a hose (not shown) would be connected to the valve 60 and the other end of the hose would be placed in the flowing water stream upstream of the apparatus. Thus, the hose would provide a flow of water for the water wheel 46.
In this manner, water flows through the pipe 58 and enters the top of the water wheel 46 where it impacts against the receptacles and causes the water wheel 46 to turn thereby generating mechanical energy. It should be appreciated that the mechanical energy generated by the water wheel 46 is proportional to the amount of water impacting the water wheel. As the water wheel 46 turns, the receptacles filled with water empty their water as they approach the bottom point of the water wheel's rotation. Thus, the water wheel 46 functions as a means for generating mechanical energy from a portion of the flowing water stream.
In addition, a small threaded drain plug 62 is provided for the water wheel 46. The threaded drain plug 62, when removed, communicates with the interior space formed by the two disks 48 and the band 50. Preferably, the threaded drain plug 62 is located as close to the band 50 as possible. Consequently, water which may accumulate inside the water wheel 46 due to leakage may be removed. The water wheel cover 56 and pipe 58 may be made out of normal steel. Preferably, however, stainless steel is used to reduce corrosion from contact with the acidic water stream.
Referring to FIG. 7, a means for channeling the flow of water beneath the apparatus of the present invention is shown. The channeling means consists of a three sided conduit 64 which has a large fluted end 66 and a smaller fluted end 68. The conduit 64 is placed into the flowing water stream such that the large fluted end 66 faces upstream and the small fluted end 68 faces downstream. The apparatus of the present invention is then positioned over the conduit 64 such that the vertical pipe 26 and plastic pipe 38 are positioned immediately above the narrow part of the conduit 64 adjacent to the smaller fluted end 68. The conduit 64 is preferably made from moldable plastic. As a result of the use of the conduit 64 the chemical agent discharged by the apparatus of the present invention will contact an increased amount of water due to the channeling effect of the conduit 64 than would otherwise occur by discharging the chemical agent onto the surface of the flowing stream as it naturally exists.
Referring now to FIG. 8, a detailed perspective view of the top of the hopper 10 is provided with the lid 12 open. Inside of the top of the hopper 10 a cross member 70 horizontally connects each of the two peak sides of the top portion 16 of the hopper 10. Attached to the top of the cross member 70 is an eye 72. A crane with a hook may be connected to the eye 72 and thereby the crane may be used to lift and position the apparatus of the present invention as desired.
In addition, the lid 12 of the hopper 10 includes a rod 74 which is pivotally attached to one side edge of the lid 12. The other end of the rod 74 engages a slotted bracket 76 which is attached to a peaked side of the top portion 16 of the hopper 10. This slotted bracket 76 includes a cutout notch such that the lid 12 of the hopper 10 can be raised and locked in an open position by placing the end of the rod 74 in the cutout notch of the slotted bracket 76.
Referring to FIGS. 1 and 2, the hopper 10, water wheel 46, and gear box 34 are supported above the flowing water stream by a base. The base includes four vertical members 82, 83, 84 and 85 which are welded to the corners of the top portion 16 of the hopper 10. Vertical members 82 and 83 at the front of the apparatus are welded to a base member 86 as shown in FIG. 1. Likewise, vertical members 84 and 85 at the back of the apparatus are welded to base member 87 as shown in FIG. 2. Two members 90 and 91 are also welded to base members 86 and 87, respectively, and rise upwards at an angle such that the tops of each member 90 and 91 are welded to the sides of the cover 56 of the water wheel 46.
Two members 88 and 89 are welded to members 90 and 91 and run parallel to base members 86 and 87. The members 88 and 89 are welded to two cross braces (not shown) which run horizontally between vertical members 82 and 84, and 83 and 85, respectively. In addition, the members 88 and 89 include brackets 92 and 93 with ball bearings in which the shaft of the water wheel 46 rotates. The members 88 and 89 are welded to the front and back sides of the hopper 10 at the bottom portion 18 of the hopper 10. The gear box 34 is supported by a right angle member (not shown) which extends downwards and then horizontally underneath the gear box 34 from the cross brace (not shown) between vertical members 82 and 84. Members 86, 87, 88, 89, 90 and 91 along with the cross braces (not shown) are made from square steel tubing. Vertical members 82, 83, 84, and 85 are made from 1/4th inch angle iron.
Referring to FIG. 9, preferably the apparatus of the present invention includes a platform 78 which is mounted on the front side of the apparatus next to the hopper 10. The platform 78 is positioned on the side of the hopper 10 on which the lid 12 is located. In this manner, a person may stand on the platform 78 to place the chemical agent into the hopper 10 while the lid 12 of the hopper 10 is in an open position. In addition, a step 80 is attached to the apparatus of the present invention to assist a person in stepping up to the platform 78. The platform 78 and the step 80 are made from a piece of grid or grate steel. Preferably, the platform 78 is hingedly mounted to the apparatus of the present invention such that the platform can be swung down so that it does not extend beyond the sides of the hopper 10.
Overall, the apparatus of the present invention has dimensions of about 90 inches long by 46 inches wide by 69 inches high. This insures that the apparatus of the present invention can be moved to remote stream locations by vehicles as small as a pickup truck. The overall weight of the apparatus of the present invention is about 930 pounds. Preferably, the weight of the apparatus is kept at a minimum to increase the portability of the apparatus of the present invention.
The apparatus of the present invention has proven to work most effectively with pelletized chemical agents. In particular, a commercially available pelletized hydrated lime called pebble lime can be discharged effectively by the apparatus of the present invention into a flowing water stream. Early experiments using commercially available hydrated lime in powder form did not provide completely satisfactory discharge of the lime into a flowing water stream. In particular, the hydrated lime in powder form tended to bridge in the bottom portion of the hopper so that no lime was discharged to the water stream.
It should be appreciated that the description of the preferred embodiments is illustrative of the invention. Other modifications and changes could be made by one skilled in the art without departing from the invention. For example, the plates of the water wheel could be arranged in a different manner. | An apparatus and method are described for treating a flowing water stream with a chemical treatment agent. In particular, the apparatus includes a hopper for containing the chemical treatment agent, an auger for discharging the chemical treatment agent from the hopper into the flowing water stream, and a water wheel which provides an adjustable amount of mechanical energy for driving the auger to discharge the chemical agent into the flowing water stream at a rate proportional to the amount of mechanical energy provided by the water wheel. The apparatus is relatively light in weight with minimal dimensions to provide portability for locating the apparatus in remote locations. Further, the apparatus requires minimal human supervision because it uses the flowing water stream as an energy source and is mechanically simple. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a process for producing a fine tungsten carbide powder suited for producing a fine cemented carbide having a high strength, and to a high-performance fine tungsten carbide powder produced by the process.
[0003] 2. Description of the Related Art
[0004] It has been well known that various cutting tools and wear-resistant tools are generally made from a tungsten carbide-based cemented carbide (hereinafter referred to as a cemented carbide) having a high strength, and that a fine tungsten carbide powder having an average particle size of 0.8 μm or less is used as a raw powder in the production of these tools for the purpose of securing a high strength.
[0005] As a process for producing the fine tungsten carbide powder, for example, various processes have been suggested, including processes described in U.S. Pat. No. 4,008,090 and Japanese Unexamined Patent Application, First Publication No. Sho 50-92899.
[0006] Recently, weight reduction, size reduction, and thinning have strongly been required in cutting tools and wear-resistant tools, and the shapes thereof have become progressively diversified and complicated. Therefore, a higher strength has been required for the cemented carbides which constitute these tools.
BRIEF SUMMARY OF THE INVENTION
[0007] To develop a cemented carbide having a higher strength from the above points of view, the present inventors have focused research on a fine tungsten carbide powder using a raw powder of a cemented carbide and have obtained the research
[0008] results shown in the following (a) to (d). (a) The process for producing a conventional fine tungsten carbide powder includes, for example, a process of adding a carbon powder to a tungsten oxide powder as a raw powder and milling the mixed powder, followed by milling, reduction, and further carburization, as disclosed in U.S. Pat. No. 4,008,090. In the case of milling using a ball mill, contamination by metal impurities such as iron, cobalt, nickel and chromium from stainless steel containers and cemented carbide balls cannot be avoided. As a result, it becomes impossible to maintain a high purity of 99.9% or higher and coarse WC particles are locally produced during the reduction and carburization by the influence of these metal impurities (when using a powder containing the coarse WC particles as a raw material, a reduction in strength is likely to be caused by the coarse WC particles as origins of fractures). Therefore, it is difficult to produce a high-performance fine tungsten carbide powder.
[0009] (b) As disclosed in Japanese Unexamined Patent Publication, First Publication No. Sho 50-92899, there is also suggested a process of carburizing a precursor, which is obtained by drying a mixture of an ammonium paratungstate and a cobalt salt, with a gas to obtain a composite powder of tungsten carbide and cobalt. According to this process, cobalt is likely to cause a sintering phenomenon during the carburization and coarse WC particles are likely to be locally produced. Furthermore, very fine cobalt particles (at nanometer level) are dispersed in tungsten carbide particles. In the case in which the cemented carbide is produced by using the fine cobalt dispersed tungsten carbide powder, the thermal conductivity is reduced. When using the resulting cemented carbide as a cutting tool, the strength of the edge portion is reduced at high temperatures during the use of the tool, thus causing breakage and chipping.
[0010] (c) According to a process for producing a fine tungsten carbide powder, which comprises mixing an aqueous solution of ammonium tungstate as a starting material with a carbon powder to form a slurry, drying the slurry to form a precursor mixed with the carbon powder, heating the mixed precursor in an inert gas atmosphere, thereby causing the reduction and carburization by means of the carbon powder in the mixed precursor to produce a reduction and carburization product composed mainly of tungsten carbide, and finally mixing the reduction and carburization product with the same carbon powder used in the preparation of the slurry in a proportion so that W:C is substantially 1:1, and subjecting the mixture to a carburization in a hydrogen atmosphere, it becomes possible to form a high-purity, fine and high-performance tungsten carbide powder which contains less metal impurities and less coarse WC particles, and which also contains nitrogen and oxygen in trace amounts.
[0011] (d) The cemented carbide produced by using, as a raw powder, the fine tungsten carbide powder obtained in (c) above has a higher strength as compared with a cemented carbide produced by using a fine tungsten carbide powder having an average particle size of 0.8 μm or less produced by a conventional process, or a composite powder of a fine tungsten carbide particle and cobalt having an average particle size of 0.8 μm or less. When used as a cutting tool and a wear-resistant tool, it exhibits superior performance without causing breakage and chipping of the edge portion.
[0012] The present invention has been made based on the research results described above and is directed to a process for producing a fine tungsten carbide powder, which comprises the steps (a) to (e) of:
[0013] (a) mixing an aqueous ammonium tungstate solution (an aqueous solution of at least one of ammonium metatungstate and ammonium paratungstate, preferably in a concentration within a range of 20-70% by weight) preferably having a purity of at least 99.9% by weight, and more preferably at least 99.99% by weight, with a carbon powder (preferably carbon black powder) preferably having a purity of at least 99.9% by weight, and more preferably at least 99.99% by weight, in a proportion required to reduce and carburize ammonium tungstate (preferably an atomic ratio of carbon to tungsten in ammonium tungstate (C/W) in a range of 3-4) to form a slurry,
[0014] (b) drying the slurry at low temperature (preferably not more than 350° C.) to prepare a precursor,
[0015] (c) subjecting the precursor to a reduction and carburization for heating to a temperature, at which a reduction and carburization proceed (preferably within a range of 900-1600° C., and more preferably within a range of 1000-1200° C.), in a non-oxidizing gas atmosphere (preferably in a mixed gas of a nitrogen gas at normal pressure and a CO gas produced by the reaction) to form a reduction and carburization product, which is substantially free of oxides,
[0016] (d) mixing the reduction and carburization product with a carbon powder (preferably carbon black powder) preferably having a purity of at least 99.9% by weight, and more preferably at least 99.99% by weight, in a proportion required to carburize a W 2 C component and/or a W component in the reduction and carburization product into WC, and
[0017] (e) subjecting the reduction and carburization product mixed with the carbon powder to a carburization for heating to a temperature, at which a carburization proceeds (preferably within a range of 900-1600° C., and more preferably within a range of 1000-1400° C.), in a hydrogen atmosphere, thus producing a fine tungsten carbide powder having an average particle size of 0.8 μm or less, and to a high-performance fine tungsten carbide powder produced by the process.
[0018] The process of the present invention can provide a high-purity fine tungsten carbide powder capable of producing a high-strength cemented carbide, and thus it contributes to an increase in strength of various cutting tools and wear-resistant tools in which the cemented carbide is widely used.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The reason why manufacturing conditions were decided as described above in the process of the present invention will be explained.
[heading-0020] (a) Kind and Purity of Raw Materials
[0021] Ammonium tungstate includes ammonium metatungstate and ammonium paratungstate. Both of these can be used as a raw material, but ammonium metatungstate has a higher solubility in water at room temperature. Therefore, when using ammonium paratungstate, warm water at a proper temperature is used, if necessary. To obtain high-purity WC, the purity (content of tungsten in the total metal component) must be controlled to at least 99.9% by weight, and preferably at least 99.99% by weight.
[0022] Since the carbon powder must be finely dispersed in the aqueous ammonium tungstate solution as much as possible, a carbon black powder is preferred to obtain a fine powder. For the same reason as in the case of ammonium tungstate, the purity is preferably at least 99.9% by weight, and more preferably at least 99.99% by weight.
[0023] The process of the present invention does not require any mechanical milling step and therefore contamination by metal impurities from the milling step can be avoided, thus making it possible to produce a high-purity tungsten carbide powder.
[heading-0024] (b) Content of Ammonium Tungstate in Aqueous Solution
[0025] Even if the content is less than 20% by weight and exceeds 70% by weight, it becomes difficult to obtain a slurry containing a carbon powder dispersed uniformly therein. Therefore, the content is preferably within a range of 20-70% by weight.
[heading-0026] (c) Content of Carbon Powder in Slurry
[0027] When the atomic ratio of carbon to tungsten in ammonium tungstate (C/W) is less than 3, oxides remain in the reduction and carburization product. When oxides exist in the reduction and carburization product, the oxide reacts with hydrogen in the atmosphere in the following step of carburizing with heating to form H 2 O, which promotes grain growth of the tungsten carbide powder. Therefore, the average particle size increases to produce WC particles wherein grain growth locally occurs. On the other hand, when the content exceeds 4, the content of free carbon in the reduction and carburization product increases. Therefore, the content is-preferably within a range of 3-4.
[heading-0028] (d) Drying Temperature
[0029] The slurry is dried by a simple heating process in air, or by a spray-dry process. When the heating temperature exceeds 350° C., tungsten oxide produced by the decomposition of ammonium tungstate causes grain growth, thus making it difficult to form a fine reduction and carburization product. Therefore, the heating temperature is preferably 350° C. or less
[heading-0030] (e) Temperatures of Reduction and Carburization Treatment and Carburization Treatment
[0031] When each temperature is lower than 900° C., the reduction and the carburization cannot proceed sufficiently. On the other hand, when each temperature exceeds 1600° C., the grain rapidly grows in both reactions, thus making it impossible to control the average particle size to 0.8 μm or less. In both cases, the temperature is preferably within a range of 900-1600° C. In consideration of the economical reduction and carburization time and the degree of grain growth of the respective reaction products, the reduction and carburization temperature and the carburization temperature are more preferably within a range of 1000-1200° C. and 1000-1400° C., respectively.
[heading-0032] (f) Average Size of WC Particles
[0033] In general, the cemented carbide produced by using a WC powder having a small average particle size as a raw material has a higher strength. Therefore, in the tungsten carbide powder for the objective fine alloy of the present invention, the average particle size of WC particles is preferably controlled to 0.8 μm or less.
[heading-0034] (g) Maximum Size of WC Particles
[0035] Even if the cemented carbide is produced by using a fine tungsten carbide powder having an average particle size of 0.8 μm or less as a raw material, coarse WC particles included in the cemented carbide acts as the origins of fractures, thereby causing reduction in strength. In the desired fine alloy of the present invention, the maximum particle diameter of WC particles is preferably controlled to 1 μm. As the average particle size of the fine powder, a value converted from the specific surface area in accordance with the BET process or a value measured by SEM is preferably used.
[heading-0036] (h) Content of Nitrogen and Oxygen in WC
[0037] Regarding the WC powder produced by the process of the present invention, only a WC phase is observed by X-ray diffraction. When treated in an atmosphere containing nitrogen at normal pressure during the reduction and carburization, the resulting product contains a trace amount of nitrogen without being treated in nitrogen under pressure. Also after the completion of the carburization, a trace amount of oxygen remains. These components inhibit sintering during the production of the cemented carbide and also have an operation of inhibiting grain growth. Therefore, the nitrogen content is preferably within a range of 0.05-0.30% by weight, and preferably within a range of 0.08-0.20% by weight, while the oxygen content is preferably within a range of 0.10-0.60% by weight, and more preferably from 0.10-0.35% by weight. The nitrogen content and the oxygen content can achieve the desired content by controlling the heating conditions of the reduction and carburization and those of the carburization. These nitrogen and oxygen components are those which exist in the crystal lattice. Because of the existence of nitrogen and oxygen in the content within the above range, the WC powder has a lattice constant of 0.29020-0.29060 nm for the a-axis and that of 0.28380-0.28420 nm for the c-axis, unlike the standard value in accordance with Joint Committee of Powder Diffraction Standard (JCPDS) (25-1047).
EXAMPLES
[0038] Using ammonium metatungstate (AMT) and ammonium paratungstate (APT) each having a purity shown in Table 1 (percentages are by weight unless otherwise specified), pure water was added to prepare aqueous solutions each having a predetermined concentration within a range of 20-70% by weight. To each of these aqueous solutions of various concentrations, a carbon black (CB) having a purity shown in Table 1 was added in the proportion (atomic ratio of C to W) shown in Table 1, followed by mixing using a stirrer for one hour to form a slurry. Among these slurries, the slurry having a concentration within a range of 20-45% by weight is spray-dried using a spray-dryer (heating temperature set to 300° C.), while the aqueous 50-70 wt % solution was heated at low temperature using a hot-air (heating temperature set to 150° C.) to prepare mixed precursors of AMT or APT and the CB powder.
[0039] Then, the resulting mixed precursors were subjected to the reduction and carburization using a fixed bed furnace in a nitrogen gas atmosphere under 1 atmosphere pressure under the conditions of a predetermined temperature within a range of 900-1600° C. for one hour (the same conditions may be used even when using a horizontal type rotary furnace).
[0040] The qualitative analysis of the reduction and carburization products formed by the reduction and carburization was conducted by X-ray diffraction. As a result, it has been confirmed from the resulting composition formula that all reduction and carburization products are mainly composed of WC and are substantially free of oxides.
[0041] Subsequently, a CB powder which is the same as that added to the above aqueous solutions of ammonium tungstates was add to the above reduction and carburization products in the proportions shown in Table 1 (which are proportions required to substantially carburize W 2 C and W in the reduction and carburization products into WC in the composition formula and denotes a proportion of the content to the total amount of the reduction and carburization products). After mixing using a stirrer, the mixture was subjected to a carburization using the same fixed bed furnace (a horizontal type rotary furnace may be used) in a hydrogen gas atmosphere under 1 atmosphere pressure under the conditions of a predetermined temperature within a range of 900-1600° C. for 0.5-1 hours, thereby carrying out the processes 1 to 15 of the present invention.
[0042] With respect to the carburization products obtained by the processes 1 to 15 of the present invention, X-ray diffraction was conducted. As a result, only diffraction lines of WC were observed. Using six diffraction lines of (001), (100), (110), (111), (211) and (300) among these diffraction lines, lattice constants of an a-axis and a c-axis were determined.
[0043] The average particle size was determined by the Fischer Subsieve Sizer (FSSS) process and the specific surface area due to the BET process was also determined. The content of nitrogen and that of oxygen in the products were measured by using a nitrogen and oxygen analyzing apparatus manufactured by the LECO Co. To eliminate an influence of adsorbed oxygen, the powder was heat-treated in a hydrogen gas atmosphere at 800° C. prior to the measurement. The content of W in the total metal component and the content of free carbon were measured. As is apparent from the results shown in Table 2, all tungsten carbide powders thus obtained are high-purity fine tungsten carbide powders, which contain a metal component having a purity of at least 99.9% by weight, 0.05-0.30% by weight of nitrogen, 0.1-0.6% by weight of oxygen and has an average particle size of 0.8 μm or less and a maximum particle size of 1 μm or less, and some tungsten carbide powder contains traces of free carbon.
[0044] For the purpose of examining the influence of the high-purity fine tungsten carbide powders obtained by the processes 1-15 of the present invention on the strength of the cemented carbide, using the high-purity fine tungsten carbide powders obtained by the processes 2, 5, 8, 11 and 14 among the processes 1-15 of the present invention, commercially available fine tungsten carbide powders having an average particle size and a purity shown in Table 3, the chromium carbide (represented by Cr 3 C 2 ) powder having an average particle size of 1.51 μm, the vanadium carbide (represented by VC) powder having an average particle size of 1.43 μm and the Co powder having an average particle size of 1.35 μm, these raw powders were charged in accordance with the formulation shown in Table 3, wet-milled using an attritor, dried, and then compacted to form a green compact having a size of 10.8 mm×6 mm×30 mm under a pressure of 98 MPa. The resulting green compact was sintered under vacuum of 13.3 Pa under the conditions of a temperature of 1360° C. for one hour, and was then subjected to an HIP (Hot Isostatic Press) in an Ar atmosphere under a pressure of 90 MPa under the conditions of a temperature of 1320° C. for one hour to produce cemented carbides 1-5 of the present invention and comparative cemented carbide 1-5, respectively. The strength was evaluated by measuring the transverse rupture strength of these cemented carbides.
[0045] As is apparent from the results shown in Table 3, all alloys using the high-purity fine tungsten carbide powder obtained by the process of the present invention have a higher strength than that of alloys using commercially available fine tungsten carbide powders.
[0046] As is apparent from the results shown in Table 2 and Table 3, according to the processes 1-15 of the present invention, it is possible to produce high-purity fine tungsten carbide powders which have a high purity of at least 99.9% by weight and also have an average particle size of 0.8 μm or less and a maximum particle size of 1 μm or less. Also the cemented carbides 1-5 of the present invention produced by using these high-purity fine tungsten carbide powders have a small particle size of 0.8 μm or less on average particle size, but have a higher strength than that of comparative cemented carbides 1-5 produced by commercially available fine tungsten carbide powders containing coarse WC particles having a purity of 98% by weight or less or a particle size of 1 μm or less.
TABLE 1 Formulation of slurry (% by weight) AMT APT Ratio of CB powder Concentration Concentration Reduction and to reduction and Purity of Purity of aqueous CB powder carburization carburization Carburization (% by aqueous sloution (% by solution Purity C/W temperature product temperature Class weight) (% by weight) weight) (% by weight) (% by weight) ratio (° C.) (% by weight) (° C.) Process of 1 99.915 35 — — 99.913 3.9 900 0.09 1200 the present 2 99.952 35 — — 99.955 3.5 1000 0.23 1200 invention 3 99.977 35 — — 99.972 3.3 1300 0.42 1600 4 — — 99.911 20 99.915 3.7 1100 0.14 11.00 5 — — 99.956 20 99.954 3.5 1100 0.21 1300 6 — — 99.975 20 99.975 3.2 1100 0.37 1200 7 99.995 20 — — 99.993 4.0 900 0.05 900 8 99.995 35 — — 99.993 3.3 1000 0.17 1100 9 99.995 50 — — 99.993 3.6 1100 0.28 1000 10 99.995 60 — — 99.993 3.2 1300 0.43 1300 11 99.995 70 — — 99.993 3.0 1400 0.48 1400 12 — — 99.996 20 99.997 3.2 1000 0.11 1400 13 — — 99.996 20 99.997 3.2 1200 0.26 1200 14 — — 99.996 20 99.997 3.5 1200 0.32 1300 15 — — 99.996 20 99.997 3.3 1600 0.36 950
[0047]
TABLE 2
Average
Maximum
Specific
W content in entire
Nitrogen
Oxygen
Free carbon
Lattice
particle size
particles size
surface area
metal component
content
content
content
constant (nm)
Class
(μm)
(μm)
(m 2 /g)
(% by weight)
(% by weight)
(% by weight)
(% by weight)
a-axis
c-axis
Process
1
0.35
0.7
3.82
99.913
0.25
0.52
0.04
0.29030
0.28413
of the
2
0.37
0.8
3.47
99.954
0.20
0.49
0.01
0.29035
0.28403
present
3
0.41
1.0
2.93
99.977
0.05
0.18
0.02
0.29060
0.28381
invention
4
0.33
0.8
4.24
99.914
0.20
0.54
0.03
0.29034
0.28406
5
0.38
0.8
3.55
99.955
0.14
0.38
0.00
0.29047
0.28394
6
0.40
0.8
3.01
99.972
0.13
0.21
0.04
0.29047
0.28393
7
0.31
0.7
4.15
99.996
0.25
0.60
0.08
0.29028
0.28412
8
0.36
0.8
3.85
99.994
0.28
0.55
0.04
0.29024
0.28417
9
0.39
0.8
3.50
99.995
0.15
0.36
0.05
0.29044
0.28396
10
0.40
0.9
3.18
99.995
0.12
0.30
0.00
0.29050
0.28392
11
0.55
1.0
2.24
99.994
0.05
0.16
0.00
0.29060
0.28381
12
0.45
0.8
2.89
99.995
0.21
0.57
0.05
0.29036
0.28406
13
0.66
0.8
1.97
99.997
0.17
0.43
0.03
0.29041
0.28398
14
0.75
0.9
1.56
99.995
0.14
0.18
0.01
0.29045
0.28394
15
0.78
1.0
1.42
99.993
0.05
0.10
0.00
0.29059
0.28380
[0048]
TABLE 3
Formulation (% by weight)
WC
Transverse
Average
Maximum
Specific
rupture
W content in entire metal component,
particle size
particle size
surface area
strength
Class
Co
Cr 3 C 2
VC
excluding Co (% by weight)
(μm)
(μm)
(m 2 /g)
Amount
(GPa)
Cemented
1
10
0.8
—
Products of process 2 of the present invention
bals.
4.10
carbide of
2
10
0.5
0.4
Products of process 5 of the present invention
bals.
4.31
the present
3
10
—
0.4
Products of process 8 of the present invention
bals.
4.05
invention
4
10
0.8
—
Products of process 11 of the present invention
bals.
4.19
5
10
0.5
0.4
Products of process 14 of the present invention
bals.
4.27
Comparative
1
10
0.8
—
97.788*
0.37
0.8
3.50
bals.
3.06
cemented
2
10
0.5
0.4
97.754*
0.51
0.9
2.32
bals.
3.22
carbide
3
10
—
0.4
97.660*
0.75
1.5*
1.56
bals.
3.14
4
—
0.8
—
WC-10 wt % Co
0.44
2.9*
3.09
bals.
2.98
composite powder: 99.922
5
—
0.5
0.4
WC-10 wt % Co
0.62
2.1*
1.88
bals.
2.67
composite powder: 99.956
Asterisks (*) denote numerical values outside the scope of the present invention. | A process is provided for producing a fine tungsten carbide powder, which comprises the steps of drying a slurry, which is obtained by mixing an aqueous ammonium tungstate solution with a carbon powder, at low temperature, to form a precursor, mixing a reduction and carburization product, which is obtained by reducing and oxidizing the precursor in an inert gas, with a carbon powder in a proportion required to substantially carburize the entire tungsten component into tungsten carbide (WC), and carburizing the mixture; and a high-performance fine tungsten carbide powder produced by the process, which has an average particle size of 0.8 μm or less and is free of a coarse power having a particle size of more than 1 μm, and which also contains less metal impurities and contains oxygen and nitrogen in a predetermined amount. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority to U.S. Provisional Application Ser. No. 61/794,783, filed on Mar. 15, 2013 the entire disclosure of which is hereby incorporated herein by reference in its entirety.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable
FIELD OF THE INVENTION
The invention lies in the field of keystroke devices. In particular, the invention is in the field of computer or stenographic keyboards and methods and devices for adjusting a height of one or more keys of such keyboards.
BACKGROUND OF THE INVENTION
Various keystroke devices exist in the art. The most prevalent keystroke device is a computer keyboard. The keys of a standard computer keyboard are merely switches electronically indicating only a depressed state. Therefore, no signal is output or indicated by the keyboard when a keyboard is at rest, and a signal corresponding to depressed key(s) is output or indicated only when at least one key is depressed sufficiently far to “set off” the switch of that key or the switches of that set of keys.
A typewriter also has a keyboard, which can be mechanical and/or electronic. Like the computer keyboard, actuation (e.g., depression) of a key is intended to print a character. In electronic typewriters, when a key is actuated sufficiently far, a signal is sent to a processor to have the corresponding key(s) printed on the typing medium (e.g., paper). Mechanical typewriters are similar to electronic typewriters, but with one significant difference. Mechanical typewriters connect the key of the keyboard directly to the hammer containing the corresponding character to be printed on the page. Such a connection typically places the key at the end of a lever connected to a fulcrum and, when the lever is depressed at a proximal end, the distal end of the lever forcibly contacts or causes a hammer to pivot its distal end towards the page. A printing ribbon is disposed between the page and the end of travel of the hammer and a character formed at the end of the hammer is printed on the paper because the raised character presses the printing ribbon against the page.
Another keystroke device can be found on stenographic devices. The most modern stenographic devices are entirely electronic and virtually immediately translate the stenographic key actuations into an accurate written representation of the spoken word. These modern devices are analogous to the electronic typewriters and computer keyboards in that a specific actuation of a key or set of keys will cause a printing or storage of the corresponding character or set of characters.
Prior art stenographic keyboards all have a rear and middle row of ten keys each and a front row of four keys, the latter being closer to the stenographer than the former. In such machines, the keys of the front row correspond to vowels. These keys are, in the prior art, at a level lower (closer to ground) than the two rear rows. Some prior art machines are illustrated in FIGS. 1 to 6 . FIGS. 1 and 2 are views of a stenographic writer manufactured by the Stenograph Corporation and called a Mira. As is clear from FIG. 1 , the vowel keys in the front row are in a different, lower, plane than the keys in the two rear rows. The Mira has the ability to adjust key sensitivity but this adjustment is entirely mechanical, it is also inconvenient. FIG. 3 shows the top of the machine opened, revealing individual key sensitivity adjustment wheels for each of the keys. Thus, in order to make any key adjustment, the top of the machine must be opened. This means that stenographic dictation cannot occur while making a key sensitivity adjustment and also means that the screen of the Mira cannot be viewed while in this adjustment mode. More importantly, after an adjustment has been made, the top must be closed before the user can check to see if the adjustment was adequate. So, the adjustment process must be repeated on a trial-and-error basis for each key, which can be extremely time-consuming. FIGS. 4 and 5 illustrate the depth-of-stroke adjustment wheel and the tension adjustment wheel, respectively. It is noted that the stroke adjustment wheel is hard to reach and cannot be accessed unless the top of the machine is opened. The stroke adjustment wheel is stiff and only permits a small fraction of adjustment as compared to the entire key stroke. Practically, a user cannot type with the machine while an adjustment is being made. Similarly, the tension adjustment wheel in FIG. 5 only allows a small adjustment. Again, the top of the machine must be opened, making it impractical to write with the machine at the same time that an adjustment is being made.
In stenographic machines that are used in countries outside Europe, there are additional keys to the left of the two rear rows. These additional keys are at the same level as the keys in the rear two rows and correspond to different characters that are not needed for English transcription. These keys, in use, can be depressed individually or together. When such machines are used by United States-trained stenographers, these keys are a distraction and/or get in the way of their typing. Accordingly, most machines sold in the United States do not include these keys. In other machines, such users commonly remove these keys.
FIG. 6 illustrates another prior art stenographic machine referred to as the Treal TR, manufactured by Word Technologies. This writer is not adjustable and has plunger-activated keys. There are three holes 60 shown on the left-hand side of FIG. 6 where the extra set of keys were positioned before they were removed. These keys existed in the same plane as the other keys of the three 10-key rear rows. Another prior art writer similar to this machine is called the Gemini, manufactured by the Neutrino Group.
Prior art keyboards were comprised of a set of individual key assemblies 21 . These key assemblies 21 each contained a key pad 22 fixedly connected to a key lever 24 . The key lever 24 was pivotally connected to the writer to enable a keystroke when depressed. A height of each key pad 22 , in the prior art key assemblies 21 , was controlled only by the angle at which the key lever 24 exited the housing 26 of the writer. But, when that angle was adjusted, the upper surface of the key pad 22 was no longer parallel to the remaining key pads 22 . As such, individual key pads 22 in the prior art writers were not adjustable in any way that kept the upper surface parallel to all of the other upper surfaces of the key pads 22 . It would, therefore, be beneficial to provide a way to adjust individual keys so that the upper key pad surface could moved up and down as desired.
As described, prior art stenographic machines have the vowel keys in the lower plane than the other keys. Many reporters, however, find it more comfortable to write with all of the keys in the same plane. Adjustment of the vowel keys has heretofore not been possible. Accordingly, the reporters, themselves, have taken to raise their own vowel keys by adding pads to them. But, with reporters who like to raise their vowel keys, the heights of the keys are not consistently desired. Accordingly, it would be desirable to be able to provide adjustable-height keys having intermediately raised, equally raised, or even extended heights for the vowel keys.
Concurrently, some reporters desire to lower the height of the vowel keys. Prior art writers, however, did not permit this without switching out the entire key lever. It is important to note that to switch out entire such key levers the writers needed to be returned to the manufacturer. Accordingly, it would be desirable to permit the user to lower and raise the height of the keys in a custom way without returning the device to the manufacturer every time adjustment was desired.
Thus, a need exists to overcome the problems with the prior art systems, designs, and processes as discussed above.
SUMMARY OF THE INVENTION
The invention provides devices and methods for adjusting heights of one or more keys of a keyboard that overcome the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type.
As set forth above, prior art stenographic machines sometimes include keys to the left of the 10-key rows. However, these keys are used solely for different characters and are available only for international markets; they are not used for English transcription. The present invention places a single key to the left of each of the two rear rows (these keys are in the second and third rows when start of counting begins at the front row). These two keys, in contrast to any prior art mechanism, have a top surface that is substantially lower than the top surface of the keys in the two rear rows. In particular, the top surfaces of these additional keys are at a level lower than the greatest depression level of any of the keys in the two rear rows. As such, even a full depression of the two left-most keys (corresponding to the “S” phonetic sound) will not permit the wide-pinkied user to accidentally depress either of the two additional left keys. In addition, in the normal writing position, the user will not be able to feel these extra keys, and, therefore, will not misplace his/her hands on the keyboard, which would result in inaccurate fingering.
The systems disclosed use these two additional keys to expand the “vocabulary” of the standard stenographic keyboard, shown, for example, in FIG. 10 . With these additional keys, when any one or both are depressed, three additional keyboards and, therefore, at least 72 additional keys, can be accessed, much like the control, shift, and alt keys on a conventional computer keyboard. If a third key is added in this new column next to the fourth (top) row key, then even more key possibilities become available to the user. These additional keys can be used to represent any character or character set. They can also be used in combination with other standard keys to create additional commands, much like the control, shift, and alt commands of computer keyboards. Additional keys are also necessary for some foreign stenographic theories. Even though the new keys are disposed at a level lower than the lowest depression level of the keys, the user can be trained to use these new keys in a way to make available these foreign stenographic theories. Alternatively, the keys can be configured to rest at two or more different heights depending on the user's choice. In another alternative exemplary embodiment, the shorter keys can be replaced with taller keys that, when installed, have a top surface at a height equal to the top surface height of the other keys, or even higher. In this way, foreign theories of stenography can be accommodated.
Four additional keys can increase the different possible combinations in one stenographic stroke from 2 24 to 2 27 . While 2 24 is already a huge number, the practical number of combinations is much lower; it is limited by the human hand to a maximum of 20 bits out of the maximum of 24 bits. The keys added by the present invention dramatically increase the useful number of keys that can be combined into a single stroke. This increase allows the reporter to write faster because they can create many more practical single-stroke entries.
An additional feature of the present invention does not place the four vowel keys of the front row in a plane lower than the keys of the two rear rows. Raising these keys produces advantages that were not provided previously. For example, stress on the wrist is reduced. Also, raising the keys makes it easier for users with small hands to reach the more distant keys when the vowel keys are simultaneously depressed.
The keystroke device is used particularly with a stenographic or stenotype machine (e.g., for court reporters). In paper stenotype machines, when a court reporter lightly touched a key(s), then the paper would be printed, not with a clear print of the keystroke, but with a light or shadow keystroke. As used herein, the words “keystroke” or a “stenographic keystroke” include any possible actuation of a key device or set of key devices. In other words, the definition includes both recognized key actuations (whether for a single key or a set of more than one key) and any unrecognized, accidental, incorrect, and/or inadvertent actuation of a single key or a set of more than one key.
With the foregoing and other objects in view, there is provided, in accordance with the invention, an adjustable key assembly for a stenographic machine including a key cap having a first removable securing portion and a stenographic keyboard key lever having, a second removable securing portion cooperating with the first removable securing portion to removably hold the key cap thereat over a variety of different positions, a lever connection end having a pivoting connection shaped to attach to the stenographic machine in a pivotable manner and move between a steady-state raised position and a depressed lowered position, and an extension portion extending away from the second removable securing portion and to the lever connection end.
With the objects of the invention in view, there is also provided a stenographic machine including a housing, a stenographic processing unit in the housing, and a stenographic keyboard at the housing and operatively connected to the stenographic processing unit to record stenographic dictation by a user. The stenographic keyboard has a plurality of adjustable key assemblies pivotally connected thereto. Each key assembly has a key cap having a first removable securing portion and a stenographic keyboard key lever having a second removable securing portion cooperating with the first removable securing portion to removably hold the key cap thereat over a variety of different positions, a lever connection end having a pivoting connection attached to the stenographic keyboard to move between a steady-state raised position, and a depressed lowered position, and an extension portion extending away from the second removable securing portion and to the lever connection end.
In accordance with another feature of the invention, the key cap has a top surface and the first removable securing portion and the second removable securing portion are adjustably disposed with respect to one another to place the top surface of the key cap at different vertical heights with respect to ground.
In accordance with a concomitant feature of the invention, the key cap is a set of key caps each having a different sized first removable securing portion to place the key cap, when attached to the key lever, at different positions selected from at least one of a different height and a different length.
Although the invention is illustrated and described herein as embodied in devices and methods for adjusting heights of one or more keys of a keyboard, 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. Additionally, well-known elements of exemplary embodiments of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention.
Additional advantages and other features characteristic of the present invention will be set forth in the detailed description that follows and may be apparent from the detailed description or may be learned by practice of exemplary embodiments of the invention. Still other advantages of the invention may be realized by any of the instrumentalities, methods, or combinations particularly pointed out in the claims.
Other features that are considered as characteristic for the invention are set forth in the appended claims. As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one of ordinary skill in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention. While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views, which are not true to scale, and which, together with the detailed description below, are incorporated in and form part of the specification, serve to illustrate further various embodiments and to explain various principles and advantages all in accordance with the present invention. Advantages of embodiments of the present invention will be apparent from the following detailed description of the exemplary embodiments thereof, which description should be considered in conjunction with the accompanying drawings in which:
FIG. 1 is a fragmentary, perspective view of a prior art stenographic machine from the front;
FIG. 2 is a fragmentary, perspective view of the prior art stenographic machine of FIG. 1 from above the front;
FIG. 3 is a fragmentary, perspective view of an interior portion of the prior art stenographic machine of FIG. 1 from above the front;
FIG. 4 is a fragmentary, perspective view of another interior portion of the prior art stenographic machine of FIG. 1 from above the rear;
FIG. 5 is a fragmentary, enlarged, perspective view of a portion of the prior art stenographic machine of FIG. 3 from above the front;
FIG. 6 is a fragmentary perspective view of another prior art stenographic machine from above the front;
FIG. 7 is a block circuit diagram of an exemplary embodiment of a stenographic system according to the invention;
FIG. 8 is a fragmentary, perspective view of an exemplary embodiment of a stenographic machine according to the invention from a front left side;
FIG. 9 is a diagrammatic illustration of a standard stenographic keyboard;
FIG. 10 is a fragmentary, exploded, perspective view of an exemplary embodiment of a key assembly according to the invention with a key pad having a first height;
FIG. 11 is a perspective view of an exemplary embodiment of a keyboard sub-assembly of a stenographic machine according to the invention from above a front right side;
FIG. 12 is a perspective view of the keyboard sub-assembly of FIG. 11 from below a front left side;
FIG. 13 is a perspective view of the key assembly of FIG. 10 ;
FIG. 14 is a perspective view of an exemplary embodiment of a key assembly according to the invention with a key pad having a second height;
FIG. 15 is a photograph of an exemplary embodiment of a key pad and fasteners according to the embodiment of FIG. 10 ;
FIG. 16 is a fragmentary, exploded, perspective view of the key assembly of FIG. 14 ;
FIG. 17 is a fragmentary, perspective view of another exemplary embodiment of a keyboard sub-assembly of a stenographic machine according to the invention from above a front right side;
FIG. 18 is a fragmentary, perspective view of the keyboard sub-assembly of FIG. 17 from below a front left side;
FIG. 19 is a perspective view of the keyboard sub-assembly of FIG. 17 from above a front;
FIG. 20 is a perspective view of the keyboard sub-assembly of FIG. 17 from below the front;
FIG. 21 is a perspective view of an alternative exemplary embodiment of a key pad, key level, and fastener keyboard sub-assembly with the key pad at a highest setting;
FIG. 22 is a perspective view of sub-assembly of FIG. 21 with the key pad at an intermediate setting;
FIG. 23 is a perspective view of the sub-assembly of FIG. 21 with the key pad at a lowest setting;
FIG. 24 is a perspective view of the sub-assembly of FIG. 21 from the opposite side of the key pad;
FIG. 25 is a side elevational view of a key lever portion of the sub-assembly of FIG. 21 ;
FIG. 26 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from above a front left with key caps for the front and rear control keys and two vowel key caps removed;
FIG. 27 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the left front side with key caps for the four vowel key caps removed;
FIG. 28 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the above a front left with the control keys and the vowel keys in a lowered orientation;
FIG. 29 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the above a left side with the control keys and the vowel keys in a raised orientation;
FIG. 30 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the left front side with the vowel keys in the lowered orientation;
FIG. 31 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the left front side with the vowel keys in an intermediate orientation;
FIG. 32 is a photograph of a perspective view of the keyboard sub-assembly of FIG. 17 from the left front side with the vowel keys in the raised orientation;
FIG. 33 is a photograph of a perspective view of key caps;
FIG. 34 is a photograph of a perspective view of key caps; and
FIG. 35 is a perspective view of an alternative exemplary embodiment of a modular key pad system.
DETAILED DESCRIPTION OF THE INVENTION
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting; but rather, to provide an understandable description of the invention. While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures, in which like reference numerals are carried forward.
Alternate embodiments may be devised without departing from the spirit or the scope of the invention. Additionally, well-known elements of exemplary embodiments of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention.
Before the present invention is disclosed and described, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. The terms “a” or “an”, as used herein, are defined as one or more than one. The term “plurality,” as used herein, is defined as two or more than two. The term “another,” as used herein, is defined as at least a second or more. The terms “including” and/or “having,” as used herein, are defined as comprising (i.e., open language). The term “coupled,” as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.
Relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.
As used herein, the term “about” or “approximately” applies to all numeric values, whether or not explicitly indicated. These terms generally refer to a range of numbers that one of skill in the art would consider equivalent to the recited values (i.e., having the same function or result). In many instances these terms may include numbers that are rounded to the nearest significant figure.
It will be appreciated that embodiments of the invention described herein may be comprised of one or more conventional processors and unique stored program instructions that control the one or more processors to implement, in conjunction with certain non-processor circuits and other elements, some, most, or all of the functions of the powered injector devices described herein. The non-processor circuits may include, but are not limited to, signal drivers, clock circuits, power source circuits, and user input and output elements. Alternatively, some or all functions could be implemented by a state machine that has no stored program instructions, or in one or more application specific integrated circuits (ASICs) or field-programmable gate arrays (FPGA), in which each function or some combinations of certain of the functions are implemented as custom logic. Of course, a combination of these approaches could also be used. Thus, methods and means for these functions have been described herein.
The terms “program,” “software,” “software application,” and the like as used herein, are defined as a sequence of instructions designed for execution on a computer system. A “program,” “software,” “computer program,” or “software application” may include a subroutine, a function, a procedure, an object method, an object implementation, an executable application, an applet, a servlet, a source code, an object code, a shared library/dynamic load library and/or other sequence of instructions designed for execution on a computer system.
Herein various embodiments of the present invention are described. In many of the different embodiments, features are similar. Therefore, to avoid redundancy, repetitive description of these similar features may not be made in some circumstances. It shall be understood, however, that description of a first-appearing feature applies to the later described similar feature and each respective description, therefore, is to be incorporated therein without such repetition.
Described now are exemplary embodiments of the present invention. Referring now to the figures of the drawings in detail and first, particularly to FIG. 7 thereof, there is shown a block circuit diagram of a stenographic device according to the invention. The stenographic machine 1 has a keyboard 10 having plurality of keystroke devices, which are connected to an on-board proceeding unit including a microprocessor 2 . A memory 3 (e.g., RAM, ROM, hard drive, removable memory) is connected to the microprocessor 2 for storing data and supplying stored data to the microprocessor 2 and for storing and executing software. A display 4 is connected to the microprocessor 2 for displaying stenographic and/or translated data and for displaying the shadows determined/detected by the microprocessor 2 . The microprocessor 2 controls all electronic operations including receiving stenographic data and shadow data, storing all data, and displaying all desired processes, which processes can include the stenographic and/or level data itself, indications that data is being stored, indications that data is being translated, translated stenographic output, and in many others.
Depending upon the configuration of the stenographic device, a translator 5 can be on-board the device and, therefore, it is directly connected to the microprocessor 2 for translating stored or incoming (real-time) stenographic data. Thus, input electronics for the keystroke device can be directly connected to the same processor 2 that controls the translation program, and the functions of input, shadow determination, translation, and correction/editing can be performed on a single unit 1 .
If the translator is not on board the stenographer's device 1 , then the device 1 can be connected to an external stenographic translator 6 , in which case the translator 6 is separate from the stenographic device 1 and information stored in the memory 3 is relayed 7 either by transfer through an intermediate media (e.g., floppy disk, CD/DVD, micro-drive, flash drive), in which case the device will have a floppy drive, CD/DVD drive, USB port, Firewire port, etc., or wirelessly through some kind of communication data link (e.g., a Bluetooth, ISDN, Internet, or other wireless data link), in which case the device will have an on-board transceiver 8 or other communications device.
In either case, the translator 5 , 6 translates the stenographic data to the respective language (e.g., English). When the device 1 is associated directly with a translation system, translation occurs quickly so that the stenographer can view his/her stenographic keystrokes in almost real-time and in relatively understandable English (dependent upon the quality of the word/translation processor). The memory 3 will store the translation locally 3 , 11 and/or externally 7 , 9 .
FIG. 7 further illustrates the stenographic device 1 and an embodiment 9 for connecting the device to an external stenographic translator 6 . In the example of FIG. 7 , the translator 6 is connected to the Internet and is housed at a location different from the stenographer's location. In such a networked configuration, the transceiver 8 can utilize a bi-directional data channel to transmit the un-translated stenographic data to the external translating computer 6 (represented by the dashed arrows), whether in real time or delayed. The translating computer 6 can, then, translate the stenographic data and transmit a translated data stream back to the device immediately or at a later time and to any other device that can be connected (directly or wirelessly) to the translating computer (also represented by the dashed arrows). Thus, the stenographer can have almost real-time analysis even without having an on-board translator.
One example of such a system 9 provides the stenographic device 1 with a connection (e.g., a direct or wireless transceiver 8 ) to the Internet and the external translating computer 6 with a connection (direct or wireless) also to the Internet. Thus, commonly available Internet connection devices available at the location where the stenographer is taking data can be used to facilitate quick and inexpensive translation of stenographic data without having to store the translation software on the stenographer's machine 1 .
When the device 1 has an integrated word processing system, then the functions of dictation, translation, and editing of the translation can be performed by the stenographer on a single machine.
The device 1 can also include a multi-media recorder 11 that can store, in an on-board memory or the memory 3 , digital video images and/or audio data. By recording the audio and/or video of the subject(s) of the stenographer on the device, it becomes possible to associate a portion of a multi-media file with a stenographic stroke. Such recording and coordination of stenographic and video and/or audio data allows the stenographer to playback images of and/or sounds from the subject to assist in the accurate translation of the stenographic keystrokes. Such multi-media data can also be transmitted to other computers and/or locations through network connections, for example, over the Internet, by wireless connections, such as Bluetooth, by direct connections, such as RS-232, universal serial bus, IRDA, Firewire, or by any other available data communications measures to assist the stenographer in accurate translation of the stenographic data.
FIG. 8 illustrates a side view of a first embodiment of a stenographic writer 1 described herein. The writer 1 has a housing 12 and a stenographic keyboard 10 . The keys shown in FIG. 8 are illustrated in their normal rest state or undepressed state. A conventional stenographic keyboard has four rows, the front row 16 having four keys corresponding to vowels and two rear rows 20 , 30 of ten keys each as shown in FIG. 9 . The two left-most keys correspond to the same letter and, therefore, are shown in FIG. 9 as a single key. On traditional machines, an “S” is produced whether the reporter presses the key in the second row or the third row because these keys are tied together—they are essentially one key. By adding at least one additional key in the present invention, the reporter has the option of defining every other key differently, if depression of that key changes the state of one or more other keys. The benefits arise by splitting the “S” key into two keys at the far left-hand side of the keyboard 10 . See, e.g., FIG. 8 . The inventive keyboard also employs the same separation with the asterisk key, located at the middle of the keyboard 10 . On traditional machines, although it might appear that there are two keys in the middle, they are, in fact, tied together and generate the same code.
The fourth row 40 of keys can take any form but is, commonly, a single key having a width equal to the ten adjacent keys of the rear rows 20 , 30 . This single key 40 can, in another exemplary embodiment, be a set of keys as shown in FIG. 8 , each having a separate corresponding definition. As used herein with respect to the keys of the keyboard 10 , “rear” is a position that is further away from the user than keys in the “front” of the keyboard 10 .
With respect to FIGS. 8 and 9 , the four vowel keys are shown in a front or first row 16 and, in the exemplary embodiment of FIG. 8 , they are positioned in a conventional lower orientation or position. Here, “lower” is used as a relative word to compare the top surface of the keys in the first row 16 to the top surface of the keys in the second, third, and fourth rows 20 , 30 , 40 , the top surfaces of which are all at the same height.
The keyboard 10 described herein includes a novel new side column 50 of two additional keys 52 and 54 , which are referred to herein as control keys.
The keys in the second, third, and fourth rows 20 , 30 , 40 can each be depressed to a lower-most position. The top surface of these keys, when in this lower-most position, is higher than the top surface of the control keys 52 , 54 when the control keys 52 , 54 are not depressed. As such, when the left-most keys in either of the second, third, and fourth rows 20 , 30 , 40 are depressed, a finger that is on the left edge will not be able to depress either of the two control keys 52 , 54 . In other words, the user must make a conscious decision to depress either or both of the control 52 , 54 keys.
The control keys 52 , 54 have various uses in the described writer 1 . One exemplary use expands the “vocabulary” of the stenographic keyboard defined by the first to fourth rows 16 , 20 , 30 , 40 . With the control keys 52 , 54 , when any one or both are depressed, three additional keyboards can be accessed. Therefore, using the programming of the control system of the writer 1 to assign a different definition to each key when either the first control key 52 , the second control key 54 , or both control keys 52 , 54 are depressed adds 72 additional keys to the twenty-four key original keyboard.
The control keys 52 , 54 can be configured as press-on/press-off keys so that, when pressed once, they turn on and, upon a second press, they turn off. This feature is beneficial, for example, if non-activation of the keys 52 , 54 is an English keyboard where activation of one of the two control keys 52 , 54 turns the keyboard into a Spanish keyboard. The press-on/press-off function can be either mechanical or electronic. More specifically, once pressed, the key can stay depressed until it is pressed a second time, where it will physically return to its original starting height. Alternatively, in the electronic embodiment, once the key is depressed once, a “flag,” or bit is set, indicating the transition from a rest state to the depressed state. In this electronic exemplary embodiment, although the key physically returns to the starting rest state, the status of the key is “depressed.” To return the key to its original state, the key is transitioned again from the rest state, to the depressed state, and back to the rest state.
The novel keyboard 10 is comprised of a set of individual key assemblies 100 shown, for example, in FIGS. 8 , 10 , 13 and 14 . Like prior art key assemblies 21 , the key assemblies 100 of the invention shown in FIG. 8 each contain a key pad 82 fixedly connected to a key lever 84 with the key lever 84 being pivotally connected to the writer 1 to enable a keystroke when depressed. This is where the similarity ends. A height of each key pad 82 , however, is not controlled only by the angle at which the key lever 84 exited the housing 12 of the writer 1 . Rather, each individual key pad 82 is adjustable in a way that keeps the upper surface parallel to all of the other upper surfaces of the key pads 82 .
FIG. 10 illustrates a first exemplary embodiment of a single keystroke assembly 100 to be used in the inventive keyboard 10 , e.g., a keyboard of a stenographic writer 1 . The keystroke assembly 100 has a key lever 102 and a key pad 104 having a contact surface 106 at which a user imparts the force for activating the keystroke assembly 100 . The key pad 104 is connected to a proximal end 103 of the key lever 102 . The key lever 102 is connected movably to a key-retaining device 110 (see FIGS. 11 and 12 ) at a pivot point 120 . The key lever 102 defines a pivot area 130 disposed between a distal portion 132 of the key lever 102 and the proximal end 103 of the key lever 102 . The key lever 102 has a non-illustrated bias device (e.g., a spring) imparting a force upon the key lever 102 to keep the contact surface 106 raised, i.e., in a non-actuated position. To impart a raising force to the key lever 102 , the spring is oriented so that the force imparted on the key lever 102 rotates the proximal end 103 counter-clockwise with respect to FIGS. 10 and 12 to 14 about the pivot point 120 . The configuration of the bias device can take any form and the direction of force imparted by biasing spring can be in any direction so long as the contact surface 106 is raised when not activated and biases the key back to the raised position after being actuated. (The described configuration, of course, assumes that the keystroke assembly 100 is to be actuated by a lowering movement. Force in the opposite direction applies if the keystroke assembly 100 is to be lifted by a user.)
Height adjustability of each key pad 104 is accomplished in an exemplary embodiment shown in FIGS. 10 , 11 , 12 , 13 , and 15 . Here, instead of having the key pad 104 fixed to the key lever 102 (e.g., integrally), a removable connection 108 is provided. This removable connection 108 can take any form. In the exemplary embodiment shown, the proximal end 103 of the key lever 102 forms a tab that is inserted into a groove of a hollow boss 105 projecting downward from the lower surface of the key pad 104 . Fasteners 109 (here in the exemplary form of bolts) removably connect the key pad 104 to the key lever 102 . It is noted that the height of the exemplary boss 105 in FIGS. 10 , 11 , 12 , and 13 is slightly larger than the head of the fastener 109 and, therefore, provides a first “low” key pad height. In contrast thereto, the boss 145 shown projecting from the key pads 144 illustrated in FIGS. 14 and 16 to 20 is much longer and, therefore, provides a second “high” key pad height. These two exemplary embodiments of the key pads illustrate how easily a modular set of key pads can be created and used to customize each and every keystroke assembly 100 of the inventive stenographic keyboard. The exemplary embodiments of the key pad attachments shown are not the only possibilities for attaching the key pad 104 , 144 to the key lever 102 . Further, the key assemblies 100 are envisioned not only for use on the vowel keys 16 , but for all keys, 20 , 30 , 40 on the stenographic keyboard 10 .
FIGS. 26 to 31 illustrate various configurations of the interchangeable key caps 104 , 144 , 2100 in the installed and removed states. FIG. 26 shows the key caps for the front and rear control keys 54 , 52 , respectively, removed as well as the “A” and “O” key caps removed. The “E” and “U” key caps are shown in the lowered orientation. FIG. 27 shows all of the vowel key caps removed. FIG. 28 shows all key caps installed in a lowered orientation and with the front and rear control keys 54 , 52 , respectively, in the lowered orientation. FIG. 29 , in contrast, shows the front and rear control keys 54 , 52 , respectively, in a raised orientation even with the keys in the respective consonant rows 20 , 30 . Here, too, the vowel key caps are shown in the raised orientation. FIGS. 30 to 32 illustrate the difference in height of the lowered ( FIG. 30 ), the intermediate ( FIG. 31 ), and the raised ( FIG. 32 ) orientations for the vowel key caps.
A standard fourth row bar 40 extends from the “S” key on the left to the “D” key on the right as shown in FIG. 9 . It is noted, however, that some embodiments described herein include the additional control keys, such as those shown in FIGS. 12 , 17 to 20 , 26 , 28 , and 29 . With the control keys, the standard fourth row bar 40 would not extend all the way to the control keys. The configuration shown in FIGS. 28 and 29 , however, show the inventive fourth row bar 40 extending leftward so that it lies behind the third row control key just at it lies behind the other third row consonant keys. By extending the fourth row bar 40 , the bar 40 can be pressed in conjunction with the control key that is immediately in front of it, using the same finger.
As can be seen from the key arms in FIGS. 26 and 27 , they are parallel to one another yet the keys on the two rows 20 , 30 are aligned with one another from front to back. This is accomplished by connecting the key caps to the key arms at respective right or left sides of the bottom surfaces. The mirror image connection bosses are illustrated best in FIGS. 32 and 33 , showing key caps from each of the two consonant rows 20 , 30 and the vowel row 16 .
In the exemplary embodiments illustrated, the fasteners 109 pass through holes in the key levers 102 , 142 . If the holes were slots, then the fasteners 109 could be loosened so that the user could individually adjust the key pads 104 , 144 to any desired height. Also, if the slots were circular segments having a centerpoint at the opposing connection (e.g., screw), then the key pads 104 , 144 could be tilted, if desired by the stenographer, by loosening one screw and pivoting the key pad 104 , 144 about the other screw. Also, a plurality of screw holes 107 , either individual or pairs, can be added to those shown to permit different heights for the key pads 104 , 144 as desired. One exemplary embodiment of the multiple screw holes 107 is depicted in FIGS. 21 to 25 , where multiple rows of holes 1107 exist on the key cap 2100 and one row of holes 1107 exists on the key lever 2110 . In an alternative non-illustrated configuration, the multiple rows of holes 1107 can exist on the key lever 2110 and one row of holes 1107 can exist on the key cap 2100 . As a further alternative, multiple rows can exist on both. Two holes are not required in these embodiments, they are only examples. It is found, however, that multiple securing points provide greater stability than just a single securing point, but one is envisioned as well.
As an alternative to the key lever 102 , 142 having a bend (e.g., an approximately 90-degree bend as shown in FIGS. 10 to 25 ), it is also possible to configure the key pad 104 , 144 to have the bend itself and the tab would be at a distal end of a straight key lever 102 , 142 .
As discussed above, the writer 1 has extra keys, for example, the two control keys on the left-hand side of the keyboard 10 . The inventive keys here are envisioned to apply the height adjustable embodiments to this keyboard 10 as well so the reporter can adjust each key as desired.
In addition to providing the key pads mentioned herein with adjustable heights, the key levers can be made adjustable to provide the user with adjustable key lever lengths. Also, to provide such longer key levers without having to replace the lever, the 90-degree bend can be part of the key pad 104 , 144 with the holes 107 moved towards the distal portion 132 of the key lever 102 (as shown with the dashed line 111 in FIG. 10 ). Then, the adjustable and/or removable key pad/lever portions (not illustrated) could be easily changed by the user for custom key lever lengths. For example, one user might prefer a longer (closer to the reporter) vowel key in an embodiment where the vowel keys are raised to have an upper surface at the same level as the other keys. This occurs when the user does not want to stretch his/her thumbs far, which does not occur if the vowel keys are in the same plane. Reporters with large hands have indicated, for example, that they have to “scrunch up” their thumbs to keep them from going past the end of raised vowel keys, which happens when their thumbs are extended.
Another non-illustrated way to raise and lower the key caps is with a ratcheting or click-stop connection that allows the user to move the key cap up and down after raising or pressing in a tab that unlocks the ratchet.
Yet another way to provide key caps that can be raised and lowered is with a modular system 3500 of keys caps 3510 shown, for example, in FIG. 35 . Only the key pad (e.g., 82 ) of a standard key lever that connects to a stenographic machine is illustrated in FIG. 35 . The modular keycap 3500 is actually a snap-on attachment to an end platform 3510 formed by the key pad 82 . These snap-on keycaps 3500 can be made with varying heights H, only one of which is shown in FIG. 35 . In this exemplary configuration, the keycap 3500 simply snaps onto the platform 3510 on top of a key arm. Because the spacing between the keys of a stenographic keyboard is small, the keycaps 3500 snap on from the side rather than snapping on from the front of the key. These keycaps 3500 , for example, can be used easily on the four vowel keys 16 at the bottom of the keyboard and on the extra keys on the far left of the inventive keyboard. Because there is no adjacent key on one side of each of those keys, the keycap 3500 does not create any interference. These keycaps 3500 both snap on from the left and snap on from the right of a key platform 3510 .
With this exemplary embodiment, the keycaps 3500 are also a little longer than the original keycaps. This can be a benefit for the vowel keys 16 on the front of the stenographic machine because, when these keys 16 are raised from their lower orientation, the reach to them with the thumbs of the user is shortened. It is, therefore, possible for reporters to “overshoot” standard-length vowel keys in the raised orientation, which does not occur if they are lengthened somewhat, for example, by the keycaps 3500 .
It is noted that various individual features of the inventive processes and systems may be described only in one exemplary embodiment herein. The particular choice for description herein with regard to a single exemplary embodiment is not to be taken as a limitation that the particular feature is only applicable to the embodiment in which it is described. All features described herein are equally applicable to, additive, or interchangeable with any or all of the other exemplary embodiments described herein and in any combination or grouping or arrangement. In particular, use of a single reference numeral herein to illustrate, define, or describe a particular feature does not mean that the feature cannot be associated or equated to another feature in another drawing figure or description. Further, where two or more reference numerals are used in the figures or in the drawings, this should not be construed as being limited to only those embodiments or features, they are equally applicable to similar features or not a reference numeral is used or another reference numeral is omitted.
The phrase “at least one of A and B” is used herein and/or in the following claims, where A and B are variables indicating a particular object or attribute. When used, this phrase is intended to and is hereby defined as a choice of A or B or both A and B, which is similar to the phrase “and/or”. Where more than two variables are present in such a phrase, this phrase is hereby defined as including only one of the variables, any one of the variables, any combination of any of the variables, and all of the variables.
The foregoing description and accompanying drawings illustrate the principles, exemplary embodiments, and modes of operation of the invention. However, the invention should not be construed as being limited to the particular embodiments discussed above. Additional variations of the embodiments discussed above will be appreciated by those skilled in the art and the above-described embodiments should be regarded as illustrative rather than restrictive. Accordingly, it should be appreciated that variations to those embodiments can be made by those skilled in the art without departing from the scope of the invention as defined by the following claims. | A stenographic machine including a housing, a stenographic processing unit in the housing, and a stenographic keyboard at the housing and operatively connected to the stenographic processing unit to record stenographic dictation by a user. The stenographic keyboard has a plurality of adjustable key assemblies pivotally connected thereto. Each key assembly has a key cap having a first removable securing portion and a stenographic keyboard key lever having a second removable securing portion cooperating with the first removable securing portion to removably hold the key cap thereat over a variety of different positions, a lever connection end having a pivoting connection attached to the stenographic keyboard to move between a steady-state raised position and a depressed lowered position, and an extension portion extending away from the second removable securing portion and to the lever connection end. | 1 |
RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/950,465, which was filed Mar. 10, 2014, the entire disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
The presently disclosed subject matter relates to installing fencing. More particularly, the present invention relates to a fence installation jig.
BACKGROUND OF THE INVENTION
There are many home improvement projects a home owner can undertake to update and beautify their homes. One (1) of the most popular and useful is fencing. A fence can enhances the aesthetic beauty of a home and its landscaping, serve as a boundary for children and pets, act as a deterrent for trespassers, and help maintain good relationships with neighbors.
Modern fencing takes many forms. Picket fences, chain link fences, wood fences, and vinyl fences are all widely available. Modern fencing provides home owners with a variety of styles, quality construction, and years of services with little or no maintenance. However, actually constructing a fence tends to be time consuming and is very labor intensive. For example, vinyl fences are usually constructed of vinyl fence panels that are attacked to fence posts. In the prior art constructing a vinyl fence required one to carefully measure and then re-measure a cut before actually making that cut. A mistake was costly both in time and materials. Additionally, in the prior art it was often difficult to determine accurate locations where vinyl fence connectors needed to be located when attaching each panel. Wood privacy fences had similar problems.
In view of the foregoing there exists a need for a device that makes construction of vinyl and privacy fencing easier, faster, and simpler.
SUMMARY OF THE INVENTION
The principles of the present invention provide for a jig that makes construction of privacy fencing such as those made of vinyl and wood easier, faster, and simpler.
A fence jig that is in accord with the present invention includes an elongated board having a planar fence face and a planar post face opposite the fence face. A rip edge extends between the fence face and the post face and an outer edge is located opposite the rip edge. The board further includes a top edge and a bottom edge. The fence jig also includes a post guide that attached to the board top edge and which perpendicularly projects out the said post face to form an under face. A first flange is attached to the fence face. The first flange has a first flange board face in contact with the fence face, a first flange fence face opposite the first flange board face, a top edge above the first flange board face and the first flange fence face, a first flange rip edge on the left of the first flange board face; a first bracket upper edge opposite the top edge, and the thickness of a stringer of a fence being constructed.
The fence jig also includes a second flange attached to the fence face, the second flange having a second flange board face in contact with the fence face, a second flange fence face opposite the second flange board face, a first bracket lower edge above the second flange board face and the second flange fence face, a second flange rip edge to the left of the second flange board face; a second bracket upper edge opposite the first bracket lower edge, and the thickness of a stringer of a fence being constructed.
The Fence Jig also includes a third flange attached to the fence face. The third flange having a third flange board face in contact with the fence face, a third flange fence face opposite the third flange board face, a second bracket lower edge above the third flange board face and the third flange fence face, a third flange rip edge to the left of the third flange board face; and a second flange bottom edge opposite the second bracket lower edge, and the thickness of a stringer of a fence being constructed.
In practice, the post guide is placed on top of a fence post with the post face in contact with that fence post. Then the first bracket upper edge is located where the top of a “U”-shaped bracket should go.
In addition, the fence jig can include a first spacer that attached to the post face and to the under face to form a first reference edge, a second spacer attached to the post face to form second reference edge, and a third spacer attached to the post face to form a third reference edge such that the first reference edge, the second reference edge, and the third reference edge are coplanar.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings in which like elements are identified with like symbols and in which:
FIG. 1 is a front elevation view of a Fence Jig 10 that is in accord with the preferred embodiment of the present invention;
FIG. 2 is a side elevation view of the fence jig 10 ;
FIG. 3 is a rear elevation view of the fence jig 10 ;
FIG. 4 is an isometric view of the fence jig 10 ;
FIG. 5 a is an isometric view of the fence jig 10 on a fence post 100 as used for locating a first “U”-shaped bracket 125 and a second “U”-shaped bracket 130 ;
FIG. 5 b is an isometric view from an opposite perspective of FIG. 5 a of a fence jig 10 on a fence post 100 ;
FIG. 6 is an isometric view of a fence jig 10 on a fence panel 105 as used for preparing for a width trimming cut; and,
FIG. 7 is an isometric view of the fence jig 10 on a fence panel 105 as used for preparing a height trimming cut.
DESCRIPTIVE KEY
10 fence jig
16 threaded fastener
20 board
22 post face
24 fence face
26 outer edge
28 rip edge
29 bottom edge
30 post guide
32 top face
34 under face
40 first flange
42 first flange board face
43 first flange fence face
44 top edge
46 first bracket upper edge
48 first flange rip edge
50 second flange
52 second flange board face
53 second flange fence face
54 first bracket lower edge
56 second bracket upper edge
58 second flange rip edge
60 third flange
62 third flange board face
63 third flange fence face
66 second bracket lower edge
68 third flange rip edge
69 third flange bottom edge
70 first spacer
76 first reference edge
80 second spacer
86 second reference edge
90 third spacer
96 third reference edge
100 post
105 fence panel
110 stringer
115 picket
120 panel fastener
125 first “U”-shaped bracket
130 second “U”-shaped bracket
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The preferred embodiment of the present invention is depicted within FIGS. 1-7 . However, the invention is not limited to what is specifically illustrated and described. A person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention. Any such work around also falls with the scope of this invention.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. In addition, unless otherwise denoted all directional signals such as up, down, left, right, inside, outside are taken relative to the illustration shown in FIG. 1 .
Referring now to FIGS. 1 and 5 a - 7 , the present invention describes a fence jig 10 which aids in the installation of a privacy fence. That fence is fabricated from vinyl (or wood) fence panels 105 which are guided into place by the fence jig 10 when attaching a first “U”-shaped bracket 125 and a similar second “U”-shaped bracket 130 to a previously erected fence post 100 . The fence jig 10 also acts as a guide when adjusting the width and/or height of the fence panels 105 .
Referring now specifically to FIGS. 5 a and 5 b , each fence panel 105 is usually provided as a pre-fabricated structure that typically measures sixty eight inches (68 in.) in length and sixty eight inches (68 in.) in height. Each fence panel 105 is composed of twelve ( 12 ) individual pickets 115 that are attached together on both sides by two (2) stringers 110 . To install the fence panel 105 the stringers 110 are attached to pre-installed fence posts 100 using panel fasteners 120 that are inserted into an upper first “U”-shaped bracket 125 and into a lower second “U”-shaped bracket 130 . The fence posts 100 are preferably seventy two inches (72 in.) in height and will usually have some portion buried underground as required to meet applicable local building codes.
FIG. 1 presents a front elevation view, FIG. 2 presents a side elevation view, FIG. 3 presents a rear elevation view, and FIG. 4 presents an isometric view of the fence jig 10 . The fence jig 10 includes a board 20 and a top post guide 30 . The board 20 is the central part of the fence jig 10 to which other pieces are attached. The board 20 and the post guide 30 are preferably composed of wood or vinyl. Other materials, such as composite materials, other thermoplastics, and metal, may also be used. The board 20 is both flat and straight with straight edges. The board 20 is typically about seventy two inches (72 in.) long to correspond to the height of a fence post 100 . The face showing in FIG. 1 is designated as the post face 22 . The post face 22 is the face which is placed against a fence post 100 when the fence jig 10 is being used to attach fence panels 120 . The face opposite the post face 22 is the fence face 24 ; specifically reference FIG. 3 . The long edge on the left side of the board 20 as seen in FIG. 1 is the rip edge 28 . The rip edge 28 acts as a guide for a power saw that is used to make cuts to a fence panel 105 when making width adjustments to fit the fence panel 105 to a fence post 100 . The long edge opposite the outside edge 26 is the rip edge 28 . The short edge at a bottom of the board 20 is the bottom edge 29 .
The post guide 30 is a square piece that projects over the front of the board 20 (best shown in FIG. 5 a ). The post guide 30 is attached to the top of the board 20 , preferably by adhesive and at least one (1) threaded fastener 16 . The face of the post guide 30 in contact with the board 20 is the under face 34 while the upper face is the top face 32 .
Referring again primarily to FIGS. 1-4 , attached to the fence face 24 are a first flange 40 , a second flange 50 , and a third flange 60 . Attachment is preferably made using adhesive and threaded fasteners 16 ; see FIG. 3 . The first flange 40 , the second flange 50 , and the third flange 60 are preferably made of the same material as the board 20 . In any event they have the same thickness as the stringers 110 . The surface of the first flange 40 in direct contact with the fence face 24 is the first flange board face 42 . The opposite surface of the first flange 40 is the first flange fence face 43 . In use the first flange fence face 43 is placed against a fence panel 105 when using the fence jig 10 . The narrow edge of the first flange 40 closest to the post guide 30 is the top edge 44 . The narrow edge of the first flange 40 opposite that is the first bracket upper edge 46 . The first bracket upper edge 46 contacts the top of the first “U”-shaped bracket 125 when fastening a first “U”-shaped bracket 125 to a fence post 100 . The left side long edge of the first flange 40 is the first flange rip edge 48 (see FIG. 2 ). This first flange rip edge 48 , along with corresponding edges on the second flange 50 and the third flange 60 , acts as a guide for a power saw when making height adjustment cuts to fence panels 105 to make them properly fit between fence posts 100 . The first flange 40 is attached to the board 20 at a location which places the first “U”-shaped bracket 125 at the correct height on the fence post 100 to engage the top stringers 110 of fence panels 105 when the post guide 20 is on top of a fence post 100 and the first bracket upper edge 46 is adjacent the upper surface of a first “U”-shaped bracket 125 .
The second flange 50 has similar faces and long edges as the first flange 40 . Specifically, a second flange board face 52 , a second flange fence face 53 , and a second flange rip edge 58 . The third flange 60 is also configured similarly with a third flange board face 62 , a third flange fence face 63 , and a third flange rip edge 68 . The upper narrow edge of the second flange 50 is the first bracket lower edge 54 . The narrow edge of the second flange 50 is the second bracket upper edge 56 . The length of the second flange 50 corresponds to the distance between the upper stringer 110 and the lower stringer 110 on the fence panel 105 . The upper narrow edge of the third flange 60 is the second bracket lower edge 66 . The edge opposite the second bracket lower edge 66 is the third flange bottom edge 69 . The third flange 60 is attached to the bottom of the board 20 . The length of the third flange 60 corresponds to the distance between a lower stringer 110 on a fence panel 105 and grade level.
Disposed on the post face 22 are a first spacer 70 , a second spacer 80 , and a third spacer 90 . Each of the spacers 70 , 80 , 90 is about three inches (3 in.) high and two inches (2 in.) wide. The first spacer 70 , the second spacer 80 , and the third spacer 90 are attached to the board 20 , preferably by adhesive and threaded fasteners 16 . The upper surface of the first spacer 70 is attached to the under face 34 of the post guide 30 . The left edge of the first spacer 70 is a first reference edge 76 . The second spacer 80 is attached to the board 20 approximately two inches (2 in.) below the first spacer 70 . The left edge of the second spacer 80 is a second reference edge 86 . The third spacer 90 is attached to the board 20 approximately forty-one inches (41 in.) below the second spacer 80 . The left edge of the third spacer 90 is a third reference edge 96 . The first reference edge 76 , the second reference edge 86 , and the third reference edge 96 are coplanar and are used to align the rip edge 28 of the board 20 with the correct lateral location for a first “U”-shaped bracket 125 and a second “U”-shaped bracket 130 when the under face 34 of the post guide 30 is placed on top of a fence post 100 and the reference edges 76 , 86 , and 96 are in contact with fence post 100 .
Refer now to FIG. 5 a for an isometric view of the fence jig 10 on a fence post 100 , to FIG. 5 b for an isometric view of the fence jig 10 from another perspective, and to FIG. 3 . In FIG. 5 a the fence jig 10 is shown in use locating a first “U”-shaped bracket 125 at the correct location. The top guide 30 is placed on the top of the fence post 100 with the first spacer 70 , second spacer 80 , and the third spacer 90 flush against the fence post 100 . When so arranged the first “U”-shaped bracket 125 is set in place by locating it on the inner face of the rip edge 28 between the first bracket upper edge 46 and the first bracket lower edge 54 . The first “U”-shaped bracket 125 is then attached to the fence post 100 using one or more fasteners 120 . A second “U”-shaped bracket 130 is then located on the fence post 100 by placing the second “U”-shaped bracket's “U”-shape against the inner face of the rip edge 28 between the second bracket upper edge 56 and the second bracket lower edge 66 . The second “U”-shaped bracket 130 is then attached to the fence post 100 using one or more fasteners 120 . Another first “U”-shaped bracket 125 and another second “U”-shaped bracket 130 can be located and attached to the opposite side of the post by moving the fence jig 10 to the opposite side and then repeating the process.
Refer now to FIG. 6 for an isometric view of the fence jig 10 used on a fence panel 105 and to FIG. 4 for details of the fence jig 10 . During the installation of the fence the standard length of the fence panel 105 may exceed the distance between adjacent fence posts 100 . In that case the fence panel 105 needs to be cut to fit. The fence jig 10 can assist this cutting. To do so the fence panel 105 is positioned on a stable horizontal work surface with the excess length overhanging the supports. The fence jig 10 is placed on the fence panel 105 with the fence face 24 in contact with the fence panel 105 . The upper stringer 110 is between the first flange 40 and the second flange 50 and the lower stringer 110 is located between the second flange 50 and the third flange 60 . The first flange board face 42 , the second flange board face 52 , and the third flange board face 62 are in the same plane as the exposed faces of the stringers 110 with the first flange rip edge 48 , second flange rip edge 58 and third flange rip edge 68 aligned with the desired cut line on the fence panel 105 . A saw is then run along the fence panel 105 using the rip edge 28 as a guide. The result is a clean, straight cut across the length of the fence panel 105 . In practice the fence jig 10 may be clamped to the fence panel 105 to keep the fence jig 10 in place.
Refer now to FIG. 7 for an isometric view of the fence jig 10 on a fence panel 105 being used to adjust the height of a fence panel 105 . In some applications the height of a fence panel 105 may need to be adjusted by cutting. The fence jig 10 assists this cutting. To do so the fence panel 105 is positioned on a stable horizontal work surface with the excess height overhanging the supports. The fence jig 10 is placed longitudinally on the fence panel 105 with the fence face 24 in contact with the fence panel 105 . The fence jig 10 is then aligned with the desired cut line to allow the saw to cut the fence panel by being moved along the first flange rip edge 48 , the second flange rip edge 58 , and the third flange rip edge 68 . In practice the fence jig 10 should be clamped to the fence panel 105 during cutting.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. | A fence jig is provided for assisting construction of privacy fences. The fence jig includes an elongated board that is the length of a fence post. Attached to that board is a post guide that fits on the fence post. First, second, and third flanges are attached to the board with dimensions that place gaps between the flanges where fence connectors should be located when the post guide rests on a fence post. The fence jig also provides reference edges and power saw cutting guides for accurately cutting fence panels. | 4 |
RELATED APPLICATION
This is a continuation of application Ser. No. 11/953,807 filed Dec. 10, 2007, which is a continuation of application Ser. No. 10/304,833 filed Nov. 26, 2002, both of which are hereby incorporated in their entirety by reference herein.
BACKGROUND OF THE INVENTION
The present invention is broadly concerned with a control valve for a medical fluid infusion device. More particularly, it is concerned with a positive pressure actuated flow control valve that permits flow of a liquid from a reservoir, through a cannula and into a patient, while resisting reflux.
Medical infusion therapy employs peripheral and central intravascular devices such as venous and arterial catheters as well as peripherally inserted central venous catheters to deliver fluids, blood products, and pharmaceuticals, including antibiotics and biologics as well as parenteral nutrition. Intravascular devices may also be coupled with pressure monitoring systems.
Regardless of the location of the insertion site of the catheter or the placement of its terminus, intravascular devices, and central venous catheters (CVCs) in particular, are subject to retrograde blood flow into the catheter lumen whenever the pressure in the patient's vascular system exceeds resistance at the supply end of the catheter. This may occur, for example, when fluid pressure drops because a gravity supply source is empty, when an injection port is opened by removal of a syringe, or when a stopcock is opened.
Retrograde blood flow is known to contribute to complications such as catheter-related septicemia, venous thrombosis, superior vena cava syndrome, pulmonary embolism and phlebitis. Thrombus formation may cause partial or complete occlusion of the catheter. Partial occlusion results in impaired sampling and fluid administration. Complete occlusion causes the catheter to lose patency, necessitating removal and replacement, so-called “unscheduled restarts”.
Catheter reflux-induced thrombosis is not merely a mechanical complication, since it appears to be a major contributor to catheter related bloodstream infections associated with the use of long term catheters. Such infections are associated with increased morbidity and mortality as well as increased health care costs associated with extended hospitalization.
Attempts have been made to develop improved intravascular devices in order to address the mechanical and infectious complications previously described. Peripherally inserted central venous catheters (PICCs) are known to reduce the incidence of thrombosis and phlebitis as well as commonly reported central catheter-related infections. However, PICC devices are not suitable for all applications, particularly where the solution to be administered has high osmolarity or may be a pH irritant. And patients with PICC infusion still experience thrombus formation and phlebitis at statistically significant levels.
Guidewire assisted exchange has also been employed to achieve a lower rate of mechanical complications following insertion of replacement catheters. However, patients may experience bleeding, hydrothorax and subsequent catheter related infections.
In-line filters have also been employed to reduce infusion-related phlebitis. However, they have not been found to prevent intravascular device-related infections. And use of such filters is not regarded as mechanically favorable, since solution filtration may be accomplished more efficiently prior to infusion and the filters themselves are subject to blockage.
Impregnated catheters and needle-free devices have also been employed. Although they have not yet been thoroughly evaluated, antimicrobial coated or impregnated catheters appear to be more effective for central venous use than for peripheral use. There are concerns, however, that they may foster development of resistant bloodstream pathogens. Needle-free infusion systems also have not yet been fully studied, although one investigation has shown survival of skin flora in needleless infusion systems.
There have also been attempts to develop methods of using conventional intravascular devices in order to prevent catheter-related thrombus formation and to maintain catheter patency. Turbulent positive pressure flushing with anticoagulant heparin solution, use of thrombolytic agents such as urokinase, streptokinase and t-Pa, and prophylactic warfarin administration have all been employed.
However, some in vitro studies have suggested that heparin flush solutions may serve to enhance growth of Coagulase-negative staphylococci (CoNS). The United States Public Health Service, Centers for Disease Control and Prevention (CDC) has cited CoNS as “the primary pathogen causing catheter-related infections”. It has recommended clinical trials to evaluate the practice of flushing with anticoagulant solutions to prevent catheter-related infections. The CDC has also cited an association between use of low dose heparin and thrombocytopenia and thromboembolic and hemorrhagic complications.
All of the preventive methods that are currently available appear to contribute in some manner to general health care delivery problems, such as delay, increased requirements for nursing care, pharmaceutical and supply costs, increased patient risk and discomfort.
Accordingly, there is a need for an improved intravascular device that will resist retrograde blood flow and thereby reduce rates of thrombus formation, catheter-related blood stream infection, and unscheduled restarts and thereby extend catheter indwelling times.
SUMMARY OF THE INVENTION
The present invention is directed to a pressure actuated flow control valve for an infusion catheter which permits gravity flow of a liquid through the catheter and into a patient while resisting back flow of blood from the patient and into the catheter. The valve includes a hemispherical dome-shaped body having concave inner and convex outer surfaces. A normally closed, slit communicates between the surfaces. The slit is configured so that it is longer on the convex outer surface than on the concave inner surface. The cross-sectional thickness of the dome diminishes in the area adjacent the slit, reducing total apical deflection upon collapse of the slit toward the concave surface. The dome inner surface includes an orthogonal rib that biases the wall of the dome adjacent the slit to a closed position. Upon application of a predetermined pressure, the slit opens toward the convex surface for facilitating fluid flow in the intended direction. At lower pressures, the slit resumes a closed position to check fluid flow. Relatively greater reverse pressure is required to collapse the slit toward the concave surface to permit reverse fluid flow. The valve includes an outstanding circumferential flange for engagement within a housing.
Objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a combination diagrammatic and perspective, partially exploded view of a flow control valve assembly in accordance with the invention, installed in a medical fluid infusion system.
FIG. 2 is an enlarged sectional view taken along line 2 - 2 of FIG. 1 and shows details of the housing construction.
FIG. 3 is a front perspective view of the valve depicted in FIG. 1 .
FIG. 4 is an enlarged bottom plan view of the valve depicted in FIG. 1 .
FIG. 5 is an enlarged top plan view of the valve depicted in FIG. 1 , showing the rib in phantom.
FIG. 6 is a further enlarged sectional view taken along line 6 - 6 of FIG. 4 and shows details of the valve slit.
FIG. 7 is a still further enlarged sectional view taken along line 7 - 7 of FIG. 4 and shows details of the rib.
FIG. 8 is a fragmentary sectional view similar to the view shown in FIG. 2 at a reduced scale, showing the valve in an open, forward fluid flow enabling position.
FIG. 9 is similar to the view depicted in FIG. 8 , showing the valve in a collapsed, reverse fluid flow enabling position.
FIG. 10 is an enlarged sectional view of a valve assembly incorporating an alternate threaded Luer housing.
FIG. 11 is an enlarged bottom plan view of an alternate valve having a cylindrical rib configuration.
FIG. 12 is an enlarged sectional view taken along line 12 - 12 of FIG. 11 and shows details of the valve slit.
FIG. 13 is an enlarged bottom plan view of a second alternate valve having a cruciform rib configuration.
FIG. 14 is an enlarged sectional view taken along line 14 - 14 of FIG. 13 and showing details of the rib.
The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure.
Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, the words “distally” and “proximally” will refer to directions respectively toward and away from a patient.
Referring now to the drawings, a pressure actuated flow control valve assembly in accordance with the invention is generally indicated by the reference numeral 10 and is depicted in FIGS. 1 and 2 . FIG. 1 illustrates exemplary use of the valve assembly 10 installed in-line between an intravascular device 12 such as an intravenous (IV) fluid delivery catheter set and an intravascular fluid source 14 , such as an IV fluid reservoir. Those skilled in the art will appreciate that the pressure actuated valve assembly 10 can also be used in conjunction with a variety of other medical fluid delivery devices, such as an arterial catheter and associated chemotherapy fluid reservoir and/or pressure monitoring device, or a gastrostomy tube set having a corresponding fluid reservoir.
The intravascular device 12 includes an elongate, flexible catheter 16 having an outer surface and an inner surface defining a lumen or fluid passageway 18 . A distal end of the catheter 16 is adapted for insertion into a vein of a patient. The outer surface of the proximal end of the catheter 16 is overmolded by a compression strain relief cuff 20 and is coupled with a Y-connector 22 , which serves as a manifold for coupling a pair of connector tubes 24 in fluidic communication with the single catheter 16 . Each connector tube 24 has an outer surface and an inner surface defining a lumen 26 , and proximal and distal end portions 28 and 30 respectively. The proximal end portions 28 are each overmolded by a compression strain relief cuff 32 . The Y-connector 22 receives the distal end portions 30 . While FIG. 1 depicts an intravascular device 12 having two connector tubes 24 , it is foreseen that any operable number of such tubes may be employed, including a single tube. In addition, while FIG. 1 depicts only the distal end of the catheter 16 as indwelling, the entire intravascular device 12 may be constructed for indwelling installation and use.
As more fully described herein, each connector tube proximal end portion 28 is coupled with a valve assembly 10 , which in turn is coupled with a connector 34 . The connector 34 has a generally cylindrical overall shape and is hollow and open at one end to receive the valve assembly 10 . The connector 34 includes a threaded interior surface 36 and an exterior surface 38 that is swaged or flanged to facilitate gripping. One end of the connector 34 is axially apertured to permit coupling with a supply tube 40 having an outer surface and an inner surface defining a fluid passageway or lumen 42 . The outer surface of the supply tube 40 adjacent the connector 34 is equipped with a molded fitment 44 to accommodate tubing attachment. The proximal end of the supply tube 40 is coupled with the fluid reservoir 14 so that the lumen 42 is in fluidic communication with the reservoir 14 .
Although not shown in FIG. 1 , the connector 34 may also be equipped with a stopcock or a plurality of infusion ports with plugs for receiving a syringe and/or needle. A pump may be installed in line with the supply tube 40 , which may also be equipped with clamps (neither is shown).
The catheter 16 , connector tubes 24 and supply tube 40 are flexible and pliant to facilitate placement, usage, and to minimize both mechanical insult to the blood vessels and patient discomfort during long-term use. They may be constructed of any suitable medical grade material, such as, for example, polyethylene, polyvinyl chloride, Teflon, silicone elastomer or polyurethane or mixtures thereof. The material may be coated or impregnated with an antimicrobial or antiseptic composition to reduce bacterial adherence and biofilm formation. The catheter 16 may also be constructed of a radiopaque material in order to facilitate imaging for locating any breaks and/or separated sections.
The strain relief cuffs 20 and 32 and fitment 44 are constructed of an elastomeric medical grade synthetic resin material. The connector 34 may be constructed of a medical grade rigid or semirigid synthetic resinous material suitable for supporting an operable threaded connection, such as, for example, polyvinyl chloride or polycarbonate.
As best shown in FIGS. 1 and 2 , the valve assembly 10 broadly includes a housing 46 supporting a valve member 48 . The housing 46 has an elongate, stepped external configuration surrounding an internal fluid passageway or lumen 50 . The lumen 50 has an enlarged diameter adjacent the proximal end to form a hemispherical cavity 52 sized for receiving the dome-shaped valve 48 . The housing 46 includes a hub portion 54 , which is shown positioned for installation in a proximal orientation and a body portion 56 shown in a distal orientation. The housing 46 is formed of a suitable medical grade synthetic resin, such as for example, a polycarbonate.
The body 56 includes a tapered nipple 58 sized for reception within the lumen 26 of a connector tube 24 . The nipple 58 includes a plurality of spaced, radially expanded annular barbs 60 . While FIG. 1 depicts two barbs 60 evenly spaced along the nipple 58 , it is foreseen that any number of barbs 60 may be included with any suitable degree of radial expansion and in any spaced configuration.
The proximal end of the nipple 58 is radially expanded to form a midportion or barrel 62 , having a pair of opposed axial flanges or finger tabs 64 to facilitate manual rotation of the valve assembly 10 . The barrel 62 is radially expanded at the proximal end to form an annular seat 66 for receiving the hub 54 . The seat 66 includes a series of concentric steps 68 perpendicular to the axis of the lumen 50 , each step 68 presenting a concentric side wall 70 , which is coaxial with the lumen 50 . The proximal step 68 serves as a valve seat 72 . The surface of the valve seat 72 includes a raised annular ring or stake 74 , having an angular or pointed, proximal surface adapted for gripping engagement of a valve 48 .
The hub 54 has a hollow, stepped cylindrical configuration, including a distal skirt portion 76 and a proximal neck 78 with a central lumen 80 . The inner surface of the skirt includes a series of concentric steps 82 , each including a concentric side wall 84 for mating engagement with respective corresponding steps 68 and side walls 72 of the body portion 56 . The proximal step serves as a valve seat 86 . The surface of the valve seat 86 includes a raised annular ring 88 , for gripping engagement of a valve 48 . One of the steps 82 subtends an angle of less than 90 to form an energy director 90 . The neck 78 includes a series of female Luer lock threads, 92 designed for mating engagement with corresponding standard male IV Luer threads in the connector 34 . Alternately, a conventional threaded or bayonet-type fitting may be substituted in the neck 78 and connector 34 for the Luer fittings shown and described.
As best shown in FIGS. 3-9 , the valve member 48 includes a dome portion 94 coupled with an outstanding radial flange or lip portion 96 . It is also foreseen that the flange 96 may be of lesser radial extent or omitted entirely. The valve 48 has outer and inner surfaces 98 and 100 respectively and includes a circumferential slit 102 centered on the dome 94 . The slit 102 extends across the fluid flow path for providing fluid communication through the valve 48 when it is in an open position. As best shown in FIGS. 3 and 5 , the slit 102 is bisected by a central axis C, is coplanar with a slit axis S, and is crossed by a rib axis R perpendicular to axis S. As shown in FIG. 6 , the slit 102 has outer and inner margins 104 and 106 and a pair of ends 108 and 110 . Because the outer margin 104 is longer than the inner margin 106 , the ends 108 and 110 subtend an angle.
As illustrated in FIGS. 6 and 7 , the outer surface 98 of the valve dome 94 has the symmetrical configuration of a hemisphere. It is also foreseen that the dome 94 may be configured as a spherical cap or chordal segment (the region of a sphere that lies above a chordal plane that does not pass through the center of the sphere) which may be either greater or less than one-half of a sphere. The valve dome 94 need not be strictly hemispherical or partially spherical; however it is preferred that it be at least dome-like or cap-like. The outer and inner surfaces 98 and 100 of the valve dome 94 are not perfectly concentric. The inner surface 100 of the valve dome 94 is depicted as having a generally hemispherical configuration, with a slightly increased curvature as it approaches the axis C. As a result, the dome 94 has a variable wall thickness, which diminishes as it approaches an apex region of the dome 94 at the axis C.
The inner surface 100 of the valve dome 94 is shown in FIGS. 4 and 6 - 7 and in FIG. 5 in phantom to include an elongate rib 112 . The rib 112 extends generally circumferentially inwardly in the direction of axis R, perpendicular to and centered on the slit 102 , and serves to bias the slit 102 to the closed position depicted in FIG. 3 . The rib 112 is of approximately rectangular overall configuration, including a pair of spaced, parallel side surfaces or sides 114 and a pair of ends 116 convergent with the inner surface 100 of the valve dome 94 .
As shown in FIGS. 6 and 7 , the rib 112 has a depth 118 which diminishes as the ends 116 are approached. The rib 112 may be constructed so that the depth 118 also diminishes as the sides 114 are approached. The rib 112 is bisected by the slit 102 at a center portion 120 of the rib. Thus, the wall thickness of the dome thins as it approaches the geometric center of the slit 102 , and is reinforced at the center along axis R by the depth of the rib 112 . It is foreseen that, rather than bisecting the rib 112 , the slit 102 may intersect the rib 112 eccentrically or asymmetrically, or that the slit 102 may be coextensive with the rib 112 . It is also foreseen that the ends of the rib 116 could be truncated (not shown) so that the depth 118 does not diminish as the ends 116 are approached, or that the ends 116 could be constructed so that the depth 118 increases as the ends are approached.
FIGS. 11 and 12 depict a valve 122 having an alternate rib construction. The structure of the valve 122 is substantially identical to that previously described, and the numbering and description of like elements and axes is hereby adopted and will not be reiterated. The valve 122 includes a circumferential slit 124 centered on the dome 94 . The inner surface 100 of the dome 94 includes a rib 126 having an approximately hemi-cylindrical overall configuration, including a curvate surface 128 and a pair of ends 130 convergent with the inner surface 100 of the valve dome 94 . As previously described, the rib depth diminishes as the ends 130 are approached.
FIGS. 13 and 14 depict a valve 132 having a second alternate rib construction. The structure of the valve 132 is also substantially identical to that previously described, and the numbering and description of like elements and axes is also adopted and will not be reiterated. The valve 132 includes a circumferential slit 134 , also centered on the dome 94 . The inner surface 100 of the valve dome 94 includes a rib 136 having an approximately X-shaped or cruciform overall configuration. The rib 136 has a first leg 138 and a second leg 140 , each of approximately rectangular overall configuration. Each of the legs 138 and 140 include a pair of sides 142 and 144 , and a pair of ends 146 and 148 respectively. The first leg 138 is coextensive with the slit 134 , whereas the second leg 140 is orthogonal to the slit 134 . The leg ends 146 and 148 are convergent with the inner surface 100 of the valve dome 94 . As previously described, the rib depth diminishes as the ends 146 and 148 are approached. Those skilled in the art will appreciate that, in addition to the rib configurations previously described, the rib may be of oblong, elliptical, quadrilateral, star-shaped, curvate, compound curvate, circular, curvilinear or any other suitable configuration.
The valve dome 94 , lip 96 and ribs 112 , 126 and 136 are of unitary construction and are formed of a resilient medical grade elastomeric material such as a silicone elastomer. The characteristics of the material used to construct the valve 48 and housing 46 , the dimensions of the valve dome 94 , flange 96 , ribs 112 , 126 and 136 and slit 102 , 124 or 134 the wall thickness of the valve 48 as well as the magnitude of thinning of the wall as it approaches the top of the dome 94 and location of the slit 102 , 124 or 134 (whether centered on the dome or eccentric) are variables which collectively determine both the magnitude and difference between individual pressure differentials P.sub.1 and P.sub.2 under which the slit 102 , 124 or 134 flexes in forward and reverse fluid-enabling manner.
The valve assembly 10 may be constructed by aligning the valve member 48 or 122 or 132 on the body portion 56 of the housing 46 so that the outer surface 98 of the valve flange 96 engages the body valve seat 72 and projecting stake 74 , and is received within cavity 52 .
The hub 54 is installed over the body 56 with the body and hub steps 68 and 82 in mating engagement and the hub valve seat 86 and projecting ring 88 overlying the valve flange 96 . The hub 54 and body 56 are then subject to ultrasonic welding under pressure to form a hermetic seal. The energy director 90 serves to direct the ultrasonic melt, so that the surfaces of the mated steps 68 and 82 fuse and the valve flange 96 is captured between the stake 74 and the ring 88 in a generally S-shaped cross sectional configuration as depicted in FIG. 2 . In this manner, the valve 48 or 122 or 132 is secured in place against dislodgement by fluid pressure or force exerted by any object which might be inserted into the housing lumen 50 . Alternatively, the hub 54 and body 56 may be secured together by an adhesive composition, by a strictly mechanical junction, or by other arrangements.
The valve assembly may be installed in an intravascular device 12 by grasping the housing 47 and using the finger tabs 64 to rotatingly introduce the nipple 58 into the lumen 26 at the proximal end portion 28 of a connector tube 24 until all of the barbs 60 are received within the lumen 26 . The barbs 60 serve to frictionally engage the inner surface of the connector tube lumen 26 in a force fit. It is foreseen that, where a single IV line is to be employed, a connector tube 24 may be unnecessary so that the housing 46 may be introduced directly into the catheter lumen 18 at the proximal end of a catheter 16 . A connector 34 is aligned over the neck 78 and rotated until the threaded interior surface 36 tightly engages the threads 92 of the neck 78 . More than one valve assembly 10 may be installed in-line in an intravascular device 12 .
In use, the catheter 16 is inserted into a blood vessel of a patient, so that the catheter lumen 18 is in fluidic communication with the patient's blood. If the catheter 16 is to be centrally placed, it is then threaded into a large central vein where it may remain indwelling for a prolonged period of time.
An intravascular fluid source or reservoir 14 is coupled with the supply tube 40 so that the supply tube lumen 42 is in fluidic communication with the reservoir. Gravity fluid flow is initiated from the fluid source 14 by any conventional means, such as by opening a stopcock or removing a clamp. Fluid flow may also be initiated by actuating a pump. Fluid from the reservoir 14 travels in a flow path through the supply tube 40 into the housing lumen 50 and through the valve 48 or 122 or 132 until it contacts the inner surface 100 of the dome.
As shown in FIG. 8 , when the forward fluid flow exerts or exceeds a predetermined fluid pressure differential P.sub.1 or cracking pressure against the dome inner surface 100 , the slit 102 flexes distally to an open, forward flow-enabling position. In valves 122 and 132 , similar pressure conditions cause similar flexion of the respective slits 124 and 134 . The axial thinning of the dome 94 , the shorter length of the slit inner margin 106 with respect to the slit outer margin 104 , and the angle subtended by the ends of the slit 108 and 110 all cooperate to facilitate flexing of the slit 102 or 124 or 134 at a relatively low pressure differential, such as is provided by the force of gravity on an elevated fluid reservoir.
The slit 102 or 124 or 134 remains in an open position to permit the flow of fluid in a forward direction as long as the pressure differential P.sub.1 is maintained against the dome inner surface 100 . When the fluid supply in the fluid reservoir 14 is exhausted, the pressure differential against the dome inner surface 100 falls below the cracking pressure P.sub.1, and the rib 112 , or 122 or 128 serves to bias the slit 102 or 124 or 134 back into a closed, flow-blocking position, depicted in FIG. 7 . The rib 112 , or 122 or 128 also biases the closed slit margins 104 and 106 into sealing alignment, so that there is no overlap which might permit leakage through the valve. The pressure differential P.sub.1 is preselected by design so that the slit 102 or 124 or 134 closes while a fluid head remains in the supply tube 40 , so that air does not enter the valve 48 or 122 or 132 .
At times, it may be necessary to permit reverse fluid flow, for example to withdraw a blood sample. In such instances, a syringe may be inserted into the hub 54 and the plunger withdrawn to create a negative pressure. As shown in FIG. 9 , when a predetermined fluid pressure differential P.sub.2, or collapsing pressure, is exerted or exceeded against the dome outer surface 98 , the slit 102 or 124 or 134 flexes proximally to an open, reverse flow-enabling position. Flexing of the slit is accompanied by proximal collapse of a portion of the dome 94 . Because of the axial thinning of the dome 94 in the region of the slit once the pressure differential P.sub.2 is reached, only a limited portion of the dome flexes proximally, and the entire dome 94 does not invert into the hub lumen 80 . In this manner, the volume of fluid displace back in to the housing lumen 50 is minimized when the pressure falls below P.sub.2 and the rib 112 or 122 or 128 biases the slit 102 or 124 or 134 back into a closed, fluid flow blocking position depicted in FIG. 7 . Advantageously, the combination of the hemispherical shape of the dome 94 , the angular ends of the slit 102 , the anterior thinning of the dome 94 in the region of the slit 102 or 124 or 134 , and the rib 112 or 122 or 128 combine to provide a valve 48 having a relatively low cracking pressure P.sub.1, a relatively high reflux pressure P.sub.2 and minimal fluid displacement following reverse fluid flow. This combination of features permits forward fluid flow by gravity from a reservoir and into a patient, while inhibiting thrombus promoting fluid backflow and minimizing reflux volume.
The structure of a an alternate valve assembly housing is illustrated in FIG. 10 and is generally indicated by the reference numeral 150 . The housing 150 has an elongate, generally cylindrical external configuration surrounding a fluid passageway or lumen 152 , which widens proximally for receiving the dome-shaped valve member 48 previously described. The housing 150 includes a hub portion 154 and a body portion 156 .
The distal portion of the body 156 is configured as a standard Luer connector, including a standard Luer taper 158 and standard male luer lock threaded overmantle 160 or internally threaded collar. The proximal portion of the body 156 and distal portion of the hub 154 are matingly stepped as previously described with respect to the body 56 and hub 54 . The proximal portion of the hub 154 is configured with a truncated, Luer threaded top 162 .
In use, the male Luer body 156 may be rotatingly coupled with any standard female Luer connection, while the female Luer hub 154 may be coupled with any standard male Luer connection in order to install the valve assembly housing 150 in-line between an intravascular fluid source and an indwelling catheter 16 . The operation of the valve member 48 within the housing 150 is substantially the same as previously described with respect to the valve member 48 within the housing 46 .
It is to be understood that while certain forms of the present invention have been illustrated and described herein, it is not to be limited to the specific forms or arrangement of parts described and shown. | A pressure actuated flow control valve for an infusion catheter permits gravity flow of a liquid through the catheter and into a patient while resisting back flow of blood from the patient and into the catheter. The valve has a hemispherical body with an outstanding circumferential flange and a normally closed, diametric slit. The slit is longer on the convex outer surface than on the concave inner surface. Dome thickness diminishes in the area adjacent the slit, reducing total apical deflection upon collapse of the slit toward the concave surface. An inner orthogonal rib biases the slit closed. Upon application of a predetermined pressure, the slit opens toward the concave surface to permit forward fluid flow. At lower pressures, the slit closes to check fluid flow. Greater reverse pressure is required to collapse the slit toward the concave surface to permit reverse fluid flow. | 0 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.